US3885438A - Automatic fluid injector - Google Patents

Abstract

Apparatus for automatically accurately measuring and injecting quantities of fluid specimens, or samples, into various media, e.g., a receptacle or inlet of a modern analytical instrument. The automatic fluid injector includes generally (a) an injector, or syringe assembly, inclusive of a needle syringe per se, (b) an injector feed assembly for automatically continuously purging, cleaning and filling the said syringe, and (c) a magazine, or feed tray, for transporting fluid specimen containing vials to the injector feed assembly for pick-up of the fluid specimen, and delivery to the syringe of the syringe assembly. Means are provided for movement of the syringe along a straight path for insertion and withdrawal of the needle from the inlet of the analytical instrument. A reciprocable hollow probe, or pair of probes, associated with the injector feed assembly picks up a fluid specimen from a fluid containing vial delivered by the magazine or feed tray, and conveys the fluid to the syringe of the syringe assembly. A predetermined portion of the fluid specimen is trapped and accurately measured within the syringe, and the syringe is carried forward to insert the needle portion thereof through the inlet of the analytical instrument, the sample is then injected, and the needle then withdrawn. The several assemblies are properly housed, and automatic controls provide for cyclically cleaning, purging, filling and injecting fluid specimens.

Description

United States Patent 1 Harris, Sr. et al.

[ l AUTOMATIC FLUID INJECTOR [76] Inventors: Rano J. Harris, Sr., 1945 Carolyn Sue Dr.; Rana J. Harris, Jr., 9880 S. Riveroaks Dr., both of Baton Rouge, La. 708l5 Notice: The portion of the term of this patent subsequent to Aug. 28, 1990, has been disclaimed.

[22] Filed: May 31,1973

21 Appl. No.: 365,552

Related US. Application Data [63] Continuationinpart of Ser. No. 223,663, Feb. 4,

1972, Pat. No. 3,754,443.

[52] U.S. Cl. 73/422 GC; 73/423 A [SH Int. Cl. H GOln 1/14 [58] Field of Search 73/423 A, 422 GC; 23/259 [56] References Cited UNITED STATES PATENTS 3,479,880 ll/l969 Mutter et al. 73/423 A 3,754,443 8/[973 Harris, Sr. et al. 73/423 A Primary ExaminerS. Clement Swisher Attorney, Agent, or Firm-Llewellyn A. Proctor [57] ABSTRACT Apparatus for automatically accurately measuring and 1*May 27, 1975 injecting quantities of fluid specimens, or samples, into various media, e.g., a receptacle or inlet of a modern analytical instrument. The automatic fluid injector includes generally (a) an injector. or syringe assembly, inclusive of a needle syringe per se, (b) an injector feed assembly for automatically continuously purging, cleaning and fil!ing the said syringe, and (c) a magazine, or feed tray, for transporting fluid specimen containing vials to the injector feed assembly for pickup of the fluid specimen, and delivery to the syringe of the syringe assembly. Means are provided for movement of the syringe along a straight path for insertion and withdrawal of the needle from the inlet of the analytical instrument, A reciprocable hollow probe, or pair of probes, associated with the injector feed assembly picks up a fluid specimen from a fluid-containing vial delivered by the magazine or feed tray, and conveys the fluid to the syringe of the syringe assembly. A predetermined portion of the fluid specimen is trapped and accurately measured within the syringe, and the syringe is carried forward to insert the needle portion thereof through the inlet of the analytical instrument, the sample is then injected, and the needle then withdrawn. The several assemblies are properly housed, and automatic controls provide for cyclically cleaning, purging, filling and injecting fluid specimens.

22 Claims, 19 Drawing Figures PATENTEDHAY 2 7 1975 "ATEMEBWQY 1975 SHEET AUTOMATIC FLUID INJECTOR REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of related US. Pat. No. 3,754,443, the disclosure of which is herewith fully incorporated by reference. The present invention relates generally to an automatic fluid injector, or apparatus, for automatically measuring and injecting accurately measured quantities of fluids. More particularly, it relates to apparatus, especially fluid injection devices or syringes, for continuous automatic measurement and injection of very small, accurately measured quantities of liquid specimens into various media, e.g., modern analytical instruments.

Fluid injection devices, particularly needle syringes, have gained wide acceptance by the industry, and by the scientific community, generally, for use in dispensing infinitesimally small, accurately measured fluid specimens, e.g., to modern analytical instruments such as mass spectrometers and gas chromatographs. Such syringes embody apparatus comprising a tubular body or barrel, on the forward end of which is fitted a hollow or tubular needle and, at the opposite end, a slidable plunger which travels within the barrel. Syringes of such character, and related devices, are capable of dispensing very small fluid specimens, accurately mea sured, on the order of a few microliters, or very small fractions of a microliter, e.g., from about 0.01 to about microliters, or fractional parts thereof.

In recent years, due to the obvious advantages offered by the combination of automatic fluid injection instruments, and modern data gathering techniques, which greatly reduce operating manpower without decrease in accuracy, there is considerable demand for improved automated devices of these types.

It is, accordingly, a primary object of the present invention to provide new and novel fluid injectors readily adaptable to automatically perform the basic cyclic functions of filling, purging and cleaning, and injecting.

A particular object is to provide apparatus capable of continuously cyclically serially withdrawing precisely measured infinitesimally small quantities of gas or liquid specimens from prefllled vials or containers, injecting the specimens in seriatim in reproducible quantities, and cleaning prior to subsequent withdrawal and injection of a subsequent specimen.

A further object is to provide apparatus of simple and relatively inexpensive construction, particularly apparatus which can be readily serviced and operated, which apparatus readily lends itself to rapid mass production techniques.

These objects and others are achieved in accordance with the present invention which embodies improvements in automatic fluid injector systems. A preferred type of automatic fluid injector is comprised generally of (a) an injector, or syrings assembly, inclusive of a needle syringe per se, (b) an injector feed assembly, or unit, for automatically purging, cleaning and filling the said syringe, and (c) a magazine, or feed tray, for transporting fluid specimen containing vials and positioning same in relation to the injector feed assembly for pickup of the fluid specimen, and delivery to the syringe of the syringe assembly. The automatic fluid injector also includes automation or control means for repetitively and automatically carrying out the functions of cleaning, purging and filling the syringe with predetermined quantities of fluid specimens, in timed sequence, and the several subassemblies of the automatic fluid injector are generally contained within a housing, or housings. The sub-assemblies constituting (a) the injector, or syringe assembly, inclusive of syringe, and (b) the injector feed assembly are preferably contained within a single housing below which is mounted (c) the maga zine, or feed tray.

The characteristics of preferred automatic fluid injectors, and the principle of their operation, will be more fully understood by reference to the following detailed description of preferred embodiments, and to the attached drawings to which reference is made in the detailed description. Similar numbers are used to represent similar parts or components in different figures, and letter subscripts are used, with a given whole numher, to designate a plurality of generally analogous parts or components. Where a capital letter is used alone with reference to a component, its use is intended to point out a sub-assembly of the combination.

In the drawings:

FIGS. 1 through 8 describe a series of views depicting a preferred automatic fluid injector, and its operation in the sequence of sampling, trapping, measuring and injecting an accurately measured volume of fluid into a medium, e.g., an inlet to an analytical instrument.

FIG. 1 is a section view of a preferred automatic fluid injector, including an automated syringe, mounted on a plate, or housing, useful for positioning said syringe, in relation to an inlet, or medium, wherein an accurately measured fluid specimen is to be injected, the automatic fluid injector including, in combination, (a) an injector, syringe or syringe assembly, (b) in injector feed assembly (or assembly for supplying a fluid specimen to the syringe of the syringe assembly, and (c) a magazine or feed tray;

FIGS. 2 and 3 are sections of the injector feed assembly, with a fragmentary view of the magazine or feed tray, depicting their operation and function;

FIG. 4 is a section of the overall combination depicted by reference to FIG. 1, showing a continued progression of the operation and function of the automatic fluid injector; and

FIGS. 5-8 are views or necessary fragmentary views showing continuation of the progression of operation of the automatic fluid injector, previously referred to, through a completion of a cycle of operation;

FIGS. 9 through 11 are section views depicting a preferred type of syringe, and its operation, as a part of the combination depicted by reference to preceding FIGS. 1 through 8;

FIGS. 12 and 13 are sectional views of other preferred modes of injector feed assemblies, as a part of the overall combination depicted by reference to FIGS. 1 through 8, or FIGS. 1 through 8 as modified by the embodiments of FIGS. 9 through 11;

FIGS. 14 and 15 depict sectional views of another preferred type of injector feed assembly, and its principle of operation, useful in any of the combination previously described; and

FIGS. I6 through 19 depict another preferred type of syringe, and its operation, for use in any of the combinations previously described.

Referring to FIG. I, and to FIGS. I through 8 generally, there is shown the principle components of an automatic fluid injector, according to one form of the invention, this including the combination of (a) an injector, or syringe assembly A, (b) an injector feed assembly B, and (c) a magazine, or feed tray, C for carrying or transporting individual fluid containing vials. These several units of the automatic fluid injector are gener ally contained within a housing and are responsive to automatic control means such as described, e.g., by reference to application Ser. No. 223, 663, supra. In brief compass, the overall nomenclature and function of these several units are as follows: (a) The injector, or syringe assembly A, is comprised generally of a needle syringe 10, which includes the usual barrel 11, Cannula or needle 12 mounted on the front end thereof, and plunger 13 mounted within said barrel 11. The plunger 13 is itself actuated by a double-acting cylinder piston unit 20, which forms a part of the overall needle syringe 10, and syringe 10 is mounted and carried on the for' ward end of a piston 31 of a double-acting cylinder pis ton unit 30 and reciprocable therewith for movement of the syringe 10 along a straight path in alignment with. e.g., a septum inlet 90; (b) the injector feed assembly B, the function of which is to provide a fluid specimen to the syringe 10, is comprised generally of a double-acting cylinder piston unit 50, the piston 51 thereof being a reciprocable hollow probe associated with means which enable said probe to act as a conduit for receipt and transfer of a fluid specimen supplied thereto under a slight pressure, which acts as a driving force, to fill the syringe l; and (c) a magazine, or feed tray, for transporting fluid specimens to a location for pick-up by the probe 51 for delivery to the syringe 10. These several subassemblies, and their function, are described more explicitly in the following paragraphs.

The syringe is constituted generally of a pair of contiguous tubular members comprising a relatively large diameter rearward section and a smaller diameter forward section 11, for convenience in manufacture. The rearward section of the syringe is constituted as a double acting cyliner-piston unit 20 with an air inlet 21 leading into the forward end of the chamber and an air inlet 22 leading into the rearward end of the chamber. The air inlets 21, 22 are provided with flexi' ble hose connections. The forward end of the chamber is provided with a tubular shaped seal or packing 23 through which the forward portion of the shaft of the piston 13 is extended, this hermetically sealing and isolating the smaller diameter forward section 11 from the rearward section 20. The forward end of the piston 13, which always remains and travels within the forward section 11 of syringe 10, is covered or capped with a resilient material, preferably Teflon, constituting a sealing head 14. A preferred method of forming seals on the forward end of movable plungers of this type is described by reference to US. Pat. No. 3,577,850 herewith incorporated by reference. A plunger stop assembly 25, of adjustable character, is located at the rearward end of the chamber and within the path of travel of the piston 13 of cylinder piston unit 20. The function of plunger stop assembly 25 is to permit piston 13 to traverse a predetermined, or pre-set, length of the chamber of doubleacting cylinder piston unit 20.

The plunger stop assembly 25 is constituted of a tubular end plug 26 provided with a forward externally threaded shank portion 27 which mates and is threadably engaged with internal threads located within the end wall forming the chamber of the double-acting cylinder piston unit 20. A relatively small diameter, internally threaded tubular section 28 is projected through the axial opening of the plug 26, is hermetically sealed therein via an O-ring 29. The tubular section 28 is ro tatably mounted within the said axial opening, though it is not movable in an axial direction. A threaded shaft 19, preferably provided with a perforated cylindrical shaped head 24, is movable along the axis of the chambet on rotation of the knob or plug 26 such that the distance which the plunger 13 is free to traverse can be adjusted or preselected. It will thus be observed that the distance between the rearward face of tubular packing 23 and the forward face of head 24, as well as the thickness of piston head 18 of piston 13, determine the distance of travel of plunger 13 within the chamber of the smaller diameter forward section 11 of the ringe 10, and that such distance can be readily set by rotation of tubular member 28 which lengthens or shortens the distance between the forward face of head 24 and the rearward face of seal 23, by movement of head 24 as the threaded shaft 19 is moved into or out of tubular section 28 due to the threaded engagement between these members. lt will be observed that the plunger 13 is reciprocated within the limits set by injection of air via line 22 into the rearward side of the cylin' der piston unit 20 to drive the piston 13 forward, and by injection of air via line 21 into the forward side of the cylinder piston unit 20 to move piston 13 rearwardly.

The smaller diameter tubular forward section 11 of the syringe 10 is generally constructed of transparent plastic or glass, and optionally scribed with indicia representative of the interval volume. The volume of the chamber formed within the tubular barrel 11 is exaggerated in the drawings for clarity and. of course, can be varied in size depending upon the volume of specimen to be accurately measured and delivered, e.g,, as where the specimen is a liquid or gas. One method of varying the volume of the chamber within barrel 11 is by adjustment of the length of stroke of the plunger, as suggested via adjustment of the plunger stop assembly 25. A cannula or needle 12 is fixed within the forward wall or upon the forward end of the barrel 11 by various means well known to the art. The needle 12 can thus be snugly fitted into the forward end of the barrel or smaller diameter tubular forward section 11 through an opening made in the forward wall. and an air-tight seal provided about the annulus between the outer wall of the needle 12 and well of the barrel 11 by means of a tubular packing or seal 17. The needle 12, provided with a forward opening 16, is extendable through horizontal opening 53 of the housing 60, and is communi cable, in proper position, with the vertical opening 54 via their intersection (or communicating channel).

The syringe 10 is, in its entirety, affixed via a mounting bracket 32 on the forward end of piston 31 of the double-acting cylinder-piston unit 30, which can be secured via mounting brackets (not shown) upon the wall of a' housing (not shown). The double-acting cylinder piston unit 30 thus includes the usual hollow air-tight casing (or enclosing wall) 36, with enclosing end walls 37, 38, and air inlet- outlet openings 33, 35. The syringe 10 is reciprocably movable along a fixed horizontal path via reciprocation of plunger 31. Forward movement of the piston 31 is accomplished by injection of fluid (e.g., air) into the rearward end of the cylinderpiston unit 30 via inlet 33, the fluid impinging upon piston head 34 of piston 31 causing the entire syringe 10 to be thrust forward, this causing passage of the needle 12 through the opening 53 of housing 60, this producing insertion of the dispensing end of the needle 12 through a septum or other type of inlet as for sample injection in a modern analytical instrument. Rearward movement of the piston 31 by injection of fluid (e.g., air) into the forward end of the unit via inlet 35 again impinges upon piston head 34 to move the syringe in the opposite direction, this causing withdrawal of the needle 12 from the sample inlet 90.

The injector feed assembly B comprises a doubleacting cylinder piston unit 50, inclusive of a piston or probe 51, the forward portion of which is mounted and reciprocable within a tubular shaped housing 60. The probe 51 is hollow or tubular, at least in part, to serve as a conduit for receipt and transfer of a fluid specimen, supplied thereto by pressurizing means described hereafter, to fill the syringe 10. In the embodiment described by reference to FIG. 1, and associated figures, the injector feed assembly B is vertically oriented, as contrasted with the horizontal orientation of the syringe assembly A. Generally, the double-acting cylinder piston unit 50 and tubular housing 60 are formed or fabricated as a unitized assembly, and mounted within a main housing (not shown) via appropriate fastening means. It will be observed, in general, that the probe 51 is reciprocable and can be moved or projected downwardly through the complete length of the axial opening 54 of tubular housing 60, through the opening 55 of a mounting plate 56 of a housing (not shown), for penetration of the septum 81 of a specimen filled vial 82. The probe 51 is provided with various openings 64, 65, 66 to enhance its utility to serve as a conduit for pick-up and transfer of fluid, and means are provided for pressurizing the fluid contents of the vial 82 so that fluid from a vial 82 can be picked up by the probe 51 and conveyed upwardly for delivery to the syringe 10.

The double-acting cylinder piston unit 50, like double-acting cylinder piston unit 30, also includes an enclosing side wall 52, an enclosing upper end wall 57, and an enclosing lower end wall formed by the upper face of tubular member 60. An O-ring 58 is provided to more effectively seal the lower end of the unit 50 and air inlet- outlet openings 61, 62 are provided for reciprocation of probe 51, via alternate impingement of air on the opposite faces of piston head 59. A safety line 63 is optionally provided to serve as an escape route for air which might escape from cylinder-piston unit 50, as in the situation of a worn or leaky seal, e.g., O-ring 58.

A chamber 70, with its inlet means 71, located within the tubular housing 60 provides a preferred means of transmitting a pressurizing inert or non-reactive fluid, e.g., air, nitrogen, or the like, to a vial 82 to effect transfer of the fluid specimen therefrom to probe 51 for pick-up and delivery of same to syrine 10. Suitably, for manufacturing convenience, the tubular member 60 is formed of two sections 60, 60B, and chamber 70 is formed by these members. Chamber 70 is thus formed by fitting together of the abutting face of member 60,, 60 each of which contains a cylindrical cut-away sec tion, and the air-tight character thereof is assured by an inner lining or bushing 7 located between the interface of tubular members 60,, 60 O-rings 72, 73 further assure the air-tight nature of the fit.

The double-acting cylinder piston unit 50, like doubleacting cylinder piston units 20, 30, are generally pneumatic, air being used as the driving medium. Virtually any source of pressurized fluid, e.g., hydraulic fluid or pneumatic pressure, however, can be used. The probe 51 of cylinder-piston unit 50 can thus be moved upwardly via pressurized fluid injected via gas inletoutlet port 62, and downwardly by injection of pressurized fluid injected via gas inlet-outlet port 61. When the piston 51 is thrust to its extreme downward position, by fluid pressure acting against piston head 59, the lower terminal end of the probe 51 is projected through the opening 55 in the wall of the lower housing, through a centrally located opening through a septum cap 81 of a vial 82 for pick-up of a fluid specimen, delivered into position by action of a feed tray or magazine 80.

In the several embodiments of this invention, a magazine or feed tray 80 is provided for conveying fluid specimen-containing vials 82 in seriatim to a location beneath the opening 55 or housing 56 for pick-up by the probe 51. The vials 82 are of open screw top type, sealed with a elastomer septum 81 to prevent leakage or contamination and to permit pressurization. As the vials 82 are moved into position beneath the opening 55, the probe 51 can be moved downwardly and projected through the opening 55 at the bottom of housing 56 to pass through the open caps and penetrate the septum of the vials 82 for pick-up of the fluid specimen.

An operating cycle is described by reference to FIGS. 2 through 8, these figures depicting a series of views describing the filling, injecting, cleaning and purging of syringe 10. The timed sequence can be repeated ad infinitum, as follows:

a. Referring first to FIG. 2, probe 51 is pushed downwardly from an upward starting position (FIG. 1) by pressurized air which enters into the chamber of the cylinder-piston unit 50 via the inlet-outlet port 61 to impinge on piston head 59. Simultaneously, air is exhausted via air inlet-outlet port 62. The probe 51 is side vented in three locations, and the side vent openings 64, 65, 66 are communicated one with the other by an axial opening through the probe. The septum 81 of the air-tight vial 82, located between the threaded cap 83 and the upper shoulder of the glass vial 84, is penetrated by the sharp, or pointed, end of probe 51. As the upper side vent opening 64 passes into the chamber 70 formed within tubular member 60 to which a gas is admitted via the pressure gas inlet 71, gas enters into side vent openings 64, 65 and flows downwardly through the axial opening through hollow probe 51 to exit via the lower side vent opening 66 and into the vial 82, pressurizing the latter.

b. Prior to the time that probe 51 has reached its most downward position, as shown by reference to FIG. 3, the chamber 70 and pressure gas inlet 71 are no longer open to the upper side vent openings 64, 65 of the probe 51. Rather, the upper side vent openings 64, 65 of the probe 51, at the maximum downward position of piston 51, open to the valved drain line 67 and horizontal opening 53, the latter communicating openings 65 with the axial opening at the dispensing end of needle 12. At this point in time, fluid from vial 82 flows through the axial opening through probe 51 and (plunger 13 of the syringe 10 being withdrawn creating a vacuum) into the needle 12. On terminating of the downward movement of probe 51, inlet-outlet port 62 is in fully vented position.

c. Reference is now made to FIG. 4 of the drawings. Air is injected via line 22 into the rearward side of cylinder-piston unit 20, the air passing through perforated head 24 to impinge on plunger head 18 of plunger 13, driving the plunger 13 forvvard. Fluid specimen is discharged from the dispensing end of needle 12, entering via side opening 65 into the axial opening of probe 51 whereon it is discharged via side opening 64 into valved drain line 67. Suitably. the opening 67 is sized and valved such that fluid is discharged therefrom rather than passing downwardly through the axial opening of the probe 51 to serve as contamination.

(1. Referring to FIG. 5, the direction of movement of plunger 13 is reversed by passage of air into inletoutlet line 21, with simultaneous venting of inlet-outlet line 22, air impinging on head 18 of plunger 13 to drive it again to the rear, its motion terminating on impingement against perforated head 24. Reciprocation of the plunger 13 at this time is generally effected to flush and clean the needle 12, the contaminated fluid being discharged through drain line 67. Generally, a plurality of reciprocations are employed to thoroughly clean the needle 12, the last quantity of liquid being held for injection. as shown by reference to the said FIG. 5.

e. Referring to FIG. 6, the probe 51 is next moved away from its position blocking horizontal opening 53, to permit passage of needle 12. Probe 51 is thus lifted clear of opening 53 by injection of air into inlet-outlet opening 62 of cylinder-piston unit 50, while simultaneously inlet-outlet opening 61 is vented, air impinging upon the under face of plunger head 59 driving probe 51 upwardly. The injector feed assembly A portion of the automatic fluid injector is now repositioned as shown by reference to FIG. 1.

f. The entire syringe 10, as shown by reference to FIG. 7, is now moved forward by air injected via inletoutlet port 33 into cylinder-piston unit 30, while inletoutlet line is in vented position, the air impinging upon the piston head 34, causing the piston 31 to be thrust forwardly and cause the needle 12 to be inserted into inlet 90 of an analytical instrument. e.g., a gas chromatograph.

g. Referring to FIG. 8, air to inlet-outlet port 22 (not shown) drives plunger 13 to its extreme forward position, the head 14 thereof transversing the length of the chamber 11 to inject the liquid specimen into the inlet 90. Simultaneously. carrier gas is admitted via line 91 to aid in the injection of the fluid specimen into the instrument.

h. The plunger 13 is next repositioned by admission of air into inlet-outlet port 21, of cylinder-piston unit 20, while inlet-outlet port 22 is vented, the plunger 13 of syringe 10 being repositioned as shown by reference to FIG. 1.

i. The syringe 10 is next repositioned by injection of air into inlet-outlet port 35, of cylinder-piston unit 30, while inlet-outlet port 33 is vented, the entire syringe 10 being repositoned as shown by reference to FIG. 1.

A second preferred form of this invention is depicted by reference to FIGS. 9 through 11, this embodiment including essentially the same overall combination of (a) a syringe assembly A, (b) an injector feed assembly B, and (c) a magazine or feed tray C, as generally described by reference to FIGS. 1 through 8. In fact, in this embodiment. essentially the same injector feed assembly B and magazine, or feed tray, C can be used, as desired.

Referring specifically to FIG. 9, the drawing thus shows the same injector feed assembly B as described by reference to FIGS. 1 through 8, the only exception being that probe 51 contains one less opening (opening 6-1 is omitted), The magazine or feed tray is. or can be. identical to that formerly described by reference to the preceding figures The cylinder-piston unit 31), upon the piston 31 of which the syringe is mounted, is also the same as that described by reference to the preceding figures. Tbe syringe 100, however, includes features not present in syringe 10, previously described by reference to FIGS. 1 through 8.

The syringe 100 includes, at the front section thereof, a barrel 111, the usual plunger 113, provided with a front seal, or sealing head 114, cannula or needle 112 mounted in the forward end of the barrel, and seal 117 which prevents leakage of fluid around the needle annulus. In this instance, the barrel 111 is provided with an opening or cavity 109 of larger diameter than that of the plunger 113, or plunger head 114. A side outlet 108 is located downstream of the said cavity 109.

The rearward portion of syringe 100 comprises a double-acting cylinder piston unit 120, the unit being constituted ofa tubular barrel, of relatively large diameter as contrasted with the forward barrel 111 to which it is affixed, and hermetically separated by a tubular seal 123. The plunger 113 also serves as a piston of the cylinder piston unit and is slidable within the axial opening of the seal 123, the enlarged head portion 118 thereof being contained within the larger diameter tubular barrel 120. The distance over which the plunger 113 is free to move can be preset by virtue of the plunger stop assembly very similar in structure and function to plunger stop assembly 25 described by reference to FIGS. 1 through 8. The plunger stop assembly 125 thus includes a perforated head or stop member 124 rigidly mounted on the forward end of an externally threaded shaft 119, the latter of which is threadably engaged with an internally threaded tubular member 128, rotatably mounted within an axial opening through an end plug 126. The plug 126, it will be noted, is provided with an externally threaded portion of reduced diameter which mates with internal threads inside the end wall of member 120 to which it is firmly secured, and leakage of air around the annulus between the external wall of tubular member 128 and the inside wall forming the axial opening through plug 126 is prevented by an O-ring seal 129. Unlike plunger adjustment stop 25 depicted by reference to FIGS. 1 through 8, however, a helical coil spring 107 encircles the shaft 119 and rotatable tubular member 128, and it is seated and tensioned between the rearward face of perforated head 124 and the forward face of plug 126. Morever, unlike plunger stop assembly 25, the plunger stop assembly 125 is axially displaceable, and with the spring 107 provides an extra function which shall subsequently be described, when actuated in desired se quence by pressurized fluid, e.g., air, introduced into inlet- outlet ports 121, 122.

The syringe 100, containing the enlarged opening or cavity 109, is superior in certain respects to the syringe 10 described by reference to FIGS. 1 through 8, and to the syrine described in copending application Ser. No. 223, 663, supra. It provides better annular flow of the fluid specimen around plunger head 114, such that there is less contamination from previously injected specimens. Better flushing results, and less turbulence is created on withdrawal of the plunger 113. Seal wear is lessened, this resulting not only in a more permanent fit, but also results in less contamination. There is less need for close plunger tolerances, and manufacturing is less complicated.

in operation, referring again to FIG. 9, the plunger 113 is shown in widhdrawn position as pre-set for recipt of a fluid specimen from a vial 82. The vial 82, having been previously pressurized by passage of the opening 65 of probe 51 through chamber 70, transmits fluid via opening 66, the axial opening through the probe, and opening 65 into the opening at the dispensing end of needle 12 to fill the forward end of barrel 111, while the plunger 113 is further withdrawn caused by injection of air via inlet-outlet port 121, with simultaneous venting of inlet-outlet port 122 (FIG. 10). The helical spring is thereby compressed, the tip 114 of plunger 113 is moved back into the enlarged opening or cavity 109 and fluid specimen flows past the tip 114 to purge the needle 12 and forward end of the chamber 111. contaminated fluid egresses via side opening 108, and is passed to waste. On completion of the cleaning purge, inlet-outlet port 121 is vented (FIG. 11) thus releasing the pressure applied upon the forward face of head 118 of plunger 113 so that the latter is thrust forward to trap an accurately measured quantity of fluid specimen forward of the plunger tip 114, which specimen is now ready for injection via steps already described by reference to FIGS. 1 through 8.

Certain modifications can also be made in the injector feed assembly B, in association with changes made in the magazine, or feed mechanism C, to pressurize individual vials via different means than shown by refer ence to the preceding figures, particular reference being made to FIGS. 12 and 13. The injector feed assemblies B described by these figures are thus essentially the same as described by reference to preceding FIGS. 1 through 11, except that pressure chamber 70, with its air inlet port 71, has been completely eliminated. The vials are pressurized by different means.

Referring to FIG. 12, it will be observed that when opeinings 64,65 of probe 51 are aligned with the horizontal opening 53 and drain line 67, and a fluid specimen filled vial 182 constituted of a flexible, elastomeric, plastic or plastic-like material, is positioned by a movable feed tray and the septum 181 thereof pierced by probe 51, a pair of opposed rotating roller members 191,192 with protruding surfaces 193,194 force the walls of the vial 182 inwardly pressurizing the contents of the vial 182 so that the fluid specimen is forced into side opening 66, into the axial opening of probe 51, which fluid exits via opening 65 into the dispensing end of needle 12 (or 112). Reciprocation of the plunger 113 (not shown in this figure) flushes the needle 12 (or 112), discharging the contaminated fluid specimen through line 67, and readies the syringe for injection of an accurately measured fluid specimen.

A slightly different modification of the magazine or feed mechanism is shown by reference to FIG. 13, as contrasted with FIG. 12, although the injector feed assembly B is the same. A fluid specimen filled flexible walled vial 195, of fluted cross section, is herein shown carried on feed magazine, or tray 180. The upper portion of the vial 195 is flanged and fitted within a small diameter opening, and held therein by clamps 196,197. The lower circular portion of the feed tray 180 is open, below the location of the vial, and a hydraulic piston element 198 of a cylinder piston unit 199 can apply force on the bottom of vial 195 to pressurize the fluid therein by squeezing in or collapsing the walls of the septum vial 195. In accordance with this means also, fluid specimen if forced into opening 66 of probe 51, to exit via opening 65 into the dispensing end of needle 12 (or 121). After purging of the excess contaminated fluid specimen via drain line 67, the syringe is ready for injection of an accurately meansured quantity of the specimen.

The injector feed assembly B can be further moditied, and simplified, as shown by reference to FIGS. 14 and 15. Referring to F165. 14 and 15, there is shown another embodiment wherein a pair of hollow probes 151 151,, are mounted within a single movable block 160,, which in effect substantially replaces the upper section 60,, of housing 60, as depicted, e.g., by reference to FIG. 1. The block 160,, containing hollow probes 151 151 is mounted on the terminal end, via appropriate connection (e.g., by threadable engagement), with a reciprocable piston 15hof doubleacting cylinder piston unit 150. Double-acting cylinder piston unit is comprised of the usual barrel, formed by an enclosing side wall 152, enclosing end walls 157i, 157 providing an hermetic seal, and inlet- outlets 161, 162 which admit pressurized fluid, e.g., air, in alternate sequence for impingement on either face of piston head 159 to reciprocate the piston 151C, and consequently the probes 151,,, 151

The lower fixed block 160,; corresponds generally with the lower section 60 of housing 60, as shown by reference to FIG. 1. The fixed block is thus provided with a horizontal opening 153 which is in axial alignment, and open communication, with the passageway leading into the inlet 90 of the analytical instrument, so that an injection of a fluid specimen can be readily made by needle 12, and swept into the instrument by carrier gas admitted via line 91. It will be observed that the axial opening 153, unlike the emobdiments previously described, is in a different plane from the vertical opening 154,, through which the probe 151,, is projected, openings 153, 154,, being communicated one with the other via a short channel 154,,. The second hollow probe 151,,, the upper teminal end of which is connected with a gas inlet 163, is projected through a second vertical opening 154 within block 160 and both probes 151 151 extend through the slot or opening 54 of plate 56.

in operation, air enters via line 161 into cylinder piston unit 150, impinging upon the upper face of piston head 159, driving the piston 151 and consequently the pair of probes 151,,, 151 downwardly, as shown by direct reference to FIG. 14. The probes 151 151,; penetrate the septum 81 of the fluid specimen containing vial 82, positioned by feed tray 80. Air, under pressure, is fed via line 163 through the axial opening of probe 151,;, the air exiting into the vapor space of vial 82 via the side opening 164, building up pressure. Fluid specimen from vial 82 is forced into opening 165 of probe 151,, the fluid rising through the axial opening of probe 151,, and exiting through opening 166, at the upper portion of probe 151,. The fluid specimen then passes through channel 154,, and enters into passageway 153 wherein it is fed into needle 12. On pulsing air via line 162 into the double-acting cylinder piston unit 150, probes 151,, 151 are raised to their uppermost position, in which position opening 165 of probe 151x is in alignment with flush line 167.

A preferred form of this invention is characterized by reference to FIGS. 16 through 19, these figures depicting yet another form of syringe assembly useful in the same overall combination which includes (a) syringe assembly A, (b) injector feed assembly B, and (c) magazine, or feed tray, C as generally described by reference to any of FIGS. 1 through 8, FIGS. 9 through 11, and inclusive also of FIGS. 12 and 13, and FIGS. 14 and 15.

In the syringe 200, depicted by reference to FIGS. 16 through 19, the plunger itself is hollow, providing a dual function serving both as a means for positive expulsion of an accurately measured fluid specimen into, e.g., the inlet of an analytical instrument, and also for conveyance of the fluid specimen through the syringe interior for cleaning and purging of the instrument. Referring generally to the figures, particularly to FIG. 16, it will be observed that the forward portion of the syringe 200 is comprised generally of the usual barrel 211, on the forward terminal end of which is provided a cannula or needle 212, and within the barrel of which is fitted a reciprocable plunger 213; in this instance, however, a hollow plunger. The rearward portion of the barrel 213 is contained within a tubular member 210. Spacer bars 208,209 separate the forward portion of the syringe 200 from a paired series of double-acting cylinder piston units.

Referring to the paired series of double-acting cylinder piston units, it will be observed that the most rear ward double-acting cylinder piston unit 275 includes the usual barrel 276, formed by an enclosing side wall, and enclosing end walls 277,278 with inlet-outlets 279,281 leading into the hermetically sealed enclosure. The forward double-acting cylinder piston unit 250 is also comprised of an enclosing side wall, or barre] 251, with enclosing end walls 252,277, provided with inletoutlet ports 253,254. The end wall 277, it will be noted, provides a common wall between cylinder piston units 250,275. The end wall 277 is provided with an axial opening within which the reciprocable piston 282 is fitted, the piston 282 being affixed to a piston head 283 on which pressurized fluid, e,g., air, acts for reciprocation of the piston on admission of air in alternating sequence via inlet-outlet ports 279,281. The cylinder piston unit 250, it will be observed, is also provided with a hollow piston 255, affixed at one end to piston head 256, this piston 255 also being reciprocable within the axial opening of wall 252 through which it is extended via action of pressurized fluid, e.g., air, admitted in alternate sequence via inlet-outlets 253,254. It will be specifically observed that piston 282 is projected through an axial opening through piston head 256, and an axial opening through hollow piston 255. Each of pistons 255,282 are independently reciprocable, the former being actuated and reciprocated by reciprocated by pressurized gas fed into the unit via lines 279,281.

The rearward end of hollow plunger 213 is externally threaded, and threadably engaged, via an internally threaded central tap within axial opening 215, to the forward end of a slidable tubular member 216. The op posite end of slidable tubular member 216 is also externally threaded and threadably engaged, via an internally threaded cap 217, and affixed nut 218, to the forward terminal end of the externally threaded hollow piston 255. Thus, the tubular member 216 and hollow piston 255 are joined one to the other, or unitized such that movement and reciprocation of hollow piston 255 produces a corresponding movement of tubular memher 216. A section of the rearward side of axial opening 215, of tubular member 216, is enlarged to accomodate an enlarged cylindrical shaped stop 284, located on the forward end of reciprocable piston 282. It will be observed that a segment of reduced diameter, of piston 282, extends forward of the stop 284, and is provided with a sealing head or cap 285. The forward terminal end of hollow plunger 213 is also peripherally sealed by a head or cap 214. In the position shown by reference to FIG. 16, the capped end of plunger 282 blocks the lateral or side opening 219 of tubular member 216.

In operation, referring to FIG. 17, pressurized air is injected via line 286,253,281 into cylinder piston units 250,275, while lines 254,279 are vented, both of pis tons 255,282 being driven to the rear by impingement of air against the inside faces of piston heads 256,283. The rearward movement of piston 255 moves tubular slide 216 to its extreme rearward position, and retracts plunger 213, this occuring as nut 218 impinges against the forward face of end wall 252. The rearward movement of piston 282 withdraws the capped head 285 rearward of lateral opening 219 of tubular slide 216 so that a fluid specimen is drawn via needle 212 into barrel 211, the fluid specimen passing through the axial opening of hollow plunger 213 and discharging through the lateral opening 219 of slide 216. The rearward movement of plunger 282 is terminated on contact of stop 284 with the inside face of cap 217.

Upon completion of the purging and cleaning step, pressurized air is injected via line 279, into cylinder piston unit 275, at pressure slightly greater than that introduced into the cylinder piston unit 275 via line 281, the air impinging on the rearward face of plunger head 283, pushing the plunger 283 forward a limited amount until the stop 284 is seated, and its forward motion blocked, against the forward wall of the enlarged portion of axial opening 215, at which time the tip of the capped head 285 of plunger 282 abutts the rearward end of plunger 213. The flow of fluid specimen through needle 212, barrel 211, plunger 213, and into lateral opening 219 is thus abated. At this time, the needle 212 of syringe 200 is inserted into the inlet of an analytical instrument, e.g., inlet 90, in the same manner described by reference to the preceding figures.

To effect injection of the accurately measured fluid specimen, pressurized air is admitted via line 254, 279, while lines 253, 281, 286 are vented, such that the tubular slide 216, and hollow plunger 213 are driven forward to expel the fluid specimen via needle 212.

It is apparent that various substitutions, modifications and changes, such as in location, or in the absolute or relative dimensions of the parts, materials used and the like, can be made without departing the spirit and scope of the invention as will be apparent to those skilled in the art.

Having described the invention, what is claimed is:

1. In apparatus for repetitively accurately measuring and injecting preselected quantities of fluid specimens into a media such as an inlet to an analytical instrument, the combination comprising a housing, which can be mounted adjacent an inlet leading into the analytical instrument,

a tubular member located within the housing, said tubular member including a pair of communicated openings therethrough, a first opening of the pair extending through the tubular member and housing, a second axial opening adjacent to and communicated with the said first opening which can be aligned upon the inlet leading into the analytical instrument,

a needle syringe mounted upon the forward end of a piston of a cylinder-piston unit affixed upon the housing, said syringe including a barrel, including forward and rearward tubular portions, formed by an enclosing wall defining an axial opening,

a chamber of substantially cylindrical-shaped cross section located at the front end of the forward portion of the barrel,

an enlarged chamber opening communicating with and located rearward of the said chamber,

an outlet located within the forward portion of the barrel, rearward of the enlarged chamber opening,

a hollow needle, provided with an opening in the dispensing end thereof, mounted at the forward end of the barrel, the opening through said needle communicating with the axial opening through the barrel,

a reciprocable plunger mounted within the barrel, said plunger including a forward portion fitted snugly within the chamber of substantially cylindrical-shaped cross section located at the forward end of the barrel and a rearward portion provided with an enlarged head of cross-section corresponding substantially with the crosssection of the rearward portion of the barrel within and through which the head moves on reciprocation of the plunger,

a seal located within and separating the forward and rearward portions of said barrel, the plunger being extended therethrough and reciprocable therein such that the head of the plunger traverses the rearward tubular portion of the barrel and the forward portion of the plunger traverses the forward portion of the barrel,

a plunger adjustment assembly located within the rearward portion of the barrel, within the path of travel of said plunger, wherein is included an end plug which fits within and encloses the rearward portion of said barrel, and a pair of telescoping members located forward of the said enclosing end plug, and means whereby the pair of telescoping sections can be lengthened or shortened in an axial direction along the length of the rearward tubular portion of the barrel such that the distance travelled by the reciprocable plunger can be preset as desired,

means provided within the rearward tubular portion of the barrel for reciprocation of the plunger,

an injector feed unit including a hollow probe provided with communicating upper and lower side openings mounted on the forward end of a piston of a cylinder-piston unit affixed upon the housing, said probe being aligned upon the said first opening of the tubular member within and through which the probe can be reciprocated by movement of the piston, and extended through the said first opening, and

means for transporting a fluid specimen containing a vial, with a septum cap, below the said first opening and into the path of the hollow probe for penetration of the septum for pick-up of the fluid specimen via the lower side opening of the probe and conveyance of same via the upper opening of the probe, through the communication connecting the first and second openings, and into the opening within the dispensing end of the needle and into the cylindrical-shaped chamber in the forward barrel portion of the syringe, which fluid specimen can flow therethrough to the enlarged chamber outlet located within the forward portion of the barrel, and a predetermined quantity of fluid specimen can be trapped and accurately measured within the forward barrel portion of the syringe by forward movement of the tip of the plunger past the outlet and enlarged chamber located within the forward portion of the barrel, the needle of the needle syringe then thrust through the said second opening of the tubular member and into the inlet to the analytical instrument, and the accurately measured quantity of fluid specimen injected into the inlet by continued forward movement of the plungerv 2. The apparatus of claim 1 wherein the forward and rearward portions of the syringe barrel are constituted of two separate tubular members, a small-diameter forward tubular member, within which is provided the cylindrrical shaped forward chamber, enlarged chamber outlet and side opening, and within the forward portion of which the hollow needle is sealed, and a rearward larger-diameter tubular member, the wall of which is provided with forward and rearward inlet-outlet ports for ingress and egress of pressurized fluid which impinges on the head of the plunger, which lies therein, for reciprocation of the plunger, the plunger being fitted through a seal located between the said forward and rearward tubular members such that the forward portion of the plunger traverses the forward tubular member while the head of the piston traverses the rearward tubular member.

3. The apparatus of claim 1 wherein the plunger adjustment assembly, which is located within the rearward portion of the barrel, and includes an end plug which fits within and encloses the rearward portion of said barrel, is comprised of outer and inner telescoping members fitted through said end plug,

a shaft extendeed from the outer telescoping member which is fitted through an opening within the said plug portion,

an enlarged perforated head located on the forward end of said shaft against the forward face of which the head of the plunger can impinge, and the A tubular section, the forward end of which provides a stop surface against which the perforated head of the shaft can impinge on rearward contact by the plunger, and which, in combination with said enlarged head and shaft, provides telescoping members which can be lengthened or shortened in an axial direction along the length of the rearward tubular portion of the barrel, the said plunger adjustment assembly including a helical spring fitted concentrically about the said tubular section, enlarged head and shaft and seated between the rearward face of the enclosed end of the said tubular section and the forward face of the plug portion sealing the rearward portion of said barrel.

4. The apparatus of claim 1 wherein the cylinderpiston unit of the injector feed unit is a double-acting cylindenpiston unit comprising a barrel within which pressuril'cd fluid can be admitted or expelled \iu inletoutlet ports located on opposite sides of the area oftramm: of the enlarged head affixed upon an end of the piston of the cylinder-piston unit. the probe constitutes the piston ofthe cylinderpiston unit in that it is directly affixed via one of its terminal ends to an enlarged head and reciprocable therewith when acted upon by ingress and egress of pressurized fluid admitted or expelled \ia the said inlet-outlet ports 5. In an apparatus for repetitively accurately measuring and injecting preselected quantities of fluid specimens into a media such as an inlet to an analytical instrument, the combination comprising a housing. which can be mounted adjacent an inlet leading into the analytical instrument,

a tubular member located within the housing, said tubular member including a pair of communicated openings therethrough. a first opening of the pair extending through the tubular member and housing. a second opening adjacent to and communicated with the first opening which can be aligned upon the inlet leading into the analytical instrumerit,

a needle syringe mounted upon the forward end of a piston of a cylinder-piston unit affixed upon the housing, said syringe including a barrel. including forward and rearward tubular portions, formed by an enclosing wall defining an axial opening,

a hollow needle. provided with an opening in the dispensing end thereof, mounted at the forward end of the barrel. the opening through the said needle communicating with the axial opening through the barrel,

a reciprocable plunger mounted within the barrel, said plunger including a forward portion fitted snugly within the axial opening within the forward portion of said barrel and a rearward portion provided with an enlarged head of crosssection corresponding substantially with the cross-section of the rearward portion of the barrel within which the head moves on reciprocation of the plunger,

a seal located within and separating the forward and rearward portions of said barrel. the plunger being extended therethrough and reciprocable therein such that the head of the plunger traverses the rearward tubular portion of the barrel and the forward portion of the plunger traverses the forward portion of the barrel,

a plunger adjustment assembly located within the rearward portion of the barrel. within the path of travel of said plunger. wherein is included a plug which fits within and encloses the rearward por tion of said barrel. and a pair of telescoping sections located forward of the said enclosing plug. such that the pair of telescoping sections can be lengthened or shortened in an axial direction along the length of the rearward tubular portion of the barrel to preset the distance travelled by the plunger,

inlet-outlet ports located at opposite ends of the rearward tubular portion of the barrel through \ihich a pressurized fluid can be injected for reciprocation of the plunger.

an injector feed unit including a pair of hollow probes. each of which are provided with upper an lower openings. mounted on the forward end of a piston of a cylinder-piston unit affixed upon the housing. pressurized fluid inlet means associated with an upper opening of one of the pair of probes. said probes being aligned upon the said first opening through the tubular member within and through which the probes can be reciprocatcd by movement of the piston. and extended through the said first opening, and

means for transporting a fluid specimen containing a vial. with a resilient puncturable septum cap, below the said first opening and within the path of the pair of hollow probes for penetration of the septum cap by the probes, whereby pressurized fluid injected into the vial by one of the pair of probes pressurizes the fluid contents of the vial so that the fluid contents of the vial can be forced into a lower opening of the opposite probe of the pair and conveyed through the axial opening, and through an upper opening into the needle and into the forward tubu lar barrel portion of the syringe.

6. In apparatus for repetitively accurately measuring and injecting preselected quantities of fluid specimens into a media such as an inlet to an analytical instrument. the combination comprising a housing. which can be mounted adjacent an inlet leading into the anaytical instrument,

a tubular member located within the housing. said tubular member including a pair of communicated openings therethrough, a first opening of the pair extending through the tubular member and housing. a second opening adjacent to and communicated with the said first opening which can be aligned upon the inlet leading into the analytical instrument,

a needle syringe mounted upon the forward end of a piston of a cylinder-piston unit affixed upon the housing, said syringe including a barrel, including forward and rearward tubular portions, formed by an enclosing wall defining an axial opening,

hollow needle, provided with an opening in the dispensing end thereof, mounted at the forward end of the barrel. the opening through the said needle communicating with the axial opening through the barrel,

a tubular flange closing the opposite end of the barrel.

a hollow reciprocable plunger mounted within the barrel, said plunger including a forward portion fitted snugly within the axial opening through the end of the barrel, and a rearward portion which extends through the axial opening within the enclosing tubular flange.

a pair of serially connected double-acting cylinderpiston units. a rearward double-acting cylinderpiston unit including a barrel, an enclosing rearward end wall and a tubular forward end wall, a reciprocable piston the shaft portion of which is fitted within and projected through the axial opening of the tubular forward end wall and the enlarged head of which is located within the said barrel. and inlet-outlet ports located at opposite ends of said barrel for admission of pressurized fluid for reciprocation of the piston, and a forward double-acting cylinder-piston unit including a barrel the rearward end of which is enopening of the pair extending through the tubular member, said chamber and housing, and a second opening adjacent to and communicated with said first axial opening which can be aligned upon the closed by the tubular forward end wall of said inlet leading into the analytical instrument, rearward double-acting cylinder-piston unit, a a needle syringe mounted upon a piston ofa cylinderforward enclosing tubular end wall, a reciprocapiston unit affixed upon the housing, the needle of ble hollow piston the shaft portion of which is fitwhich is aligned upon said second opening through ted within and projected through the axial openthe tubular member within and through which the ing of the tubular forward enclosing end wall and needle can be reciprocated by movement of the the enlarged tubular head of which is fitted piston, said syringe including a barrel comprised of within the said barrel, the shaft of the piston unit forward and rearward tubular portions separated being fitted and slidable within the axial opening one from the other by sealing means. the forward through said reciprocable hollow piston, the said tubular portion of said syringe providing a chamber forward double-acting cylinder-piston unit also l5 for containing a predetermined quantity of fluid for including inlet-outlet ports for admission of presinjection via an opening within the dispensing end surized fluid for reciprocation of said hollow pisof the needle which is mounted on the front end of ton, the said forward tubular portion, the rearward tua tubular member, provided with a lateral opening, bular portion of said syringe containing a plunger, movable between the tubular flange closing the 20 the front end of which can be reciprocated within end of the barrel of the syringe and the forward the chamber in the forward portion of the syringe, tubular end wall which encloses the forward douthe plunger providing in its retracted position a ble-acting cylinder-piston unit, separated one chamber which can be filled with fluid in predeterfrom the other by spacing support bars, the holmined quantity from the dispensing end of the neelow plunger of the syringe barrel being affixed to dle which, on subsequent forward thrust of the said tubular member at one end and in axial complunger, the fluid specimen can be injected through munication therewith and with the said lateral the dispensing end of the needle, opening, the hollow piston of the forward douan injector feed assembly including a hollow probe ble-acting cylinder-piston unit being affixed the provided with communicating upper and lower opposite end of said tubular member, and in axial 3O openings mounted on the forward end of the piston communication with said axial opening through of a cylinder-piston unit affixed upon the housing, the movable tubular member such that the piston said probe being aligned upon the said first axial shaft of said rearward double-acting cylinderopening through the tubular member within and piston unit can be reciprocated therethrough to through which the probe can be reciprocated by open the lateral opening to communication with movement of the piston, and extended through the the dispensing end of the needle or close off such said first axial opening, communication by closure of the lateral opening means for transporting a fluid specimen contained in and rearward end of the hollow plunger, a vial, with a resilient, puncturable closure, below an injector feed assembly including a hollow probe the said first axial opening and into the path of the provided with communicating upper and lower hollow probe for penetration of said closure by the openings mounted on the forward end of the piston probe, of a cylinder-piston unit affixed upon the housing, whereby pressurized gas can be injected via its inlet said probe being aligned upon the said first axial into said hermetically sealed chamber on alignment opening through the tubular member within and of the upper probe opening with said chamber and through which the probe can be reciprocated by the fluid contents ofthe vial pressurized by delivery movement of the piston, and extended through the of the gas into the vial via passage through the said first axial opening, probe, on discontinuance of the alignment of said means for transporting a fluid specimen contained in upper probe opening with the pressurized hermetia vial, with a resilient, puncturable closure, below cally sealed chamber which occurs by the downthe said first axial opening and into the path of the ward movement of the probe the applied gas preshollow probe for penetration of said closure by the sure is discontinued, and after entry of the lower probe, and probe opening into the fluid contents of the vial, a means for pressurizing the fluid contents of the vial fluid specimen contained within the vial can be so that the fluid specimen contained within the vial transferred via the probe into the opening of the can be transferred via the lower and upper side openings of the probe into the opening of the needle and into the chamber of the syringe.

7. ln apparatus for repetitively accurately measuring needle and into the chamber of the syringe.

8. The apparatus of claim 7 wherein the rearward tubular portion constituting the barrel of said needle syringe comprises a double-acting cylinder piston unit which includes forward and rearward inlet-outlet ports and injecting preselected quantities of fluid specimens into a media such as an inlet to an analytical instrument, the combination comprising a housing, which can be mounted adjacent an inlet leading into the analytical instrument,

a tubular member mounted within the housing, said tubular member including an inner hermetically sealed chamber and a gas inlet to said chamber and a pair of communicated openings, a first axial 0 through which pressurized fluid can be admitted to reciprocate the piston, the piston is also the plunger of the forward portion of the syringe, and the rearward tubular portion of said syringe constituting the doubleacting cylinder piston unit includes a plunger adjustment assembly comprising an end plug of relative large cross-section located within and enclosing the rearward wall of the cylinder piston unit, and a pair of telescop-

Claims (21)

1. In apparatus for repetitively accurately measuring and injecting preselected quantities of fluid specimens into a media such as an inlet to an analytical instrument, the combination comprising a housing, which can be mounted adjacent an inlet leading into the analytical instrument, a tubular member located within the housing, said tubular member including a pair of communicated openings therethrough, a first opening of the pair extending through the tubular member and housing, a second axial opening adjacent to and communicated with the said first opening which can be aligned upon the inlet leading into the analytical instrument, a needle syringe mounted upon the forward end of a piston of a cylinder-piston unit affixed upon the housing, said syringe including a barrel, including forward and rearward tubular portions, formed by an enclosing wall defining an axial opening, a chamber of substantially cylindrical-shaped cross section located at the front end of the forward portion of the barrel, an enlarged chamber opening communicating with and located rearward of the said chamber, an outlet located within the forward portion of the barrel, rearward of the enlarged chamber opening, a hollow needle, provided with an opening in the dispensing end thereof, mounted at the forward end of the barrel, the opening through said needle communicating with the axial opening through the barrel, a reciprocable plunger mounted within the barrel, said plunger including a forward portion fitted snugly within the chamber of substantially cylindrical-shaped cross section located at the forward end of the barrel and a rearward portion provided with an enlarged head of cross-section corresponding substantially with the cross-section of the rearward portion of the barrel within and through which the head moves on reciprocation of the plunger, a seal located within and separating the forward and rearward portions of said barrel, the plunger being extended therethrough and reciprocable therein such that the head of the plunger traverses the rearward tubular portion of the barrel and the forward portion of the plunger traverses the forward portion of the barrel, a plunger adjustment assembly located within the rearward portion of the barrel, within the path of travel of said plunger, wherein is included an end plug which fits within and encloses the rearward portion of said barrel, and a pair of telescoping members located forward of the said enclosing end plug, and means whereby the pair of telescoping sections can be lengthened or shortened in an axial direction along the length of the rearward tubular portion of the barrel such that the distance travelled by the reciprocable plunger can be preset as desired, means provided within the rearward tubular portion of the barrel for reciprocation of the plunger, an injector feed unit including a hollow probe provided with communicating upper and lower side openings mounted on the forward end of a piston of a cylinder-piston unit affixed upon the housing, said probe being aligned upon the said first opening of the tubular member within and through which the probe can be reciprocated by movement of the piston, and extended through the said first opening, and means for transporting a fluid specimen containing a vial, with a septum cap, below the said first opening and into the path of the hollow probe for penetration of the septum for pick-up of the fluid specimen via the lower side opening of the probe and conveyance of same via the upper opening of the probe, through the communication connecting the first and second openings, and into the opening within the dispensing end of the needle and into the cylindrical-shaped chamber in the forward barrel portion of the syringe, which fluid specimen can flow therethrough to the enlarged chamber outlet located within the forward portion of the barrel, and a predetermined quantity of fluid specimen can be trapped and accurately measured within the forward barrel portion of the syringe by forward movement of the tip of the plunger past the outlet and enlarged chamber located within the forward portion of the barrel, the needle of the needle syringe then thrust through the said second opening of the tubular member and into the inlet to the analytical instrument, and the accurately measured quantity of fluid specimen injected into the inlet by continued forward movement of the plunger.

2. The apparatus of claim 1 wherein the forward and rearward portions of the syringe barrel are constituted of two separate tubular members, a small-diameter forward tubular member, within which is provided the cylindrrical shaped forward chamber, enlarged chamber outlet and side opening, and within the forward portion of which the hollow needle is sealed, and a rearward larger-diameter tubular member, the wall of which is provided with forward and rearward inlet-outlet ports for ingress and egress of pressurized fluid which impinges on the head of the plunger, which lies therein, for reciprocation of the plunger, the plunger being fitted through a seal located between the said forward and rearward tubular members such that the forward portion of the plunger traverses the forward tubular member while the head of the piston traverses the rearward tubular member.

3. The apparatus of claim 1 wherein the plunger adjustment assembly, which is located within the rearward portion of the barrel, and includes an end plug which fits within and encloses the rearward portion of said barrel, is comprised of outer and inner telescoping members fitted through said end plug, a shaft extendeed from the outer telescoping member which is fitted through an opening within the said plug portion, an enlarged perforated head located on the forward end of said shaft against the forward face of which the head of the plunger can impinge, and the A tubular section, the forward end of which provides a stop surface against which the perforated head of the shaft can impinge on rearward contact by the plunger, and which, in combination with said enlarged head and shaft, provides telescoping members which can be lengthened or shortened in an axial direction along the length of the rearward tubular portion of the barrel, the said plunger adjustment assembly including a helical spring fitted concentrically about the said tubular section, enlarged head and shaft and seated between the rearward face of the enclosed end of the said tubular section and the forward face of the plug portion sealing the rearward portion of said barrel.

4. The apparatus of claim 1 wherein the cylinder-piston unit of the injector feed unit is a double-acting cylinder-piston unit comprising a barrel within which pressurized fluid can be admitted or expelled via inlet-outlet ports located on opposite sides of the area of traverse of the enlarged head affixed upon an end of the piston of the cylinder-piston unit, the probe constitutes the piston of the cylinder-piston unit in that it is directly affixed via one of its terminal ends to an enlarged head and reciprocable therewith when acted upon by ingress and egress of pressurized fluid admitted or expelled via the said inlet-outlet ports. 5. In an apparatus for repetitively accurately measuring and injecting preselected quantities of fluid specimens into a media such as an inlet to an analytical instrument, the combination comprising a housing, which can be mounted adjacent an inlet leading into the analytical instrument, a tubular member located within the housing, said tubular member including a pair of communicated openings therethrough, a first opening of the pair extEnding through the tubular member and housing, a second opening adjacent to and communicated with the first opening which can be aligned upon the inlet leading into the analytical instrument, a needle syringe mounted upon the forward end of a piston of a cylinder-piston unit affixed upon the housing, said syringe including a barrel, including forward and rearward tubular portions, formed by an enclosing wall defining an axial opening, a hollow needle, provided with an opening in the dispensing end thereof, mounted at the forward end of the barrel, the opening through the said needle communicating with the axial opening through the barrel, a reciprocable plunger mounted within the barrel, said plunger including a forward portion fitted snugly within the axial opening within the forward portion of said barrel and a rearward portion provided with an enlarged head of cross-section corresponding substantially with the cross-section of the rearward portion of the barrel within which the head moves on reciprocation of the plunger, a seal located within and separating the forward and rearward portions of said barrel, the plunger being extended therethrough and reciprocable therein such that the head of the plunger traverses the rearward tubular portion of the barrel and the forward portion of the plunger traverses the forward portion of the barrel, a plunger adjustment assembly located within the rearward portion of the barrel, within the path of travel of said plunger, wherein is included a plug which fits within and encloses the rearward portion of said barrel, and a pair of telescoping sections located forward of the said enclosing plug, such that the pair of telescoping sections can be lengthened or shortened in an axial direction along the length of the rearward tubular portion of the barrel to preset the distance travelled by the plunger, inlet-outlet ports located at opposite ends of the rearward tubular portion of the barrel through which a pressurized fluid can be injected for reciprocation of the plunger, an injector feed unit including a pair of hollow probes, each of which are provided with upper an lower openings, mounted on the forward end of a piston of a cylinder-piston unit affixed upon the housing, pressurized fluid inlet means associated with an upper opening of one of the pair of probes, said probes being aligned upon the said first opening through the tubular member within and through which the probes can be reciprocated by movement of the piston, and extended through the said first opening, and means for transporting a fluid specimen containing a vial, with a resilient puncturable septum cap, below the said first opening and within the path of the pair of hollow probes for penetration of the septum cap by the probes, whereby pressurized fluid injected into the vial by one of the pair of probes pressurizes the fluid contents of the vial so that the fluid contents of the vial can be forced into a lower opening of the opposite probe of the pair and conveyed through the axial opening, and through an upper opening into the needle and into the forward tubular barrel portion of the syringe.

6. In apparatus for repetitively accurately measuring and injecting preselected quantities of fluid specimens into a media such as an inlet to an analytical instrument, the combination comprising a housing, which can be mounted adjacent an inlet leading into the anaytical instrument, a tubular member located within the housing, said tubular member including a pair of communicated openings therethrough, a first opening of the pair extending through the tubular member and housing, a second opening adjacent to and communicated with the said first opening which can be aligned upon the inlet leading into the analytical instrument, a needle syringe mounted upon the forward end of a piston of a cylinder-piston unit affixed upon the housing, said syringe including a barrel, including forward and rearward tubular portions, Formed by an enclosing wall defining an axial opening, a hollow needle, provided with an opening in the dispensing end thereof, mounted at the forward end of the barrel, the opening through the said needle communicating with the axial opening through the barrel, a tubular flange closing the opposite end of the barrel, a hollow reciprocable plunger mounted within the barrel, said plunger including a forward portion fitted snugly within the axial opening through the end of the barrel, and a rearward portion which extends through the axial opening within the enclosing tubular flange, a pair of serially connected double-acting cylinder-piston units, a rearward double-acting cylinder-piston unit including a barrel, an enclosing rearward end wall and a tubular forward end wall, a reciprocable piston the shaft portion of which is fitted within and projected through the axial opening of the tubular forward end wall and the enlarged head of which is located within the said barrel, and inlet-outlet ports located at opposite ends of said barrel for admission of pressurized fluid for reciprocation of the piston, and a forward double-acting cylinder-piston unit including a barrel the rearward end of which is enclosed by the tubular forward end wall of said rearward double-acting cylinder-piston unit, a forward enclosing tubular end wall, a reciprocable hollow piston the shaft portion of which is fitted within and projected through the axial opening of the tubular forward enclosing end wall and the enlarged tubular head of which is fitted within the said barrel, the shaft of the piston unit being fitted and slidable within the axial opening through said reciprocable hollow piston, the said forward double-acting cylinder-piston unit also including inlet-outlet ports for admission of pressurized fluid for reciprocation of said hollow piston, a tubular member, provided with a lateral opening, movable between the tubular flange closing the end of the barrel of the syringe and the forward tubular end wall which encloses the forward double-acting cylinder-piston unit, separated one from the other by spacing support bars, the hollow plunger of the syringe barrel being affixed to said tubular member at one end and in axial communication therewith and with the said lateral opening, the hollow piston of the forward double-acting cylinder-piston unit being affixed the opposite end of said tubular member, and in axial communication with said axial opening through the movable tubular member such that the piston shaft of said rearward double-acting cylinder-piston unit can be reciprocated therethrough to open the lateral opening to communication with the dispensing end of the needle or close off such communication by closure of the lateral opening and rearward end of the hollow plunger, an injector feed assembly including a hollow probe provided with communicating upper and lower openings mounted on the forward end of the piston of a cylinder-piston unit affixed upon the housing, said probe being aligned upon the said first axial opening through the tubular member within and through which the probe can be reciprocated by movement of the piston, and extended through the said first axial opening, means for transporting a fluid specimen contained in a vial, with a resilient, puncturable closure, below the said first axial opening and into the path of the hollow probe for penetration of said closure by the probe, and means for pressurizing the fluid contents of the vial so that the fluid specimen contained within the vial can be transferred via the lower and upper side openings of the probe into the opening of the needle and into the chamber of the syringe.

7. In apparatus for repetitively accurately measuring and injecting preselected quantities of fluid specimens into a media such as an inlet to an analytical instrument, the combination comprising a housing, which can be mounted adjacent an inlet leading into the analytical instrument, a tubular member mounted within the housing, said tubular member including an inner hermetically sealed chamber and a gas inlet to said chamber and a pair of communicated openings, a first axial opening of the pair extending through the tubular member, said chamber and housing, and a second opening adjacent to and communicated with said first axial opening which can be aligned upon the inlet leading into the analytical instrument, a needle syringe mounted upon a piston of a cylinder-piston unit affixed upon the housing, the needle of which is aligned upon said second opening through the tubular member within and through which the needle can be reciprocated by movement of the piston, said syringe including a barrel comprised of forward and rearward tubular portions separated one from the other by sealing means, the forward tubular portion of said syringe providing a chamber for containing a predetermined quantity of fluid for injection via an opening within the dispensing end of the needle which is mounted on the front end of the said forward tubular portion, the rearward tubular portion of said syringe containing a plunger, the front end of which can be reciprocated within the chamber in the forward portion of the syringe, the plunger providing in its retracted position a chamber which can be filled with fluid in predetermined quantity from the dispensing end of the needle which, on subsequent forward thrust of the plunger, the fluid specimen can be injected through the dispensing end of the needle, an injector feed assembly including a hollow probe provided with communicating upper and lower openings mounted on the forward end of the piston of a cylinder-piston unit affixed upon the housing, said probe being aligned upon the said first axial opening through the tubular member within and through which the probe can be reciprocated by movement of the piston, and extended through the said first axial opening, means for transporting a fluid specimen contained in a vial, with a resilient, puncturable closure, below the said first axial opening and into the path of the hollow probe for penetration of said closure by the probe, whereby pressurized gas can be injected via its inlet into said hermetically sealed chamber on alignment of the upper probe opening with said chamber and the fluid contents of the vial pressurized by delivery of the gas into the vial via passage through the probe, on discontinuance of the alignment of said upper probe opening with the pressurized hermetically sealed chamber which occurs by the downward movement of the probe the applied gas pressure is discontinued, and after entry of the lower probe opening into the fluid contents of the vial, a fluid specimen contained within the vial can be transferred via the probe into the opening of the needle and into the chamber of the syringe.

8. The apparatus of claim 7 wherein the rearward tubular portion constituting the barrel of said needle syringe comprises a double-acting cylinder piston unit which includes forward and rearward inlet-outlet ports through which pressurized fluid can be admitted to reciprocate the piston, the piston is also the plunger of the forward portion of the syringe, and the rearward tubular portion of said syringe constituting the double-acting cylinder piston unit includes a plunger adjustment assembly comprising an end plug of relative large cross-section located within and enclosing the rearward wall of the cylinder piston unit, and a pair of telescoping members located forward of the enclosing end plug, and means whereby the pair of telescoping sections can be lengthened or shortened in an axial direction along the length of the rearward tubular portion of the syringe such that the distance within which the plunger of the double-acting cylinder piston unit is free to travel can be preset, as desired.

9. The apparatus of claim 7 wherein the forward portion of the barrel of the needle syringe mounted on the piston of a cylinder-piston unit is provided with a side opening such that Fluid transferred from the vial through the probe can be passed in a stream through the chamber to exit via the side opening therefrom, thereafter a predetermined amount of a fluid specimen can be trapped for subsequent delivery by limited forward movement of the plunger which blocks said side opening, and thereafter the needle of the needle syringe can be thrust through said second opening of the tubular member and into the inlet to the analytical instrument, and the accurately measured quantity of fluid specimen injected into the inlet by continued forward movement of the plunger.

10. The apparatus of claim 7 wherein the needle syringe mounted on the piston of the cylinder-piston unit is one which comprises a barrel, including forward and rearward tubular portions, formed by an enclosing wall defining an axial opening, a chamber of substantially cylindrical-shaped cross-section located at the front end of the forward portion of the barrel, an enlarged chamber opening communicating with and located rearward of the said chamber, an outlet located within the forward portion of the barrel, rearward of the enlarged chamber opening, a hollow needle, provided with an opening in the dispensing end thereof, mounted at the forward end of the barrel, the opening through said needle communicating with the axial opening through the barrel, a reciprocable plunger mounted within the barrel, said plunger including a forward portion fitted snugly within the chamber of substantially cylindrical-shaped cross-section located at the forward end of the barrel and a rearward portion provided with an enlarged head of cross-section corresponding substantially with the cross-section of the rearward portion of the barrel within and through which the head moves on reciprocation of the plunger, a seal located within and separating the forward and rearward portions of said barrel, the plunger being extended therethrough and reciprocable therein such that the head of the plunger traverses the rearward tubular portion of the barrel and the forward portion of the plunger traverses the forward portion of the barrel.

11. The apparatus of claim 10 wherein the syringe includes a plunger adjustment assembly located within the rearward portion of the barrel, within the path of travel of said plunger, wherein is included an end plug which fits within and encloses the rearward portion of said barrel, and a pair of telescoping members located forward of the said enclosing end plug, and means whereby the pair of telescoping sections can be lengthened or shortened in an a axial direction along the length of the rearward tubular portion of the barrel such that the distance travelled by the reciprocable plunger can be preset as desired.

12. In apparatus for repetitively accurately measuring and injecting preselected quantities of fluid specimens into a media such as an inlet to an analytical instrument, the combination comprising a housing, which can be mounted adjacent an inlet leading into the analytical instrument, a tubular member mounted within the housing, said tubular member including a pair of communicated openings therethrough, a first axial opening of the pair extending through the tubular member and housing, and a second opening adjacent to and communicated with said first axial opening which can be aligned upon the inlet leading into the analytical instrument, a needle syringe mounted upon the forward end of a piston of a cylinder-piston unit affixed upon the housing, the needle of which is aligned upon said second opening through the tubular member within and through which the needle can be reciprocated by movement of the piston, said syringe including a barrel comprised of forward and rearward tubular portions separated one from the other by sealing means, the forward tubular portion of said syringe providing a chamber of substantially cylindrical-shaped cross section located at the front end of the forward portion of the barrel for cOntaining a predetermined quantity of fluid for injection via an opening within the dispensing end of the needle which is mounted on the front end of the said forward tubular portion, an enlarged chamber opening communicating with and located rearward of the said chamber, an outlet located within the forward portion of the barrel, rearward of the enlarged chamber opening, the rearward tubular portion of said syringe containing a plunger, the front end of which can be reciprocated within the chamber in the forward portion of the syringe, the plunger providing, in a retracted position a channel for flow of fluid from the dispensing end of the needle through the chamber, enlarged chamber opening, and outlet located within the forward portion of the barrel, and in a forward position wherein the forward end of the plunger is located in front of said enlarged chamber opening, a closed chamber wherein a fluid specimen can be contained in predetermined quantity, and on subsequent forward thrust of the needle of the syringe into the inlet of the analytical instrument the fluid specimen can be injected through the dispensing end of the needle, an injector feed assembly including a hollow probe provided with communicating upper and lower openings mounted on the forward end of the piston of a cylinder-piston unit affixed upon the housing, said probe being aligned upon the said first axial opening through the tubular member within and through which the probe can be reciprocated by movement of the piston, and extended through the said first axial opening, means for transporting a fluid specimen contained in a vial, with a resilient, puncturable closure, below the said first axial opening and into the path of the hollow probe for penetration of said closure by the probe, and means for pressurizing the fluid contents of the vial so that the fluid specimen contained within the vial can be transferred via the lower and upper side openings of the probe into the opening of the needle and into the chamber of the syringe.

13. The apparatus of claim 12 wherein the tubular member mounted within the housing and containing the pair of communicated openings is provided within an internal enlarged hermetically sealed chamber, said chamber being provided with fluid inlet means, such that an upper opening within the hollow probe, which is fitted and traversable within the said first axial opening of the tubular member, and a lower probe opening are in communication via the opening through the hollow probe, at such time the upper probe opening is located within said chamber a pressurized fluid can be transmitted through the hollow probe to a vial to pressurize the fluid specimen contained therein for transfer via the probe to the needle opening and into the chamber of the syringe.

14. The apparatus of claim 12 wherein the cylinder-piston unit of the injector feed unit is a double-acting cylinder-piston unit comprising a barrel within which pressurized fluid can be admitted or expelled via inlet-outlet ports located on opposite sides of the area of traverse of the enlarged head affixed upon an end of the piston of the cylinder-piston unit, the probe constitutes the piston of the cylinder-piston unit in that it is directly affixed via one of its terminal ends to an enlarged head and reciprocable therewith when acted upon by ingress and egress of pressurized fluid admitted or expelled via the said inlet-outlet ports to the said first tubular member.

15. The apparatus of claim 13 wherein the hermetically sealed chamber is formed between an abutting pair of tubular sections of cylindrical shape, and a tubular shaped bushing is fitted concentrically therein to seal the interface between the abutting upper and lower tubular sections.

16. The apparatus of claim 13 wherein the pair of communicated openings of the said tubular member intersect, and are located within the same plane.

17. The apparatus of claim 12 wherein the means for pressurizing the fluid contents of a vial are comprised of An opposed pair of rollers, with projections, which compress the walls of a vial, a vial in this instance being constituted of a flexible material.

18. The apparatus of claim 12 wherein the means for pressurizing the fluid contents of a vial are comprised of the piston of a cylinder-piston unit which compresses the walls of a vial, a vial in this instance being provided with an enclosing wall of fluted cross-section and constituted of a flexible material.

19. The apparatus of claim 12 wherein the rearward tubular portion constituting the barrel of said needle syringe comprises a double-acting cylinder piston unit, the piston of which is also the plunger of the forward portion of the syringe.

20. The apparatus of claim 19 wherein the rearward tubular portion of said syringe constituting the double-acting cylinder piston unit includes forward and rearward inlet-outlet ports through which pressurized fluid can be admitted to reciprocate the piston.

21. The apparatus of claim 20 wherein the rearward tubular portion of said syringe constituting the double-acting cylinder piston unit includes a plunger adjustment assembly comprising an end plug of relative large cross section located within and enclosing the rearward wall of the cylinder-piston unit, and a pair of telescoping members located forward of the enclosing end plug, and means whereby the pair of telescoping sections can be lengthened or shortened in an axial direction along the length of the rearward tubular portion of the syringe such that the distance within which the plunger of the double-acting cylinder piston unit is free to travel can be preset, as desired.

22. The apparatus of claim 21 wherein the end plug is tubular and provided with an externally threaded projection, threadably engaged to internal threads located within the rearward wall of the cylinder piston unit, and the telescoping members include a rotatable member, of tubular design, mounted within the axial opening thereof and is internally threaded, and a shaft provided with the enlarged forward head is externally threaded and threadably engaged within the rotatable tubular member such that rotation of the rotatable member provides the telescoping action which lengthens or shortens the distance that the plunger is free to travel.

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