US2695612A - Hypodermic syringe - Google Patents

Description

M. R. FIELDS HYPODERMIC SYRINGE Nov. 30, 1954 2 Sheets-Sheet l Filed Sept. 27, 1951 NOV. 30, 1954 M R, FlELDs 2,695,612

HYPODERMIC SYRINGE Filed Sept. 27, 1951 2 ShQetS-Shet 2 IN V EN TOR.

aCC R fle/d5 BY 75ML-(49 W United States Patent O HYPODERMIC SYRINGE Mack R. Fields, Libertyville, Ill., assignor to Abbott Labl oratories, North Chicago, Ill., a corporation of Illinois Application September 27, 1951, Serial No. 248,623

22 Claims. (Cl. 128--218) This invention relates to hypodermic syringes, and more particularly to disposable hypodermic syringes adapted to serve as medicament containers.

Included among the objects and advantages of the present invention, is an eicient and economical hypodermic syringe, which also serves as the container for dispensable medicaments. The syringe is composed of a minimum numberof parts, simplifying the assembly of the complete device. Furthermore, the functional construction minimizes operational motions required in the dispensation of the medicament. The syringe is also capable of aspiration to ascertain whether or not the cannula thereof is in a vein or blood vessel of the patient.

In the accompanying drawings:

Fig. 1 is an exploded perspective view of a hypodermic syringe according to the invention, showing the parts in assembly position;

Fig. 2 is a cross sectional view of the barrel of the syringe;

Fig. 3 is the top plan view of the barrel of the syringe;

Fig. 4 is a cross section of the barrel along line 4 4 of Fig. 2;

Fig. 5 is a cross sectional elevation of the cap;

Fig. 6 is a partial section of the plunger-piston assembly forthe syringe;

Fig. 7 is a top plan view of the plunger-piston;

Fig. 8 is the side elevation of the thumb-rest of the plunger portion of Fig. 6; and

Fig. 9 is an elevation of the syringe, according to the invention, in operative condition.

The syringe illustrated is composed of three main parts, namely a barrel 10, a sealing cap 26 and a piston-plunger 30. The barrel 10 is a hollow cylindrical tube of a polyethylene plastic having an open end 12 and a partially closed end 11. The open end 12 has a short beveled bore 15 smoothly joined to the main bore. The closed end 11 has an axially aligned dispensing or delivery tube or tip 14 integrally attached thereto. The barrel wall extends beyond the end wall 11, forming an axial ange or lip 22. The exterior surface 21 of the dispensing tip is tapered to the dimensions of a Standard Luer taper, (0.160 in. diameter tip tapering at 326 to the larger end) for attaching a hypodermic cannula thereto. The inner surface 17 of the end 11 is concave inwardly, with a central funnel-shaped opening 19 leading to the dispensing tip 14. The bore of the dispensing tip is slightly enlarged at the outer end 24. Integral linger grips 16 extend laterally near the open end of the syringe. A brace 18 provides rigidity for each of the finger grips 16.

In the embodiment described the various parts of the syringe are made of a polyethylene plastic or other plastic or similar properties. Polyethylene is quite flexible and has a high tensile strength. A syringe so made is practically non-breakable, and consequently is able to withstand considerable abuse. Further, polyethylene is very inert toward most medicaments increasing its adaptability for the purpose contemplated. The plastic is readily molded to correct tolerances, and is easily handled for nal assembly.

A cup-shaped polyethylene cap 26 tightly seals the tip 14 when pushed into place thereon. To insure adequate sealing, a plug 28, integral with the bottom of the cap, snugly tits the ared end 24 of the bore of the tip 14. The entire tip 14 is enclosed in the cap, and an additional seal is formed by the tight fitting juncture betweenthe cap ange 27and the syringe lip 22, when thecap` is fully seated in place. t

The piston-plunger, illustrated in Fig. 6, is a one-piece assembly, embodying the piston 32, the plunger, or piston rod, 30 and the thumb-rest 34. The piston comprises a series of flanges 36 spaced apart, and slightly larger in diameter than the bore of the barrel 1l). The center of symmetry of the flanges extend at an acute angle away from the thumb-rest. The peripheral faces of the flanges are parallel to the plunger axis giving a relatively large bearing surface, to effectuate a secure seal against the barrel wall. Any pressure on the face side of the flanges tends to force them backward against the barrel Wall. The face 33 of the piston has approximately the same curvature as face 17 of the end wall 11 of the barrel insuring complete discharge of medicament from the barrel, when the piston is pushed thereagainst. The plunger 30 has three spaced wells 38 therein, leaving a reinforcing web 37. The three wells cut down the thickness of the material throughout the length of the plunger, and the reinforcing web 37 provides suiiicient rigidity to prevent bending of the plunger under high pressure. The arcuate thumb-rest 34 provides a pressure platform on the end of plunger 30.

In filling the syringe, the three parts i. e. the cap, the barrel and the piston-plunger, are first sterilized, and the piston is inserted into the barrel to a depth which will leave the proper volume in the barrel required for the amount of medicament. The medicament is filled into the barrel through the tip via a needle of smaller diameter than the bore ot' tip 14. After the barrel is filled, the piston is moved inwardly until the medicament completely llls the bore of tip 14, if not already full. The cap 26 is then placed on the tip 14 and pushed so that the plug 28 securely seats in the bore 24. ln this position, flange 27 on the cap seats securely in the notch or annular race between lip or skirt 22 and thebottom of the tip 14. The syringe is thus securely sealed at both ends.`

The known polyethylene plastics of today are opaque materials in th1cK section, but translucent in thin section. lt may be desirable to have a small window 2u, rig. 2, `which is a small area of thin section in the side otthe barrel, so that the contents of tue syringe may be observed.

In operation, the cap 26 is pulled o the tip 14 and discarded. A hypodermic cannula is attached to the tip 14, and the completed assembly is then used in the manner of a standard glass syringe. The cannula is inserted into the body of the patient, the plunger withdrawn slightly to ascertain the position of the needle, and the medicament is dispensed by advancing the piston-plunger.

Others may readily adapt the invention for use under various conditions of service, by employing one or more of the novel features disclosed or equivalents thereof. As at present advised with respect to the apparent scope of my invention, I desire to claim the following subject matter.

I claim:

1. A hypodermic syringe type container, comprising a cylindrical barrel having `an end wall, a restricted axial delivery tube integral with said end wall and communicat` ing with the bore of said barrel, a portion of the wall of said barrel extending axially beyond said end wall forming an annular race between said extending Wall portion and said delivery tube, a reciprocable piston disposed in said barrel, a substantially rigid cap sealing said delivery tube, said cap having means therein adapted to seal the bore of said delivery tube, a flange on said cap adapted to seat in said annular race to completely enclose said delivery tube, said pisten comprising a series of llanges adapted to seal against the Wall of said barrel, and means for attaching a hypodermic cannula to said delivery tube for parenteral administration of the contained medicament.

2. A hypodermic syringe type container, comprising a `cylindrical barrel having an end wall, a restricted axial delivery tube integral with said end Wall and having a bore communicating with the interior of said barrel, a portion of the wall of said barrel extending axially beyond said end wall forming an annular race between said` extending wall portion and said delivery tube, a recipro-` cable piston disposed in said barrel, a cap sealing said delivery tube, an integral plug of less length than the said cap in said cap adapted to seal the bore of said delivery tube, a flange on said cap adapted to seat in said annular race to lcompletely enclose said delivery tube, a charge of medicament retained in usable condition in said barrel by said cap and said piston, and means for attaching a hypodermic cannula to said delivery tube for parenteral administration of the contained medicament.

3. A hypodermic syringe type container, comprising a polyethylene plastic barrel having an end wall, a restricted axial delivery ltube integral with said end wall and communicating with the bore of said barrel, a reciprocable piston disposed in said barrel, a substantially rigid cap .enclosing said delivery tube whereby a charge of medicament is retained in said barrel in usable condition, connecting means in said cap and delivery tube effectively sealing said tube when said cap is placed thereon, said piston comprising a series of spaced flanges adapted to seal against the wall of the bore of said barrel, said barrel having a small area of thin section whereby the contents of the syringe may be observed, and means for connecting a hypodermic cannula to said delivery tube for parenteral administration of the contained medicament.

4. A hypodermic syringe type container, comprising a plastic barrel having `a full .diameter opening at one end thereof, an end wall yclosing the other end .of said barrel, a dispensing tube integral with said end wall and communicating with said barrel, .the wall of said barrel extending .axially .beyond said .end wall forming an annular race between said `extending wall and said tube, the bore of said dispensing .tube having an enlarged diameter portion adjacent the exterior .end thereof, a cup-shaped ,plastic cap enclosing said .dispensing tube, a plug integral with the bottom of said .cap adapted to seat in said enlarged bore portion of .said .dispensing tube .andseal .the bore thereof, a radial fiange adiacent the lip of said cap adapted .to seat in said race and seal against .said .extending barrel Wall; said ,dispensing tube Yadapted to hold a dispensing hypodermic cannula in the absence of said cap, and a plastic piston-plunger reciprocably disposed in said barrel, said piston-plunger comprising an integral piston having a plurality of radially extending sealing anges at one end of a plunger and an integral thumb-rest at the opposite end thereof, said barrel ,adapted as a medicament'carrier when closed by said cap and said piston plunger.

5. A hypodermic syringe type container, comprising a polyethylene plastic barrel having a full diameter opening at one yend thereof, an arcuate end wall closing the other end of said barrel, an axial dispensing tube integral with said end wall Vand communicating with said barrel, the wall of said barrel extending axially beyond said end wall forming an annular race between said extending wall and sa'id tube, the bore of said dispensing tube having an enlarged diameter portion adjacent the exterior end thereof, a pair of manipulative handles diametrically extending outwardly adjacent the open end of said barrel, a substantially rigid .cup-shaped polyethylene plastic cap enclosing said dispensing tube, a plug integral with the bottom of said cap adapted to seat in said enlarged bore portion vof said dispensing tube and seal the bore thereof, a radial flange Vadjacent the lip of said cap adapted to seat in said race and seal against said extending barrel wall; said dispensing tube adapted to hold a dispensing hypodermic cannula in the absence of said cap, and a polyethylene plastic piston-plunger recprocably disposed in said barrel, said'piston-plunger comprising an integral piston having a plurality of radially extending sealing anges at onev end of `a plunger and an integral thumb-rest at .the opposite end thereof, said plunger being a tube strengthened by a reinforcing web structure integral therewith, said piston hav-ing an arcuate face of substantially the same curvature as s aid arcuate end wall, said barrel adapted as a medicament carrier when closed by said cap and said piston-plunger.

6. A hypodermic syringe type container, comprising a polyethylene plastic barrel having a full diameter opening at one 'end thereof, an end wall closing the other end of said barrel, an axial dispensing tube integral with said end wall and communicating with said barrel, the wall of said barrel extending axially beyond said end wall forming ,an annular race between said extending wall and said tube, the bore of said dispensing tube having an enlarged diameter portion adjacent the exterior end thereof, a pair of manipulative handles diametrically extending outwardly adjacent the open end of said barrel, a substantially rigid cup-shaped polyethylene plastic cap enclosing said dispensing tube, a plug integral with the bottom of said cap adapted to seat in said enlarged bore portion of said dispensing tube and seal the bore thereof, a radial flange adjacent the lip of said cap adapted to seat in said race and seal against said extending barrel wall; said dispensing tube adapted to hold a ,dispensing hypodermic cannula in the absence of said cap, and a polyethylene plastic pistonplunger reciprocably disposed in -said barrel, said pistonplunger comprising an integral piston at one end of a plunger and an integral thumb-rest at the opposite end thereof, said plunger being a tube-'like element strengthened by interiorly disposed reinforcing means integral therewith, said barrel adapted as a medicament carrier when closed by said cap and said piston plunger.

7. ln a hypodermic syringe type container including a cylindrical barrel suitable for retaining a medicament -disposed between a reciprocable piston and an end closure cap member, the said barrel having an end wall and a restricted axial delivery tube integral therewith, said delivery tube having an axial bore extending into the said barrel and being tapered for attaching a hypodermic cannula thereto, and the said end wall .extending axially beyond the barrel forming an integra-l skirt about the said delivery tube, the improvement comprising a substantially rigid cap member removably engaging said delivery tube, said cap member having `an integral axial plug of less length than the said cap member for extending into the bore of the delivery tube to seal the said tube, and means on said cap for forming a sealing engagement with the said skirt, whereby the said delivery .tube and the walls of the bore therethrough are rmaintained in a sterile condition when the cap is fully seated.

8. In a hypodermic syringe type container including a cylindrical barrel suitable for retaining a medicament between a reciprocable piston at one end and an end closure cap member at the other end, the said barrel having an end Wall restricting one end of said barrel, a restricted axial delivery tube integral with said end wall, said delivery tube having an axial bore communicating with the interior of the said barrel and being tapered for attaching a hypodermic cannula to the said delivery tube, the said end wall being extended axially forming an integral skirt about the said delivery tube, the improvement comprising a substantially rigid cap member sealing the said delivery tube, said cap member having an integral axial plug of less length than the ,said delivery tube projecting from the end wall of the said cap and extending into the bore of the delivery tube to seal the said tube, a ange on the lower end of said cap suitable for engaging in the annular race formed by the lsaid skirt and delivery tube thereby forming a seal about the said delivery tube, whereby the said delivery tube and walls of the bore therethrough are maintained in a .sterile condition When the cap is fully seated.

9. in a hypodermic syringe type container including .a cylindrical barrel suitable for retaining El medicament ,dis-

posed between a reciprocable piston and ,an end .closure cap member, the improvement. `comprising `a restricted axial delivery tube integral with the said barrel, :said delivery tube having an axial bore therethrough communicating with the said barrel and being tapered .for attaching thereto a hypodermic cannula, .the end wall of .said barrel extending axially beyond the barrel forming an integral skirt about the said delivery tube and an annular race between the said skirt and said delivery tube, a .substantially rigid cap member sealing said `delivery tube, .said cap member having side walls a portion of which aiect, sealing contact with `the walls. of the delivery tube, cap member also having an integral axial plug .of less length than the said cap and .delivery tube -extending into the bore of the delivery tube to seal the said tube, .and a flange on said cap adapted to seat in the said annular race making sealing engagement with the said skirt, whereby the said delivery tube and the walls of the bore therethrough are maintained in a sterile condition.

10. In a sterile container structure including a substantially cylindrical barrel having an end wall and .a restricted delivery tube tapered at one end with an axial;

bore therethrough communicating with the interior of.

the said barrel suitable for receiving the hub of' a hypodermic needle, and the said end-wall being extended axially forming a skirt about the said delivery tube; the improvement comprising a substantially rigid cap member sealing said delivery tube, said cap .member having an integral axial plug ot' less length than the said cap member extending into the bore ot' the delivery tube to seal the said tube when fully seated thereon, and means on the said cap for forming a sealing engagement with the said skirt, whereby said delivery tube and the walls of the bore therethrough are maintained in a sterile condition when the cap member is fully seated thereon.

ll.` ln a sterile container structure including a substantially cylindrical barrel having an end wall and a restricted delivery tube tapered at one end with an axial bore therethrough communicating with the interior of the said barrel suitable for receiving the hub of a hypodermic cannula, the improvement comprising a substantially rigid cap member sealing said delivery tube, said cap member having an integral axial plug of less length than the said cap member extending into the bore of the delivery tube to seal the said tube when fully seated thereon, and means on the said cap for forming a sealing engagement with the outer surface of the said delivery tube and the said cylindrical barrel at a point spaced outwardly from said delivery tube, whereby said delivery tube and walls of the bore therethrough are maintained in a sterile'condition.

12. A hypodermic syringe type container, comprising a cylindrical barrel having an end Wall, an axial delivery tube integral with said end wall and having a bore communicating with the interior of the said barrel, a portion of the said end wall of said barrel extending axially beyond said barrel forming an annular race between said extending wall portion and said delivery tube, a reciprocable piston disposed in said barrel, a cap sealing said delivery tube having an integral plug of less length than the said cap adapted to seal the bore of said delivery tube, a flange on said cap adapted to engage a portion of the said wall forming the said annular race to completely enclose said delivery tube and form a sealing engagement therewith when the cap is fully seated, a charge of medicament retained in usable condition in said barrel by said cap and said piston, and means for attaching a hypodermic cannula to said delivery tube for parenteral administration of the contained medicament.

13. A hypodermic syringe type container, comprising a cylindrical barrel having an end wall, an axial delivery tube integral with said end wall and having a bore com` municating with the interior of the said barrel, a portion of the said end wall of said barrel extending axially beyond said barrel forming an annular race between said extending wall portion and said delivery tube, a reciprocable piston disposed in said barrel, a cap sealing said delivery tube having an integral plug disposed axially thereof which seals the bore of said delivery tube only when the cap is substantially fully seated on the said cylindrical barrel and forms a sealing engagement with the said barrel, a flange on said cap adapted to engage a portion of the said wall forming the said annular race to completely enclose said delivery tube and form a sealing engagement with the said wall when the cap is fully seated, a charge of medicament retained in usable condition in said barrel by said cap and said piston-plunger, and means for attaching a hypodermic cannula to said delivery tube for parenteral administration of the contained medicament.

14. A hypodermic syringe type container, comprising a cylindrical barrel having an end wall, an axial delivery tube integral with said end wall and having a bore communicating with the interior of the said barrel, a portion of the said end wall of said barrel extending axially beyond said barrel forming an annular race between said extending wall portion and said delivery tube, a reciprocable piston disposed in said barrel, a cap sealing said delivery tube having the lower edge thereof adapted to engage a portion of the said wall forming the said annular race to completely enclose said delivery tube and forming a sealing engagement with the said wall when the cap is fully seated, a charge of medicament retained in usable condition in said barrel by said cap and said piston, and means for attaching a hypodermic cannula to said delivery tube for parenteral administration of the contained medicament.

l5. A hypodermic syringe type container, comprising a barrel having a full diameter opening at one end thereof, an end wall closing the other end of said barrel, a dispensing tube integral with said end wall and communicating with said barrel, the `said end wall of said barrel ex'- tending axially beyond said barrel forming an annular race between said extending wall and said tube, a cupshaped cap enclosing said dispensing tube, a plug integral with the bottom of said cap adapted to seat in said dispensing tube and seal the bore thereof, a radial flange adjacent the lip of said cap adapted to seat in said race and seal against said extending end wall; said dispensing tube adapted to hold a dispensing hypodermic cannula in the absence of said cap, and a piston reciprocably disposed in said barrel, said barrel adapted as a medicament carrier when closed by said cap and said piston.

16. A hypodermicjsyringe type container, comprising a barrel having a full diameter opening at one end thereof, an end wall closing the other end of said barrel, an axial dispensing tube integral with said end wall and having the bore thereof communicating with said barrel, the said end wall of said barrel extending axially beyond said barrel forming an annular race between said extending wall and said tube, a pair of manipulative handles diametrically extending outwardly adjacent the open end of said barrel, a substantially rigid cup-shaped cap enclosing said dispensing tube, a plug integral with the bottom of said cap adapted to seat in said bore portion of said dispensing tube and seal the bore thereof, a radial ilange adjacent the lip of said cap adapted to seal against said extending end wall, said dispensing tube adapted to hold a dispensing hypodermic cannula in the absence of said cap, and a piston member reciprocably-disposed in said barrel in sealing engagement with said barrel, said barrel adapted as a medicament carried when closed by said cap and said piston-plunger.

17. ln a hypodermic syringe type container including a cylindrical barrel suitable for retaining ya medicament disposed between a reciprocable piston and an end closure cap member, the improvement comprising an axial delivery tube integral with the end wall of the said barrel, said delivery tube having an axial bore therethrough communicating with the interior of said barrel and being tapered for attaching thereto a hypodermic cannula, the said end wall of said barrel extending axially beyond the barrel forming an integral skirt about the said delivery tube and an annular race between the said skirt and said delivery tube, a substantially rigid cap member sealing said delivery tube, said cap member having an integral axial plug of less length than the said cap and delivery tube extending into the bore of the delivery tube to seal the said tube, and a ange on said cap adapted to making sealing engagement with the said skirt, whereby the said delivery tube and the walls of the bore therethrough are maintained in a steriie condition.

18. In a hypodermic syringe type container including a cylindrical barrel suitable for retaining a medicament disposed between a reciprocable piston and an end closure cap member, the improvement comprising an axial delivery tube integral with the end wall of the said barrel,

said delivery tube having an axial bore therethrough communicating with the interior of said barrel and being tapered at the outer end thereof for attaching thereto a hypodermic cannula, the said end wall of said barrel extending axially beyond the barrel forming an integral skirt about the said delivery tube and an annular race between the said skirt and said delivery tube, a substantially rigid cap member sealing said delivery tube having an integral axial plug which seals the bore of said delivery tube only when the said cap is substantially fully seated on the said cylindrical barrel and forms a sealing engagement with the said barrel, and sealing means on said cap for forming a sealing engagement with the said container at a point spaced longitudinally from the tapered portion of said delivery tube; whereby. the: said tapered portion of the delivery tube and walls of the said bore can be completely exposed to a sterilizing atmosphere while the said cap member is mounted on the said cylindrical barrel and thereafter maintaining the delivery tube and contents of said container in a sterile condition by fully seating the cap on said cylindrical barrel.

19. In a sterile container structure including a substantially cylindrical barrel suitable for retaining a fluid medicinal preparation having an end wall and a restricted delivery tube at one end with an axial bore therethrough communicating with the interior of the said barrel, the said end of the delivery tube being suitable for retaining thereon the hub of a hypodermic needle, the improvement comprising a substantially .rigid cap 2member removably .disposed on the end of the said ldelivery tube, said cap member having yan integral axial .plug of less length vthan the said .cap member .extending -into 4the -bore of the delivery tube to seal the said tube, and `sealing means on said .cap yfor forming .a :sealing engagement wit-h `the said cylindrical barrel at a poi-nt .spaced outw-ardly from the said delivery tube; whereby said delivery tube and walls :of the said bore are maintained in a .sterile condition.

20. In .a sterile Acontainer structure including a substanstantially cylindrical barrel with lateral walls suitable .for retaining a fluid material having an end wall and va restricted delivery .tube `at one end with an laxial bore therethrough .communicating with the interior of the said bar@ rel, .the said `end of the :said delivery tube being suitable for retaining thereon the :hub of a hypodermic needle, the improvement comprising a substantially rigid cap member removably disposed .on the said end of the said del-ivery tube, Asaid cap member :having an integral axial plug which does not form a sealing engagement with the interior of .thesad axial bore while .the cap is mounted on the said cylindrical barrel before being substantially fully seated thereon and which forms a sealing engagement with the interior of .the said axial vbore when the said cap issubstantially fully seated on .the said cylindrical barrel and forms a sealing engagement with the said barrel; and sealing means associated with the said cap for forming a sealing .engagement at a point spaced outwardly from lthe bore of the .said delivery tube; whereby the walls of the said bore .can be completely exposed to a sterilizing atmosphere while the said cap member is mounted on the said cylindrical barrel and thereafter maintaining the delivery tube and contents of said container in a sterile condition by fully .seating the said I22.1. A hypodermic syringe `type container, comprising a Acylindrical barrel having an end wall, a rigid axial delivery tube integral with said end wall and having ya bore communicating with the interior of the said barrel, said delivery tube having at the outer 4end thereof tapered means and a substantially cylindrical portion spaced longitudinally immediately inwardly of the said tapered means, a reciprocable piston disposed in said barrel, a cap member removably mounted on the said delivery tube with an integral axial plug adapted to fit into and form a sealing engagement with the bore of said delivery tube when `the cap is fully seated thereon, said cap member also having a lateral surface adapted to engage the said substantially cylindrical portion of the delivery tube to form a sealing engagement therewith and completely enclosing said tapered means of `the delivery tube when the cap is fully seated thereon to maintain the said tapered portion lfree from external contamination, and a -zchfarge of medicament being .retainable in .usuable sterile condition insaid barrel between said cap .member and said piston.

22. In a hypodermic syringe :type .container including a .cylindrical barrel suitable for retaining Aa .medicament disposed between .a reciprocable .piston .and an end closure cap member, the .improvement `comprising fa Jrestricted .axial delivery tube integral with and extending outwardly from the end wall of the said barrel randhaving an Aaxial bone therethrough communicating with the interior of the said barrel, said delivery tube having at .the outer lend thereof means 4for engaging Va hypoderrnic needle hub .and .having a closure -cap :retaining .surface at the inner .end thereof, the end wall of .said barrel also having a cylindrical portion extending .longitudinally beyond the said `barrel form-ing .an integral skirt ,about the inner end .of .said delivery .tube yand .forming between the .said skirt and said delivery tube an annular race, a removablecap member mounted on .the ysaid delivery tube vand vhaving an integral axial plug projecting from an inner surface thereof adapted 4to extend into the bore of the `delivery tube .and form a sealing engagement with the said axial bore when fully seated on said delivery tube, said cap member also having integral `side walls which are adapted to effect a sealing engagement with the deliver-y tube adjacent the said inner end of .the said delivery tube when fully seated on said delivery `tube to maintain the said means for engaging a hypodennic needle hub free from external contamination, whereby the said means for engaging a hypodermic needle of .the delivery tube and the walls of the said bore of the -delivery tube are maintainable in a sterile condition when the said cap member is fully seated thereon after sterilization treatment.

References Cited in the le of this patent UNITED STATES PATENTS Number Name kDate 803,640 Tagliabue Nov. 7, 1905 1,157,524 Furness Oct. 19, l1915 1,643,531 Wolf Sept. 27, 1927 2,193,489 Nevin Mar. 1'2, 1940 2,512,568 Satlir June 20, 1950 2,551,339 Ryan et al May 1, 1951 2,554,352 Ward et al. May .22, 1951 2,574,964 Eisenstark Nov. 13, 1951 2,575,425 Nelson Nov. 20, 1951 2,602,447 Kollsman July 8, 1952 FOREIGN PATENTS Number Country Date 378,715 Germany July .28, 1923

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