US3609069A - Peristaltic pump for conveying liquids in chemical apparatus - Google Patents

Peristaltic pump for conveying liquids in chemical apparatus Download PDF

Info

Publication number
US3609069A
US3609069A US877300A US3609069DA US3609069A US 3609069 A US3609069 A US 3609069A US 877300 A US877300 A US 877300A US 3609069D A US3609069D A US 3609069DA US 3609069 A US3609069 A US 3609069A
Authority
US
United States
Prior art keywords
flexible layer
peristaltic pump
plungers
hoses
hose
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US877300A
Inventor
Alfred Martinelli
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Polymetron AG
Original Assignee
Polymetron AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Polymetron AG filed Critical Polymetron AG
Application granted granted Critical
Publication of US3609069A publication Critical patent/US3609069A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B43/00—Machines, pumps, or pumping installations having flexible working members
    • F04B43/0009—Special features
    • F04B43/0054—Special features particularities of the flexible members
    • F04B43/0072—Special features particularities of the flexible members of tubular flexible members
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B43/00—Machines, pumps, or pumping installations having flexible working members
    • F04B43/08—Machines, pumps, or pumping installations having flexible working members having tubular flexible members
    • F04B43/082—Machines, pumps, or pumping installations having flexible working members having tubular flexible members the tubular flexible member being pressed against a wall by a number of elements, each having an alternating movement in a direction perpendicular to the axes of the tubular member and each having its own driving mechanism

Definitions

  • the present invention relates to a peristaltic pump for conveying liquids in chemical apparatus, and more particularly to a peristaltic pump having a flexible layer of material which adapts itself to the level of the surfaces of the individual plungers of the pump.
  • Peristaltic or hose pumps are normally designed in such a manner that one or more of the adjacent hoses containing the liquid to be conveyed are periodically squeezed together by a plurality of mechanically operated plungers arranged one behind the other in the direction of the hoses. As a result of this arrangement, the liquid contained in the hoses is forced along in one direction and sucked through from the other side.
  • the underlying problems are solved in accordance with the present invention by providing a flexible layer of material which adapts itself to the level of the individual plunger surfaces and which is secured under tension between the plungers and the hoses.
  • the arrangement of the present invention assures that the surfaces of the plungers will not press directly upon the hoses. Further, the walls of the hoses follow steadily, rather than jerkily, any changes in the level of the plunger surfaces in cases where the plunger surfaces are arranged at different levels.
  • Another object of present invention is in making readily possible the considerable increase in the surface life of the hoses employed in the peristaltic pump.
  • FIGURE is a sectional elevation view of a peristaltic pump in accordance with the present invention.
  • the camshaft FIGURE illustrates a peristaltic pump, generally designated by the numeral 1, in which a plurality of plungers 10 are periodically raised and lowered through, for example, a camshaft (not shown) so as to squeeze one or more hoses 2 arranged one behind the other in a bed 3 at different points along the length of hoses.
  • a camshaft not shown
  • the contents of the hoses 2 are continuously forced along in a desired unilateral direction.
  • the hoses 2 are mounted in hose couplings 4, 5 to which supply and discharge lines 6, 7 are connected.
  • the plungers l0 and the hoses 2 are separated by a layer of material 8. Orie end of the layer 8 is fixed to the pump housing by conventional securing means 9 and the other end of the layer 8 is resiliently anchored to a spring 20.
  • the layer 8 may be made of polytetrafluorethylene reinforced with glass fiber and having a thickness of from 0.2 mm. to 1.5 mm.
  • ll. 18 possible to lengthen the service life of the hoses 2 from an original service life of 400 hours to a service life of 2,000 hours.
  • the hoses were already defective by the time that 2,000 hours of service life was reached as a result of the squeezing effect of the plungers.
  • a peristaltic pump for conveying liquid including a pump housing, at least one hose for conveying the liquid to be pumped and a plurality of plungers operatively associated with said pump housing and adapted to be selectively moved into squeezing engagement with said at least one hose so as to pump the liquid in a desired unilateral direction, characterized in that a flexible layer of material is arranged between the surfaces of said plungers and said at least one hose, wherein one end of said flexible layer is fixedly connected a tone side of the pump housing and the other end of said flexible layer is resiliently connected at the pump housing, whereby the wall of said at least one hose steadily follows any changes in the level of the surfaces of said plungers.

Abstract

A peristaltic pump for conveying liquids in chemical apparatus having a plurality of plungers. A flexible layer of a material such as polytetrafluorethylene is arranged under tension between the plungers and the hoses containing the liquid to be pumped. The flexible layer of material adapts itself to the level of the surfaces of the individual plungers and, thereby increases the service life of the hoses.

Description

United States Patent Inventor Alli-ed Martinelll Zurich, Switzerland Appl. No. 877,300
Filed Nov. 17, 1969 Patented Sept. 28, 1971 Assignee Polymetron Ltd.
Glattbrugg, Switzerland Priority Mar. 21, 1969 Switzerland 4279/69 PERISTALTIC PUMP FOR CONVEYING LIQUIDS IN CHEMICAL APPARATUS 6 Claims, 1 Drawing Fig.
U.S. Cl 417/474 ..F04b 43/08, 04b 34/12, F04b 45/06 Field of Search 417/474,
[5 6] References Cited UNITED STATES PATENTS 3,083,647 4/1963 Muller 417/474 3,105,447 10/1963 Ruppert 417/475 OTHER REFERENCES Filled Fi'uorocarbons, T. O Rourke, 1964, Modern Plastics, pp. 580- 581 Primary Examiner-Carlton R. Croyle Assistant Examiner-R. E. Gluck Attorney-Craig, Antonelli & l-lill ABSTRACT: A peristaltic pump for conveying liquids in chemical apparatus having a plurality of plungers. A flexible layer of a material such as polytetrafluorethylene is arranged under tension between the plungers and the hoses containing the liquid to be pumped. The flexible layer of material adapts itself to the level of the surfaces of the individual plungers and, thereby increases the service life of the hoses.
PERISTALTIC PUMP FOR CONVEYING LIQUIDS IN CHEMICAL APPARATUS BACKGROUND OF THE INVENTION The present invention relates to a peristaltic pump for conveying liquids in chemical apparatus, and more particularly to a peristaltic pump having a flexible layer of material which adapts itself to the level of the surfaces of the individual plungers of the pump.
Peristaltic or hose pumps are normally designed in such a manner that one or more of the adjacent hoses containing the liquid to be conveyed are periodically squeezed together by a plurality of mechanically operated plungers arranged one behind the other in the direction of the hoses. As a result of this arrangement, the liquid contained in the hoses is forced along in one direction and sucked through from the other side.
In conventional peristaltic pumps, the hoses are subjected to considerable mechanical wear. For this reason, the hoses in these pumps have to be frequently replaced. Despite the use of high-grade hose material, main areas of wear and tear still occur around the edges of the pump plungers.
SUMMARY OF THE INVENTION It is the aim of the present invention to provide a peristaltic pump of the aforementioned type, the hose of which has a considerably increased service life.
The underlying problems are solved in accordance with the present invention by providing a flexible layer of material which adapts itself to the level of the individual plunger surfaces and which is secured under tension between the plungers and the hoses.
The arrangement of the present invention assures that the surfaces of the plungers will not press directly upon the hoses. Further, the walls of the hoses follow steadily, rather than jerkily, any changes in the level of the plunger surfaces in cases where the plunger surfaces are arranged at different levels.
Accordingly, it is an object of the present invention to provide a peristaltic pump which avoids by simple means the shortcomings and disadvantages encountered in the prior art.
Another object of present invention is in making readily possible the considerable increase in the surface life of the hoses employed in the peristaltic pump.
BRIEF DESCRIPTION OF THE DRAWING These and further objects, features and advantages of the present invention will become more apparent from the following description when taken in connection with the accompanying drawing which shows, for purposes of illustration only, an embodiment in accordance with the present invention, and wherein:
The sole FIGURE is a sectional elevation view of a peristaltic pump in accordance with the present invention.
DETAILED DESCRIPTION OF THE DRAWING The camshaft FIGURE illustrates a peristaltic pump, generally designated by the numeral 1, in which a plurality of plungers 10 are periodically raised and lowered through, for example, a camshaft (not shown) so as to squeeze one or more hoses 2 arranged one behind the other in a bed 3 at different points along the length of hoses. By selectively controlling the movement of the plungers 10, the contents of the hoses 2 are continuously forced along in a desired unilateral direction. The hoses 2 are mounted in hose couplings 4, 5 to which supply and discharge lines 6, 7 are connected.
As shown in the sole FIGURE, the plungers l0 and the hoses 2 are separated by a layer of material 8. Orie end of the layer 8 is fixed to the pump housing by conventional securing means 9 and the other end of the layer 8 is resiliently anchored to a spring 20. The layer 8 may be made of polytetrafluorethylene reinforced with glass fiber and having a thickness of from 0.2 mm. to 1.5 mm. By the use of this intermediate layer 8, ll. 18 possible to lengthen the service life of the hoses 2 from an original service life of 400 hours to a service life of 2,000 hours. In the case of conventional peristaltic pump arrangements, the hoses were already defective by the time that 2,000 hours of service life was reached as a result of the squeezing effect of the plungers.
While I have shown and described one embodiment in accordance with the present invention, it is understood that the same is not limited thereto but is susceptible of numerous changes and modifications as known to a person skilled in the art, and I, therefore, do not wish to be limited to the details shown and described herein but intend to cover all such changes and modifications as encompassed by the scope of the invention.
I claim:
1. A peristaltic pump for conveying liquid including a pump housing, at least one hose for conveying the liquid to be pumped and a plurality of plungers operatively associated with said pump housing and adapted to be selectively moved into squeezing engagement with said at least one hose so as to pump the liquid in a desired unilateral direction, characterized in that a flexible layer of material is arranged between the surfaces of said plungers and said at least one hose, wherein one end of said flexible layer is fixedly connected a tone side of the pump housing and the other end of said flexible layer is resiliently connected at the pump housing, whereby the wall of said at least one hose steadily follows any changes in the level of the surfaces of said plungers.
2. A peristaltic pump according to claim 1, wherein said flexible layer consists of polytetrafluorethylene reinforced with glass fiber.
3. A peristaltic pump according to claim 1, wherein said flexible layer has a thickness between about 0.2 and 1.5 mm.
4. A peristaltic pump according to claim 1, wherein said flexible layer consists of poltetrafluorethylene reinforced with glass fiber and has a thickness between about 0.2 to 1.5 mm.
5. A peristaltic pump according to claim 1, wherein said flexible layer is attached at the pump housing under tension.
6. A peristaltic pump according to claim 5, wherein said flexible layer consists of polytetrafluorethylene reinforced with glass fiber and has a thickness between about 0.2 to 1.5

Claims (6)

1. A peristaltic pump for conveying liquid including a pump housing, at least one hose for conveying the liquid to be pumped and a plurality of plungers operatively associated with said pump housing and adapted to be selectively moved into squeezing engagement with said at least one hose so as to pump the liquid in a desired unilateral direction, characterized in that a flexible layer of material is arranged between the surfaces of said plungers and said at least one hose, wherein one end of said flexible layer is fixedly connected a tone side of the pump housing and the other end of said flexible layer is resiliently connected at the pump housing, whereby the wall of said at least one hose steadily follows any changes in the level of the surfaces of said plungers.
2. A peristaltic pump according to claim 1, wherein said flexible layer consists of polytetrafluorethylene reinforced with glass fiber.
3. A peristaltic pump according to claim 1, wherein said flexible layer has a thickness between about 0.2 and 1.5 mm.
4. A peristaltic pump according to claim 1, wherein said flexible layer consists of polytetrafluorethylene reinforced with glass fiber and has a thickness between about 0.2 to 1.5 mm.
5. A peristaltic pump according to claim 1, wherein said flexible layer is attached at the pump housing under tension.
6. A peristaltic pump according to claim 5, wherein said flexible layer consists of polytetrafluorethylene reinforced with glass fiber and has a thickness between about 0.2 to 1.5 mm.
US877300A 1969-03-21 1969-11-17 Peristaltic pump for conveying liquids in chemical apparatus Expired - Lifetime US3609069A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CH427969A CH505294A (en) 1969-03-21 1969-03-21 Peristaltic pump

Publications (1)

Publication Number Publication Date
US3609069A true US3609069A (en) 1971-09-28

Family

ID=4273141

Family Applications (1)

Application Number Title Priority Date Filing Date
US877300A Expired - Lifetime US3609069A (en) 1969-03-21 1969-11-17 Peristaltic pump for conveying liquids in chemical apparatus

Country Status (5)

Country Link
US (1) US3609069A (en)
CH (1) CH505294A (en)
DE (1) DE1944102A1 (en)
FR (1) FR2033730A5 (en)
GB (1) GB1228093A (en)

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4288205A (en) * 1980-01-18 1981-09-08 Pako Corporation Variable volume peristaltic pump
WO1984000691A1 (en) * 1982-08-12 1984-03-01 American Hospital Supply Corp Linear peristaltic pumping apparatus and disposable casette therefor
WO1984000690A1 (en) * 1982-08-12 1984-03-01 American Hospital Supply Corp Peristaltic fluid-pumping apparatus
US4867744A (en) * 1987-05-21 1989-09-19 Baxter International Inc. Peristaltic linear pump with contoured rollers
US4967940A (en) * 1989-02-21 1990-11-06 Minnesota Mining And Manufacturing Co. Method and apparatus for precision squeeze tube valving, pumping and dispensing of work fluid(s)
US5033656A (en) * 1989-02-21 1991-07-23 Minnesota Mining And Manufacturing Company Method and apparatus for precision squeeze tube valving, pumping and dispensing of work fluid (s)
US5035350A (en) * 1989-02-21 1991-07-30 Minnesota Mining And Manufacturing Company Method and apparatus for precision squeeze tube valving, pumping and dispensing of work fluid(s)
US5039279A (en) * 1990-03-15 1991-08-13 Abbott Laboratories Sensor for detecting fluid flow from a positive displacement pump
US5055001A (en) * 1990-03-15 1991-10-08 Abbott Laboratories Volumetric pump with spring-biased cracking valves
US5078362A (en) * 1990-03-15 1992-01-07 Abbott Laboratories Spring-biased valve for use in a positive displacement volumetic pump
US5116203A (en) * 1990-03-15 1992-05-26 Abbott Laboratories Detecting occlusion of proximal or distal lines of an IV pump
US5158437A (en) * 1990-03-15 1992-10-27 Abbott Laboratories Volumetric pump with spring-biased cracking valves
US5180287A (en) * 1990-03-15 1993-01-19 Abbott Laboratories Method for monitoring fluid flow from a volumetric pump
US5357827A (en) * 1990-03-15 1994-10-25 Abbott Laboratories Torque compensated cam assembly and method
US5660529A (en) * 1994-12-06 1997-08-26 Mcgaw, Inc. Linear peristaltic pump with reshaping fingers interdigitated with pumping elements
US6234773B1 (en) 1994-12-06 2001-05-22 B-Braun Medical, Inc. Linear peristaltic pump with reshaping fingers interdigitated with pumping elements
US20020006668A1 (en) * 2000-07-11 2002-01-17 Katsuaki Takahashi Dispensing apparatus
US20120063923A1 (en) * 2010-09-10 2012-03-15 Ly Jeff Positive grip fingers in a peristaltic pump
US20180339102A1 (en) * 2015-11-20 2018-11-29 Advanced Microfluidics Sa Micropump
US11241530B1 (en) 2020-11-23 2022-02-08 Amf Medical Sa Insulin patch pump having photoplethysmography module
US11529464B1 (en) 2021-06-01 2022-12-20 Amf Medical Sa Systems and methods for monitoring delivery of microdoses of medication
US11529458B2 (en) 2017-12-08 2022-12-20 Amf Medical Sa Drug delivery device
US11679199B2 (en) 2021-06-01 2023-06-20 Amf Medical Sa Systems and methods for delivering microdoses of medication
US11857757B2 (en) 2021-06-01 2024-01-02 Tandem Diabetes Care Switzerland Sàrl Systems and methods for delivering microdoses of medication

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE788703A (en) * 1971-09-16 1973-01-02 Rohe Scientific Corp PERISTALTIC PUMP
JPS5421603A (en) * 1977-07-19 1979-02-19 Pilot Pen Co Ltd Method of extracting even quantity of liquid by trickling
US4212598A (en) * 1978-07-20 1980-07-15 Energy Development Corporation Traffic-operated air-powered generating system
US4500266A (en) * 1981-09-24 1985-02-19 Amf Incorporated Linear peristaltic pump
GB2128262A (en) * 1982-09-15 1984-04-26 Thomas John Mcneel Robertson Peristaltic pump or motor
DE102012012229A1 (en) * 2012-06-19 2013-12-19 Thomas Magnete Gmbh Dosing pump for conveying and dosing viscous fluids, has hose for enclosing dosing fluid, where hose is pressed against bearing by flexible devices so that fluid cannot flow back and forth of in zone of hose

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3083647A (en) * 1961-05-08 1963-04-02 John T Muller Metering device
US3105447A (en) * 1961-08-28 1963-10-01 Ruppert Robert Gene Pump construction

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3083647A (en) * 1961-05-08 1963-04-02 John T Muller Metering device
US3105447A (en) * 1961-08-28 1963-10-01 Ruppert Robert Gene Pump construction

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Filled Fluorocarbons, T. O Rourke, 1964, Modern Plastics, pp. 580 581 *

Cited By (35)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4288205A (en) * 1980-01-18 1981-09-08 Pako Corporation Variable volume peristaltic pump
WO1984000691A1 (en) * 1982-08-12 1984-03-01 American Hospital Supply Corp Linear peristaltic pumping apparatus and disposable casette therefor
WO1984000690A1 (en) * 1982-08-12 1984-03-01 American Hospital Supply Corp Peristaltic fluid-pumping apparatus
US4482347A (en) * 1982-08-12 1984-11-13 American Hospital Supply Corporation Peristaltic fluid-pumping apparatus
US4493706A (en) * 1982-08-12 1985-01-15 American Hospital Supply Corporation Linear peristaltic pumping apparatus and disposable casette therefor
US4867744A (en) * 1987-05-21 1989-09-19 Baxter International Inc. Peristaltic linear pump with contoured rollers
US4967940A (en) * 1989-02-21 1990-11-06 Minnesota Mining And Manufacturing Co. Method and apparatus for precision squeeze tube valving, pumping and dispensing of work fluid(s)
US5033656A (en) * 1989-02-21 1991-07-23 Minnesota Mining And Manufacturing Company Method and apparatus for precision squeeze tube valving, pumping and dispensing of work fluid (s)
US5035350A (en) * 1989-02-21 1991-07-30 Minnesota Mining And Manufacturing Company Method and apparatus for precision squeeze tube valving, pumping and dispensing of work fluid(s)
US5039279A (en) * 1990-03-15 1991-08-13 Abbott Laboratories Sensor for detecting fluid flow from a positive displacement pump
US5055001A (en) * 1990-03-15 1991-10-08 Abbott Laboratories Volumetric pump with spring-biased cracking valves
US5078362A (en) * 1990-03-15 1992-01-07 Abbott Laboratories Spring-biased valve for use in a positive displacement volumetic pump
US5116203A (en) * 1990-03-15 1992-05-26 Abbott Laboratories Detecting occlusion of proximal or distal lines of an IV pump
US5158437A (en) * 1990-03-15 1992-10-27 Abbott Laboratories Volumetric pump with spring-biased cracking valves
US5180287A (en) * 1990-03-15 1993-01-19 Abbott Laboratories Method for monitoring fluid flow from a volumetric pump
US5357827A (en) * 1990-03-15 1994-10-25 Abbott Laboratories Torque compensated cam assembly and method
US5660529A (en) * 1994-12-06 1997-08-26 Mcgaw, Inc. Linear peristaltic pump with reshaping fingers interdigitated with pumping elements
US6234773B1 (en) 1994-12-06 2001-05-22 B-Braun Medical, Inc. Linear peristaltic pump with reshaping fingers interdigitated with pumping elements
US5888052A (en) * 1994-12-06 1999-03-30 Mcgraw, Inc. Linear peristaltic pump with reshaping fingers intedigitated with pumping elements
US20020006668A1 (en) * 2000-07-11 2002-01-17 Katsuaki Takahashi Dispensing apparatus
US6740529B2 (en) * 2000-07-11 2004-05-25 Hitachi, Ltd. Dispensing apparatus
US20120063923A1 (en) * 2010-09-10 2012-03-15 Ly Jeff Positive grip fingers in a peristaltic pump
US20180339102A1 (en) * 2015-11-20 2018-11-29 Advanced Microfluidics Sa Micropump
US11806502B2 (en) * 2015-11-20 2023-11-07 Tandem Diabetes Care Switzerland Sarl Micropump
US11529458B2 (en) 2017-12-08 2022-12-20 Amf Medical Sa Drug delivery device
US11813428B2 (en) 2017-12-08 2023-11-14 Tandem Diabetes Care Switzerland Sárl Patch pump device for drug delivery
US11241530B1 (en) 2020-11-23 2022-02-08 Amf Medical Sa Insulin patch pump having photoplethysmography module
US11529460B1 (en) 2021-06-01 2022-12-20 Amf Medical Sa Systems and methods for delivering microdoses of medication
US11541169B2 (en) 2021-06-01 2023-01-03 Amf Medical Sa Applicators for systems and methods for delivering microdoses of medication
US11679199B2 (en) 2021-06-01 2023-06-20 Amf Medical Sa Systems and methods for delivering microdoses of medication
US11712514B2 (en) 2021-06-01 2023-08-01 Tandem Diabetes Care Switzerland Sàrl Cannulas for systems and methods for delivering microdoses of medication
US11529461B1 (en) 2021-06-01 2022-12-20 Amf Medical Sa Initialization for systems and methods for delivering microdoses of medication
US11813382B2 (en) 2021-06-01 2023-11-14 Tandem Diabetes Care Switzerland Sàrl Cannulas for systems and methods for delivering microdoses of medication
US11529464B1 (en) 2021-06-01 2022-12-20 Amf Medical Sa Systems and methods for monitoring delivery of microdoses of medication
US11857757B2 (en) 2021-06-01 2024-01-02 Tandem Diabetes Care Switzerland Sàrl Systems and methods for delivering microdoses of medication

Also Published As

Publication number Publication date
CH505294A (en) 1971-03-31
FR2033730A5 (en) 1970-12-04
DE1944102A1 (en) 1970-10-01
GB1228093A (en) 1971-04-15

Similar Documents

Publication Publication Date Title
US3609069A (en) Peristaltic pump for conveying liquids in chemical apparatus
US4818191A (en) Double-acting diaphragm pump system
US2303597A (en) Measuring pump
US3680985A (en) Pump
SE8900164D0 (en) DISPENSES FOR PRODUCTS IN SUCH FORM
US2671412A (en) Collapsible chamber pump with rotary compress
US2595737A (en) Jet pump
GB1347642A (en) Apparatus for pumping semiliquid material
GB1269545A (en) Improvements relating to devices for dispensing pastes or liquids
GB1437335A (en) Pump
GB1085511A (en) Hydraulic reciprocating pumps
US4386782A (en) Guide and seal assembly for a piston of a drowned piston type pump
US3920356A (en) Reciprocating pump
US2918878A (en) Double-acting diaphragm pump
US3204568A (en) Diaphragms
US2192325A (en) Pump for chemical materials
US3632236A (en) Cam operated fluid pumps
GB1258956A (en)
ES346871A1 (en) Improvements in Flexible Chamber Pumps
GB1534650A (en) Pulsation-free feeding pump
GB1506669A (en) Positive displacement metering pump
GB923443A (en) Flexible tube pump
US2546302A (en) Flexible diaphragm pump
GB1264019A (en) Oscillating piston pump
SU954606A1 (en) Positive-displacement pump