US3614266A - Compact positive displacement pump - Google Patents

Compact positive displacement pump Download PDF

Info

Publication number
US3614266A
US3614266A US887950A US3614266DA US3614266A US 3614266 A US3614266 A US 3614266A US 887950 A US887950 A US 887950A US 3614266D A US3614266D A US 3614266DA US 3614266 A US3614266 A US 3614266A
Authority
US
United States
Prior art keywords
pressure
housing
pump
rotor
low
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
US887950A
Other languages
English (en)
Inventor
Fred A Ciampa
Sergio J Mazzola
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.)
Ford Motor Co
Original Assignee
Ford Motor Co
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 Ford Motor Co filed Critical Ford Motor Co
Application granted granted Critical
Publication of US3614266A publication Critical patent/US3614266A/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
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C15/00—Component parts, details or accessories of machines, pumps or pumping installations, not provided for in groups F04C2/00 - F04C14/00
    • F04C15/06—Arrangements for admission or discharge of the working fluid, e.g. constructional features of the inlet or outlet
    • F04C15/062—Arrangements for supercharging the working space
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C14/00—Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations
    • F04C14/24—Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations characterised by using valves controlling pressure or flow rate, e.g. discharge valves or unloading valves
    • F04C14/26—Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations characterised by using valves controlling pressure or flow rate, e.g. discharge valves or unloading valves using bypass channels
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2/00—Rotary-piston machines or pumps
    • F04C2/30—Rotary-piston machines or pumps having the characteristics covered by two or more groups F04C2/02, F04C2/08, F04C2/22, F04C2/24 or having the characteristics covered by one of these groups together with some other type of movement between co-operating members
    • F04C2/34—Rotary-piston machines or pumps having the characteristics covered by two or more groups F04C2/02, F04C2/08, F04C2/22, F04C2/24 or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having the movement defined in groups F04C2/08 or F04C2/22 and relative reciprocation between the co-operating members
    • F04C2/344—Rotary-piston machines or pumps having the characteristics covered by two or more groups F04C2/02, F04C2/08, F04C2/22, F04C2/24 or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having the movement defined in groups F04C2/08 or F04C2/22 and relative reciprocation between the co-operating members with vanes reciprocating with respect to the inner member
    • F04C2/3446—Rotary-piston machines or pumps having the characteristics covered by two or more groups F04C2/02, F04C2/08, F04C2/22, F04C2/24 or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having the movement defined in groups F04C2/08 or F04C2/22 and relative reciprocation between the co-operating members with vanes reciprocating with respect to the inner member the inner and outer member being in contact along more than one line or surface

Definitions

  • Harrington ABSTRACT A positive displacement pump adapted especially for pumping oil in a power steering system for an automotive vehicle, said pump comprising a rotor, slipper elements in the rotor engageable with the cam surface of a relatively stationary pump cam, a pump body surrounding the cam and having internal cavities which define a high-pressure outlet region, the low-pressure fluid inlet region of the pump being defined by other parts of the stationary housing, a reservoir surrounding the pump body and cooperating with a pump pressure plate which is subjected to a. supercharge pressure obtained by the velocity pressure of tfluid bypassed from a fluid control valve situated in the pump body.
  • the improvements of our invention are adapted to be used in fluid pressure pumps for power steering system in automotive vehicles. They include pump components that are arranged in a component fashion to form a pump assembly of reduced dimensions thereby making it possible to package the pump assembly conveniently in a vehicle engine compartment where it may be driven by a belt and pulley arrangement connected to the engine crankshaft. It is possible, however, that other means for driving the rotor of the pump also may be used without departing from the teachings of our invention.
  • the pump assembly of our invention comprises a rotor having peripheral slots in which are positioned pumping slippers which are adapted to contact the cam surface of a surrounding cam member.
  • the cam surface is formed with a generated profile which deviates from the curvature of the periphery of the rotor in a precise, controlled fashion whereby the slippers are caused to reciprocate radially inwardly and outwardly as the rotor is rotated about its axis.
  • the cam member cooperates with the rotor to define a pair of oppositely displaced pumping chambers whereby hydrostatic forces acting on the rotor are substantially balanced thereby reducing or eliminating transverse bearing loads on the rotor due to the development of hydrostatic pressure forces.
  • Each pumping chamber is provided with inlet porting and outlet porting.
  • the outlet porting which is in the high-pressure side of the pump, is formed by means of internal cored passages formed in the pump housing surrounding the cam member.
  • the can member and the rotor are located in the pump housing and are separated from the high-pressure porting by a first and lower pressure plate.
  • the cam, together with the pressure plate, is held in assembled fixed relationship by means of a pin.
  • Internal passages conduct pressure from the high-pressure cavities in the pump housing to a fluid flow control valve assembly situated also in the pump housing as part of the internal pump assembly.
  • the fluid flow control valve establishes a predetermined rate of flow from the pump regardless of the rate at which the rotor is rotated relative to the cam member. Any excess fluid not delivered to the outlet passage of the pump assembly is bypassed through a bypass passage, which in turn communicates with a lowpressure region of the pump surrounding the cam member.
  • the velocity head of the moving fluid in the bypass flow passage is used to supercharge the fluid in the low-pressure region of the circuit.
  • a reservoir surrounding the pump housing is defined in part by an end cover. Fluid is drawn from the reservoir into the low-pressure inlet region of the pump assembly by the aspirating action of the flow in the bypass passage of the flow control valve assembly.
  • the supercharge pressure developed by this aspirating action which is related functionally to the magnitude of the velocity pressure in the bypass flow passage, is distributed to a second or upper pressure plate which engages the so-called pump body, the latter comprises the cam member and the rotor with the reciprocating slippers.
  • the supercharged portion of the low-pressure region is sealed from the main reservoir regions.
  • a bolt or some other suitable fastening device is used to maintain the two pressure plates and the pump body in fixed, assembled relationship with respect to the pump housing.
  • FIG. ll shows a longitudinal cross-sectional view, partly in elevation, of our improved pump assembly. This view is taken along the plane of section line 1l-ll of FIG. 2..
  • FIG. 2 is a cross sectional view of the pump in FIG. I as seen from the plane of section line 2-2 of FIG. 11.
  • FIG. 3 is another cross-sectional view of the pump of FIG. I as seen from the plane of section line 2-3 in FIGS. I, t and 5.
  • FIG. 4 is a cross-sectional view taken along the plane of section line ll-4i of FIG. 3
  • FIG. 5 is a cross sectional view talten along the plane of section line 5-5 of FIG. 3.
  • FIG. 6 is a cross-sectional view taken along the plane of section line 6-6 of FIG. I.
  • FIG. '7 is an assembly view of a rotor, the slippers and the cam member for the assembly of FIG. 1.
  • FIG. 8 is a cross sectional view taken along section line b% of FIG. 7.
  • PARTICULAR DESCRIPTION OF THE INVENTION Numeral It designates a pump housing that may be secured by bracket 12 to the vehicle engine block or to some other suitable structure in the vehicle engine compartment.
  • the embodiment described in this specification is adapted especially to be used in a power steering system for an automotive vehi cle.
  • Housing III has a pump cavity Id which is formed with a flat surface against which lower pressure plate In is positioned.
  • Housing III is formed with a driveshaft opening 118 within which is positioned driveshaft 20.
  • Shaft 20 is journaled by bushing 22 within the opening I8.
  • a shoulder M which is adapted to engage the inner side of the lower pressure plate I6 thereby allowing the thrust forces acting on the shaft 20 to be distributed to the pump housing It] through the pressure plate I6.
  • An upper pressure plate 26 is situated adjacent the end of the shaft 20 as shown at 23.
  • a cam member 30, with circular outside dimensions is situated between the plates I6 and 26.
  • the cavity 114 in the pump housing It is formed with internal threads 32 to accommodate a spanner nut 34 which is threaded into the cavity 141 to retain the pressure plates 26 and I6 and the cam member M) in assembled, stacked relation- Ship.
  • a pump rotor 36 is rotatably positioned within the cam member 30. This is best seen in FIG. 7.
  • Rotor 36 is formed with a splined, central opening 38 in which the end of the shaft 20 is positioned.
  • the shaft end is formed with external splines which drivably engage the internal splines of opening 38.
  • the rotor 36 which is circular, establishes the seal with cam member 30 at the uppermost location ilt) and a lowermost location 42.
  • the internal cam surface of the cam member 30 deviates from the curvature of the rotor at other angular positions to define a pair of opposed worlcing chambers identified in FIG-7 by reference characters M and A6.
  • the contour of the cam surface for the cam member 30 is formed with a shape that contributes to pump efficiency and minimum noise.
  • the cam surface is engaged by the radially outward surfaces of pumping elements in the form of slippers 48.
  • slippers there are eight slippers in the embodiment shown in FIG. 7. Each is received within a slipper pocket 50 in which it may oscillate angularly as well as reciprocate in a radial direction. Each slipper is urged radially outwardly into engagement with the surrounding cam surface by a slipper spring 52, which is seated on the rotor 36. i
  • each slipper rotates in a counterclockwise direction.
  • the leading edge of each slipper is slotted as shown at 55 to permit equalization of pressure in the radially inward region of the slipper pocket and in the working chambers M and d6.
  • These chambers communicate with high-pressure outlet cavity 54 and high-pressure outlet cavity 56. Communication is established with these cavities through porting.
  • a high-pressure port 58 formed in the lower pressure plate 16 is indicated in FIG. 1. It is in communication with each of the high-pressure cavities 56 and 54.
  • the high-pressure cavities 56 and 54 are connected to each other through internal passage structure in the housing 10.
  • Chamber 60 communicates with a corresponding chamber 62 formed l80 out of position as indicated in FIG. 3.
  • Chambers 60 and 62 are joined together by an annular space 64 which surrounds the cam member 30.
  • Annular space 64 is formed by an annular recess fonned in the housing 10. This recess, together with the chambers 60 and 62, forms the low-pressure region of the pump circuit.
  • Cavities 60 and 62 serve as lower pressure inlet ports which communicate with the working chambers 44 and 46.
  • Port 58 serves as one of the outlet ports.
  • Each of the working chambers 44 and 46 has an inlet port and an outlet port.
  • the housing is internally cored to provide a high-pressure port extension 66, which communicates with the valve chamber 68. This communication is established with the valve chamber 68 at the location of annular space 70 indicated in FIGS. 3 and 6.
  • An externally threaded orifice member 72 is received within an internally threaded portion of the chamber 68. It carries an orifice element 74 at its interrnost end. This orifice element is formed with a precalibrated flow control orifice 76 through which fluid discharged into the annular space 70 is allowed to pass. The fluid, which passes through the orifice 76, enters internal pressure delivery passage 78 in the member 72. The pressure in passage 78 is distributed through a flow orifice 80 into internal passage 82, which communicates with spring chamber 84 at one end of the valve chamber 68. A spring 86 located in the spring chamber 84 acts on a movable sleeve 88.
  • Sleeve 88 carries a tapered valve element 90 which is received in the orifice 76.
  • maximum flow area is provided through the orifice 76. If the sleeve 88 is moved against the force of spring 86, the flow area through the orifice 76 is progressively restricted by the tapered valve element 90.
  • Valve element 90 and the cooperating orifice serve as a flow control valve. If the flow to the inner space 70 is increased, the pressure drop across the orifice 76 is increased. This causes the sleeve 88 to move against the force of spring 86, thereby restricting the flow through the orifice 76. The net output flow in the passage 78, which communicates with the pump outlet conduit, is reduced to a value determined by the calibration of the valve element 90'.
  • the outlet flow in pressure passage 78 is determined by the spring 86 because of the action of the orifice 80. If this pressure exceeds a predetermined value, a one-way flow relief valve element 92 becomes unseated thereby establishing a bypass flow path to annular space 94 surrounding the sleeve 88. This space, in turn, communicates with nozzle element 96. The bypass flow is accelerated by the nozzle element 96 and discharged into the annular space 64 surrounding the member 30. This provides a velocity pressure which supercharges the fluid in the annular space 64. Because the static pressure in the path of the accelerated fluid passing through the nozzle 96 is less than ambient pressure, fluid is drawn by the aspirator action thus produced through internal feed passage 98, which communicates with reservoir chamber 100.
  • Reservoir chamber 100 is defined by a reservoir cover 102 which surrounds the housing 10.
  • the cover 102 is sealed by a circular seal 104.
  • the end plate 106 of the cover 102 extends across the cavity 14 outside of the upper pressure plate 26.
  • the upper end of the reservoir communicates with a filler tube 108 which has a suitable inlet to permit filling of the reservoir.
  • a circular gasket seal 110 is positioned between the end wall 106 of the cover 102 and the end of the housing 10 thereby isolating the space between the wall 106 and the pressure plate 26 from the reservoir itself.
  • This space is in fluid communication with the annular space 64 surrounding the member 30.
  • a differential pressure is possible because of the sealing action of the seal 1 10.
  • the supercharge action developed by the velocity pressure in the bypass flow path for the flow control valve helps to avoid cavitation in the pump and it contributes to the overall operating efficiency of the pump It also makes possible a reduced reservoir size.
  • the isolated location of the high-pressure chambers 54 and 56 in the housing 10 eliminates pressure loading in pumps of this type, which is caused by hydrostatic loading of the elements of the pump such as the pressure plates. If the highpressure side of the pump were to be in fluid communication with the pressure plates, a certain amount of deflection would occur and this, in turn, would afiect the pump clearances and tolerances. This in turn would afi'ect adversely the overall operating efficiency of the pump.
  • a positive displacement fluid pump comprising a pump rotor and pumping elements located on the periphery thereof, a pump cam member having a cam surface surrounding said rotor with the pumping elements slidably engaging said cam surface thereby defining pumping chambers, a housing surrounding said cam member, high-pressure passages formed in said housing where they are semi-isolated from said rotor, a first pressure plate located in said housing intermediate one side of said rotor and the adjacent walls of said housing, high pressure outlet ports in said pressure plate establishing communication between said pumping chambers in said earn member and said high-pressure passages in said housing, a second pressure plate adjacent the opposite side of said rotor, inlet ports in one of said pressure plates, a low-pressure inlet chamber formed in part in said housing in fluid communication with said inlet ports, flow control valve means in said housing including a pressure delivery passage and a fluid bypass passage, said valve means being adapted to divide the flow from said outlet ports to said pressure delivery passage and to said bypass passage, the percentage of flow distributed to said bypass
  • a positive displacement fluid pump comprising a pump rotor and pumping elements located on the periphery thereof, a pump cam member having a cam surface surrounding said rotor with the pumping elements slidably engaging said cam surface thereby defining pumping chambers, a housing surrounding said cam member, high-pressure passages formed in said housing where they are semiisolated from said rotor, a first pressure plate located in said housing intermediate one side of said rotor and the adjacent wall of said housing, highpressure outlet ports in said first pressure plate establishing communication between said pumping chambers in said cam member and said high-pressure passages in said housing, a second pressure plate adjacent the opposite side of said rotor, inlet ports in said second pressure plate, a low-pressure inlet chamber formed in part in said housing in fluid communication with said inlet ports, flow control valve means in said housing including a pressure delivery passage and a fluid bypass passage, said valve means being adapted to divide the flow from said outlet ports to said pressure delivery passage and to said bypass passage, the percentage of flow distributed to said bypass passage increasing upon

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Details And Applications Of Rotary Liquid Pumps (AREA)
  • Rotary Pumps (AREA)
  • Reciprocating Pumps (AREA)
US887950A 1969-12-24 1969-12-24 Compact positive displacement pump Expired - Lifetime US3614266A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US88795069A 1969-12-24 1969-12-24

Publications (1)

Publication Number Publication Date
US3614266A true US3614266A (en) 1971-10-19

Family

ID=25392200

Family Applications (1)

Application Number Title Priority Date Filing Date
US887950A Expired - Lifetime US3614266A (en) 1969-12-24 1969-12-24 Compact positive displacement pump

Country Status (6)

Country Link
US (1) US3614266A (de)
JP (1) JPS5125923B1 (de)
CA (1) CA935329A (de)
DE (1) DE2054407C3 (de)
FR (1) FR2074206A5 (de)
GB (1) GB1280447A (de)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3806273A (en) * 1971-10-06 1974-04-23 Trw Inc Pump with means for supercharging the pump inlet
JPS5217904U (de) * 1975-07-25 1977-02-08
DE2915809A1 (de) 1978-05-01 1979-11-08 Ford Werke Ag Verdraengungspumpe, insbesondere fuer servoeinrichtungen in kraftfahrzeugen
US4213744A (en) * 1978-03-03 1980-07-22 Eaton Corporation Hydraulic pump and improved by-pass flow means therefor
EP0026586A1 (de) * 1979-09-27 1981-04-08 General Motors Corporation Durchflussregelventil
US4373871A (en) * 1981-05-04 1983-02-15 General Motors Corporation Compact power steering pump
US4471907A (en) * 1979-06-01 1984-09-18 Amtrol Inc. Venturi pressurizer for incompressible-liquid circulating systems
US4643269A (en) * 1985-10-10 1987-02-17 Ford Motor Company Power steering system for an automotive vehicle having a power steering pump cut out circuit
US5496152A (en) * 1991-11-23 1996-03-05 Luk Farhzeug-Hydraulik Gmbh & Co. Kg Pump with internal valve between suction and pressure regions
WO1997024530A1 (en) * 1995-12-27 1997-07-10 Yeong Hwa Industrial Co., Ltd. Vane pump
WO2007147382A1 (de) * 2006-06-24 2007-12-27 Ixetic Bad Homburg Gmbh Pumpe
US20130094948A1 (en) * 2011-10-13 2013-04-18 Zf Friedrichshafen Ag Intake charged pump for delivering a liquid

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2393956A2 (fr) * 1977-06-07 1979-01-05 Hydro Meca Pompe hydraulique pour l'alimentation d'un dispositif de commande
GB2046953B (en) * 1979-03-22 1983-02-23 Trw Inc Fluid flow control
DE3603148A1 (de) * 1986-02-01 1987-08-13 Rexroth Mannesmann Gmbh Hydropumpe, insbesondere lenkhilfepumpe

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2858766A (en) * 1955-09-19 1958-11-04 Gen Motors Corp Supercharging pump
US2887060A (en) * 1953-06-22 1959-05-19 American Brake Shoe Co Variable volume pumping mechanism
US2983226A (en) * 1953-01-16 1961-05-09 William T Livermore Injection filled liquid pump
CA654271A (en) * 1962-12-18 B. Zeigler Philip Pump

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA654271A (en) * 1962-12-18 B. Zeigler Philip Pump
US2983226A (en) * 1953-01-16 1961-05-09 William T Livermore Injection filled liquid pump
US2887060A (en) * 1953-06-22 1959-05-19 American Brake Shoe Co Variable volume pumping mechanism
US2858766A (en) * 1955-09-19 1958-11-04 Gen Motors Corp Supercharging pump

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3806273A (en) * 1971-10-06 1974-04-23 Trw Inc Pump with means for supercharging the pump inlet
JPS5217904U (de) * 1975-07-25 1977-02-08
JPS5545912Y2 (de) * 1975-07-25 1980-10-28
US4213744A (en) * 1978-03-03 1980-07-22 Eaton Corporation Hydraulic pump and improved by-pass flow means therefor
DE2915809A1 (de) 1978-05-01 1979-11-08 Ford Werke Ag Verdraengungspumpe, insbesondere fuer servoeinrichtungen in kraftfahrzeugen
US4207038A (en) * 1978-05-01 1980-06-10 Ford Motor Company Power steering pump
DE2954135C2 (de) * 1978-05-01 1985-02-07 Ford-Werke AG, 5000 Köln Verdrängerpumpe, insbesondere für Servoeinrichtungen in Kraftfahrzeugen
US4471907A (en) * 1979-06-01 1984-09-18 Amtrol Inc. Venturi pressurizer for incompressible-liquid circulating systems
EP0026586A1 (de) * 1979-09-27 1981-04-08 General Motors Corporation Durchflussregelventil
US4373871A (en) * 1981-05-04 1983-02-15 General Motors Corporation Compact power steering pump
US4643269A (en) * 1985-10-10 1987-02-17 Ford Motor Company Power steering system for an automotive vehicle having a power steering pump cut out circuit
US5496152A (en) * 1991-11-23 1996-03-05 Luk Farhzeug-Hydraulik Gmbh & Co. Kg Pump with internal valve between suction and pressure regions
WO1997024530A1 (en) * 1995-12-27 1997-07-10 Yeong Hwa Industrial Co., Ltd. Vane pump
WO2007147382A1 (de) * 2006-06-24 2007-12-27 Ixetic Bad Homburg Gmbh Pumpe
US20090301586A1 (en) * 2006-06-24 2009-12-10 Ixetic Bad Homburg Gmbh Pump
CN101479483B (zh) * 2006-06-24 2011-04-13 Ixetic巴德霍姆堡有限责任公司 泵
US8235682B2 (en) 2006-06-24 2012-08-07 Ixetic Bad Homburg Gmbh Pump including an insertion valve sleeve having at least one orifice
US20130094948A1 (en) * 2011-10-13 2013-04-18 Zf Friedrichshafen Ag Intake charged pump for delivering a liquid
US9845802B2 (en) * 2011-10-13 2017-12-19 Zf Friedrichshafen Ag Intake charged pump for delivering a liquid

Also Published As

Publication number Publication date
DE2054407A1 (de) 1971-07-01
JPS5125923B1 (de) 1976-08-03
FR2074206A5 (de) 1971-10-01
DE2054407C3 (de) 1981-06-25
DE2054407B2 (de) 1980-11-06
CA935329A (en) 1973-10-16
GB1280447A (en) 1972-07-05

Similar Documents

Publication Publication Date Title
US3614266A (en) Compact positive displacement pump
US5490770A (en) Vane pump having vane pressurizing grooves
US3645647A (en) Positive displacement fluid pumps
US6481990B2 (en) Hydraulically balanced multi-vane hydraulic motor
US5472321A (en) Fuel pump having an impeller with axially balanced forces acting thereon
US2759423A (en) Power transmission
US20100282204A1 (en) Variable displacement vane pump
US4289454A (en) Rotary hydraulic device
US5236315A (en) Hydraulic pump for power-assisted steering system
US5147183A (en) Rotary vane pump having enhanced cold start priming
EP0398377B1 (de) Rotationshydraulikmaschine
US2688924A (en) Piston pump, in particular with eccentric drive
US3164101A (en) Diaphragm pump
ITMI991399A1 (it) Dispositivo di trasporto idraulico a ridotto spazio di montaggio
US6287094B1 (en) Inlet tube diffuser element for a hydraulic pump
EP1211420A2 (de) Flügelzellenpumpe mit veränderlichem Fördervolumen
US4347047A (en) Hydraulic pump for power steering
US2884865A (en) Power transmission
US4298316A (en) Power steering pump
US5549452A (en) Double pump
US5618165A (en) Variable displacement and constant pressure pump
US3787151A (en) Stack-up assembly
US8360746B2 (en) Inverted pressure regulating valve for an engine oil pump
US4495962A (en) Fluid control valve
US3153381A (en) Pump