US3743445A - Regulated pump with constant displacement volume - Google Patents

Regulated pump with constant displacement volume Download PDF

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Publication number
US3743445A
US3743445A US00130288A US3743445DA US3743445A US 3743445 A US3743445 A US 3743445A US 00130288 A US00130288 A US 00130288A US 3743445D A US3743445D A US 3743445DA US 3743445 A US3743445 A US 3743445A
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United States
Prior art keywords
control ring
control
ring
housing
rotor
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
US00130288A
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English (en)
Inventor
W Dworak
K Mueller
W Talmon
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.)
Robert Bosch GmbH
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Robert Bosch GmbH
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Filing date
Publication date
Priority claimed from DE19702015744 external-priority patent/DE2015744C3/de
Application filed by Robert Bosch GmbH filed Critical Robert Bosch GmbH
Application granted granted Critical
Publication of US3743445A publication Critical patent/US3743445A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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
    • F04C14/00—Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations
    • F04C14/18—Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations characterised by varying the volume of the working chamber
    • F04C14/22—Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations characterised by varying the volume of the working chamber by changing the eccentricity between cooperating members
    • F04C14/223—Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations characterised by varying the volume of the working chamber by changing the eccentricity between cooperating members using a movable cam

Definitions

  • a pump has a housing with a housing ring, a rotor with pistons, and a control ring between the housing ring and the rotor so that a working space is formed between the rotor and the control ring, and an annular space is formed between the control ring and the housing ring.
  • the annular space is divided into first and second control spaces, connected by throttling means. The first control space receives high pressure fluid, and the second control space discharges into a consumer line.
  • a compensating device responds to the pressure in the consumer line to urge the control ring to increase the working space so that the influence of the fluid pressure and of the piston friction on the control ring is compensated.
  • Another object of the invention is to provide a pump of this type which is of simple construction, inexpensively manufactured, and operates reliably.
  • the present invention arranges a throttle in such a manner that the differential pressure upstream and downstream of the throttle acts directly on the control means which influences thepump volume.
  • the throttle is formed at least partly by the control means, or by gaps between the control means and the housing means. It is also possible to provide the throttle passage in a controlring or in a housing ring.
  • control means In order to obtain a very exact regulation to a constant displacement volume, irrespective of the rotary speed of the rotor, it is advantageous to apply to the control means an additional force which is proportional to the pressure in a consumer line connected to the outlet of the pump, and opposes the torque exerted by the rotor on the control means due to the fluid pressure and friction of the rotor pistons on a control ring.
  • a pump of this type is particularly suited for the power steering of motorcars.
  • Hydraulic power steering apparatus requires that the amount of fluid necessary for steering is already pumped at idling speed, without being substantially increased at the highest rotary speed of the pump.
  • An embodiment of the regulated pump comprises housing means including a housing ring; a rotor mounted in the housing means and including radial piston means; a control ring mounted in the housing ring for movement in first and second direction transverse to the axis of the rotor, and surtrol ring is slidingly engaged by the piston means, and
  • the outer surface of the control ring and the inner surface of the housing ring define first and second control spaces located on opposite sides of a plane passing through the rotor axis transverse to the first and second directions; biassing means mounted in the housing means forbiassing the control-ring to move in the first direction to a first end position abutting the rotor on one side so that a working space is formed on the other side between the rotor and the inner surface of the control ring, the housing means having inlet and outlet ports inthe working space, 'an'd' .a conduitconnecting the outlet port with the first control space; outlet means for a consumer apparatus communicating with the second control space; and throttling means.
  • the throttling means are either formed by the control ring,'or by the housing ring, or by a gap between portions of both rings, and directly connect the first and second control spaces so that at high rotary speeds, the
  • a compensating device is biased by pressure fluid to engage the control ring and to bias the same in the first direction.
  • FIG. 1 is an axial sectional view illustrating a first embodiment of the invention
  • FIG. 2 is a cross-sectional view taken on line II-II in FIG. 1;
  • FIG. 3 is a fragmentary cross-sectional view partially in section, illustrating a modification of the embodiments of FIGS. 1 and 2;
  • FIG. 4- is a cross-sectional view illustrating a second embodiment
  • FIG. 5 is a schematic cross-sectional view illustrating a third embodiment of the invention.
  • FIG. 6 is a schematic cross-sectional view illustrating afourth embodiment of the invention.
  • FIG. 7' is a fragmentary cross-sectional view illustrat ing a fifth embodiment of the invention.
  • a housing includes two covers 11 and 10, and a housing ring 12 between the same.
  • a rotor shaft. 14 is mounted on hearings in covers 10 and 11, and has a rotor 15 located centrally in the housing ring 12.
  • a control ring 16 is located within the housing ring 12, surrounding rotor 15.
  • control ring 16 is mounted on a pivot 17 which is supported by the covers 10 and 11, so that control ring 16 can perform a limited angular movement relative to the rotor 15 and to the housing ring 12.
  • Control ring 16 is slightly narrower in axial direction than housing ring 12, and the diameter of its inner surface 20 is slightly greater than the diameter of the outer surface of rotor 15.
  • Rotor 15 has a series of substantially radial slots 18 in which pistons 19 are mounted for radial'movement.
  • pistons 19 which are advantageously constructed as vanes, slidingly abut the inner circular surface 20 of control ring 16.
  • a spring 23 is provided in the annular space formed between housing ring 12 and control ring 16, and urges control ring 16 to turn about pivot 17 so that control ring 16 moves in one direction to an end position abutting a ,stop22 on the inner surface 21 of housingring 12.
  • the control ring 16 is located directly adjacent one side of rotor 15 so that at the other side of the rotor, a crescent-shaped work space 15a is formed between the inner surface of control ring 16 and the outer surface of rotor 15.
  • housing ring 12 has two'inner projections 24 and 25v forming throttle gaps 27 and 26 with the outer surface 16a of control ring 16.
  • the throttle passages 26 and 27 form between control ring 16 and housing ring 12, first and second control spaces 13a, 13bwhich communicate with each other through the throttling means 24,25,26,27.
  • the first control space 13a, in which stop 22 is located, is disposed on the same side as the working space a, and the second control space 13b is connected with an outlet 31 to a consumer line which may lead to power steering apparatus, not shown.
  • two arcuate ports 28,29 are provided, shown in chain lines in FIG. 2.
  • the port 28, which extends over an angle of about 150, is located on the same side as pivot 17, while the corresponding port 29 is located on the other side of the rotor.
  • the port 29 is connected by conduits 30 and 30 in covers 10 and 11 with the first control space 13a.
  • Conduit 30 is shown in chain lines in FIG. 2.
  • control ring 16 has in the second control space 13b, a recess 33a engaged by a projecting part 33 of a piston 34 mounted in a cylinder bore 35 of housing ring 12.
  • the axis of piston 34 and projection 33 is substantially tangential to a circle having its center in the axis of pivot 17, and passing through the rotor axis. Consequently, pressure of piston means 34,37 on control ring 16 will turn the same efficiently about pivot 17 in the same direction as spring 23.
  • a duct 35' in housing ring 12 connects consumer line 31 and the second control space 13b with cylinder 36 on the free side of the differential piston 34.
  • the cylinder portion 37 on the other side of piston 34 is without pressure.
  • control ring 16 In a position of rest of the pump, spring 23 urges control ring 16 to turn about pivot 44 towards an end position abutting stop 22, in which positionthe eccentricity of the circular control ring 16 in relation to the rotor axis is a maximum. If control ring 16 is turned in the opposite direction against the action of spring 23, the center of control ring 16 may be brought to a position coinciding with the axis of rotor 15.
  • the inlet port 28 receives pressure fluid which is pumped by the pistons 19 sweeping the working space 15a, into the outlet port 29, from where it is displaced through the conduit 30 into the first control space 13a.
  • the fluid flows then through the throttle passages 26 and 27 into the second control space 13b, and from the same through the consumer outlet 31 to consumer apparatus, such as power steering motor.
  • the pistons or vanes 19 of rotor 15 exert on control ring 16 a torque, partly due to friction, so that the same is urged to turn about pivot 17 to a position reducing the working space 15a while compressing spring 23.
  • the influence of this torque is undesirable, since it constitutes a regulation of the output volume not only depending on the rotary speed of rotor 15, but also on the pressure.
  • This torque is compensated by the compensating device including differential piston 34,35 since the force exerted by projection 33 on control ring 16 is proportional to the pressure in the consumer line 31 and in the second control space 13b.
  • the force exerted by projection 37 produces a compensating torque tending to turn control ring 16 in clockwise direction about pivot 17 for increasing again the working space 15a. Due to the position of the compensating device, the regulation of the pump is only speeddepending, and not pressure depending.
  • a differential piston 40 has a piston part 40' of great diameter guided in a cylinder bore provided in a screw 41 which is screwed into a bore in the housing.
  • the smaller piston portion 40" extends tangential to the control ring 16.
  • a separate head 43 is provided which is located in recess 32 of control ring 16, and can be slightly displaced due to the rounded shape of head 43.
  • a spring 44 is arranged which performs the function of the spring 23 shown in FIG.
  • a safety valve 47 which opens into a return duct 48, is connected by a conduit 46 with the pressure chamber 45.
  • safety valve 47 opens, and the pressure in cylinder space 45 drops, together with the pressure in control space 13b. Since the pressureacting on control ring 16 in the first control space 13a is higher, control ring 16 is turned about pivot 17 against the action of spring 44, if necessary to a position in which its center coincides with the rotor axis, so that no fluid is pumped.
  • FIG. 4 The embodiment of FIG. 4 is schematically illustrated, and it will be understood that the omitted parts corresponds to the construction shown in FIGS. 1 and 2.
  • the housing ring 12' has two confronting straight parallel guide faces 50, engaged by corresponding straight opposite guide faces provided on control ring 16.
  • the pivot 17 of FIGS. 1 and 2 is omitted, and the movement of control ring 16 due to the action of spring 23', or due to the fluid pressure in the control space 13a, is rectilinear.
  • a conduit 52 is provided in the housing ring 12, and has a narrow throttle passage 51. Conduit 52 is arranged in housing ring 12 to connect the first control space 13a with the second control space 13b so that a pressure differential is created between the two control spaces on opposite sides of control ring 16'.
  • Adjusting means are provided for varying the free cross section of the throttling passage 51, and include a needle 51 having a threaded head 51a engaging a threaded bore in the housing ring 16' so that the point of the needle can be moved into and out of the throttling passage 51 for adjusting the throttle.
  • the torque exerted by rotor 15 on the control ring 16, which may cause jamming, is balanced by the pressure in balancing chambers 53 provided in the guide faces 50.
  • the pressure differential between the control spaces 13a and 13b, directly acts on the control ring 16', without any intermediate or conduit linkage.
  • the crosssection or throttle passage 51 is adjusted by needle 51', the differential pressure acting on control ring 16' is also adjusted, so that any desired constant displacement volume can be obtained by adjustment of the throttle.
  • FIG. 5 Another embodiment of the invention is schematically illustrated in FIG. 5.
  • the projections 26 and 27 on the inner surface of housing ring 12' cooperate with the outer surface of control ring 16' to form two throttling passages, as described with reference to FIG. 2.
  • control ring 16' has two diametrically projecting piston portions 55 and 56 provided in cylinder bores of housing ring 12'', and spring 23" acts on piston 56 to urge control ring 16" in one direction.
  • the control spaces 13a and 13b operate as described with reference to FIGS. 1 and 2.
  • Two compensating devices 57 and 58 are diametrically arranged and have piston portions 57a and 58a movable in substantially tangential direction of control ring 16", which is engaged by the piston portions 57a and 58a.
  • the compensating devices 57 and 58 are connected with the second control space 131;.
  • the provision of two diametrically arranged compensating devices 57 and 58, instead ofonly one, as: in FIGS. 1 and 2, has the advantage that jamming of the pistons and 56 in the corresponding bore of housing ring 12', is prevented.
  • the pivot 17 is also omitted, and the aligned slots 60 and 61 are provided in the control ring 60".
  • Guide pins 62,63 are secured to the housing, not shown, and project into the slots 60 and 61 so that the control ring 60" is guided for rectilinear movement.
  • Compensating devices as shown in FIG. 5, may be provided, but are not shown.
  • the arrangement of the throttling. gaps 26 and 27 correspond to the construction described with reference to FIG. 2. i
  • the throttling means is provided in the control ring 16".
  • a straight conduit 66 extends along a chord in control ring 16"", and opens into control spaces 13a and 13b.
  • a narrow throttle passage produces a pressure differential between the control spaces 13a and 13b.
  • Sealing means 67 and 68 are located in recesses 69,70 of housing ring 12". The differential pressure between control spaces 13a and 13b urges the sealing means 67 and 68 into fluid-tight engagement with the outer surface of control ring 16"" and the surfaces of recesses 69,70, so that the control spaces are fluid tightly separated from each other.
  • a pivot 17 supports the control ring 16 for angular movement, as described with reference to FIG. 2.
  • Spring 23 urges control ring 16"" into abutment with stop 22 on housing ring 12"".
  • Sealing means 67,68 may be constructed as elastic rolls, or as sealing lips.
  • Regulated pump with constant displacement volurne comprising housing means including a housing ring; a rotor mounted in said housing means for rotation about an axis, and including radial piston means; a control ring mounted in said housing means within said housing ring for movement in first and second opposite directions transverse to said axis, and surrounding said rotor so that the inner surface of said control ring is slidingly engaged by said piston means, and so that the outer surface of said control ring and the inner surface of said housing ring define first and second control spaces located on oppositesides of a plane passing through'said axis transverse to said first and second directions; biasing means mounted in said housing means for biasing said control ring to move in said first direction to a first end position adjacent to said rotor on one side so that a working space is formed on the other side between said rotor and the inner surface of said control ring; said housing means having inlet and outlet ports in said working space, and a conduit connecting said outlet port with said first control space; outlet means for a consumer
  • Regulated pump as claimed in claim 1 comprising a pivot located in said plane and mounted in said housing means eccentric to said axis for supporting said control ring for angular movement between said first and second end positions.
  • throttling means includes adjusting means for varying the throttling flow cross section.
  • Regulated pumr as claimed in claim 6 comprising at least two compensating devices located on opposite sides of another plane passing'through said'axis perpendicularly to said plane; wherein said control ring has two diametrically disposed outward projecting piston portions located in said other plane; wherein said housing ring has two diametrically disposed bores receiving said piston portions for guiding said control ring for straight movement in said first and second directions; and wherein said biassing means is a spring located in one of said bores for urging said control ring to move in said first direction.
  • Regulated pump as claimed in claim 1, comprising a pivot located in said plane and mounted in said housing means eccentric to saidaxis for supporting said control ring for angular movement between said first and second end positions; and wherein said throttling means includes two diametrically disposed throttles located in said plane.
  • Regulated pump as claimed in claim 1, comprising a pivot pin located in said plane supported in said housing; and wherein said control ring has a bearing bore in which said pivot pin is located eccentric to said axis for supporting said control ring for angular movement between said first and second positions.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Details And Applications Of Rotary Liquid Pumps (AREA)
  • Rotary Pumps (AREA)
US00130288A 1970-04-02 1971-04-01 Regulated pump with constant displacement volume Expired - Lifetime US3743445A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19702015744 DE2015744C3 (de) 1970-04-02 Regelbare Rotationskolbenpumpe

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US3743445A true US3743445A (en) 1973-07-03

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ID=5766919

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US00130288A Expired - Lifetime US3743445A (en) 1970-04-02 1971-04-01 Regulated pump with constant displacement volume

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US (1) US3743445A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
BE (1) BE765105A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
CS (1) CS163243B2 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
FR (1) FR2089048A5 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
GB (1) GB1312432A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
RO (1) RO58901A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3865515A (en) * 1973-12-05 1975-02-11 Trw Inc Self adjusting tangency-clearance compressor with liquid purge capability
US4496288A (en) * 1981-12-22 1985-01-29 Toyoda Koki Kabushiki Kaisha Vane type pump with a variable capacity for power steering devices
US4531898A (en) * 1983-12-13 1985-07-30 Nissan Motor Co., Ltd. Control system for a vane type variable displacement pump
US4531893A (en) * 1982-09-28 1985-07-30 Kabushiki Kaisha Fujikoshi Variable output vane pump
US4927332A (en) * 1985-04-17 1990-05-22 Mannesmann Rexroth Gmbh Vane pump
WO2006018272A1 (de) * 2004-08-17 2006-02-23 Daimlerchrysler Ag Einstellvorrichtung, insbesondere für ein kraftfahrzeug
US20080187446A1 (en) * 2007-02-06 2008-08-07 Staley David R Pressure regulating variable displacement vane pump
US20140034779A1 (en) * 2012-08-02 2014-02-06 Bell Helicopter Textron Inc. Independent blade control system with hydraulic cyclic control
US9061760B2 (en) 2012-08-02 2015-06-23 Bell Helicopter Textron Inc. Independent blade control system with rotary blade actuator
US9162760B2 (en) 2012-08-02 2015-10-20 Bell Helicopter Textron Inc. Radial fluid device with multi-harmonic output
US9376205B2 (en) 2012-08-02 2016-06-28 Bell Helicopter Textron Inc. Radial fluid device with variable phase and amplitude

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2635551A (en) * 1948-03-18 1953-04-21 Houdaille Hershey Corp Adjustable variable displacement pump
US2716945A (en) * 1952-10-17 1955-09-06 Bendix Aviat Corp Variable stroke rotary cylinder pump
US2775946A (en) * 1953-03-02 1957-01-01 George H Hufferd Constant delivery variable pressure pump
US3028814A (en) * 1957-10-17 1962-04-10 Houdaille Industries Inc High speed variable displacement pump
US3067693A (en) * 1958-12-24 1962-12-11 United Aircraft Corp Control means for variable delivery pump
US3626810A (en) * 1969-01-21 1971-12-14 Silent Hydropower Inc Variable reversible piston pump

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2635551A (en) * 1948-03-18 1953-04-21 Houdaille Hershey Corp Adjustable variable displacement pump
US2716945A (en) * 1952-10-17 1955-09-06 Bendix Aviat Corp Variable stroke rotary cylinder pump
US2775946A (en) * 1953-03-02 1957-01-01 George H Hufferd Constant delivery variable pressure pump
US3028814A (en) * 1957-10-17 1962-04-10 Houdaille Industries Inc High speed variable displacement pump
US3067693A (en) * 1958-12-24 1962-12-11 United Aircraft Corp Control means for variable delivery pump
US3626810A (en) * 1969-01-21 1971-12-14 Silent Hydropower Inc Variable reversible piston pump

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3865515A (en) * 1973-12-05 1975-02-11 Trw Inc Self adjusting tangency-clearance compressor with liquid purge capability
US4496288A (en) * 1981-12-22 1985-01-29 Toyoda Koki Kabushiki Kaisha Vane type pump with a variable capacity for power steering devices
US4531893A (en) * 1982-09-28 1985-07-30 Kabushiki Kaisha Fujikoshi Variable output vane pump
US4531898A (en) * 1983-12-13 1985-07-30 Nissan Motor Co., Ltd. Control system for a vane type variable displacement pump
US4927332A (en) * 1985-04-17 1990-05-22 Mannesmann Rexroth Gmbh Vane pump
US20070234996A1 (en) * 2004-08-17 2007-10-11 Ansgar-Maria Budde-Gottschalk Adjusting device, in particular for a motor vehicle
WO2006018272A1 (de) * 2004-08-17 2006-02-23 Daimlerchrysler Ag Einstellvorrichtung, insbesondere für ein kraftfahrzeug
US7444978B2 (en) 2004-08-17 2008-11-04 Daimler Ag Adjusting device, in particular for a motor vehicle
US20080187446A1 (en) * 2007-02-06 2008-08-07 Staley David R Pressure regulating variable displacement vane pump
US7862306B2 (en) * 2007-02-06 2011-01-04 Gm Global Technology Operations, Inc. Pressure regulating variable displacement vane pump
US20140034779A1 (en) * 2012-08-02 2014-02-06 Bell Helicopter Textron Inc. Independent blade control system with hydraulic cyclic control
US8973864B2 (en) * 2012-08-02 2015-03-10 Bell Helicopter Textron Inc. Independent blade control system with hydraulic cyclic control
US9061760B2 (en) 2012-08-02 2015-06-23 Bell Helicopter Textron Inc. Independent blade control system with rotary blade actuator
US9162760B2 (en) 2012-08-02 2015-10-20 Bell Helicopter Textron Inc. Radial fluid device with multi-harmonic output
US9376205B2 (en) 2012-08-02 2016-06-28 Bell Helicopter Textron Inc. Radial fluid device with variable phase and amplitude

Also Published As

Publication number Publication date
FR2089048A5 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1972-01-07
GB1312432A (en) 1973-04-04
BE765105A (fr) 1971-08-16
DE2015744A1 (de) 1971-10-21
DE2015744B2 (de) 1976-12-16
RO58901A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1975-11-15
CS163243B2 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1975-08-29

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