US3918855A - Adjustable vane pump - Google Patents

Adjustable vane pump Download PDF

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Publication number
US3918855A
US3918855A US493969A US49396974A US3918855A US 3918855 A US3918855 A US 3918855A US 493969 A US493969 A US 493969A US 49396974 A US49396974 A US 49396974A US 3918855 A US3918855 A US 3918855A
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US
United States
Prior art keywords
rotor
slide block
housing
radially
abutment
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
US493969A
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English (en)
Inventor
Siegfried Bornholdt
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Bosch Rexroth AG
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GL Rexroth GmbH
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Application filed by GL Rexroth GmbH filed Critical GL Rexroth GmbH
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Publication of US3918855A publication Critical patent/US3918855A/en
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    • 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

  • the present invention relates to hydraulic machines in general, and more particularly to improvements in hydraulic pumps or motors with radially or substantially radially movable liquid displacing elements, such as pistons or vanes. Still more particularly, the invention relates to improvements in hydraulic machines wherein the strokes of radially movable liquid displacing elements are variable to thereby change the amounts of displaced liquid.
  • the invention will be described with reference to vane pumps but with the understanding that it can also be embodied in radial piston machines.
  • the adjustments mechanism for the slide block includes a pair of coaxial plungers which are movable radially of the rotor and engage the external surface of the slide block so that the latter can be moved radially of the rotor to change the distance between its axis and the rotor axis.
  • the adjustment mechanism further normally comprises a plate-like stop which engages the external surface of the slide block at the higher-pressure side of the rotor and is held at a given distance from the rotor axis by an abutment which is fixedly mounted in the housing.
  • a roller bearing is interposed between the abutment and the plate-like stop.
  • An object of the invention is to provide a novel and improved adjustment mechanism for the annular slide block of a hydraulic machine, especially a vane pump.
  • Another object of the invention is to provide an adjustment mechanism which allows for displacement of the slide block in order to change the noise level of the machine as well as for hysteresisand vibration-free shifting of the slide block for the purpose of changing the throughput of the machine.
  • a further object of the invention is to provide a vane pump which embodies the improved adjustment mechanism and wherein the adjustment mechanism occupies a negligible amount of space and consists of a relatively small number of simple, compact and long-lasting components.
  • An additional object of the invention is to provide an adjustment mechanism for the slide block of a vane pump or the like wherein the means for changing the noise level undergoes a minimum of wear and insures that the slide block can be displaced with respect to the rotor without any or with minimal slippage relative to those parts of the adjustment mechanism which directly engage the external surface of the slide block.
  • the invention is embodied in a hydraulic machine, particularly in a vane pump, which comprises a housing for a rotor, an annular slide block which spacedly surrounds the rotor in the housing, liquid displacing elements mounted in the rotor for movement substantially radially of the rotor axis and abutting against the internal surface of the slide block, at least while the rotor is driven, and an adjustment mechanism for the slide block.
  • the adjustment mechanism includes at least one plunger or an analogous adjusting member which abuts against the external surface of the slide block and is movable in the housing substantially radially of the rotor in a predetermined direction to thereby change the distance between the axes of the slide block and rotor and hence the amount of liquid which is displaced by the liquid displacing elements, an arresting member which is angularly offset from the adjusting member by less than 180 (preferably by as considered in the circumferential direction of the rotor and has a flat or convex contact surface abutting against the external surface of the slide block at the higher-pressure side of the rotor, an adjustable abutment located in the housing radially outwardly of the arresting member, and a spherical insert interposed between the arresting member and abutment and preferably extending with minimal clearance into a socket provided therefor in a second surface of the arresting member opposite the contact surface.
  • the abutment is preferably formed with a concave surface which is
  • the radius of curvature of the contact surface as considered in the direction of movement of the slide block under the action of the adjusting member or members, exceeds the distance from the locus of contact between the insert and abutment to the locus of contact between the arresting member and slide block. This insures that the throughput of the machine can be changed without hysteresis and/or vibration because, when the slide block is shifted radially of the rotor by the adjusting member or members, the external surface of the slide block rolls along the contact surface and such external 3 surface does not slide with respect to the adjusting member or members.
  • the abutment is preferably rigid with or forms part of a screw which meshes with and is rotatable relative to the housing to move the abutment radially of the rotor.
  • This screw is preferably provided with a recess for the abutment and insert as well as for the major portion of the arresting member. Radial adjustments of the abutment through the medium of the screw are effected to change the noise level of the machine.
  • FIG. 1 of the drawing is a transverse sectional view of a vane pump which embodies the improved adjustment mechanism for the slide block, and
  • FIG. 2 illustrates a modification of an element shown in FIG. 1.
  • FIG. 1 shows a vane pump having a housing 1 for a rotor 2 which is secured to or made integral with a drive shaft 3.
  • the periphery of the rotor 2 has radially extending slots 4 for liquid displacing vanes 5 having outer end portions 5a which abut against the endless internal surface 6a of an annular slide block 6.
  • the shaft 3 is driven by a motor (not shown) and the pump is to convey fluid from the inlet means to the outlet means of the housing 1, the axis of the slide block 6 is parallel to but spaced apart from the common axis A of the rotor 2 and drive shaft 3.
  • the direction in which the shaft 3 rotates is indicated by an arrow 14.
  • inlet means, outlet means and the customary valve plate in the housing 1 may be similar to or identical with that disclosed in the commonly owned copending application Ser. No. 463,781 of Bornholdt et al. filed Apr. 24, 1974 for Hydraulic Machine With Air Vent Valve".
  • the adjustment mechanism for changing the eccentricity of the slide block 6 includes parts which engage the endless external surface 6b of the slide block.
  • Such parts include two hydraulically operated adjusting plungers 7 and 8 which are located diametrically opposite each other with respect to the axis A. These plungers are respectively reciprocable in radially extending cylinders 7a, 8b of the housing 1 and the outermost position of the plunger 7 (at a maximum distance from the axis A) is determined by an adjustable stop 9 having external threads in mesh with the internal threads of a cover 12 forming part of or secured to the housing 1.
  • the stop 9 can be fixed in a selected axial position by a lock nut 11.
  • a sealing ring in a circumferential groove of the stop 9 prevents leakage of fluid from the cylinder 7a toward the lock nut 11, and a gasket 13 prevents leakage of fluid between the cover 12 and the main body portion of the housing 1.
  • the means for shifting the slide block 6 (in directions indicated by a double-headed arrow 22) by admitting pressurized fluid into the chamber 7a or 8b forms no part of the invention; such means may include a manually actuatable or automatic follow-up control system serving to change the eccentricity of the slide block 6 with respect to the rotor 2 and hence the amount of fluid which is conveyed by vanes 5 from the inlet means to the outlet means of the housing 1.
  • the vanes 5 define with the slide block 6 chambers or cells 15 whose volume increases during travel of vanes from the adjusting plunger 8 toward the adjusting plunger 7 (the chambers 15 then draw fluid from the inlet means) and whose volume decreases during travel of vanes 5 from the plunger 7 toward the plunger 8 (the chambers 15 then discharge pressurized fluid through the outlet means which is connected with one or more consumers, not shown).
  • the crescent-shaped space between the internal surface 6a of the slide block 6 and the periphery of the rotor 2 is shown at 16.
  • That surface 17a of the arresting member 17 (hereinafter called plug for short) which faces away from the external surface 612 of the slide block 6 has a socket or recess 17b bounded in part by a cylindrical surface and in part by a conical surface and receiving with relatively small clearance the major portion of a spherical insert 18.
  • the insert 18 abuts against the conical surface 17c and its exposed portion abuts against a concave surface 19a at the inner side of a pressure transmitting abutment member 19.
  • the latter resembles a post which is secured to (e.g., partly recessed into) an adjusting screw 20.
  • the screw 20 has threads 20b meshing with a portion of the housing 1 and has an axially extending recess 20a receiving the major portion of the plug 17 so that the parts 17, 18, 19, 20 occupy a minimum amount of space.
  • the outwardly extending shank of the screw 20 carries a lock nut 21 which prevents accidental axial displacement of the plug 17.
  • a cap 21a conceals the lock nut 21 and can be held in the illustrated position owing to frictional engagement with the facets of the nut 21 or by being separably connected to the housing 1.
  • the radius of curvature of the concave surface 19a exceeds somewhat the radius of the spherical insert 18. This insures that the insert 18 produces a restoring moment in a direction toward the illustrated end position of the slide block 6 and plug 17.
  • the inner or contact surface 17d of the plug 17 abuts against the external surface 61) and has a radius of curvature R (as considered in the direction of arrow 22) which is greater than the distance from the locus (line) 23 of contact between the surfaces 6b, 17d to the locus (point) 24 of contact between the spherical insert 18 and the concave surface 190.
  • the slide block 6 If the slide block 6 is moved by one of the adjusting plungers 7, 8 (to the left or to the right, as viewed in the drawing), the external surface 6b rolls along the contact surface 17d whereby the plug 17 causes the sperical insert 18 to roll along the concave surface 190.
  • the contact surface 17d is flat as shown in FIG. 2, its radius of curvature is infinitely large. If the surface 17d is curved, as considered in the direction of arrow 22, the radius of curvature R is still greater than the distance between the loci 23, 24.
  • the screw 20 is adjusted (upon loosening of the lock nut 21) in order to move the abutment member 19 radially of the rotor 2 and to thus change the level of noise which is produced by the pump.
  • the slide block 6 is shifted by the adjusting plunger 7 or 8 (arrow 22) and its external surface 6b rolls along the contact surface 17d, the inclination of the axis of the plug 17 changes, i.e., the plug 17 can swivel about the locus 24 of contact between the periphery of the spherical insert 18 and the concave surface 19a.
  • the aforedescribed selection of the radius R and the distance between the loci 23, 24 insures that the axis of the slide block 6 moves in the general direction of the arrow 22 when the adjusting plunger 7 or 8 is moved axially to change the throughput of the pump. This, in turn, insures that the surface 6b does not slide with respect to the end face 7b or 8a when the cylinder 7a or 8b receives pressurized fluid to change the extent of radial movement of the vanes 5.
  • the abutment member 19 may constitute an integral part of the screw 20.
  • the housing 1 can be provided with a scale and the screw 20 can carry a pointer to facilitate the positioning of plug 17 at a selected distance from the axis A of the rotor 2. If the operator wishes to change the position of the slide block 6 through the medium of the plug 17, the lock nut 21 is loosened and the screw 20 is rotated. The fluid in the upper chambers of the space 16, as viewed in the drawing, urges the surface 6b against the contact surface 17d so that the axial position of the screw is always indicative of the setting of slide block 6.
  • a combination comprising a housing; a rotor mounted in said housing; an annular slide block located in said housing and spacedly surrounding said rotor, said slide block having endless internal and external surfaces; liquid displacing elements mounted in said rotor for movement substantially radially of the rotor axis and abutting against said internal surface, at least while said rotor is driven; and an adjustment mechanism for said slide block, including at least one adjusting member abutting against said external surface and movable in said housing in a predetermined direction substantially radially of said rotor to thereby change the distance between the axes of said slide block and said rotor, an arresting member angularly offset from said adjusting member by less than 180, as considered in the circumferential direction of said rotor, and having a contact surface abutting against said external surface, said contact surface being flat or convex, as considered in said predetermined direction, an adjustable abutment member located in said housing radi
  • said displacing elements are vanes defining with said slide block a plurality of variable-volume liquid-containing chambers including a first group of chambers wherein the fluid pressure is lower and a second group of chambers wherein the fluid pressure is higher, said arresting member being located radially outwardly of said second group of chambers.
  • said arresting member has a second surface located opposite said contact surface and having a socket receiving a portion of said insert with minimal clearance.
  • said means for moving said abutment member comprises an externally threaded member meshing with said housing and being rotatable to thereby effect a movement of said abutment member radially of said rotor.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Rotary Pumps (AREA)
  • Details And Applications Of Rotary Liquid Pumps (AREA)
US493969A 1973-11-16 1974-08-01 Adjustable vane pump Expired - Lifetime US3918855A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE2357182A DE2357182C2 (de) 1973-11-16 1973-11-16 Verstellbare Flügelzellenpumpe

Publications (1)

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US3918855A true US3918855A (en) 1975-11-11

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Application Number Title Priority Date Filing Date
US493969A Expired - Lifetime US3918855A (en) 1973-11-16 1974-08-01 Adjustable vane pump

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US (1) US3918855A (enrdf_load_stackoverflow)
JP (2) JPS5080509A (enrdf_load_stackoverflow)
DE (1) DE2357182C2 (enrdf_load_stackoverflow)

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4222718A (en) * 1978-03-09 1980-09-16 Rexnord Inc. Linear motion thrust block for hydraulic pumps and motors
US4340338A (en) * 1978-03-09 1982-07-20 Rexnord Inc. Hydraulic pressure biased linear motion thrust block for hydraulic pumps and motors
US4566870A (en) * 1982-11-02 1986-01-28 Itt Industries, Inc. Adjustable vane-type pump
US4715180A (en) * 1984-01-13 1987-12-29 Dynamic Hydraulic Systems, Inc. Hydraulic lift mechanism
US4770616A (en) * 1982-11-20 1988-09-13 Itt Industries, Inc. Variable vane-type pump
US4851723A (en) * 1988-08-01 1989-07-25 Westinghouse Electric Corp. Coolant pump system for variable speed generators
US5033265A (en) * 1989-03-08 1991-07-23 Sundstrand Corporation Coaxial hydraulic actuator system
US5236319A (en) * 1991-05-15 1993-08-17 Mannesmann Rexroth Gmbh Vane pump
US20020114708A1 (en) * 2000-12-12 2002-08-22 Hunter Douglas G. Variable displacement vane pump with variable target regulator
US6457946B2 (en) * 1999-12-23 2002-10-01 Daimlerchrysler Ag Regulatable pump
US20030231965A1 (en) * 2002-04-03 2003-12-18 Douglas Hunter Variable displacement pump and control therefor
US20050129528A1 (en) * 2000-12-12 2005-06-16 Borgwarner Inc. Variable displacement vane pump with variable target reguator
US20060104823A1 (en) * 2002-04-03 2006-05-18 Borgwarner Inc. Hydraulic pump with variable flow and variable pressure and electric control
CN100462552C (zh) * 2004-09-22 2009-02-18 山东交通学院 单作用叶片式二次元件
US20100296956A1 (en) * 2009-05-20 2010-11-25 Hoehn Richard T Variable displacement pumps and vane pump control systems
US9878786B2 (en) 2014-12-04 2018-01-30 Elwha Llc System and method for operation and management of reconfigurable unmanned aircraft
US9902491B2 (en) 2014-12-04 2018-02-27 Elwha Llc Reconfigurable unmanned aircraft system
EP3361099A1 (en) * 2017-02-10 2018-08-15 Entecnia Consulting, S.L.U. Method of manufacturing and assembling a pump and vacuum pump
CN108412760A (zh) * 2018-04-11 2018-08-17 王长健 变量泵排量的调节方法及变量泵
CN110131160A (zh) * 2019-05-29 2019-08-16 河南航天液压气动技术有限公司 一种变排量叶片泵
US12092070B1 (en) 2023-04-05 2024-09-17 Dana Motion Systems Italia S.R.L. Adjustable distribution plate for an axial piston assembly

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2914282C2 (de) * 1979-04-09 1983-01-05 Mannesmann Rexroth GmbH, 8770 Lohr Stützkörper für den verstellbaren Laufring von Hydropumpen
JPS5986386U (ja) * 1982-12-02 1984-06-11 トヨタ自動車株式会社 可変容量形ベ−ンポンプ
DE3518090C2 (de) * 1985-05-20 1987-03-05 Mannesmann Rexroth GmbH, 8770 Lohr Hydraulikpumpe
DE3725353A1 (de) * 1987-07-30 1989-02-16 Rexroth Mannesmann Gmbh Radialkolbenmaschine, insbesondere fluegelzellenmaschine

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2406482A (en) * 1942-04-27 1946-08-27 Hydraulic Dev Corp Inc Hydraulically controlled machine tool
US2949081A (en) * 1956-04-25 1960-08-16 Hydro Aire Inc Pumping cavity for rotary vane pump
US3107628A (en) * 1959-04-15 1963-10-22 Racine Hydraulics & Machinery Vane type pump
US3252423A (en) * 1964-01-10 1966-05-24 Continental Machines Variable volume vane type pump
US3523746A (en) * 1968-10-31 1970-08-11 Racine Hydraulics Inc Fluid translating device

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2612115A (en) * 1948-04-06 1952-09-30 Thompson Grinder Co Vane pump and vane therefor
US2600633A (en) * 1949-02-05 1952-06-17 Heil Co Constant volume variable speed driven vane pump
US2975717A (en) * 1959-06-12 1961-03-21 Racine Hydraulics & Machinery Flow governing hydraulic system
US3465682A (en) * 1967-10-26 1969-09-09 Koehring Co Variable volume pump

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2406482A (en) * 1942-04-27 1946-08-27 Hydraulic Dev Corp Inc Hydraulically controlled machine tool
US2949081A (en) * 1956-04-25 1960-08-16 Hydro Aire Inc Pumping cavity for rotary vane pump
US3107628A (en) * 1959-04-15 1963-10-22 Racine Hydraulics & Machinery Vane type pump
US3252423A (en) * 1964-01-10 1966-05-24 Continental Machines Variable volume vane type pump
US3523746A (en) * 1968-10-31 1970-08-11 Racine Hydraulics Inc Fluid translating device

Cited By (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4222718A (en) * 1978-03-09 1980-09-16 Rexnord Inc. Linear motion thrust block for hydraulic pumps and motors
US4340338A (en) * 1978-03-09 1982-07-20 Rexnord Inc. Hydraulic pressure biased linear motion thrust block for hydraulic pumps and motors
US4566870A (en) * 1982-11-02 1986-01-28 Itt Industries, Inc. Adjustable vane-type pump
US4770616A (en) * 1982-11-20 1988-09-13 Itt Industries, Inc. Variable vane-type pump
US4715180A (en) * 1984-01-13 1987-12-29 Dynamic Hydraulic Systems, Inc. Hydraulic lift mechanism
US4851723A (en) * 1988-08-01 1989-07-25 Westinghouse Electric Corp. Coolant pump system for variable speed generators
US5033265A (en) * 1989-03-08 1991-07-23 Sundstrand Corporation Coaxial hydraulic actuator system
US5236319A (en) * 1991-05-15 1993-08-17 Mannesmann Rexroth Gmbh Vane pump
US6457946B2 (en) * 1999-12-23 2002-10-01 Daimlerchrysler Ag Regulatable pump
US20020114708A1 (en) * 2000-12-12 2002-08-22 Hunter Douglas G. Variable displacement vane pump with variable target regulator
US7674095B2 (en) 2000-12-12 2010-03-09 Borgwarner Inc. Variable displacement vane pump with variable target regulator
US6896489B2 (en) * 2000-12-12 2005-05-24 Borgwarner Inc. Variable displacement vane pump with variable target regulator
US20050129528A1 (en) * 2000-12-12 2005-06-16 Borgwarner Inc. Variable displacement vane pump with variable target reguator
US20060104823A1 (en) * 2002-04-03 2006-05-18 Borgwarner Inc. Hydraulic pump with variable flow and variable pressure and electric control
US7018178B2 (en) 2002-04-03 2006-03-28 Borgwarner Inc. Variable displacement pump and control therefore for supplying lubricant to an engine
US20060127229A1 (en) * 2002-04-03 2006-06-15 Borgwarner Inc. Variable displacement pump and control therefor
US7396214B2 (en) 2002-04-03 2008-07-08 Borgwarner Inc. Variable displacement pump and control therefor
US20030231965A1 (en) * 2002-04-03 2003-12-18 Douglas Hunter Variable displacement pump and control therefor
US7726948B2 (en) 2002-04-03 2010-06-01 Slw Automotive Inc. Hydraulic pump with variable flow and variable pressure and electric control
CN100462552C (zh) * 2004-09-22 2009-02-18 山东交通学院 单作用叶片式二次元件
US20100296956A1 (en) * 2009-05-20 2010-11-25 Hoehn Richard T Variable displacement pumps and vane pump control systems
US9902491B2 (en) 2014-12-04 2018-02-27 Elwha Llc Reconfigurable unmanned aircraft system
US9878786B2 (en) 2014-12-04 2018-01-30 Elwha Llc System and method for operation and management of reconfigurable unmanned aircraft
US9919797B2 (en) 2014-12-04 2018-03-20 Elwha Llc System and method for operation and management of reconfigurable unmanned aircraft
EP3361099A1 (en) * 2017-02-10 2018-08-15 Entecnia Consulting, S.L.U. Method of manufacturing and assembling a pump and vacuum pump
WO2018145925A1 (en) * 2017-02-10 2018-08-16 Entecnia Consulting, S.L.U. Method of manufacturing and assembling a pump and vacuum pump
CN108412760A (zh) * 2018-04-11 2018-08-17 王长健 变量泵排量的调节方法及变量泵
CN108412760B (zh) * 2018-04-11 2020-03-06 杭州中荷智慧城市科技有限公司 变量泵排量的调节方法及变量泵
CN110131160A (zh) * 2019-05-29 2019-08-16 河南航天液压气动技术有限公司 一种变排量叶片泵
US12092070B1 (en) 2023-04-05 2024-09-17 Dana Motion Systems Italia S.R.L. Adjustable distribution plate for an axial piston assembly

Also Published As

Publication number Publication date
DE2357182A1 (de) 1975-05-22
DE2357182C2 (de) 1985-05-23
JPS5080509A (enrdf_load_stackoverflow) 1975-06-30
JPS58108288U (ja) 1983-07-23

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