US3479963A - Fluid device - Google Patents

Fluid device Download PDF

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Publication number
US3479963A
US3479963A US676124A US3479963DA US3479963A US 3479963 A US3479963 A US 3479963A US 676124 A US676124 A US 676124A US 3479963D A US3479963D A US 3479963DA US 3479963 A US3479963 A US 3479963A
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United States
Prior art keywords
valve plate
pressure
fluid
barrel
port
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
US676124A
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English (en)
Inventor
Gerald Randa
William T Stephens
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.)
Borg Warner Corp
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Borg Warner Corp
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Publication date
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Publication of US3479963A publication Critical patent/US3479963A/en
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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
    • F01B3/00—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F01B3/0032—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block
    • F01B3/0044—Component parts, details, e.g. valves, sealings, lubrication
    • F01B3/0052—Cylinder barrel
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
    • F01B3/00—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F01B3/0032—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block
    • F01B3/0044—Component parts, details, e.g. valves, sealings, lubrication
    • F01B3/0055—Valve means, e.g. valve plate

Definitions

  • a fluid pressure device having a rotating cylinder barrel, a port block and a valve plate between said cylinder barrel and the port block.
  • the device including intake and discharge ports in the valve plate including a seal or piston assembly surrounding said ports and responsive to fluid pressure to provide a seal between the valve plate.
  • valve plate mounted between the cylinder barrel of the pump or motor and a port block, the valve plate being mounted on said port block in a manner allowing slight movement of the valve plate with respect to the port block.
  • the valve plate includes intake and discharge ports surrounded by arcuate shaped counterbores in which are mounted piston assemblies having a piston member movable in said counterbore in the valve plate and in contact with said port block. Fluid pressure urges said piston member into engagement with said port 'block whereby a fluid seal is maintained regardless of misalignment of the parts of the pump or motor.
  • FIGURE 1 is a cross-sectional view through a fluid pump or motor structure embodying the present invention
  • FIGURE 2 is an enlarged sectional view of a portion of FIGURE 1;
  • FIGURE 3 is a view taken along the line 33 of FIGURE 1;
  • FIGURE 4 is a view taken along the line 44 of FIGURE 1;
  • FIGURE 5 is a view taken along the line 55 of FIGURE 1;
  • FIGURE 6 is a view taken along the line 66 of FIGURE 1;
  • FIGURE 7 is a cross-sectional view of a modified form of the invention.
  • FIGURE 8 is a view taken along the line 8-8 of FIGURE 7.
  • FIGURE 1 a fluid pump or motor mechanism 10 is illustrated. If the mechanism of FIGURE 1 is to operate as a pump, shaft 11 serves as a drive shaft to rotate a cylinder barrel 12 of the pump 10. If the mechanism is used as a fluid motor, shaft 11 would be the driven or output shaft of the driving motor 10.
  • cylinder barrel 12 Provided in the cylinder barrel 12 are a plurality of cylinders 13 each receiving a fluid piston 14. Cylinder liners or bushings 14a are provided in which pistons 14 reciprocate.
  • the pump mechanism is contained within a housing 15; a thrust bearing 16 is mounted within the housing receiving the end of the driving shaft 11.
  • a fixed swash plate 20 is provided for the pump.
  • the present invention is primarily designed to work with variable displacement pumps having a variable angle swash plate although the fixed swash plate is illustrated to simplify the description.
  • a retaining clamp 21 is mounted on the swash plate 20, for example, by bolts 22.
  • the retaining clamp 21 engages a plate 24 which in turn engages slippers 25 provided on the ball shaped end of the pistons 14.
  • the swash plate 20 causes the pistons 14 to reciprocate within the cylinders 13 to alternatively take in and displace fluid from the cylinders.
  • a port block is provided on one end of the housing 15 to enclose the housing and may be secured to the housing in any known manner.
  • the port block 30 has a central bore 31 through which the shaft 11 passes.
  • Mounted between the cylinder barrel 12 and the port block 30 is a barrel plate 35 which is drivingly connected to shaft 11 to rotate with cylinder barrel 12 and a nonrotating valve plate 36.
  • the cylinder barrel 12 may be manufactured with the barrel plate 35 integral with the cylinder barrel 12.
  • the valve plate 36 as can be seen by reference to FIG- URE 3 includes a bore 37 and a slot 38 on opposite sides thereof. Pins 40 mounted in the port block 30 are received in the bore 37 and the slot 38 of the valve plate 36. The pins 40 locate the valve plate within the assembly but allow slight relative movement of the valve plate 36 with respect to port block 30 to compensate for misalignment.
  • a pair of counter bores 41 and 42 are formed in the valve plate 36 which are intercepted by small bores 43. Received Within the counter bores 41 are pressure buttons 48 and resilient means 49 comprising O-rings which in the FIGURE 1 construction provide a pressure balancing function in the pump to be described later.
  • vlave plate 36 Also provided in the vlave plate 36 (see FIGURE 3) is a pair of arcuate passages or ports and 56 which constitute the fluid inlet and outlet or pressure passages for the pump. Mating passages, not illustrated, are formed in the port block 30 and are suitably connected to the output line from the pump and the inlet line from the sump.
  • a piston or sealing assembly is provided for each of the arcuate ports 55 and 56 although a piston assembly is necessary only for the high pressure port (the outlet port if the device is acting as a pump or the inlet port if the device is acting as a motor).
  • the piston assembly 60 surrounds the ports and is mounted on the periphery of the ports 55 and 56 within the valve plate 36 in a stepped area 58 having a pressure responsive surface 59.
  • the piston assembly 60 for each of the arcuate ports comprises a piston member 61, a pressure or resilient member 62 and a retainer 63 each having an arcuate kidney shape similar to ports 55 and 56.
  • the piston member 61 engages the port a material having sufficient resistance to deformation to maintain a precise area engaging the port block as defined by the size of the counterbore in which the piston is mounted whereby the piston will maintain a fluid seal between the valve plate and the port block and will not be deformed to exceed the area limit defined by the bore and extrude into the area between valve plate 36 and port block 30.
  • the pressure member 62 is comprised of rubber like or other elastic material which may deform when subjected to fluid pressure and establish a fluid seal between the piston 61 and bore 58.
  • pressure member 62 is primarily a sealing member and acts along with piston member 61 as an annular piston in response to fluid pressure and may or may not deform depending upon the pressure involved and the composition of the material used.
  • Other shapes of pressure members such as member 62 may be used as, for example, a common ring shape.
  • the piston assembly 60 is constructed such that when the pump is assembled deformation of the pressure member 62 takes place thereby providing a pressure loading characteristic within the pump so that a certain predetermined sealing force between piston member 61 and the port block exists.
  • barrel plate 35 comprises a plate having a series of kidney shaped ports 70 with each port 70 connecting with one of the cylinders 13.
  • the ports 70 are arcuately shaped as can be seen in FIG- URE 4 and are generally of a smaller radial dimension than the cylinders 13 as can be seen in FIGURE 1, thus providing an area 76 on the barrel plate 35 which in effect partially closes the end of the cylinders 13.
  • the ports 70 may be widened to the same radial dimension as cylinder 13, if desired, providing thrust bearing 16 has the capacity for the increased pressure loading which would be required.
  • the barrel plate 35 on the side adjacent the valve plate 36 has relieved areas 72 and 73 which form raised areas 74 surrounding the ports 70 and a series of raised areas 75 around the outer periphery of the barrel plate.
  • raised areas 76 are provided surrounding the ports 70 and a series of radial raised ribs 71 are provided extending to the outer periphery of the barrel plate 35. As in the case of the areas on the other side of the barrel plate by restricting the raised areas 76 provides a higher force per square inch ratio to insure a good fluid seal around the ports 70.
  • the ribs 71 are formed to support the barrel plate 35 and prevent warpage of the plate under high fluid pressures.
  • the barrel plate of the subject device has kidney shaped ports 70 which extend through the barrel plate 35.
  • An optional construction is to have the arcuate port such as port 70 on the side of the barrel plate adjacent the cylinder barrel dished out to generally conform to the circular shape of the cylinders in the cylinder barrel.
  • pump efficiency is maintained while at the same time the manufacture of the barrel plate is greatly simplified since the machining required to form the circular dished out shape around the port 70 is eliminated.
  • a retainer 82 is provided which is splined on the drive shaft 11.
  • the retainer 82 engages a shoulder on the shaft 11 and the cylinder barrel is assembled to the shaft 11 and retained in position by the retainer 82.
  • Arcuate areas 83 are provided on the retainer 82 to provide clearance for the pistons 14.
  • the retainer 82 is shaped with arcuate areas 83 such that the retainer 82 engages the ends of bushings 14a and serves to positively secure bushings 14a in the cylinders 13.
  • pistons 14 will move in one direction of increasing displacement as they pass the arcuate port 55 for example, so as to draw fluid into the cylinder through port 55 and will move in the direction of decreasing displacement as they pass the arcuate port 56, for example, to supply fluid pressure through port 56.
  • the fluid pressure in pressure or discharge port 56 will deform pressure member 62 of the piston assembly 60 and urge the piston member 61 into engagement with the port block 30 with a force corresponding to the pressure of the fluid transmitted.
  • a similar function will take place in the area of the intake port 55 although the pressure member 62 of the intake port is subjected to the intake fluid pressure.
  • valve plate 36 is mounted on the pins 40 in a manner to allow misalignment and the essential fluid seal between the valve plate 36 and the port block 30 is maintained due to the fluid pressure responsive action of the seal assembly 60.
  • the pressure buttons 48 which have been illustrated as two in number in FIGURES 3 and 7 although additional ones may be used, are provided in the valve plate in the areas between the intake and outlet ports 55 and 56. These buttons (or pistons) as well as the surfaces 59 serve a pressure balancing function in that fluid pressure in the cylinder ports is conducted through the bores 43 and urges the buttons 48 against the port block 30. Fluid pressure acts on the area defined by the circumference of the pressure buttons 48 minus the area of the bores 43 to urge the valve plate against the barrel plate and help to overcome the separating force between valve plate 36 and barrel plate 35 in the areas between the ports 55 and 56 of the valve plate 36.
  • the size of O-rings 49 is such that when the pump is assembled pressure is applied against the buttons 48 to provide a preloading function and provide a sealing force prior to the pump attaining a predetermined minimum pressure output.
  • FIGURES 7 and 8 shows a modified form of the present invention in which the pressure buttons 48 are mounted within the port block 30 and urged into engagement with the valve plate 36 by fluid pressure. Pressure is supplied from the pump outlet to bores in the port block 30 to act on the pressure buttons 48. Thus a pressure loading function is provided by the buttons 48 to help overcome the separating force between the valve plate and the barrel plate.
  • the pressure buttons 48 receive the exact fluid pressure within the cylinder 13 which is opposite the pressure buttons at any given time, thus the pressure buttons 48 in FIGURE I serve a pressure balancing function.
  • identical pump pressure is imposed on each of the pres sure buttons, thus providing a pressure loading function as distinguished from the pressure balancing function of FIGURE 1.
  • the structure of FIGURE 7 may also be constructed having a predetermined fixed pressure imposed on the buttons 48 as for example supplied by a charge pump or other source.
  • piston assembly 60 can be mounted in port block 30 (although not illustrated) rather than in the valve plate as shown in FIG- URE 1.
  • the operation of the piston assembly would be the same if mounted in port block 30.
  • the present invention provides a fluid pump or motor of increased capacity since the ports to the pump cylinders have an increased area.
  • the increased area is permitted due to the use of pressure responsive areas which serve to provide a sealing force in accordance with the fluid pressure existing in the pump ports to thereby compensate for the separating force between the valve plate and the barrel plate elements of the pump.
  • the cylinder barrel 12 may be fixedly mounted on the drive shaft 11 and misalignment problems are compensated for by the floating valve plate.
  • the cylinder barrel is mounted in a manner to provide for slight displacement or movement of the cylinder barrel to compensate for drive shaft deflection.
  • the common problem found in the prior art devices using what may be termed a floating cylinder barrel to provide for misalignment is that the heavy mass of the cylinder barrel when flexibly mounted is hard to control and under certain types of vibrations may deflect the shaft on which it is mounted creating an unbalance condition, or, in the case of a sudden strong vibration, may move to the extent to lose its seal with the barrel plate and valve plate completely.
  • a cylinder barrel having a plurality of cylinders therein with a piston reciprocal in each cylinder, a port block adjacent said barrel, a valve plate between said port block and said barrel, said valve plate being mounted for relative movement with respect to said port block, said cylinder barrel having relative rotation with respect to said valve plate and port block, said valve plate including a fluid intake and pressure port, a piston assembly mounted in a recess in said valve plate and surrounding at least one port, said piston assembly including a piston member in contact with said port block to provide a fluid seal for said port, resilient means in said piston assembly urging said piston member into engagement with said port block, said resilient means being responsive to fluid pressure in said port to urge said piston member into engagement with said port block with additional force whereby said fluid seal will be maintained under conditions of misalignment between said valve plate and said port block, said recess including a pressure responsive surface surrounding said port, and said surface acting to overcome the separating force between the cylinder barrel and said valve plate when said fluid pump or motor is in operation
  • a mechanism as claimed in claim 1 including a plurality of pressure buttons mounted in said valve plate arcuately disposed between said intake and discharge ports and adapted to receive fluid pressure from said cylinder and exert a balancing force in response thereto upon said valve plate.
  • a mechanism as claimed in claim 4 including resilient means mounted in said valve plate and urging said buttons outwardly of said valve plate to provide a preloading function.
  • a fluid pump or motor as claimed in claim 1 includ ing a barrel plate mounted between said valve plate and said cylinder barrel and in engagement with each.
  • a cylinder barrel having a plurality of cylinders therein with a piston reciprocal in each cylinder, a port block adjacent said barrel, a valve plate between said port block and said barrel, said cylinder barrel having relative rotation with respect to said valve plate and port block, said valve plate including a fluid intake and pressure port, a piston assembly surrounding each port and mounted in said valve plate, said piston assembly including a piston member in contact with said block to provide a fluid seal for said intake and pressure ports, resilient means in said piston assembly urging said piston member into engagement with said valve plate, said resilient means being responsive to fluid pressure to urge said piston member into engagement with additional force whereby said fluid seal will be maintained under conditions of misalignment between said valve plate and said cylinder barrel and including a plurality of pressure buttons mounted in said port block arcuately disposed between said intake and discharge ports of said valve plate adapted to have fluid pressure imposed thereon and exert a balancing force in response thereto upon said valve plate.
  • a mechanism as claimed in claim 9 including resilient means mounted in said port block and urging said buttons outwardly of said port block to provide a preloading function.
  • a cylinder barrel having a plurality of cylinders therein with a piston reciprocal in each cylinder, a port block member adjacent said barrel, a valve plate member between said port block member and said barrel, said valve plate mounted for relative movement with respect to said port block, said cylinder barrel having relative rotation with respect to said valve plate member and said port block member, said valve plate member including a fluid intake and pressure port, a piston assembly surrounding each port and mounted in one of said members, said piston assembly including a piston member in contact with the other of said members to provide a fluid seal for said intake and pressure ports, resilient means in said piston assembly urging said piston member into engagement with said other member, and said resilient means being responsive to fluid pressure to urge said piston into engagement with additional force whereby said fluid seal will be maintained under conditions of misalignment between said valve plate member and said port block member.
  • a fluid pump or motor as claimed in claim 13 3,051,093 8/1962 Budzich 103-162 wherein said piston assembly is mounted in a counterbore 3,175,510 3/ 1965 DAmato 103l62 in one of said members, said recess including a pressure 3,183,846 5/1965 Skinner 103162 responsive surface surrounding said intake and pressure 3,191,543 6/1965 Hann et al. 103162 ports, and said surface acting to overcome the separating force between the cylinder barrel and said valve plate FOREIGN PATENTS member when said fluid pump or motor is in operation.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Reciprocating Pumps (AREA)
  • Details Of Reciprocating Pumps (AREA)
US676124A 1967-10-18 1967-10-18 Fluid device Expired - Lifetime US3479963A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US67612467A 1967-10-18 1967-10-18

Publications (1)

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US3479963A true US3479963A (en) 1969-11-25

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Application Number Title Priority Date Filing Date
US676124A Expired - Lifetime US3479963A (en) 1967-10-18 1967-10-18 Fluid device

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US (1) US3479963A (de)
BE (1) BE722560A (de)
DE (1) DE1802178B2 (de)
FR (1) FR1585596A (de)
GB (1) GB1244640A (de)
NL (1) NL6814435A (de)
SE (1) SE343925B (de)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3641829A (en) * 1970-02-16 1972-02-15 Delavin Mfg Co Piston shoe holddown assembly
US4690036A (en) * 1984-08-16 1987-09-01 Kayaba Kogyo Kabushiki Kaisha Axial piston pump or motor with multi position swash plate
US4793239A (en) * 1978-10-25 1988-12-27 Karl Eickmann Axial piston motor or pump with an arrangement to thrust the rotor against a bearing of the shaft
US5247794A (en) * 1990-09-11 1993-09-28 Sundstrand Corporation Cylinder block positive hold-down for cold start-up
US5279205A (en) * 1992-01-15 1994-01-18 Caterpillar Inc. Axial piston fluid translating unit with sealed barrel plate
US5429482A (en) * 1991-09-11 1995-07-04 Kabushiki Kaisha Toyoda Jidoshokki Seisakusho Reciprocatory piston type compressor
US7052246B1 (en) * 1995-07-15 2006-05-30 Danfoss A/S Axial piston micropump
US20070028608A1 (en) * 2004-02-11 2007-02-08 George Kadlicko Rotary hydraulic machine and controls
CN103104477A (zh) * 2013-01-22 2013-05-15 北京工业大学 固定式纯水液压轴向柱塞泵用非对称配流盘
CN109268252A (zh) * 2017-07-18 2019-01-25 佛山市科达液压机械有限公司 液压泵配油盘的防抖动固定结构

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2533965B1 (fr) * 1982-09-30 1986-12-26 Poclain Hydraulics Sa Mecanisme a fluide sous pression, moteur ou pompe
DE4321770C1 (de) * 1993-06-30 1994-09-01 Hydromatik Gmbh Axialkolbenmaschine mit einem Steuerkörper mit wenigstens einer sphärischen Begrenzungsfläche

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2646754A (en) * 1946-10-17 1953-07-28 John W Overbeke Hydraulic fluid mechanism
US2845941A (en) * 1955-02-25 1958-08-05 Ernest E Wagner Plate valve for rotary units
US3051093A (en) * 1957-08-12 1962-08-28 New York Air Brake Co Valve plate for engine
US3175510A (en) * 1962-10-16 1965-03-30 Amato Michael A D Variable displacement pump
US3183846A (en) * 1962-12-03 1965-05-18 Lucas Industries Ltd Fluid pumps and motors
US3191543A (en) * 1962-07-27 1965-06-29 Sundstrand Corp Pump or motor device

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2646754A (en) * 1946-10-17 1953-07-28 John W Overbeke Hydraulic fluid mechanism
US2845941A (en) * 1955-02-25 1958-08-05 Ernest E Wagner Plate valve for rotary units
US3051093A (en) * 1957-08-12 1962-08-28 New York Air Brake Co Valve plate for engine
US3191543A (en) * 1962-07-27 1965-06-29 Sundstrand Corp Pump or motor device
US3175510A (en) * 1962-10-16 1965-03-30 Amato Michael A D Variable displacement pump
US3183846A (en) * 1962-12-03 1965-05-18 Lucas Industries Ltd Fluid pumps and motors

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3641829A (en) * 1970-02-16 1972-02-15 Delavin Mfg Co Piston shoe holddown assembly
US4793239A (en) * 1978-10-25 1988-12-27 Karl Eickmann Axial piston motor or pump with an arrangement to thrust the rotor against a bearing of the shaft
US4690036A (en) * 1984-08-16 1987-09-01 Kayaba Kogyo Kabushiki Kaisha Axial piston pump or motor with multi position swash plate
US5247794A (en) * 1990-09-11 1993-09-28 Sundstrand Corporation Cylinder block positive hold-down for cold start-up
US5429482A (en) * 1991-09-11 1995-07-04 Kabushiki Kaisha Toyoda Jidoshokki Seisakusho Reciprocatory piston type compressor
US5279205A (en) * 1992-01-15 1994-01-18 Caterpillar Inc. Axial piston fluid translating unit with sealed barrel plate
US7052246B1 (en) * 1995-07-15 2006-05-30 Danfoss A/S Axial piston micropump
US20070028608A1 (en) * 2004-02-11 2007-02-08 George Kadlicko Rotary hydraulic machine and controls
US7992484B2 (en) 2004-02-11 2011-08-09 Haldex Hydraulics Corporation Rotary hydraulic machine and controls
US9115770B2 (en) 2004-02-11 2015-08-25 Concentric Rockford Inc. Rotary hydraulic machine and controls
CN103104477A (zh) * 2013-01-22 2013-05-15 北京工业大学 固定式纯水液压轴向柱塞泵用非对称配流盘
CN109268252A (zh) * 2017-07-18 2019-01-25 佛山市科达液压机械有限公司 液压泵配油盘的防抖动固定结构

Also Published As

Publication number Publication date
BE722560A (de) 1969-04-01
DE1802178B2 (de) 1976-11-25
SE343925B (de) 1972-03-20
DE1802178A1 (de) 1969-05-08
FR1585596A (de) 1970-01-23
NL6814435A (de) 1969-04-22
GB1244640A (en) 1971-09-02

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