Motive Fluid Bypass To Or From Assembly Patents (Class 91/486)
  • Patent number: 11009015
    Abstract: A hydraulic motor apparatus includes a motor housing engaged to an end cap having a first porting system and an adapter connected to an external surface of the end cap and having a second porting system. A filter may be attached to the adapter and connected to the second porting system and a pressure reducing valve in the adapter is connected to the second porting system. The assembly may also include a controller operatively connected to the pressure reducing valve and system sensors measuring parameters affected by the output of the hydraulic motor apparatus, whereby the pressure reducing valve is operatively controlled by the controller in response to input from the system sensors.
    Type: Grant
    Filed: November 8, 2018
    Date of Patent: May 18, 2021
    Assignee: Hydro-Gear Limited Partnership
    Inventor: Nathan W. Bonny
  • Patent number: 9638180
    Abstract: An axial piston machine of swash plate design includes cylinder bores with respective longitudinal axes that are arranged at an acute angle with the rotational axis and that approach the rotational axis radially in the direction of their control plate-side ends. For each cylinder bore, a point of action of a resulting hydrostatic relieving force, which acts on the cylinder barrel, of the hydrostatic sliding bearing is spaced apart radially with regard to the rotational axis of the cylinder barrel further than a point of intersection of the longitudinal axis of the cylinder bore with the cylinder barrel-side bearing face of the hydrostatic sliding bearing.
    Type: Grant
    Filed: May 8, 2014
    Date of Patent: May 2, 2017
    Assignee: Robert Bosch GmbH
    Inventors: Manuel Sell, Frank Zehnder, David Breuer
  • Patent number: 9488050
    Abstract: A hydraulic machine includes oscillating radial cylinders close to an external shell of a crown or star of cylinder-piston groups. The pistons of the groups are made sliding on a crank shaft with throw or on interposed concentric elements, which create an alternative movement in the oscillating radial cylinders. The oscillating cylinders are placed in contact with a spherical oscillation surface made on a body or shell of the hydraulic machine. A passage of the hydraulic liquid to and from the oscillating radial cylinder, to create feeding and discharge of the cylinder, is formed through at least a flat lateral external surface on the side of the oscillating cylinder, parallel to an oscillation plane of the cylinders, to and from a feeding channel on a lateral body or cover of the hydraulic machine.
    Type: Grant
    Filed: November 9, 2011
    Date of Patent: November 8, 2016
    Assignee: R. & D. S.R.L.
    Inventor: Piercelestino Pecorari
  • Patent number: 7145764
    Abstract: A console unit includes a substrate extending along a virtual plane. A support extends rearward from the front end. The substrate is received on the support. A console is connected to the front end of the support for relative rotation around a rotation axis intersecting the virtual plane. The console is allowed to occupy a larger space even if the substrate is reduced in size. The visibility of the console cannot be degraded irrespective of a reduced size of the substrate. Other components may be positioned adjacent the console unit. Replacement of the component is often required without detaching the console. The console is allowed to retreat from the path of movement of the component based on the rotational movement. Interference can reliably be prevented between the console unit and the other component during replacement of the other component.
    Type: Grant
    Filed: February 19, 2004
    Date of Patent: December 5, 2006
    Assignee: Fujitsu Limited
    Inventor: Hiroshi Hidaka
  • Patent number: 6796774
    Abstract: An axial piston engine (1), including a housing (2) in whose inner compartment (4) a cylinder drum (17) and a swash plate (26) located axially adjacent thereto are situated. Several piston bores (21), which extend approximately parallel to the central axis of the cylinder drum (17) are located in the same, pistons (23) being displaceably guided in the piston bores. The ends of the pistons facing towards the swash plate (26) are supported on the swash plate (26). A driving shaft (7) is rotatably mounted in the housing (2) and is connected to the cylinder drum in a fixed manner secured against rotation therebetween by a multitooth coupling (19) comprising teeth (43a, 44a) and tooth spaces (43b, 44b) which alternate regularly in a peripheral direction and which engage with each other.
    Type: Grant
    Filed: August 29, 2002
    Date of Patent: September 28, 2004
    Assignee: Brueninghaus Hydromatik GmbH
    Inventor: Rainer Stölzer
  • Publication number: 20030010195
    Abstract: The invention relates to an axial piston engine (1), comprising a housing (2) in whose inner compartment (4) a cylinder drum (17) and a swash plate (26) located axially adjacent thereto are situated. Several piston bores (21) which extend approximately parallel to the central axis of the cylinder drum (17) are located in the same, pistons (23) being displaceably guided in said piston bores. The ends of said pistons facing towards the swash plate (26) are supported on said swash plate (26). A driving shaft (7) is rotatably mounted in the housing (2) and is connected to an engine part in a rotationally fixed manner by a multitooth coupling (19) comprising teeth (43a, 44a) and tooth spaces (43b, 44b) which alternate regularly in a peripheral direction and which engage with each other.
    Type: Application
    Filed: August 29, 2002
    Publication date: January 16, 2003
    Inventor: Rainer Stolzer
  • Patent number: 6038958
    Abstract: A pressure transformer is provided having a housing, with a rotating group disposed therein, an adjustable port plate is disposed between a barrel of the rotating group and a head portion of the housing. The barrel has a plurality of pistons slideably disposed in cylinders defined in the barrel. The cylinders each define a cylinder port that is in intimate contact with the port plate. The port plate has three arcuate slots defined therein and spaced from one another along a predetermined circumference. Each arcuate slot has a leading edge and a trailing edge. Likewise each of the cylinder ports has a leading edge and a trailing edge. The shape and orientation of the leading edges and trailing edges of the cylinder ports and the arcuate slots are the same. During relative rotation between the cylinder ports and the arcuate slots, the leading edges of the cylinder ports and the leading edges of the arcuate slots are radially concurrent.
    Type: Grant
    Filed: April 7, 1998
    Date of Patent: March 21, 2000
    Assignee: Noax B.V.
    Inventor: Francis J. Raab
  • Patent number: 5890412
    Abstract: A control plate (1) of a hydraulic machine having a core (2) is disclosed, which at least on its upper side (O), lying in operation against a cylinder drum, is covered with a layer of friction-reducing plastics material (3). The plastics material (3) is joined to the core (2) by means of a connecting element (8) which, as a result of interlocking engagement with the plastics material (3) and/or the core (2), takes up tensile forces substantially at right angles to the upper side (O).
    Type: Grant
    Filed: December 23, 1996
    Date of Patent: April 6, 1999
    Assignee: Danfoss A/S
    Inventors: Lars Martensen, Ove Thorb.o slashed.l Hansen
  • Patent number: 5279185
    Abstract: A radial piston hydrostatic machine disposed in a housing, a drive shaft supported in the housing and connecting through bevel pinion and gear to transmit rotation of the shaft to a cylinder barrel. The cylinder barrel provided with generally radial cylinder bores supporting pistons and mounted to rotate on a stationary ported pintle valve fixed to said housing. The cylinder barrel having an axially extending projection to support the bevel gear in spaced relationship with the end of said cylinder barrel, the bevel gear rotating with said cylinder barrel and drivingly connected to said bevel pinion. Fluid bearing means provided on the outer cylindrical surface of said pintle valve to provide a pressure field under said axially extending projection in order to counter any deflection of said bevel gear.
    Type: Grant
    Filed: September 9, 1992
    Date of Patent: January 18, 1994
    Assignee: Unipat AG
    Inventors: George D. M. Arnold, Christian H. Thoma
  • Patent number: 5094144
    Abstract: A bent axis type variable displacement hydraulic machine employing hydrostatic radial bearings for supporting hydraulic reaction forces exerted on the cylinder block. In a hydraulic machine of this sort, the number of pistons which are located in the high pressure are varies with the rotation of the cylinder block, and the resultant force of hydraulic reaction forces has an acting point at a position off the axis of the rotational shaft. Therefore, the hydrostatic radial bearings are located in such positions as to balance the moment loads which occur about the rotational shaft in relation with the acting point of the resultant force of radial hydraulic reaction forces on the drive disc of the rotational shaft. As a result, it becomes possible to lead to suppression of oil leaks from the sliding surfaces to a minimal rate and to prevent abnormal abrasive wear of each of the sliding surfaces.
    Type: Grant
    Filed: July 16, 1990
    Date of Patent: March 10, 1992
    Inventors: Yoshimichi Akasaka, Ichiro Nakamura, Yasuharu Gotoh
  • Patent number: 5094145
    Abstract: A hydraulic pump or motor having a rotary cylinder barrel formed with a plurality of cylinders in which a corresponding number of plungers are axially slidably disposed for reciprocation and a valve plate in frictional engagement with an end face of the cylinder barrel and being formed with a suction slot and a discharge slot to be communicated with the cylinders of the barrel, wherein the cylinder barrel is contained within a cavity formed in a housing having an end wall formed with an inlet passage in open communication with the suction slot of the valve plate and an outlet passage in open communication with the discharge slot of the valve plate, and a fluid control valve assembly is disposed in the end wall of the housing to permit the flow of hydraulic fluid supplied therethrough into the cavity of the housing from the outlet passage when applied with the pressure of hydraulic fluid higher than a predetermined value.
    Type: Grant
    Filed: September 11, 1990
    Date of Patent: March 10, 1992
    Assignee: Toyooki Kogyo Kabushiki Kaisha
    Inventors: Kiyoshi Wakabayashi, Masami Sakamoto, Tsuyoshi Handa, Hidenobu Yamaguchi
  • Patent number: 5035170
    Abstract: In order to eliminate leakage and provide a more efficient system, a variable displacement hydraulic apparatus (10) includes a cylinder block (12) having a plurality of hydraulic cylinders (14) therein. Each of the cylinders (14) has a hydraulic piston (16) disposed therein for reciprocating movement relative thereto. The cylinders (14) and pistons (16) are disposed about an axis (18) of the hydraulic apparatus (10). The hydraulic apparatus (10) also includes a shaft (20) operatively associated with the pistons (16) for relative driven movement therebetween and a valve block (22) having a hydraulic fluid inlet port (24) for supplying hydraulic fluid to the cylinders (14) together with a hydraulic fluid outlet port (26) for returning hydraulic fluid from the cylinders (14). The inlet and outlet ports (24 and 26) communicate with the cylinders (14) through a port plate (28) having at least one port slot (30) therethrough.
    Type: Grant
    Filed: August 30, 1989
    Date of Patent: July 30, 1991
    Assignee: Sundstrand Corporation
    Inventors: Mark S. Stroze, William G. Durtschi
  • Patent number: 4934251
    Abstract: A hydraulic axial piston motor or pump (8) of the type in which a rotor (10) has an odd-numbered plurality of cylinder ports (30) with which the arcuate ports (40,42) of a port plate (36) successively register. The port plate (36) is provided with fluid exchange ports (44,46) through which cylinders (16) communicate with a hydraulic capacitance system (81,82,84,86,93). The capacitance system (81,82,84,86,93) urges fluid into each cylinder (16) of the rotor (10) through an exchange port (44) after the associated cylinder port (30) has departed from registration with one arcuate port (40) but before the associated piston (14) has reached its bottom-dead-center position (72), and receives fluid from each cylinder through an exchange port (46) after the associated piston has begun its compression stroke but before the cylinder port has begun to register with a second arcuate port (42).
    Type: Grant
    Filed: December 16, 1988
    Date of Patent: June 19, 1990
    Assignee: Allied-Signal Inc.
    Inventor: Brian P. Barker
  • Patent number: 4920859
    Abstract: A hydraulic radial piston power transmitting assembly including a hoursing and a back plate with a fixed pintle attached to the back plate which rotatably supports a cylinder block with radially spaced bores and pistons therearound, a drive shaft which drives the cylinder block through a coupling means, a cam ring surrounding the cylinder block which is pivotally connected to the housing allowing limited movement of the ring to vary the piston stroke in the cylinder block and cam ring positioning means including a rotating control arm mounted in the housing, swivel means attached to the cam ring with a spherical surface thereon and a sleeve means slidably received on the control arm means including a lateral bore for sliding receipt of the spherical surface of the swivel means to accommodate the locus of points which define the cam ring's various displacement positions.
    Type: Grant
    Filed: August 1, 1986
    Date of Patent: May 1, 1990
    Assignee: Eaton Corporaton
    Inventors: Steven T. Smart, William M. Puls, David L. Hansen
  • Patent number: 4890539
    Abstract: A control arrangement to control the flow of fluid through pumps, motors, transmissions, engines has an eccentric shoulder assembled into a respective thrust chamber in a portion of the housing to be pressed against the rotary seal face of the rotor of the device. Such arrangements are known from some of my earlier patents and have served satisfactorily, but with the desire to improve the pressures further, it has been found, that arrangements are required to prevent the control body from slight rotation, under which it otherwise would stick. The arrangement provides the means to prevent the rotation and sticking by defining a relationship between eccentricities and gravity centers in order to reduce the tendency to stick. Pins and pins with eccentric and adjustable portions are also used to prevent the tendency to stick and so are pluralities of eccentrically arranged individual thrust chambers and control body portions.
    Type: Grant
    Filed: February 1, 1988
    Date of Patent: January 2, 1990
    Inventor: Karl Eickmann
  • Patent number: 4793239
    Abstract: In an axial piston motor or pump the cylinder barrel is mounted on a medial shaft which has a shoulder which axially bears against the front end of the rotor barrel. The rear end of the medial shaft is radially borne in a housing portion. The front portion of the medial shaft is provided with a bearing member of an axial thrust bearing for support on a respective axial thrust bearing member in the housing. On the rear end of the rotary barrel an axially selfthrusting control body is provided to seal the flow of fluid to and from the cylinders of the rotary barrel. The control body presses against the rotary barrel, the rotary barrel presses against the bearing of the medial shaft and the thrust bearing member of the shaft bears on the thrust bearing member of the housing. As a result thereof the cylinders in the rotary barrel can be straight through bores. The manufacturing of the rotor barrel is thereby simplified and the flow acceleration losses of former sack-bare bore type cylinders are prevented.
    Type: Grant
    Filed: April 24, 1987
    Date of Patent: December 27, 1988
    Inventor: Karl Eickmann
  • Patent number: 4791858
    Abstract: A piston machine, particularly a radial piston machine which includes a pintle supporting a rotor which has a plurality of radially extending bores in which radial pistons are guided. These bores are in communication with control chambers formed in the pintle. One of the chambers is a high-pressure chamber and the other is a low-pressure chamber. Pre-control grooves and additional passages are provided at the control chambers to prevent, during the operation of the radial piston machine the occurrence of pressure shocks at the inner and outer dead centers.
    Type: Grant
    Filed: November 23, 1987
    Date of Patent: December 20, 1988
    Assignee: Robert Bosch GmbH
    Inventor: Gerhard Nonnenmacher
  • Patent number: 4788902
    Abstract: A thrust hydrostatic bearing device for use in an axial piston machine includes a bearing sleeve fitted into a housing cover for rotatably supporting a drive shaft through a bearing and having a plurality of hydrostatic pads. The hydrostatic pads are disposed at locations which are symmetrical with respect to an axis lying in a cross-section taken perpendicular to the drive shaft, and these pads increase the performance and durability of the thrust hydrostatic bearing device for use in an axial piston machine.
    Type: Grant
    Filed: August 24, 1987
    Date of Patent: December 6, 1988
    Assignees: Hitachi Ltd., Hitachi Construction Machinery
    Inventors: Yoshimichi Akasaka, Ichiro Nakamura, Ken Ichiryu, Eiji Kometani, Yasuharu Gotoh
  • Patent number: 4782737
    Abstract: A fluid machine such as a pump, compressor, engine, motor or transmission has working chambers in a rotor and a central rotor-hub is provided in the rotor for the reception of a control pintle therein. The control pintle has control ports for the control of flow of fluid into and out of the working chambers of the rotor. Pressure fields form in the clearance between the rotor hub and the control pintle especially around the control ports. Leakage flows from the pressure fields through portions of the clearance between the rotor--hub and the control pintle which reduces the efficiency of the machine. Therefore means are provided in the control pintle to press those portions of the faces of the rotor hub and of the control pintle, which have those local pressure fields, together or to narrow the clearance between these faces in the respective areas where those pressure fields are located in order to reduce the leakage through the clearance between the faces of the rotor hub and the control pintle.
    Type: Grant
    Filed: December 23, 1986
    Date of Patent: November 8, 1988
    Inventor: Karl Eickmann
  • Patent number: 4765228
    Abstract: With the object of improving the flushing arrangement in an axial piston machine for use in a closed-circuit hydrostatic drive, having a control member (18) that controls the working cycle of the axial piston machine (1) and having a circuit flushing arrangement (31) that includes a flushing valve (33) that is arranged in the control member (18), can be acted on by high pressure and connects the low pressure line (37 or 38) with a return line (44), the valve body of the flushing valve (33) comprises a cylindrical sleeve valve (34) displaceably mounted in a guide bore (35) directly between the high pressure duct (38) and the low pressure duct (37) in the control member (18), the guide bore being connected with the free space (23) of the housing (2) of the axial piston machine in the region of the sleeve valve (34) by a connecting duct (44).
    Type: Grant
    Filed: July 16, 1987
    Date of Patent: August 23, 1988
    Assignee: Hydromatik GmbH
    Inventor: Ludwig Wagenseil
  • Patent number: 4723477
    Abstract: A control arrangement to control the flow of fluid through pumps, motors, transmission, engines has an eccentric shoulder assembled into a respective thrust chamber in a portion of the housing to be pressed against the rotary seal face of the rotor of the device. Such arrangements are known from some of my earlier patents and have served satisfactorily, but with the desire to improve the pressures further, it has been found, that arrangements are required to prevent the control body from slight rotation, under which it otherwise would stick. The arrangement provides the means to prevent the rotation and sticking by defining a relationship between eccentricities and gravity centers in order to reduce the tendency to stick. Pins and pins with eccentric and adjustable portions are also used to prevent the tendency to stick and so are pluralities of eccentrically arranged individual thrust chambers and control body portions.
    Type: Grant
    Filed: November 27, 1985
    Date of Patent: February 9, 1988
    Inventor: Karl Eickmann
  • Patent number: 4710107
    Abstract: A variable displacement axial piston device has a movable swashblock, the front face of which is engaged by shoes pivotally mounted on the end of pistons operating in a plurality of cylinders formed in a cylinder barrel. The rear of the swashblock has a pair of arcuate bearing surfaces and a support is provided in the device for such bearing surfaces. A pair of arcuate bearings are disposed between the support and the swashblock bearing surfaces. At least the one swashblock bearing surface that is opposite the high pressure port of the device has a continuous groove that faces the respective bearing. A passageway is formed internal of the swashblock and terminates in the groove. An opening with an orifice is provided in the front face of the swashblock leading to the passageway from a position that is axially aligned with the one bearing surface and in the path of the shoes as they pass over the front face of the swashblock.
    Type: Grant
    Filed: April 15, 1986
    Date of Patent: December 1, 1987
    Assignee: The Oilgear Company
    Inventor: Kerry R. Kanies
  • Patent number: 4703682
    Abstract: The invention relates to an adjustable axial piston engine having spaced apart end walls with a shaft extending between the end walls. A rotary carrier is attached to the shaft adjacent one of the end walls and an oblique adjusting plate is mounted adjacent the other end wall. A piston-cylinder unit extends between the carrier and the oblique plate. A pivot axis for the oblique plate includes a bearing arrangement between the plate and the adjacent end wall. A servo unit for adjustably rotating the plate about the pivot axis is provided between the plate and the adjacent end wall.
    Type: Grant
    Filed: May 21, 1986
    Date of Patent: November 3, 1987
    Assignee: Danfoss A/S
    Inventor: Gunnar L. Hansen
  • Patent number: 4664018
    Abstract: In an axial piston motor or pump the cylinder barrel is mounted on a medial shaft which has a shoulder which axially, bears against the front end of the rotor barrel. The rear end of the medial shaft is radially borne in a housing portion. The front portion of the medial shaft is provided with a bearing member of an axial thrust bearing for support on a respective axial thrust bearing member in the housing. On the rear end of the rotary barrel an axially selfthrusting control body is provided to seal the flow of fluid to and from the cylinders of the rotary barrel. The control body presses against the rotary barrel, the rotary barrel presses against the shoulder of the medial shaft and the thrust bearing member of the shaft bears on the thrust bearing member of the housing. As a result thereof the cylinders in the rotary barrel can be straight through bores. The manufacturing of the rotor barrel is thereby simplified and the flow acceleration losses of former bag bore type cylinders are prevented.
    Type: Grant
    Filed: December 5, 1984
    Date of Patent: May 12, 1987
    Inventor: Karl Eickmann
  • Patent number: 4602554
    Abstract: The invention is concerned with an axial piston machine, preferably an axial piston pump of the inclined disc or skew axis type, with a cylinder (9) which rotates about an axis of rotation and in which, on a pitch circle, several pistons (8) are movably guided in piston bores (11) extending substantially along the axis of rotation (3), by means of an inclined or driving disc, or the like, the piston bores (11) opening at the face of the cylinder (9) which is remote from the inclined or driving disc (5), the face resting against a control surface (13) in which there are arranged control openings (14), positioned on the pitch circle of the pistons (8) which, in set positions of rotation of the cylinder (9) are covered by the openings of the piston bores (11), loading cylinders (24) being distributed over the circumference and acting upon the cylinder (9) against the control surface (13), and of which loading cylinders the working spaces are connected, by means of connecting channels (27), each with a respective
    Type: Grant
    Filed: March 26, 1985
    Date of Patent: July 29, 1986
    Assignee: Hydromatik GmbH
    Inventors: Ludwig Wagenseil, Manfred Lotter
  • Patent number: 4550644
    Abstract: In a fluid machine, wherein fluid flows through working chambers, as in pumps, compressors, motors, transmissions, a rotor and a drive shaft are revolvingly borne in the housing of the machine. Since slight departures of the axes of the rotor and shaft from each other might result in wearing of faces or in widened clearances in the machine, the shaft and rotor are coupled flexibly. The coupling is managed by providing the drive shaft with arms or fingers and the rotor with gaps whereby the gaps are extending into the axially seen medial rotor portion. The arms or fingers are engaging the walls of the gaps in the mentioned medial rotor portion, whereby tilting components of forces, which might occur, when the coupling would be on an axial end of the rotor, are prevented.
    Type: Grant
    Filed: January 31, 1984
    Date of Patent: November 5, 1985
    Inventor: Karl Eickmann
  • Patent number: 4465394
    Abstract: A ball-jointed bearing arrangement of the piston heads in an axial piston machine within a drive flange wherein a bearing member formed of a material with good antifriction properties for receiving a piston head is seated in a recess of the drive flange whereby all bearing members are covered by a covering plate which is detachably fastened to the drive flange. The bearing member is formed of a spherically indented cup of a flat material, such as sheet metal, which is inserted into the respective recess, which recesses conform in shape, pitch circle and distribution to the piston heads, however, are constructed in conformance with the thickness of the respective spherical dished cup deeper and larger in diameter, and in which the covering plate is traversed by the piston heads and is fastened on the side of the drive flange towards the piston heads.
    Type: Grant
    Filed: July 16, 1981
    Date of Patent: August 14, 1984
    Assignee: Brueninghaus Hydraulik GmbH
    Inventor: Heinz Berthold
  • Patent number: 4444092
    Abstract: This invention relates to hydraulic pumps. The pump includes essentially a casing (1), a barrel (3) capable of rotating on a slide face (2), the barrel comprising a plurality of pistons (16, 17) sliding in a reciprocating manner in cylinders (9, 10) provided in the casing, the pump being characterized essentially by the fact that it comprises structures (59, 54, 50, 52, 53) for sequentially applying the pressure prevailing in the cylinder on a given portion between a bearing block (26) made in the casing (1) and the part of said barrel (3) cooperating with the bearing block (26). The pump finds a particularly advantageous application in the area of those which must rotate at very high speed, for example in aeronautics.
    Type: Grant
    Filed: April 2, 1982
    Date of Patent: April 24, 1984
    Assignee: Messier-Hispano-Bugatli (SA)
    Inventor: Marcel Schott
  • Patent number: 4382399
    Abstract: A support for the drive shaft of an axial-piston machine of inclined axis construction (pivoted or tilted drum) for pressurized fluids, consisting of at least one axially loadable bearing arranged at respectively, the piston side and at the drive side with stationary outer rings arranged in a bearing housing and a load-receiving direction located the same towards the piston side. At least the outer ring of one of the bearings is axially supported on the bearing housing and at least one of the inner rings of the bearing is supported on the drive shaft at the piston side shaft and whereby, for balancing the axial components of the piston forces effective between the bearings, there is provided at least one pressure cylinder unit with a balancing piston which is acted upon with pressurized fluid from the pressure side of the machine.
    Type: Grant
    Filed: November 24, 1980
    Date of Patent: May 10, 1983
    Assignee: Hydromatik GmbH
    Inventor: Manfred Lotter
  • Patent number: 4168653
    Abstract: An axially oriented variable displacemnt pistoned device adaptable for use as motor and having a pivoted swash plate angularly positionable for establishing displacement of the device is fitted with externally mounted low pressure hydraulic actuators operably connected with the swash plate for operation thereof. Adjustable stops are provided in the device body to limit travel of the swash plate under urging of the low pressure hydraulic actuators.
    Type: Grant
    Filed: December 20, 1976
    Date of Patent: September 25, 1979
    Assignee: Caterpillar Tractor Co.
    Inventors: Allyn J. Hein, Gerald D. Hall
  • Patent number: 4077305
    Abstract: A hydraulic piston motor, preferably a hydrostatic motor of the axial-piston type, has its pistons hydrostatically urged against a surface which is moved relative to or with the pistons in order to reduce static frictional retardation of the pistons upon starting the motor.
    Type: Grant
    Filed: July 29, 1976
    Date of Patent: March 7, 1978
    Assignee: Linde Aktiengesellschaft
    Inventor: Hans Waldemar Stuhr
  • Patent number: 4074782
    Abstract: A skid steer loader comprising an improved loader main frame and including an operator's compartment designed to present a low profile vehicle particularly suitable for low clearance applications. A improved hydraulic system for the vehicle includes a new arrangement of an implement pump interconnected with the hydraulic drive pumps of the steering system of the vehicle. An internal connection between the drive pumps and the implement pump substantially improves the flow of hydraulic fluid through the system by providing an internal passage for flow of excess hydraulic fluid from a drive pump to the implement pump to supply the implement pump with inlet fluid.
    Type: Grant
    Filed: February 2, 1976
    Date of Patent: February 21, 1978
    Assignee: Clark Equipment Company
    Inventor: James J. Bauer
  • Patent number: 4033237
    Abstract: A floating bearing ring is disposed between each bearing surface of the fixed pin and the guide member for the pistons and in spaced relation to each. The clearance of the bearing rings from the pin bearing surfaces is less than the clearance of the bearing rings from the guide member. Upon heating of the pin, the bearing rings simultaneously heat up to the same temperature to maintain their clearance. This prevents seizing of the bearing rings and, in turn, the guide member on the pin during use.
    Type: Grant
    Filed: October 29, 1974
    Date of Patent: July 5, 1977
    Assignee: Sulzer Brothers Limited
    Inventor: Peter Rutz