Abstract: A device for hydraulically operating a drive wheel of a wellbore tractor has, in certain embodiments, at least one cam and a rotatable assembly arranged to be rotatable with respect to the cam about an axis of rotation. The rotatable assembly has at least one piston. The device also has a chamber and at least one supply port for supplying hydraulic fluid from the chamber to the piston for energizing the piston, the supply port being arranged to be moved between first and second positions relative to the cam. In the first position, the piston can connect to the supply port and be energized to impart force against the cam for producing forward rotation of the assembly. In the second position, the piston can connect to the supply port and be energized to impart force against the cam for producing reverse rotation of the assembly. Related distributor assembly, wellbore tractor, and method are also described.

Abstract: Methods, systems, and techniques for harnessing wind energy use a tethered airfoil and a digital hydraulic pump and motor, which may optionally be a combined pump/motor. During a traction phase, a wind powered airfoil is allowed to extend a tether and a portion of the wind energy harnessed through extension of the tether is stored prior to distributing the wind energy to an electrical service. During a retraction phase, the wind energy that is stored during the traction phase is used to retract the tether. The digital hydraulic pump and motor are mechanically coupled to the tether.

Abstract: A V8 engine, each bank of which is configured such that four crank pins connected to four piston pins via a connecting rod are positioned at 90° intervals when viewed from one end of a crankshaft. The four crank pins on the bank side are offset by 60° relative to the four crank pins on the bank side when viewed from the one end.

Abstract: A pump or compressor includes a rotating shaft, and at least a first piston rod substantially perpendicular to the rotating shaft and connecting a first pair of pistons at opposite ends of the piston rod. The piston rod moves back and forth relative to the rotating shaft. The compressor additionally includes a circular eccentric, and a circular ring connected to the circular eccentric via a bearing. A drive pin engages the circular ring at a fixed position on the circular ring and engages the at least a first piston rod. When rotational motion of the shaft rotates either the first piston rod and first pair of pistons or the circular eccentric, the drive pin and the first piston rod move back and forth relative to the rotating shaft.

Abstract: Cam follower roller device, notably for an internal combustion engine fuel injection pump, comprising a tappet (12) and a roller (14) mounted to rotate on the tappet and intended to press against a cam. The tappet (12) comprises a roller support body (16), a shaft (26) for mounting the roller on the said body, and a guide sleeve (18) attached to the support body and at least partially surrounding the said body. The ends of the shaft are fixed in through-holes in the support body.

Abstract: A radial piston device includes a housing and a pintle fixed thereto that includes an inlet and an outlet, each aligned with a pintle axis. A rotor is rotatably disposed around the pintle and includes radially oriented cylinders. A piston is axially displaceable in each cylinder and includes a head defining a spherical contact surface. A thrust ring is rotatably disposed within the housing about the rotor and is in contact with each piston, such that a rotation of the rotor rotates the thrust ring. An inner surface of the thrust ring defines a toroidal contact surface. A contact location between the spherical contact surface and the toroidal contact surface varies as the rotor rotates about the pintle. A drive shaft is engaged with the rotor, such that a rotation of the rotor rotates the drive shaft.

Abstract: A variable displacement fluid working machine includes an inward ring and an outward ring, one of the inward ring and the outward ring including a rotatable ring cam coupled to a drive shaft, the other including a plurality of radially extending piston cylinders circumferentially spaced around the respective ring. The outward ring has first and second axially spaced structural members and a plurality of demountable blocks demountably retainable therebetween, the demountable blocks having either piston cylinders or ring cam segments. The demountable blocks are removable radially to facilitate maintenance and repair and to facilitate radial access to the inward ring.

Abstract: The outer periphery of the outer part of a substrate is a chamfer, and the outer part of the substrate is covered by a resin film layer. The thickness of the resin film layer at the chamfer is thicker than the locations radially further inwards from said chamfer. The surface of the resin film layer on the outer peripheral edge of the outer part is coplanar with the surface of the resin film layer further inwards. These locations act as the sliding surface the surface of the swash plate) that slides on a shoe, and compared with conventional techniques, because the resin film layer in the outer peripheral edge is thick, attrition of the portion being pressed against the shoe is suppressed. For that reason, the outer peripheral edge of the substrate and the vicinity thereof are prevented from being exposed, and seizure of the swash plate can be prevented.

Abstract: A hydraulic module includes a pump housing with an opening in communication with an exterior surface of the pump housing. A plurality of pump chambers are in communication with the opening. A plurality of pump elements correspond to the plurality of pump chambers, each of the plurality of pump elements being movable within the respective one of the pump chambers to increase the pressure in a fluid from a suction side of the pump chamber to a pressure side of the pump chamber. A motor has an output member extending into the opening of the pump housing and coupled with the plurality of pump elements. A channel is formed in the exterior surface of the pump housing. The channel establishes fluid communication between the plurality of pump chambers.

Abstract: Disclosed is a hybrid type air-compressor, which has a main body including a cylinder having upper and lower portions, a motor assembly including an eccentric shaft passing through a side surface of the main body to eccentrically rotate in the cylinder, a first communication part covering an upper portion of the cylinder of the main body and introducing air to discharge the air to the upper portion of the cylinder, a second communication part covering a lower portion of the cylinder of the main body and introducing air to discharge the air to the lower portion of the cylinder; and an air compressing means connected to the eccentric shaft of the motor assembly and vertically moving in the cylinder to alternately compress air introduced into the upper and lower portions of the cylinder.

Abstract: A lubricant supply mechanism is provided to an upper portion of a cam. A fixing member of the lubricant supply mechanism includes a recovery blade as a lubricant recovery member having lower end portions in contact with side face peripheral edge portions of the cam. The lower end portions of the recovery blade are in contact with the side face peripheral edge portions of the cam. An angle ?, which the lower end portions of the recovery blade make with a direction of rotation of the cam is smaller than 90°.

Abstract: A compressor includes a first piston, a second piston, and a crank. A first case chamber is defined by a lower surface of a first piston head, a portion of a first cylinder surface disposed below the lower surface of the first piston head, and a first case surface. A second case chamber is defined by a lower surface of a second piston head, a portion of a second cylinder surface disposed below the lower surface of the second piston head, and a second case surface. The first case chamber and the second case chamber are fluidly isolated from one another. The crank is to reciprocate the first piston head and the second piston head up and down.

Abstract: A closed type compressor of a low overall height and small vibrations provided with a structure comprising a balancing weight (142) formed of a first balancing weight (146) and a second balancing weight (148) and fixed to eccentric shaft portion (112), the first balancing weight (146) located closer to a main shaft portion (109) than the second balancing weight (148), and the second balancing weight (148) jutting out to a position further from an axis of the eccentric shaft portion (112) than the first balancing weight (146).

Abstract: A hermetic compressor includes an airtight container containing lubricating oil and having a compression element and a motor element. The compression element compresses a refrigerant by being driven by the motor element. The compression element includes a crankshaft extending in a vertical direction and having a main shaft and an eccentric part; a block forming a compression space; a piston having a cylindrical shape and reciprocating in the compression space; and a connecting rod for transmitting the rotation of the eccentric part to the piston. The piston has its center of gravity on either the upper side or the lower side in the vertical direction with respect to a plane which passes through the central axis of the piston and is perpendicular to the crankshaft.

Abstract: A diaphragm pump (1) has at least two pump heads (3) arranged around a central eccentric pump drive (2), the diaphragms (4) being drivingly connected to the eccentric pump drive (2) via connecting rods (5). The eccentric pump drive (2) has a connecting rod ring (6) to which the ends (9) of the connecting rods are connected via elastic intermediates (10).

Abstract: Disclosed is a small rotary cylinder device wherein friction loss is reduced and energy is conserved by reducing effects of a reaction force applied from cylinders to pistons, which is incorporated in a piston composite body and which linearly reciprocates, the piston composite body being eccentrically connected to a first crank shaft rotating about a shaft. Guide bearings (1c) guide linear reciprocation of first and second piston assemblies (7, 8) attached to second tube bodies (6b), which are caused by rotating a first crank shaft (5) about a shaft (4) and rotating a piston composite body (P) about the first crank shaft (5), in the radial direction of a rolling circle of second imaginary crank shafts (14a, 14b), which has a radius 2r and which is centered at the shaft (4).

Abstract: This hydraulic pump includes a frame, a pump shaft capable of being rotated by a thermal or electric motor, around an axis which is stationary with respect to the frame, an eccentric sleeve engaged with the pump shaft, and at least one stage of pistons arranged to be stationary with respect to the frame and radially extending in pump cylinders defining chambers. It comprises at least one tappet extending in a housing made in the eccentric sleeve and cooperating with at least one resilient means, having a resilience varying according to the load of the downstream circuit emerging at the level of the pump chambers, said tappet actuating means which decrease the piston stroke.

Abstract: Hydraulic pump applications sometimes require the pump to be able to provide relatively low pressure with larger amounts of fluid moved, while other applications call for relatively higher pressures but less fluid moved. The multi-speed hydraulic pump can operate at multiple speeds so as to provide multiple outputs of pressure and flow. In a two-mode version, the pump has one mode of operation that provides for lower pressure/more fluid moved and another mode of operation that provides for higher pressure/less fluid moved. Having multiple modes of operation in the pump allows for a single pump to provide greater movement or greater pressure while working within the limits of the force or speed at which the pump is actuated.

Abstract: A scotch yoke type fluid device in which the pistons are decoupled from each other is provided. Each piston of the device has its own pair of sliding surfaces and its own slider. The sliding surface of each piston is disposed on the same side of a big end bearing of a crank. The main axis of the crank is movable along a path such that the pistons are neither substantially retarded nor advanced. The effective centre of mass of the crank, piston and slider remains stationary relative to the crank axis. Each piston includes a guide for constraining the piston to move along the piston axis. An intermediate member may interconnect the piston and the slides.

Abstract: A pump includes a cylindrical main body comprising a central channel, four valve assemblies each threadedly fastened in a radial hole, first and second cavities disposed to each hole and communicating therewith, a spring activated first check valve in each first cavity, a spring activated second check valve in each second cavity, an outlet, a threaded outlet orifice communicating with the outlet, an inlet, a threaded inlet orifice communicating with the inlet, four plungers each in a plunger chamber communicating between the hole and the channel, opposite outlet and inlet tunnels, two snapping members each having a central hole and a snapping bifurcation at either bent end, the snapping bifurcation slidably put on an end of the plunger; a top cover; a bottom cover; and an eccentric shaft having one end secured to motor shaft and other portions in the main body to operatively secure to the snapping members.

Abstract: The invention relates to an eccentric pump including a frame, a pump shaft which can be driven using a driving device and is mounted to be rotatable about a main axis that is stationary relative to the frame, an eccentric sleeve which is mounted in an axially movable manner on a pump shaft section, an anti-rotation element which is effective between the pump shaft section and the eccentric sleeve), several pump elements which are stationary relative to the frame and are provided with displacement elements that can be moved in a radial direction relative to the main axis, act upon a fluid contained in swept volumes of the pump elements, and are moved against a fluid pressure by an external surface of the eccentric sleeve, and at least one spring element which acts upon the eccentric sleeve in an axial direction.

Abstract: A piston for a hydraulic motor including a body having a guiding and sealing surface, a base, and a top, which top is providing with a cradle-shaped recess. The base is provided with an additional cradle-shaped recess whose concave surface faces in the direction in which the concave surface of the recess in the top faces.

Abstract: A spindle body defining a central axis and having a hydraulic motor assembly operably mounted thereon. At least a portion of the hydraulic motor assembly is rotatable relative to the spindle body about the central axis. A plurality of hydraulic passages extend within the spindle body. Each of the passages includes axial and lateral sections. The axial sections are in fluid communication with the hydraulic motor assembly and define a first centerline extending substantially parallel with the central axis. Each of the lateral sections are in fluid communication with one of the axial sections and form a port on an outer surface of the spindle body. The lateral sections also each define a second centerline wherein the second centerlines are positioned in mutually parallel planes and each of the first centerlines and the central axis are substantially parallel with each of the mutually parallel planes. A method of manufacture is also disclosed.

Abstract: The invention relates to a hydraulic group comprising a reservoir (28) for oil, in which a multiple piston pump (60) is arranged. The individual pumps (61) are cyclically driven by an eccentric ring (29). In order to ensure a permanent immersion of the individual pumps in the reservoir (28), an auxiliary reservoir (47) providing oil for refilling the reservoir (28) is arranged above the reservoir. The auxiliary reservoir (47) is connected to an additional tank (45) by means of a connection line (48).

Abstract: A fuel pump for use in an internal combustion engine, the fuel pump comprising a pumping plunger for pressurising fuel within a pump chamber during a plunger pumping stroke, a rider member co-operable with a drive, and an interface member, for example a foot of the plunger or an intermediate tappet, for imparting drive from the rider member to the pumping plunger to perform the plunger pumping stroke. The interface member comprises an arcuate contact surface co-operable with the rider member. The inventive concept also extends to a pumping plunger for pressurising fuel within a pump chamber of a fuel pump, the pumping plunger comprising a foot having an arcuate contact surface for engaging a rider member of a fuel pump in use.

Abstract: A hydraulic machine arrangement includes at least one hydraulic machine having a plurality of pistons reciprocating within corresponding cylinders. The pistons can be driven by a cam to operate the hydraulic machine as a pump, and they can drive the cam to operate the hydraulic machine as a motor. The hydraulic machine can be configured to selectively disengage a certain piston or pistons from the cam to operate at less than full displacement. Controlling the pressure in the cylinders corresponding to the disengaged pistons can be accomplished by a number of mechanisms, including selectively exhausting fluid from the cylinders, or using a jet pump to siphon off some of the fluid from a high pressure side of the hydraulic machine. Two of the hydraulic machines can be mounted together to help balance axial forces and eliminate the need for an expensive high capacity thrust bearing.

Abstract: There is disclosed a radial piston machine comprising a cylinder block having at least one bore in which a piston supported on an eccentric disk is movably guided via roll bodies, wherein at least one hydrostatic relieving field is provided between the piston and the roll body. According to the invention, the active surface A2 of the relieving field is equal to or larger than the active piston area A1 of the piston restricting a cylinder chamber and the relieving field is in fluid communication with the cylinder chamber via a hydraulic resistance.

Abstract: A housing has a cylinder and a compression chamber. A plunger is slidable in the cylinder and configured to pressurize fuel in the compression chamber. A cam is eccentric with respect to a shaft center axis of a camshaft and integrally rotatable with the camshaft. A sliding member is slidable around an outer circumferential periphery of the cam and configured to revolve around the shaft center axis in conjunction with rotation of the camshaft. The plunger is slidable on the sliding member and configured to convert the revolution into a linear movement. The cam and the sliding member are accommodated in the housing. The sliding member has an opening through which the outer circumferential periphery is partially exposed.

Abstract: A hydraulic mechanism including a cylinder block having radial pistons and mounted to rotate in a stationary casing, and a distribution cover that forms a portion of the casing that has feed and discharge ducts that extend between an outside face and inside of face of the cover. The internal distributor has distribution ducts that are selectively connected to the feed and discharge ducts that open out into a distribution face that is perpendicular to the axis of rotation and that is disposed against the communication face of the cylinder block so as to cause the distribution ducts to communicate with the cylinder ducts. In a zone defined radially outwards by end-wall portions of the cylinders, a transverse face of the cylinder block is provided with an axial setback in which at least a portion of the distributor is disposed.

Abstract: The invention relates to a wind energy system with hydraulic energy transmission with non-symmetric actuation. The non-symmetric actuation is caused by valve control and mechanical means for controlling the actuation of the pistons. A cylinder unit is provided comprising a drive unit and an output unit associated with two hydraulic connections. The drive and the output unit comprise a minimum of two cylinders, in which pistons are reciprocating. Some of the cylinders can be switched off during low wind speeds. The cylinders communicate with a low pressure manifold and a high pressure manifold. These manifolds are part of the hydraulic connections. Use of the fluid-working machine as transmission in wind energy systems increases the overall economical efficiency.

Abstract: In an engine having a crankshaft driven by reciprocating pistons in an arrangement of cylinders, a spider bearing is fixed to a crankshaft journal that is offset from the central axis of the crankshaft. Each piston is drivingly linked to the spider bearing by a connecting rod. Circular links at the opposite ends of each connecting rod are fitted with an inner bearing ring to provide low friction movement of the ends of each connecting rod relative to the piston and the spider bearing. Hubs equally spaced about the central axis of the spider bearing enable connection of the rod links to the spider bearing. In a preferred embodiment, the spider bearing is formed of a bearing material that surrounds the outer surface of the connecting rod links which, combined with the inner bearing rings, provides a double-backed bearing for carrying the piston load.

Abstract: A portable, refrigerant recovery unit for transferring refrigerant from a refrigeration system to a storage tank. The recovery unit includes two, opposed piston heads rigidly attached to respective piston rods that extend along a common fixed axis. The piston rods are rigidly attached to the yoke member of a scotch yoke arrangement. In operation, incoming refrigerant from the system is simultaneously and continuously directed to the opposing piston heads wherein the forces of the pressurized refrigerant on them counterbalance or neutralize one another. The scotch yoke arrangement includes a two-piece slide mechanism mounted about a cylindrical crank pin and a single piston embodiment is additionally disclosed.

Abstract: In an electrically-driven piston pump including a fluid reservoir for retaining fluid that has leaked into a cam chamber, at an edge between a side wall surface of the cam chamber and the fluid reservoir, an upper edge, which is positioned on the upper side, is arranged so as to extend downward from the electric motor side toward the side away from the electric motor. With this arrangement, the fluid that has leaked into the cam chamber from a piston bore flows from the electric motor side toward the side away from the electric motor, coursing along the upper edge due to the gravity, and is thus introduced into the fluid reservoir.

Abstract: A primary scotch yoke and a secondary scotch yoke are coupled in opposing arrangement and rigidly attached to a linearly reciprocating element. Each scotch yoke includes a rotary actuator with a cam follower and a yoke attached to the reciprocating element. Each yoke has a cam with an open gap through which the follower may be disengaged from the cam and stopped to an idle position. The follower of the secondary scotch yoke is kept idle in a position similarly disengaged from its cam. A controller detects a failure in the primary scotch yoke, disengages the cam follower of the primary yoke from its cam, and energizes the secondary scotch yoke, thereby causing its cam follower to engage its yoke and continue to provide uninterrupted motion to the reciprocating element, in particular the portable pneumatic pump driving an artificial heart.

Abstract: A multipiston pump including a plurality of piston pumps hydraulically combined into at least two pump units are coupled on the intake side, but supply two separate hydraulic circuits of a vehicle brake system with pressure fluid. To reduce brake pedal pulsation the piston pumps are driven in phase-offset fashion. An eccentric unit comprising two spaced-apart cams rotated counter to one another, with the individual piston pumps being located in a number of sectional planes through the pump housing corresponding to the number of cams and locate the connecting conduits for hydraulically coupling the pump units are located in a region of the pump housing defined by the sectional planes.

Abstract: A radial piston pump has a pump housing (1) and at least one pump unit (2) with a pump piston (3) and a cylinder (4) wherein the pump piston (3) can be mounted such that it can be moved backwards and forth, wherein the pump unit (2) can be driven by means of a camshaft (5) mounted in the pump housing (1); and a roller plunger (6) is arranged between the camshaft (5) and the pump unit (2), consisting of a plunger (7) and a roller (8), wherein the plunger has a guide area (9) which is used to guide it a first slot-shaped guide groove (10) of the cylinder insert (4). The roller plunger (6) is thus reliably prevented from rotating inside the cylinder insert (4). The radial piston pumps are particularly suited for high rotational speeds occurring in high-pressure fuel pumps.

Abstract: The invention relates to a drive device for a piston pump of a braking system of a vehicle having at least one piston element displaced in the longitudinal direction in a housing between an upper dead center and a lower dead center by means of an eccentric device. The eccentric device comprises at least one cam-shaped eccentric element having a covering surface forming a control curve which is used to control the displacement of the piston element. A roller bearing device is arranged between the control curve of the eccentric element and the piston element, which has such an elasticity that the piston element can be controlled according the predefined contour of the control curve of the eccentric element.

Abstract: A hydraulic machine which can exchange hydraulic fluid pressure with rotational motion of an input/output means, having a radial arrangement of a plurality of hydraulic piston and cylinder assemblies about a crankshaft, the hydraulic cylinder and piston assemblies being longitudinally spaced along the crankshaft; and a means for varying eccentricity of the crankshaft whereby reciprocal motion of the pistons within the respective hydraulic cylinders is consequential to rotational motion of the crankshaft about the longitudinal axis of the crankshaft.

Abstract: A rotary displacement machine with radial pistons, comprising a supporting structure, with a main body and a cover, a centrally mounted distributor, a rotating unit consisting of a rotor provided with a number of radially extending cylindrical chambers, each chamber containing a respective piston mounted for sliding movement in a first direction along a first axis coaxial with the longitudinal centerline of the respective cylindrical chamber; wherein the rotor is mounted by support bearings means in the main body and cover and the distributor is mounted to float within a space defined by the cover and with coaxial relationship in the rotor by bearing means.

Abstract: A housing has a cylinder and a compression chamber. A plunger is slidable in the cylinder and configured to pressurize fuel in the compression chamber. A cam is eccentric with respect to a shaft center axis of a camshaft and integrally rotatable with the camshaft. A sliding member is slidable around an outer circumferential periphery of the cam and configured to revolve around the shaft center axis in conjunction with rotation of the camshaft. The plunger is slidable on the sliding member and configured to convert the revolution into a linear movement. The cam and the sliding member are accommodated in the housing. The sliding member has an opening through which the outer circumferential periphery is partially exposed.

Abstract: A high precision hydraulic synchronous and proportional flow dividing and flow collecting apparatus comprises two hydraulic motors having the same displacement and their crankshafts be connected into one crankshaft. The two hydraulic motors have a common oil inlet port, and have an individual oil exhaust port respectively. In the casing of the two hydraulic motors a plunger cylinder and a plunger piston that is matched with the plunger cylinder are provided. Between the plunger cylinder and the plunger piston an automatic compensating combined sealing unit is provided. Between the plunger piston and the linking rod lubrication damping holes are eliminated. Thereby, the leakage amount is further reduced. The advantage of the present invention are that it has the synchronous control function; the synchronous precision comes up to ±02%; it is of simple structure, high efficiency, energy saving, low cost, smooth operation noise, reliable performance and convenience in maintenance.

Abstract: Proposed is a radial piston pump with a pump body, in which pistons and cylinders are circumferentially arranged about a driven eccentric, which the pump possesses a faceted slip ring (9) assembly which has an inner diameter and a polygonal outer diameter, the polygon consists of straight, axial parallel surfaces (13), the number of which represents the number of pistons (2) contained in the radial piston pump.

Abstract: What is disclosed is an axial-piston machine having at least one swash plate and one cylinder drum supported thereon, which includes a multiplicity of cylinder sleeves. To the cylinder sleeves a row of pistons is associated which is connected with a shaft. In accordance with the invention, the cylinder sleeves are articulatedly mounted in the cylinder drum.

Abstract: A scotch yoke type fluid device in which the pistons are decoupled from each other is provided. Each piston of the device has its own pair of sliding surfaces and its own slider. The sliding surface of each piston is disposed on the same side of a big end bearing of a crank. The main axis of the crank is movable along a path such that the pistons are neither substantially retarded nor advanced. The effective centre of mass of the crank, piston and slider remains stationary relative to the crank axis. Each piston includes a guide for constraining the piston to move along the piston axis. An intermediate member may interconnect the piston and the slides.

Abstract: Drive mechanism having stroke member (HG) fixed to shaft (W) of a mechanism having eccentric bearing (HL) which connects stroke member (HG) to coupling member (KG) connected by transverse bearing (QL) to pressure member (DG). Included is pressure source (DQ) for fluid lubricant connected to transverse bearing (QL). This connection includes first passage (K1) extending through stroke member (HG) into eccentric bearing (HL) and second passage (K2) extending from eccentric bearing through coupling member (KG) into transverse bearing (QL). A space arrangement provides for conduction of the fluid lubricant to second passage (K2), this space arrangement having an arrangement permitting a flow of the fluid lubricant between first and second passages The applications has been limited to unidirectional pumps. (K1,K2) only within low pressure phases of the fluid lubricant.

Abstract: A radial piston pump for generation of high fuel pressures in fuel injection systems comprises a pump housing, a pump shaft and at least one cylinder insert, arranged radially to the pump shaft. A cylinder chamber is located within the cylinder insert in which a piston can move back and forth. The cylinder insert is connected with a front face to a flattening of the pump housing, by connecting means. The cylinder insert comprises an inlet port and a high pressure port. The front face of the cylinder insert and/or the flattening of the pump housing comprise precisely machined raised sealing regions for sealing the cylinder insert against the pump housing, which are relatively small in relation to the total front face of the cylinder insert and the total flattening of the pump housing. A high surface pressure is thus achieved in the sealing region.

Abstract: A pump element and a piston pump for generating high fuel pressure are proposed, in which tilting of the piston base relative to a drive shaft is effectively suppressed, so that the service life of the high-pressure fuel pump is increased.

Abstract: A roller bearing including a plurality of rollers which are provided between an outer circumferential surface of an inner member and an inner circumferential surface of an outer member; and a substantially cylindrical roller holder which has a plurality of pockets holding the plurality of rollers, respectively, such that each of the rollers is rotatable about an axis line thereof and which is rotatable around the inner member. A sign of a skew angle of each of the rollers is constant irrespective of how much the each roller is inclined relative to a corresponding one of the pockets in a circumferential direction of the roller holder.

Abstract: The invention concerns a hydraulic device with a housing and a rotor which can rotate in the housing and has fixedly mounted pistons. Around the piston there are drum sleeves which each, together with a piston, form a chamber of variable volume and which are supported by a drum plate with an axis which intersects the axis of the rotor at an angle. Clamping means hold the drum sleeve against the drum plate and the clamping means are designed in such a manner that the drum sleeves can make a movement along the drum plate which is double of the radial movement which occurs in the event of synchronous rotation between the drum plate and a drum sleeve.

Abstract: A rotary displacement machine (10) with radial pistons (19), includes a bearing (29) having a rotating thrust ring (28) and a stationary outer ring (30), with bearing rollers (31) therebetween. The thrust ring (28) includes one engagement device (43, 45) per piston (19), the engagement device (43, 45) allowing movement in a straight line along a second direction defined by a second axis (b) perpendicular to a first longitudinal centerline (a) of the piston (19).