Abstract: High pressure pump systems with reduced pressure ripple for use with waterjet systems and other systems are described herein. A pump system configured in accordance with a particular embodiment includes four reciprocating members operably coupled to a crankshaft at 90 degree phase angles. The reciprocating members can include plungers operably disposed in corresponding cylinders and configured to compress fluid (e.g., water) in the cylinders to pressures suitable for waterjet processing, such as pressures exceeding 30,000 psi.

Abstract: One or more examples of the gas boosters described herein aim to provide a light weight gas booster configured to produce high output pressure levels at high volumes. Generally described, one or more examples of the gas boosters reduce the dead volume in a piston assembly, thereby increasing the ratio of the output pressure to the input pressure. In that regard, several examples of the gas boosters disclosed herein have a first check valve as a disk-type check valve or the like and a second check valve as a ball-type check valve or the like. Furthermore, one or more examples include an inwardly acting cam configured to convert rotary motion to reciprocating motion by an inner surface thereof.

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 variable displacement hydraulic/pump motor has a yoke with a pair of shafts aligned to define a yoke pivot axis and connected to a valve plate therebetween having intake and discharge apertures. A rotatable cylinder barrel has piston cylinders open at one end to receive a piston head and opening through fluid ports at another end, flush against the valve plate surface. A drive block is mounted on an input/output shaft for rotation about a central axis of rotation inclined at an angle relative to the longitudinal axis of the cylinder barrel which may be changed by a drive engaging the yoke at a point near its pivot axis. Loads on bushings supporting the yoke shafts are reduced by providing radially extending fluid ports in the shafts and in communication with the intake and discharge apertures of the valve plate.

Abstract: A variable displacement hydraulic/pump motor has a yoke with a pair of shafts aligned to define a yoke pivot axis and connected to a valve plate therebetween having intake and discharge apertures. A rotatable cylinder barrel has piston cylinders open at one end to receive a piston head and opening through fluid ports at another end, flush against the valve plate surface. A drive block is mounted on an input/output shaft for rotation about a central axis of rotation inclined at an angle relative to the longitudinal axis of the cylinder barrel which may be changed by a drive engaging the yoke at a point near its pivot axis. Loads on bushings supporting the yoke shafts are reduced by providing radially extending fluid ports in the shafts and in communication with the intake and discharge apertures of the valve plate.

Abstract: Engineered surface treatments are applied to different types of hydraulic motors and pumps to improve the life of the contacting surfaces in said motors and pumps. The engineered surface treatments are selected from texture modifications and tribiological coatings and selectively applied to one or both of the contacting surfaces to reduce friction and improve fatigue life under poor lubrication operating conditions.

Abstract: The invention refers to a piston assembly for a radial piston hydraulic motor. The essence of the solution lies in that a longitudinal axis (12) of a roller (11) substantially coincides with an axis through centre of gravity of a piston body (2). The roller is placed in a bed (10) of a bearing bush (6) which is located inside the piston (1) in a manner that the edges thereof slip through grooves (14) in the lower inner portion of the piston (1). The roller (1) being inserted this way is afterwards rotated in a certain angle, together with the bearing bush (6), thus, preventing the roller (11) from falling out of the piston (1).

Abstract: A piston assembly of a hydraulic radial piston-type machine, an essential characteristic thereof being the arrangement of a roller element in a piston head. The portion of contact surface of the roller element lying close to a crown of the piston is always arranged in the area between the piston crown and a step extending radially inwards and dividing the head of the piston from the guide portion.

Abstract: A positive displacement rotary machine includes a piston rotor rotatable about a first axis and including a number of pistons equally spaced about the first axis and rotatably mounted about their axes on the piston rotor; a chamber rotor rotatable about a second axis spaced from the first axis, including a central common chamber and a number of radial fluid chambers arranged in diametrically opposed pairs across the common chamber, and guide tracks extending between opposing pairs of radial chambers across the common chamber for kinematically constraining each of the pistons as they move from one of their associated radial chambers to the other through the common chamber, and intake and exhaust ports for introducing and exhausting fluid from the radial chambers.

Abstract: The eccentric end portion (5) of a pump shaft (3) is mounted in a needle roller bearing (6) which comprises a sheet metal bushing (9) and needle rollers (7) guided in a cage (8), wherein the end of the sheet metal bushing (9) remote from the pump shaft (3) is provided with a closed bottom (18) to prevent a displacement of the sheet metal bushing (9) in axial direction.

Abstract: The present invention relates to a piston intended for a hydraulic radial piston motor and being of the type comprising an outer cam ring having an undulated inner cam surface, an inner cylinder block which is rotatable relative to the cam ring and has radially outwardly directed cylinders, a plurality of such pistons which move in said cylinders and cam rolls which rollingly run against the cam surface and are slidingly arranged against the respective pistons. The piston has an essentially cylindrical circumferential surface, an inner end surface and an opposite outer end surface, which is adapted to be slidingly arranged against the cam roll and therefore is formed with a groove-like recess, which in cross-section is essentially part-cylindrical, and with two lateral portions which extend around and partly surround the circumferential surface of the cam roll and via which reaction forces in the tangential direction of the cylinder block are transmitted between the cam roll and the cylinder block.

Abstract: A hydraulic motor with propulsion members located between an eccentric cam associated with a shaft and a counter-element. The propulsion members consist of two elements slidable telescopically with respect to one another in the longitudinal direction and having annular bearing shoulders kept pressed against corresponding sliding-contact surfaces of the eccentric cam and the counter-element by springs. The resilient springs are located outside the propulsion members and are arranged between the annular edges and elements for mechanically retaining them.

Abstract: A pump for conveying a medium, especially a gas-liquid mixture, with a housing, an annular surface extending inside the housing, an eccentric arranged off center in relation to the annular surface and at least one displacer arranged between the annular surface and the eccentric. The displacer is held in position in relation to the annular surface and the annular surface can rotate in relation to the eccentric. A hollow shaft delivers mixture to the eccentric which has connections to the displacer for delivering mixture to and receiving it from the displacer.

Abstract: An adjustable radial piston machine (pump or motor) is described whose drive mechanism (10) has a comparatively compact structure and an especially good mechanical efficiency. The drive mechanism (10) has a bearing ring (19) which is arranged concentric to a rotor (11) and which can be swung or pivoted about a symmetry axis (Q,H) different from its rotation axis for adjustment of the radial piston machine. An adjusting device (22) for pivoting the bearing ring extends axially parallel to the bearing ring (19) and acts on a facing surface of the bearing ring (19). Working pistons (13) guided in the cylinders in the rotor perform two motion cycles per revolution of the rotor, which are equal, but in opposite directions, over respective 180.degree. angular intervals. Cylinders (12) on opposite sides of the rotor are acted on by identical pressures so that the forces on the rotor are balanced and the rotor rotates largely free of friction.

Abstract: Disclosed is a self-sealing valve and cylinder configuration, an internal combustion rotary engine, or pump or compressor, with a rotating central housing which includes at least one cylinder aperture, a non-rotating timing pulley mount concentrically positioned within the central housing, a crank shaft eccentrically mounted within the central housing, a valve housing attached to the central housing and which retains a cylinder between it and the central housing, a piston within each cylinder, the piston rod is eccentrically mounted to the crank shaft, and a rotating valve within each valve housing.

Abstract: A hydrostatic radial piston engine with two rotors that are supported on an axle so that they can rotate easily thereon. The rotors have a plurality of radial bores with displacement elements (pistons with slide ring) therein, sliding on the inside of a piston ring. The bores are connected via control slits with transport channels (high-pressure/low-pressure) that open on a side on the rotors for the purpose of controlling the transport of the pressure medium. The two rotors can be rotated easily on the axle which mounted on an intermediate bottom. The intermediate bottom is disposed between the rotors. Check plates are disposed on the ends of the axle which take up the axial forces produced by the pressure medium in the control slits of the rotors. The piston rings are supported in the intermediate bottom by a common connecting shaft.

Abstract: A slipper guide for use in radial piston type hydraulic pumps and motors, especially those utilized in hydrostatic transmissions. The slipper guide provides an annular path for the slippers, guiding and maintaining the slippers engaged with the inner circumferential surface of the track ring as the slippers are rotated within the track ring by the cylinder. The slipper guide consists of two plates axially attached to the track ring and fixed relative thereto. Each plate includes an annular, axially inwardly extending projection forming an annular surface upon which an under surface of an outer portion of the slippers rests. The annular projection positions and maintains the top surface of the slippers against the inner circumferential surface of the track ring.

Abstract: A motor or pump assembly (1) comprises a cylinder block (4) with a plurality of radially positioned cylinders (3), a piston (2) arranged slidably reciprocable in each of the cylinders, a cam ring (7) cooperating with the pistons and being rotatably journalled on the cylinder block, and a distributor valve (9) arranged centrally in the cylinder block to control a flow of fluid to and from the cylinders in operation. The cam ring (7) is journalled on the cylinder block (4) with at least one ball bearing with balls (25) arranged on each side of the cylinder block. These balls run in grooves which are positioned close to the sides and periphery of the disc-shaped cylinder block. This provides a structure which has a very small axial length and which is simultaneously capable of absorbing great loads both radially and laterally.

Abstract: A pump with axial thrust compensation having an external housing, a main shaft within the housing to which are axially fixed two spaced apart rotors. The main shaft supports the rotors apart at respective collars against which the rotors are clamped. Each rotor including a series of radially displaceable elements within respective bores. The stroke rings for the rotors are rigidly attached to each other by a respective bearing shaft. A respective stroke ring around each rotor for moving the displaceable elements into and out of the bores. A respective control slot into each of the bores in the rotor and the control slots of each rotor extending laterally toward the other rotor.

Abstract: The ease of assembly of a radial plunger pump is improved while preventing an external leakage of liquid. A pump housing 2 in the form of a cylinder having a closed bottom contains a pintle 4 therein, which is secured to the bottom of the pump housing 2 by a bolt 6. A rotor 8 is rotatably fitted around the pintle. The rotor is formed with a plurality of radially extending cylinder bores 8a, in each of which a plunger 10 is slidably disposed. A guide ring 16 is disposed around the rotor. A motor 20 is fastened to and secured to the opening of the pump housing, and includes a drive shaft which is connected to the rotor to drive it for rotation. By allowing parts to be assembled into the pump housing in one direction, the ease of assembly is improved while preventing a liquid leakage.

Abstract: A hydraulic power system having first and second hydraulic power converters in which the speed of the second power converter is proportional to the speed of the first power converter. The first hydraulic power converter includes a plurality of hydraulic power producing elements. At least one of the power producing elements provides power for power driving, and at least one of the power producing elements pumps hydraulic fluid. The hydraulic fluid is connected to and drives the second hydraulic power converter at a speed proportional to the speed of the first power converter.

Abstract: A fluid pressure independent, mechanically controlled dampener for a hydrostatic transmission pump track ring is shown. In one embodiment, two opposing wedge-shaped blocks are biased against each other by a spring-loaded bolt. A pad, axially adjacent the track ring on one side and axially adjacent and held together with one block by a Z-bracket on the other side, is biased against the track ring by pressure exerted through the spring-loaded bolt and wedging action of the opposing wedges. In another embodiment, a spring-loaded piston disposed within a spring housing, exerts pressure against a first pad axially adjacent the track ring to hold the track ring against another pad axially adjacent and opposite the first pad.

Abstract: The improved hydrodynamic variator of velocity comprises a pump (3) having radial pistons and a hydromotor (4) also having radial pistons. At least the pump is arranged with a variable eccentricity and there is provided a central body (56) the latter having frontal distributors (30 and 31) which are placed in communication with the radial cylindrical cavities respectively of the pump and the hydromotor by means of the openings of the conduits (32 and 33). By varying the eccentricity of the pump, the rate of flow of the liquid in the pump is varied, thus causing a variation in the number of turns of the hydromotor.

Abstract: In a radial piston engine having pistons bearing against the circumference of an eccentric, which pistons execute a swivelling motion upon the rotational motion of the eccentric and are in engagement with a guide body, which bears on the radially outer end by a radially outwardly convex spherical-annular bearing face against a concave spherical-annular bearing face in the housing or cylinder cover. To attain complete piston relief, the bearing arrangement is designed such that the guide body (2) is provided with an upper end face (8) which is acted on by the pressure medium over a hydraulically effective plane (de) extending perpendicularly to the longitudinal axis of the guide body (2). The hydraulically effective plane lies in the area of the bearing face (5) on the housing (6) or intersects the face for all swivelling positions of the piston (3).

Abstract: This invention relates to a hydraulic mechanism comprising a cam; a cylinder-block mounted to rotate with respect to the cam; a plurality of cylinders arranged in this cylinder-block; a plurality of pistons mounted to slide inside a cylinder; a plurality of rollers for abutment of the pistons on the cam, each roller being mounted on a piston, rotating by means of a bearing for rotation, being axially defined by two transverse faces, and being capable of penetrating, at least partially, inside the cylinder in which this piston slides, the end of the piston comprising two recesses corresponding at least to the intersection of the cylindrical surfaces of the roller and of the piston, being open in the upper part of the piston; and two wedging pieces which are each disposed in a recess between the roller and the cylinder, in order to ensure axial wedging of the roller parallel to its axis of rotation.

Abstract: The present invention is an expander band for use in hydraulic pumps, motors, and hydrostatic transmissions. The band has a plurality of elongated slots located circumferentially which receive slippers attached to pistons. One reduced dimension slot fixes the position of a slipper relative to the expander band while the other slippers move within the elongated slots. The fixed slipper limits the range of movement of the other slippers relative to the band, and thus the slippers avoid abutting the side ends of the elongated slots.

Abstract: A fluid motor which is useful as a pump or as an hydraulic or pneumatic engine with a high torque low speed output. The fluid motor (10) comprises at least one drive disc (24) having a generally curved outer surface (42), at least one reciprocably mounted piston (26), the outer curved surface of the drive disc (24) being formed of alternating crests (44) and valleys (46) and there being provided a plurality of rollers (48) which are arranged to engage with the curved surface (42) of the drive disc (24), the number of rollers (48) and the number of crests (44) being different by at least one. Feeding fluid to the piston (26) causes the piston (26) to reciprocate so that the disc (24) is caused to undergo orbital movement and the housing (12) is thus caused to rotate.

Abstract: A member oscillates on a face and another member pivots on a bed of the first member. Passages are provided through the members to lead a lubrication fluid under pressure into a fluid pocket between the mentioned face and one of the members. The fluid pressure in the pocket carries a major portion of the load of one of the members on the face. The oscillation of the members has one stroke under higher load and one under less load. The pivotal movement of the other member controls the flow of fluid through the passages to provide high pressure in the fluid pocket at the stroke under higher load and lower pressure in the pocket at the stroke under less load. The arrangement is especially suitable to be provided on pistons and piston shoes of radial piston machines. But it can also serve to carry load on other members of machines or vehicles, wherein at least two movements are taking place and a source of supply of fluid under pressure is available.

Abstract: A fluid energy converter having a cover to support a cylinder barrel positioned and mounted on the casing main body. At the opening end of the casing main body, a helical taper plane at an angle not more than 45.degree. with respect to the axial centerline of the body open end is formed, helically of the casing body. The taper plane faces the open end of the casing main body and a taper plane at the same angle is formed on the cover. The cover is fitted to the casing main body by threading together the taper planes so that the cover is correctly positioned by the taper guide action. Because the angle of taper plane is not more than 45.degree., the cover and casing main body are not dislocated if a force is applied in a radial direction.

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.

Abstract: A radial plunger pump is provided which includes a motor housing having a motor mounted therein. A pump housing is further provided and has a pump portion defined therein. A shaft is mounted between the motor and the pump portion so that the pump portion operates when rotation of the motor is transmitted to the pump portion by rotation of the shaft. A constant pressure chamber is defined between a first seal member and a second seal member both of which are fixed to the pump housing. The leakage of oil from the pump housing toward the motor housing is prevented by the first and second seal members and the constant pressure chamber. Further, a plate is provided within the constant pressure chamber which rotates with the shaft and prevents the entry of foreign objects into the constant pressure chamber through a constant pressure port which communicates to the ambient atmosphere.

Abstract: A radial-piston machine has a rotor formed with a plurality of cylinders, wherein pistons are reciprocable. Each such piston is formed on its radially outer end with a reception seat and a pivotable portion of a respective piston shoe is engageable on the seat. The piston shoes ride on an eccentric cam in a housing of the machine. Each such piston shoe may move radially into and out of engagement with the respective piston. A pair of end members axially flank the piston shoes to prevent their escape in axial direction. The former requirement to connect the piston shoes pivotably to the pistons is eliminated by the application of seal- and support-faces in the rotor, a stroke guide face on the cam, outer faces and end faces on the piston shoes and innermost faces on provided end members, whereby the piston shoes are retained between the mentioned faces, but permitted to otherwise free movement between the pistons, rotor, end members, and the cam.

Abstract: In a radial piston machine which includes a driven rotatable rotor with radial pistons displaceable in radial recesses of the rotor by pressure medium and carrying rollers which cooperate with a cam track of the rigid cam plate, the length of the rollers can be increased due to the provision in the bores receiving the rollers respective opposing recesses in which portions of the roller are received.

Abstract: In a fluid pump or motor improvements are provided to the piston shoes therein to permit a higher pressure in the respective device. Other improvements are done to the hydrostatic bearings in radial piston or radial chamber type fluid motors and pumps. A further arrangement is, that plural pistons are applied to permit the use of two different fluids in the respective device. This leads also to the application of disc springs and their modification in a pump or motor to make the pumping of non-viscous fluids like water possible at very high pressure. Motors are provided with arrangements to permit them to drive and to carry simultaneously or to have hollow shafts, whereby improved and novel machines and vehicles are obtained.

Abstract: A bush assembly is inserted into the rotor hub around a cylindrical control body which is partially extending into the bush to fill the interior of the bush. In such device, where fluid flows through the control body and the working chambers in the rotor of the machine, leakage escaped through the clearance between the control body and the rotor. Due to the novel bush assembly the respective high pressure is led through passages which extend half way around the bush into recesses diametrically located in the bush. There the pressure is utilized to press respective seal-portions towards the control body to at least partially seal the escape of leakage, while maintaining a radial pressure balance between the control body and the bush.

Abstract: In a radial piston pump, motor, transmission the deep diving or entering piston shoe is utilized and swingably borne in the pivot-bed of the radially reciprocating piston. Since deep diving piston shoes have large piston strokes, the shoes pivot in the pistons in large angles. Thereby a considerable force - portion of the load on the piston is transferred to the wall between the piston and the cylinder, whereby heretofore short pistons occasionally produced welding and sticking between the cylinder wall and the piston wall. The piston therefore receives radially extending portions, which may extend beyond the medial portion of the piston shoe and may even enter into the ring groove of the piston stroke actuator ring. Thereby a very long guidance of the piston on cylinder wall portions is obtained, which makes the application of effective pressure balancing pockets at correct location between piston wall and cylinder wall possible.

Abstract: This invention relates to a hydraulic mechanism having a cylinder block comprising cylinders, pistons mounted in these cylinders, and supporting rollers for abutment on a cam with respect to which the cylinder block is mounted to rotate. The mechanism for holding each roller in position with respect to a corresponding piston comprises two distinct supports which each abut on the inner surface of the cylinder, are maintained in position along the axis of the piston, have their angular orientation with respect to this axis constant and possess a face for abutment against an end face of the roller. One application of the invention is the manufacture of a compact engine.

Abstract: A radial piston machine includes a stationary cam plate and a rotational cylinder block provided with radial bores receiving a plurality of radial pistons displaceable in those bores and supported against the cam plate surrounding the cylindrical block by rollers. Each piston has in the region of supporting the roller a web which is cured and supported in one of the grooves formed in the cam plate.

Abstract: In a pivot bar portion of a piston shoe in a radial piston device wherein the pivot portion is pivotably borne in a bed in the piston which extends normal to the longitudinal axis of the piston, recesses are provided parallel to the pivot axis whereby bearing lands are formed between the recesses. The bearing lands are tracting fluid out of the recesses along themselves and the bearing bed face of the piston, when the shoes pivot in the piston. A perfectly operational forced lubrication between the pivot portion and the piston is thereby assured which results in a long life and very high bearing capacity between the piston and the piston shoe.

Abstract: In radial piston pumps and motors the dimensions of the rotor, pistons and piston shoes are optimized for best efficiency and power in a given size and weight. The efficiency and reliability of the piston shoes is improved by the provision of fluid pressure pockets in the outer face of the piston shoe which have cross-sectional areas exceeding the cross-sectional area of the piston whereon the piston shoe is pivotably borne. Welding of the outer face of the piston shoe is prevented and the devices are able to operate with higher pressures and rotary velocities.

Abstract: A hydrostatic piston machine has a housing, a rotor, a plurality of pistons rotatable with the rotor, and a displacing element operative for effecting reciprocation of the pistons and having a surface which is in sliding contact with the latter. Means is provided for reducing friction between the surface of the displacing element and the pistons during the sliding contact. This means includes a recess formed in the surface of the displacing element and communicating with a space which is under pressure so that a cushion of pressure fluid develops between the surface and the piston. The space under pressure may be constituted by a low pressure zone of the machine or by the low pressure and a high pressure zone of the machine.

Abstract: A bush assembly is inserted into the rotor hub around a cylindrical control body which is partially extending into the bush to fill the interior of the bush. In such devices, where fluid flows through the control body and the working chambers in the rotor of the machine, leakage escaped through the clearance between the control body and the rotor. Due to the novel bush assembly the respective high pressure is led through passages which extend half way around the bush into recesses diametrically located in the bush. There the pressure is utilized to press respective seal-portions towards the control body to at least partially seal the escape of leakage, while maintaining a radial pressure balance between the control body and the bush.

Abstract: The invention relates to a hydraulic engine with radial pistons, comprising girders which transmit the thrusts of the pistons and rest against strips secured to the cylinder block.The surface of the cylinder block has a degree of roughness at least equal to the following values given in reference to the currently applied norms 0.25 .mu.RA; 15 .mu.Rt; and 8 .mu.Rp.The invention finds its application in the production of a reliable engine.

Abstract: The invention relates to an engine with radial pistons 9, which are coupled to elastic return means 25 for free-wheeling operation.Said elastic means are constituted by springs 25 whose number is equal to that of the pistons and by levers 21 mounted to pivot, each with respect to a piston 9, about an axis parallel to the axis of rotation 6 of the cylinder block 7, and equal in number to the springs, whereas each spring 25 is coupled to two levers 21, each lever constituting the bond for two springs 25.An application is the production of a hydraulic engine which is reliable and of simple design.

Abstract: A hydrostatic transmission having a pump and a motor of the radial piston type with each cylinder slipper bearing rotatably supported by a hybrid or combination hydrostatic and hydrodynamic bearing on an internal bearing. The hydrostatic bearing component has a restricted port connecting hydrostatic pressure fluid from the cylinder to supply a distribution recess in the slipper bearing surface for hydrostatic pressure feed of the fluid film providing hydrostatic balancing pressure gradient between the slipper and internal bearing to balance a high percentage of the hydrostatic pressure load and to meet flow requirements for low speed operation.

Abstract: Piston shoes in radial piston devices of the prior art were provided with balancing fluid pressure pockets of circular configuration or of elongation normal to the movement direction of the piston shoes. Piston shoes had to provide the space for said pockets and thereby extended over the diameter of the piston. That resulted in deformation of the piston shoe and in friction in areas that cannot be lubricated between the piston shoe outer face and the piston actuator guide face. The invention provides a pair of balancing pockets normal to that of the prior art and extended in the movement direction of the piston shoes. Piston shoes are therefore short in the direction of the pivot axis, deformations are prevented and the areas that cannot be lubricated are reduced to a minimum or removed. The piston shoe becomes thereby able to operate under higher pressures, increased relative speeds and with better efficiency at assured perfect lubrication between neighboring faces.

Abstract: A fuel injection pumping apparatus includes a rotary distributor in which is formed a pair of transversely extending bores having their axes intersecting at the axis of rotation of the distributor member and lying in the radial plane passing through the point of intersection. Each bore accommodates a pair of plungers and the plungers of one of said pair define recesses which receive the inner ends of the plungers of the other pair. In this manner the plungers can be moved inwardly a greater extent before collision of the plungers takes place.

Abstract: A fluid transducer including a reciprocatory piston member and a drive mechanism for converting reciprocation of the piston member into rotation of a rotary member coupled to the mechanism, or vice versa. The drive mechanism includes a first elliptical member centrally mounted within said transducer and a second elliptical member rotatably mounted in engagement with said first member and arranged for reciprocation with said piston member. As said piston member reciprocates said second member rotates with respect to said first member to transmit motion between said piston and said rotary member coupled to the drive mechanism.

Abstract: The guide means for reciprocating the pistons of the cylinder block are mounted on rings which have bearing surfaces eccentric to the surface on which the cylinder block rotates. These rings are also of a diameter greater than the diameter of the surface on which the cylinder block rotates by at least twice the eccentricity of the machine.

Abstract: A radial-piston machine has a rotor formed with a plurality of axially extending slots in each of whose bases is formed a piston-carrying radial cylinder. Each such piston is formed on its radially outer end with a part-spherical seat and a part-spherical portion of a respective piston shoe that rides on an eccentric cam in the housing is engageable in each seat. Each such piston shoe can move radially into and out of engagement with the respective piston. A pair of end members axially flank the piston shoes with play so that these shoes may also move axially relative to the rotor. The piston-engaging portions of the shoes are slightly narrower than the respective cross-slots so that angular free play is also present, and these portions are always engaged radially in the slots.