Abstract: The present invention relates to a piston pump, which is in particular appropriate for the pressure fluid delivery in electronically controlled brake systems, including a housing, a suction valve, a pressure valve, and a pump piston that is designed as a stepped piston having a large-diameter portion and a small-diameter portion. According to the present invention, the stepped piston at its large-diameter portion is guided in a pump cartridge. Preferably, the pressure valve is designed additionally at the cartridge in a radial direction relative to the direction of movement of the stepped piston.

Abstract: In a lifter guide of a high pressure supply pump, a flat plate, whose periphery line is provided with a projection and whose the other periphery line circumferentially opposed to the periphery line is provided with a recess, is formed from a metal sheet by stamping. Then, the flat plate is rounded circumferentially so as to cause the periphery line to abut on the other periphery line so that the flat plate is formed in generally cylindrical shape and the projection is fitted to the recess. Subsequently, the periphery line is seamed by staking or welding with the other periphery line to reinforce fitting between the projection and the recess. Thinner wall thickness of the lifter guide can be achieved with a simpler process, compared to that of the conventional lifter guide formed by forging or machining.

Abstract: The invention relates to a piston pump (10) for a hydraulic vehicle brake system that has traction control. The invention proposes embodying the piston pump (10) with a piston ring (24), for instance a PTFE, which ring serves as both a sealing and a guide ring. The invention lessens the effort and expense of assembly as well as the production costs for the piston pump (10). To achieve reliable sealing, the invention proposes embodying the piston ring (24) with an internal cone on its side toward a pump chamber (18), so that during a pumping stroke, the piston ring (24) is subjected to pressure from the pump chamber (18) and is pressed into sealing contact against a pump bore (12).

Abstract: A high pressure pump for decreasing an initial axial force of a clamping bolt and preventing distortion of a sealing surface and a cylinder form. The high pressure pump has an intermediate member including a cylinder body (4). The cylinder body has a pressurizing chamber (14) communicated with a cylinder (4a) accommodating a plunger (12). Fluid in the pressurizing chamber is pressurized by reciprocating the plunger. The intermediate member is arranged between a cover (6) and a flange (8) and clamped by a clamping bolt (40). The clamping bolt has an exposed area (40a) at its axially central area where the entire periphery of the clamping bolt is exposed from the cover and the flange. One or both of the cover and the flange clamp the intermediate member with a flexing elastic force.

Abstract: A pump assembly is provided which comprises a pump housing, an electric motor attached to the pump housing and having a casing and an output shaft that protrudes into the pump housing to drive a pump within the pump housing, the output shaft having at least two supported portions by way of which the output shaft is rotatably supporting on the casing and the housing, respectively, and an elastic device interposed between one of the supported portions and one of the casing and the pump housing for damping radial vibrations of the output shaft.

Abstract: A pump and a pump piston assembly. The pump piston assembly includes a pump piston, a pump check valve, and a spring. The pump piston has a piston bore extending from a first piston end toward a second piston end. The pump check valve is positioned proximate the first piston end. The spring has an attached portion attached to the pump piston proximate the first piston end and has a biasing portion biasing the pump check valve to fluidly block the piston bore. The attached portion of the spring is closer to the second piston end than is the biasing portion of the sprint. The pump includes the pump piston assembly and a pump sleeve, wherein the pump piston is slidably engaged in the sleeve bore of the pump sleeve.

Abstract: The present invention relates to a motor-and-pump assembly including an electric motor and a piston pump, in particular for slip-controlled brake systems of automotive vehicles, wherein pistons of the pump are adapted to be driven by way of an eccentric, and the drive shaft of the electric motor and a support axle of the piston pump are separately designed, and wherein a three-ring bearing furnished with an eccentric intermediate ring is arranged on the support axle. According to the present invention, at least one counterbalance weight is provided in the proximity of the eccentric for the purpose of noise reduction and enhanced truth of running of the assembly.

Abstract: In a fuel injection pump, fuel pressurized by a feed pump is supplied to an accommodation chamber via a communication path having an orifice. An end of the communication chamber on a side of the accommodation chamber is positioned to face an axial end of a minute space between sliding contact portions of a cam and a bush when the cam is at a given angular position. The fuel fed from the feed pump is injected from the end of the communication path axially deep into the minute space between the sliding contact portions so that oil film for lubrication is formed on the sliding contact portions, resulting in suppressing frictional seizure of the sliding contact portions.

Abstract: In a fuel injection pump, fuel discharged from a feed pump assembly is supplied to each pressurizing chamber through a corresponding metering valve. A portion of the fuel is supplied to a receiving chamber, which receives a drive mechanism that drives plungers, through a space defined between a drive shaft and a bush, which supports the drive shaft. A fuel groove is formed in an inner wall of the bush, so that fuel supplied from the feed pump assembly to the receiving chamber through the fuel groove is also supplied to lubricate between an outer wall of the drive shaft and the inner wall of the bush.

Abstract: A high pressure pump for preventing distortion of a sealing surface or a cylinder form. The high pressure pump has an intermediate member including a cylinder body (4) having a pressurizing chamber (14) communicated with a cylinder (4a) accommodating a plunger (12). Fluid in the pressurizing chamber is pressurized by reciprocating the plunger. The intermediate member is arranged between a cover (6) and a flange (8) and is clamped by clamping bolts (40). An electromagnetic spill valve (10) for receiving reaction force from the pressurizing chamber when the fluid in the pressurizing chamber is pressurized is attached to the cover (6) at a position for reducing the clamping force applied to the intermediate member by the clamping bolts.

Abstract: An actuator carrier comprises an aperture being adapted to receive actuator and a bore being adapted to carry high pressure fluid through the carrier. The actuator carrier can be incorporated into a unit pump allowing for a more efficient design and manufacture process, including linear alignment of all of the unit pumps primary components.

Abstract: A piston pump comprises cylinder attached within a cavity of a pump housing. An outlet check valve seat is defined about an outlet of the cylinder. A piston is slidably received in a bore of the cylinder and has a first passageway formed therein. A cylinder head encloses the outlet of the cylinder and defines a second passageway therein. The first passageway has an inlet in fluid communication with the cavity of the pump housing, and an outlet in fluid communication with a pumping chamber defined in the pump housing. A first spring retains the piston to the cylinder. A first check valve member is a ball retained near a valve seat formed in the first passageway of the piston by a disk spring, and allows fluid to flow only from the inlet to the outlet of the piston.

Abstract: In order to provide a method for high volume and high pressure operation of a variable delivery type single cylinder plunger pump, the displacement of the piezoelectric element 20 is magnified by a hydraulic displacement magnifying mechanism comprising a large-diameter bellows 204, a small diameter bellows 202 and working fluid 208, and an engaging member 201 is displaced to control the time interval of opening and closing the intake valve 5. The large-diameter bellows 204 is used at all times in the state compressed in the direction of displacement transfer, thereby ensuring that the pressure of the working fluid 208 is maintained at a positive value to prevent vapor from being generated.

Abstract: A high pressure fuel supply apparatus is constituted by a plunger reciprocating in a sleeve of a high pressure fuel pump so as to form a fuel pressurizing chamber between the plunger and the sleeve, a suction valve provided in a fuel suction port for sucking fuel into the fuel pressurizing chamber, and a discharge valve provided in a fuel discharge port for discharging fuel from the fuel pressurizing chamber into a high pressure fuel discharge passageway communicating with an internal combustion engine, the discharge valve reciprocating axially so as to perform an open/close operation, wherein the high pressure fuel supply apparatus further comprises a holder for regulating an axial reciprocating movement of the discharge valve in the open/close operation within a predetermined range.

Abstract: A tappet turning prevention structure for a fuel supply apparatus includes a piston defining a fuel pressurizing chamber within the housing. A tappet disposed at one end of the piston has accommodated in it a roller driven by a cam of an engine and a roller supporting pin for transmitting a force from the cam to the piston. The tappet is housed by a bracket which has one or two grooves in an inner surface of it for supporting the roller supporting pin at one or both ends. The number of parts can be decreased because the turning prevention pin for the tappet and the roller supporting pin is a single common pin, and therefore the need of controlling of the press-fit loads is eliminated because no process for thrusting the tappet turning prevention pin into the outer circumference of the tappet is involved.

Abstract: The present invention relates to a piston pump, in particular for controllable brake systems such as ABS or ESP, wherein a working chamber (40) of the pump in front of a piston (3, 52) is delimited by a pressure valve, and a resetting spring (4, 51) with its one end is supported on a valve seat carrier (9, 54) of the pressure valve and with its other end resets said piston (3, 52) into its bottom dead center position. An object is to render the assembly of the mass-produced pumps as inexpensive and simple as possible. To achieve this object, the present invention discloses that the resetting spring (4, 51) be adapted to be attached directly or indirectly to the valve seat carrier (9, 54) in addition.

Abstract: A high pressure fuel pump has a plunger that extends through a cylinder and is reciprocally located in a pressurizing chamber. The plunger is reciprocated by a lifter and changes the volume of the pressurizing chamber to pressurize fuel in the pressurizing chamber. A seal member seals the cylinder from the lifter to prevent fuel that leaks from the pressurizing chamber from being mixed with lubricant that lubricates the lifter. A support to which the seal member is attached is formed separately from the cylinder. The support is fixed to the cylinder with the plunger extending through the support.

Abstract: In a fuel path through which fuel is supplied to a pump-cam chamber accommodating a drive shaft and a cam for lubrication, an annular throttle fuel path is formed between an inside wall of a cylindrical body and an outside wall of a sphere, when the sphere is in contact with a seat provided inside the cylindrical body. The seat is provided with cuts through which the fuel flows when the sphere is in contact with the seat. Even if foreign material mixed in fuel once blocks a part of the annular throttled path, the blockage of the foreign material is released, when the fuel flow stops and the sphere leaves the seat, so that the fuel is always supplied sufficiently to the pump-cam chamber, resulting in preventing burn-in of the drive shaft and the cam, in particular, at a high engine revolution range.

Abstract: A piston pump for a slip-controlled, hydraulic brake system of a vehicle. A hollow piston is provided with an inner piston seal that has a sealing lip. During an upward reciprocating motion of the piston, fluid can flow past the sealing lip in a direction of a piston inner (displacement chamber) and constitutes an inlet valve of the piston pump. During a downward movement of the piston the sealing lip is forced by pressure against an inner surface of the piston to prevent a flow of fluid past the sealing lip. The invention obviates the need for a separate inlet valve and makes it possible for the piston pump to be short in length.

Abstract: The invention relates to a piston pump for a slip-controlled hydraulic vehicle brake system. For the sake of a short structural length of the piston pump, piston of the piston pump is a hollow piston, whose interior forms a positive displacement chamber of the piston pump. The piston can be produced economically as a reshaped part, for instance by deep drawing.

Abstract: A plunger pump device includes a housing defining a compression chamber, a plunger slidably accommodated in the housing and exposed to the compression chamber at one end, a drive cam for reciprocating the plunger, a discharge valve connected to the compression chamber, an intake valve connected to the compression chamber, and a low-pressure reservoir for accommodating fluid with a predetermined pressure or more connected to the compression chamber through the intake valve. Even if the intake valve is in a closed position, a small amount of the fluid is discharged from the compression chamber into the low-pressure reservoir side through a slit formed on the intake valve. The small amount of the fluid discharged through the slit is accommodated in a capacity space under a small pressure.

Abstract: A miniature pump equipped with: a pump chamber communicated with a suction port by way of a check valve and communicated with a discharge port by way of another check valve; a driving portion for performing a pump function by increasing and decreasing a volume of the above described pump chamber; a driving plate attached to the above described driving portion for reciprocating the driving portion; a rotating plate fixed to an output shaft of a motor; a ball disposed at a location which is between the above described driving member and the above described rotating plate, and apart from the above described output shaft; and means for applying a force to a surface of the above described driving plate on a side of the above described rotating plate for bringing the above described driving plate into close contact with the above described ball, in which an inclined direction of the above described driving plate is continuously changed by a movement caused due to rotations and revolutions of the above described bal

Abstract: In a vacuum pump of the regenerative type or including a regenerative section in which a rotatable vertical shaft is supported by upper and lower bearings, a lubricating system for lubricating the upper bearing comprising an axial bore extending along the shaft and communicating at its upper end with at least one oil hole in alignment with the upper bearing, the lower open end of the axial bore extending in to a shaft reservoir located in a sump for containing lubricating fluid, the arrangement being such that centrifugal force generated by the rotation of the shaft will cause the lubricating fluid in the shaft reservoir to pass along the axial bore as a thin film towards the oil hole and hence to the upper bearing, in which at least one port is formed in a wall of the shaft reservoir to permit the passage of lubricating fluid therethrough from the sump in a controlled manner dependent upon the head of lubricating fluid in the sump above the port.

Abstract: A piston pump having a piston axially movable against the force of a spring within an operating chamber connected via check valves to an operating cylinder and a hydraulic medium supply. A section of the piston that extends into the operating chamber has a reduced diameter extension which extends from a shoulder of the piston that delimits the operating chamber. The extension includes a thickened free end having a sealing surface facing the shoulder. A valve disk is located and guided on the extension in a gap between the shoulder and sealing surface and is capable of axially reciprocating movements thereon. The valve disk is provided with openings which provide a passageway for hydraulic medium from the operating chamber to a second check valve. The openings are blocked when the valve disk abuts the sealing surface.

Abstract: A swash-plate-end bearing for the motor shaft in a high pressure cleaning appliance which includes a motor and a reciprocating pump driven thereby, wherein the pistons of said pump rest resiliently on a swash plate driven by the motor whose shaft is rotatably mounted at each end whilst being connected at one end in non-rotatable manner to the swash plate, and which also includes at the swash plate end, a roller bearing having two concentric bearing rings, whereby the outer bearing ring is held in an end plate of the motor whilst the inner bearing ring surrounds the motor shaft, in such a manner as to simplify the operation of assembling the motor shaft and the bearing and to make it as independent as possible from unavoidable manufacturing tolerances, it is proposed that the inner bearing ring should surround the motor shaft in floating manner.

Abstract: An improved wear resisting structure of a fuel injection pump is provided. The fuel injection pump has a plunger reciprocating to pressurize fuel within a compression chamber and a cam mechanism installed on a torque input shaft. The cam mechanism revolves following rotation of a torque input shaft to move the plunger. Washers are installed fixedly within washer chambers formed in an inner wall of the housing. The washers work as bearing surfaces which are in contact with and holds the cam mechanism from moving in an axial direction thereof, thereby avoiding excessive wear of portions of the housing.

Abstract: The invention relates to a piston pump (10) for a hydraulic slip-controlled vehicle brake system. In order to reduce a structural length of the piston pump (10), the invention proposes embodying the piston (16) of the piston pump (10) as a hollow piston whose inner chamber constitutes a displacement chamber (40) of the piston pump (10) and inserting an inlet valve (20) of the piston pump (10) into the inner chamber of the piston (16).

Abstract: The invention relates to a piston pump (10) for a hydraulic, slip-controlled vehicle brake system. The piston pump (10) has a piston (20), which is inserted with a part of its length into a sleeve (12). A tubular filter (76) that encompasses the piston (20) is attached to the sleeve (12) and constitutes a captive retainer, which secures the piston (20) in a captive fashion in the sleeve (12). In order to reduce an axial mobility of a sealing ring (14) that seals the piston (20) in the pump housing (16), the invention proposes attaching the filter (76), which limits the axial mobility of the sealing ring (24), to the sleeve (12) in an axially mobile fashion.

Abstract: The invention relates to a piston pump for increasing pressure for liquids, in particular for the camshaft phase adjustment of reciprocating internal combustion engines, said piston pump advantageously being integrated into the housing of the cylinder head. The piston pump for increasing pressure is defined in that it increases an existing fluid pressure to a required fluid pressure and keeps this pressure virtually constant. The piston pump for increasing pressure is advantageously pre-assembled in a sleeve.

Abstract: A fluid pump is provided that produces an outflow of fluid that is not proportional to the speed of the input drive. Thus, the fluid pump can be tuned to provide a substantially constant outflow of fluid irrespective of the speed of the input drive. The fluid pump also provides fluid outflow when the rotational direction of the input drive is reversed.

Abstract: The invention relates to a piston pump for a slip-controlled hydraulic vehicle brake system. To make a piston of the piston pump easy and inexpensive to manufacture, the invention proposes that the piston be comprised of a sleeve-like shaped part and a valve seat part that is made of plastic and is press-fitted into the shaped part. A high-pressure-side sealing lip is formed onto the valve seat part and is of one piece with it. By means of a tubular support body, a restoring spring is supported on the valve seat part spaced apart from a valve seat of the valve seat part and spaced apart from the sealing lip, which prevents the valve seat and the sealing lip from being impaired by the force of the restoring spring.

Abstract: Disclosed is a piston pump having a pump housing with a cylinder head comprised of a first plate and a second plate. The plates which rest against each other and are screwed to the pump housing, have a first conduit which carries low-pressure fuel and leads to a first check valve disposed between the two plates. The check valve communicates with a cylinder chamber of the radial piston pump. A second conduit carrying high-pressure fuel leads from this cylinder chamber to a second check valve, which is disposed between the first plate and the pump housing. Seals that are appropriate to the load, in fact low-pressure seals, are provided in the region of the cylinder head that is subjected to low pressure and high-pressure seals are provided in the region of the cylinder head that is subjected to high pressure.

Abstract: The pump has a body in which at least one cylinder for a piston is fixed by a head having a surface facing a corresponding surface of the body. The head has an intake conduit having an inlet at the surface of the head, and the body has a feed conduit having an outlet located at the surface of the body and at the inlet. Between the surfaces, a first seal is placed about the cylinder, and a second seal about the inlet. The seals are separate and made of elastomeric material. One of the seals is housed inside a circular depression in the seat of the cylinder, so as to engage the lateral surface of the cylinder.

Abstract: In the case of a reciprocating pump for a high pressure cleaning appliance including a pump housing in which there is disposed at least one pumping chamber having an inlet valve, an outlet valve and a reciprocating piston that projects thereinto in sealed manner, said pump housing comprising a pump block and a pump head which abut closely together at a interface, wherein the pumping chambers and/or the connecting conduits penetrate the interface in sealed manner and, in the region of the interface, accommodate inserts that are insertable into the pumping chambers and/or the connecting conduits from the interface, said inserts being fixed between the pump block and the pump head when in their inserted position, it is proposed that the whole construction be simplified by making the inserts themselves and the region of the pumping chambers and the connecting conduits in which the inserts are accommodated out of a thermally softenable synthetic material, and by connecting the inserts to the wall of the pumping ch

Abstract: Cold temperature performance of a pump for a controlled braking systems is enhanced, and internal flow restrictions of the pump are minimized, by placing the poppet return spring in a separate cavity out of the flow path through the pump. The separate spring cavity also allows travel of the poppet to be limited, thereby also limiting the loss of volumetric efficiency due to flow forces generated by cold, viscous fluid pushing the poppet an increasing distance from the seating area.

Abstract: In order to provide a fuel pump in which a piston spring arrangement can be made of inexpensive material, knocking noises of a piston are reduced, and components related to the piston are protected against breakdown, a piston-following spring is provided between a fuel pump body and the piston to lower the piston in response to the rotation of an eccentric cam. A pumping member-moving spring is provided between the fuel pump body and a pin connected to a pumping member, and lowers the pumping member when the piston is moved down. The downward movements of the piston and the pumping member are caused by the springs, so that these springs can be made of inexpensive materials, and enable the piston to reliably follow the eccentric cam.

Abstract: A fuel pump comprises a pumping plunger reciprocable within a plunger bore under the action of a cam drive arrangement. The cam drive arrangement comprises first and second surfaces defining therebetween a chamber, the volume of which can be controlled to control the spacing of the first and second surfaces so as to permit control of the axial length of the cam drive arrangement. The first surface may be defined by a tappet member which acts to transmit a force from the cam drive arrangement to the pumping plunger, the second surface being defined by a piston member which is slidable within a tappet bore formed in the tappet member. The invention also relates to an arrangement for use in a fuel pump comprising a pumping plunger which is reciprocable within a plunger bore under the action of a drive arrangement and a tappet member which is slidable within a further bore provided in a housing for transmitting a force from the drive arrangement to the pumping plunger.

Abstract: The invention relates to a piston pump for a vehicle brake system, in particular an electrohydraulic vehicle brake system. To improve the aspiration performance of the piston pump when the brake fluid is viscous at low the invention proposes a valve opening device, which compulsorily opens the inlet valve, embodied as a spring-loaded check valve, of the piston pump at the onset of a return stroke of the piston. The valve opening device has an opener pin, which is mounted on a valve ball of the inlet valve, and which at the end of a supply stroke of the piston enters a perforated, disklike valve opener part. At the onset of the return stroke, the valve opener part restrains the valve ball by frictional force at its opener pin and thereby opens the inlet valve.

Abstract: A fuel pump comprising a pumping plunger reciprocable within a bore, and a drive arrangement for driving the pumping plunger. The drive arrangement includes a compressible load transmission arrangement for transmitting movement of the drive arrangement to the pumping plunger. The load transmission arrangement comprises first and second surfaces which define, therebetween, a chamber for fluid. The fuel pump also comprises supply means for permitting the chamber to be supplied with fluid, in use, and control means for controlling the flow of fluid from the chamber.

Abstract: The invention relates to a piston pump, for instance for an electrohydraulic vehicle brake system. The invention proposes that a pump piston, on an end toward an eccentric element, be sealed off with a sealing ring, such as a quad ring, that has two axially spaced-apart sealing lips, which sealing ring has radial openings, and also proposes that interstices between the axially spaced-apart sealing lips be connected, through a fluid line, to a fluid supply container from which the piston pump aspirates fluid, or to a pump inlet, whereby in the event of a leak of a sealing lip, the piston pump will aspirate brake fluid through the fluid line and prevent the piston pump from aspirating air from the direction of an eccentric element.

Abstract: A radial piston pump for supplying high fuel pressure in fuel injection systems of internal combustion engines that include a common rail. Pistons, which are disposed in a respective cylinder chamber, each of the pistons have a plate connected to one end. A center of each of the plates is embodied so that the stresses that occur in this location during operation are reduced. Reducing the stresses in each plate center advantageously extends the service life of each of the plates. A perfect function of the plate is thus assured, even at peak pressures of up to 2000 bar.

Abstract: A piston pump intended especially for use in a slip-controlled hydraulic vehicle brake system. The piston pump is inserted into a cylinder bore, the piston pump has a piston, a bush, and a closure element that tightly closes the cylinder bore. The closure element is joined radially movably to the bush, for instance via caulking. This joint has the advantage that the piston pump can be assembled into a compact, easily manipulated, and sturdy component unit, and that the closure element and the bush are aligned with one another on being inserted into the cylinder bore.

Abstract: The invention is based on a radial piston pump (1) with a pump body (2), in which pump body (2) are placed pistons (4), and cylinders (5) arrayed radial to a cam (14) and the pistons (4) upon an inward thrust suck in fluid by means of suction side intakes (17) and upon an outward thrust, the pistons (4) impel fluid through pressure openings (7) in the outer end walls (6) of the cylinder (5) into a plenum (10). It is proposed, that in the base of the cylinders (4) respectively a connection boring (32) is made to the cam (14), which connection boring (32) is controlled by a relief valve (18). Upon the exceeding of its opening pressure the relief valve (18) opens and pressure peaks in the cylinder (5) can be diminished by means of said connection boring. At the same time, a pressure buffer between the base of the piston (4) and the bearing shell (16) is formed.

Abstract: The invention is directed to a piston pump for a hydraulic vehicle brake system. For simple and inexpensive manufacturability, the piston pump embodies an outlet conduit as a groove in a sleeve bottom and a sealing part. As a result, the sleeve and the sealing part can be manufactured in a non-cutting manner by means of forming. Another advantage of letting the outflow conduit into the sleeve bottom is that the outlet conduit is disposed a small distance in the axial direction from a valve seat of an outlet valve, which counteracts noise production.

Abstract: A piston pump for a hydraulic slip-controlled brake system for a vehicle. To seal off and guide a piston of the piston pump in a bush, the piston pump includes a seal of rigid plastic which has a spreader face in the form of an internal cone. A piston restoring spring presses directly or indirectly against the spreader face via a spreader ring with a conical counterpart face and thereby presses the seal into sealing contact with the bush. The piston pump has the advantage that no separate sealing ring or guide ring is needed for the piston, and that friction and wear are both only slight.

Abstract: The invention is based on a radial piston pump (1) with a pump body (2), in which pump body (2) are placed pistons (4), and cylinders (5) arrayed radial to a cam (14) and the pistons (4) upon an inward thrust suck in fluid by means of suction side intakes (17) and upon an outward thrust, the pistons (4) impel fluid through pressure openings (7) in the outer end walls (6) of the cylinder (5) into a plenum (10) whereby the check valves (22) are formed from an annular coil spring valve (9) which cover the pressure ports (7) and the thereto connected stress relieving corrugations (8), and upon the exceeding of a specified threshold transport pressure, the respective pressure opening (7) opens to the plenum (10). The proposal is made, that a stress relieving zone (27) of a piston-cylinder unit (4, 5) be connected to the pressure zone (5, 7, 26) of a neighboring piston-cylinder unit (4, 5).

Abstract: A high pressure fuel pump has a plunger that extends through a cylinder and is reciprocally located in a pressurizing chamber. The plunger is reciprocated by a lifter and changes the volume of the pressurizing chamber to pressurize fuel in the pressurizing chamber. A seal member seals the cylinder from the lifter to prevent fuel that leaks from the pressurizing chamber from being mixed with lubricant that lubricates the lifter. A support to which the seal member is attached is formed separately from the cylinder. The support is fixed to the cylinder with the plunger extending through the support.

Abstract: A multi-chamber positive displacement pump comprises a unitary housing in which is formed a plurality of cylinders. A pumping plunger is slidably mounted in each cylinder to define a pumping chamber. Means are provided for reciprocating the pumping plungers in order cyclically to vary the volume of the pumping chambers to effect delivery of a pumped fluid from the pumping chambers. A delivery passage is connected to each of the pumping chambers to receive pumped fluid therefrom, the delivery passage comprising at least one gallery formed in the unitary housing and open to an end face of the housing and passageways which extend through the unitary housing from the galleries to the pumping chambers. The galleries are closed by an end plate which is secured to the unitary housing. Feed passages and working fluid passages may likewise be defined by combination of galleries in the end face and passageways in the unitary housing.

Abstract: The invention relates to a piston pump for a slip-controlled, hydraulic vehicle brake system. In order to be able to simply and inexpensively produce the piston pump as a stepped piston pump, the invention embodies a piston as a tubular deep drawn part made of sheet metal, with an outwardly protruding circumferential bead. The bead is produced by axially compressing the piston. The bead constitutes an axial support for a guide ring and sealing ring placed onto the piston. A disk-shaped, abrasion resistant striking piece is press-fitted into an open end of the tubular piston, and is used by the piston for resting against a circumference of a cam element used for the stroke drive.

Abstract: A piston pump for a slip-controlled hydraulic vehicle brake system. For the sake of economical production, the piston pump is embodied with a plastic bush and with a needle of a needle bearing as the piston, and that an inlet valve is accommodated in a valve seat part (96) that is inserted into the bush (16). The invention has an advantage that both the inlet valve and an outlet valve can be mounted coaxially on the bush, and that the bush, because of its elasticity since it is made of plastic, brings about a favorable closing performance of the two valves.