Abstract: A vane pump (20) is provided which has an output pressure hat can be selected from a continuous range of pressures, independent of the operating speed of the pump. The pump has first (68) and second (72) control chambers which create opposed forces on the pump control ring (40) to selectively move the pump control ring (40) between maximum displacement and minimum displacement positions. In one embodiment, the control chamber (68) which urges the ump control ring to the minimum displacement position is continually supplied with pressurized working fluid during operation of the ump while the control chamber (72) which urges the pump control ring to the maximum displacement position can selectively be supplied with pressurized working fluid, isolated, or can be relieved of pressurized working fluid to alter the displacement of the pump.

Abstract: A variable displacement vane pump that assuredly suppresses seizing of mutually contacting surfaces of a pressure plate and a rotor where the pressure plate is formed, at one side surface thereof that slidably contacts the rotor, with an annular lubricating groove. The lubricating groove is on a seal surface of the side surface at a position between arcuate back pressure grooves formed on the seal surface and a through opening which is formed in a center part of the pressure plate to receive the drive shaft. A radial width of the lubricating groove is set to a range from 10% to 25% of a radial width of the seal surface, and a distance from a center of the radial width of the lubricating groove to an inner cylindrical surface of the through opening is set to a range from 24% to 70% of the radial width of the seal surface.

Abstract: A variable capacity vane pump has a pump control ring that is moveable to alter the capacity of the pump. A control chamber is formed between the pump casing and the control ring. The control chamber is operable to receive pressurized fluid to create a force to move the control ring to reduce the volumetric capacity of the pump. A primary return spring acts between control ring and the casing to bias the control ring towards a position of maximum volumetric capacity. A secondary return spring is mounted in the casing and is configured to engage the control ring after the control ring has moved a predetermined amount. The secondary return spring biases the control ring towards a position of maximum volumetric capacity. The secondary return spring acts against the force of the control chamber to establish a second equilibrium pressure.

Abstract: In an exemplary embodiment, the momentum of oil-containing air rotating with a crankshaft counterweight in an engine crankcase is converted to static pressure by blocking the flow and directing the resulting static pressure through an orifice to a vent chamber wherein the pressure acts against a cam ring of a variable displacement oil pump. The arrangement modifies the action of an oil pressure control by increasing the effective pump outlet pressure as a function of engine speed using relatively low cost modifications of the engine and oil pump. This pressure may also be used in various ways to modify the control functions of other devices.

Abstract: A vane pump with a reduced rotor diameter is provided. The reduced rotor diameter allows a reduction in the overall size of the pump which allows the pump to be used in circumstances wherein sufficient packaging volume does not exist for conventional vane pumps. Further, the reduced rotor diameter permits operation of the pump at a higher speed, in comparison to conventional vane pumps, for a given working fluid and pump rate. The rotor includes an integrally formed drive shaft and a cylindrical rotor head. Both fixed displacement and variable displacement embodiments are shown.

Abstract: A variable displacement vane pump includes a rotor, a cam ring; and a pump casing including first and second side walls disposed on both sides of the cam ring, and a circumferential wall surrounding the cam ring and defining first and second pressure chambers. A pressure introduction groove is formed in a sliding contact surface between the cam ring and one of the first and second side walls, and arranged so that a pressure lower than an outlet pressure is introduced.

Abstract: In a variable displacement pump, an outer peripheral surface approximately in an opposite side to a portion supported to an oscillation supporting point in a cam ring with respect to a pump shaft is formed as a convex surface portion holding a seal member brought into slidable contact with an inner peripheral surface of an outer case, and an inner peripheral surface of the outer case with which the seal member held to the convex surface portion of the cam ring is brought into slidable contact is formed as a circular arc surface around the oscillation supporting point.

Abstract: A variable delivery vane pump, in particular for oil, is provided with a stator (10) eccentrically mounted about a rotor (9), which is adapted to turn about one own longitudinal axis (6), and presents a plurality of grooves (15) radially outwardly opened and slidingly engaged, each, by a respective vane (17) the vanes (17) being arranged essentially in contact with the stator (10) by interposing at least one sliding element (19; 27) extending about the axis (6) according to an angle smaller than 360°.

Abstract: A variable displacement vane pump, including a pump body, a driving shaft, a rotor, a cam ring swingable around a swing fulcrum, first and second support members on opposite axial sides of the cam ring, a suction port and a discharge port disposed on at least one of the support members, a seal dividing a space on an outer circumferential side of the cam ring into a first fluid pressure chamber defined in a direction in which the cam ring is swung to cause increase in a flow rate of a working fluid discharged, and a second fluid pressure chamber defined in a direction in which the cam ring is swung to cause decrease in the flow rate of the working fluid discharged, and a plunger biasing the cam ring from a side of the second fluid pressure chamber toward a side of the first fluid pressure chamber.

Abstract: A variable displacement vane pump includes a pump body, a rotor, an annular cam ring, a rear body closing the pump body, a low pressure supply passage constantly connecting the inlet passage and the other of the first fluid pressure chamber and the second fluid pressure chamber, a low pressure introduction port formed in the other of the pressure plate and the rear body, and opened in the other of the first fluid pressure chamber and the second fluid pressure chamber, and a low pressure introduction passage formed in the other of the pressure plate and the rear body, the low pressure introduction passage connecting the low pressure introduction port and the inlet side vane back pressure grooves.

Abstract: A variable displacement engine oil vane pump includes a displacement control for controlling displacement of the pump. The control includes a cam ring in a housing pivotally connected to a wall of the housing by a pivot. The cam ring is internally engaged by slide vanes. A control chamber is defined by the cam ring and the housing wall. A control orifice provides for communication of control oil from a pressurized source to the control chamber. A vent chamber is generally opposite the control chamber and is defined by the cam ring and the housing wall. A dump chamber is defined by the cam ring and the housing wall and is generally disposed between the control chamber and the vent chamber. A dump orifice provides for communication between the control chamber and the dump chamber. A vent orifice provides for communication between the vent chamber and the dump chamber.

Abstract: A pump apparatus includes a pump housing; a drive shaft; a pump element; a cam ring arranged to vary an inherent discharge amount based on the eccentric amount of the cam ring; a steering state sensing section configured to sense or estimate a steering angle, a steering angular speed or a steering angular acceleration, and to output the steering angle, the steering angular speed or the steering angular acceleration as a steering state sensing signal; and a solenoid configured to be controlled to suppress the eccentric amount of the cam ring so as to decrease the inherent discharge amount with respect to the steering state sensing signal when the vehicle speed is equal to or greater than a first predetermined vehicle speed, relative to the inherent discharge amount when the vehicle speed is smaller than the first predetermined vehicle speed.

Abstract: A variable displacement vane pump includes a first body, a second body, an adapter ring, a cam ring, and a rotor. The first body includes a cylinder portion, and a base portion covering a first longitudinal end of an inner space of the cylinder portion. The second body covers a second longitudinal end of the inner space of the first body. The adapter ring has an outer radial periphery fitted and fixed to an inner radial periphery of the cylinder portion of the first body. The cam ring is mounted inside the adapter ring and supported by the adapter ring for lateral motion in contact with the contact area of the adapter ring. The rotor is mounted inside the cam ring. The adapter ring has a radial thickness that gradually increases when followed longitudinally of the adapter ring from the base portion of the first body toward the second body.

Abstract: A variable displacement vane pump includes at least two regulation chambers to provide a regulating force to the cam ring to counter the force applied to the cam ring by a regulating spring and reduce pulsation in the output working fluid from the pump. A first regulation chamber is part of the pump outlet and is in fluid communication with the outlet port of the pump via a passage which allows the pump to be fabricated from a diecast process or the like. A second regulation chamber is connected to the first chamber via an orifice which reduces the pressure of working fluid supplied from the first chamber to the second. The pump outlet need not overlie the pump outlet. Further, a pump with an inlet port with a relatively large initial cross-sectional flow area inhibits cavitation of the working fluid when the pump is operated at higher operating speeds.

Abstract: A variable capacity vane pump includes a pump casing having a pump chamber with an inlet and an outlet port. A pump control ring is moveable within the pump chamber to alter the capacity of the pump. A vane pump rotor is rotatably mounted within the pump control ring and includes a plurality of slidably mounted vanes engaging the inside surface of the pump control ring. First and second control chambers between the pump casing and the pump control ring are operable to receive pressurized fluid to urge the pump control ring to reduce the volumetric capacity of the pump. A return spring biases the pump ring toward a position of maximum volumetric capacity against the force of the first and second control chambers to establish an equilibrium pressure. The supply of pressurized fluid to the second control chamber may be varied to change the equilibrium pressure of the pump.

Abstract: The present disclosure relates to a vane cell pump (12) which includes an internal rotor (16) and a plurality of vanes (20) which are displacably mounted in a radial manner in the internal rotor, essentially, in radial slots (18) and are directly or indirectly guided on the internal circumferential surface (26) of a stator (28). The axis of the stator and the axis of the internal rotor are offset in relation to each other and the stator (28) can be adjusted in relation to the internal rotor (16) in the radial direction and the offset can be altered. The stator (28) comprises a pivotable bearing (36) which is arranged in the housing of the vane cell pump. At least one piston section (42) protrudes from the stator, whereby the piston axis thereof (44) extends in the direction of the periphery to the pivotable bearing (36).

Abstract: A vane machine comprises an inner rotor (28) and an outer rotor (51). A plurality of radially extending vane elements (32) separates first vane chambers (89) from one another. The van elements (32), with a radially inner end region (34), are accommodated in the inner rotor (28) in a radially displaceable manner and, with a radially outer end region (36), are accommodated in the outer rotor (51) in a pivotable manner. It is proposed that the radially inner end regions (34) of the vane elements (32) be accommodated in the inner rotor (28) at a fixed angle and that the outer rotor (51) comprise individual shoes (38) which are separate for each vane element (32) and in which the vane elements (32) are accommodated in a pivotable manner.

Abstract: A pump system including a control system for controlling a variable flow pump for controlling oil flow and oil pressure in a hydraulic circuit in an engine. The system includes a pump member, an actuating member capable of controlling the flow generated by the pump member, and a solenoid valve system including a solenoid valve portion and a pressure regulator valve portion. The solenoid valve system is operably associated with the pump and the pressure regulator valve portion is operably associated with the actuating member for selectively controlling the flow generated by the pump member. An electronic control unit is operably associated with the solenoid valve portion, wherein the electronic control unit is selectively operable to provide an input control signal to the solenoid valve portion for controlling oil flow and oil pressure.

Abstract: The present invention is a variable displacement pump having an inner rotor rotatable about a first axis and having at least two slots. The pump also has at least two vanes, each located in a distinct one of the at least two slots. The pump also has an outer rotor rotatable about a second axis, operably associated with the inner rotor, the outer rotor having two or more recesses, each configured to receive one of the vanes. The pump also includes an expandable chamber formed by the outer rotor and the inner rotor, an eccentric ring surrounding the outer rotor, and a housing. The eccentric ring is located within the housing for adjusting the relative relationship between the first axis and the second axis in order to vary the displacement of the pump.

Abstract: A lubrication system for a power transmission device includes a variable displacement vane pump including a moveable control ring for varying the displacement of the pump. A linear actuator directly acts on the control ring for moving the control ring between maximum and minimum pump displacement positions. The linear actuator includes an electric motor for rotating a drive member. The drive member engages a driven actuator shaft to cause linear translation of the actuator shaft in response to rotation of the drive member. A control system includes a controller for signaling the actuator to extend or retract the actuator shaft to vary the pump displacement.

Abstract: In a variable displacement pump, a first groove always connected to a second hydraulic chamber is provided in a slide surface of a cam ring facing to an end surface of a side plate, and a second groove always connected to a suction port is provided in the end surface of the side plate, whereby when the cam ring is moved to a moving end side in which a volumetric capacity of a pump chamber is reduced, the first groove and the second groove are connected, and the second hydraulic chamber can be connected to the suction port by the grooves.

Abstract: A variable displacement vane-type fluid pump is provided which permits improved regulation of the pump discharge such that the pump can meet the various requirements of lubrication for internal combustion engines at all speeds with minimized use of power. Of course, the vane pump may also be utilized in a wide range of power transmission and other fluid distribution applications. The vane pump of the invention may also use both hydrostatic and mechanical actuators to control the position of its containment ring or eccentric ring and hence, regulate the output of the pump. According to yet another aspect of the present invention, to prevent inlet flow restriction or cavitation, a valve may be provided to permit some of the pump outlet or discharge flow to bleed into the pump inlet to provide needed velocity energy to the fluid flow into the pump inlet.

Abstract: A variable capacity vane pump (100) has a pump housing (10) having a high-load bearing part (10a) on which a higher load is exerted than another part when the pump vane pump (100) operates. A control valve (21) for varying a capacity of the vane pump (100) is provided in a valve housing (28) which is formed integrally in the pump housing (10). By arranging the valve housing (28) on the same side of the pump housing (10) as the high-load bearing part (10a) with respect to the rotation axis of the vane pump (100), the high-load bearing part (10a) can be reinforced without increasing the size of the vane pump (100).

Abstract: The invention relates to a vane pump (1), in particular a regulatable oil pump for a lubricating system, with a pump housing (2) with at least one housing tank (6) and with a vane rotor (11) disposed in the housing tank (6) mounted so that it can be rotated by means of a drive shaft (10) in the pump housing (2) constituting an axis of rotation (23) which provides a mount for vanes (15) in approximately radially extending fitting slots (14). An adjusting ring (27) is provided enclosing the vane rotor (11) and circumferentially bounding pump cells (26) which, by means of a cylindrical internal wall surface (31), can be displaced between a concentric position with respect to the vane rotor (11) and an eccentric position relative thereto, to which pressured is applied by positioning torques caused by the medium pressure and a positioning mechanism (47) in order to regulate a pressure level.

Abstract: A radially pressure balanced vane pump includes a housing that defines an inlet port and a discharge port. A cam block disposed within the housing defines a continuous inner surface. A plurality of vanes are supported within rotor slots and rotated above a shaft. Each vane includes a vane tip having a radius with a centerline offset from the centerline of the vane. A pressure biasing the vane into contact with the cam block is distributed over the vane tip radius. Further, the vanes are biased into contact with the inner surface of the cam block by communication of discharge pressure under the vane. The vane tip radius along with the pressure balance between under vane and under vane discharge pressure provide for the use of low cost and easily fabricated ductile steels.

Abstract: [Task] To provide a variable displacement vane pump that assuredly suppresses seizing of mutually contacting surfaces of a pressure plate and a rotor. [Means for Achieving the Task] In this variable displacement vane pump, pump elements, such as a drive shaft 7, a rotor 8 and a pressure plate 11 are installed in a receiving space 2a of a front body 2, and an open side of the receiving space 2a is closed by a rear body 3. The pressure plate is formed, at one side surface thereof that slidably contacts the rotor, with an annular lubricating groove 44, the lubricating groove 44 being provided on a seal surface 43 of the side surface at a position between each of arcuate back pressure grooves 41 and 42 which are formed on the seal surface 43 and a through opening 26 which is formed in a center part of the pressure plate to receive the drive shaft.

Abstract: A novel variable displacement vane pump is provided wherein pressurized working fluid is provided to a portion of the pump chamber to act on the outside of the capacity varying ring to substantially balance the force created by the high pressure working fluid inside the ring. As the resultant high pressure force acting on the pivoting pin is reduced, the movement of the displacement control ring is smoother, reducing undesirable hysteresis, the wear on the pin is reduced and the additional force required to move the ring to vary the volumetric displacement of the pump is less than would otherwise be needed, allowing the related control mechanisms to be smaller.

Abstract: A cylinder body is sandwiched between a front head and a rear head. A high pressure port is formed in the front head. A roller of a piston is configured such that top and bottom end surfaces thereof have different widths. The roller is arranged such that one of the top and bottom end surfaces having a larger width faces the front head 7.

Abstract: A system for controlling the pumping capacity of a lubricant pump for an internal-combustion engine, having a vane cell pump (2) which has a rotor body (4), rotor blades (10) which can be radially displaced in the rotor body as well as a lifting ring (12) (stator) whose position can be adjusted with respect to the axis of rotation of the rotor for changing the delivery volume as a function of operating parameters of the internal-combustion engine. The lifting ring (12) is linked to an adjusting piston (28) guided in a valve bore (30) of a pressure regulating valve (26), which adjusting piston (28) is acted upon by engine oil pressure on a piston front side (34), the piston front side (34) being connected with the piston rear side (37) by way of a throttle bore (62).

Abstract: Vane pump (10) mechanical losses are reduced by removing vane friction losses and replacing them with lower magnitude journal bearing fluid film viscous drag losses. A freely rotating cam ring (70) is supported by a journal bearing (80). A relatively low sliding velocity is imposed between the cam ring and the vanes (26). This permits the use of less expensive and less brittle materials in the pump by allowing the pump to operate at much higher speeds without concern for exceeding vane tip velocity limits.

Abstract: A variable displacement vane pump includes at least two regulation chambers to provide a regulating force to the cam ring, to counter the force applied to the cam ring by a regulating spring, to reduce pulsation in the output working fluid from the pump. A first one of the chambers is part of the pump outlet and is in fluid communication with the outlet port of the pump via a passage which allows the pump to be fabricated from a diecast process oath like. A second regulation chamber is connected to the first chamber via an orifice which reduces the pressure of working fluid supplied from the first chamber to the second. The configuration and design of pumps in accordance with the present invention allows for flexible packaging for the pump, as the outlet need not overlie the pump outlet. Further, a pump with an inlet port with a relatively large initial cross-sectional flow area is taught to inhibit cavitation of the working fluid when the pump is operated at higher operating speeds.

Abstract: In a variable displacement pump, a first groove always connected to a second hydraulic chamber is provided in a slide surface of a cam ring facing to an end surface of a side plate, and a second a groove always connected to a suction port is provided in the end surface of the side plate, whereby when the cam ring is moved to a moving end side in which a volumetric capacity of a pump chamber is reduced, the first groove and the second groove are connected, and the second hydraulic chamber can be connected to the suction port by the grooves.

Abstract: A variable capacity rotary compressor capable of equalizing an interior pressure (i.e., discharge pressure) of a hermetically sealed container with an interior pressure of a compression chamber where an idling operation is performed, resulting in a reduction of rotation resistance of a rotary shaft. The variable capacity rotary compressor includes housings disposed in the hermetically sealed container and having an interior space partitioned by intermediate plates into first and second compression chambers with different capacities, a rotary shaft rotatably disposed in the two compression chambers, eccentric units to selectively induce a compression operation in one of the two compression chambers depending on a rotational direction of the rotary shaft, and a pressure adjustment unit to apply the discharge pressure of the hermetically sealed container to one of the compression chambers where the idling operation is performed.

Abstract: A variable displacement vane pump includes: a cam ring defining first and second fluid pressure chambers on both sides thereof; and a rotor mounted inside the cam ring, the rotor defining an annular chamber outside thereof. Arranged outside of the rotor, vanes divide the annular chamber into a plurality of pump chambers. A suction port is defined in a section of the annular chamber in which each of the pump chambers expands with the rotation of the rotor, while a discharge port is defined in a section of the annular chamber in which each of the pump chambers contracts with the rotation of the rotor. A first fluid passage is connected to one of the first and second fluid pressure chambers. A second fluid passage is connected to one of the suction port and the discharge port. An electromagnetic valve controls fluid communication between the first and second fluid passages.

Abstract: A bearing assembly is provided for a fuel delivery system that includes a pump (10) having a housing that rotatably receives a rotor (20) carrying vanes (26) thereon, a cam ring (70) received between the housing and rotor (20), and a support member of yoke (50) encompassing the cam ring (70) to selectively vary fuel flow. The bearing assembly (80) is a journal bearing between the yoke (50) and the cam ring (70) and includes an annular surface having a central opening therethrough. The annular surface includes a first, high pressure pad (102) and a second, low pressure pad (104) substantially diametrically opposite the first pad and separated by first and second lands (106, 108). The circumferential extent of the first pad (102) is at least as great as an inner diameter of the cam ring (70). Circumferential ends of the second pad (104) are wider than circumferential ends of the first pad.

Abstract: A variable displacement vane pump, including a pump body, a driving shaft, a rotor, a cam ring swingable around a swing fulcrum, first and second support members on opposite axial sides of the cam ring, a suction port and a discharge port disposed on at least one of the support members, a seal dividing a space on an outer circumferential side of the cam ring into a first fluid pressure chamber defined in a direction in which the cam ring is swung to cause increase in a flow rate of a working fluid discharged, and a second fluid pressure chamber defined in a direction in which the cam ring is swung to cause decrease in the flow rate of the working fluid discharged, and a plunger biasing the cam ring from a side of the second fluid pressure chamber toward a side of the first fluid pressure chamber.

Abstract: In a hydraulic pump, a cam ring is provided in a cylindrical adaptor for movement in a radial direction, and a differential pressure control valve is provided to control internal pressure and load pressure at the front and back sides of a variable orifice to be introduced into action chambers and formed at the opposite sides of the cam ring for controlling a discharge amount of the pump in accordance with the rotation speed of the pump. The differential pressure control valve is operated under the internal pressure and load pressure respectively introduced into action chambers and the load of a thrust spring biasing the differential pressure control valve toward the internal pressure chamber. The load of the thrust spring is increased or decreased in accordance with an increase or a decrease of the load pressure.

Abstract: Vane pump (10) mechanical losses are reduced by removing vane friction losses and replacing them with lower magnitude journal bearing fluid film viscous drag losses. A freely rotating cam ring (70) is supported by a journal bearing (80). A relatively low sliding velocity is imposed between the cam ring and the vanes (26). This permits the use of less expensive and less brittle materials in the pump by allowing the pump to operate at much higher speeds without concern for exceeding vane tip velocity limits.

Abstract: A vane pump is disclosed for use with gas turbine engines which has pressurized fluid supplied to the undervane portion of the vane elements to balance the forces imparted thereon. The vane pump includes a pump housing, a cam member, a cylindrical rotor member and a chamber. The chamber is defined within the housing and positioned for fluid communication with the undervane portion of each vane element to provide a desired pressure thereto. The chamber is in fluid communication with a first pressure source and a second pressure source, wherein the first pressure source is associated with the discharge arc segment of the pumping cavity, and the second pressure source is associated with the inlet arc segment of the pumping cavity.

Abstract: Within a cam ring (8), a rotor having a plurality of vanes (27) is eccentrically disposed. A metering orifice (136) is provided halfway on a discharge passage (135) of pressure fluid discharged from the pump, and a control valve is activated due to a pressure difference between the upstream and downstream sides of the metering orifice (136). A fluid pressure of the first fluid pressure chamber (21) is controlled by activation of the control valve (123). The second fluid pressure chamber (22) is shut off from the control valve (123) to introduce a pressure on the suction side at any time. To return the cam ring (8) in a direction of expanding a pump chamber (11), an internal pressure of the cam ring (8) is applied in the return direction.

Abstract: An auxiliary solenoid controlled variable displacement power steering pump, hydraulic systems incorporating same, and method for improving the efficiency of variable displacement power steering pumps. In one embodiment, a rotor is arranged within a pump body, and a cam fitted on an outer periphery of the rotor and movably arranged within the pump body to form a variable volume pump chamber. The cam is biased towards a position within the pump body to create maximum displacement. A mechanism is provided for forcing the cam into a position of fixed minimum or reduced displacement under certain conditions, such as low engine speed and power steering demand. In a preferred embodiment, the mechanism comprises a solenoid driven connecting rod that is operatively connected to the cam. Activation of the solenoid forces the cam to a position of fixed minimum or reduced displacement.

Abstract: A variable displacement vane-type fluid pump is provided which permits improved regulation of the pump discharge such that the pump can meet the various requirements of lubrication for internal combustion engines at all speeds with minimized use of power. Of course, the vane pump may also be utilized in a wide range of power transmission and other fluid distribution applications. The variable displacement vane pump of the invention may utilize both hydrostatic and mechanical assistance in radially positioning its vanes to ensure efficient and quiet operation of the pump and to facilitate priming of the pump. The vane pump of the invention may also use both hydrostatic and mechanical actuators to control the position of its containment ring or eccentric ring and hence, regulate the output of the pump.

Abstract: A fixed displacement pump includes a housing having a cavity, an inlet, and an end cap with alignment portions therein. A cam ring pivotally associated within the cavity includes adjustment portions. The cam ring is aligned in a fixed position via a pin inserted through both a select adjustment portion and a corresponding alignment portion. The adjustment portion selected determines both rotational direction and displacement of the pump. The cam ring also includes recesses positioned adjacent the inlet to facilitate porting of fluid through the pump. A rotor mounted within the cam ring includes roller slots having groove segments. The groove segments are positioned in an arcuate arrangement about the rotor to facilitate porting of fluid through the pump. The rotor also includes undercut portions positioned between the roller slots in an arcuate arrangement on an outer edge of the rotor to facilitate porting of fluid through the pump.

Abstract: A fuel metering unit including a pump having a rotor with a plurality of slots. The pump also includes a pivotally movable cam ring coaxially arranged with respect to the rotor. Vanes are slideably disposed in the slots for maintaining contact with the cam ring during movement thereof. A servovalve has a motor and nozzles operatively connected to the pump such that increased flow through the first nozzle pivots the ring of the pump toward maximum while increased flow through the second nozzle pivots the ring toward minimum. An arm extends between the nozzles for varying fluid flow therethrough. The arm couples to the motor such that the motor moves the arm. A flow meter connects to the pump and an end of the arm for applying a force against the arm to assist in maintaining position of the arm.

Abstract: A fixed displacement pump includes a housing having a cavity, an inlet, and an end cap with alignment portions therein. A cam ring pivotally associated within the cavity includes adjustment portions. The cam ring is aligned in a fixed position via a pin inserted through both a select adjustment portion and a corresponding alignment portion. The adjustment portion selected determines both rotational direction and displacement of the pump. The cam ring also includes recesses positioned adjacent the inlet to facilitate porting of fluid through the pump. A rotor mounted within the cam ring includes roller slots having groove segments. The groove segments are positioned in an arcuate arrangement about the rotor to facilitate porting of fluid through the pump. The rotor also includes undercut portions positioned between the roller slots in an arcuate arrangement on an outer edge of the rotor to facilitate porting of fluid through the pump.

Abstract: A variable displacement vane-type fluid pump is provided which permits improved regulation of the pump discharge such that the pump can meet the various requirements of lubrication for internal combustion engines at all speeds with minimized use of power. Of course, the vane pump may also be utilized in a wide range of power transmission and other fluid distribution applications. The vane pump of the invention may also use both hydrostatic and mechanical actuators to control the position of its containment ring or eccentric ring and hence, regulate the output of the pump. According to yet another aspect of the present invention, to prevent inlet flow restriction or cavitation, a valve may be provided to permit some of the pump outlet or discharge flow to bleed into the pump inlet to provide needed velocity energy to the fluid flow into the pump inlet.

Abstract: In a hydraulic pump, a cam ring 21 is provided in a cylindrical adaptor 13 for movement in a radial direction, and a differential pressure control valve 31 is provided to control internal pressure and load pressure at the front and back sides of a variable orifice 54 to be introduced into action chambers 51a and 51b formed at the opposite sides of the cam ring for controlling a discharge amount of the pump in accordance with the rotation speed of the pump. The differential pressure control valve is operated under the internal pressure and load pressure respectively introduced into action chambers 52a and 52b and the load of a thrust spring 33 biasing the differential pressure control valve toward the internal pressure chamber 52a. The load of the thrust spring is increased or decreased in accordance with an increase or a decrease of the load pressure.

Abstract: The invention relates to a vane-cell pump comprising a pump rotor (20), provided with a radially displaceable rotor blade (22). Said pump rotor is mounted in a pump stator (12) which can be pivoted inside a pump bearing house (10) around a stationary pivotal axis (34) in a radial position with regard to said pump rotor. A control device (30) is associated with the pump stator (12) for automatic pressure adjustment. Said control device has an actuating member protruding on the outside, therefrom, perpendicular to the pivotal axis thereof. The actuating member forms a pivoting piston (38) in a guide element (10) of the pumpbearing housing (10) which is directly impinged upon by a pumping medium. The pivotable piston can pivot in a direction against the action of a pressure spring (50).

Abstract: An adjustable fixed displacement vane pump is disclosed which includes a pump housing defining an interior pumping chamber having a central axis extending therethrough, a rotor member mounted for rotational movement within the interior pumping chamber of the pump housing about an axis aligned with the central axis of the interior pumping chamber, the rotor member having a central vane section with a plurality of circumferentially spaced apart radial vane slots formed therein, each vane slot supporting a corresponding vane element mounted for radial movement therein, and each vane element having an outer tip surface, a cam member mounted for pivotal movement within the interior pumping chamber of the pump housing about a fulcrum axis extending parallel to the central axis of the rotor member, the cam member defining a cam body having a circular bore extending therethrough for receiving the rotor member, the circular bore forming a cam chamber defining a cam surface making continuous contact with the outer tip

Abstract: In a variable displacement pump, a pressurizing cylinder is provided on an opposite side of the first fluid pressure chamber, holding the cam ring there between, and a piston inserted to the pressurizing cylinder collides with the cam ring. An oil chamber of the pressurizing cylinder is interposed in a pump discharge side passage, and wherein a pressure in an upstream side of the main throttle provided in the pump discharge side passage is introduced to the first fluid pressure chamber and the oil chamber of the pressurizing cylinder, and a pressure in a downstream side of the main throttle is introduced to the second fluid pressure chamber.