Abstract: A gear pump with internal rotors for pumping fluids includes one or more internal gear rotors, a cover, at least one infeed reniform suction chamber in a pump housing, at least one discharge reniform pressure chamber in the pump housing, and a reniform pressure chamber extension. Each gear rotor has teeth, is located in the pump housing, and is driven by a central shaft. The cover seals the pump housing and is adjacent to the one or more internal gear rotors. Each infeed reniform suction chamber has a first end and a second end, and at least partially covers end areas of the teeth. Each discharge reniform pressure chamber has a first end and a second end, and at least partially covers the end areas of the teeth. The reniform pressure chamber extension has a first end and a second end and is located in the cover opposite the discharge reniform pressure chamber. The first end of the discharge reniform pressure chamber is substantially adjacent to the first end of the reniform pressure chamber extension.

Abstract: An outer rotor and an inner rotor are formed of sintered aluminum alloy. The sintered aluminum alloy contains 0.5 wt % to 11 wt % of aluminum nitride. Porosity of the sintered aluminum alloy for outer rotor is 3 vol % to 15 vol %. Porosity of the sintered aluminum alloy for inner rotor is 2 vol % to 10 vol %. Outer rotor and inner rotor are set in a pump case. A rotary driving shaft formed of steel is inserted to a through hole of inner rotor. A press fit member is inserted at a press fit surface of inner rotor and rotary driving shaft. Accordingly, sliding members formed of sintered aluminum alloy which reduces seizure and abrasive wear of the inner and outer rotors can be provided, and in addition, an oil pump of which wear and damage at the inner rotor inner diameter surface is suppressed, can be provided.

Abstract: A fuel pump comprises a pump unit and a motor unit. The pump unit is a trochoid gear type having rotors in a pump chamber defined by a pair of side plates and a cylindrical housing. A disk plate is attached to the side plate to provide an arcuate-shaped pressure pulsation reducing passage jointly with the side plate. Protrusions or recesses are provided in the passage to cause turbulence in fuel flowing through the passage. This turbulence scatters pressure pulsation in the fuel thereby to reduce the pressure pulsation.

Abstract: An oil pump rotor in which there is formed an inner rotor 10 having n teeth, the tips of the teeth prescribed by an epicycloid curve generated by a first outer rotating circle Ei which rotates along the base circle Bi of inner rotor 10, and the tooth spaces prescribed by a hypocycloid curve generated by a first rotating circle Hi which turns along the base circle Bi of inner rotor 10, and an outer rotor 20 having n+1 teeth, the tooth spaces prescribed by an epicycloid curve generated by a second rotating circle Eo which turns along the base circle Bo of outer rotor 20 and the tips of the teeth prescribed by a hypocycloid curve generated by a second inner rotating circle Ho which rotates along the base circle Bo of outer rotor 20; wherein each of the rotors are formed to satisfy:Do>Di, di>dowhere Di, di, Do, and do designate the diameters of Ei, Hi, Eo, and Ho, respectively.

Abstract: A filling member-less internal-gear unit has a casing with a bearing ring which is accommodated movably in a bore in the casing transversely with respect to its axis but non-rotatably. An internally toothed annular gear is rotatably mounted in the bearing ring and meshes with a pinion rotatably mounted in the casing. The bearing ring is pivotable relative to the bore in the casing about a pivot axis parallel to its axis. The pivot axis is so disposed that the ring portion of the bearing ring, which is associated with the engagement-free annular gear region, is moved at least approximately radially towards the pinion axis by the hydraulic pressure forces acting on the annular gear in the pressure chamber.

Abstract: An internally or externally geared pump for conveying fluids lacking or only having insufficient lubricating ability, includes gearwheels moving in an operating chamber of the pump, conveying fluids and being mounted completely in parts formed of a carbon material. Supports are formed from accurately worked lateral walls and a jacket of the operating chamber formed of the carbon material. The jacket surrounds the gearwheels in the radial direction and is likewise constructed as a support. Chambers on the suction side and on the pressure side for fluid supply and fluid removal, which are necessary for the operation of the pump, are molded into side walls of the operating chamber which is formed of carbon.

Abstract: The present invention provides a rotary compressor capable of significantly reducing the loss attributable to mechanical friction. Since an outer rotor 2 is connected via connecting plates 4 to an inner rotor 3, when the outer rotor 2 is rotated by external rotational force, the inner rotor 3 can rotate together with the outer rotor 2 in the same direction. At that time, the rotors 2 and 3 rotate at positions offset relative to each other so that partition pieces 2d on the outer rotor 2 perform circular movement within partition grooves 3b in the inner rotor 3 while turning the connecting plates 4. Thus, the rotors 2 and 3 rotate together, with at least two partition pieces 2d turning all the time along the inner surfaces of the associated partition grooves 3b in a non-contact manner, so that a fluid from an inflow port 1d flows into a space between the rotors 2 and 3 partitioned by the partition pieces 2d and the partition grooves 3b, the fluid being discharged through an outflow port 1e.

Abstract: An oil pump of the type which includes a pump housing formed with an axial bore for support of an input shaft and a cylindrical recess the center of which is eccentrically displaced from the center of the axial bore, an inner rotor formed at its inner periphery with at least a pair of diametrically opposed radial projections for engagement with the input shaft disposed in the axial bore and at its outer periphery with a plurality of external teeth and being mounted on the input shaft within the pump housing for rotation therewith in a condition where opposite side faces of the inner rotor are slidable in contact with a pair of axially opposed internal side faces of the pump housing, and an outer rotor formed at its inner periphery with a plurality of internal teeth for engagement with the external teeth of the inner rotor and being coupled within the cylindrical recess of the pump housing, wherein the diametrically opposed radial projections of the inner rotor are integrally formed at their one ends with an a

Abstract: A bi-directional fluid pump for providing a source of pressurized fluid. The fluid pump includes a gerotor assembly, an inlet valve system, and an outlet valve system which work cooperatively to provide pressurized fluid during two directions of rotation.

Abstract: An in-tank type electric motor fuel pump with a fuel inlet end cap, a fuel outlet cap, a case coaxially joining the end caps to form a pump housing, an electric motor mounted in the housing having a stator with spring-retained permanent field magnets surrounding the motor armature, and a gerotor pump in the housing rotatably driven by the motor armature. An inlet port plate, an outlet port plate and a cam ring sandwiched between the plates form a gerotor pocket axially between the plates, and inner and outer gear rotors are disposed in the pocket with intermeshing teeth defining circumferentially disposed expanding and ensmalling pumping chambers. A pair of alignment and fastening screw pins are the sole hardware for clamping the plates and cam ring in tightly sandwiched relationship and holding the pump unit together in properly axially, radially and angularly oriented component relationship in precision final assembly as an operable gerotor pump.

Abstract: The present invention relates to an oil pump rotor provided with an inner rotor 10 to which n (n is a natural number) outer teeth 11 are formed, an outer rotor 20 to which n+1 inner teeth 21 are formed which engage with each of the outer teeth 11, and a casing 30 in which an intake port 31 for taking up fluid and an expulsion port 32 for expelling fluid are formed, wherein:the outer teeth of inner rotor are formed by alternately combining an epicycloid curve and a hypocycloid curve, the epicycloid curve being generated as an orbit of the point on a circle which rolls along the outside of the base circle without slipping, and the hypocycloid curve being generated as an orbit of a point on a circle which rolls along the inside of the base circle without slipping; the alternately combined curve being generated under the following condition, where E is the diameter of the circle which rolls along the outside of the base circle, and H is the diameter of the circle which rolls along the inside of the base circle:0.

Abstract: An external-rotor-driven lubricating pump comprising a lubricant guidance part including a suction port, an outer wall, a carrier section, a discharge port, a lubricant feed space disposed between the carrier section and the outer wall and connected with the suction port, with a lubricant delivery space disposed between the carrier section and the outer wall and connected with the discharge port, and a pump part including a drive gear, an internally-toothed external rotor, with an externally-toothed internal rotor having one tooth less than the number of teeth on the external rotor, the external rotor and the internal rotor upon meshing pumping the lubricant from the lubricant feed space into the lubricant delivery space, with a shaft supporting the drive gear in the carrier section, the drive gear being fixed to the external rotor, the drive gear forming together with the external rotor the outer closure of the lubricating pump at its pump part end, with the internal rotor being mounted loosely on a collar o

Abstract: The present invention relates to an oil pump rotor for an oil pump provided with an inner rotor 10 to which n (n is a natural number) outer teeth 11 are formed, an outer rotor 20 to which n+1 inner teeth 21 are formed which engage with each of the outer teeth 11, and a casing 30 in which an intake port 31 for taking up fluid and an expulsion port 32 for expelling fluid are formed, wherein:the outer teeth 11 of inner rotor 10 are formed along an envelope described by a generated group of circles having centers positioned on a trochoid curve generated within the limits satisfying the following expression:0.15.ltoreq.n.multidot.R/(p.multidot.D).ltoreq.0.25where D is the diameter of the circle which passes through each of the tips of the outer teeth and R is the radius of the generated circle measured in millimeters, while p is .pi..

Abstract: A gear-type pump having an inner rotor and an outer rotor and in which the outer rotor is supported for rotation by a plurality of roller bearings interposed between a support housing and the outer rotor and in which the inner and outer rotors and the support housing are made of the same material and have essentially the same width dimension so that the thermal contraction of the support housing and the thermal contraction of the inner and outer rotors while pumping super-cooled fluid does not adversely affect the end-clearance between the end plates and the inner and outer rotors to an extent where the efficiency of the pump would differ if it were pumping fluid at a temperature of 70 degrees Fahrenheit.

Abstract: A hydraulic machine with two displacement elements (2,3) rotatably movable relative to one another, namely, a gearwheel (2) and an annular gear (3) of which the number of teeth is one more than the number of teeth (N) of the gearwheel (2), in which machine the tooth form of a least one displacement element (2,3) is defined at least over sections by a trochoid-type curve T=f (RC, E, RT) as the function of a reference circle radius RC, an eccentricity E and a generating circle radius RT. In a machine of that kind, it is desirable for the efficiency and the running behaviour to be improved and for wear to be reduced. To that end, of the parameters (RC, E, RT) determining the function f, at least one parameter varies in the circumferential direction periodically with the period of a tooth pitch (Z).

Abstract: The pump has an inner rotor bounded by an outer peripheral shape which is generated by moving a first circle around a first trochoid. The inner rotor is mounted for rotation about a first axis. The pump also has an outer rotor mounted for rotation about a second axis which is offset from the first axis. The outer rotor is bounded by an inner peripheral shape which is generated by moving a second circle around a second trochoid.

Abstract: A gerotor pump includes a pair of relief ports superimposed on and directly communicating with the pump's inlet and outlet channels, respectively. The relief ports simultaneously communicate with an open mesh pumping chamber so as to provide an intermittent controlled leak from the open mesh pumping chamber. Upon rotation of the gear members of the gerotor pump when the volume in the open mesh pumping chamber is increasing to a maximum volume, fluid in the open mesh pumping chamber vents into the relief port superimposed on and communicating with the outlet channel while continuing to communicate with the relief port superimposed on and communicating with the inlet channel.

Abstract: A rotary engine having an outer rotor on outer rotor bearings and an inner rotor within the outer rotor mounted on inner rotor bearings, the outer rotor axis being offset relative to the inner rotor axis, a housing enclosing the inner and outer rotors, generally radial arms formed on the inner rotor, and recesses defined between them, inwardly projecting lobes defined by the outer rotor, spaced apart, and defining outer rotor chambers, the inner rotor arms extending into the outer rotor chambers, at least around a portion of the rotational path of the rotors, a fresh air intake port for inducting fresh air into the outer rotor chambers in sequence at a predetermined point in the rotational path of the outer rotor, a fuel/air intake port for inducting burning fuel/air into the outer rotor chambers in sequence at a second predetermined point, and an exhaust port for exhausting gases from the outer rotor chambers in sequence at a third predetermined point.

Abstract: Along a peripheral wall surface of a pump housing at a closure portion where a working fluid in a volume chamber defined by engagement of an inner rotor and an outer rotor, is enclosed, a liquid pressure is relieved by the liquid pressure relieving groove for relieving a liquid pressure of the working fluid from the volume chamber to a sliding gap along an outer peripheral surface of the outer rotor.

Abstract: A hydraulic motor that provides an improved sealing configuration for sealing a shaft with respect to a housing of an internal gear motor or pump of the type commonly known as a gerotor. The hydraulic motor provides a housing having an output end and an input end with an opening extending therebetween. A gerotor is connected to the input end of the housing, and a cover is connected to and covers the gerotor while also receiving and rotatably supporting an end of the shaft. An inlet port and an outlet port are provided in the cover for communicating hydraulic fluid to and from the gerotor. A large roller bearing is coupled to the shaft and disposed within the opening of the housing to rotatably support the shaft. For high pressure applications, a pair of conventional mechanical face seals are coupled to the shaft and disposed within the opening of the housing. A third conventional lip seal may also be utilized as an added level of sealing the shaft with respect to the housing.

Abstract: A rotary pump (10) of the type having inner and outer rotary components (32, 30) which rotate in the same direction at the same speed, the inner rotary component (32) being located within the outer rotary component (30), and in which the outer rotary component (30) has an annular wall (44), abutments (46) and recesses (50) between the abutments (46), and contact bodies (48) formed on the abutments (46) and being shaped as a major segment of an ellipse; and in which the inner rotary component (32) has an inner body (60) with abutments (64) located within respective outer recesses (50), and receiving the outer wall abutments (46) and contact bodies (48), the outer component (30) having a rotary axis, located along its central axis, a drive shaft (36) connected to the inner body (32) and located along its central axis, the outer and inner axes being parallel to and spaced from one another so that the inner component (32) is located offset from the center of the outer component (30), the inner body recess surface

Abstract: A hydraulic machine is disclosed, with an annular gear with internal teeth and, eccentrically mounted in the annular gear, a gearwheel with external teeth which engage with the internal teeth, the internal teeth comprising one more tooth than the external teeth and the contour of the external teeth being formed by an envelope of a system of generating circles, the midpoints of which lie on a trochoid which, as a rolling circle rolls without slipping on a base circle, can be generated by the movement of a point lying on a radial ray of the rolling circle co-rotating with the rolling circle. A method of producing the contour of a rear wheel of such a machine is also disclosed. In such a machine it is desirable to realize a satisfactory inner seal and low Hertzian stresses. To that end, the spacing of the point from the midpoint of the rolling circle is larger than the radius of the rolling circle.

Abstract: A hydraulic machine is disclosed, with a gearwheel, which has a midpoint (6) and a predetermined number of external teeth, and an annular gear, which has a midpoint (7) offset by an eccentricity (E) with respect to the midpoint (6) of the gearwheel and a number of internal teeth which exceeds by one the number of external teeth, the gearwheel and annular gear orbiting and/or rotating relative to one another and at least the form of the external teeth being created using a set of circles (30, 30'; 35, 35') lying with their midpoints (P1-P6; P1'-P6') on a trochoid (36, 37). It is desirable for the efficiency, service life and noise properties of such a machine to be improved. To that end, at least two trochoids (36, 37), displaced relative to one another in the circumferential direction, are provided for generating a tooth profile, the rolling circles (28, 33) of which and the base circles (27, 32) of which differ from one another.

Abstract: Disclosed is a fluid delivery supply unit having an internal gear pump as a pump unit, with a bearing race in which a driven inner gear is arranged on a bearing journal and the inner gear rotates with it by way of toothing engagement with an outer gear arranged between the inner gear and the bearing race, and the inner gear has one tooth fewer than the outer gear so that a pumping action is produced. A low noise level, resistance to corrosion, and a reduced weight, are obtained by forming parts of the internal gear pump, such as the bearing race, inner gear or outer gear, of a ceramic material.

Abstract: A sickleless internal gear pump with an internally toothed ring gear and a pinion meshing with the ring gear, the two fitted rotatably in a common casing. The ring gear includes radial conduits for the medium to be pumped and elements which are radially movably fitted in grooves in the tooth heads of the ring gear or pinion. The sealing elements slide on the opposing tooth head of the pinion or ring gear and include control spaces on which pressure is applied from the rear. For pressure application in the control spaces there is machined at least one control slot in the area of the pressure buildup zone, on at least one side of the part of the casing which laterally bounds the ring gear and pinion.

Abstract: A rotary pump for volatile hydrocarbon fuels for use in a fuel system of an internal combustion engine of an automotive vehicle. A pulsation chamber allows purging of fuel vapor from the pump and dampens expansion and contraction of the fuel and vapor due to pressure pulses created during the pumping cycle thereby greatly reducing audible noise of the operating pump. The pulsation chamber has an axial passage with an outlet for returning fuel and vapor from the pulsation chamber to the fuel supply.

Abstract: A compact gerotor pump having reduced axial dimension has an external fixed pump body in which a rotor and annulus set is housed. A drive shaft is provided that is neither fixed nor journalled directly by the pump body. The shaft is secured to the rotor within the body and extends through an opening in an end wall of the body and is secured to the hub of an external drive gear that is journalled by the housing for driven rotation of the drive gear, shaft, and rotor relative to the pump body.

Abstract: An improved system for lubricating the gears and bearings in a vehicle transmission is provided including an improved gerotor pump mounted on the interior of the transmission housing. The gerotor pump includes an inner pump element and an outer pump element. One end of the outer element is provided with a radially inwardly extending portion which extends over the end of the inner element. This end of the outer element also includes a radially outwardly extending toothed portion which meshes with and is driven by one of the countershaft gears of the transmission. The inner and outer elements are both piloted on a flanged nut and pilot pin assembly which is secured to an interior wall of the transmission housing by a threaded stud. The gerotor pump of the invention thus eliminates the need for a pump housing and permits the use of a higher displacement set of gerotor elements in a given amount of space.

Abstract: In an oil pump having an inner rotor and an outer rotor supported in a housing, pressure in a pumping chamber whose volume is at maximum presses the inner rotor inwardly and the outer rotor outwardly. An oil groove which communicates with a discharge port via a lubricating groove is formed in an inner surface of the housing at the circumferential position of the pumping chamber whose volume is at maximum. The oil groove has axial sealing surfaces.

Abstract: A gear pump including a body, a port plate, a pair of gerotor-type rotors, one rotor being connected to a shaft, and a retaining assembly operative on the port plate to rotatably couple it to the body. The retaining assembly permits adjustment of axially oriented inlet and outlet ports disposed in the port plate to vary fluid flow from the pump. Both manually and automatically adjustable retaining assemblies are disclosed.

Abstract: A roller gerotor device is disclosed including an outer rotor (39) and an inner rotor (31), and a plurality of rollers (37) serving as teeth. The device includes a housing means (11,45,47) defining a first wear surface (67) disposed axially adjacent first axial end surfaces (55,63) of the rotors. The first wear surface cooperates with one of the rotors to define an annular fluid passage (83) and a plurality of fluid grooves communicating with the passage (83) and extending radially outward. At least a terminal portion of each of the grooves (87) is adjacent an axial end surface (59) of each roller member (37) as the rotors rotate. Each of the terminal portions (95) becomes progressively shallower in the direction of rotation of the rotors, thus building up fluid pressure in the fluid groove (87) to prevent gouging or galling of the roller end surface against the adjacent wear surface (67).

Abstract: An involute gearset formed of at least two meshing gear wheels the teeth of which have flanks formed of different curves including an involute in the central region, an arcuate region adjoining the involute, and a straight line segment which intersects the end face of a respective tooth and tangentially passes into the arcuate region.

Abstract: In an internal gear pump, which can also be constructed as pump with suction control, to reduce the undesired cavitation effects in the pressure region and to permit the oil to flow off from the diminishing displacement cells between the teeth of the gears, and impedance-controlled overflow passage is provided, the openings of which towards the moving displacement cells are alternately opened and closed by the teeth of at least one of the gears.

Abstract: The invention relates to a gear pump for oil for an internal-combustion engine, in particular for motor vehicles, comprising a pump housing mounted on the motor and an outer rotor which is arranged in the pump housing, an inner rotor additionally being arranged within the outer rotor or within the pump housing and at least one suction and/or at least one pressure passage being provided in the pump housing, a drive further being present; the pump according to the invention is integrated in a drive wheel or guide pulley of the internal-combustion engine and the outer rotor or the outer rotors are driven by the drive wheel or the guide pulley.

Abstract: In a gear-type machine, in particular in a ring gear pump with internally toothed ring gear meshing with a pinion having only one tooth less, for reducing the noise the pinion teeth are only half as wide as the internally toothed ring gear teeth and the cycloids are flattened in order to ensure adequate free passage of the teeth heads opposite the point of deepest teeth engagement in spite of minimum clearance.

Abstract: An aggregate for feeding fuel from a supply tank to an internal combustion engine of a motor vehicle has a feeding pump having two end walls forming a pump chamber with a suction opening and a pressure opening and a feed element rotatable in the pump chamber so as to supply fuel from the suction opening to the pressure opening. At least one of the end walls is provided with a groove-shaped unloading passage in a region between an end surface of the feeding element and a sealing surface of the one end wall and communicating through a further opening the pump chamber with a low pressure region. The suction opening has an end facing in a rotary direction of the feeding element. The unloading passage is located near the end of the suction opening.

Abstract: A rotor-type oil pump for sucking and discharging oil to be supplied to a variety of oil-requiring parts of an automotive engine. The oil pump comprises a generally annular outer rotor which is rotatably disposed in a pump casing. A generally annular inner rotor is disposed eccentrically inside the outer rotor and has an external gear which is partly in mesh with the internal gear of the outer rotor. The outer rotor is designed such that stress at the tooth base section of the internal gear is generally equal to stress at the tooth base section of the external gear of the inner rotor in their dynamic condition, thereby reducing the thickness of the tooth base section of the outer rotor.

Abstract: The invention relates to a sickleless internal gear pump with an internal ring gear and a pinion meshing with the ring gear. The ring gear and pinion are rotatably mounted in a common housing part having an axial expanse corresponding to the width of the teeth of the ring gear and the pinion. The housing features a suction port and a pressure port. The ring gear features radial ports for the fluid medium to be pumped. Disposed in the pressure side region of the housing, opposite the rotating gearing parts of the ring gear and the pinion, is an axially movable axial disk exerting a force on the rotating gearing parts dependent on an axial pressure derived from the working pressure. The axially movable disk provides axial sealing by compensating for the gap between it and the fixed housing.

Abstract: An aggregate for feeding fuel from a supply tank to the internal combustion engine of a motor vehicle, has a pump chamber with a suction opening for receiving fuel and a pressure opening for supplying a fuel and a feeding element rotating in the pump chamber and feeding fuel from the suction opening to the pressure opening. At least one of the chamber end walls in a region of a sealing surface formed between an end surface of the feeding element and one of the chamber walls has an opening which leads to an unloading space, and the opening as considered in a rotary direction of the feeding element is located near one edge which limits the suction opening, and has a radial extension which is at least equal to a radial extension of the suction opening.

Abstract: There is disclosed a trochoid pump in which a friction between a rotor and its support portion is reduced, thereby reducing a drive torque and wear of these parts. An inner rotor of the trochoid-type fuel pump is rotatably supported by a bushing through a bearing. An outer rotor is rotatably received in an inner periphery of a spacer. A first groove is formed in a portion of the outer periphery of the bushing disposed close to a discharge port, and a discharge fuel is introduced into this groove. A second groove is formed in a portion of the inner periphery of the spacer disposed close to the discharge port, and the discharge fuel is introduced into this groove. Although the inner rotor is urged toward the bushing by the fuel pressure of the discharge port, the urging force to urge the inner rotor toward the bushing is weakened by the discharge fuel introduced into the first groove, thereby reducing a friction.

Abstract: A rotary machine, such as a horizontally oriented scroll type refrigerant compressor is disclosed. The compressor includes a compressor housing, an inner block fixedly disposed within the compressor housing, a drive shaft extending substantially in the horizontal direction, and a driven mechanism, such as a compression mechanism operatively connected to one end of the drive shaft. The drive shaft is rotatably supported by the inner block and the compressor housing. A shielding element, such as an annular cylindrical member is fixedly held between the inner block and the compressor housing to prevent the drive shaft from passing through an oil sump of the housing. An internal lubrication oil pump is formed by the elements which are associated with the drive shaft, and is operated by virtue of the rotational motion of the drive shaft in order to supply the lubrication oil from the oil sump to the frictional surfaces of the internal component parts of the compressor.

Abstract: An oil pump comprises a housing, a cover, an inner gear having external teeth and a recess, and an outer gear having internal teeth engaged with the external teeth of the inner gear. The housing or the cover includes an engagement protrusion to be engaged with the recess of the inner gear for supporting the inner gear during assembly.

Abstract: A gear pump in which a gear is secured to a shaft by a press fit and by a key which fits into a slot in the shaft. The key includes radially projecting ears which fit into keyways in the bore of the gear, the keyways having bottoms facing axially toward the bottom of the slot. A hot upset at the free end of the shaft clamps the key axially between the bottom of the slot and the bottom of the keyways. When the shaft/gear/key subassembly is assembled with the body and the end plate of the pump, the gear retention elements described above coact to positively prevent the shaft from being pulled out of the body and from being thrust inwardly into contact with the end plate.

Abstract: A hydraulic pump in the form of an oil pump for a vehicle engine has both its pinion, which is driven by the engine's crankshaft, and a ring-gear, which cooperates with the pinion, incorporated in an end-cover fastened to the end of the engine block. A cap is inserted in a collar on the side of the end-cover facing away from the engine and is only held in position there by means of a locking ring, which engages with a groove in the collar and presses the cap toward the engine. Outside the oil pump, a partly socket-shaped belt pulley is mounted on the crankshaft and its socket-shaped portion substantially grips the collar. Fitting and removal are thus simplified and engine overall length reduced. Simplified sealing also reduces oil leakage risks.

Abstract: An internal gear pump having the following characteristics: an internal gear; a pinion which meshes with the internal gear and is mounted eccentrically with regard to the internal gear; a shaft supporting the pinion; a central ring-shaped housing part encompassing the internal gear and pinion and comprising a suction socket as well as a pressure socket; on both sides of the central housing part, a ring-shaped housing intermediate part each by which the shaft is supported; a cutout provided in each intermediate part and extending bow-shaped in peripheral direction; a web is provided which bridges the sole cutout; and the web is located at least approximately in that area of the pinion which diametrically opposes the pressure socket.

Abstract: A magnetic drive mechanism and cooling system for driving a rotary pump having a magnetic rotary drive member with a recess therein. A magnetic rotary driven member is located in the recess of the drive member. A container is located between the drive member and the driven member for preventing the escape of cooling fluids circulated therein. Inlet and outlet fluid passages extend through the housing of the drive mechanism to the fluid containment area. Another fluid passage extends from the fluid containment area into the chamber of the pump. A cooling fluid is pumped through the fluid passages at a higher pressure than the pressure of the pumped fluid within the pump to prevent flow of the pumped fluid into the fluid passages and containment area of the drive mechanism to avoid contamination thereof while the cooling fluid is circulated to cool the driven member.

Abstract: A pump comprises an outer rotor and an inner rotor. A plurality of pressure chambers are defined between the outer rotor and the inner rotor to cause fluid to be sucked from a suction port and discharged to a discharge port by the movement of these pressure chambers with changing their volumes. A pressure relief passage is opened between the discharge port and the suction port and communicated directly with a fuel tank provided outside the pump. This causes the pressure in the pressure chamber to be reduced before the pressure chamber is communicated with the suction port. In consequence, it is possible to prevent the fuel of discharge pressure in the pressure chamber from being brought in the suction port, thereby preventing the generation of vapor caused due to vacuum boiling and the reduction of discharge rate.

Abstract: A method of setting up the required running tolerances in a gerotor pump having annulus and rotor meshed together and located in a body comprises pressing a cover plate (FIG. 1) or equivalent as an interference fit into the body and then allowing it to relax and recover elastically to set up the required tolerances at axial ends of the gerotor set.

Abstract: An oil pump comprises a pump casing, a crankshaft, an inner rotor mounted on the crankshaft, an outer rotor, an intake chamber, and a discharge chamber. The inner rotor has outwardly projecting teeth which engage with inwardly projecting teeth of the outer rotor for rotating the outer rotor for transferring oil from the intake chamber to the discharge chamber. A stopper is provided which contacts edge portions of the teeth of the inner and outer rotors respectively to prevent oil in a space between the teeth from leaking.

Abstract: An internal gear pump is disclosed having at least two essentially identical internal gears and a pinion meshing with the internal gears, all being rotatably disposed in a housing, the axial dimension of which is substantially equal to the width of the gear and pinion teeth. The housing includes a suction connection and a pressure connection. The internal gears have radial through-bores for the medium to be pumped. A support is provided at the contacting surfaces of the internal gears near the pressure connection.