Abstract: The invention relates to a rotor for a positive displacement rotary pump. The rotor comprises a hub with an aperture and a center axis through aperture and at least 2 lobes radially extending from hub and in a direction essentially perpendicular to the axis of hub. The rotor comprises a core of a first polymer material and a cover of a second polymer material, which second polymer material has a hardness which is lower than the first polymer material. The first and the second polymer materials are connected to each other. The hub or the major part of the hub is preferably provided by the core, whereas at least a part of the lobes is provided by the cover. The invention also relates to a method of providing the rotor and a pump comprising the rotor.

Abstract: An improved positive displacement pump provides improved wear characteristics. Specifically, rotor pads are provided on faces relative to an internal portion of the rotor housing as it relates to an end wall and a rear side of a cover plate. The rotor pads preferably have at least one of anti-galling and/or anti-friction or anti-wear characteristics thereby providing improvements over the prior art. A central member is preferably provided so that pad replacement may be relatively easily performed in the field in clean in place operations.

Abstract: According to an aspect of the present invention, an electric pump includes: a housing; an outer rotor; an inner rotor; a base member facing one side surface of the outer rotor and one side surface of the inner rotor; a side plate member, having a facing surface facing the other side surface of the outer rotor and the other side surface of the inner rotor and a non-facing surface opposed to the facing surface; a shaft; a suction port; a discharge port; a negative pressure applied region; a positive pressure applied region; and a relief valve, discharging the fluid from the positive pressure applied region to a non-facing surface side of the side plate member when a pressure applied at the positive pressure applied region exceeds a predetermined value.

Abstract: An improved positive displacement rotary pump apparatus and method is provided. The pump may include a front cover, a rotor body forming a chamber with the front cover, a gear case supporting a pair of hollow drive shafts, and a pair of rotors disposed in the chambers and each detachably mounted to one end of a respective hollow drive shaft via a stud that extends from the rotor through the hollow shaft to a fastener.

Abstract: An intended purpose of this invention is to realize a gear pump suitable for delivery of high-pressure and high-viscosity fluids by using helical gears meshing with each other. For this purpose, the gear pump includes introduction paths for introducing the fluid from a discharge side toward shaft end sides of gear shafts to apply shaft ends of the gear shafts with fluid pressures counterbalancing axial thrusts produced by the helical gears.

Abstract: A gear pump has a pump housing formed with a gear receiving recess, a pump cover coupled with the pump housing to cover the gear receiving recess, a hydraulic passage that uses the gear receiving recess as a passage part thereof, and annular inner and outer gears operatively installed in the gear receiving recess. The inner and outer gears are of a bevel type and meshed with each other in such a manner as to bias the inner gear in a direction to reduce the thickness of the passage part when the inner gear is rotated while turning the outer gear therearound.

Abstract: A vane pump can effectively utilize the total quantity of a working fluid delivered from a vane section. The pump can be used for fluid pressure operated equipment requiring a high flow rate, does not create torque loss due to a throttle valve, and can prevent the occurrence of cavitation caused by a shortage of suction. The vane pump pressurizes and delivers a working fluid through a vane section. A returning working fluid flowing through a return port is throttled and accelerated by a throttle valve, and a working fluid sent from a suction port is attracted by the accelerated returning working fluid so that the returning working fluid and the working fluid sent from a tank are sent into the vane section.

Abstract: In a gear pump equipped with a pump assembly formed from a driving gear supported by a driving shaft, a driven gear supported by a driven shaft, a pair of side plates disposed at both sides in an axial direction of driving and driven shafts, and a seal block that seals tips of the gears and forms a first fluid chamber by installation onto the side plates, and a casing that houses the pump assembly and forms a second fluid chamber therein, ribs are provided for at least one member of the side plates or the seal block, and fluid tightness between the first and second fluid chambers is secured by exerting pressure between the side plates and seal block and additionally plastically deforming the ribs. By this, it is possible to provide the gear pump which is capable of achieving improvement of the seal integrity while reducing the parts count.

Abstract: Rotary seals in a telescoping gear pump/motor a feature that allows the seal to shift radially relative to other components while maintaining the seal integrity and without compromising the function of the bearings or the bushings needed to bear the load.

Abstract: A motor and a method of operating the motor are described. The motor may have a female rotor shaft having mounted thereon a female compression rotor, a female power rotor, and a spur gear. The motor may also have a male rotor shaft having mounted thereon a male compression rotor, a male power rotor and a power rotor gear. A housing containing the foregoing may have a front housing plate, a compression rotor case, an isolator plate, a power rotor case, a rear housing plate, and a gear cover adjacent the rear housing plate. The various female and male rotors are engaged with one another within the housing.

Abstract: The invention relates to oil-flooded screw compressors having a male rotor and female rotor each featuring preferably a ratio of male-to-female rotor lobes of 4:6, 5:6 or 5:7. In order to decrease the bearing load at higher working pressures, the profile sections of the rotors are shortened, and an intermediate plate is appropriately arranged in the free space formed.

Abstract: Besides the conventional pump timing in rotary hydraulic devices, a series of constant and variable restrictions have been applied to condition the pressurized flow used to internally precompress the volume or volumes to be displaced. This multiple staged orifices feature reduces the outgassing associated with the pressurized flow passing through a single restriction, such as a metering groove. The pressurization of the outgassed fluid will cause noise and erosive wear of the pump internal containment surfaces.

Abstract: A gear pump arrangement comprising a pair of intermeshing gears (16, 18) located between bearing blocks (24) and rotatable to pump fluid from an inlet (12) to an outlet (14), wherein at least one of the bearing blocks (24) comprises a body (28) formed with a recess (32) within which an insert (34) is located, the recess (32) and insert (34) being shaped so as to be of smaller dimensions at a bearing surface (30) of the bearing block (24) than at a point remote therefrom.

Abstract: A variable capacity pump/motor has a meshing internal and external gear set disposed between an upper mandrel and a lower mandrel, each including a flange extending towards the gears to divide a pump/motor chamber into suction and discharge chambers. The inner gear is fixed and the external gear is axially moveable with respect thereto. The external gear and the upper mandrel move in response to changing pressures in the casing, allowing the motor to vary displacement and the pump to vary its output based on supplied fluid pressure or based on the speed of the prime mover. An external configuration includes a pair of meshing gears mounted on separate shafts in a casing. One gear is fixed and the other is axially moveable with respect thereto and moves in response to changing pressures in the casing. Each of the gears is sealed by a seal/bushing on a free end thereof.

Abstract: In a gas compressor, housing heads are disposed to define an internal space with a housing, and two rotors housed in the internal space are rotatable to form in the internal space a compression chamber. The housing has an inner wall surface opposed to at least outer peripheral surfaces of the two rotors, and the housing heads are provided in correspondence to the respective rotors. One end portion of a rotary shaft of each rotor is supported by the housing, and other end portion of the rotary shaft of each rotor is supported by the housing heads. The housing heads have a first outer peripheral portion corresponding to the inner wall surface of the housing, and a second outer peripheral portion larger than the first outer peripheral portion. Furthermore, the first outer peripheral portion of the housing heads is fitted onto the inner wall surface of the housing.

Abstract: A pump, in particular a hydraulic pump for a power steering system, has a housing. The pump is a prefabricated structural unit in which the end faces of the housing are closed by a flange and by a cover, respectively. The flange and the cover are braced against each other by at least one holding part.

Abstract: A side face of a pump gear is formed into a stepped face such that an annular region extending radially from a diameter which is smaller than a dedendum circle diameter of the pump gear and larger than the outer diameter of a pump gear bearing to the addendum circle diameter of the pump gear is recessed by a certain depth to increase the side gap in the recessed annular region. Therefore, the side gap in the recessed annular region is larger than a side gap in a region between the diameter smaller than the dedendum circle diameter of the pump gear and larger than the outer diameter of the pump gear bearing to the outer diameter of the pump gear bearing.

Abstract: The curvature of a circular arc constituted by a side of a suction groove is made larger than that of a circular arc constituted by a side of a discharge groove. Thus, when the suction groove and the discharge groove are viewed in the axial direction of a drive shaft, the distance between the suction groove and the discharge groove in the radial direction of a rotary portion is short in a region intersecting with a line W perpendicular to a centerline, and increases in accordance with a decrease in distance from containment portions. It is therefore possible to ensure a sufficient distance between the discharge and suction grooves and enhance a total fluid pressure generated therebetween, and the contact surface pressure that is necessitated by a second side plate to obtain a press-back force when being in contact with an outer rotor and an inner rotor is reduced.

Abstract: An oil pump is provided which includes a cam ring made of a material having a first line expansion coefficient, a pump element rotatably disposed in the cam ring and smaller in an axial length than the cam ring, a first housing member disposed on one of axially opposite sides of the cam ring and made of a material having a second line expansion coefficient larger than the first line expansion coefficient, and a second housing member disposed on the other of the axially opposite sides of the cam ring and made of a material having a third line expansion coefficient than the first line expansion coefficient.

Abstract: A hydraulic vane pump includes a plurality of members forming a recession and an orifice in fluid communication with one another and with rotating vane cells at an inlet sector of the pump. Air entrained in the vane cells is exhausted through the recession and the orifice prior to fluid passing from the inlet sector to a discharge sector, thereby increasing pump capacity and decreasing cavitation noise. A method of pumping fluid in a vane pump to decrease cavitation noise is also provided.

Abstract: A body bore 2 formed in a body 1 is closed with a cover 9, as well as a cam ring 4 is incorporated into the body bore 2, and a rotor 6 is arranged inside the cam ring 4. Vanes 7 move in and out along an inner surface of the cam ring 4 with rotation of the rotor 6. An iron reinforcing plate 8 is interposed inside the body bore 2 between the cam ring 4 and the cover 9.

Abstract: A pressure compensation mechanism for a gerotor motor is disclosed, which mechanism includes a shuttle valve that selectively interconnects either port to a single pressure chamber and thus to compensate for any pressure-induced imbalances in the device.

Abstract: Improved gerotor pumps comprising laterally constrained floating rings, thereby providing an orthogonal degree-of-freedom and allowing gerotor sets positioned therein to establish their own preferred mesh orientation, and additionally wherein the outer rotor of the gerotor set is forcibly positioned against the inner rotor of the gerotor set at the gerotor set's in-mesh position whereat there is little relative motion between the inner and outer rotors, thereby resulting in a substantially friction- and wear-free meshing action of the gerotor set.

Abstract: A rotary positive displacement hydraulic machine includes a housing defining two mutually intersecting parallel working chambers having a low pressure inlet side and a high pressure outlet side. Two meshing rotors are mounted for rotation in the two chambers, respectively. Bearing supports at opposite ends of the chambers, support bearings in which the rotors are journalled for rotation. At least one end of the housing is closed by an end cover. The end cover and adjacent housing end have at least one elongate recess on each side of the working chambers. The end cover recesses are alignable with the housing recesses. There is at least one keying element in each pair of aligned recesses so that the open end of the housing is supported against relative movement by differential fluid pressure in the chambers in a direction transverse to a plane containing the axes of rotation of the meshing rotors.

Abstract: A rotary piston pump for fluids, wherein the ends of the housing are configured so as to provide reduced pressure differentials between opposite sides of the rotor end disks.

Abstract: A variable capacity pump/motor has a meshing internal and external gear set disposed between an upper mandrel and a lower mandrel, each including a flange extending towards the gears to divide a pump/motor chamber into suction and discharge chambers. The outer gear is fixed and the internal gear is axially moveable with respect thereto. The inner gear and the upper mandrel move in response to changing pressures in the casing, allowing the motor to vary displacement and the pump to vary its output based on supplied fluid pressure or based on the speed of the prime mover. An external configuration includes a pair of meshing gears mounted on separate shafts in a casing. One gear is fixed and the other is axially moveable with respect thereto and moves in response to changing pressures in the casing. Each of the gears is sealed by a seal/bushing on a free end thereof.

Abstract: The invention concerns a gear pump comprising a pump body (2) closed with a cover (3) forming a cavity wherein is provided a drive pinion (4) capable of being driven in rotation by a drive shaft (1) whereto it is fixed, a driven pinion (5) whereof the teeth co-operate with the drive pinion (4) teeth so as to be driven in rotation thereby and two end shields (8) arranged on either side of the driven pinion (5) penetrating into a cavity (10) provided therefor in the pump body (2) and the cover (3) respectively, means being provided for exerting pressure on the outer surface of the end shields. In order to prevent the cover from being deformed under the effect of the pressure thereby creating a leakage zone between the delivery zone and the suction zone, the end shields each consist of a disc (8) integral with one end of the driven pinion (5), the discs (8) and the driven pinion (5) being concentric, the discs (8) covering the teeth of the driven pinion (5).

Abstract: In a vane pump, a rotor chamber is defined within a housing that includes a ring and first and second plates. An inlet is communicated with the rotor chamber through an intake groove, and an outlet is communicated with the rotor chamber through a discharge groove. A rotor, which has a plurality of radially reciprocable vanes, is rotatably received in the rotor chamber, and a plurality of volume variable pump chambers is defined by the vanes between an inner peripheral wall surface of the housing and an outer peripheral surface of the rotor. The discharge groove includes a first end and a second end, and the second end is positioned away from the first end in the rotational direction of the rotor. The outlet extends directly from the second end of the discharge groove.

Abstract: A bearing assembly (20) for a pump (12), e.g., an internal or external gear pump includes a journal bearing block (20) having a length, a width, and an axial centerline (CL?) passing through a center of the journal bearing block (20) with respect to the length. The journal bearing block (20) includes at least two journal bearing bores (21), the journal bearing bores (21) each having a center (C), wherein a bearing bore centerline (CL) extends between the centers (C) of the journal bearing bores (21) and in parallel with the bearing bore centerline (CL). The bearing bore centerline (CL) is offset with respect to the width of the journal bearing block (20) and the axial centerline (CL?). The bearing assembly (20) is particularly applicable to gear pumps, such as external gear pumps for fuel applications.

Abstract: In a rotary pump for a braking apparatus, a discharge trench is formed on an axial direction end surface of a second side plate that forms a mechanical seal. As a result, rotors are pressed back toward a side of a first side plate by a discharge pressure of brake fluid channeled to the discharge trench. Accordingly, a force pressing the rotors toward the second side plate is reduced and frictional resistance is reduced.

Abstract: A hydraulic motor comprising a housing having a fluid inlet. A fluid outlet and a cavity there between, a pair of intermeshing gear elements rotatable in the housing about mutually parallel axes. Each of the gear elements having a set of gear teeth disposed about the periphery of the element and a support shaft extending from oppositely directed end faces of the set of gear teeth. A bearing assembly located on opposite sides of the cavity in said housing to support the shafts for rotation about respective ones of the axes. Each of the bearing assemblies having a sealing face overlying the end faces and biased into engage with the end faced by a pressure compensating seal located between the bearing and the housing. The sealing face having a channel extending partially about the spindle and in fluid communication with the inlet to introduce fluid under pressure between the faces.

Abstract: A positive-displacement rotary pump comprising a pair of meshing gears (13, 14) or rotors, consisting of a driving gear and a driven gear, contained in a shell (10) having an output opening and an intake opening for a fluid. The gears (13, 14) include shafts (23, 24) which are supported by bushings (15a, 15b) having two faces (17a, 17b) which are subjected, in use, to pressures which bring about an axial load on the bushing itself, wherein the resultant of the axial loads (S?, S?) on the two bushings has a predetermined direction so as to move the bushings (15a, 15b) and the gears (13, 14) as a whole into close abutment with a predetermined reference plane (VI—VI).

Abstract: A sanitary pump with gear shaft bearing blocks in opposed cylindrical portions of a pump body bore, blocks constituting hand removable structural pump ends. Gear shaft bearings extending completely through blocks for easy cleaning, sealed by O-rings and clamp plates. Oval gear cavity bore between cylindrical portions of body bore extends only length of largest of interchangeable gears. Seals at end of gear cavity eliminate entrapment zones. Minimal intrusion of bearing blocks into gear cavity allows large operating temperature range. Shaft seals are contained in a hand removable cartridge. Complete pump disassembly by one manually operated clamp. Gear shaft diameters differ assuring correct assembly. Mount receives pump, tie rods sealing pump and securing to mount. Mount allows pump removal without changing pump-drive alignment. Pin and groove engagement of pump to mount allows 90° interval pump ports orientation. Pump displacement is altered with interchangeable gears and drive end bearing blocks.

Abstract: A rotary fluid pressure device having a housing member, a manifold assembly, a gerotor set, a channeling plate and an end plate. The gerotor set having a stator member with at least one axial fluid path extending therethrough and a rotor member, disposed within said stator member, having an axial end surface with a recess, and a plurality of axially extending through holes for fluid flow therethrough adapted for hydraulically axially balancing its axial ends relative to the stator. The channeling plate having a first and second fluid passage extending therethrough, and a plurality of through holes. Means for routing the high pressure fluid from the housing member through the gerotor set, through the channeling plate first and second fluid passages, into and subsequently out of a cavity between the channeling plate and the end plate and into the rotor recess to overbalance the rotor towards the manifold assembly.

Abstract: A bearing assembly (20) for a pump (12), e.g., an internal or external gear pump includes a journal bearing block (20) having a length, a width, and an axial centerline (CL′) passing through a center of the journal bearing block (20) with respect to the length. The journal bearing block (20) includes at least two journal bearing bores (21), the journal bearing bores (21) each having a center (C), wherein a bearing bore centerline (CL) extends between the centers (C) of the journal bearing bores (21) and in parallel with the bearing bore centerline (CL). The bearing bore centerline (CL) is offset with respect to the width of the journal bearing block (20) and the axial centerline (CL′). The bearing assembly (20) is particularly applicable to gear pumps, such as external gear pumps for fuel applications.

Abstract: A hydraulic rotating motor for the driving mechanism of tools, especially also for the driving mechanism of electricity consumers, such as electromagnets, as well as a vehicle, a machine/a crane with such a rotating motor, is described. The rotating motor preferably has revolving working pressure chambers 27, which are acted upon by hydraulic fluid for producing a rotational movement, which is transferred to a driven shaft 26. In the case of the rotating motor, electricity is supplied to the consumer, through a lead 19, 20, which is passed from the outside into a stationary head 9, through the interior of the rotating motor to the consumer. For the vehicle with the inventive rotating motor, leads supplying electricity are passed protected within a radial arm to the head 9 of the rotating motor and, from there, through the interior of the rotating motor to the actual consumer of electricity, so that the cables 19, 20 are protected towards the outside until they are passed on to the consumer.

Abstract: A rotary vane device for hydraulic transmission of mechanical energy with industrial scale measures of power and rotational velocity. The device offers high measures of both volumetric efficiency and rotational velocity and hence substantial measures of functional excellence in terms of power density and functional efficiency. Additionally the device functions without the use of reciprocating primary components and for this reason potentially offers substantial measures of excellence in terms of enhanced operational reliability and relatively low measures of radiated mechanical noise and vibration.

Abstract: A positive-displacement rotary pump comprising a pair of meshing gears (13, 14) or rotors, consisting of a driving gear and a driven gear, contained in a shell (10) having an output opening and an intake opening for a fluid. The gears (13, 14) comprise shafts (23, 24) which are supported by bushings (15a, 15b) having two faces (17a, 17b) which are subjected, in use, to pressures which bring about an axial load on the bushing itself, characterized in that the resultant of the axial loads (S′, S″) on the two bushings has a predetermined direction so as to move the bushings (15a, 15b) and the gears (13, 14) as a whole into close abutment with a predetermined reference plane (VI-VI).

Abstract: A bearing arrangement for a gear pump comprises first and second separate bearing blocks each having a respective block housing. The first and second bearing blocks together defining an axially directed bearing surface including a bridge region formed from an erosion resistant material which acts to separate inlet and outlet ports of the pump and a second region formed from a reduced friction material. The bridge region is defined by first and second insert members cast within respective ones of the block housings. The first and second bearing blocks are arranged such that respective surfaces of the first and second insert members mate with one another, and the first and second insert members are arranged such that the bridge region of the bearing surface is flush with the second region.

Abstract: In a vane pump, a rotor chamber is defined within a housing that includes a ring and first and second plates. An inlet is communicated with the rotor chamber through an intake groove, and an outlet is communicated with the rotor chamber through a discharge groove. A rotor, which has a plurality of radially reciprocable vanes, is rotatably received in the rotor chamber, and a plurality of volume variable pump chambers is defined by the vanes between an inner peripheral wall surface of the housing and an outer peripheral surface of the rotor. The discharge groove includes a first end and a second end, and the second end is positioned away from the first end in the rotational direction of the rotor. The outlet extends directly from the second end of the discharge groove.

Abstract: The problem of aligning the drive shaft of a pressure clamped pump with the output shaft of a drive motor in a hydraulic apparatus is solved through the use of pressure clamped pump having a housing adapted for installation into a cavity and a drive shaft coincident with the center of the housing. The hydraulic apparatus may include piloting features configured to facilitate alignment of the pump drive shaft with the output shaft of a motor used to drive the pump. The pump may include elements for retaining the drive shaft within the pump, and may also include a larger and less restricted inlet than could be achieved in prior pressure clamped pumps. The pump may include pumping means in the form of a gear pump having a single primary gear driving a single secondary gear. The pumping means may alternatively be a gear pump having a single primary gear driving two or more secondary gears.

Abstract: A vane pump including a rotating group comprising a thrust plate and a pressure plate which cooperate with a cam ring, rotor and vanes to provide a plurality of pump chambers. The thrust plate includes a pair of thrust plate passageways. Each thrust plate passageway comprises a pair of kidney shaped passages. The first kidney shaped passage is radially aligned with the discharge port of the thrust plate. The second kidney shaped passage is radially aligned with the inlet port of the thrust plate. The first and second kidney shaped passages are connected with a metering groove. Each thrust plate passage is isolated or blocked from the next adjacent thrust plate passage in the low-to-high pressure transition area of the thrust plate.

Abstract: A pump is proposed, in particular a vane pump, for a liquid or gaseous medium, which can be driven with the help of a motor, in particular an electric motor, and which comprises a rotor (15) that can be coupled to a drive shaft (29) of the motor and is arranged in an operating chamber and at least one pressure plate (25) that closes the operating chamber (11) in the axial direction and on its lateral face (27) facing away from the rotor (15) is connected to a pressure chamber (23), and also a coupling element (47; 47′) which surrounds part of the drive shaft (29), cooperates with at least one seal and contributes to sealing off the pressure chamber (23) with respect to the motor, the drive shaft (29) extending through a through opening (35) in the pressure plate (25). The pump (1) is characterized in that the coupling element (47; 47′) has a sleeve-like section (49) which engages in the through opening (35) in the pressure plate (25).

Abstract: A vane pump comprising a pump housing, including an inlet, an outlet, and therein a hollow space, a cam ring received in the hollow space, a rotor placed in the cam ring and defining a rotation axis. The rotor comprises plural vanes arranged in corresponding slots formed in the rotor with a slidable contact in a radial direction of the rotor. A first wall member is received in the hollow space, one side of the first wall member faces one side of the cam ring, and the first wall member comprises an intake passage provided with a groove that is formed so that a partition wall portion is defined between the intake passage and an interface between the first wall member and the cam ring. A pair of intake ports are formed on the one side of the first wall member, each intake port is connected with the inlet by the intake passage, and a pair of outlet ports are formed on the one side of the first wall member.

Abstract: An enclosed chamber external combustion rotary engine that converts thermal energy into mechanical energy, comprising of a tapered rotary disc with at least one perimeter quadrilateral vane oscillating inside enclosed expansion chambers formed on alternating sides of the rotary disc. The quadrilateral vane remains centered on the rotary disc, except for the transitional area, allowing fluid to provide force to the top and bottom sections of the quadrilateral vane for the length of the non-transition area. Fluid enters expansion chambers through one or more intake passages. Intake passages are formed with shut-off valves, which control the flow of fluid entering expansion chambers. Fluid pressure propels the vane through the expansion chambers causing the disc to rotate about an axis. Incorporated in the rotary disc is an output shaft from which work can be derived.

Abstract: A compact high efficiency vane pump is disclosed having a unique T-shaped vane and rotor slot configuration with a roller tip vane in a uniquely configured chamber. To minimize friction in chamber diameter, a pressure plate is provided which is hydraulically balanced, both in the forward and reverse pump and motor modes, having micro pressure pulses which vary multiple times per rotor rotation in order to compensate for varying hydraulic axial load on the housing.

Abstract: A bearing arrangement for a gear pump comprises first and second separate bearing blocks each having a respective block housing. The first and second bearing blocks together defining an axially directed bearing surface including a bridge region formed from an erosion resistant material which acts to separate inlet and outlet ports of the pump and a second region formed from a reduced friction material. The bridge region is defined by first and second insert members cast within respective ones of the block housings. The first and second bearing blocks are arranged such that respective surfaces of the first and second insert members mate with one another, and the first and second insert members are arranged such that the bridge region of the bearing surface is flush with the second region.

Abstract: A well production apparatus includes a down-hole gear pump and a transport assembly to which the gear pump is attached. The transport assembly is formed from a string of modular pipe assemblies having one or more passages for carrying production fluid from the bottom of the well to the surface. The passages can be arranged in a side-by-side configuration, and include pressure and return lines for driving the gear pump. The gear pump includes a hydraulically driven motor that is ganged with a positive displacement gear set. Both the motor and the pumping section have ceramic wear surfaces, the ceramic being chosen to have coefficients of thermal expansion corresponding to the coefficients of thermal expansion of the gear sets. The pumps and rotors have ceramic bushings rather than ball or journal bearings, and are operable under abrasive conditions.

Abstract: A multi-vane hydraulic motor for accessory drive in which the vanes of a hydraulically balanced rotor are primarily urged into operative engagement with a surrounding cam by forces of the hydraulic fluid in undervane passage produced by an associated hydraulic pump to eliminate requirement for biasing springs and spring attachment of prior art motor. A high pressure chamber provided between the motor housing and a pressure plate mounted therein is hydraulically connected to the vane chambers of the rotor of the motor for the hydraulic drive thereof. An end cap closing the motor housing has the hydraulic input and output lines operatively connected thereto.

Abstract: A vane pump includes a cylindrical rotor rotatable inside of an oval-shaped rotor chamber defined by a cam ring around the rotor. A thrust plate and a pressure plate on opposite sides of the cam ring cover the rotor chamber and are squeezed together by a pressure force attributable to fluid in a discharge chamber of the vane pump at a discharge pressure thereof. A first thrust face of the thrust plate is pressed against an end wall of a cavity of a pump housing in which the components are installed. Fluid at the discharge pressure is ported to one or more balance chambers between the thrust plate and the end wall of the housing. The balance chambers are defined by a gasket received in a groove of the first thrust face.