Abstract: A hydraulic device has an inlet side and an outlet side and includes two meshing cogwheels. Each cogwheel has external oblique teeth and is arranged between an inlet side and an outlet side. At least one control groove is provided on an end side of the cogwheels. The control groove periodically produces a pressure equalizing connection during the rotation of the cogwheels.

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: 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 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 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 gear pump comprises a casing and gear rotors disposed therein. The gear rotors are lodged in bearing sections of plain bearings that are lubricated by the pumping medium. They have at least one cooling duct which is embodied such that cooling varies along the circumference and/or in the longitudinal direction and/or in the radial direction of the plain bearing.

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 rotary displacement machine has a housing and at least two annular displacement gears arranged in the housing and supported rotatably on a stationary axle, receptively. The at least two annular displacement gears have external teeth for conveying a fluid. At least two supply channels are provided in the housing and have a supply mouth, respectively, opening toward the annular displacement gears for supplying a fluid to the annular displacement gears. The supply mouth is configured such that, upon operation of the rotary, displacement machine, a fluid exiting from the supply mouth reaches either only the teeth of a single one of the annular displacement gears or only the teeth of the annular displacement gears rotating in the same direction.

Abstract: A hydraulic pump assembly includes a pump housing having a chamber defined therein, wherein the chamber includes a pair of cylindrically shaped portions each defining at least one end wall. The hydraulic pump assembly also includes a pair of rotary pump elements disposed for rotation within the cylindrically shaped portions of the chamber, and which cooperate to create a hydraulic pressure. The hydraulic pump assembly further includes a pair of cylindrically shaped shafts each having at least one end wall, and disposed within the pair of cylindrically shaped portions of the chamber and within the pair of pump elements. The shafts are fixed for rotation and are axially shiftable with respect to the pump elements. A hydraulic fluid within the chamber stabilizes at least one of the axially shiftable shafts such that the end face of the shaft is spaced from the end wall of the cylindrically shaped portion of the chamber when the hydraulic pump is in use.

Abstract: A gear pump comprises a casing (1) and gear rotors (2, 3) disposed therein. The gear rotors (2, 3) are lodged in bearing sections (15 to 18) of plain bearings (11 to 14) that are lubricated by the pumping medium. They have at least one cooling duct (39) which is embodied such that cooling varies along the circumference and/or in the longitudinal direction and/or in the radial direction of the plain bearing (11 to 14).

Abstract: The bearing cooling device causes cooling media to flow into the interior of a journal bearing 8 for supporting a shaft part 7 by lubrication of high viscous fluid and the interior of the shaft part 7 to cool the shaft part 7 and the bearing 8. At this time, cooling medium temperature of the bearing 8 is set to be higher than cooling medium temperature of the shaft part 7. It is constituted so that the cooling medium passes the cooling medium passage and thereafter passes the cooling medium passage internally of the bearing. A heated medium supply device for supplying a heated medium to each cooling medium passage may be provided. The bearing cooling device is used suitably for a gear pump.

Abstract: It is an object of the invention to provide a pump apparatus of simple construction with a bearing structure, for which a lubricant is unnecessary. A flow passage for a refrigerant (liquid ammonia) is formed in a housing to provide communication between a suction port and a discharge port, and slide bearing members formed of amorphous carbon are provided in the housing to be fitted into the flow passage to support a rotating shaft. Drive means for rotating the rotating shaft is constituted by a rotor, which is fitted into the flow passage and provided with the rotating shaft, and a stator, which is provided outside the housing to surround the rotor, and a pump body is provided midway the flow passage and connected to the rotating shaft to pump a fluid.

Abstract: A pump body for a medical gear pump for sucking and irrigating has a pot-like pump housing with two cylindrical openings, in which two meshing gearwheels are embedded. The driving gearwheel is, without pivot bearing, embedded in the opening. A lid is used for closing the pot-like pump housing. A trunnion protrudes from a bottom of the pump housing, onto which trunnion the driven gearwheel is mounted.

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: To provide a gear pump for carrying high viscous liquid, which keeps a bearing in a free state and enhances reliability relative to a leakage of cooling medium and a leakage of molten resins. The gear pump in which a pair of gear rotors 2 are supported on a body 1 of the gear pump through a bearing 6, a cover for preventing the bearing 6 from being slipped out is secured to the body 1, and a temperature adjusting medium passage 20 is formed in the bearing 6, wherein an inlet pipe 28 and an outlet pipe 29 to the temperature adjusting medium passage 20 are connected to the axial outer end of the bearing 6, an intermediate plate 10 is interposed between the axial outer end of the bearing 6 and the cover 11, the intermediate plate 10 being provided with an insert hole 31 for the inlet pipe 28 and the outlet pipe 29, the cover 11 being provided with a guide portion 32 having the inlet pipe 28 and the outlet pipe 29 loosely fitted therein to guide them to outside.

Abstract: A pump for moving a fluid has a housing with an internal chamber accommodating a pair of rotors mounted on parallel shafts connected with gears operable to rotate the shafts in opposite directions. Each rotor has opposite end walls and protrusions and pockets that register in non-contacting relation during rotation of the rotors. Thrust bearings cooperating with the gears, shaft, and housing maintain the end walls of the rotors in spaced relation relative to the adjacent walls of the housing.

Abstract: The bearing cooling device causes cooling media to flow into the interior of a journal bearing 8 for supporting a shaft part 7 by lubrication of high viscous fluid and the interior of the shaft part 7 to cool the shaft part 7 and the bearing 8. At this time, cooling medium temperature of the bearing 8 is set to be higher than cooling medium temperature of the shaft part 7. It is constituted so that the cooling medium passes the cooling medium passage and thereafter passes the cooling medium passage internally of the bearing. A heated medium supply device for supplying a heated medium to each cooling medium passage may be provided. The bearing cooling device is used suitably for a gear pump.

Abstract: Discloses apparatus for use with a modular fluid pump assembly, particularly pumps used to pump fluids containing entrained contaminants such as grit. The apparatus includes a pair of removable end plates attachable to a modular pump housing. A bearing assembly is detachably mountable on the exterior of the and plate and provides a cavity to receive a pump shaft fitted with a shaft seal and shaft bearing. A grit collar to surround the pump shaft is mountable on the interior side of the end plate. Replacement of the pump seals or bearings can be effected by removing the bearing assembly. More extensive maintenance, such, as replacement of the grit collar or pump gear or shaft, can be effected by removing the end plates.

Abstract: A screw pump provided with a first shaft and spaced therefrom and parallel thereto a second shaft mounted in a pump body. A first rotor is mounted on the first shaft and a second rotor mounted on the second shaft. Each of the first and second rotors having formed on an outer surface thereof one or more one helical vanes or threads intermeshing together so that rotary movement of the shafts will cause a fluid to be pumped. A first bearing arrangement is associated with the first shaft and a second bearing arrangement is associated with the second shaft. A bearing carrier is provided for each bearing arrangement and mounted within the pump body so as to be independent from each other.

Abstract: A journal bearing comprises a body having a central longitudinal axis, a cylindrical inner surface coaxially disposed around the longitudinal axis and defining an axial bore, and an outer surface including a peripheral planar section. A lateral face is disposed on an end of the body, and extends between the outer and inner surfaces of the body. A feed channel is formed in the lateral face at an acute angle with respect to the planar section and in an inward direction with respect to the axial bore. A first end of the feed channel communicates with the outer surface of the bearing at a location proximate to the planar section, and a second end of the feed channel communicates with the axial bore. A pocket is formed in the inner surface of the bearing in communication with the second end of the feed channel and extends along a substantially helical path from the lateral face of the bearing. At least a portion of the pocket has a width of greater magnitude than a corresponding depth of the portion.

Abstract: A gear pump having shafts mounted with rolling element bearings and having mechanical seals on the face of the gears provides improved “clean-in-place” ability. Preferably, washer-like seals are mounted on the face of the gears with a suitable adhesive and the cup-like seals are mounted in end housings. The end housings mate with a central housing enclosing the gears, to provide improved assembly.