Abstract: A gear pump and gear pump housing are provided. The gear pump housing includes an inner wall and an outer wall. The inner wall defines an inner pumping cavity having a pumping cavity inlet and a pumping cavity outlet. The outer wall surrounds at least part of the inner wall. The outer wall being spaced apart from the outer wall defining a pressure cavity between the inner and outer walls. The pumping cavity outlet is in fluid communication with the pressure cavity. As such, the pressure cavity may be supplied with high pressure fluid that is pumped. The gear pump includes a pair of pumping gears between the pumping cavity inlet and pumping cavity outlet.

Abstract: A rotary device is described for use in a rotary engine, or a compressor, or turbine, the rotary device comprising two rotors disposed adjacent each other and rotatable about substantially parallel axes of rotation. Each of the rotors has protrusions extending therefrom at regular intervals about the circumference of each to define an open portion of a sealable compression chamber between adjacent protrusions. Each protrusion has two side surfaces and a projecting end surface, wherein the meeting point between each side surface and the projecting end surface defines a tip. The two rotors are arranged such that upon contra rotation of the rotors, a protrusion of one of the rotors engages between a pair of protrusions on the other rotor, and the tips of the engaging rotor are in constant sealing contact with the opposing side surfaces of the pair of protrusions for a predetermined period of time.

Abstract: A rotary positive displacement pump comprising a pair of forwardly-positioned sealing arrangements and a pair of rearwardly-positioned selective sealing arrangements. The forwardly-positioned sealing arrangements each form a dynamic seal between a central portion of the one of the rotors and a corresponding hub proximate the forward ends of the shafts on which the rotors are received. The rearwardly-positioned selective sealing arrangements are located between the gear case and the pump body proximate the rearward ends of the shafts. When the rotors are secured to the shafts, the rearwardly-positioned selective sealing arrangements do not establish seals between the gear case and the pump body. However, when the rotors are removed from the shafts, the rearwardly-positioned selective sealing arrangements establish seals between the gear case and the pump body.

Abstract: There is provided a stator seal structure in a uniaxial eccentric screw pump by which the abrasion resistance of sealing mechanisms is improved and the pumped fluid can be prevented from stagnating in the sealing mechanisms. The stator seal structure is provided with a pair of sealing mechanisms for sealing between a housing and an intake side end portion, and between the housing and a discharge side end portion of the stator. The pair of sealing mechanisms is provided with ring-shaped secured rings respectively secured to the housing. The secured rings are respectively attached with elastic bodies for ensuring contact pressures between the sliding seal surface of the stator and the sliding seal surface of the secured rings with the elastic forces of the elastic bodies and for sealing between the secured rings and the housing.

Abstract: The invention relates to a gear wheel pump with two meshing gear wheels which are rotatably mounted within a pump housing by means of a driven driveshaft and a crankshaft journal and which form a pumping channel system between a pump inlet and a pump outlet. Several gaps are formed between the pump housing, the gear wheels, the driveshaft, and the crankshaft journal. One of the gaps between the driveshaft and one of the gear wheels contains means for the rotationally fixed connection of the driveshaft to the gear wheel. In order to prevent leakages penetrating to the connecting means, according to the invention the gap between the driveshaft and the gear wheel is sealed, with respect to the front faces of the gear wheel, by means of a sealant.

Abstract: A rotary piston pump with at least two double- or multi-lobe rotary pistons rotating in opposite directions, the drive shafts whereof include seals, wherein the seals are constituted as slip ring seals or lip seals or stuffing-box seals, which in each case are disposed on the shaft shoulder belonging to the respective rotary piston, and one slip ring per seal is provided with a locking device, which includes a large number of fixing positions. The seals are pushed onto a tubular shoulder of the rotary piston, the rotary piston is introduced into the pump housing, the securing element is connected to the slip ring seal in a form-fit manner by rotation of the rotary piston and the shaft shoulder is then rigidly connected to the drive shaft.

Abstract: A pump apparatus including a drive shaft and a driven shaft supported by bearing members, respectively, a center plate, first external gears, second external gears, first and second side plates, first and second seal members, a pressing means for applying a pressing force between the tooth tips of the respective external gears and the seal surface of the respective seal members in a closing region disposed between the respective external gears and the respective seal members, wherein contact between inner circumferential surfaces of the bearing members and an outer circumferential surface of the drive shaft is established on the side of the closing region, while the tooth tips of the respective external gears and the seal surface of the respective seal members in the closing region are kept pressed against each other by the pressing means.

Abstract: In a hollow seal member kept in abutted-engagement with a shaft hole formed in a housing via an elastic body and kept in sliding-contact with an outer circumference of a drive shaft for sealing against a leakage of fluid from a pump chamber, the seal member is provided with a seal part formed within an area at one end and kept in sliding-contact with the outer circumference of the drive shaft over a given hollow inner circumferential surface, and a rotation-stopping part formed within an area at the other end for restricting a movement of the seal member in a rotation direction of the drive shaft. A rotational resistance of the rotation-stopping part to the drive shaft is set to be less than a rotational resistance of the seal part.

Abstract: The invention relates to an apparatus for sealing a pump chamber of a rotary lobe pump vis-a-vis a fluid-free region of the rotary lobe pump, in particular in the region of a shaft duct, wherein the apparatus has two or more sealing elements, which can be disposed adjacent to a front side of a rotary piston disposed on a shaft in the pump chamber of the rotary lobe pump in such a way that a labyrinth gap extends between the sealing elements, said labyrinth gap being arranged in a radial direction relative to the shaft and in an axial direction in order to extend the seal land. According to the invention, the seal land is larger in a radial direction relative to the shaft than the seal land in an axial direction relative to the shaft.

Abstract: A shaft assembly includes a shaft with a first radial shoulder and a second radial shoulder along a shaft axis. A seal retaining sleeve is defined around the shaft axis to position a shaft seal. A retainer plate at least partially between the first radial shoulder and the second radial shoulder is adjacent to the seal retaining sleeve to position and provide access to the seal retaining sleeve and shaft seal.

Abstract: Rotary piston steam engine with equal double rotary pistons is provided with a balanced rotary variable inlet cut-off valve for enhanced efficiency. The exhaust steam from the primary expansion is routed to secondary expansion avoiding back pressure for additional efficiency. The rotary valve has balanced dual inputs and outputs on opposite sides. The exhaust steam from the primary expansion is taken off when the trailing face of the rotary piston passes the inlet port of the expansion chamber housing, the exhaust outlet secondary expansion being placed approximately 180 degrees from the primary expansion inlet in the curved portion of the expansion chamber housing wherein back pressure is not imparted to the primary expansion.

Abstract: A pump.

Abstract: A nonmetallic pump with a gear pump assembly having an adapter spool mounted to an electric motor. The pump assembly is designed to reduce manufacturing costs and to provide access for many service and maintenance tasks to be performed without breaking any of the pipe connections. The pump assembly also includes a splined shaft system and a lubricating fluid circulation system with spiral grooves located inside a pair of bearings disposed on opposite sides of the gear flights. The assembly also includes a replaceable precision liner that surrounds the gear flights to maintain a tight tolerance for optimal performance of the pump. Also, an O-ring disposed inside the front cover of the assembly provides for operation of the pump over a wide temperature variation with relatively loose manufacturing tolerances.

Abstract: A gear pump includes: a drive shaft; a first gear; a second gear; a first plate disposed between the first gear and the second gear, and arranged to liquid-tightly seal the first surfaces of the first and second gear; a pair of second plates disposed, respectively, on the second surfaces of the first and second gears, and arranged to liquid-tightly seal the second surfaces of the first and second gears, each of the second plates including a tooth top sealing portion having a seal surface arranged to seal a tooth top of the first gear and a tooth top of the second gear, and to form a suction portion with the first plate and the second plate; and an urging member arranged to urge the drive shaft toward the seal surface of the tooth top sealing portion of one of the first and second plates.

Abstract: A pump includes a pump body defining first and second cavities. First and second rotors are disposed in the first and second cavities between an inlet passage and an outlet passage and are in sealing relationship with each other during rotation of the rotors. A drive transmission mechanism is coupled to the first and second rotors for rotating the rotors in opposite directions. During a revolution of the first rotor, a vane projecting from the first rotor emerges from a recess of the second rotor, passes the inlet passage and the outlet passage, and enters a recess of the second rotor, while the inlet passage remains sealed from the outlet passage.

Abstract: Positive-displacement auxiliary pumping systems for use in pump apparatus of different configurations are disclosed. The positive-displacement auxiliary pumping systems are included in positive-displacement rotary pumps having a casing defining a pumping cavity, an inlet port connected to the pumping cavity, a discharge port connected to the pumping cavity, and a positive-displacement auxiliary pumping port connected to the pumping cavity. Pumping elements move within the pumping cavity of the casing and define a collapsing pocket that maintains fluid communication with the positive-displacement auxiliary pumping port after the collapsing pocket is no longer in fluid communication with the discharge port.

Abstract: A pressure equalization system reduces or eliminates a pressure differential across supercharger rotor shaft seals. Under high boost, rotor shaft seals often fail, allowing hot compressed air into an oil lubricated space containing rotor bearings and gears (and vented to ambient pressure), reducing oil lubricating effectiveness and resulting in increased wear and failure. Under low or non boost operation, the pressure differential is reversed causing the lubricating oil to leak into the supercharger interior and accelerated rotor seal wear. The pressure equalization system includes flow restrictive seals on both rotor shafts, separated from the rotor shaft seals by vented spaces, thereby isolating the rotor shaft seals from boost or vacuum in the supercharger interior and reducing or eliminating the pressure differential across the rotor shaft seals. Maintaining close to atmospheric pressure on both sides of the rotor shaft seals during boost and vacuum operation reduces wear and failures.

Abstract: A bi-rotational hydraulic motor having a selectively pluggable case drain with check valves incorporated into the thrust plate allowing excess lubrication fluid to pass from the bearings into the outlet port of the motor.

Abstract: The invention relates to a gear pump in which the amplitudes of the pressure impulses in a pressure chamber can be significantly reduced by a suitable embodiment of a first groove and/or a second groove. The circumferential walls of a pump chamber containing the pressure chamber, in an angular range extending toward the pressure chamber, each have a respective groove communicating with the pressure chamber, by which grooves a radial spacing between the outer circumference of two gear wheels disposed in the pump chamber and the circumferential walls is increased.

Abstract: An external gear pump including seals, bearings, bushing/seal housings, choke collars and shafts that are all removable for maintenance and/or replacement without removing either endplate or internals from the case assembly. The preferred pump includes four bearing caps that can be removed without removing the pump from its mounted position. By removing the four bearing caps, access is gained inside the pump housing to all of the seals, bearings, bushing/seal housings, choke collars and most importantly, the drive and idler shafts within the pump housing. Further, the two shafts can be slipped out of the pump without disturbing the internal parts and endplates. This capability facilitates maintenance and replacement of major components without removing the pump from its mounted position.

Abstract: A housing of a Roots pump is configured by joining a lower housing member and an upper housing member that are separable from each other. With the upper and lower housing members joined together, an upper accommodating portion and a lower accommodating portion form a front bearing accommodating portion and a rear bearing accommodating portion, which accommodate whole bearings, respectively. The Roots pump further includes bearing holders attached to the bearings and fixed to the lower housing member so that the bearings are received in the lower accommodating portion in a positioned state.

Abstract: A rotor assembly for a multi-stage pump is provided. The assembly includes a drive shaft, a rotor component and a drive component. The rotor component is located on the drive shaft and includes a rotor element for displacing fluid through the pump when the drive shaft is rotated. The drive component is anchored to the drive shaft and transmits torque from the drive shaft to the rotor component to effect rotation of the rotor component. A sleeve element is integrated with either the drive component or the rotor component and is used to space the rotor element from the drive component. An interface surface is located on the sleeve element for interacting with the other one of the drive component and the rotor component in order to maintain orthogonal alignment between the rotor element and the drive shaft. A driver is provided for transmitting torque between the drive component and the rotor component.

Abstract: The invention relates to a gear pump, especially for a power steering system, having a housing, a first cover and a second cover, the first cover being integrated into the housing.

Abstract: A seal apparatus includes at least one pair of gears; a side plate arranged adjacent to the pair of gears; and a housing sandwiching the side plate. At least one of the side plate and the housing includes a shoulder portion. The seal apparatus further includes a seal member arranged between the housing and the side plate and arranged at the shoulder portion. The seal member separates a low pressure area from a high pressure area in a radial direction of the gear. The shoulder portion is located in the low pressure area. At least a part of the seal member faces the high pressure area. The seal apparatus further includes a backup member reinforcing the seal member and facing a tip portion of the shoulder portion; and a containing portion formed between a root portion of the shoulder portion and the seal member to be capable of containing a part of the seal member at least when the seal member is elastically deformed.

Abstract: A telescoping gear pump comprises a bolt, a Bellville washer, a wear plate, a seal housing, a seal spring, a spur gear including a wear lobe, a seal ring and a case drain path, a shaft, a ring gear including a wear lobe, seal ring, and a case drain path, seal, a bolt assembly including a Bellville washer and bolt, and a pressure plate. The assembly provides pressure to a fluid to maintain a seal within a telescoping pump/motor during operation. The wear lobe reduces wear while maintaining fluid pressure.

Abstract: A Brayton cycle internal combustion engine of the open, or constant pressure type, in which rotary power is produced by the pressure of hot gasses against confined, rotor protrusions.

Abstract: An interlocking device for rigidly holding together the body and flange of a hydraulic machine includes a body, flange, gears, sealing elements acting as a body seal and lobe seal adapted to effectively seal pressurized oil pockets within the hydraulic machine with a back-up ring that prevents squeezing of the lobe seal and to retain it in its original position, appropriately dimensioned bush bearings adapted to act as load bearing journals. The interlocking device includes a plurality of bean-shaped dowels located at both inlet and outlet sides that hold the body and flange together with minimum relative displacement to ensure high volumetric efficiency of the hydraulic machine even at high operating pressures in excess of 275 bar or higher.

Abstract: Rotary piston steam engine with equal double rotary pistons is provided with a balanced rotary variable inlet cut-off valve for enhanced efficiency. The exhaust steam from the primary expansion is routed to secondary expansion avoiding back pressure for additional efficiency. The rotary valve has balanced dual inputs and outputs on opposite sides. The exhaust steam from the primary expansion is taken off when the trailing face of the rotary piston passes the inlet port of the expansion chamber housing, the exhaust outlet secondary expansion being placed approximately 180 degrees from the primary expansion inlet in the curved portion of the expansion chamber housing wherein back pressure is not imparted to the primary expansion.

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: 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: A power steering system hydraulic pump has a pump component which is to be sealed and a first pump cover. A flat sealing element is provided between the pump component which is to be sealed and the first pump cover.

Abstract: A screw compressor (10) provided with a compressor body (11), an oil supply tank (13), an oil supply line (60), and an oil recovery line (59), wherein the screw compressor is also provided with shaft seal sections (28, 41) located on opposite sides, in the direction of shafts (26, 38), of a compression chamber (24) of a screw rotor (25) and preventing both mixing of oil in bearings (27, 39, 40) into a compression chamber (24) and leakage of process gas from the compression chamber (24), a suction-opening return line (52) for interconnecting the shaft seal section (41) on the discharge side of the compression chamber (24) and a suction opening (17) of the compressor body (11), a supply-process-gas communicating line (61) for interconnecting the suction opening (17) of the compressor body (11) and the upper part of the oil supply tank (13), and a shaft seal section (53) for dividing between the inside of the compressor body (11) and an atmospheric environment.

Abstract: Rotary lobe pump and circumferential piston pump designs are disclosed where the drive and driven shafts are detachably connected to their respective rotors. The rotors are disposed in a pump or rotor casing, which is sandwiched between a head cover and a gearbox. The drive and driven shafts pass through mechanical seal assemblies, which are sandwiched between the first and second rotors and the gear box respectively. The seal assemblies can be serviced or replaced by simply removing the head cover and removing the rotors from the drive and driven shafts. The pump casing does not need to be removed to replace or service the seal assemblies. Further, the capacities of the disclosed rotary lobe and circumferential piston pumps can be modified without changing the gearboxes or shaft length. To modify a pump capacity, all that needs to be changed are the rotors, the pump or rotor casing and, in some designs, the head cover or cover plate.

Abstract: A gear pump includes: a drive shaft; a first gear; a second gear; a first plate disposed between the first gear and the second gear, and arranged to liquid-tightly seal the first surfaces of the first and second gear; a pair of second plates disposed, respectively, on the second surfaces of the first and second gears, and arranged to liquid-tightly seal the second surfaces of the first and second gears, each of the second plates including a tooth top sealing portion having a seal surface arranged to seal a tooth top of the first gear and a tooth top of the second gear, and to form a suction portion with the first plate and the second plate; and an urging member arranged to urge the drive shaft toward the seal surface of the tooth top sealing portion of one of the first and second plates.

Abstract: A multi-stage, clam shell, vacuum pump comprises two housing components (12) which are to be sealingly connected to one another such that an array of chambers extending longitudinally from an inlet region of the pump to an outlet region of the pump is defined thereby. Sealing means (30) are provided within the vacuum pump, between the two housing components, to prevent transfer of fluid in to and out of the vacuum pump where said components are connected. An array of discrete, elongate channels (33, 34, 36, 38) is provided, located between the sealing means (30) and the array of chambers (14, 16, 18, 20, 22). The channels serve to protect the sealing means (30) from fluid that passes through the chambers during operation of the vacuum pump. Each channel is configured to receive a barrier fluid having a different pressure than a barrier fluid to be received by an adjacent channel.

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: A fuel pump includes a housing having a cavity. The cavity has a rear surface, and a drive gear and driven gear are disposed in the cavity and in mesh with one another for pressurizing fluid. A floating wear plate and a fixed wear plate are disposed in the cavity and are in contact with the drive gear and the driven gear. A flow orifice is formed as part of the floating wear plate, and a portion of the pressurized fluid flows through the flow orifice to an area between the rear surface of the cavity and the floating wear plate, causing the floating wear plate to apply force to the drive gear and driven gear, and causing the drive gear and driven gear to apply force to the fixed wear plate, thereby compensating for any wear of the drive gear, driven gear, and wear plates.

Abstract: The invention relates to a gear pump having two meshing gear wheels configured of a driven gear wheel and a gear wheel moving along with the same. A rotatably supported drive shaft is provided for driving the gear wheel, the shaft being held in the pump housing by bearing means. A sealing means is associated with the drive shaft at the circumference between the gear wheel and the bearing means, the sealing means comprising a pressure ring resting against a face of the gear wheel. In order to prevent the gear wheel in the pump housing from starting to run, a second sealing means having a second pressure ring is disposed on the opposite face of the gear wheel at the circumference of the drive shaft between a second bearing means and the gear wheel, wherein both pressure rings have a sealing shoulder opposite the gear wheel, the shoulder being pressed against the face of the gear wheel under the action of a spring means.

Abstract: A rotary pump has a housing composed of two intersecting cylinder sections and pump rotors therein. The rotors roll off on one another and against the interior wall of the housing in a sealing manner and have two approximately club-shaped sections that are connected to each other at their narrower ends via a waisting. The club-shaped section of one rotor engages into the waisting of the other rotor. The rotors create in each phase of the rotation movement an evenly increasing intake volume in front of the inlet port and an evenly decreasing discharge volume in front of the outlet port, provision is made that, in order to improve the pumping performance and increase the stability under load, the surface lines, which function as sealing lines are designed sine shaped.

Abstract: An interlocking device for rigidly holding together the body (1) and flange (2) of a hydraulic machine comprises a body (1), flange (2), gears (12, 13), sealing means (7, 10) acting as a body seal and lobe seal adapted to effectively seal pressurized oil pockets within the hydraulic machine with a back-up ring (9) that prevents squeezing of said lobe seal and to retain it in its original position, appropriately dimensioned bush bearings (8) adapted to act as load bearing journals, wherein said interlocking device comprises a plurality of bean-shaped dowels located at both inlet and outlet sides that hold the body and flange together with minimum relative displacement to ensure high volumetric efficiency of said hydraulic machine even at high operating pressures in excess of 275 bar or higher.

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 housing (2) of a Roots pump (1) supports a drive shaft (3) and a driven shaft (4) with radial bearings (32, 33) so as to be rotatable. The housing (2) is formed by joining an upper housing member (20) to a lower housing member (10). The lower housing member (10) has lower bearing support portions (13), and the upper housing member (20) has upper bearing support portions (23). Opening edges (13a) of each lower bearing support portion (13) are positioned above the centers (P1) of the bearings (32, 33). An opening width (T1) of each lower bearing support portion (13) is smaller than the diameter (D1) of the bearings (32, 33). This structure suppresses the bearings (32, 33) from being separated from the lower housing member (10) during an assembling operation of the fluid machine.

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: Method includes applying additive material to a pre-selected region of a rotor for use in a Roots type blower assembly. The additive material restores structural dimension to provide measured rotor-to-rotor clearance and/or rotor-to-case clearance within the predetermined clearance range. The additive material may be an epoxy paint material or a plating material. The method includes measuring the clearances, preparing the rotor surface, applying the additive material, and re-measuring the clearance. The restored rotor may be returned to service, for example, in a locomotive diesel. The disclosure also provides a restored rotor including at least one region comprising the additive material. Additionally, the disclosure provides an apparatus including a dimensionally restored rotor.

Abstract: A drive transmission mechanism for transmitting torque between two or more rotary shafts in synchronization with one another without need for lubrication thereby eliminating occurrence of oil contamination, and an oil-free fluid machine equipped with the mechanism, are provided. A magnetic drive disk and a synchronization gear are attached to a rotary shaft connected to a drive motor, a magnetic drive disk and a synchronization gear is attached to a rotary shaft, torque transmission from the rotary shaft to the rotary shaft is carried out in two ways, via the magnetic drive disks and via the synchronization gears and at least one of the synchronization gears is made of plastic material. With the construction, torque transmit load between the rotary shafts via the synchronization gears is decreased, and a plastic gear or gears can be adopted for synchronization gears without reducing life of the gears without need for lubrication oil.

Abstract: A high-performance gear pump that does not require highly accurate machining is disclosed. The gear pump includes a housing having an accommodation chamber. A drive gear and a driven gear are positioned in contact with an inner surface of the accommodation chamber. The drive shaft is loosely received by the shaft hole of the drive gear, and the driven shaft is loosely received by the shaft support formed in the housing and the cover.

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: A gear pump, in particular for pumping material such as rubber mixes, includes an enclosure in which a central gear wheel and two peripheral gear wheels rotate. Teeth of the central gear wheel mesh with teeth of both peripheral gear wheels to pump material from an inlet to an outlet. The pump includes at least one feed chamber in which a feed mechanism delivers material to the inlet. The gear wheels are separately driven by a driving torque. A prestressing device applies a torsional prestress which presses the meshing teeth together for creating a seal between those meshing teeth to prevent leakage of material past the teeth.

Abstract: A gear pump includes a housing defining an accommodating chamber and a cover for sealing the accommodating chamber. The accommodating chamber accommodates a drive gear and a driven gear. Each of the drive gear and the driven gear includes an upper surface opposed to the cover and a lower surface opposed to the housing. An annular projection projects from the upper surface of the drive gear or the driven gear for contacting the seal plate. An annular projection projects from the lower surface of the drive gear or the driven gear for contacting the seal plate. The gear pump is capable of lowering the load when the drive gear and the driven gear are rotated.

Abstract: A Brayton cycle internal combustion engine of the open, or constant pressure type, in which rotary power is produced by the pressure of hot gasses against confined, rotor protrusions.