Abstract: A groove is applied to one or more contact surfaces of a journal bearing of a pump to increase a force applied to the contact surface(s). Each groove has an end exposed to discharge pressure of the pump so that the groove communicates the discharge pressure across the contact surface. The groove reduces an area of the contact surface over which fluid leakage results in a pressure differential, thereby increasing a net force applied to the contact surface. Applying the groove to the axial end face of the journal bearing enhances an axial force applied to the journal bearing whereas applying the groove to a radially facing land reduces friction between the journal bearing and the outer housing.

Abstract: In an external gear pump, a first bushing of a rotational shaft of a first gear has a second surface facing to a first surface of a pump body. A recess for supplying high-pressure lubricating oil between an inner circumferential surface of the first bushing and an outer circumferential surface of the rotational shaft is opened on the inner circumferential surface within a low pressure range associating with an inlet chamber of fluid. A bushing-side supply passage for supplying the high-pressure lubricating oil to the recess is formed within the first bushing. A bushing-side inlet port of the bushing-side supply passage is opened on the second surface within a high pressure range associating with an outlet chamber of the fluid. A body-side supply passage for supplying the high-pressure lubricating oil to a body-side supply port opened on the first surface is formed within the pump body.

Abstract: A geared volumetric machine including: a first and a second door; the second door operating at a greater pressure than the first door; one from between the first and second door being an inlet door of a fluid into the volumetric machine and the other door being an outlet door; a first cogged wheel in turn including a first and a second lateral flank; a second cogged wheel enmeshing with the first cogged wheel; a first and a second abutment between which the first cogged wheel is interposed and that respectively face the first and the second lateral flank of the first cogged wheel; a first grooved pathway which at least in a first angular position of the first cogged wheel connects a first and a second zone, the first zone including at least one of the compartments which is in communication with the second door.

Abstract: A compressor for gaseous fluids comprises a positive displacement gear pump, as typically used for liquid transfer, modified to effect compression of gases. The pump inlet includes a main inlet plus multiple secondary inlets feeding inlet gases to gear voids spaced from and moving away from the main inlet. The pump outlet includes a main outlet plus multiple feedback passages feeding partially pressurized outlet gases to gear voids spaced from and moving toward the main outlet. The supplemental inlets and feedback passages increase both the throughput of the compressor and the amount of compression imparted to the gases.

Abstract: A roots type fluid machine includes a case having a side wall, a pair of rotary shafts provided in the case, a pair of rotors engaged with each other and fixed to the pair of rotary shafts so as to extend axially, respectively, a suction space formed by the case and the pair of rotors for introducing fluid, a discharge space formed by the case for discharging fluid and the pair of rotors and a transfer chamber formed by the case and the rotor. The rotor has a rotor end surface. A clearance is formed between the side wall and the rotor end surface. The transfer chamber transfers gas introduced in the suction space to the discharge space in accordance with the rotation of the pair of rotors. The case has a guide groove formed in the side wall facing the rotor end surface. Gas leaked from the discharge space into the clearance is introduced to the transfer chamber through the guide groove.

Abstract: In an inner wall surface of a casing, grooves are formed that correspond to end faces of an outer rotor and an inner rotor, and seal members are disposed within the grooves, the seal members presses against the end faces of the outer rotor and the inner rotor. Inclined portions are provided in sealing portions of resin members of seal members, the sealing portions covering a closed portion. With this configuration, an internal pressure in the closed portion causes the inclined portions to separate from an outer rotor and an inner rotor when a brake fluid pressure within the closed portion increases to the point that the brake fluid is excessively compressed, releasing the brake fluid that is inside the closed portion. It is therefore possible to prevent the brake fluid pressure from increasing excessively within the closed portion.

Abstract: A gear pump capable of alternately distributing a fluid in two distinct utilization circuits without the need for a switch. The gear pump (1) comprises two fluid outlet ports (5, 6) connected to two fluid utilization circuits and linked to the discharge chamber (C) of the pump via an integrated commutation (7). These commutation (7) comprise two distribution circuits (50, 60), located in a fixed support plate (70), and two buffer channels (30, 40), located in the rotary toothed wheels (3), arranged so as to alternately open and close the distribution circuits according to a commutation cycle that approximately corresponds to the rotation of the toothed wheels over half a revolution.

Abstract: A lubricant-tight vane rotary vacuum pump, includes a pump stage (17) having a pump stage housing (10) with a gas inlet, compression chamber (11), and a gas outlet (51), a channel (50) connecting the compression chamber (11) with the gas outlet (51), and a groove (54) at least partially surrounding a mouth of the connecting channel (50) that opens into the gas outlet (51), so that lubricant, which is tossed out of the compression chamber, is collected in the groove (54) and re-entry of the lubricant back into the compression chamber (11) is prevented.

Abstract: The present disclosure relates to a vehicle transmission with fluid pump having a recirculation circuit. The recirculation circuit is configured to direct fluid from an outlet of the pump to an inlet during pump cycling. A method of manufacturing a fluid pump for use in a vehicle transmission is also disclosed.

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: The vane pump has a housing containing a rotor driven by a drive shaft. A number of grooves are distributed over the rotor circumference and extend in a substantially radial direction of the rotor, in each of which grooves a wing-shaped delivery element is guided in sliding fashion. The rotor is surrounded by a circumferential wall that extends eccentrically in relation to its rotation axis against which the radially outer ends of the delivery elements rest. Housing end walls of the pump housing adjoin the rotor in the direction of its rotation axis. An annular groove encompassing the rotation axis of the rotor is provided in at least one of the housing end walls and is situated opposite the radially inner regions of the grooves of the rotor and communicates with the pressure region via a connecting groove in the housing end wall. The connecting groove extends from the pressure region radially inward in the rotation direction of the rotor to the annular groove.

Abstract: The invention relates to a vane pump comprising a rotor which is arranged therein, rotatably driven by a drive shaft. The rotor is provided with several grooves which are distributed through the circumference thereof and which extend substantially radially with respect to the axis of rotation of the rotor. In each groove a blade-shaped conveying element is slidingly guided. The end walls of the pump housing are adjacent to the rotor in the direction of the axis of rotation thereof. At least one ring-shaped groove surrounding the axis of rotation of the rotor is embodied in at least one front side of the rotor. The ring-shaped groove is connected to lower areas restricted by the blades in the grooves of the rotor, and to pressure areas. In a preferred embodiment, the ring-shaped groove is formed in the rotor by shaping.

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 pneumatic motor includes a shell, two covers, a cylinder and a rotor. The shell defines a space, at least one inlet in communication with the space and at least one outlet in communication with the space. Each of the covers defines at least one radial channel and at least one arched channel in communication with the radial channel. The covers are disposed in the central space of the shell while the radial channel is in communication with the inlet. The cylinder defines a central space and at least one inlet in communication with the central space. The cylinder is located between the covers so that the central space thereof is in communication with the arched channels of the covers and that the inlet thereof is communication with the inlet of the shell. The rotor includes a plurality of fins movably mounted thereon.

Abstract: A positive-displacement pump, in particular for use in machines or dispensing fluids, including two elements that are with respect to one another and which mesh with one another (20, 30), each of them being rotatably mounted in the pump with centered coupling without interference with a corresponding centering body (18, 11a). At least one of the two above-mentioned ratable elements has a plurality of undercut regions (26, 34, 35)) at the location of the centering walls. The undercut regions (26, 34, 35) comprise a wall portion which is spaced with respect to the facing wall of the respective centering body.

Abstract: A positive-displacement pump, in particular for use in machines or dispensing fluids, including two elements that are with respect to one another and which mesh with one another (20, 30), each of them being rotatably mounted in the pump with centered coupling without interference with a corresponding centering body (18, 11a). At least one of the two above-mentioned ratable elements has a plurality of undercut regions (26, 34, 35) at the location of the centering walls. The undercut regions (26, 34, 35) comprise a wall portion which is spaced with respect to the facing wall of the respective centering body.

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 gerotor pump for pressurizing gasoline fuel is capable of developing pressures up to 2.0 MPa with good mechanical and volumetric efficiency and satisfying the durability requirements for an automotive fuel pump. The pump has been designed with optimized clearances and by including features that promote the formation of lubricating films of pressurized fuel. Features of the improved pump include the use of a shadow port in the side plate opposite the outlet port to promote balancing of high fuel pressures on the opposite sides of the rotors. Inner and outer rotors have predetermined side clearances with the clearances of the outer rotor being greater than those of the inner rotor in order to promote fuel pressure balance on the sides of the outer rotor. Support of the inner rotor and a drive shaft on a single bushing with bearing sleeves maintains concentricity. Additional features are disclosed.

Abstract: Two-inner gears are overlapped with each other through a partition wall and are eccentrically arranged at an inner peripheral side of an outer gear, and eccentric directions of both the inner gears are shifted from each other by 180° to the opposite side. By this, loads in an outer diameter direction due to a rise in fuel pressure affect one outer gear from the two inner gears oppositely to each other by 180°, so that an eccentric load is not generated, and sliding resistance of the outer gear to a cylindrical casing becomes small. Further, the number of teeth of the outer gear is made odd, and the number of teeth of the inner gears is made even.

Abstract: A vacuum pump has a housing accommodating a rotary shaft and a gas transferring assembly driven by the rotary shaft. The housing has an exhaust passage for exhausting gas outside the housing. The gas transferring assembly creates a vacuum. A lip seal for shaft seal is disposed between a pump chamber communicating with the exhaust passage and a region in which oil exists so as to slide relative to a circumferential surface of the rotary shaft. The lip seal has a back pressure surface in a back pressure region facing the pump chamber and a pressure surface facing the region in which the oil exists. A communicating passage in the housing intercommunicates the back pressure region and the exhaust passage for applying at least substantially the pressure in the exhaust passage to the back pressure surface.

Abstract: An oil pump apparatus includes an oil pump housing having a first suction port, a second suction port and a discharge port in the circumferential direction thereof. A shape of the end portion in the anti-rotational direction at the second suction port is formed to be along a shape of the end portion on the rotational direction side of one pump chamber which is sealed momentarily between the two suction ports, and a shape of the inner circumferential end portion of the first suction port is formed to be along the rotational trace of the end portion on the anti-rotational direction side of the pump chamber. A plural first pockets are formed on the driven rotor, and a second pocket is formed on the pump housing to communicate between the pump chamber and one of the first pockets when the pump chamber is communicated to the first suction port.

Abstract: A positive displacement rotary pump including a housing having an internal chamber and inlet and discharge ports, a sealing land on the housing between a downstream end of the inlet port and an upstream end of the discharge port, and a rotating group in the internal chamber defining a plurality of pump chambers. The pump chambers traverse in succession and at regular intervals the inlet port and the sealing land and the discharge port. The housing has a stationary pre-charging passage which communicates with the discharge port and overlaps the sealing land. The rotating group includes a plurality of rotating pre-charging passages which communicate with respective ones of the pump chambers.

Abstract: A screw-type compressor comprises a housing (12) in which a primary rotor (14) and a secondary rotor (16) are arranged each of which is provided with a shaft (18,24) and a screw rotor (20,26). The secondary rotor (16) is axially supported by the primary rotor (14). Only the primary rotor (14) comprises an axial bearing part (22) which is supported in an axial bearing part (66) of the housing (12). The omission of an axial bearing between the secondary rotor and the housing simplifies the support of the secondary rotor.

Abstract: A screw machine (10) has a rotor housing (12) defining overlapping bores (13, 15). Female rotor (14) is located in bore (13) and male rotor (16) is located in bore (15). The end faces (24, 26) of the female and male rotors, respectively, have depressions (44, 46, 54, 56, 64) formed in their surface whereby the interface area with the facing surface (51) of the outlet casing (53) is reduced.

Abstract: The present invention relates to a hermetic rotary compressor. More particularly, since the conventional rotary compressor has problems that the effect of a surge recess for reducing noises due to pressure pulsation is insufficient, and it is impossible to obtain the maximum compression efficiency, the present invention is constructed such that noises due to pressure pulsation can be reduced to the maximum and at the same time the compressive driving force required for compressing gaseous refrigerant is decreased to thereby improve the compression efficiency.

Abstract: A lubrication path in a gerotor motor extending in the face of the rotor or an adjoining surface from a gerotor cell having relatively high pressure to the central cavity of the device to provide cooling and lubrication fluid thereto.

Abstract: A gear pump comprising two gearwheels moving in opposite senses, the gears whereof engage with one another and thus, separated from one another in a pressure-tight manner, form a delivery side and a suction side; a central plate wherein the gearwheels are accommodated; a front and rear covering plate, which seal the gear pump from the environment, and conventional means of connecting the plates with one another, of supporting the gearwheels, of driving at least one of the gearwheels and of supplying and removing the liquid being pumped, during the delivery of silver halide emulsions exhibits no silver deposits--which bring the pump to a halt--on its faces, if on each face of each gearwheel there is provided at least one indentation having a sharp rear edge viewed in the direction of rotation.

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 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 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: A rotary blade air conditioner compressor is provided which includes a compressor housing having a cylindrical chamber. Chamber covers are mounted to respective ends of the cylindrical chamber. A reservoir is fluidly connected to an outlet and an inlet of the cylindrical chamber. A drive shaft is eccentrically mounted within the cylindrical chamber, with a rotor mounted on the drive shaft which is axially movable along the drive shaft. A plurality of radial slots are formed in the rotor which receive blade members that move radially in the slots to continuously contact the inner wall of the cylindrical chamber for expelling a mixture of gas and oil from the chamber. The gas and oil mixture comes from the reservoir and is supplied through a conduit to each end of the cylindrical chamber to axially displace the rotor with respect to the chamber covers.

Abstract: A rotary lobe pump has a pair of rotary lobes rotatably mounted in a pump chamber having end walls perpendicular to axes of the lobes and a side wall with which the rotors making sealing contact. At least one of the end walls is provided with a shallow groove in a region between the axes, the groove being of a selected depth and width to permit solid material lodged between the rotors and at least one of the end walls to become disengaged and flushed out while allowing a minimum of fluid to flow through the groove causing pressure loss in the pump.

Abstract: A thrust bearing of a scroll compressor to be used as a fluid compressor for a refrigeration or air conditioning unit, is designed to resist the moment exerted on the orbiting scroll member, and tending to tilt the orbiting scroll member, so as to prevent the clearance between a thrust surface and a surface of the orbiting scroll member slidingly supported thereon from being reduced or the surfaces from making local contact. The thrust bearing uses wedge shaped grooves having tip end portions in which fluid is compressed by the orbiting motion of the scroll member to generate dynamic pressure at one side of the compressor. This dynamic pressure maintains the clearance between the thrust surface and the surface of the orbiting scroll member thereby stabilizing the movement of the orbiting scroll member.

Abstract: A low pressure container type rolling piston compressor which includes a compression element, a motor element, a rotary shaft with an eccentric portion driven by the motor element, a cylinder for receiving therein the eccentric portion of the rotary shaft, a rolling piston having an inner circumference to which the eccentric portion is fitted and an outer circumference which rolls along the inner wall surface of the cylinder, a vane having an end which is in contact with the outer circumference of the rolling piston to divide the inner space of the cylinder into a high pressure chamber and a low pressure chamber, a pair of bearing plates for closing both open ends of the cylinder, a sealing container housing the above-mentioned structural elements and storing at its lower part a lubricating oil wherein a pressure in the sealing container is the same as that in the low pressure chamber and wherein an oil supplying passage is formed in either one of the pair of bearing plates for closing both open ends of the c

Abstract: A gear pump is disclosed which is adapted to convey a polymeric melt without significant leakage, and which comprises a pair of intermeshing gears. One of the gears is driven by a drive shaft which extends through a journal bore in the pump housing, and a by-pass duct extends between the journal bore and an area in the internal chamber of the pump which is adjacent but spaced from the intermeshing teeth and where the fluid cells defined by the intermeshing teeth are expanding. Also, at least one root of one of the gears includes a channel which leads to the area of the by-pass duct, and so that an intermittent suction resulting from the expanding fluid cells acts to withdraw any melt from the journal bore of the drive shaft and through the by-pass duct, to thereby prevent leakage of the melt outwardly through the journal bore.

Abstract: A first refrigerant gas passage is provided for conveying refrigerant gas under pressure to rearward ends of rotor vane slots through a rear bearing in order to supply back pressure to the rotor vane slots as well as to supply lubricant to the rear bearing. In addition to the first refrigerant gas passage, there is provided a second refrigerant gas passage for conveying refrigerant gas under pressure to forward ends of the rotor vane slots and a front bearing without conveying through the rear bearing and the rearward ends of the rotor vane slots in order to supply lubricant to the front bearing as well as to apply uniform back pressure on vanes, particularly at the forward and rearward ends thereof.

Abstract: A hydraulic internal gear machine includes a positive displacement unit for working liquid constituted by a rotary outer gear and an inner gear surrounding the outer gear and being in mesh therewith at one point to define a plurality of increasing liquid displacement chambers. The chambers are laterally bounded by a rotary disc which cooperates with a stationary control plate. The disc and the control plates are formed respectively with flow control openings for admitting pressure liquid into a half of the chambers and for discharging the liquid from the other half of the number of chambers. To compensate for the tilting moment acting on the rotary disc, the interface between the rotary disc and the control chamber is provided with arcuate recessed sections communicating with the openings in the rotary disc to apply pressurized liquid in the displacement chambers against both sides of the rotary disc.

Abstract: A rotary compressor comprises an open-ended cylinder having its open ends closed by end plates and an eccentrically rotatable rotor housed inside the cylinder. A hydrodynamic seal is provided on either the rotor or each of the end plates for minimizing any possible unwanted leakage of lubricant oil.

Abstract: A vane type hydraulic motor which is operable with seawater as the hydraulic fluid for undersea diver use. The motor is compact, lightweight and is lubricated by the seawater working fluid. The motor uses corrosion resistant materials with the requisite flexibility, mechanical strength, friction characteristics and low swelling rate when immersed in seawater. The motor structure provides durable seal means and pressure balanced operation which minimizes wear. The vane structure permits easy sliding vane movement, and uses the seawater pressure to control vane movement and sliding seal capability.

Abstract: A Wankel-type engine has a housing with a chamber therein having parallel, axially spaced side surfaces joined by an end surface which has a semi-circular contour in an axially longitudinal plane. A rotor, eccentrically mounted on a shaft carried by the housing for rotation in the chamber, has a pair of side portions adjacent to the chamber side surfaces and a plurality of lobes, each having an end portion which has a semi-circular configuration corresponding to the semi-circular contour of the chamber end surface. Multi-layer, self-expanding seals engaging the chamber end surface are carried by each rotor end portion, and the rotor side portions carry seals engaging the chamber side surfaces. Lubrication is supplied to the seals. The semi-circular chamber end surface is provided on a separate member mounted between a pair of housing members, or alternatively is provided on complimentary portions of a pair of housing members.

Abstract: An improved design for sealing and lubricating the moving parts of a rotary vane pump. An effectively operating lubricant distributing system is obtained in such a pump by forming radially extending passages through the pump drive shaft and attached rotor which connect the lubricant carrying hollow portion of the drive shaft with chambers located between the base of the vanes and the slits formed in the rotor in which the vanes radially slide. The rear bearing in which the drive shaft rotates is connected to these vane base chambers by means of an annular compartment having a lubricant duct connected thereto, thereby insuring the continuous flow of lubricant from the hollow portion of the drive shaft, through the vane base chambers and into the rear bearing. In an alternative embodiment of the present invention, the front bearing of the pump is connected with the hollow portion of the drive shaft via a lubricant passage formed on the suction side of the vanes.

Abstract: A rotor is journalled in a housing having gas inlet ports and outlet ports for compressed gas, the gas being compressed in working chambers formed between the rotor, an inner surface of the housing and vanes which periodically move inward and outward in slots in the rotor during its rotation and while sliding against said inner surface of the housing. Oil or other liquid is injected into the working chambers through grooves in at least one internal wall of the housing, the grooves being positioned to communicate with the working chambers through small recesses, located in edge portions of the rotor, during at least parts of the periods starting when a vane immediately trailing one of said recesses has just passed a said inlet port, thus blocking the connection between said last inlet port and the corresponding working chamber immediately preceding said vane, and ending when the pressure in said corresponding working chamber equals the liquid injection pressure.

Abstract: A gear pump is disclosed wherein the shafts of at least a pair of intermeshing gears are rotatably supported in bushings each with an axially extended lubrication groove formed in the bore of the bushing, one end of the lubrication groove being communicated through a low pressure chamber defined in the inner end face of the bushing with a portion of a suction port located adjacent to the root or dedendum circle of the gear while the other end of the lubrication groove being communicated with the suction port through a hole extended through the bushing or casing or notch formed therein, whereby part of the liquid drawn through the suction port upon rotation of the intermeshing gears is forced into the pressure chamber because of the fact that the liquid drawn into each tooth space of the gear is imparted with the impact speed directed in the radial direction of the tooth space due to the difference between the speed with which the liquid is drawn into the gear pump and the rotational speed of the intermeshing