Abstract: A bearing for a gear pump including a bearing dam which has a surface, an inlet face relief located on the bearing dam, and a discharge face relief located on the bearing dam. A bearing dam wall is located between the inlet face relief and the discharge face relief and a bleed hole arrangement. The bleed hole arrangement includes a blind passage located on the discharge face relief, and a second passage positioned perpendicular to and connected to the blind passage. The second passage extends to the surface of the bearing dam. In an alternative embodiment, the second passage is of a stepped configuration. The bleed hole arrangement reduces cavitation on the bearing and gear surfaces by pulsing fuel into an inter-tooth volume formed between the gear teeth during gear rotation.

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

Abstract: A variable displacement vane pump having a vaned rotor adjustably contained within a cam member for rotation between fuel inlet and fuel discharge arcs. Adjacent vanes form enclosed fuel bucket areas which are expanded and axially-supplied with fuel in the fuel inlet arc and are contracted and axially-discharge the fuel in the fuel discharge arc. Fuel circulation is improved by providing a central recess at each vane tip and/or a central groove in the cam surface to prevent trapping, stagnation and overheating of fuel at the centerpoints of the bucket areas, which overheating can result in expansion of the vane tips, scoring of the cam surface and pump failure.

Abstract: To reduce squeeze pressure peaks on meshing rotors of a gear pump, recesses are molded into the product duct wall in the meshing area, on the delivery side and the suction side. The recesses are formed with spherical segments or other continuously curved surfaces.

Abstract: A fuel pump-suited for a Demand System motor vehicle fuel injection system includes a lower pressure vapor separating pump stage, a roller vane positive displacement high pressure pump stage, and a variable speed electric motor for driving an impeller in the vapor separating stage and a rotor in the roller vane stage. The roller vane stage has a bleed orifice therein located on an inlet side plate of the roller vane stage to intercept succeeding ones of a plurality of vane pockets on the rotor between a downstream end of a discharge port of the roller vane stage and an upstream end of an inlet port of the roller vane stage when the vane pockets are isolated from both ports.

Abstract: A rotary compressor, such as a sliding vane compressor, comprises a housing having a bore, a rotor assembly operatively arranged to rotate within the bore, vanes operatively arranged at the rotor assembly to move linearly relative to the rotor assembly and to form, together with the housing and rotor assembly, variable chambers, and a valve assembly arranged in the housing. The bore has a configuration divided into a expansion region of elliptical shape, a circular transition region, a polynomial-shaped compression region and a circular sealing region. The lubricant seal is composed of an oil injection port and oil grooves for trapping and transporting the oil. The valve assembly is provided in a recess portion of the housing and is configured as a thin blade covering each discharge port which has been relieved to minimize undesirably large difference of the pressure forces between the two sides of the blade. Oil grooves are provided in the rotor assembly and in end cap assemblies.

Abstract: A scroll type compressor which includes a fixed scroll and an orbiting scroll. Each scroll includes an end plate, a spiral element, at least one airtight compression chamber formed between the fixed and orbiting scrolls, a discharge port, and a drive mechanism for revolving the orbiting scroll relative to the fixed scroll, for compressing fluid in the compression chamber. The fixed spiral element and the orbiting spiral element include relatively thick tip portions having oppositely disposed flat faces. These faces are arranged in such a way as to periodically approach each other during the revolution of the orbiting scroll. A buffer portion is provided on at least one of the flat faces of the fixed and orbiting tip portions, for preventing over-compression of the fluid trapped between the flat faces.

Abstract: A pump 10 for materials having a viscosity up to about 3.0.times.10.sup.5 cps, such as cellulose acetate, has a pump body 12 formed with a gear receiving means and, mounted thereon for closing the gear receiving means 13, a pair of side plates 16, 18 having bearing receiving cavities 21. The side plates 16, 18 have pressure relief means 50 for relieving pressure that builds-up in the intermesh of gears 14 when highly viscous material, such as cellulose acetate, is being pumped. This means of diverting the pressure buildup enables the pump 10 and component parts, such as shafts 22, 24 and plain bearings 20, to resist premature failure due otherwise to the resultant load caused by residual pressure buildup. In the preferred embodiment, wear resistant ceramic plain bearings 20 are press fitted in the bearing cavities. Grooves or channels 30 in the interior walls 32 of bearings 20 provide a means to lubricate shafts 22, 24 rotatably supported in the bearings 20.

Abstract: A rotary positive displacement blower (10) of the Roots-type having inlet and outlet vents recess (60,62) for reducing fluid pressure build up in spaces between meshing, helical lobes (34a, 36a) on rotating rotors of the blower.

Abstract: A rotary positive displacement blower (10) of the Roots-type having inlet and outlet vents recess (60,62) for reducing fluid pressure build up in spaces between meshing, helical lobes (34a, 36a) on rotating rotors of the blower.

Abstract: A suction controlled gear ring pump effects a continuous decrease of the vacuum occurring in the feed cells of the pump at higher rotational speeds due to the long movement path of the feed cells from the end of the suction region to the beginning of the discharge opening and the thereby occurring diminution of the feed cells. In order to prevent squeeze oil when working at a lower rotating speed, the feed cells positioned successively in the feed direction are connected between the teeth respectively with the neighboring feed cells by overflow channels extending through the gear teeth, check valves in said overflow channels preventing a flow against the feed direction.

Abstract: A gear pump having improved low-temperature operation includes a housing with a cavity wherein is rotatably received a pair of meshed pinion gears. A pair of bushing members matched in external shape to a projection of the pair of gears and complementary to the housing cavity alone journal the pair of gears. The bushings and gears are freely movable relative to the housing at all operating temperatures for the pump, and the bushings are urged by fluid pressure forces into sealing cooperation with the gears and with the housing. The pump achieves an improved pumping volume by directing a trapped intermesh volume to the outlet port of the pump.

Abstract: A mechanical pump having a pumping chamber within which is positioned a pair of intermeshing rotors, preferably of the claw type, with each rotor mounted for rotation on respective shafts and the first rotor being associated with an inlet to the pumping chamber and the second rotor being associated with an outlet from the pumping chamber, wherein the second rotor has a cavity in its surface immediately adjacent the outlet.

Abstract: The trochoid pump includes an outer gear rotor and an inner gear rotor, which are different in number of teeth from each other, pressure chambers defined by adjoining teeth of both rotors and an end plate. The pressure chamber volumes are increased or decreased in accordance with rotations of both rotors. An intake opening communicates with the pressure chambers whose volumes are gradually increasing, out of the pressure chamber and an outlet opening communicates with the pressure chambers whose volumes are gradually decreasing. A starting end of the intake opening starts to be opened at a minimum gap position or a neighborhood position thereof. The starting end of the intake opening can be opened at a position advanced through a rotary angle of 4 degrees in the rotating direction of both rotors from the minimum gap position.

Abstract: Variable discharge and energy recovery is produced by an adjustable spool in fluid communication with the outlet chamber for adjustably providing pressurized fluid from the outlet chamber to selected portions of the demeshing area of the intermeshing teeth to vary the discharge flow of the pump and the amount of energy recovery. This results in maintaining a positive pressure in selected portions of the demeshing area as well as equalizing the pressure in the selected areas to the pressure in the outlet chamber.

Abstract: A vane-type motor is disclosed including a rotor disposed in a housing having a plurality of cam rings surrounding the rotor, which cam rings are displaceable relative to one another in the circumferential direction. Vanes associated with the cam rings subdivide a work chamber provided between the rotor and the cam rings into work cells and side plates laterally confine the work chamber. An inlet channel supplies pressure fluid to the work chamber and a discharge channel provides for discharge of the pressure fluid from the work chamber. Control channels are provided to preclude pressure impacts and noises with the cam ring displaced. The control channels terminate in the work chamber and connect the work chamber to the inlet channel. The rotor forms a control element for the control channels.

Abstract: A rotary vane pump has restricted fluid communication between the inlet and the trapped volume for about 4.degree. of rotation beyond when the vane starts past the inlet. Similarly there is restricted communication between the trapped volume and the outlet for about 4.degree. of rotation prior to the vane reaching the outlet. Additionally, in the preferred embodiment, the trapped volume is in restricted communication with the outlet prior to its isolation from the inlet.

Abstract: Hydraulic gear-driven rotary machine (pump or motor) in which the gears are free-floating with no supporting shaft or bearings. Their internal ducts rotate, providing a commutation with the stator ducts. This maintains the hydraulic equilibrium of the gears. A hydrostatic compensating device on the faces of the gears and on their toothing assures internal tightness. The hydraulic gear-driven rotary machine is suitable for operation at very high pressure with hydraulic equilibrium and internal tightness.

Abstract: A rotary compressor for helium gas has a cylinder defining a closed space therein, a rotor disposed in the closed space for eccentric rotary motion while making a sliding contact with the inner peripheral surface of the cylinder, and a blade slidably mounted on the cylinder and resiliently projected into the closed space for sliding contact with the rotor so as to divide the closed space into a suction chamber and a discharge chamber. The compressor further has an oil relief passage which is arranged to allow the discharge chamber to communicate with a space outside the discharge chamber in the final stage of the discharging stroke before the crank angle of the compressor reaches an angle corresponding to the position of a discharge port.

Abstract: This is a compressor apparatus having a central cavity, a fluid inlet and a fluid outlet coupled to the cavity, a pair of impellers having hollow interiors positioned in the cavity between the inlet and the outlet, each impeller having a plurality of exernal teeth engaging and intermeshing with the teeth on the other impeller and adapted for compressing a fluid, introduced into the cavity, means for rotating the impellers to draw the fluid out of the interior of the impellers and compress the fluid in the cavity and to force the compressed fluid out of the cavity through the outlet, each impeller having a fluid inlet on one end coupling the inlet of the cavity to the hollow interior of the impeller, each impeller further having a plurality of slots between each of the teeth on the impeller, said slots connecting the hollow interior of the impeller to the cavity through which fluid, introduced into the interior of the impeller, can exit the impeller and pass into the cavity, and a gate positioned in the hollow

Abstract: A screw displacement pump (10) for comingled material has a body (11) defining a chamber (12'). Inlets are provided for the admission of fluid to the chamber and an outlet is provided for discharge of fluid from the chamber (12') intermeshing screw members (40) are mounted for rotation within the chamber (12') for transporting comingled material from the inlet to the outlet, the threads (41,42) of the intermeshing screw members (40) being of opposite hand. The pitch of the screws (40) at the outlet end thereof is smaller than the pitch of the screws (40) at the inlet end thereof to cause compression of gaseous material being transported. Clearance is provided between the screws (40) and between the screws (40) and the walls of the chamber (12') to allow sufficient leakage of the material towards the inlet, when the material is in the liquid phase, to avoid a liquid lock.

Abstract: A scroll fluid apparatus including a fixed scroll member and an orbiting scroll member each having an end plate and a wrap, the two scroll members being maintained in meshing engagement with each other with the respective wraps facing inwardly to allow the orbiting scroll member to move in orbiting movement with respect to the fixed scroll member without rotating on its own axis. The fixed scroll member is formed with a discharge port at its central portion and a suction port at its outer peripheral surface to draw a gas by suction through the suction port and allow same to flow in a sealed space defined between the two scroll members and reducing its space during operation to thereby compress the gas and discharge the compressed gas through the discharge port.

Abstract: An improved supercharger or blower (10) of the Roots-type with reduced airborne noise and improved efficiency. The blower includes a housing (12) defining generally cylindrical chambers (32, 34) containing meshed lobed rotors (14, 16) having the lobes (14a, 14b, 14c, 16a, 16b, 16c) thereon formed with an end-to-end helical twist according to the relation 360.degree./2n, where n equals the number of lobes per rotor. The chambers include cylindrical wall surfaces 20a, 20b and end wall surfaces 20c, 24a which sealing cooperate with the rotor lobes and ends. Blower housing (12) also defines inlet and outlet ports (36, 38). The inlet port includes a longitudinal extent defined by housing wall surfaces (20f, 20f) and a transverse extent defined by housing wall surfaces 20g, 20i. Transverse wall surfaces (20g, 20i) are disposed substantially parallel to the associated rotor lobes.

Abstract: A rotary piston machine, in order to avoid losses due to compressed flows, has adjacent to a generating and/or sealing contact edge (21, 22) at least one recess (11a, 11e) and/or opening (12a, 12b) which extends beyond the contact curve (14a-14c) in at least approximately the direction of motion of the surfaces moving in relation to each other during the stroke or passage of the piston (6a") through the shut-off driver. The spatial dimensions of the recesses and/or opening are such that the flow in it is not substantially accelerated even when the direction is changed. An opening (11g, 11g') can be closed insofar as it is located in a nonmoving ring (6b). To prevent low pressures between surfaces moving away from each other (9c, 14c) a pressure compensation space (11e) is connected to the contact line (14c) of one of the surfaces.

Abstract: A screw compressor having a recess formed in the high-pressure end surface of the casing. This recess receives the fluid from a closed working space which has just been isolated from the discharge port and closed in the compression step. Consequently, the abnormal pressure rise in the closed working space, which is caused due to the compression of the fluid confined, is completely eliminated. The recess has a configuration involving a curve conforming with the leading flank of the female rotor at the instant at which the working space is isolated from the discharge port and closed.

Abstract: An improved supercharger or blower (10) of the Roots-type with reduced airborne noise and improved efficiency. The blower includes a housing (12) defining generally cylindrical chambers (32, 34) containing meshed lobed rotors (14, 16) having the lobes (14a, 14b, 14c, 16a, 16b, 16c) thereon formed with an end-to-end helical twist according to the relation 360.degree./2n, where n equals the number of lobes per rotor. The chambers include cylindrical wall surfaces 20a, 20b and end wall surfaces 20c, 24a which sealing cooperate with top lands (14d, 14e, 14f, 16d, 16c, 16f) of the rotor lobes and end surface (14g, 14h, 16g, 16h) of the rotor ends. Spaces (32a, 34a) between adjacent lobes of each rotor transfer volumes of low-pressure air from an inlet port (36) defined by the housing (12) to relatively high-pressure air at an outlet port (38) defined by the housing.

Abstract: A helical, positive displacement, external gear pump having a gear contact ratio greater than unity wherein the space between two meshing gear teeth registers with the cutoff edge of the outlet port at one end of the space and as it registers with the inlet edge of the inlet port at the opposite end of the space thereby eliminates the need for providing end plate recesses.

Abstract: A rotary fluid pressure device (11) is disclosed of the type including an internal gear set (17) wherein the toothed members (23,27) define expanding and contracting volume chambers (29). The device further includes relatively movable valve elements (19,55) having engaging valve surfaces (71,73). One of the valve elements defines fluid passages (67) communicating with the volume chambers and the other valve element defines a plurality of valve passages (63,65). There is provided a secondary valving including a fluid passage (7) defined by the first valve element and a fluid passage (77) defined by the second valve element, the secondary fluid passages being in fluid communication when the respective volume chamber is approaching its minimum volume position to prevent trapping of fluid, and as it is leaving its minimum volume position, to prevent cavitation.

Abstract: A worm type compressor comprises a cylindrical worm provided with a plurality of spiral-like passages in its inner periphery for forming fluid sealing chambers, a rotor slidably disposed within the worm and provided with an internal fluid outlet opening for discharging a compressed fluid and a pinion gear disposed within the rotor so as to be rotated about an axis perpendicular to and away from the rotor axis while engaged with the spiral-like passages.A worm type compressor further comprises a compressed fluid escape means which is provided in each of the finishing portions of the spiral-like passages of the worm for letting the compressed fluid escape from each of the spiral-like passages in the final stage of the fluid compressing step.

Abstract: A gear pump having a pair of intermeshing gears which operate in a housing and which are supported by a pair of bearing blocks which are biased towards the side faces of the gears for effecting a seal. There is interposed, between each bearing block and the adjacent side faces of the gears, a flexible plate which on its outer side is pressure-loaded by pump-delivery pressure admitted to an area of the plate confined by a linear seal element that includes part-circular portions extending around the gear axes at a radial distance appreciably smaller than the radius of the root circle of the gear teeth.

Abstract: In an external or internal gear pump or gear motor with one pair of helical spur gears, the trapping of fluid in the enclosed tooth cavity and the risk for cavitation in the said enclosed tooth cavity is considerably reduced by the shift of the pressure port connected and the suction port connected relief grooves at the leading lateral face of the helical gears in the direction of the suction port and the shift of the pressure port connected and suction port connected relief grooves at the lagging lateral face of the helical gears in the direction of the pressure port.

Abstract: A power steering pump having a cam with an internal cam surface defining pumping arcs, a rotor in said cam, pumping elements preferably in the form of slippers carried by the periphery of the rotor in sliding engagement with the pumping arcs, flow control valve means having a movable valve element responsive to both static pressure and velocity pressure of the displaced fluid on the high pressure side of the pump wherein provision is made for decreasing the volume of fluid delivered by the pump at high pressure upon an increase in the speed of the rotor, and means for equalizing the pressure between the volume of fluid between two adjacent pumping elements located at a high pressure outlet port and a corresponding volume of fluid between two other adjacent slippers located at a low pressure inlet port as the pumping elements pass through their respective pump cycles.

Abstract: In a pump having scroll vane impellers, rapid-opening additional discharge orts are formed by slats in the scroll vanes overlapping slats in the opposing end plates, thereby allowing fluids to be pumped without over-pressurization.

Abstract: A positive displacement device utilizing at least two rotors which roll sealingly on one another at a common pitch surface speed. Outwardly extending lobes on one rotor sealing engage the cylindrical bore of the housing of the device, fluid traversing the device circumferentially in the annulus between such bore and the pitch surface of the rotor. Speed of rotation of the two rotors is controlled by a timing chain running between sprockets mounted on the rotor shafts.When the lobe passes the line of sealing contact, a cavity is provided in the meshing rotor, and the lobe makes sealing contact with the wall of this cavity during at least that interval when there is no sealing contact between the pitch surfaces, i.e., the interval when the mouth of the cavity is passing through dead center.

Abstract: A pressure plate provides a trapped pressure relief groove oriented along the line of action of mating gears in a gear pump. The groove communicates the fluid trapped between the gear teeth with both the inlet and outlet, thereby reducing high squeezed pressures and lowering hydraulic noise levels. Noise suppression is apparent at all speeds, and is particularly apparent at high pump operating speeds.

Abstract: A gear pump or motor in which a pair of meshing gears are rotatably mounted in a housing and in which a throttle passage provides communication between a region of the housing in which, during rotation of the gears, high pressure is maintained and the region of the interstices between engaging teeth of the gears at which these interstices increase during such rotation, to prevent cavitation and to essentially reduce noise during operation.

Abstract: In the embodiment of the invention as depicted, the same comprising a rotary compressor, a channel or passageway is provided in the machine to communicate two variable volume chambers which are formed by rotary pistons and walls of the compressor housing, to equalize pressure in the two chambers. The purpose here is to prevent one chamber from pre-compressing before the other, so that a small pocket formed between the rotors by the inter-engaging teeth will not come up to pressure, and be expanded back into the inlet, to avoid a clearance loss and a waste of horsepower.

Abstract: A semi-positive displacement pump of modular structure that includes a center plate, a pump defining housing removably secured to a first side thereof, a gear containing housing removably affixed to a second side, first and second impellers disposed in spaced relationship in the pump cavity between a fluid inlet and fluid outlet defined therein. The pump may be selectively driven either manually or by power means. The bottom of the pump chamber and the surface of the center plate most adjacent the pump chamber have first and second sets of aligned pressure relief cavities formed therein. The first and second impellers include first and second cylindrical hubs of substantial diameter that have their ends closely disposed to transverse center portions of the bottom of the pump chamber and center plate defined between the first and second pressure relief cavities formed therein.

Abstract: A hydraulic gear-type machine has two meshing gears with axis-defining shafts received in respective journals having end faces turned axially toward the respective gears and formed with cutouts opening in opposite directions in line with input and output passages formed in a housing carrying the journals and enclosing the gears. The journals abut flatly at the cutouts along surfaces extending axially to immediately adjacent gears and chordally to cylindrical continuations of the outer surfaces of the journals. Each of the journals on each axial side of each gear is therefore formed with a recess opening toward the inlet passage and with a recess opening toward the outlet passage.

Abstract: This invention relates to an improvement in a rotary piston machine of trochoidal construction for compressing a gaseous medium having working chambers between a trochoidal piston and a housing corresponding to the coordinated outer envelope curve, said working chambers being separated from each other by radial seals in the housing, and outlet openings closed-off by means preventing backflow for discharging medium from the working chambers, the improvement comprising trough-shaped recess means in the peripheral piston surface which, in the dead center position of the piston, are positioned immediately ahead of a radial seal.