Abstract: A cooling lubrication system comprises a dry sump, an oil tank, and a pump system that operates an oil circuit in which an oil pump delivers oil from the dry sump into the oil tank, and the pump system comprises a vane cell pump and two gerotor pumps on a shaft.

Abstract: A multistage pump assembly with at least one co-used shaft comprises a first pump set including at least two vacuum chambers. Each vacuum chamber of the first pump set is installed with at least one rotor and a first driving shaft, the rotor is installed to the first driving shaft in the same vacuum chamber of the first pump set. The first driving shafts in the first pump set are co-shafted, that is, rotors in the at least two vacuum chambers of the first pump set are installed at the same first driving shaft. A second pump set includes at least one vacuum chamber which includes at least one rotor and a second driving shaft. An outlet of the second pump set is connected to an inlet of the first pump set through an air tube.

Abstract: According to one embodiment of the invention, a gerotor apparatus includes an outer gerotor having an outer gerotor chamber, an inner gerotor, at least a portion of which is disposed within the outer gerotor chamber, and a synchronizing apparatus operable to control the rotation of the inner gerotor relative to the outer gerotor. The inner gerotor includes one or more entrance passages operable to communicate a lubricant into the outer gerotor chamber.

Abstract: A pump device having a vane-type pump has a check valve in a fluid duct which leads from a pressure region to an under-vane region. The check valve blocks in the direction of the pressure region, preventing pressure from escaping from the under-vane region into the pressure region during the start-up of the vane-type pump.

Abstract: Housingless positive displacement pump assembly comprises one or more vane or gerotor type housingless positive displacement pump units, each comprising pump unit components. One or more retaining rods extend through axially aligned holes in a mounting flange at one end of the pump assembly and the pump unit components to hold the pump unit components in stacked relation to one another and connect the pump assembly to the mounting flange.

Abstract: A pump (1) having a housing (15) with a suction-side fluid inlet (4) and with a pressure-side fluid outlet (5), having a first pump unit (2, 11) and having a second pump unit (3, 12), the first pump unit being connected hydraulically in parallel with respect to the second pump unit, wherein the housing (15) is of modular construction and has a first housing part (3), which houses the first pump unit (11), and also a second housing part (14), which houses the second pump unit (12), wherein the fluid inlet (4) of the housing (15) forms in each case one fluid connection to the first and to the second pump unit (2, 3, 11, 12), and wherein the fluid outlet (5) of the housing (15) forms in each case one fluid connection to the first and to the second pump unit (2, 3, 11, 12).

Abstract: A pump (1, 10) having a housing (15) with a suction-side fluid inlet (4) and with a pressure-side fluid outlet (5), having a first pump unit (2, 11) and having a second pump unit (3, 12), the first pump unit (2,11) being connected hydraulically in parallel with respect to the second pump unit (3, 12), wherein the first pump unit (2,11) is a pump unit that exhibits a constant volume flow, wherein the second pump unit (3, 12) is a pump unit that exhibits variably adjustable volume flow.

Abstract: Rotary expansible chamber (REC) devices having one or more working-fluid ports that are adjustable, for example, in size or location. In some embodiments, the variable port mechanisms can be used to control any one or more of a plurality of operating parameters of a REC device independently of one or more others of the operating parameters. In some embodiments, the REC devices can have a plurality of fluid volumes that change in size during rotation of the REC device, and that transition to a zero volume condition during the rotation of the REC device. Systems are also provided that can include one or more REC devices. Methods for controlling various aspects of REC devices, including methods of controlling one or more operating parameters, are also provided.

Abstract: A variable output assembly including a hydraulic pump disposed on a pump running surface located on a center section, end cap or other hydraulic mounting member. The pump may be a gerotor or other rotatable pump body. A support member is disposed between the pump running surface and the pump and includes a pump support surface having openings to permit fluid communication between the support member and the pump running surface. The support member is movable between neutral and a plurality of positions corresponding to forward and reverse directions of the output. In forward and reverse positions, the support member permits fluid communication between the pump and a first porting system, and in the neutral position the support member permits fluid communication between the pump and a sump through the support surface openings and a second porting system.

Abstract: An expander-compressor unit (10) includes a two-stage rotary expansion mechanism (3) having a first cylinder (41) and a second cylinder (42). In the expansion mechanism (3), a suction port (71) facing a working chamber on the upstream side in the first cylinder (41) and a discharge port facing a working chamber on the downstream side in the second cylinder (42) are formed. An intermediate plate (43) is provided between the first cylinder (41) and the second cylinder (42). In the intermediate plate (43), a communication passage (43a) for allowing communication between a working chamber on the downstream side in the first cylinder (41) and a working chamber on the upstream side in the second cylinder (42) is formed. The communication passage (43a) does not communicate with the working chamber in the first cylinder (41) during the suction process, and communicates with the downstream working chamber in the first cylinder (41) at or after the end of the suction process.

Abstract: A high-pressure pump for supplying fuel to an internal-combustion engine has a pump body and an actuating shaft which extends along a longitudinal axis and which is supported rotatably about the longitudinal axis by the pump body. The shaft has an eccentric portion and a prismatic jacking end. A first pumping station has a gear engaged with the prismatic jacking end and a second pumping station has at least one piston. The piston is slidable relative to the pump body transversely with respect to the longitudinal axis and is actuated by the eccentric portion of the actuating shaft. The prismatic jacking end is made of a harder material than the material with which the remainder of the actuating shaft is made.

Abstract: The catheter device comprises a drive shaft connected to a motor, and a rotor mounted on the drive shaft at the distal end section. The rotor has a frame structure which is formed by a screw-like boundary frame and rotor struts extending radially inwards from the boundary frame. The rotor struts are fastened to the drive shaft by their ends opposite the boundary frame. Between the boundary frame and the drive shaft extends an elastic covering. The frame structure is made of an elastic material such that, after forced compression, the rotor unfolds automatically.

Abstract: A unified variable displacement pump having a housing which includes a fluid pump and a vacuum pump. A portion of the housing is part of the fluid pump, and a portion of the housing is part of the vacuum pump. A shaft extends through the fluid pump and the vacuum pump. A vacuum pump rotor is formed as part of the shaft, and a vane pump rotor is mounted to the shaft such that when the shaft rotates, the vacuum pump rotor and the vane pump rotor rotate, causing the fluid pump to pump fluid and the vacuum pump to generate a vacuum. The vacuum pump and fluid pump are combined into a single component driven by a single shaft.

Abstract: The expander-compressor unit 70 includes the closed casing 1, the expansion mechanism 4 disposed in the closed casing 1 so that a surrounding space thereof is filled with the oil, the compression mechanism 2 disposed in the closed casing 1 so as to be positioned higher than the oil level, the shaft 5 for coupling the compression mechanism and the expansion mechanism 4 to each other, and the oil flow suppressing member 50 disposed in the surrounding space of the expansion mechanism 4 so that the space 55a filled with the oil is formed between the expansion mechanism 4 and the oil flow suppressing member 50. Thereby the flow of the oil filling the inner reserving space 55a is suppressed, and thus, heat transfer from the high temperature oil to the low temperature expansion mechanism can be reduced.

Abstract: A rotary expander includes: a cylinder (61); a piston (62) disposed inside the cylinder (61); closing members disposed with the cylinder (61) being sandwiched therebetween; and an injection passage for introducing further a working fluid in the expansion process of the working fluid. An introduction outlet (65c) of the injection passage leading to the working chamber (69) is provided at a position located inwardly away from the inner circumferential surface (61b) of the cylinder (61), on one of the closing members, in such a manner that the injection passage and the discharge passage are not communicated with each other.

Abstract: A lubricating pump having a first stage and a second stage; the first stage in turn has an intake connectable hydraulically to a tank of lubricating fluid, and a delivery outlet connectable hydraulically to a lubricated member; the first stage compresses the lubricating fluid from the tank to a pressure for supply to the member; the second stage in turn has an inlet connectable hydraulically to a casing housing the member, and an outlet connectable hydraulically to the tank; the second stage feeds the lubricating fluid in the casing back into the tank; the second stage is a Roots type, and has a first and a second rotor rotating about respective axes to feed the lubricating fluid from the inlet to the outlet; and the first and second rotor are operated by the first stage.

Abstract: A variable output assembly including a hydraulic pump disposed on a pump running surface located on a center section, end cap or other hydraulic mounting member. The pump may be a gerotor or other rotatable pump body. A support member is disposed between the pump running surface and the pump and includes a pump support surface having openings to permit fluid communication between the support member and the pump running surface. A motor assembly may be hydraulically connected to the pump running surface by a first porting system, and a sump is hydraulically connected to the pump running surface by a second porting system. The support member is movable between neutral and a plurality of positions corresponding to forward and reverse directions of the output.

Abstract: A refrigeration cycle apparatus 1 includes a refrigerant circuit in which a refrigerant circulates. The refrigerant circuit is formed by connecting in sequence a compressor 2 for compressing the refrigerant, a radiator 3 for allowing the refrigerant compressed by compressor 2 to radiate heat, a fluid pressure motor 4 as a power recovery means, and an evaporator 5 for allowing the refrigerant discharged by the fluid pressure motor 4 to evaporate. The fluid pressure motor 4 performs a process for drawing the refrigerant and a process for discharging the refrigerant. These processes are performed substantially continuously.

Abstract: It is an object of the present invention to provide a multistage compressor employing a gas injection system for a CO2 cycle which is able to improve the compression efficiency and the compression performance thereof. In a multistage compressor (2) for a CO2 cycle (1) that carries out two-stage compression by discharging CO2 refrigerant gas compressed in a low-stage side rotary compressing mechanism (4) into a closed housing (3) and taking intermediate pressure refrigerant gas in the closed housing (3) by a high-stage side scroll compressing mechanism (5), a gas injection circuit (15) for injecting intermediate pressure CO2 refrigerant gas extracted from a refrigerant circuit into the closed housing (3) is connected to the closed housing (3), and the pressure ratios of the low-stage side rotary compressing mechanism (4) and the high-stage side scroll compressing mechanism (5) are substantially equivalent, and the ratios of displacement volume are substantially equivalent.

Abstract: The present invention relates to an evacuation apparatus for evacuating a vacuum chamber of a substrate processing apparatus for processing a substrate such as a semiconductor wafer or liquid crystal panel. An evacuation apparatus according to the present invention includes a first vacuum pump connected to a vacuum chamber, and a second vacuum pump connected to the first vacuum pump. The first vacuum pump has a pair of multistage pump rotors.

Abstract: A fluid machine (101) includes a first compressor (107) and a second compressor (108). The first compressor (107) has a first closed casing (111), a first compression mechanism (102a), an expansion mechanism (104), and a shaft (113). A first oil reservoir (112) is formed in the first closed casing (111). The second compressor (108) has a second closed casing (125) and a second compression mechanism (102b). A second oil reservoir (126) is formed at a bottom portion in the second closed casing (125). The first closed casing (111) and the second closed casing (125) are connected to each other by an oil passage (109) so that a lubricating oil can flow between the first oil reservoir (112) and the second oil reservoir (126). An opening (109a) of the oil passage (109) on a side of the first closed casing (111) is located above the expansion mechanism (104) with respect to the vertical direction.

Abstract: There is provided a high performance compressor that causes no possibility of mixing foreign materials or of leaking refrigerant, that reduces strain otherwise generated in a compressor mechanism section and that is highly reliable even for a long-term use. The compressor mechanism section in which pairs of prepared holes are formed at a plurality of points on an outer peripheral face thereof is disposed within the closed container. Caulking punches are positioned to positions corresponding to those of the prepared holes and a region including the corresponding positions is heated. Then, when the punches are driven by pressing machines, portions of the container wall of the closed container plastically deform as the convex portions and enter the prepared holes. When the container wall cools down, the pair of convex portions of the container clamps a part between the prepared holes.

Abstract: There is provided a compressor capable of feeding lubricating oil to a blade of a rotary type compression mechanism even if the oil level in an oil reservoir lowers. The compressor includes a low stage-side rotary type compression mechanism having a rotor, and a blade reciprocating with the rotation of the rotor while the tip end thereof is in contact with the rotor; a high stage-side scroll type compression mechanism for sucking and compressing refrigerant gas compressed by the low stage-side rotary type compression mechanism; a positive displacement lubrication pump for feeding lubricating oil to the high stage-side scroll type compression mechanism; and an oil feeding path for feeding the lubricating oil, which is fed to the high stage-side scroll type compression mechanism, toward the blade of the low stage-side rotary type compression mechanism.

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

Abstract: Two rotary mechanism parts (70, 80) are provided in a rotary expander (60). The first rotary mechanism part (70) is smaller in displacement volume than the second rotary mechanism part (80). A first low-pressure chamber (74) of the first rotary mechanism part (70) and a second high-pressure chamber (83) of the second rotary mechanism part (80) are fluidly connected together by a communicating passageway (64), thereby forming a single expansion chamber (66). High-pressure refrigerant introduced into the first rotary mechanism part (70) expands in the expansion chamber (66). An injection passageway (37) is fluidly connected to the communicating passageway (64). When an motor-operated valve (90) is placed in the open state, high-pressure refrigerant is introduced into the expansion chamber (66) also from the injection passageway (37). This makes it possible to inhibit the drop in power recovery efficiency, even in the condition that causes the actual expansion ratio to fall below the design expansion ratio.

Abstract: In a compression/expansion unit (30) serving as a fluid machine, both a compression mechanism (50) and an expansion mechanism (60) are housed in a single casing (31). An oil supply passageway (90) is formed in a shaft (40) by which the compression mechanism (50) and the expansion mechanism (60) are coupled together. Refrigeration oil accumulated in the bottom of the casing (31) is drawn up into the oil supply passageway (90) and is supplied to the compression mechanism (50) and to the expansion mechanism (60). Surplus refrigeration oil, which is supplied to neither of the compression and expansion mechanisms (50) and (60), is discharged out of the terminating end of the oil supply passageway (90) which opens at the upper end of the shaft (40). Thereafter, the surplus refrigeration oil flows into an oil return pipe (102) from a lead-out hole (101) and is returned back towards a second space (39).

Abstract: Oil supply grooves (74, 84) are formed respectively in a rotating shaft (70) of a compression mechanism (50) integral with an electric motor (40) and in a rotating shaft (80) of an expansion mechanism (60). The rotating shafts (70, 80) are coupled together by engagement between an engagement convex portion (85) and an engagement concave portion (75) which are formed respectively in shaft ends of the rotating shafts (70, 80). And, a seal groove (S) is formed in the peripheral surface of the engagement convex portion (85) and an O-ring (R) is engaged into the seal groove (S). Hereby, lubrication oil leakage from between the engagement convex portion (85) and the engagement concave portion (75) is prevented.

Abstract: A complex dry vacuum pump including a root rotor and a screw rotor is disclosed for manufacturing semiconductors and/or displays in a vacuum state in a process chamber, and discharging gaseous material and/or by-products generated during manufacturing to the exterior of the process chamber. The pump can provide high gas compression transfer efficiency so as to form a vacuum in the process chamber and/or keep high gas compression transfer efficiency when the gaseous material and/or by-products are discharged. Balance between the root rotor and the screw rotor can prevent vibration and noise generated in the vacuum pump, and molding material associated with the pump may allow a stator coil to be separated and prevent various by-products from flowing from the vacuum pump.

Abstract: The present invention relates to a rotary machine that can be employed in different applications such as, for example, a combustion engine or compressor. The invention further relates to an assembly of two or more rotary machines and a combustion engine based on the rotary machine. The machine is substantially composed of a helical screw-shaped rotor connected to an outgoing shaft journal, which screw-shaped rotor rotates in a cylindrical housing. The machine is further provided with rotating chamber dividing bodies whose rotation is synchronised with the rotating screw-shaped rotor. The chamber dividing bodies divide the helical screw grooves into chambers whose volume varies with rotation of the screw-shaped rotor.

Abstract: Disclosed is a displacement type expansion machine. In the displacement type expansion machine, a communicating passage (72) for allowing fluid communication between an expansion-process intermediate position and an outflow position in an expansion chamber (62) is provided thereby to allow the fluid at the outflow side to return to the expansion chamber (62). Such arrangement prevents the pressure of the expansion chamber (62) from being lowered to an excessive extent in predetermined operating conditions, thereby avoiding the drop in power recovery efficiency.

Abstract: A composite fluid machine has a first and a second fluid delivering mechanisms. The first fluid delivering mechanism includes an accommodation chamber, a movable body, and a suction space. The movable body is accommodated in the accommodation chamber.. The suction space is defined by the accommodation chamber and the movable body. The suction space is connected to the inlet, and the flow rate of the fluid introduced into the suction space is displaced. The movable body performs a suction movement and a discharge movement.. The second fluid delivering mechanism is combined with the first fluid delivering mechanism and is located upstream of the first fluid delivering mechanism to deliver the fluid to the suction space of the first fluid delivering mechanism.. Lobes of helical roots rotors are twisted in a respective direction around the rotational axis.

Abstract: The disclosed apparatus includes a stator and a rotor disposed for rotation within the stator. An inner wall of the stator defines one or more collider chambers. Rotation of the rotor causes movement of fluid disposed between the rotor and stator and establishes a rotational flow pattern within the collider chambers. The fluid movement induced by the rotor increases the temperature, density, and pressure of the fluid in the collider chamber.

Abstract: Conventionally, when a canned motor is used in the drive part of a rotary dry vacuum pump, there is found a problem that reaction produced gas flows into the interior of the canned motor to thereby break down the canned motor and thus the rotary dry vacuum pump.

Abstract: A scroll compressor includes: a frame fixedly installed in the casing to support a rotary shaft of the driving motor and having a second suction opening at its one side and a second discharge opening at its other side; a fixed scroll fixedly installed at the frame and having a first suction opening at its edgemost and a first discharge opening at its central portion; an orbiting scroll forming a first compression chamber by being engaged with the fixed scroll; a self-rotation preventing member interposed between the frame and the orbiting scroll for preventing a self-rotation of the orbiting scroll; and a vane making a linear movement in a radial direction of the frame according to an orbiting movement of the orbiting scroll, and forming between the frame and the orbiting scroll a second compression chamber including a spaces where the second suction and discharge opening exists.

Abstract: A vacuum pump includes an inlet port (14) and an exhaust port (86, 88). Gas from an enclosure connected to the inlet port is pumped to the exhaust port by first and second rotors (18, 52, 254) which are mounted on first and second shafts (30, 60) extending through a pump chamber (112). The rotors are connected with shaft sections (140, 150, 240, 250) which include a lobe (142, 172, 242, 242?) extending from the shaft sections and a mating channel (152, 182, 252, 252?) defined in the other. The lobes matingly engage the channels during rotation of the rotors to form a suction section (154). The suction section (154) compresses a volume of gas entering the pump from the inlet port (14) reducing the power consumed to move the volume of gas through the pump chamber more easily and increase pump efficiency.

Abstract: To improve reliability of a shaft sealing portion of a mechanical booster and simplify the structure, in a mechanical booster 1 having a motor 3 in tight contact with to a mechanical booster body 2 and rotating the shaft part 4, inserting a metal cylinder into a gap between a stator on a rotary shaft of the motor 3 and a fixed coil on the outside for partitioning stator area and a fixed coil area by the cylinder, supporting the both end of the rotary shaft of the motor 3 by bearings sealed with lubricant, and inserting a bearing fitting portion of a motor cover 30 into inside of the cylinder, the motor is sealed with a seal ring. The cylinder is made of stainless steel. A jacket water cooler is provided in the motor cover 30 around at area close to outside. The shaft part 4 of the mechanical booster body 2 is supported by bearings sealed with lubricant.

Abstract: A dry vacuum pump comprises a scroll-type vacuum pump and a rotary-vane vacuum pump, wherein the rotary-vane vacuum pump is mounted on the side of an inlet, whereas the scroll-type vacuum pump is mounted on the side of an outlet, and then a compound-type dry vacuum pump is formed by connecting and integrating the rotary-vane vacuum pump and the scroll-type vacuum pump, having the advantages of high compression ratio, high vacuuming speed, low production cost and simplified structure, thus improving the working effectiveness and quality of pumps accordingly.

Abstract: A dry vacuum pump comprises a scroll-type vacuum pump and a rotary-vane vacuum pump, wherein the rotary-vane vacuum pump is mounted on the side of an inlet, whereas the scroll-type vacuum pump is mounted on the side of an outlet, and then a compound-type dry vacuum pump is formed by connecting and integrating the rotary-vane vacuum pump and the scroll-type vacuum pump, having the advantages of high compression ratio, high vacuuming speed, low production cost and simplified structure, thus improving the working effectiveness and quality of pumps accordingly.

Abstract: A pump assembly which comprises a vane pump and a second hydraulic pump driven together with this vane pump. The vane pump has a suction region in which first pressure spaces between the vanes and second, rear pressure spaces behind the vanes become larger and a pressure region in which the pressure spaces become smaller and in which the pressure spaces are fluidically connected to a pressure outlet. This vane pump is intended particularly for supplying operating cylinders of a hydromechanical transmission of a motor vehicle with pressure fluid under relatively high pressure. The second hydraulic pump has positively driven displacement elements and is intended for supplying a circuit having a relatively low system pressure, in particular a lubricating-oil circuit of the motor vehicle, with pressure fluid.

Abstract: A plurality of rotary assemblies driven by gas pressure having internal cam activated retractable gates selectively coupled to a rotary compressor. The rotary compressor is selectively coupled through a clutch to a shaft. The shaft is rotated by the plurality of rotor engine assemblies that are driven by gas pressure. A gate is coupled to a cam follower bearing that rides on an internal surface of the rotor housing, causing the gates to form chambers within the rotor as well as move out of position to pass a chamber divider. The shaft may be coupled to a load to do work.

Abstract: A compound vacuum pump incorporating a screw mechanism section. The screw mechanism section comprising two externally threaded rotors mounted on respective shafts in a pump body. The rotors are adapted for counter-rotation in a first chamber within the pump body with intermeshing of the rotor threads to pump gas by action of the rotors. The root diameter of each rotor increases and the thread diameter of each rotor decreases in a direction taken from pump inlet and in which the gas is pumped. The pump additionally incorporates a roots mechanism section comprising two roots-type profile rotors also mounted on the respective shafts and adapted for counter-rotation in a second chamber within the pump body situated at an inlet end of the pump.

Abstract: A pump or motor having a three-lobed rotor capable of being used within a hypocycloidal two-lobed stator that is designed primarily for use with a one-lobed rotor. The three-lobed rotor design allows for interchangeability with the two-lobed stator to provide for varying fluid displacements to meet particular demands. A specific application allows for the combination of both the three-lobed rotor along with a one-lobed rotor within the same two-lobed stator, thereby improving the efficiency of the pump or motor.

Abstract: A compound gear pump includes an internal gear pump including an outer rotor having on the outer periphery external teeth, an external gear pump including a rotor having on the outer periphery an external teeth circumscribed with the external teeth of the outer rotor, and a guide face arranged on the outer periphery of the outer rotor and being adjacent to the external teeth of the outer rotor in the axial direction thereof.

Abstract: Vacuum pumping apparatus includes a non-scroll type auxiliary pump and a scroll pump disposed in a single housing. The auxiliary pump and the scroll pump are connected in series and are driven by a common motor. Typically, the auxiliary pump has a relatively high pumping speed and the scroll pump has a relatively high compression ratio. The auxiliary pump may be a regenerative blower, a roots-type blower or a screw-type blower. When a co-rotating scroll pump is utilized, a regenerative blower may be formed at or near the outer periphery of a disk on which the non-orbiting scroll blade is mounted. In another configuration, first and second scroll pumps are disposed within a housing. The scroll blade sets of the first and second scroll pumps have different orbiting radii. Scroll pump leakage may be reduced by forming a closed-loop seal around the inlet region of the scroll pump and connecting the inlet region to an intermediate pressure.

Abstract: A mechanical vacuum pump having mounted in each of at least three pumping chambers a pair of intermeshing rotors. A first rotor of each pair being mounted for rotation on a first shaft passing through the chambers and a second rotor of each pair being mounted for rotation on a second shaft passing through the chambers. The first and second shafts are driven in contra-rotating directions to effect a sequential pumping action by the pairs of rotors in each chamber in respect of gas being pumped between a pump inlet and a pump outlet. The pump possesses at least one chamber with claw-type profile rotors and one ore more chambers with roots-type profile rotors. The chamber nearest the pump outlet has a rotor with a roots-type profile.

Abstract: In a screw fluid machine including male and female rotors which are engaged with each other, a casing for accommodating both the male and female rotors, fluid working rooms which are formed by the male and female rotors and the casing, and fluid inlet and outlet ports which are provided in the casing so as to intercommunicate with one end portion and the other end portion of the working rooms, the helix angle of the screw gear constituting each of the male and female rotors is set to be continuously varied in a helix advance direction. Further, the screw gear is designed so that the peripheral length of a pitch cylinder in a helix advance direction on a development of a tooth-trace rolling curve on the pitch cylinder of the screw gear can be expressed by a substantially monotonically increasing function.

Abstract: A first pump includes inner and outer intermeshing rotors, the outer rotor formed with external gear teeth. A second pump includes inner and outer meshing rotors, the outer rotor of the second pump having teeth continually engaged with the external teeth of the first pump outer rotor. The inner and outer rotors are formed with mutually intermeshing lobes that define between them pumping chambers through which hydraulic fluid is moved from a suction inlet to a pressurized outlet. A third pumping element includes pumping chambers located in the spaces between the intermeshing involute gear teeth on the outer rotors of the first and second pumps. A passage plate defines suction and pressure passages, which carry hydraulic fluid from a reservoir or sump to outlet ports, through which fluid is supplied to the hydraulic system.

Abstract: A composite dry vacuum pump of this invention has closed chambers accommodating a pair of screw rotors and a pair of roots rotors respectively mounted coaxially to the front ends of the screw rotors. The roots rotors and the screw rotors are rotated at the same speed in opposite directions by a motor to aspirate fluids from a suction port on one end wall and discharge the fluid through a discharge port on the outer surface of the other end wall. The characteristics of power requirement of the portion of the roots rotors and that of the portion of the screw rotors changes inversely to the suction port pressure variation, therefore the characteristic of the total power requirement of the pump of this invention is almost flat over the all pressure range and the motor having smaller output power can operate the pump according to the present invention.

Abstract: A combined compressor and pump has two parallel shafts journalled in a housing having a compressible fluid inlet and a compressible fluid outlet. Rotors are mounted on each of the shafts for forming a roots type compressor and compressing fluid from the compressible fluid inlet. One shaft of the compressor, which forms a supercharger for an engine, is driven by the engine, and the other shaft is driven in synchronization therewith by a pair of meshing gears mounted on the shafts, the meshing gears being constructed so as to form a gear pump. A coolant circulates within a coolant jacket in the housing and is circulated by the gear pump. The heated coolant may be circulated through a closed loop including a heat exchanger and a bypass passage for bypassing the heat exchanger during low temperature operating conditions.

Abstract: A rotary vane vacuum pump assembly is disclosed which is characterized by the absence of the discharge of lubricating oil with the exhaust airstream, and which includes an internal stator and a surrounding rotor. Pivotal vanes are mounted on the interior of the rotor, so as to define a plurality of air chambers which expand and contract as the rotor rotates about the stator. Also, a freely rotatably cylindrical sleeve is positioned between the stator and vanes, so that the relative sliding contact of the vanes on the surface of the sleeve is minimized, to thereby eliminate the need for internal oil lubrication. In one preferred embodiment, a hydraulic pump is joined to the vacuum pump to form a compact assembly, and wherein the hydraulic pump supplies oil to the bearings which mount the rotor.