Abstract: A scroll fluid machine comprises a stationary scroll that has a spiral stationary wrap, and an orbiting scroll that has a spiral orbiting wrap to form a compression chamber between the stationary and orbiting wraps. In the stationary and orbiting wraps, an outer low-pressure pressurizing portion is separated from an inner high-pressure pressurizing portion. A plurality of outlets and inlets are formed in the low-pressure and high-pressure pressurizing portions respectively. At least one of the outlets or at least one of inlets is selectively closed.

Abstract: To provide a gas compressor in which fretting wear due to vibration of an oil separation filter is prevented to thereby achieve an improvement in durability. A gas compressor is provided with a press-fixing unit for press-fixing end portions of an oil separation filter.

Abstract: A scroll compressor having a hybrid wrap is defined to have its wrap origin offset from a drive center of both the orbiting and non-orbiting scroll members. The offset is selected in a direction such that it eliminates extremes in the torque curve relative to shaft rotation. In this way, torque reversal is generally eliminated.

Abstract: A discharge pulsation reducing cooler B is provided to cover the circumferential periphery of a compressor A. The discharge pulsation reducing cooler B has a delivery passage 41 and a jacket 43 covering that, and cooling water is circulated through a passage formed between the delivery passage 41 and the jacket 43. Delivered air flowing through the delivery passage 41 is cooled by the cooling water. In particular, because heat exchange efficiency is promoted by turbulence caused by the pulsation in the delivery passage 41, the delivered air is cooled efficiently. Also, pulsation is reduced in first and second expansion chambers 44, 45 in the delivery passage 41, and pulsation noise in the delivery passage 41 is reduced by the cooling water passage 42 and the jacket 43.

Abstract: The pump for generating pressure or negative pressure comprises a pump chamber (32) which has a high-pressure port and a low-pressure port. Two rotors (28, 30) having at least two blades are fitted to two parallel shafts (20, 22) in the pump chamber (32) that are offset to each other, the shafts defining an axial direction. A drive (10) is arranged on an end face of the rotors (28, 30) and a housing cover (34) is arranged on the opposite side. The housing cover (34) is configured cup-shaped and the high-pressure port (42) as well as the low-pressure port (40) are integrated in the housing cover (34). The inner wall (44) of the housing cover (34) delimits the pump chamber (32) on an end face and has two axial openings (46, 48) one each adjoining by one channel (40, 42) which is integrated in the body of the housing cover (34). The axial opening (48) for the high-pressure port, in operation of the pump, is covered by one of the rotors (28, 30) for a time to enable inner compression of the delivered medium.

Abstract: An adjustable fixed displacement vane pump is disclosed which includes a pump housing defining an interior pumping chamber having a central axis extending therethrough, a rotor member mounted for rotational movement within the interior pumping chamber of the pump housing about an axis aligned with the central axis of the interior pumping chamber, the rotor member having a central vane section with a plurality of circumferentially spaced apart radial vane slots formed therein, each vane slot supporting a corresponding vane element mounted for radial movement therein, and each vane element having an outer tip surface, a cam member mounted for pivotal movement within the interior pumping chamber of the pump housing about a fulcrum axis extending parallel to the central axis of the rotor member, the cam member defining a cam body having a circular bore extending therethrough for receiving the rotor member, the circular bore forming a cam chamber defining a cam surface making continuous contact with the outer tip

Abstract: The invention comprises an arrangement for controlling the flow of a coolant fluid in a compressor, in particular in a rotary compressor, in which a coolant-fluid inlet for coolant fluid discharged from the compressor and a coolant-fluid outlet for returning the coolant fluid into the compressor are provided. A fluid cooler is also provided through which, when necessary, part of the coolant fluid can be directed for cooling and a system-control actuator is used to control the magnitude of the proportion of the coolant fluid that is directed through the fluid cooler on the basis of system parameters, in particular on the basis of the temperature of the coolant fluid.

Abstract: In a valve used in connection with a scroll compressor, a central profiled body is designed to protrude in an opening for outlet of gas from a compression stage, a outer axisymmetric surface of which is concave, of generally toroidal shape, and is terminated by a tip, the outlet opening of the compression stage being delimited by a curved surface forming, in the downstream direction, a widening providing, with the central profiled body, a cross section for the passage of the gas which is substantially constant, closing means being provided in order to seal this passage in the closed position of the valve.

Abstract: An eccentric screw pump or motor which includes; stators (3) having an elastic flexible coatings (32) which forms a helical bore with teeth (37) and tooth gaps (38) and a rotor (4) disposed for rolling movement in the bore and being formed with teeth (35) and tooth gaps (36) which are engageable with the stator bore. To enhance performance over a wider range of operating temperatures, the bore defined by the elastic flexible coating is formed with a plurality of waves (4) and grooves (39) which, like the teeth (37) and tooth gaps (38) of the bore are helical, but which have dimensions in both the circumferential and radial directions that are smaller than the dimensions of the teeth (37) and tooth gaps (38) of the bore.

Abstract: A variable capacity rotary compressor includes a housing having a cylindrical compressing chamber defined therein, a rotating shaft having an eccentric body part which rotates in the compressing chamber, a ring piston fitted over the eccentric body part of the rotating shaft so as to have the ring piston rotate while being in contact with an inner surface of the compressing chamber, a vane mounted in the housing so as to have the vane advance or retract in a radial direction of the compressing chamber in accordance with a rotation of the ring piston, and a control unit which is connected to the vane and moves in opposite directions in response to pressures of a refrigerant inlet and a refrigerant outlet of the compressor, so as to control a moving range of the vane. Accordingly, a simpler construction of the compressor is achieved and a refrigerant compressing capacity is easily controlled.

Abstract: A scroll-type fluid machine includes a fixed scroll having spiral-form fixed wraps standing on one side face and an orbiting scroll having spiral-form orbiting wraps standing on one side face facing the fixed scroll. The orbiting scroll is set up on a drive shaft so as to be able to orbit. A sealed chamber is formed between the fixed wraps and the orbiting wraps. In the sealed chamber an outer sealed chamber and an inner sealed chamber are defined by an annular partition provided on either the fixed scroll or the orbiting scroll. The outer sealed chamber includes outer inlets on the outside and an outer outlet on the inside, and the inner sealed chamber includes an inner inlet on the outside and an inner outlet in the center. A gas that has been taken in via the outer inlets is compressed and discharged via the outer outlet, and a gas that has been taken in via the inner inlet is compressed and discharged via the inner outlet.

Abstract: A compressor is driven by a drive shaft rotatably supported by a main bearing housing and a lower bearing housing. The main bearing housing positions a main bearing at or near a nodal point of the drive shaft during vibration by the drive shaft. The main bearing housing is designed such that the main bearing pivots during the vibration of the drive shaft in order to maintain surface contact between the bearing and the drive shaft to eliminate edge loading of the bearing.

Abstract: A scroll compressor is provided with a hybrid having thicker wrap portions and thinner wrap portions. The problem of uneven thermal expansion is addressed by providing a recess in the thicker portion. The recess communicates with the inner higher pressure and higher temperature compression chambers to communicate the higher temperature refrigerant along the face of the thicker portion. The recess blocks flow of this refrigerant to the radially outer end of the thicker portion which communicates with a lower pressure/lower temperature chamber. The use of the recess compensates for uneven thermal expansion by bringing the thicker portion to a more even temperature across its width.

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

Abstract: Scrolls made from one or more near-net shaped powder metal processes either wholly or fabricated together from sections. Both “conventional” press and sinter methods and metal injection molding methods will be described.

Abstract: A screw compressor including a housing having a discharge port; a plurality of rotors including at least one male rotor and at least one female rotor rotatably disposed in the housing for generating a discharge flow through the discharge port, the discharge port having a radial portion and an axial portion, wherein the discharge port is positioned relative to the plurality of rotors so that the radial portion opens prior to the axial portion whereby kinetic energy in the discharge flow can be recovered.

Abstract: The present invention provides a multi-stage vacuum pump which includes: a housing in which a plurality of pumping chambers are formed, the pumping chambers being arranged in series and being in fluid communication with one another, one of the pumping chambers which is at one end of the series acting as an initial stage pumping chamber, another of the pumping chamber which is at the other end of the series acting as a final stage pumping chamber, the housing being provided with an inlet port for sucking a gas from a space to be evacuated into the initial stage pumping chamber, the housing being provided with an outlet port for exhausting the gas from the final stage pumping chamber; Roots-type pump sections occupying the respective pumping chambers, each of the Roots-type pump sections having a pair of intermeshed Roots-type profile rotors; and a pair of shafts adapted for rotation within the housing about their lengthwise axes in contra-rotational direction, the pair of shafts being secured to the respective

Abstract: A hydraulic motor 10/110/210 has an end cover 12/112/212 including a first port 14/114/214 and a second port 16/116/216, and a gerotor drive assembly 18/118/218 which hypocycloidally moves a drive link 22/122/222. The motor's flow circuit comprises a working path (e.g., for providing rotational motion) from the end cover 12/112/212, through the drive assembly 18/118/218 and back to the end cover 12/112/212. Bolts 26/126/226 extend through registered openings in the end cover 12/112/212, the drive assembly 18/118/218 and a housing 20/120/220 and the bolts 26/126/226 are positioned in a circular array outside the motor's pressure vessel whereby the motor 10/110/210 has a “dry bolt” design. The motor's flow circuit can also comprises a non-working path (for cooling, lubrication and/or sealing purposes) which circulates fluid through chambers surrounding the drive train components.

Abstract: The invention is related to a toothed rotor set for a pump or engine consisting of a rotating outer rotor, which has an approximately star-shaped bore. The bore has a fine inner tooth system and an inner rotor aligned eccentrically inside it. The inner rotor has oil pockets for planetary gears. The planetary gears also have a fine tooth system with the help of which they roll on the fine teeth of the outer rotor. The planetary gears thus build a tooth system that translates into an outer tooth system. The outer tooth system has one tooth less than the inner tooth system of the outer rotor.

Abstract: The present invention involves a gear assembly having a lifting feature for a fuel pump for supplying fuel to an automotive engine from a fuel tank. The gear assembly comprises an inner gear and an outer gear in mating relationship with the inner gear. The inner gear has a substantially disc shape with an outside camming surface and having an inner cover face and an inner body face. The inner gear has a center aperture formed therethrough defining an axis of rotation perpendicular to the inner cover and inner body faces. The inner cover face has a plurality of inner concave grooves radially formed thereon and spaced apart from each other to provide lifting of the inner gear when rotating about the axis. The outer gear has a substantially planar shape. The outer gear includes an annular wall having an inside camming surface slideably engaging about the outside camming surface to matingly cooperate with the inner gear for rotation about the axis.