The pump housing includes a pair of sliding surfaces clamping the outer and inner gears from both their sides to allow both the gears to slide on the sliding surfaces, a suction port part suctioning fuel from outside into inside of the gear accommodation chamber, and a discharge port part discharging fuel from inside into outside of the gear accommodation chamber. At least one of the suction port part and the discharge port part includes an elongated groove that is depressed from the corresponding sliding surface and extends along a circumferential direction of the pump housing in a region opposed to the pump chambers, opening bores that open on the elongated groove from outside of the gear accommodation chamber, and ribs each of which is arranged between the corresponding adjacent two opening bores. The opening bores and the ribs are arranged alternately along an extending direction of the elongated groove.

The present disclosure provides a compressor and an air conditioner. The compressor includes a housing; a first rotating shaft mounted in the housing; a connecting assembly sleeved on the first rotating shaft; and a first rotor assembly including a first rotor and a second rotor coaxially disposed on the connecting assembly. The connecting assembly carries the first rotor and the second rotor to rotate about the first rotating shaft together. The connecting assembly is configured to limit the relative positions of the first rotor and the second rotor, such that there exists a clearance between the first rotor and the second rotor. The present disclosure can maintain a clearance between the first rotor and the second rotor without increasing the number of components of the compressor.

Provided is a scroll compressor. The scroll compressor may be provided with at least one refrigerant accommodating groove recessed to a preset depth in at least one from a side surface of a fixed wrap constituting a compression chamber and a side surface of an orbiting wrap. Thus, a volume of the compression chamber in a discharge area may be increased in correspondence with a volume of the at least one refrigerant accommodating groove, and a space into which liquid refrigerant, etc. may escape may be ensured to resolve excessive compression in the compression chamber. Then, a stress exerted on the fixed wrap is reduced, and a damage to the fixed wrap due to pressure in the compression chamber may be suppressed.

A screw compressor for compressing a working medium sucked through a suction opening and discharging the compressed working medium through a delivery opening, wherein the screw compressor includes: a male rotor and a female rotor that rotate while meshing with each other; a casing that houses the male rotor and the female rotor and is provided with a bore which forms a working chamber designed, together with the male rotor and the female rotor, to compress the working medium; a drive unit that rotationally drives at least one of the male rotor and the female rotor; a working chamber closing unit that forms a suction port for sucking the working medium into the working chamber and closes the working chamber when the working chamber reaches a specified capacity; and a suction space that connects the suction opening and the suction port to allow communication therebetween, wherein an open space that connects the suction opening and the suction port to allow communication therebetween is provided between a shaft of the male rotor and a shaft of the female rotor on an opposite side of the male rotor and the female rotor relative to the suction port.

This invention discloses an improved rotary vane vacuum pump. The vacuum pump includes an enlarged inlet port which is spread over the width and length of the stator in a zig-zagging fashion within which the vanes pass. In one embodiment, the inlet port describes an inverted W shape in the stator and includes appropriately placed ribs to ensure the stator does not deform around the inlet port.

A screw compressor for a utility vehicle has an air filter with an intake port and an air supply channel for supplying air to the screws of the screw compressor. The intake port is arranged between the air filter and the air supply channel and includes a pocket groove which can maintain the oil.

A first plate portion covers one opening of a pump chamber of a tubular portion, and a second plate portion covers the other opening of the pump chamber along a center axis of the tubular portion. A hole forming portion is equipped to an outside of the tubular portion to form a connection hole. A length of the hole forming portion along the center axis is less than or equal to a length of the tubular portion along the center axis. A first imaginary line connects a center of an outer opening of the connection hole with a point on the center axis. The first imaginary line intersects perpendicularly with the center axis. A length of the connection hole in a direction perpendicular to both the first imaginary line and the center axis is greater than a length of the connection hole along the center axis.

A vane pump includes: a suction port configured to guide working oil to a pump chambers; a discharge port configured to guide the working oil discharged from the pump chambers; and a notch formed from an opening edge portion of the suction port towards a reversing direction of a rotation direction of a rotor, wherein the pump chambers each communicates with the suction port through the notch during a course of the transition from the state, in which the pump chamber is in communication with the discharge port, to the state, in which the communication with the discharge port is shut off, as the rotor is rotated.

A screw compressor element with a housing and two screw rotors that are affixed in the housing in a double cylindrical chamber provided to this end, whereby the housing is provided with an inlet opening on the inlet side of the screw compressor element, whereby the inlet opening extends in the cylindrical walls of the double cylindrical chamber with at least a section that extends in an axial direction, and a transverse section connecting thereto in the form of a strip that extends from the axial section on the inlet side to a side of the section in a direction transverse to the axial direction.

A suction passage includes: a first passage that is cylindrical and connected to a suction unit; and a second passage whose one end is connected to the first passage and other end has an opening on the inner circumference of a cylinder. The second passage is formed, from its one end to the other end, in a slit-like shape penetrating the upper side and the lower side of the cylinder, and satisfies LW1, W1D10.7, W2D1 where the width of the second passage at the other end in a circumferential direction of the cylinder is W1, the width of the second passage at the one end is W2, the length of the second passage from the one end to the other end is L, and the inner diameter of the first passage at an area connected to the second passage is D1.