A device usable as an impeller has a plurality of vanes rotating eccentrically about a shaft. Eccentric rotation is enabled by a cam mounted on the shaft. The vanes are received within slots in a rotor which surrounds the shaft and rotates about an axis coaxial with the shaft. The rotor rotates within a housing having a cylindrical surface facing the rotor. The surface is eccentric to the shaft. The vanes execute reciprocal motion upon rotation of the rotor. The vane motion is constrained so that the edges of the vanes remain proximate to the cylindrical surface during rotation.

A concentric rotary fluid machine includes a first body and a second body that are rotatable relative to each other and coaxially arranged one inside the other. A plurality of gates are supported by the second body in gate pockets. Each gate pocket includes: a gate retention recess that receives a gate cylinder of a gate; a gate seal recess that receives a sealing portion of a gate; and an intervening land. The sealing portion is configured to reciprocate up and down within a corresponding gate seal recess while maintaining contact with the recess and the second body. A plurality of lobes on the first body cause the gates to swing about respective swing axes as the first body rotates relative to the second body. The lobes and the lands are configured so that a lobe forms a substantial seal against a land when in mutual radial alignment.

A pump, particularly a vacuum pump for boosting braking power on a motor vehicle, including a housing, a rotor mounted in the housing so as to be rotatable, an oil riser groove arranged in the housing in the area of the rotor mounting, and a transverse bore arranged in the rotor transverse to the longitudinal axis of the rotor and which can be connected to the oil riser groove. The rotor mounting area is connected to an oil supply bore. The transverse bore interacts with an axial bore in the rotor which leads to a coupling section within the rotor, in which a coupling is arranged which can be engaged by a fastener having a central bore running parallel to the longitudinal axis of the rotor.

Disclosed herein is a vane rotary compressor in which a fluid such as a refrigerant is compressed while a volume of a compression chamber is reduced during rotation of a rotor. There is provided a vane rotary compressor capable of preventing a delay of rotation operation of a vane by respectively forming oil films on both sides of a hinge portion of the vane in a rotation direction thereof and smoothly sliding the hinge portion.

The robustness of refrigerant against disproportionation reactions is improved. A method uses, as refrigerant for a compressor, a composition that contains one or two or more selected from a group of ethylene-based fluoroolefins, 2,3,3,3-tetrafluoropropene (HFO-1234yf), and 1,3,3,3-tetrafluoropropene (HFO-1234ze), in which the compressor includes a discharge pipe made of metal having a greater heat capacity than a discharge pipe of a compressor that uses R32, R410A, R134a, or R404A as refrigerant, or a casing that includes an intake pipe connection section made of metal having a greater heat capacity than an intake pipe connection section of a casing of the compressor that uses R32, R410A, R134a, or R404A as refrigerant.

A compressor includes a member with a recess in which a reed discharge valve is disposed. The recess has a discharge hole, a fixation hole, and an annular projection formed around the discharge hole. The discharge valve includes a fixed portion, a flexible portion, and a head portion to open/close the annular projection. A protruding portion is formed at a rear end portion of the fixed portion. A first side surface of the protruding portion is designed to be substantially flush with a side surface of the fixed portion, which surface is closer to a center of the member. When the discharge valve rotates in a predetermined direction about the fixation hole after the discharge valve is disposed in the recess but before being fixed to the member, the first side surface of the protruding portion comes into contact with a side wall of the recess.

A device usable as an impeller has a plurality of vanes rotating eccentrically about a shaft. Eccentric rotation is enabled by a cam mounted on the shaft. The vanes are received within slots in a rotor which surrounds the shaft and rotates about an axis coaxial with the shaft. The rotor rotates within a housing having a cylindrical surface facing the rotor. The surface is eccentric to the shaft. The vanes execute reciprocal motion upon rotation of the rotor. The vane motion is constrained so that the edges of the vanes remain proximate to the cylindrical surface during rotation.

A compression mechanism that can suppress generation of galling and seizure is provided. The compression mechanism includes a bush 60 including a first sliding surface 61 sliding with an inner surface 45a of a bush hole 45 and a second sliding surface 63 sliding with a side surface 52a of a blade of a piston, and includes at least one of a first bulge 62 formed on one of the first sliding surface 61 and the inner surface 45a such that a gap X between the first sliding surface 61 and the inner surface 45a gradually decreases toward a direction in which lubricant Y is drawn between the first sliding surface 61 and the inner surface 45a along with rocking of the bush 60, and a second bulge 64 formed on the second sliding surface 63 such that the gap X between the second sliding surface 63 and the side surface 52a gradually decreases toward a direction in which the lubricant Y is drawn between the second sliding surface 63 and the side surface 52a along with forward and backward movement of the blade.

A compression mechanism that can suppress generation of galling and seizure is provided. The compression mechanism includes a bush 60 including a first sliding surface 61 sliding with an inner surface 45a of a bush hole 45 and a second sliding surface 63 sliding with a side surface 52a of a blade of a piston, and includes at least one of a first bulge 62 formed on one of the first sliding surface 61 and the inner surface 45a such that a gap X between the first sliding surface 61 and the inner surface 45a gradually decreases toward a direction in which lubricant Y is drawn between the first sliding surface 61 and the inner surface 45a along with rocking of the bush 60, and a second bulge 64 formed on the second sliding surface 63 such that the gap X between the second sliding surface 63 and the side surface 52a gradually decreases toward a direction in which the lubricant Y is drawn between the second sliding surface 63 and the side surface 52a along with forward and backward movement of the blade.

A gas compressor comprises a rotor having vane grooves, a cylinder shaped to surround an outer circumference of the rotor, vanes plate-shaped, slidably inserted into the vane grooves, and abuttable at one ends on the inner circumference of the cylinder, upon receiving a back pressure from the vane grooves, two side blocks to enclose both ends of the rotor and the cylinder, respectively, compression chambers supplied with a medium to compress the medium to a high-pressure medium for discharge, an oil separator to separate, from the discharged high-pressure medium, oil to be used as the back pressure, an oil path through which the oil at a certain pressure is supplied to the vane grooves, and a high-pressure supply hole formed in at least one of the side blocks, including a small diameter portion and a large diameter portion integrally formed.