Abstract: In a scroll compressor that can switch between an internal high-pressure operation and an internal low-pressure operation, in order to provide proper back pressure for an orbiting scroll during either operation, a back pressure chamber of the orbiting scroll is divided by means of a first and a second thrust rings into a first back pressure chamber in communication with a driving chamber and an independent second back pressure chamber, and the pressure in the second back pressure chamber is set at discharge pressure or suction pressure depending on an operation mode.

Abstract: In a scroll compressor that can switch between an internal high-pressure operation and an internal low-pressure operation, in order to provide proper back pressure for an orbiting scroll during either operation, a back pressure chamber of the orbiting scroll is divided by means of a first and a second thrust rings into a first back pressure chamber in communication with a driving chamber and an independent second back pressure chamber, and the pressure in the second back pressure chamber is set at discharge pressure or suction pressure depending on an operation mode.

Abstract: A fluid compressor comprises a rotary member, a cylinder, and a closed casing for receiving the rotary member and cylinder. The rotary member and cylinder are relatively turned so that a fluid is drawn into work chambers through a suction port, successively compressed and conveyed toward a discharge port through the work chambers, and discharged outside. The fluid compressor is provided with a control valve means. When pressure in the work chambers exceeds a predetermined value during the compressing process, the control valve releases the pressure through a discharge or suction end of the cylinder, or to the inside of the casing.

Abstract: A scroll compressor comprises a first end member having an axis, a second end member facing the first end member, relatively movable crosswise of the first end member and having an axis, a bearing portion extending through either one of central portions of the first and second end members, a first scroll wrap formed in a vortical manner and extending from the face of the second scroll end member, the first scroll wrap having an inner end portion and an inner face, a second scroll wrap formed in a vortical manner and extending from the face of the second end member so as to interdigitate with the first end member, the second scroll wrap having an outer end portion and an inner face, a low gas pressure chamber and a high pressure chamber formed around or in the first and second end members, compressing chambers defined between the first and second scroll wraps, and engaging portions formed on the inner portions of the first and second scroll wraps and each having a guide face, the guide faces of the first and s

Abstract: A gas compressor comprises a fixed scroll member and a movable scroll member. A plurality of crescent working chambers are defined between the scroll members so that the volume of the working chambers varies when the scroll members are relatively moved. The compressor has a container which seals a power source and the scroll members and forms inner spaces therebetween. An intake port for drawing a gas from the exterior of the container into the working chambers is formed in the outer peripheral region of the fixed scroll member, and an axial port is formed in the inner region of the fixed scroll member so that the working chambers communicates therewith.

Abstract: A piston is eccentrically arranged in a cylinder along its axial direction and can be rotated relative to the cylinder. Part of the piston is in contact with the cylinder's inner surface. First and second helical grooves are formed in the piston's outer surface and separated at its central portion, the pitches of the grooves being gradually increased from both end portions to the center portion of the piston. First and second blades are inserted in first and second grooves so as to be moved in and out of the grooves with the outer edges of the blades contacting the inner surface. The blades partition a space between the cylinder and the piston into a plurality of operation chambers with volumes corresponding to the gradual pitch increases.

Abstract: A fluid compressor includes a cylinder and a columnar rotary rod. The rod is arranged in the cylinder so as to extend in the axial direction thereof and be eccentric thereto, and orbitable relative to the cylinder without rotation with respect to the cylinder while part of the rod is in contact with the inner circumferential surface of the cylinder. A spiral groove is formed on the outer circumference of the rod and a spiral blade is fitted in the groove. The space between the outer circumference surface of the rod and the inner circumference surface of the cylinder is divided by the blade into a plurality of operating chambers. The groove has an overall length larger than that of the blade by a predetermined length so that the blade is displaceable relative to the rod in the radial and circumferential directions of the rod without sliding on the inner circumferential of the cylinder.

Abstract: A scroll member comprising a metallic end plate having a spiroidal groove on one side thereof, and a through-hole communicating with the groove, and a resin wrap joined to the groove of the end plate so as to protrude from the surface of the end plate. The wrap being formed by injection molding, and the through-hole and the groove being filled with part of the wrap.