Abstract: A variable capacity vane compressor has an annular control element angularly displaceably received within an annular recess formed in one of side blocks defining a cylinder. The control element is angularly displaced in response to a difference in pressure between first and second pressure chambers formed in the one side block and communicating with a zone under lower pressure and a zone under higher pressure, respectively, and to the biasing force of a biasing member, thereby varying the opening angle of at least one second inlet port formed in the one side block and hence controlling the capacity of the compressor.

Abstract: An air conditioning system includes an evaporator and a variable capacity compressor. The compressor has a lower pressure zone including a suction chamber connected to the outlet of the evaporator, a higher pressure zone, a bellows displaceable in response to pressure representative of a thermal load on the system, a control valve device responsive to displacement of the bellows for bringing the higher pressure zone into and out of communication with the lower pressure zone to thereby control the difference between pressure from the higher pressure zone and pressure from the lower pressure zone, and a control element responsive to change in the difference between pressure from the higher pressure zone and pressure from the lower pressure zone for varying the delivery quantity of the compressor.

Abstract: A variable capacity compressor including a pumping device, and a control element the position of which can be changed to determine the capacity of the pumping device. The compressor comprises: a detector for detecting change in the position of the control element in a continuous manner; and a capacity-indicating device for visually indicating an output value thereof in a manner continuously variable in response to a continuous change in output from the detector, whereby the output value visually indicated by the capacity-indicating device varies continuously with a continuous change in the capacity of the pumping device.

Abstract: A variable displacement compressor includes a lubrication oil supply passage defined in a side block for interconnecting a displacement adjustment mechanism disposed in the side block and a high pressure oil sump defined in the side block. With this lubrication oil supply passage, a sufficient lubrication of the displacement adjustment mechanism is achieved.

Abstract: A variable capacity vane compressor having compression spaces defined between a cylinder and a rotor at diametrically opposite locations. A control element rotatably arranged in the cylinder, which has two cut-out portions circumferentially extending at diametrically opposite locations through which inlet ports and respective corresponding compression spaces are communicatable with each other. The cut-out portions are disposed relative to the respective corresponding compression spaces such that compression commences in each of the compression spaces when a trailing vane passes a forward end edge of a corresponding cut-out portion with respect to the rotation of the rotor. The control element is rotatable between a partial capacity position and a full capacity position for varying the capacity of the compressor.

Abstract: A variable capacity vane compressor has an annular control element angluarly displaceably received within an annular recess formed in one of side blocks defining a cylinder. The control element is angularly displaced in response to a difference in pressure between first and second pressure chambers formed in the one side block and communicating with a zone under lower pressure and a zone under higher pressure, respectively, and to the biasing force of a biasing member, thereby varying the opening angle of at least one second inlet port formed in the one side block and hence controlling the capacity of the compressor.

Abstract: A variable capacity type compressor in which a control element is mounted in one of side blocks formed with inlet ports for rotation about its own axis in opposite circumferential directions between a first extreme position providing the maximum capacity of the compressor, and a second extreme position providing the minimum capacity of the compressor, to vary the compression starting timing. The control element has cut-out portions through which compression medium is drawn into compression spaces, of which one upstream end with respect to the direction of rotor rotation determines the compression starting timing in cooperation with vanes passing same. The cut-out portion is formed of first and second portions circumferentially arranged.

Abstract: In a sliding-vane rotary compressor, one of the opposite open ends of a cylinder is closed by a first head, the other open end being closed by a side block to which is secured a second head so as to define jointly with the side block a low pressure chamber and a high pressure chamber. With this construction, one side block can be omitted and hence the number of structural components is reduced. Preferably, a displacement adjustment mechanism is incorporated in the side block and the second head for adjusting the displacement of the compressor.

Abstract: A variable capacity vane compressor has a cylinder including a cam ring having an inner peripheral surface with an oblong cross section and within which a rotor is rotatably received, a plurality of vanes carried by the rotor, and a control plate disposed in the cylinder for rotation in opposite circumferential directions and having a peripheral edge formed with at least one cut-out portion. The control plate is disposed to rotate in response to a difference between pressure from a lower pressure zone and pressure from a higher pressure zone to cause a change in the circumferential position of the cut-out portion, thereby varying the compression commencing timing of the compressor and hence the capacity of same.

Abstract: A sliding-vane rotary compressor includes a recess defined in a cylinder and to which a discharge hole is open, a cover secured to the cylinder to close the recess, a discharge valve disposed in a valve receiving chamber defined between the cover and the cylinder, and a discharge connecting hole extending in the cylinder and a side block for connecting the interior space of the recess and a high pressure chamber. The compressor thus constructed is simple in size and light in weight due to non-inclusion of a shell which is required in the conventional compressor. Preferably, a displacement adjustment mechanism is incorporated in the compressor for adjusting the displacement of the latter.

Abstract: A variable capacity vane compressor in which one of front and rear side blocks has at least one inlet port divided into first and second portions, and a control element has at least one pressure-receiving protuberance dividing a space formed in the one side block into first and second pressure chambers, wherein the control element angularly moves in response to a differential pressure between the first and second pressure chambers, to vary the opening angle of the second portion of the at least one inlet port. A torsion coiled spring is fitted around a hub of the one side block for biasing the control element in a circumferential direction of increasing the opening angle of the second portion of the inlet port. The torsion coiled spring has an end thereof provided with a first engaging portion engaging a first retaining device provided in the control element, and another end thereof provided with a second engaging portion engaging a second retaining device provided in the hub, through a holding device.

Abstract: A cylinder has at least one valve seating surface-forming portion which has an outer surface formed therein with at least one recess, the bottom surface of which serves as a valve seating surface. A discharge valve is arranged on the outer surface of the valve seating surface-forming portion to close or open outlet holes formed in respective ones of the valve seating surface at locations where the wall thickness of the cylinder is the minimum. The discharge valve has at least one elastic valve body having an arcuate cross section and disposed in tight contact with a corresponding one of the valve seating surface. The valve seating surface is arcuately concavely cured with almost the same radius of curvature as that of the valve body of the discharge valve.

Abstract: A variable capacity vane compressor comprising a control element having at least one pressure-receiving protuberance dividing a space into a first and a second pressure chamber, wherein the control element angularly moves in response to a differential pressure between the first and second pressure chambers, to vary an opening angle of a second portion of at least one inlet port. The control element has mounted thereon a sealing member for sealing between the first and second pressure chambers and between a low pressure chamber and a vane back pressure zone.

Abstract: A variable capacity vane compressor comprises additional refrigerant inlet ports formed in one of front and rear side blocks of a cylinder accommodating a rotor, and communicating a suction chamber with a compression chamber on a suction stroke, and a control element received in a recess formed in an end face of the above one side block facing the rotor, for rotation to vary the opening angle of the additional inlet ports to thereby control the compression commencing timing of compression medium. At least one spacer is interposed between the control element and at least one of the above one side block and the rotor, for maintaining a predetermined minimum clearance therebetween.

Abstract: A variable capacity vane compressor has a pressure chamber formed in one of side blocks of a cylinder and communicating a zone under lower pressure with a zone under higher pressure, and at least one second inlet port the opening angle of which is variable in response to a difference between pressure within a first pressure chamber of the pressure chamber and pressure within a second pressure chamber of same. The second pressure chamber is communicated with the zone under higher pressure via a high-pressure communication passage and with the zone under lower pressure via a low-pressure communication passage.

Abstract: The endless camming inner peripheral surface of the pump housing, which performs one cycle of suction, compression and discharge of fluid in cooperation with the vanes and the rotor, has a cam profile including an increasing radius portion along which the amount of protrusion of each vane from the rotor gradually increases with movement of the vane, and a decreasing radius portion along which the amount of protrusion of each vane from the rotor gradually decreases with movement of the vane. The increasing radius portion and the decreasing radius portion are continuously arranged in the order mentioned and in the moving direction of the vanes. The increasing radius portion terminates in a first half of the whole circumferential length of the one cycle performing portion of the endless camming inner peripheral surface. The cam profile of the one cycle performing portion of the camming surface is calculated by the use of a single equation.

Abstract: In a multicylinder/double acting compressor, front and rear discharge chambers as well as front and rear suction chambers are out of communication with each other within the compressor. Arranged in one of the discharge chambers is a discharge valve formed of a rotary valve, which is disposed to close discharge ports communicating associated cylinder chambers with the same discharge chamber. The discharge valve is adapted to keep all the above discharge ports opened. An electromagnetic stop valve is connected between the above discharge chamber and an associated compression fluid circuit, for interrupting the communication therebetween.