Vane compressor

A vane compressor comprising:

• a compressing element that compresses a refrigerant, the compressing element including
• a cylinder having a cylindrical inner circumferential surface;
• a rotor shaft including a cylindrical rotor portion and a rotating shaft portion in the cylinder, the rotor portion being configured to rotate about an axis of rotation offset from a central axis of the inner circumferential surface by a predetermined distance, the rotating shaft portion being configured to transmit a rotational force from an outside to the rotor portion;
• a frame that closes one of openings defined by the inner circumferential surface of the cylinder and supports the rotating shaft portion by a main bearing portion thereof;
• a cylinder head that closes the other of the openings defined by the inner circumferential surface of the cylinder and supports the rotating shaft portion by a main bearing portion thereof;
• and
• at least one vane provided to the rotor portion and whose tip projects from the rotor portion and is shaped as an arc that is convex outward,
• wherein the vane compressor further comprises
• a vane supporting unit that supports the vane such that the refrigerant is compressed in a space defined by the vane, an outer circumference of the rotor portion, and the inner circumferential surface of the cylinder and such that a line normal to the arc at the tip of the vane and a line normal to the inner circumferential surface of the cylinder always substantially coincide with each other, the vane supporting unit supporting the vane such that the vane is rotatable, and movable in a substantially centrifugal direction with respect to the rotor portion, the vane supporting unit holding the vane such that a predetermined gap is provided between the tip of the vane and the inner circumferential surface of the cylinder in a state where the tip has moved by a maximum length toward the inner circumferential surface of the cylinder,
• wherein the vane supporting unit includes
• a bush holding portion provided closely to the outer circumference of the rotor portion and extending through the vane supporting unit in a direction of a central axis of the rotor portion, the bush holding portion having a substantially circular cross-section that is taken perpendicularly to the central axis;
• a bush including a pair of members each having a substantially semicircular columnar shape, the members being fitted in the bush holding portion and holding the vane therebetween in the bush holding portion;
• and
• a first vane relief portion extending through the rotor portion in the direction of the central axis of the rotor portion such that an end facet of the vane that is close to an inner circumferential surface center is kept out of contact with the rotor portion,
• wherein the vane includes a pair of vane aligner portions each shaped as a part of a ring, one of the vane aligner portions being provided closely to a part of an end facet of the vane that is on a side close to the frame and that is close to the center of the rotor portion, the other vane aligner portion being provided closely to a part of an end facet of the vane that is on a side close to the cylinder head and that is close to the center of the rotor portion,
• wherein the frame and the cylinder head each have a recess or a groove provided in an end facet thereof that is close to the cylinder, the recess or the groove being concentric with respect to the inner circumferential surface of the cylinder, and
• wherein the vane aligner portions are fitted in the recess or the groove and are supported by a vane aligner bearing portion provided as an outer circumferential surface of the recess or the groove,
• wherein the rotor shaft is an integral body including the rotor portion and the rotating shaft portion, and
• wherein the end facet of the vane that is close to the inner circumferential surface center, which is the center of the inner circumferential surface of the cylinder, is always positioned on an inner side of the rotor portion than a center of rotation of the vane that is rotatable with respect to the rotor portion.