Patent ID: 8689552

Claim:
A centrifugal compressor comprising: a housing which houses a compressor wheel therein and supports the compressor wheel so as to be rotatable about an axis; a spiral scroll which is provided in the housing so as to be arranged in an outer periphery of the compressor wheel; and a diffuser portion which is provided as a path space communicating with the scroll from an outlet side of the compressor wheel and is formed by a pair of wall portions facing each other, wherein the centrifugal compressor further comprises: a movable vane which is movable between a projecting position where the movable vane projects so as to cross the diffuser portion from a first wall portion of the pair of wall portions and a housing position where the movable vane retracts toward the first wall portion from the projecting position so as to be housed in a housing portion provided in the first wall portion; and a driving device which drives the movable vane between the projecting position and the housing position, wherein the driving device includes an operation chamber which is provided in wall a second wall portion of the pair of wall portions, a partition member which is movable inside the operation chamber in a reciprocating manner so as to divide the inside of the operation chamber into a first chamber provided on a diffuser portion side and a second chamber provided on an anti-diffuser portion side opposite side of the diffuser portion side, a connection member which connects the partition member and the movable vane to each other so as to be operated as one unit through a penetration hole provided in the second wall portion, a spring device which presses at least either one of the movable vane and the partition member toward either a first side of the diffuser portion side or the anti-diffuser portion side so that the partition member moves toward the first side, and a pressure control device which is capable of controlling a difference between a pressure of the first chamber and a pressure of the second chamber so that the partition member moves toward the other side of the diffuser portion side or the anti-diffuser portion side against the spring device, wherein the movable vane is provided with a shaft member which extends from the movable vane toward the first wall portion so as to be parallel to a movement direction of the movable vane, the one wall first wall portion is provided with a support hole which supports the shaft member in a slidable manner, and the movable vane is supported at both sides thereof by the pair of wall portions respectively due to the connection member supported by the second wall portion and the shaft member supported by the first wall portion.