FLOW RATE-VARIABLE VALVE MECHANISM AND VEHICLE SUPERCHARGER

摘要

A wastegate valve (37) is provided with a coil spring (67) capable of extending and contracting in the axial direction of a valve shaft (63) of a valve (57) between a washer (65) and an attachment tongue (53) in the axial direction of the valve shaft (63), the coil spring (67) is configured of a heat-resistant alloy or ceramic, and an annular guard wall (69) is formed on the surface of the attachment tongue (53) by counter boring so as to enclose the coil spring (67).