Patent ID: 7089664
Filing Date: 2006-08-15
Classification: B21H,B21K,B23P,F01D,F02B,F05D,Y02T,Y10T

Abstract:
1. A method of manufacturing an adjustable blade for a VGS turbocharger, the adjustable blade including a shaft portion serving as a center of rotation and a blade portion for substantially adjusting the flow rate of exhaust gas, the adjustable blade being incorporated in the VGS turbocharger, wherein the exhaust gas discharged from an engine at a relatively low flow rate is suitably throttled to increase the velocity of the exhaust gas so that an exhaust turbine wheel is rotated by energy of the exhaust gas and a compressor directly coupled to the exhaust turbine wheel feeds more air into the engine than is fed into it by natural suction, and thereby a high output power of the engine is obtained at low rotational speeds: the method of manufacturing the adjustable blade comprising: a shaped material preparing step of forming a blank which is punched out from a metal material having a substantially constant thickness so as to have a volume capable of achieving the aimed at adjustable blade and which is a shaped material providing a starting form for the adjustable blade; a forming step of compressing the shaped material between a pair of opposed dies so as to form the blade portion, and the shaft portion; a trimming step of trimming a non-product portion of the shaped material protruding from a product portion that is formed in the forming step; a rolling step of pressing the shaft portion of the shaped material substantially including only the product portion against a pair of dies after finishing the trimming step so as to have a desired diametrical thickness; and a barreling step of surface polishing collectively the shaft portion, and the blade portion of the shaped material.