PURPOSE: To enhance mass-productivity by separately manufacturing a main shaft and a crank pin eccentrically arranged on an end of the main shaft and making them in a body by welding or screwing.
CONSTITUTION: A shaft 11 consists of a main shaft 11a and a crank pin 11b. A hole 13 is arranged in a circumferential position of a flange section 12 of the main shaft 11a with a required eccentricity relative to the axis of the main shaft 11a. An inserting portion 16 of the crank pin 11b is inserted to the hole 13. Pressing an electrode against a flange section 15, the main shaft 11a and the crank pin 11b are joined in a body by projection welding. As a result, mass- production can be performed with simple production equipment of highly general purpose.
AIKAWA HIDEKAZU
YAMAKIRI TSUNEO
