SHAFT

PROBLEM TO BE SOLVED: To efficiently produce a shaft with a connection part of either one of a first shaft and a second shaft having a DLC (Diamond Like Carbon) coating. SOLUTION: Mounting grooves 34 are provided on the outer peripheral face of the connection part 32 of the second shaft 30 and torque transmission members 36 are press-fitted and integrally fixed in the mounting grooves 34 so that portions protruding from the mounting grooves 34 function as spline teeth and are meshed with spline grooves 16 of the first shaft 12 and torque is transmitted between the first shaft 12 and the second shaft 30 via the torque transmission members 36. In that case, the torque transmission members 36 are applied with the DLC coating for the purpose of countermeasure against noise, improvement of wear resistance, etc. Since the torque transmission members 36 are small as compared with the first shaft 12 and the second shaft 30, many torque transmission members 36 can be placed in a DLC furnace at the same time and be subjected to coating treatment efficiently, so that the productivity is improved and the manufacturing cost is reduced. COPYRIGHT: (C)2011,JPO&INPIT