PURPOSE: To improve control responsiveness of a valve timing by further improving movement responsiveness of a cylindrical gear which is moved axially through a piston.
CONSTITUTION: In a cylindrical gear 8, a sproket 1 is meshed with a sleeve 4 through a helical internal/external teeth. The cylindrical gear 8 is moved by relative pressure between hydraulic pressure in a pressure receiving chamber 14 and spring force of a return spring 23, through a piston 13, so that relative rotational phase of the sproket 1 and a cam shaft 2 is converted. A clearance is formed between a support pin 16 fixed to the piston 13 and a pin hole 10c of a rear gear structural part 10 to which a shaft 16b of the support pin 16 is slid, for eliminating dislocation of axes of the support pin 16 and the pin hole 10c.
IMAI HIROAKI
UCHIDA KATSUHIKO
