| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce manufacturing cost of a housing and to improve durability by force-fitting a metallic bush into a center hole of the housing after the housing is manufactured by sintering a sintering member. SOLUTION: When a housing 10 is manufactured, a center hole 10a into which a cam shaft 6 is inserted is imparted to a sintering member at first. At the time, a metallic bush 21 is assembled with an inside surface of the housing 10. The sintering member with which the bush 21 is assembled is sintered and the housing 10 is completed. Because a sintered portion of the housing 10 does not come into contact with the cam shaft 6 and the metallic bush 21 comes into contact with the cam shaft 6, even if the cam shaft 6 revolves within the housing 10, uneven wear of the housing 10 can be prevented. As a result, manufacturing cost of the housing 10 can be reduced and a valve timing varying device having an effect of improving durability can be obtained.</p> |
