摘要 |
A mechanical automatic clearance adjuster, such as may be used as a valve clearance adjuster in an internal combustion engine, comprises a self-contained mechanism having an internally screw threaded housing (26) within which there is a complementarily threaded screw member (28). The screw threads exhibit a relatively high friction in one direction of axial loading thereof compared with a relatively low friction in the opposite direction of axial loading whereby the screw member (28) may rotate and advance axially of the housing (26) solely under the action of a compression spring (34) acting between the screw member (28) and an end cap (30). |