| 摘要 |
<p>An automatic valve clearance adjuster comprising an internally screw-threaded housing (1); an externally screw-threaded screw member (3) extending within the housing; the screw thread (4) of the screw member (3) having an external form which is complementary to the thread form of the internal thread (2) of the housing and fits therein with a predetermined axial clearance, the thread being trapezoidal in form, symmetrical in axial cross-section and exhibiting equal frictional resistance against movement in both axial directions; wherein the flank angles, helix angle and number of starts of the screw thread are selected to ensure that the screw member will rotate and advance axially out of the housing solely under the influence of an axial force on its end within the housing; and the emerging end (7) of the screw member is adapted to work in conjunction with an adjacent component to receive therefrom a frictional resistance to rotation.</p> |
