| 摘要 |
<p>A cam, mounted on a shaft, has a series of stepped notches with each notch in line with a probe on a contact blade. The cam rotates in a cylindrical cavity which has crested internal teethed segments at the top and bottom. The cam has two diametrical bores which carries helical springs. Two cylindrical roller bearings are forced to the end of the cam surface parallel to its axis by the springs. The dia. of the bearings matches the pitch of the notched crests in such a way that the cam rotation progresses in discrete jumps as the bearings move over the rests. The cam mechanisms housed in a rectangular box. Insulation leads enter the box through grommets at a lower entry hole. The leads to to fixed supports for the contact blades in the upper portion of the box.</p> |
