| 摘要 |
The servo drive mechanism, eg. for an up and over door (2) has a flexible drive element (3) inside a fixed support rail (1). A traveller (13) attached to the drive element is linked to the door by a double armed drive lever (17,18) with a ratchet profile on one lever, at the joint. This catch engages a ratchet slot in the support rail in the closed position and locks the door mechanism. The ratchet catch is lifted by the opening movement of the door mechanism, which is powered by an electric servo motor. A simple ratchet tag formed into the end of one of the levers provides a secure grip with the rail. |
