| 摘要 |
A drive mechanism for actuating a movable element comprising an actuating means configured to drive a movable element between a first position and a second position, and any position there between, when driven by a rotatable drive means whereby the rotatable drive means is configured not to have any driving effect on the actuating means thereby driving the movable element beyond the first position or second position. The drive means is configured to be continuously rotatable in a first direction such that, as it is rotated in a first direction, the drive means drives the actuating means until the movable element reaches the first position and then the drive means slips relative to the actuating means when the movable element is in the first position; and the drive means is configured to be continuously rotatable in a second direction such that, as it is rotated in the second direction, the drives means drives the actuating means until the movable element reaches the second position and then the drive means slips relative to the actuating means when the movable element is in the second position. |
