| 摘要 |
The invention concerns apparatus for opening and closing gates comprising a drive means driven by an electric motor (8) and which is connected to a crank (19) on the gate wings (1, 2) by longitudinally resilient connecting links (18) which absorb the movement of the drive means in the event that either of the gate wings strikes an obstacle. The drive means is preferably a rotatably heart-shaped cam (13) which moves a cam follower (15) connected to the connecting links. The invention also provides actuator means (30), which may comprise spring-loaded pads or a hydraulic tube, which are operable by a vehicle approaching the gates to set the drive means in motion. The gates are kept in the closed position by a latch (80) which is automatically released when the drive means is set in motion. <IMAGE> |
