| 摘要 |
The present vehicle speed bump device allows a vehicle to roll over the device slowly with little resistance. However, the device includes a lock which operates to lock the speed bump of the device in operative position when contacted by a vehicle wheel moving at a higher speed, thereby causing an appreciable bump effect. The device includes a frame having a transverse bump bar at its upper end and a counterweight bar at its lower end. The frame is rotatably mounted by transverse axles secured to opposite sides of an open-topped container. In the resting position, the bump bar projects up above the open top. A lock arm projects rearwardly from and is rigidly interconnected to the frame for rotation therewith. It bears a vertical pendulum arm which rotates forwardly and rearwardly and which has a friction block at its lower end. A second friction block is mounted in the container below and to the rear of the first friction block. The two blocks contact and lock together to prevent continued rotation of the frame only when the bump bar is struck with sufficient force by a fast traveling vehicle wheel to swing the first friction block into the second block as the frame rotates. As a result the bump bar remains up above the container to transmit a large bump to the vehicle, the frame being locked in place.
|
