| 摘要 |
<p>A new dockboard is provided of the kind having a ramp assembly mounted by frame means, the ramp assembly being constituted by a lip plate pivotally connected to the front edge of a main plate, which has its rear edge pivotally connected to the dockboard frame means. The ramp assembly is moved upward by springs, such upward movement being restrained under the control of an operator by a ratchet device. Means for elevating the lip plate relative to the main plate comprise an arm pivoted to the underside of the lip plate and controlled in its movement by guidance means mounted on the frame means. The arm carries one latch member which cooperates with another latch member movably mounted by the frame means, preferably by means of a pendulous support member.</p> |
