| 摘要 |
A hold-down device for a mechanical dock leveler which is spring loaded so that when the hold-down device is released the deck will rise and the lip will extend. When the deck is walked down, the hold-down device maintains the deck in contact with the truck bed. This is accomplished by means of the interaction and geometry between a brake actuating arm and a brake release arm and the associated pins. As the dock leveler is lowered, the perpendicular distance from an anchor pin to the center line of a slot in the brake actuating arm increases. This causes the brake actuating arm to move upward increasing tension on the brake band. The brake release arm moves and increases the braking force. As the dock leveler is raised the braking force is reduced. The leveler includes a two-stage safety leg with a guide bar attached to the safety leg stop. The guide bar limits free travel of the safety leg. The guide bar engages projecting tabs from each stage of the safety leg to require upward or free movement above a respective engagement position before the safety leg can move forward and re-engage the stop. |
