Abstract: A loading dock includes a dock leveler movable between raised and lowered positions. The dock leveler includes a dock board and a lip assembly that can be horizontally extended and retracted relative to the forward edge of the dock board. The ability of the lip to extend and retract horizontally means that the dock board does not have to be raised as far to extend the lip as in prior dock levelers having a pivotally mounted lip. This eliminates or reduces the need for toe protection structure at the sides of the dock board and enhances manufacturing economy without compromising safety.

Abstract: A dock leveler for providing a bridge into the rear end of a truck trailer over which a fork vehicle can travel in loading the truck trailer. The dock leveler includes a ramp with a rear section and an extendible forward section. The forward section telescopically extends from and retracts into the rear section under power from a hydraulic cylinder. The forward section can be locked in place to prevent retraction of said forward section relative to said rear section under the traction developed by the drive wheels of a fork vehicle as the fork vehicle travels over the dock leveler. Various structures for indicating the amount of overlap of the dock leveler on the truck trailer are also provided.

Abstract: A dock leveler is mounted in a pit formed in the floor of the loading dock area of a factory, warehouse or similar facility. The loading dock includes an overhead door adjacent the dock leveler. The dock leveler is retractable so that, when it is not in use, it can be stored fully within the facility inboard of the overhead door. To prevent vehicles from inadvertently falling off the end of the stored dock leveler, the dock leveler includes a raisable barrier. When raised, the barrier is located between the end of the dock leveler and the overhead door. In addition to preventing vehicles from accidentally running off the end of the dock leveler, the barrier also protects the overhead door from accidental collisions with such vehicles. When the dock leveler is in use, the barrier folds away to a position below the extendible ramp. Alternatively, the dock leveler can be non-retractable and the barrier can be raised and lowered in from of the ramp.

Abstract: A hydraulic system (40) for an excavator (10) which utilizes regeneration, minimizes cavitation, and provides hose break protection is disclosed. A valve assembly (50) is permanently connected to a hydraulic actuator (30) which is to be controlled. A hydraulic power supply (42) remote from the hydraulic actuator is connected to the valve assembly (50) through a pair of flexible hoses (56, 58). Pressurized hydraulic fluid can flow to the valve assembly through either of the flexible hydraulic hoses, but the valve assembly (50) includes a check valve (60) so hydraulic fluid return is only possible through one hose (56). A two position valve (62) is provided in the valve assembly (50) between a pair of operating ports (36, 38) on the hydraulic actuator (30). The two position valve (62) can be opened in response to a signal from the operator, connecting the two ports (36, 38) together to permit regeneration.