The option of equipping a dock leveler with Auto Return to Cross Traffic Position is only available on hydraulic dock levelers.
With the truck backed into position at the loading dock the overhead door and the trailer doors are opened, the dock attendant cycles the hydraulic dock leveler by depressing the up button on the wall mounted controls.
The dock leveler deck assembly raises and when the deck is fully raised the hydraulic operated lip extends. The dock attendant then releases the dock leveler up button and the deck assembly with the extended hydraulic lip lowers until the lip contacts the truck bed.
The truck is then loaded or unloaded and when completed the dock attendant typically re-activates the up button. The deck assembly raises and when the retracting hinged lip assembly clears the truck bed the up button is released and the dock leveler returns to the stored, closed position.
When the truck loading is completed and if there is no dock attendant available to return the dock leveler to the closed, stored position the truck driver departs the loading dock area. The dock leveler with the extended lip assembly now lowers to the below dock position and the lip slowly retracts. The dock leveler will remain in this below dock level position unless the dock leveler is equipped with optional Auto Return to Cross Traffic Position.
A hydraulic dock leveler equipped with auto return will eliminate the chance that the dock leveler remains in the below dock level position without a truck in position.
When the truck departs the deck assembly lowers and the extended lip slowly begins to retract. At a predetermined setting an actuator that is attached to the lip cylinder trips a limit switch which activates the lift motor and the deck assembly starts to rise and the lip completely retracts.
When the dock leveler deck assembly raises approximately 6” – 8” above finished floor level and the lip is fully retracted the limit switch de-activates, the lift motor shuts off and the deck lowers to the closed/stored position with the hinged lip parked behind the lower frame night locks.
The video link at the 5:43 minute mark shows the Auto Return to Cross Traffic Position option in operation. https://www.youtube.com/watch?v=eueQUqwEa_U
For additional information on any Pentalift product please contact the Pentalift Sales Department.