Pneumatic lock operator for roll-up doors for truck trailers

Abstract

A lock operator for operating locking rods in a roll-up door locking mechanism in a truck or trailer comprises a pneumatic drive cylinder for each locking rod that reciprocates the locking rod between its locked and unlocked positions. A button-operated actuator valve located at the front of the truck trailer connects the truck pressurized air system to all of the drive cylinders to lock the locking rods at all four comers of the trailer simultaneously. A spring or double acting cylinder return mechanism unlocks the locking mechanism when the air pressure is relieved. The pneumatic operators are mounted on mounting plates between the inside and outside skins of the trailer and are accessible through removable inspection plates on the inside of the trailer. Each drive cylinder is linked to a locking bar by a vertically reciprocable yoke mechanism.

Dependencies are inferred from the claim text.