Overhead truck door opening and closing mechanism

A cargo truck comprising:

• an enclosed cargo hold with a door frame defined by parallel first and second vertical frame members and an upper cross frame member that is joined to the first and second vertical frame members to define two upper corners;
• the door frame defining a door opening for the cargo hold;
• a roll-up overhead door having a lower door portion;
• the roll-up overhead door being movable between open and closed positions with respect to the cargo hold of the truck;
• the closed position of the roll-up overhead door closing the door opening;
• an opening and closing mechanism for opening and closing the roll-up overhead door;
• the opening and closing mechanism having first and second guides aligned with the first vertical frame member;
• and a loop having portions passing over the first and second guides in a manner that allows the loop to be moved with respect to the guides;
• the positions of the first and second guides being fixed with respect to the door frame;
• the loop being disposed along the first vertical frame member outside of the cargo hold laterally spaced from the door opening when the roll-up overhead door is closed such that the loop is readily accessible for manipulation by a person opening the roll-up overhead door;
• the loop being connected to the lower door portion with a bracket;
• the bracket extending from the loop across a portion of the first vertical frame member to the door;
• and
• the loop being adapted to raise the roll-up overhead door from its closed position toward its open position and then lower the roll-up overhead door from its open position towards its closed position when pulled down toward the ground.