Abstract: An overhead door assembly is disclosed having a pair of rails each with upright and horizontal segments. Pivot supports at the lower ends of the upright segments permit the rails and a door thereon to move into and out of the doorway of a temperature controlled storage structure. A control shaft imparts movement to the rails by arm assemblies each including pivotally coupled arms to tilt the rail segments and door thereon between open and closed positions. The door is held in a closed position by an over-center relationship in each arm assembly. The control shaft is manually actuated while modified rail positioning arrangement includes a pneumatic cylinder and a valve control for rail positioning. Seals about the door and between panels of the door render the storage structure airtight.

Abstract: A T-shaped seal is disclosed for installation in the gap between a scale pit wall and a scale platform to prevent entry of foreign matter into the area below the platform. An upright stem of the seal is provided on its sides with vertically spaced ribs which may flex during installation between the scale pit wall and the platform edge. The ribs prevent upward dislodgement of the seal against all but intentional efforts and provide additional barriers to foreign material. The stem is of a flexible nature to accomodate irregular pit wall and scale surfaces. A ventilator is shown for installation within an opening formed in the flange portion of the seal and serves to permit the circulation of air beneath the platform while preventing the entry of material into the gap between the scale platform and pit wall.