Abstract: A typical fluid mixer of the heavy-duty type conventionally has a compartment including walls, one of which has a circular opening through which a motor-driven shaft extends. An external seal is provided for sealing the shaft-to-wall junction against fluid leakage. When it becomes necessary to replace the seal, the compartment must be drained to avoid leakage at the opening. The present invention provides an internal seal that is normally spaced along the shaft away from the wall but which can be forcibly moved toward and compressed against the wall and thus seal the shaft and opening and preventing leakage during repairs and consequently eliminating emptying the tank. The interior seal is supported by a movable carrier, and reversible force-exerting mechanism extending exteriorly of the compartment is employed to move the carrier and interior seal into and out of its interior sealing position. In a preferred embodiment, the force-exerting mechanism includes one or more jack screws.

Abstract: A rotary tool, adapted to be chucked in a rotary power tool, is provided with cutting blades for cutting away the annulus that surrounds the core portion of a lock of the type referred to above. When the annulus is cut away, the tumbler mechanism is exposed axially outwardly so that the tumblers may be actuated by a depressor tool for opening the lock in the event the key has been lost. The cutter has an axial tubular front end portion that pilots on the lock core and fits the annular gap between the core and surrounding portion of the lock. The front end of the cutter has a stop portion projecting axially ahead of the front cutting edges to limit the depth of the cut and to prevent damage to the projecting ends of the tumbler pins.

Abstract: A climbing device for climbing columns such as girders having flanges. The devices are worn in pairs on the feet of the climber and each is equipped with a gripping member having spaced apart jaws adapted to grip the column flange. The gripping member on each device is mounted on the foot-attached or base member for selective swinging between two positions, one a climbing position in which each pair of jaws extends laterally inwardly of the respective foot and the other a retracted position in which the jaws extend laterally outwardly and behind the heel of the climber's foot so as to be out of the way when not used for climbing. Means is provided for selectively locking the gripping member to the base member in either of said positions.