Abstract: A power transmission coupling that includes a drive shaft hub selectively connectable to a driven shaft hub. The drive shaft hub includes a number of ball bearings disposed within bores in the drive shaft that are selectively engageable within a groove disposed on the driven hub. The bearings are selectively locked within the groove by a sleeve movable disposed around the drive hub over the bearings. The drive hub also includes a key secured thereto that is selectively received within notches or apertures formed in the driven hub to mechanically engage the drive hub with the driven hub for effective power transmission via the coupling.

Abstract: A roller system includes a frame, an upper roller assembly, a lower roller assembly and an actuator. In one embodiment, the upper roller assembly includes a first rotatably supported cylindrical member. The lower roller assembly is movably supported by the frame below the upper roller assembly and includes a second rotatably supported cylindrical member. The actuator is configured to move the second cylindrical member between an elevated position and a lowered position. In another embodiment, the roller system includes a frame, at least one upper track, an upper roller assembly, at least one lower track and a lower roller assembly. The upper roller assembly includes a first rotatably supported cylindrical member extending along an upper axis. The upper roller assembly is supported by the upper track and moves along the upper axis between an operation position and a removed position. The lower roller assembly includes a second rotatably supported cylindrical member extending along a lower axis.

Abstract: A roller system includes a frame, an upper roller assembly, a lower roller assembly and an actuator. In one embodiment, the upper roller assembly includes a first rotatably supported cylindrical member. The lower roller assembly is movably supported by the frame below the upper roller assembly and includes a second rotatably supported cylindrical member. The actuator is configured to move the second cylindrical member between an elevated position and a lowered position. In another embodiment, the roller system includes a frame, at least one upper track, an upper roller assembly, at least one lower track and a lower roller assembly. The upper roller assembly includes a first rotatably supported cylindrical member extending along an upper axis. The upper roller assembly is supported by the upper track and moves along the upper axis between an operation position and a removed position. The lower roller assembly includes a second rotatably supported cylindrical member extending along a lower axis.