Abstract: Motorized door assemblies having a door pivoting about a pivot axis extending across opposing jambs. In one aspect, the assembly includes a motor assembly having a motor, drive gears, slip clutch, and driven shaft connected to the door to pivot it about the pivot axis. The slip clutch includes a clutch plate slideable along the driven shaft, a drive plate driven by the motor via the drive gears, and a clutch spring urging the clutch plate into engagement with the drive plate, where the clutch and drive plates have profiled and counter-profiled faces. In another aspect, a break beam emitter and receiver are mounted to respective ones of the opposing jambs along a beam axis extending parallel to the pivot axis and proximate to an edge of the door opposite the pivot axis. Interruption of a light beam projected therebetween alters operation of a motor assembly.

Abstract: A soil compactor having three compacting rollers supported from a frame with each of the rollers being independently powered by a hydraulic motor with the controls for the hydraulic motors being located at the rear of the compactor so that an operator walking behind the compactor will be able to control movement of the compactor. A vibration device is supported from a frame in generally a central position between the single front roller and the pair of rear rollers. The vibration device is an eccentric weight on a shaft driven at high speeds by a hydraulic motor with the central location of the vibration device producing a vibrating effect to aid in compaction and also aiding in maneuverability by providing a "floating" effect.