Abstract: An hydraulic drive supplies power to the rear wheels of a scraper at loading speeds providing a pushing assist to the tractor engine powering the tractor wheels at the front. The drive includes a piston type motor mounted on the stinger or pusher frame of the scraper and connected through a short torque shaft to a drive axle driving the scraper wheels. A signal generator senses ground speed to maintain the motor free-wheeling at speeds attainable by the tractor which would be destructive to the motor.

Abstract: An hydraulic control, especially for tractor scrapers, having a quick action capability employing a pilot fluid to unseat a holding valve initiating the release of high pressure exhaust fluid from a cylinder which is recirculated to the opposite end of the cylinder to obtain a regenerative effect providing a quicker action than the normal movement.

Abstract: An ejector roller and guide arrangement having a pair of rollers beveled on their outer edges, one on each side of the ejector frame, which travel between horizontal upper and lower tracks mounted on the pusher frame. The beveled edges of the rollers ride on inwardly angled surfaces of the track. Separate rollers on inwardly angled axes of rotation roll on separate track secured to the side walls of the bowl having outwardly angled surfaces. The longitudinally spaced rollers provide lateral and vertical guidance of the ejector in moving into and out of the scraper bowl for ejection of the earth material.