Abstract: An auxiliary speed control system for a vehical having an engine, a multiple ratio transmission and an operator's foot pedal for varying the engine speed. To obtain a vehicle speed which is different from any of those normally provided by the multiple ratio transmission, a device is moved into proximity to the operator's foot pedal. The device is contacted by the foot pedal when the foot pedal is depressed. When the speed of the vehicle reaches a predetermined maximum, the device acts on the foot pedal to prevent the operator from exceeding the selected speed.

Abstract: A screw type connection for rigidly mounting a piston on a rod and securing the connection. There is a pair of cooperating aligned slots in the outer piston and the inner rod. A locking member is located conjointly in the slots and a retainer member is provided to keep the locking member in position during operation.

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 outrigger for stabilizing a vehicle, including telescopic members and a power actuator to extend and retract the outrigger. The outer telescopic member is pivoted adjacent one side of the vehicle and extends beneath it. A combined guide and support member causes initial outward extension of the outrigger to be horizontal but toward the end of the horizontal travel the guide and support member causes outer end of the outrigger to move downwardly.

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 auxiliary speed control system for a vehicle having an engine, a multiple ratio transmission and an operator's foot pedal for varying the engine speed. To obtain a vehicle speed which is different from any of those normally provided by the multiple ratio transmission, a device is moved into proximity to the operator's foot pedal. The device is contacted by the foot pedal when the foot pedal is depressed. When the speed of the vehicle reaches a predetermined maximum, the device acts on the foot pedal to prevent the operator from exceeding the selected speed.

Abstract: A chain tensioning device, especially for scraper elevators, in which the distance between the head and foot shafts of the elevator is power adjusted to obtain the proper chain tension. A pressure source delivering a relatively constant supply of low pressure hydraulic fluid, such as the charging circuit of a hydrostatic elevator drive, is used to static load a cylinder against the desired catenary loading under idle conditions to retension the chains.