Abstract: Described is a system, device and method for coupling of a towing vehicle to a trailer or other towed item. A skid plate provides a surface on which a tongue of the towed item slides toward alignment over a hitch such as a hitch ball or pintle hook. The tongue, when approaching the correct location, impacts a latch. Movement of the latch facilitates movement of the skid plate downward, out of the way of the tongue. The skid plate automatically drops or tilts below the level of the hitch. The tongue of the trailer then drops onto, engages, or couples to the hitch.

Abstract: The throttle of an engine is controlled to maintain its speed substantially constant in spite of variations of load upon it. The illustrated load comprises hydraulically operated equipment in a hydraulic system powered by a pump driven by the engine. Throttle control mechanism comprises a pair of cylinders supplied from fluid pressure in the hydraulic system. Pistons in the respective cylinders are connected by pivots with a control arm linked to the throttle control. When equipment is hydraulically operated from the hydraulic system, the fluid back pressure against the pump increases, this back pressure being greater the greater the hydraulic load. The increased load on the engine from the pump would slow the engine down if its throttle opening were to remain at its original setting.

Abstract: A hydraulic motor maintains its speed substantially constant in spite of changes of hydraulic fluid pressure and flow. The motor comprises a rotor to which hydraulic fluid is delivered through a nozzle arrangement from an inlet port and exhausted from the rotor to an exit port. A by-pass duct interconnects the passageway for the incoming fluid with the passageway for the outgoing fluid, to by-pass the rotor. A spring-loaded piston is situated in relation to the entrance to the by-pass duct so that when the incoming fluid pressure is relatively high the piston is retracted to expose the by-pass duct to permit some of the hydraulic fluid to by-pass the rotor, and when the fluid pressure and flow rate decrease, the spring moves the piston to close up the entrance to the by-pass duct to reduce or even stop the flow through the by-pass. A manual diverter valve is situated to divert incoming fluid away from the rotor so that all the fluid is diverted directly out of the motor housing.

Abstract: The throttle of an engine is controlled to maintain its speed substantially constant in spite of variations of load upon it. The illustrated load comprises hydraulically operated equipment in a hydraulic system powered by a pump driven by the engine. Throttle control mechanism comprises a pair of cylinders supplied from fluid pressure in the hydraulic system. Pistons in the respective cylinders are connected by pivots with a control arm linked to the throttle control. When equipment is hydraulically operated from the hydraulic system, the fluid back pressure against the pump increases, this back pressure being greater the greater the hydraulic load. The increased load on the engine from the pump would slow the engine down if its throttle opening were to remain at its original setting.

Abstract: An extendible and contractible shaft comprises a number of shaft members on a common longitudinal axis, each except the outermost member being telescoped within the one next adjacent. Each telescoped member has a piston slidably sealed to the inner wall of the next adjacent outer member to form a series of tandem arranged sealed pistons. Fluid passageways are provided between adjacent shaft members so that fluid supplied under pressure to an inlet port of the device flows through the passageways to all the piston heads, thereby extending the telescoped shaft members and at the same time driving fluid out from under each piston through fluid passageways to an exit port of the device. When the pressurized fluid flow is reversed to send pressurized fluid to the undersides of the pistons, thereby driving fluid above the piston heads out through the first mentioned port, there would normally be incurred substantial shock as each piston head strikes its stop in the retraction operation.

Abstract: A uniquely integrated arrangement of concentric tubes in combination with concentric pistons and special interconnecting fluid pressure passages therein, said component members cooperating in a manner as to permit extreme compound extension or retraction, while special cross-section configuration allows efficient transmission of axial torque energy without slippage between collinear members, so that when driven as a Kelly drive for earth drilling the torque is transmitted to a drilling auger.