Abstract: A steering system for a work vehicle having a steerable wheel. The steering system includes a steering input device configured to provide a first steering input and a second steering input to move the steerable wheel. A pilot system is operatively connected to the steering input device and includes a first pilot line operatively connected to the first steering input and a second pilot line operatively connected to the second steering input. A piloted system is operatively connected to the pilot system and includes a direction control valve operatively connected to each of the first and second pilot lines and to a steering cylinder. The steering cylinder is coupled to the steerable wheel. The direction control valve responds to each of the pressure signals of the first and second pilot lines to adjust the position of the steering cylinder which in turn moves the steerable wheel.

Abstract: A steering system for a work vehicle having a steerable wheel. The steering system includes a steering input device configured to provide a first steering input and a second steering input to move the steerable wheel. A pilot system is operatively connected to the steering input device and includes a first pilot line operatively connected to the first steering input and a second pilot line operatively connected to the second steering input. A piloted system is operatively connected to the pilot system and includes a direction control valve operatively connected to each of the first and second pilot lines and to a steering cylinder. The steering cylinder is coupled to the steerable wheel. The direction control valve responds to each of the pressure signals of the first and second pilot lines to adjust the position of the steering cylinder which in turn moves the steerable wheel.

Abstract: A steering system for a work vehicle having a steerable wheel. The steering system includes a steering input device configured to provide a first steering input and a second steering input to move the steerable wheel. A pilot system is operatively connected to the steering input device and includes a first pilot line operatively connected to the first steering input and a second pilot line operatively connected to the second steering input. A piloted system is operatively connected to the pilot system and includes a direction control valve operatively connected to each of the first and second pilot lines and to a steering cylinder. The steering cylinder is coupled to the steerable wheel. The direction control valve responds to each of the pressure signals of the first and second pilot lines to adjust the position of the steering cylinder which in turn moves the steerable wheel.

Abstract: A steering system for a work vehicle having a steerable wheel. The steering system includes a steering input device configured to provide a first steering input and a second steering input to move the steerable wheel. A pilot system is operatively connected to the steering input device and includes a first pilot line operatively connected to the first steering input and a second pilot line operatively connected to the second steering input. A piloted system is operatively connected to the pilot system and includes a direction control valve operatively connected to each of the first and second pilot lines and to a steering cylinder. The steering cylinder is coupled to the steerable wheel. The direction control valve responds to each of the pressure signals of the first and second pilot lines to adjust the position of the steering cylinder which in turn moves the steerable wheel.

Abstract: A valve control unit is connected to a control valve and automatically moves a valve spool first and second bleed positions. The control unit prevents valve bleed if the control valve is in its extend or retract position under command of the operator. The control unit prevents a valve bleed if a temperature of oil in the reservoir is not less than a reference temperature. The control unit prevents a valve bleed if a speed of the vehicle is less than a reference speed. The control unit automatically returns the spool to its neutral position from the first and second bleed positions.

Abstract: Left and right two stage brake valves communicate fluid pressure to left and right brake mechanisms, each brake valve having an inlet for receiving pressurized brake fluid, a reservoir, a stepped bore and a stepped piston. The stepped bore and the stepped piston forming a high volume prefill chamber and a high pressure chamber. A prefill drain valve communicates the prefill chambers to the reservoir only when pump pressure is available at the inlet and blocks communication between the left and right prefill chambers and between the prefill chambers and a reservoir when pump pressure is not available at the inlet.

Abstract: A hydraulic system includes a hydraulic pump which provides pressurized fluid at an output port as a function of pressure in a load sensing port, a hydraulic reservoir, and a load pressure sensing line connected to the load sensing port. A solenoid operated implement control valve controls fluid communication to and from a hydraulic function such as a cylinder. A supply control valve has a first position wherein the reservoir is communicated with the load sensing port and a second position wherein the pump output port is communicated with the load sensing port. A spring urges the valve member to its first position, and a solenoid is energizable to move the valve member to its second position. The solenoid is energized when the implement control valve is activated so that the supply control valve communicates pump pressure to the load sensing port and the pump will operate at full capacity whenever the second hydraulic function is operated.

Abstract: A charge flow distribution valve routes all charge pump flow into a main pump until the main pump has sufficient inlet pressure. The valve opens to a first stage which routes excess charge flow to lubrication circuits. At a slightly higher main pump inlet pressure, it also routes oil to an inlet of the charge pump.

Abstract: A closed center, load sensing hydraulic system is disclosed which contains a primary work circuit which has priority in flow demand over a secondary work circuit. The system includes a variable displacement pump fluidly connected between a reservoir and a control valve with the primary work circuit. The primary work circuit includes a control valve which regulates fluid flow from the pump to a primary hydraulic function and which includes a feedback mechanism connected thereto. The secondary work circuit also includes a manually operable control valve for regulating fluid flow from the pump to a secondary hydraulic function. A priority valve is connected between the pump and the secondary work circuit and movable between an open and a closed position to regulate the pressure of fluid discharged by the pump.

Abstract: An open center, load sensing hydraulic system is disclosed which contains a primary work circuit and a secondary work circuit. A fixed displacement pump is fluidly connected between a reservoir and both the primary and secondary work circuits for supplying pressurized fluid thereto. The primary work circuit includes a control valve which regulates fluid flow from the pump to a primary hydraulic function and which includes a feedback mechanism connected thereto. The secondary work circuit includes a manually operable control valve for regulating fluid flow from the pump to a secondary hydraulic function. A priority valve is connected between the pump and both the primary and secondary work circuits and is movable to regulate the pressure to the primary work circuit.

Abstract: An open center hydraulic system is disclosed which contains a primary work circuit and a secondary work circuit. A fixed displacement pump is fluidly connected between a reservoir and the primary and secondary work circuits for supplying pressurized fluid thereto. The primary work circuit includes a control valve which regulates fluid flow from the pump to a primary hydraulic function and which includes a feedback mechanism connected thereto. The secondary work circuit also includes a manually operable control valve for regulating fluid flow from the pump to a secondary hydraulic function. A priority valve is connected between the pump and the secondary work circuit and is movable between an open and a closed position to regulate the pressure of fluid discharged by the pump.

Abstract: A load sensing hydraulic system is disclosed which essentially eliminates kickback from a feedback mechanism contained in a manually operable control valve which in turn is fluidly connected to a hydraulic function. The system includes a power on demand pump fluidly connected between a reservoir and the control valve for supplying pressurized fluid to the hydraulic function. A load signal line is also connected between the control valve and the pump which serves to transmit pressure signals, which are generated by loads acting on the hydraulic function, to the pump for controlling the pressurized output thereof. A load signal control valve is positioned in the load signal line and is fluidly connected to the discharge side of the pump. The load signal control valve is capable of sensing pressure variations between the fluid discharged by the pump and the upstream fluid present in the load signal line.

Abstract: An in-line filter element is disposed within a tubular valve spool which shifts to either meter or shut-off fluid flow through the valve in response to a preselected pressure differential across the valve and element which is some value below a value which could result in damage to the filter element.