Caterpillar Inc.

Caterpillar Underground Mining Pty. Ltd.

Edward William Mate

Jeremy Todd Peterson

Beau Kuipers

Daniel Peter Sergison

William Norbert O'Neill

John James Krone

Thomas J Hajek

James Alvin Aardema

Steven Edward Johnson

Michael D Hudson

David Mork

Matthew Stephen Marquette

Bradly G Duffer

Jeffrey Kent Berry

Jeffrey Lee Kuehn

Dayao Chen

Douglas W Koehler

Srikrishnan T Tolappa

Richard A Carpenter

Riley A Albers

John R Connolly

Daryl Belshan

Patrick W Sullivan

Dennis Ray Barber

Jason P Wigg

Kalpeshkumar N Patel

Vincent Triffaux

John J Kaufman

Moses Imo Akpan

Eric P Jakubiak

Nathanael Garnet McRostie

James T Ferrier

Gene Richard St Germain

David R Evans

Glenn Stanfield

Scott D Vollmer

Dennis William Dicker

Fuaad Ahmed Sayeed

Andrew J De Haseth

Susan E Bieker

William F Erdman

A secondary steering pump system may include a secondary steering pump, a bypass valve having a first bypass position configured for placing the secondary steering pump in fluid communication with a hydraulic tank and a second use/testing position configured for placing the secondary steering pump in fluid communication with a steering control circuit. The system may also include a solenoid valve configured for actuation by a solenoid and for selectively actuating the bypass valve from the first position to the second position. The system may also include a pressure sensor configured for sensing pressure in the system.

Fault detection for secondary steering system

A machine includes a frame, a first steering arm, a second steering arm, a first hydraulic actuator coupled to the frame and the first steering arm, and a second hydraulic actuator coupled to the frame and the second steering arm. A first angle sensor measures a rotational displacement of the first hydraulic actuator relative to the first steering arm. A first link couples the first hydraulic actuator and the first sensor, and isolates movements other than the first rotational displacement. A second angle sensor measures a second rotational displacement of the second hydraulic actuator relative to the second steering arm. A second link couples the second hydraulic actuator and the second sensor, and isolates movements other than the second rotational displacement.

System for detecting failure of an Ackerman-type steering mechanism

A device for measuring rotation of a spherical joint in a steering system, may include an anchor secured within a ball stud of the spherical joint and a rotational tie having a first end and a second end. The first end of the rotational tie may be secured to the anchor to hold the first end parallel to a longitudinal axis of the ball stud. The device may also include a rotation sensor including a sensor target rotationally coupled to the second end of the rotational tie and secured for free rotation to a framework of the spherical joint. The rotation sensor may also include an angle sensor configured and arranged to sense a changing angle of the sensor target.

Direct sensing system for a spherical joint

A machine includes a first cylinder coupled to a first wheel and a second cylinder coupled to a second wheel. A first proportional dampening valve fluidly connects to the first cylinder and a second proportional dampening valve fluidly connects to the second cylinder. First accumulators are fluidly connected to the first cylinder and the first proportional dampening valve, and second accumulator(s) are fluidly connected to the second cylinder and the second proportional dampening valve. Additionally, a first proportional flow control valve fluidly connects to the first cylinder and a second proportional flow control valve fluidly connected to the second cylinder. An electronic control module (ECM) communicatively couples to the first proportional flow control valve and the second proportional flow control valve to adjust a ride height of the first wheel via the first cylinder and a ride height of the second wheel via the second cylinder.

Suspension system with individual ride height and dampening control

A machine includes a frame and an oscillating hitch. A first cylinder couples to a first side of the oscillating hitch and a first side of the frame. A second cylinder couples to a second side of the oscillating hitch and a second side of the frame. A first isolating mechanism couples to the first cylinder and rotates in response to a first rotation of the first cylinder relative to the frame or the oscillating hitch. A first angle sensor senses a first angular displacement of the first isolating mechanism about a first rotational axis. A second isolating mechanism couples to the second cylinder and rotates in response to a second rotation of the second cylinder relative to the frame or the oscillating hitch. A second angle sensor senses a second angular displacement of the second isolating mechanism about a second rotational axis.

System for detecting failure of an articulated steering mechanism

A redundant steering system comprises a primary power source; a secondary power source; first and second pumps operatively coupled to the primary and secondary power sources, respectively, to output first and second supplies of hydraulic fluid to a steering cylinder based on operation of the primary and secondary power source, respectively; first and second pairs of selector valves respectively coupled to the first and second pumps; and a charge circuit coupled to respective control inputs of the first and second pairs of selector valves to selectively supply hydraulic fluid to the control inputs of the first and second pairs of selector valves to stop hydraulic fluid from only one of the first pump and the second pump from being provided to the steering cylinder and to provide hydraulic fluid to the steering cylinder from only one of the other of the first pump and the second pump.

Redundant steering system and machines and methods thereof

A hydraulic system for controlling an implement on a work machine may include a hydraulic reservoir, a hydraulic pump in fluid communication with the reservoir, a central valve in fluid communication with the pump and configured for controlling the implement, a pressure relief system arranged in fluid communication with the hydraulic pump and the central valve, and a controller. The controller may be configured for controlling the hydraulic pump, the central valve and the pressure relief system and selecting between operating the hydraulic system at a first pressure and a second pressure based on a factor relating to implement position.

Variable system pressure based on implement position

A valve for controlling a hydraulic cylinder on a work machine may include a raising position configured for placing a pump in fluid communication with a cap end of the hydraulic cylinder. The valve may also include closed center position configured for closing off fluid communication to the cap end line and the rod end line. The valve may also include a lowering position configured for placing the pump in fluid communication with the rod end of the hydraulic cylinder. The valve may also include a snubbing position configured for placing the cap end in restricted flow fluid communication with the tank and for placing the rod end in restricted flow fluid communication with the tank.

Closed center hoist valve with snubbing

An autonomous steering control unit for a hydraulic steering control system has a pilot selector valve, primary and secondary electro-hydraulic (EH) steering valves, and an output selector valve. In a primary autonomous steering mode, the primary EH steering valve operates to output pilot fluid from the pilot selector valve through the output selector valve to the steering control system to control steering of a work machine while the pilot selector valve and the output selector valve isolate the secondary EH steering valve from the steering control system. In a secondary autonomous steering mode, the secondary EH steering valve operates to output pilot fluid through the output selector valve to the steering control system while the primary EH steering valve is isolated from the steering control system. In alternative embodiments, a load sense selector valve alternately connects an dynamic load sense line to the operative steering valve.

Hydraulic steering control system

A work machine includes an electric drive system. The work machine includes a prime mover, a machine controller, and a hydraulic control system. The hydraulic control system includes a pump, a control valve and a retarding control valve. The pump is configured to supply pressurized fluid to the hydraulic control system via a supply line. The control valve is fluidly coupled to the pump via the supply line, and includes a pressure relief valve. The retarding control valve is fluidly connected to the pump and the control valve. The retarding control valve includes a solenoid valve, an orifice and a check valve. The solenoid valve is coupled to the machine controller, the orifice restricts a flow of the pressurized fluid through the supply line, and the check valve is coupled to a discharge line, which branches from a point along the supply line between the solenoid valve and the orifice.

Hydraulic retarding control system

A hydraulic system is provided to selectively and independently route pressurized fluid to one or more operational systems of a machine. The hydraulic system is capable of switching fluid flow in operation from one of the operational systems to another of the operational systems in the event of hydraulic drive power being required by the latter one of the operational systems. The hydraulic system is also configured to continue supplying a nominal amount of fluid to support one or more auxiliary functions, for example, a lubrication system for bearings associated with the former one of the operational systems while routing the pressurized fluid to the latter one of the operational systems. A recirculation and anti-cavitation arrangement is also provided to allow recirculation of fluid to a hydraulic motor in the former one of the operational systems when pressurized fluid is being routed to the latter one of the operational systems.

System for selectively bypassing fluid supply to one or more operational systems of a machine

An emergency steering pump system for a primary pump providing a standby pressure via a primary output line includes a load sense line that is configured to branch-off from the primary output line. The load sense line has a first orifice disposed therein. A secondary pump is included for providing a margin pressure via a secondary output line that is coupled to the primary output line at a point downstream of the load sense line. A communication line is coupled to the primary output line at a point upstream of the load sense line. The communication line has a pressure control mechanism disposed therein. An output of the pressure control mechanism is coupled with an unloader valve of the secondary pump such that the pressure control mechanism is configured to bring about the margin pressure from the secondary pump.

Emergency steering pump system for a machine

A steering system for a machine is disclosed. The steering system may include a first pilot system including a first pilot source and a first set of electrohydraulic valves, and a second pilot system including a second pilot source and a second set of electrohydraulic valves. The first pilot system and the second pilot system may be configured to move the steering valve via pilot flow of the hydraulic fluid. The steering system may further include an electrohydraulic selector valve configured to regulate pilot flow to the first set of electrohydraulic valves and the second set of electrohydraulic valves. The electrohydraulic selector valve may be a two-position, five-way valve.

Electrohydraulic steering system with diagnostics

A hydraulic fan circuit is provided. The hydraulic fan circuit includes a tank, a motor having a fluid inlet and a fluid outlet and a pump to draw fluid at a low pressure from the tank and discharge the fluid at elevated pressures to the motor via the fluid inlet. The hydraulic fan circuit further includes a directional control valve disposed between the fluid outlet of the motor and the tank. The directional control valve is operable to move between a flow blocking position and a flow passing position. Further, the directional control valve is configured to reduce a positive speed of the motor below a lowest positive speed attainable through control of pump output. Furthermore, the hydraulic fan circuit includes a pressure control circuit configured to provide a pilot fluid flow at varying pressure to move the directional control valve.

Hydraulic system having low speed operation

A steering control system includes a steering circuit, a primary control circuit and a redundant control circuit. The primary control circuit includes primary proportional control valves, and a primary pilot valve having a thermal bleed of pilot fluid to warm the primary pilot valve when not operating to control the steering circuit. The redundant control circuit includes secondary proportional control valves, and a pressure reducing valve having a thermal bleed orifice allowing fluid flow to warm the pressure reducing valve when not operating to control the steering circuit. The thermal bleeds may also flow past the proportional control valves to raise their temperatures. The circuits of the steering control system are contained in a single valve group housing.

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Manhattan, IL, United States of America

Edward William Mate