Caterpillar Inc.

Shin Caterpillar Mitsubishi Ltd.

Other

David P Smith

Daniel T Mather

Rudy Van Mills

Thomas J Hajek

Chad Timothy Brickner

William Christopher Swick

Jonathan L Buelow

Eric R Lauterbach

Igor Strashny

Paul Anthony Dvorak

Michael Johnston

James Alvin Aardema

William K Engel

Ronnie L Satzler

Stephen W Rector

Steven T Ufheil

Richard J Skiba

John R Connolly

Dennis J Hausman

Wayne W Lark

Randall A Harlow

Peter R Hildner

Robert A Aarestad

Steven L Groth

David J Carlson

Phillip J Wenger

Howard Savage

Guy C Carlson, Jr

Richard A Arstein

Paul Gilbert

Mark R Coppley

A hydraulic energy recovery device for a hydraulic system is disclosed. The hydraulic energy recovery device has a first impeller configured to receive a flow of pressurized liquid, and a second impeller configured to pressurize a flow of liquid. The hydraulic energy recovery device also has a common shaft connecting the first and second impellers.

Hydraulic system having in-sump energy recovery device

A sprag is disclosed. The sprag is configured to operate in a first mode allowing substantially mutual rotation of inner and outer races about an axis and a second mode allowing relative rotation between the inner and outer races. The sprag includes at least one actuator configured to selectively extend and retract and an outer surface configured to selectively lock the inner and outer races together as a function of the at least one actuator selectively extending.

Fluidly actuated sprag

A fluid motor including an inner race and an outer race is disclosed. The inner and outer races are configured to rotate about a substantially common axis. The motor also includes at least one fluid actuator configured to produce substantially linear motion as a function of selectively receiving pressurized fluid. The fluid motor also includes at least one sprag configured to rotate the inner and outer races about the axis as a function of the substantially linear motion.

Fluid motor

A hydraulic system for a work machine is provided. The hydraulic regeneration system has a tank, a primary source, a first actuator, an accumulator, and a first valve mechanism. The tank is configured to hold a supply of fluid. The primary source is configured to pressurize the fluid and has a suction inlet and a discharge outlet. The first actuator is configured to receive pressurized fluid from the discharge outlet of the primary source. The accumulator is in fluid communication with the tank, the suction inlet of the primary source, and the first actuator. The first valve mechanism is disposed between the suction inlet of the primary source and the accumulator, and is movable between a first position at which fluid returning from the first actuator is directed to the suction inlet of the primary source, and a second position at which fluid returning from the first actuator is directed to only the accumulator.

Hydraulic regeneration system

A poppet valve arrangement is provided and has a poppet slideably disposed therein. The poppet has an odd number of integral guide legs formed thereon about the periphery of the poppet. The odd number of integral guide legs are evenly spaced from one another and are of a size sufficient to permit fluid to freely flow thereby when unseated. The integral guide legs also function to permit the poppet to freely slide, without binding, within a bore of the poppet valve arrangement. The poppet having integral guide legs is compact, versatile, cost effective to produce and has good strength.

Poppet valve arrangements

A metering valve for a work machine hydraulic system is disclosed. The metering valve has an inlet and an outlet, a main poppet, and a solenoid-operated pilot element. The main poppet is movable to pass fluid from the inlet to the outlet, and to block fluid from the inlet to the outlet. The solenoid-operated pilot element is movable between a first position at which pressurized fluid from the inlet pressurizes a control chamber in communication with a control end of the main poppet to urge the main poppet toward the flow-blocking position, and a second position at which the control chamber is communicated with a drain to move the main poppet toward the flow-passing position. The metering valve also has a relief valve element configured to drain pressurized fluid from the control chamber to move the main poppet toward the flow-passing position in response to a pressure at the inlet exceeding a predetermined pressure.

Metering valve with integral relief and makeup function

A metering valve for a work machine hydraulic system is disclosed. The metering valve has a valve body with an inlet and an outlet. The metering valve also has a main poppet disposed within the valve body between the inlet and the outlet. The main poppet has a nose end and a chamber end, and is movable between a flow-passing position at which fluid flows from the inlet to the outlet, and a flow-blocking position at which fluid flow between the inlet and outlet is blocked. The metering valve also has a pilot element movable to selectively communicate the chamber end of the main poppet with a drain, thereby affecting movement of the main poppet between the flow-passing and flow-blocking positions. The metering valve further has a solenoid mechanism operable to move the pilot element. The position of the pilot element is affected by a fluid pressure at the inlet.

Electro-hydraulic metering valve with integral flow control

A system and method for starting an engine having a crankshaft is provided. Pressurized fluid is stored in an accumulator. A flow of pressurized fluid is released from the accumulator. The flow of pressurized fluid released from the accumulator is directed to a pump that is operatively engaged with the crankshaft of the engine. The flow of pressurized fluid drives the pump to generate a rotation of the crankshaft and thereby start the engine.

System and method for starting an engine

An electro-hydraulic valve is provided for use in a system to control flow and/or pressure within the system. An electro-hydraulic valve arrangement includes a housing and a valving mechanism disposed in the housing. The electro-hydraulic valve arrangement has a hold coil assembly connected to the housing adjacent to the valving mechanism. A force control member having a clapper face is positioned adjacent to the hold coil assembly and the clapper face thereof is maintained at a predetermined distance from a coil face of the hold coil assembly. A double precision adjustment mechanism is operative associated with the force control member and is operative to precisely control the distance between the coil face and the clapper face.

Electro-hydraulic valve and system

A fluid control system includes a pressure supply and a valve arrangement having an inlet and an outlet and being in fluid communication with the pressure supply. The valve arrangement includes a relief operator configured to provide fluid communication between the inlet and the outlet of the valve arrangement in response to a predetermined pressure condition at said inlet. The valve arrangement is configured to provide fluid communication between the inlet and the outlet of the valve arrangement in response to an outlet pressure being greater than an inlet pressure.

Fluid system having variable pressure relief

A hydraulic regeneration system for a work machine is provided. The hydraulic regeneration system includes a first hydraulic actuator having a first chamber and a second chamber, a second hydraulic actuator having a third chamber and a fourth chamber, and a source of pressurized fluid. A first directional control valve is disposed between the source of pressurized fluid and the first chamber of the first hydraulic actuator and the third chamber of the second hydraulic actuator. A second directional control valve is disposed between the source of pressurized fluid and the second chamber of the first hydraulic actuator and the fourth chamber of the second hydraulic actuator. An accumulator may also be used to store pressurized fluid and selectively supply pressurized fluid to increase the efficiency of the work machine.

A fluid circuit for raising and lowering an implement including a quick drop valve member movable between at least a first position and a second position, the first position corresponding to a non-quick drop hydraulic fluid flow path of the fluid circuit and the second position corresponding to a quick drop hydraulic fluid flow path of the fluid circuit, the quick drop valve member being movable between at least the first and second positions based on pressures in the fluid circuit produced by hydraulic fluid. The fluid circuit further including a control system configured to selectively apply a biasing force against the quick drop valve member biasing the quick drop valve in the first position, the control system providing the biasing force independent of pressures in the fluid circuit produced by the hydraulic fluid.

Hydraulic quick drop circuit

A single stage, electrically controlled variable pressure relief valve assembly is provided that uses a valving element assembly slideably disposed within a housing having first and second inlet and outlet ports, the valving element assembly has a differential area defined thereon which acts in cooperation with an electrically controlled coil assembly to proportionally control the flow of fluid between the inlet port and an outlet ports of the housing. The valving element assembly has inlet and outlet ports that are oriented generally perpendicular to the flow of the fluid through the valving element assembly to effectively offset the effects of flow forces acting on the valving element.

Variable pressure relief valve

A method is provided for controlling displacement of a variable displacement pump coupled to a load. The method includes determining an electrical signal to be applied to a proportional solenoid for a desired pump displacement based on known pump characteristics. The electrical signal is provided to the proportional solenoid. The displacement of the variable displacement pump is controlled based on the electrical signal to the proportional solenoid.

Electro-hydraulic pump control system

A fluid system having a common source of pressurized fluid is provided to selectively control the speed and/or pressure of a first hydraulic circuit while also providing flow/pressure priority to a second hydraulic circuit. The first hydraulic circuit includes a first electrically controlled proportional relief valve connected between the source of pressurized fluid and a first fluid actuator and a second electrically controlled proportional relief valve connected between the reservoir and a point downstream of the first electrically controlled proportional relief valve. The second hydraulic circuit is connected to the source of pressurized fluid in parallel with the first hydraulic circuit.

Growing community of inventors

Joliet, IL, United States of America

David P Smith