Caterpillar Inc.

John R Connolly

Anil Shenoy

Kalyan Handique

Priyadarshini Gogoi

David P Smith

Kyle Gleason

Thomas J Hajek

Austin Payne

William Weiyeh Chow

Vishal Sharma

Edward William Mate

Chad Timothy Brickner

Brian Boniface

Chandrasekar Ramamoorthy

Rudy Van Mills

Sam Tuck

Randall A Harlow

Aleem Junaidi

Steven P Seaney

Anil Kumar R Shenoy

Ayoub E Maher

Paul Gilbert

Jun Wen

A hoist valve assembly for a work machine cylinder includes a main control valve, a counterbalance valve and a counterbalance shutoff valve. A main control valve raise position connects a head end of the cylinder with a pressurized fluid source and a rod end of the cylinder to a low pressure reservoir to extend the cylinder. The counterbalance valve is between the rod end and the main control valve, is biased to a closed position and has an open position connecting the rod end to the low pressure reservoir. Rod end and head end pressure signals apply force to the counterbalance valve toward the open position. The counterbalance shutoff valve is positioned between the head end and the counterbalance valve, and has a normal position to apply the head end pressure signal to the counterbalance valve and a shutoff position that blocks the head end pressure signal from the counterbalance valve.

Hoist system counterbalance valve signal shutoff

A system and method, wherein the system includes: an array of wells defined at a substrate, each well including an open surface and a well cavity and a fluid delivery module including a fluid pathway through which fluid flow is controlled along a fluid path in a direction parallel to the broad face of the substrate; and wherein the method includes: generating a set of genetic complexes within individual wells of the array of wells.

System and method for isolating and analyzing cells

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 machine is provided. The machine includes an engine, an engine speed sensor, a transmission, a transmission status sensor, a pump, and a controller. The engine speed sensor is configured to sense the speed of the engine. The transmission is coupled to the engine. The transmission status sensor is configured to sense the status of the transmission. The pump is coupled to the engine and has a first torque mode and a second torque mode. The controller is in communication with the engine speed sensor and the transmission status sensor and is operable to automatically switch the pump from the first torque mode to the second torque mode based on the engine speed and the transmission status.

System and method for controlling a machine

A hydraulic system is provided. The hydraulic system includes a source of pressurized fluid, a first control valve, a first actuator, a second control valve, a second actuator, and a relief. The first control valve is coupled to the source of pressurized fluid. The first actuator is coupled to the first control valve and has a first end and a second end. The second control valve is coupled to the source of pressurized fluid. The second actuator is coupled to the second control valve and has a first end and a second end. The relief has an input and an output, with the input coupled to the first end of the second actuator and the output coupled to the second end of the second actuator and the second end of the first actuator.

Method and apparatus for coordinated linkage motion

A valve stack for a work machine is disclosed. The valve stack has first and second valve bodies, each with first and second mounting surfaces and first and second valve members. The valve stack further has a third valve body with a mounting surface configured to engage the second mounting surfaces of the first and second valve bodies, and at least one valve member disposed within the third valve body. The at least one valve member is movable between a first position at which movement of a first operator control device corresponds to movement of the first valve member and movement of a second operator control device corresponds to movement of the second valve member, and a second position at which movement of the first operator control device corresponds to movement of the second valve member and movement of the second operator control device corresponds to movement of the first valve member.

Valve stack having a pattern switching valve

A single lever control assembly that limits motion due to the inherent design of the assembly. In other words, no additional components are required to limit the motion of the single lever control assembly. The assembly includes two U-shaped members each having a base and parallel legs extending from the base, a lever connected to one of the U-shaped members and a pivot block interconnecting the parallel legs for allowing the U-shaped members to rotate relative to one another. The assembly has at least one of the parallel legs having a projection that engages one of the parallel legs of the other U-shaped member. In general, the single lever control assembly is a type of modified universal joint whose movement is limited by a projection.

System for definable single lever control shift pattern joint

The present quick drop valve control provides both quick drop and float functions by moving a quick drop valve to a position interconnecting the drop and lift sides of a pair of lift cylinders when a directional control valve reaches a predefined position. The quick drop function valve is established by simultaneously energizing a first solenoid valve to communicate a shift end of the quick drop valve with a resolved pressure port of a resolver connected to the drop and lift sides and a first solenoid of a second solenoid valve to communicate a spring end of the quick drop valve with the drop sides so that the quick drop valve moves to the interconnecting position combining fluid expelled from the lift sides with fluid going to the drop side from a pump. The float function is established by simultaneously energizing the first solenoid valve to communicate the shift end of the quick drop valve with the resolved pressure port and a second solenoid of the second solenoid valve to communicate the spring end of the quick drop valve with the tank so that the quick drop valve moves to the interconnecting position effectively intercommunicating the pump, the tank and the lift sides and the drop sides of the lift cylinders.

Quick drop valve control

Growing community of inventors

Clayton, NC, United States of America

John R Connolly