Caterpillar Inc.

Shin Caterpillar Mistubishi Ltd

Eric Hughes

Matthew James Beschorner

Steven Conrad Budde

Amit Sharma

Mikhail A Sorokine

Thomas J Hajek

Aleksandar M Egelja

James Alvin Aardema

Eric Wade Cler

Brett J Janson

Andrew Nathan Schifferer

Rick D Vance

Benjamin Yoo

Justin Philip Pahl

Naoto Funabiki

Brad Van De Veer

Matt I Moul

Aleksandra M Egelja

Tomohiro Oyama

A control system for a machine is disclosed. The control system may have a bypass passage situated to allow fluid to bypass an actuator, and a warmup valve disposed within the bypass passage that is movable between flow-passing and-blocking positions. A controller is configured to move the warmup valve to the flow-passing position, fix a displacement position of the pump, compare the pressure of the fluid of the actuator with a threshold, and move the warmup valve to the flow-blocking position and reduce a pump outlet pressure when the pressure of the fluid is greater than the threshold. The controller may be configured to move the warmup valve to the flow-passing position, fix a displacement position of the pump, and adjust an input speed of the pump in response to the signal.

Machine control system having hydraulic warmup procedure

A method of operating a ride control system of a machine having an accumulator is provided. The method includes detecting a pressure at the accumulator. The method includes generating a first set of input data associated with a drive system and a brake pedal. The method includes generating a second set of input data associated with a lift cylinder. The method also includes determining a working mode of the ride control system based on the first set of input data and the second set of input data. The working mode of the ride control system includes a normal mode and an exposed mode. The method includes operating a ride control activation solenoid valve, upon determining the pressure at the accumulator to be above a predefined threshold, and the working mode of the ride control system to be the exposed mode.

Method of operating ride control system

A system can include one or more valve arrangements with a working chamber to receive a working fluid at a first pressure, and a control chamber to receive fluid at a second pressure. A dynamic seal can be disposed on a land of a valve element. The valve arrangement may include a sleeve against which the dynamic seal is slidably engaged. The valve element may include a check stem. A pressure compensating system may be in communication with bores formed in with the valve element. A pressure system to monitor dynamic seal wear may be in communication with the control chamber of the valve arrangement.

Hydraulic system with a dynamic seal

A system can include one or more valve arrangements with a working chamber to receive a working fluid at a first pressure, and a control chamber to receive fluid at a second pressure. A dynamic seal can be disposed on a land of a valve element. A supply passage can be in communication between the control chamber and a tank and can include a check valve. A relief valve can be disposed between the check valve and the control chamber. A pilot pump and another relief valve may be disposed upstream of the check valve. The relief valve downstream of the check valve can have a higher pressure limit than the downstream one. A pressure sensor may be disposed between the check valve and the control chamber and used to warn the operator of a high pressure in the control chamber.

Dynamic seal wear mitigation system

A system and method for calibrating an electronically actuatable hydraulic valve in a work machine may include at least one supply valve and at least one drain valve to be calibrated and a bypass valve in fluid communication with a pump and a fluid source. The at least one supply valve and the at least one drain valve may be calibrated by opening the at least one supply valve and the at least one drain valve, closing the bypass valve, setting the pump to a desired flow output, determining a first current command for the at least one supply valve corresponding to a first target pressure parameter and determining a second current command for the at least one drain valve corresponding to a second target pressure parameter.

System and method for calibrating hydraulic valves

A controller monitors groundspeed in an articulated machine and selectively disables an automatic articulation control function when the groundspeed is at or near zero. If there is an indication that an operator may not be aware that the automatic articulation control function is active by comparing when a on switch was activated compared to a machine power cycle or an operator not being present, the automatic articulation control function may be inactivated until the on switch is toggled. If the articulated machine is in neutral and the groundspeed is at or near zero, the automatic articulation control function may disabled. If the groundspeed is at or near zero but the transmission is not in neutral, the machine may simply be stalled to due working conditions and the automatic articulation control function may be maintained.

Automatic articulation machine states

An apparatus and method are provided for operating a motor grader having steerable front wheels and a front and rear frame pivotally connected at an articulation joint. The method includes selecting an automatic articulation mode, and commanding front wheel steering to turn the motor grader, providing a plurality of front wheel steering corrections to an electronic controller, filtering the plurality of front wheel steering corrections using a method for filtering steering corrections based on the constant curve mode, wherein the method generates filtered front wheel steering corrections, and automatically commanding articulation of the front frame relative to the rear frame about the articulation joint in response to the filtered front wheel steering corrections.

Path detection-based steering command filtering method for motor grader automatic articulation feature

A method for calibrating a valve having a valve element movable between a flow blocking position and a flow passing position includes pressurizing fluid directed to the valve, increasing a current directed to the valve for controlling a position of the valve element, and sensing a pressure of the fluid. The method for calibrating the valve also includes determining if a time-derivative of the sensed fluid pressure is greater than a predetermined threshold over a predetermined period of time, and determining a cracking point current command directed to the valve. The cracking point current command is directed to the valve when the time-derivative of the sensed fluid pressure is greater than the predetermined threshold.

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Metamora, IL, United States of America

Eric Hughes