Caterpillar Inc.

Charles W Birchenough

Lorne W Tweed

Noel J Rytter

Hans P Dietz

Dennis A Barney

Rolland D Scholl

Kenneth P Liesener

Dwight S Holloway

James B McKnight

Brian James Oleson

Sean E Carey

Jeffrey A Champa

The temperature of a machine component is controlled by transferring heat generated by a torque converter under restricted conditions to the component. The machine includes a circulating fluid system configured to transfer heat from the torque converter to the remotely positioned machine component. A controller is configured to sense the temperature of the component, and to restrict motion of the torque converter turbine when the sensed temperature is below a desired temperature. Heat generated by the torque converter under the restricted condition is transferred through the circulating fluid system to the remote component, such as the machine power source, to control the temperature thereof.

System and method for controlling machine component temperatures

A method and apparatus is configured for calibrating a fluid retarder in a transmission system. The transmission system may include an engine connected to a transmission through a driveshaft or power input shaft. The driveshaft is mechanically connected to the fluid retarder The fluid retarder includes a rotor mechanically connected to the driveshaft and a retarder valve adapted to enable fluid flow across the rotor The method includes the steps of delivering a valve command to the retarder valve, determining a speed of the engine, and calibrating the retarder valve in response to the engine speed, and the valve command.

Method and apparatus for calibrating a fluid retarder

The present invention provides a sensing system and method for providing information relating to a drivetrain during shifting operations. The drivetrain includes an engine, a torque converter and a transmission. The system includes sensors for detecting the output speed of the engine, the output speed of the torque converter, and the output speed of the transmission. The system detects the starting condition of a shifting operation, responsively determines a set of performance parameters, and produces a set of performance parameter signals.

Method and system for diagnosing a drivetrain during shifting operations

A control system is provided for a vehicle regulating engine speed during shifts so as to reduce driveline torque and shift shock. The control system includes separate microprocessor based engine and transmission controllers which communicate via a data link. When a shift is initiated, the transmission controller delays a first period of time CTSDELAY sufficient for the transmission to disengage the old gear ratio and then produces a CTSSPEED signal. The transmission controller continues to produce the CTSSPEED signal for a second period of time CTSDUR which corresponds to the time required for the transmission to engage the new gear ratio. The engine controller receives the desired engine speed signal and regulates engine speed into correspondence with the desired speed. During upshifts, the CTSSPEED signal is set to a speed which is a predetermined amount above the synchronization speed of the new gear for an upshift. Conversely, during downshifts, the CTSSPEED is set to a speed which is a predetermined amount below the synchronization speed in the new gear. The control system preferably includes a unit [means] for sensing a lockup time period corresponding to the time required for the transmission to lock up in the new gear ratio. The control system is capable of modifying the second time period CTSDUR as a function of the sensed lockup time period.

Integrated engine and transmission control system

Growing community of inventors

Morton, IL, United States of America

Charles W Birchenough