Caterpillar Inc.

Caterpillar Tractor Co.

Todd D Creger

Randall M Mitchell

Douglas A Carlson

James R Talbott

Richard B League

Gregory L Williamson

Javad Hosseini

Alan L Stahl

Ronnie L Satzler

Hans P Dietz

Paul L Wright

Kenneth P Liesener

John M Hadank

Sri K Rangarajan

William O Jankovsky

James Thomas Ferrier

Jeffery L Scott

Steven R Nelson

Wayne M Ferrell

David M Spurlock

A hydraulic clutch/brake mechanism has an actuator piston assembly therein to control actuation of the associated clutch/brake. The actuator piston assembly has a damping arrangement disposed therein that is operative to damp the movement of the actuator piston assembly relative to a plurality of disks located therein and to establish an end-of-fill.

Cushioned hydraulic clutch/brake piston

A method and apparatus for determining a value of torque at a desired location on a machine. The method and apparatus includes choosing the desired location, determining an operating condition relevant to the desired location, determining a plurality of parameters of the machine, and determining a value of torque at the desired location as a function of the operating condition and the plurality of parameters.

Method and apparatus for determining torque at desired locations on a machine

A simplified method and system for determining a loading condition on a powertrain of a machine resulting from a loading condition on an implement thereof. The method includes the steps of inputting a predetermined plurality of parameter signals representative of the loading condition on the implement into an implement loading model to determine a plurality of implement loading modeled values as a function of the inputted loading parameter signals and inputting the implement loading modeled values into a kinematic linkage model to determine a plurality of modeled linkage loading values as a function of the inputted implement loading modeled values and a plurality of known linkage parameter values and inputting the modeled linkage loading values into a machine powertrain loading model to determine a plurality of powertrain loading modeled values indicative of the loading condition on the powertrain.

Simplified powertrain load prediction method and system using computer based models

A method and apparatus for controlling a hitch system on a work machine, the hitch system having a work implement attached. The method and apparatus includes determining at least one force applied to at least one of the work machine and the work implement, determining at least one distance from a predetermined point on the hitch system to a desired at least one point on at least one of the work machine and the work implement, calculating at least one moment for at least one of the work machine and the work implement, responsively determining a desired pressure to apply to a powered linear actuator located on the hitch system to obtain a desired load distribution point on the work machine, and applying the desired pressure to the powered linear actuator.

Method and apparatus for controlling a hitch system on a work machine

A method for controlling the displacement of a variable displacement hydraulic pump to produce a desired flow of fluid is disclosed. The method includes the steps of: determining that the machine is being operated in a digging cycle; determining a desired displacement of the pump, the desired pump displacement being less than the maximum pump displacement; and controlling the pump displacement to the desired pump displacement to produce a desired flow of fluid.

Apparatus and method for controlling a variable displacement pump

An electrohydraulic control device for a drive train of a machine is disclosed. The machine includes an engine, a torque converter having an impeller element, a reactor element and a turbine element, an impeller clutch drivingly connected between the engine and the impeller element, and a set of service brakes. An impeller brake is drivingly connected between the impeller element and a stationary support member. A controller receives at least one input signal representing an operation of the drive train and responsively controls one of the impeller clutch, impeller brake and brake set.

Electrohydraulic control device for a drive train of a machine

Apparatus and method for estimating an attribute associated with a mobile machine. The machine has an engine and a powertrain. The powertrain includes a torque converter coupled to the engine. The apparatus and method sense a plurality of parameters of the machine and responsively produce a plurality of respective parameter signals and calculating an estimated value of the attribute as a function of the parameter signals using a computer based model. The apparatus and method further calculates first and second estimated values of a torque converter input torque, compares the first and second torque converter input torque estimate signals and responsively calibrates the computer based model.

Apparatus and method for calibrating a computer based model of an

An apparatus and method for periodically cleaning the fins of a radiator of an internal combustion engine using a nozzle system with at least one nozzle directed toward the fins, and a cleaning agent delivery system connected to the nozzle system. The apparatus determines the presence of airflow resistance through the fins, generates an airflow resistance signal, delivers the airflow resistance signal to a control system, and delivers a control signal to the cleaning agent delivery system.

Apparatus and method for cleaning radiator fins

In one aspect of the present invention, a method for determining an estimate of a torque of a powertrain at a point M using a computer based model is provided. The powertrain includes a driveline and an engine. The method includes the steps of sensing a plurality of parameters of the powertrain in realtime during operation and responsively producing a plurality of respective parameter signals, and receiving the parameter signals, determining a modeled value of the torque, and responsively producing a torque signal.

Method for determining an estimate of a driveline torque using a

In one aspect of the present invention, a method of effecting shifts in a vehicle is disclosed. The method modifies the transmission shiftpoints in response to the number of upshift successes and failures.

Method for modifying the shiftpoints of an automatic transmission

The present invention is directed toward determining when a clutch of an automatic transmission substantially fills with fluid. Once it is accurately determined when a clutch fills with fluid, then control over the transmission shifting may reliably be performed. The present invention determines when an on-coming speed clutch substantially fills with fluid in response to determining when an off-going speed clutch releases. Further, the present invention determines when an on-coming direction clutch substantially fills with fluid in response to determining when the torque converter output torque suddenly changes.

Method for determining the fill time of a transmission clutch

In one aspect of the present invention, a method of effecting shifts in a vehicle is disclosed. The method modifies the transmission shiftpoints in response the wheel power of the vehicle in order to optimize vehicle shifting, while reducing the potential for shift cycling.

The present invention relates to an adaptive control method for an automatic transmission. The method includes the steps of:

Adaptive control method for an automatic transmission

In one aspect of the present invention, an electronic shift control for a powershift transmission is disclosed. The transmission includes a plurality of speed and direction changing clutches. A plurality of pressure control valves are individually connected to the clutches. A hydraulic pump delivers pressurized hydraulic oil to predetermined pressure control valves to meter hydraulic fluid in response to receiving a clutch command signal. The method produces a shift from a first transmission ratio to a second transmission ratio through disengagement of an off-going clutch associated with the first transmission ratio and engagement of an on-coming clutch associated the second transmission ratio. The method includes filing an on-coming speed clutch, releasing an off-going direction clutch in response to the on-coming speed clutch being filled, and thereafter, gradually increasing the on-coming speed clutch pressure to engage the speed clutch. Finally, the on-coming direction clutch pressure is gradually increased to engage the direction clutch in response to the on-coming speed clutch being engaged.

Method of controlling clutch-to-clutch shifts for a powershift

An apparatus for controlling the fluid flow delivered to work elements of a work vehicle. In the operation of hydraulic work vehicles, when quick or multiple implement movement is required, the fluid pumps often are requested to surpass their capability in providing fluid flow to the work elements. A flow-limiting situation then occurs wherein some of the work elements are not receiving the requested flow and therefore cannot perform their requested functions. To solve this problem, the total available flow and the total requested flow from the pumps are monitored. If the total requested flow is not great enough to cause a flow-limiting situation, the operators demands are communicated to control valves which control fluid flow to the respective work elements. However, if the total requested flow is greater than the total available flow, the operators demand signals are 'scaled down' in order to prevent a flow-limiting situation. The signals are communicated to the control valves in proportion to the operator demand. Therefore, the work elements move precisely as the operator demands even under high load conditions. This apparatus proves particularly useful on machines such as hydraulic excavators, where multiple work elements are used simultaneously, and precise controllability is desired.

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Metamora, IL, United States of America

Todd D Creger