Case Corporation

Michael Stelzle

William L Schubert

William A Itzenhuiser

Donald D Carr

A load sensor is provided on a tractor to sense a load in the upper link of a three point hitch. The load sensor is fixed to the upper link, rather than the tractor to move with the upper link rather than the tractor. This arrangement permits the load sensor to always indicate the longitudinal load placed on the upper link.

Upper link sensing

A control system is disclosed for controlling a power takeoff (PTO) shaft of a work vehicle (e.g., a tractor). The work vehicle includes an engine and an operator station, and the PTO shaft transfers power from the engine to an implement. The control system includes a remote switch, a vehicle speed sensor, and a control circuit. The remote switch is located remotely from the operator station and provides a remote switch signal to the control circuit to engage and disengage rotational movement of the PTO shaft. The vehicle speed sensor provides a vehicle speed signal to the control circuit representative of a speed of the work vehicle. The control circuit receives the remote switch signal and the vehicle speed signal and, when the vehicle speed signal exceeds a predetermined vehicle speed, the control circuit prevents engagement and disengagement of the PTO shaft with the remote switch.

Power takeoff control switches

Power takeoff control system

A method of automatically controlling a power takeoff shaft of a work vehicle having a hitch includes automatically initiating engagement of the power takeoff shaft as the hitch is lowered such that the power takeoff shaft reaches clutch lockup approximately at a predetermined hitch position setpoint. A method of controlling the engagement of a power takeoff shaft of a work vehicle having a hitch includes calculating a hitch drop time from a first hitch position to a second hitch position based on a hitch drop rate, comparing the hitch drop time to a power takeoff shaft engagement time, and decreasing the hitch drop rate if the power takeoff shaft engagement time is greater than the hitch drop time.

Automatic power takeoff control system

A control system for controlling a power takeoff shaft of a work vehicle having a hitch includes a hitch position sensor and a control circuit. The hitch position sensor is configured to generate a hitch position signal. The control circuit is coupled to the hitch position sensor and is configured to receive the hitch position signal, to compare the hitch position signal to a first predetermined hitch position and a second predetermined hitch position, to engage the power takeoff shaft when the hitch crosses the first predetermined hitch position and to disengage the power takeoff shaft when the hitch crosses the second predetermined hitch position.

Multiple setpoint power takeoff control system

A hitch assembly control system for an off-highway vehicle such as an agricultural tractor is operable in both position and draft control modes. The control system is capable of transitioning from the position mode to the draft mode, and from the draft mode to the position mode, under particular conditions. For the transition from position to draft mode, these conditions include a target hitch position being greater than both a hitch position command and a hitch position feedback. For the transition from draft to position mode, these conditions include the hitch position command being greater than the hitch position plus a hysteresis factor, or less than the hitch position command that existed back at the transition into the draft mode.

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Aurora, IL, United States of America

Michael Stelzle