Abstract: A hydrostatic transmission control system includes a controller that monitors inputs for shifting a transmission of a tractor to a different range gear; determines if an engine on the tractor is operating in a desired and acceptable shift range based on a sensed speed and a load of the engine, and determines if a hydrostatic transmission on the tractor is operating in a desired and acceptable shift range based on a sensed load and a speed of the hydrostatic transmission. If the controller determines the engine and the hydrostatic transmission are operating in the desired and acceptable shift range, the controller commands an oncoming clutch to ramp up and an off going clutch to ramp down, and synchronizes speeds of the engine and the hydrostatic transmission.

Abstract: An electrohydraulic actuator for a hydrostatic transmission includes a pair of pressure control valves between a hydraulic pressure inlet line and a pair of passages to a cylinder. A piston is positioned in the cylinder between the pair of passages and is slidable in response to hydraulic pressure in the cylinder on each side of the piston. A piston rod connects the piston to a joint which is connected to the trunnion lever of the hydrostatic transmission. A pedal position sensor provides electrical signals to an electronic controller that selectively actuates the pair of pressure control valves.

Abstract: A tractor ground positioning system includes ground positioning controls outside of an operator station of the tractor that can be actuated by an operator while maintaining contact with the tractor to move the tractor forward or reverse to connect an implement. A controller commands the tractor to move at a desired ground speed only while the operator continues actuating the controls.

Abstract: A tractor ground positioning system includes ground positioning controls outside of an operator station of the tractor that can be actuated by an operator while maintaining contact with the tractor to move the tractor forward or reverse to connect an implement. A controller commands the tractor to move at a desired ground speed only while the operator continues actuating the controls.

Abstract: A brake/differential lock pedal linkage includes a two-stage manual control that may lock a differential before progressively engaging a brake. The manual control may be a foot pedal or hand lever. The linkage may include a brake cam lever that pivots on a brake cam shaft in response to movement of the manual control, a differential lock link connected between the brake cam lever and an actuator that can move a differential lock shaft to lock the differential, and a lost motion coupling between the brake cam lever and the actuator allowing the brake cam lever to pivot to a differential lock position in which the actuator moves the differential lock shaft sufficiently to lock the differential, before the brake cam lever pivots further to progressively engage the brake.

Abstract: A brake/differential lock pedal linkage includes a two-stage manual control that may lock a differential before progressively engaging a brake. The manual control may be a foot pedal or hand lever. The linkage may include a brake cam lever that pivots on a brake cam shaft in response to movement of the manual control, a differential lock link connected between the brake cam lever and an actuator that can move a differential lock shaft to lock the differential, and a lost motion coupling between the brake cam lever and the actuator allowing the brake cam lever to pivot to a differential lock position in which the actuator moves the differential lock shaft sufficiently to lock the differential, before the brake cam lever pivots further to progressively engage the brake.

Abstract: A control system sets a set maximum speed of a utility vehicle, below the capable maximum speed of the vehicle, and recalibrates speed output signals corresponding to the set maximum speed. The system includes a microcontroller and a user-operated vehicle speed actuator, signal-connected to the microcontroller. The speed actuator is calibrated to actuate speeds, via the microcontroller, in a range from a minimum speed to a maximum speed. A user-operated speed set activator is used in conjunction with a ground speed sensor to set the set maximum speed. The microcontroller records the new maximum speed of the vehicle, and recalibrates the pedal position according to the new maximum speed.