Electronic ride control system for off-road vehicles

An excavator comprising:

• a wheeled vehicle;
• an implement movably supported by the vehicle;
• a hydraulic fluid source supported by the vehicle;
• a hydraulic actuator coupled between the implement and vehicle to lift the implement relative to the vehicle;
• an electronic valve coupled to the source and the actuator to control the flow of hydraulic fluid applied to the actuator by the source;
• means for generating a pressure signal representative of the pressure in the actuator;
• means mechanically coupled between the implement and the wheeled vehicle for generating a position signal representative of the position of the implement with respect to the wheeled vehicle;
• and
• an electronic controller coupled to the electronic valve, the means for generating a pressure signal, and the means for generating a position signal, the controller applying control signals derived from the pressure signal and the position signal to the electronic valve to cause the electronic valve to control the flow of hydraulic fluid applied to the actuator to maintain the pressure signal substantially constant.

A control system for reducing the oscillation of a work vehicle as it moves across a surface, the work vehicle of the type including an implement moveable relative to the vehicle, the system comprising:

• a hydraulic fluid source;
• a hydraulic actuator couplable between the vehicle and the implement to lift the implement;
• an electronic valve coupled to the source and the actuator to control the flow of hydraulic fluid applied to the actuator by the source;
• a pressure transducer in fluid communication with the hydraulic fluid applied to the actuator to generate a pressure signal related to the pressure in the actuator;
• a position transducer mechanically coupleable between the implement and the vehicle to generate a position signal representative of the position of the implement with respect to the vehicle;
• and
• an electronic controller coupled to the electronic valve, the pressure transducer, and the position transducer, the controller generating valve command signals based upon the pressure signal and the position signal and applying the command signals to the electronic valve to cause the electronic valve to control the flow of hydraulic fluid applied to the actuator to reduce the oscillation of the work vehicle as it moves across the surface.