Abstract: The present invention is a crane operating system and method which monitors the crane moment load in order to keep the crane within the safe operating envelope. In determining the current crane moment load the system considers boom raising cylinder pressure, boom angle, chassis incline, as well as hydraulic pressure.

Abstract: A rock crusher includes a bowl coupled to a frame and a head assembly coupled to the frame defining a crushing gap between the head assembly and the bowl. The rock crusher further includes a number of fixed displacement hydraulic motors adapted to rotate the bowl with respect to the frame and a hydraulic fluid source providing a flow rate of hydraulic fluid to the hydraulic motors. A hydraulic control valve is adapted to remove one of the hydraulic motors from operation, directing the hydraulic fluid to the remaining hydraulic motors. The flow rate of hydraulic fluid remains unchanged, thereby increasing the hydraulic fluid flow rate provided to and the speed of the remaining hydraulic motors.

Abstract: A rock crusher includes a bowl coupled to a frame and a head assembly coupled to the frame defining a crushing gap between the head assembly and the bowl. The rock crusher further includes a number of fixed displacement hydraulic motors adapted to rotate the bowl with respect to the frame and a hydraulic fluid source providing a flow rate of hydraulic fluid to the hydraulic motors. A hydraulic control valve is adapted to remove one of the hydraulic motors from operation, directing the hydraulic fluid to the remaining hydraulic motors. The flow rate of hydraulic fluid remains unchanged, thereby increasing the hydraulic fluid flow rate provided to and the speed of the remaining hydraulic motors.

Abstract: A method and apparatus for controlling an agricultural harvester having a cut crop receiving header coupled to a hydraulic cylinder. The header applies a force against the ground that is adjusted by applying pressure to the cylinder. A first proportional valve is fluidly coupled to the cylinder, and responds to a first input signal by increasing pressure in the cylinder to a setpoint value, when the pressure is less than the setpoint. A second proportional valve is also fluidly coupled to the cylinder, and responds to a second input signal by reducing pressure in the cylinder to the setpoint pressure value, when the pressure is greater than the setpoint. A pressure signal representing cylinder pressure is received. The difference between the measured pressure and the setpoint is used to compute the first and second input signals, which are transmitted to the valves.