Working vehicle
AssigneeJ.C. Bamford Excavators Limited
InventorsStephen De Caen, Jonathan Christopher Boustred
Life of this patent
Estimating the term…
Abstract
A working vehicle includes an electric storage device; a traction motor configured to propel the working vehicle and to generate electrical energy when braking; a hydraulic system including a hydraulic pump driven by a load motor, a hydraulic actuator and a control valve; and a control system. The control system is configured to determine a state of charge of the electric storage device; induce additional load on the hydraulic system by directing the load motor to drive the hydraulic pump and actuating the control valve to direct flow of hydraulic fluid to the hydraulic actuator when the state of charge is at or above a predetermined threshold.
Claims17
A method of controlling electrical energy in a working vehicle, the working vehicle comprising:
- an electric storage device;
- a traction motor having a driving state, in which the traction motor is configured to propel the working vehicle using power from the electric storage device, and a regenerative braking state, in which the traction motor is configured to perform regenerative braking and generate electrical energy;
- a hydraulic system comprising a hydraulic pump, a hydraulic actuator and a control valve for controlling flow of hydraulic fluid between the hydraulic pump and the hydraulic actuator;
- and a load motor configured to drive the hydraulic pump, the method comprising:
- determining a state of charge of an electric storage device of the working vehicle;
- generating electrical energy by a traction motor of the working vehicle;
- inducing additional load on the hydraulic system by directing a load motor of the working vehicle to drive a hydraulic pump of the working vehicle and directing a control valve of the working vehicle to permit flow of hydraulic fluid from the hydraulic pump to a hydraulic actuator of the working vehicle when it is determined that an amount of charge in the electric storage device is at or above a predetermined threshold;
- and
- determining an extension state of the hydraulic actuator, such that:
- when it is determined that the amount of charge in the electric storage device is at or above the predetermined threshold and that the hydraulic actuator is fully extended, the load motor is directed to drive the hydraulic pump and the control valve is actuated to direct hydraulic fluid from the hydraulic pump to urge the hydraulic actuator in an extending direction;
- and/or
- when it is determined that the amount of charge in the electric storage device is at or above the predetermined threshold and that the hydraulic actuator is fully retracted, the load motor is directed to drive the hydraulic pump and the control valve is actuated to direct hydraulic fluid from the hydraulic pump to urge the hydraulic actuator in a retracting direction.
Dependencies are inferred from the claim text.