Abstract: A method for storing and reutilizing energy during operation of a hydrostatic actuator (EHA) having a hydraulic cylinder, a first bidirectional pump-motor rotationally coupled to an electric motor, and EHA valving and connections between the first pump-motor and the hydraulic cylinder. During at least one of two motoring quadrants, a hydraulic accumulator is charged using a second pump-motor whose rotation is driven by load-driven motoring of the first bidirectional pump-motor. During at least one of the pumping quadrants, driven rotation is imparted to the second pump-motor using stored energy from the accumulator, and said driven rotation of the second pump-motor is used to augment powered rotation of the first bidirectional pump-motor by the electric motor.

Abstract: An electro-hydrostatic actuator having a main circuit, a charging circuit and four different operating quadrants uses return flow from the main circuit to the charging circuit to charge an accumulator of the charging circuit during an actuator-retracting pumping quadrant and an actuator-retracting motoring quadrant of the actuator's four different operating quadrants. A charged state of the accumulator is used to deliver compensatory flows to the main circuit during at least some instances of an actuator-extending pumping quadrant and an actuator-extending motoring quadrant of the four different operating quadrants.

Abstract: An electro-hydrostatic actuator having a main circuit, a charging circuit and four different operating quadrants uses return flow from the main circuit to the charging circuit to charge an accumulator of the charging circuit during an actuator-retracting pumping quadrant and an actuator-retracting motoring quadrant of the actuator's four different operating quadrants. A charged state of the accumulator is used to deliver compensatory flows to the main circuit during at least some instances of an actuator-extending pumping quadrant and an actuator-extending motoring quadrant of the four different operating quadrants.

Abstract: A variable split displacement ratio axial piston machine, featuring a rotatable driveshaft, a tapered swashplate disposed around said rotatable driveshaft, a first working section disposed on a first side of the tapered swashplate, and a second working section disposed on a second side of the tapered swashplate. Each working section includes a respective set of pistons slidably received in a respective set of cylinder bores to draw and expel fluid into and from said cylinder bores. The first and second working sections respectively interface with first and second outer faces of the tapered swashplate in respective first and second facial planes. Tiltable adjustment of a working position of the tapered swashplate is operable to adjust respective orientations of the facial planes, which dictate relative piston stroke lengths of the piston sets. Such tiltable adjustment imparts control over a variable split displacement ratio between the working sections.

Abstract: A method for storing and reutilizing energy during operation of a hydrostatic actuator (EHA) having a hydraulic cylinder, a first bidirectional pump-motor rotationally coupled to an electric motor, and EHA valving and connections between the first pump-motor and the hydraulic cylinder. During at least one of two motoring quadrants, a hydraulic accumulator is charged using a second pump-motor whose rotation is driven by load-driven motoring of the first bidirectional pump-motor. During at least one of the pumping quadrants, driven rotation is imparted to the second pump-motor using stored energy from the accumulator, and said driven rotation of the second pump-motor is used to augment powered rotation of the first bidirectional pump-motor by the electric motor.

Abstract: A variable split displacement ratio axial piston machine, featuring a rotatable driveshaft, a tapered swashplate disposed around said rotatable driveshaft, a first working section disposed on a first side of the tapered swashplate, and a second working section disposed on a second side of the tapered swashplate. Each working section includes a respective set of pistons slidably received in a respective set of cylinder bores to draw and expel fluid into and from said cylinder bores. The first and second working sections respectively interface with first and second outer faces of the tapered swashplate in respective first and second facial planes. Tiltable adjustment of a working position of the tapered swashplate is operable to adjust respective orientations of the facial planes, which dictate relative piston stroke lengths of the piston sets. Such tiltable adjustment imparts control over a variable split displacement ratio between the working sections.