An electro-mechanical drive apparatus uses a single variable speed motor, two one-way clutches, a hydraulic pump stack and a hydraulic accumulator to provide both hydraulic power for linear motion axes and rotation of a driven element of an electromechanical drive system in an injection molding machine. When engaged, the first one-way clutch couples the drive motor to the pump stack, while the second one-way clutch couples the motor to the driven element. During rotation of the drive motor in a forward direction, (a) the first one-way clutch engages, rotating the shaft of the hydraulic pump stack to power the machine's hydraulic systems and charge an accumulator; and (b) the second one-way clutch slips. When the drive motor is rotated in a reverse direction, (a) the second one-way clutch engages, rotating the driven element, and (b) the first one-way clutch slips.