Patent ID: 8292770

Claim:
An electric machine for use with an energy storage device, comprising a housing, a first rotor and a first stator electrically interactable with the first rotor carried within the housing, a second rotor and a second stator electrically interactable with the second rotor carried within the housing, a rotatable shaft carried by the housing and extending from the housing, a first continuously variable transmission including a first rotatable element, a second rotatable element and a mechanism for controlling the ratio of the rotation of the second element to the rotation of the first element, the first element of the first continuously variable transmission connected to the first rotor so that the first rotor rotates one-to-one with the first element and the second element of the first continuously variable transmission connected to the rotatable shaft of the electric machine so that the rotatable shaft rotates one-to-one with the second element, a second continuously variable transmission including a first rotatable element, a second rotatable element and a mechanism for controlling the ratio of the rotation of such second element to the rotation of such first element, the first element of the second continuously variable transmission connected to the second rotor so that the second rotor rotates one-to-one with such first element and the second element of the second continuously variable transmission connected to the rotatable shaft of the electric machine so that the rotatable shaft rotates one-to-one with such second element, and a controller electrically coupled to the first rotor and first stator and first mechanism and to the second rotor and second stator and second mechanism so as to modulate the rotation of the second element relative to the rotation of the first element of each of the first and second continuously variable transmissions for controlling the contributions of the first rotor and the second rotor to the rotatable shaft so as to enhance the efficiency of the electric machine.