Continuously variable gear transmission

An apparatus for facilitating control of a speed ratio of a continuously variable transmission (CVT), the speed ratio of the CVT being controlled based on a tilt angle of each of a plurality of ball axles of a plurality of traction balls of the CVT, the apparatus comprising:

• a non-rotatable first member having a first plurality of first angular grooves arranged angularly about an axis, the first plurality of first angular grooves configured to engage first ends of a plurality of ball axles of a plurality of traction balls of the CVT, the non-rotatable first member being non-rotatable about the axis;
• a rotatable second member coaxial with the first member and having a second plurality of second angular grooves arranged angularly about the axis, the second plurality of second angular grooves configured to engage second ends of the plurality of ball axles of the plurality of traction balls of the CVT, the rotatable second member being rotatable about the axis;
• and
• an actuator coupled to the rotatable second member for rotating the second member about the axis, the rotating the second member about the axis changing angular alignment of the first plurality of first angular grooves relative to the second plurality of second angular grooves, the changing the angular alignment of the first plurality of first angular grooves relative to the second plurality of second angular grooves first causing angular skewing of the plurality of ball axles to a rotational misalignment angle relative to the axis in a rotational direction, the angular skewing of the plurality of ball axles to the rotational misalignment angle relative to the axis in the rotational direction during operation of the CVT second causing both (a) angular deskewing of the plurality of ball axles relative to the axis in the rotational direction towards a zero misalignment angle relative to the axis in the rotational direction and (b) tilting of the plurality of ball axles relative to the axis in the rotational direction as the plurality of ball axles return towards the zero misalignment angle relative to the axis in the rotational direction, the tilting occurring as the plurality of ball axles move within the first plurality of first angular grooves and the second plurality of second angular grooves, thereby changing the ratio of the CVT.