Electromotive drives
View Patent ↗A transmission having a plurality of tilting balls and opposing input and output discs provides an infinite number of speed combinations over its transmission ratio range. The transmission provides multiple powerpaths and can be combined with electrical components to provide motor/generator functionality, which reduces the overall size and complexity of the motor and transmission compared to when they are constructed separately. In one embodiment, rotatable components of a continuously variable transmission are coupled separately to an electrical rotor and to an electrical stator so that the rotor and stator rotate simultaneously in opposite directions relative to one another. In other embodiments, an electrical rotor is configured to transfer torque to or from a disc that is in contact with a plurality of speed adjusters, while an electrical stator is configured to transfer torque to a shaft that is operationally coupled to the speed adjusters via an idler.
1. A variable speed transmission having a longitudinal axis, comprising:
a plurality of balls distributed radially about the longitudinal axis, each ball having a tiltable axis about which it rotates;
an input disc in contact with the balls;
a rotatable idler coaxial about the longitudinal axis and positioned radially inward of and in contact with each of the balls;
an electric stator coupled to the rotatable idler;
an electric rotor coupled to the input disc; and
wherein the electric stator and the electric rotor are configured to rotate in opposite directions on axes coincident with the longitudinal axis.
2. The variable speed transmission of claim 1 , further comprising a plurality of permanent magnets attached to the input disc.
3. The variable speed transmission of claim 2 , wherein the input disc comprises a magnetic material.
4. The transmission of claim 1 , wherein the electrical stator and the electrical rotor rotate in opposite directions relative to one another, and wherein the electrical stator and the electrical rotor are configured to create an electromotive device.
5. The transmission of claim 4 , wherein a speed differential between the electrical stator and the electrical rotor creates a speed reduction through the transmission so that the output disc rotates more slowly in all ratios than the speed differential between the electrical stator and the electrical rotor.
6. The transmission of claim 4 , wherein the input disc increases speed when the output disc decreases speed.
7. The transmission of claim 1 , further comprising a cage rotatable about the longitudinal axis, the cage configured to position the balls axially and radially.
8. The transmission of claim 7 , wherein the electrical rotor is attached to the cage.
9. The transmission of claim 8 , wherein the electrical stator and the electrical rotor rotate in the same direction.
10. The transmission of claim 9 , wherein power exits through the output disc at a speed higher than the idler speed in all ratios.
11. The transmission of claim 9 , wherein the input disc is adapted to receive a torque from an external source.
12. The transmission of claim 11 , wherein the balls receive power from the input disc, the idler, and the cage to provide one or more functions of an infinitely variable transmission.
13. The transmission of claim 12 , where power exits through the output disc.
14. A variable speed transmission, comprising:
a plurality of balls distributed radially about a longitudinal axis, each ball having a tiltable axis about which the ball rotates;
an input disc in contact with each of the balls;
an output disc in contact with each of the balls;
an idler rotatable about the longitudinal axis and positioned radially inward of and in contact with each of the balls;
an electrical stator rotatable about the longitudinal axis and configured to receive electricity, the electrical stator attached to the idler, wherein the electrical stator transfers power to the idler; and
an electrical rotor rotatable about the longitudinal axis, the electrical rotor attached to the input disc, wherein the electrical rotor is configured to transfer power to the input disc.