Electrically actuated synchronizer for a vehicle transmission

A synchronizer for a vehicle transmission, said synchronizer synchronizing the speed of a shift gear with the speed of an output shaft of the transmission, said synchronizer comprising:

• a cylindrical sleeve including an inner surface and an outer surface, said sleeve including sleeve splines on the inner surface of the sleeve;
• a rotor rotatably mounted to the outer surface of the sleeve;
• a shift collar mounted to the inner surface of the sleeve and being threadably coupled to the rotor, said shift collar including shift collar splines that mesh with the sleeve splines;
• and
• an electric coil electrically coupled to the rotor, said coil being responsive to an electric current so as to cause the rotor to rotate in either a clockwise or counterclockwise direction on the outer surface of the sleeve, wherein rotation of the rotor in the clockwise direction causes the shift collar to move in one axial direction relative to the sleeve and rotation of the rotor in the counter-clockwise direction causes the shift collar to move in an opposite axial direction.

A method of synchronizing the speed of a shift gear in a transmission to the speed of an output shaft of the transmission, comprising:

• slidably mounting a shift collar to an inner surface of a sleeve;
• rotatably mounting a rotor to an outer surface of the sleeve, said rotor being mechanically coupled to the shift collar;
• and
• applying a current in a predetermined direction to a coil, said coil being electrically coupled to the rotor so as to cause the rotor to rotate on the sleeve and cause the shift collar to move in an axial direction relative to the sleeve.