Transmission and method of engagement
AssigneeFord Global Technologies, LLC
InventorsScott Patrick Ries, Kendrick Morrison
Life of this patent
Estimating the term…
Abstract
While a transmission range selector is in a Park position, a controller engages multiple transmission shift elements to place the transmission in a tie-up state. In the tie-up state, both the transmission output shaft and the turbine shaft are held against rotation by the shift elements. To transition from Park to Drive, the controller releases one of the shift elements to place the transmission in a 1st gear state. To transition from Park to Reverse, the controller releases a different one of the shift elements to place the transmission in a reverse state. The controller may wait until the driver releases the brake pedal to release the shift element.
Claims13
A transmission comprising:
- a first brake or clutch which is engaged in a park state and a forward launch state and disengaged in a reverse launch state;
- and
- a second brake or clutch which is engaged in the park state and the reverse launch state and disengaged in the forward launch state.
A transmission comprising:
- a first shift element which is engaged in a park state and a forward launch state and disengaged in a reverse launch state;
- a second shift element which is engaged the park state and the reverse launch state and disengaged in the forward launch state;
- and
- a third shift element which is engaged in the park state, the forward launch state, and the reverse launch state.
Dependencies are inferred from the claim text.