Torque transmitting device control strategy for a nine speed transmission

• US 8,827,860 B2
• Filed: 12/02/2011
• Issued: 09/09/2014
• Est. Priority Date: 01/06/2011
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Mellet, Edward W., Wittkopp, Scott H.
• Primary Examiner(s): Holmes, Justin
• Assistant Examiner(s): FLUHART, STACEY A
• Application Number:
  US13/310,272
• Publication Number:
  US 20120178578A1
• Time in Patent Office: 1,012 Days
• Field of Search: 475/275, 475/296, 475/276, 475/254, 475/280, 475/330
• US Class Current: 475/254
• CPC Class Codes: F16H 2200/0065 the gear ratios comprising nine forward speeds
• CPC Class Codes: F16H 2200/2012 with four sets of orbital gears
• CPC Class Codes: F16H 2200/2046 with six engaging means
• CPC Class Codes: F16H 2312/04 Holding or hillholding
• CPC Class Codes: F16H 3/66 composed of a number of gear trains without drive passing from one train to another
• CPC Class Codes: F16H 3/666 with compound planetary gear units, e.g. two intermeshing orbital gears F16H3/663 takes precedence
• CPC Class Codes: F16H 61/0059 Braking of gear output shaft using simultaneous engagement of friction devices applied for different gear ratios

Abstract

A transmission includes an input member, an output member, four planetary gear sets, a plurality of coupling members and a plurality of torque transmitting devices. The transmission input member is connected to a dry launch clutch. Each of the planetary gear sets includes first, second and third members. The torque transmitting devices are for example clutches and brakes. A hill hold control strategy is provided for locking the transmission without using the dry launch clutch by selectively engaging combinations of the clutches and brakes.

Claims

1. A method for controlling a transmission in a motor vehicle, the method comprising:

providing a launch clutch;

providing the transmission having an input member connected to the launch clutch, an output member, first, second, third, and fourth planetary gear sets each having a first, a second, and a third member, wherein the second member of the first planetary gear set is connected with the second member of the second planetary gear set, the third member of the first planetary gear set is connected with the third member of the second planetary gear set and the first member of the third planetary gear set, the second member of the third planetary gear set is connected with the second member of the fourth planetary gear set, and the third member of the third planetary gear set is connected with the third member of the fourth planetary gear set, and wherein a first clutch connects the first member of the second planetary gear set with the third members of the third and fourth planetary gear sets, a second clutch connects the first member of the second planetary gear set with the first member of the fourth planetary gear set, a first brake connects the first member of the first planetary gear set with a stationary member, a second brake connects the second members of the first and second planetary gear sets with the stationary member, a third brake connects the first member of the third planetary gear set and the third members of the first and second planetary gear sets with the stationary member, and a fourth brake connects the third members of the third and fourth planetary gear sets with the stationary member;

commanding the transmission into a Drive mode of operation;

determining that the output shaft of the transmission should be rotationally fixed; and

engaging, in combinations of at least two at a time, the first clutch, the second clutch, the first brake, the second brake, the third brake, and the fourth brake in order to rotationally fix the output shaft.

2. The method of claim 1 wherein engaging the first clutch, the second clutch, the first brake, the second brake, the third brake, and the fourth brake in combinations of at least two includes engaging the third brake and the fourth brake to rotationally fix the output shaft.

3. The method of claim 1 wherein engaging the first clutch, the second clutch, the first brake, the second brake, the third brake, and the fourth brake in combinations of at least two includes engaging the first clutch, the second brake, and the third brake to rotationally fix the output shaft.

4. The method of claim 1 wherein engaging the first clutch, the second clutch, the first brake, the second brake, the third brake, and the fourth brake in combinations of at least two includes engaging the first clutch, the first brake, and third brake to rotationally fix the output shaft.

5. The method of claim 1 wherein determining that the output shaft of the transmission should be rotationally fixed includes sensing that the motor vehicle is at a negative speed and sensing that a throttle position or accelerator pedal position is below a predetermined value.

6. A method for controlling a transmission in a motor vehicle, the method comprising:

providing a launch clutch;

providing the transmission having an input member connected to the launch clutch, an output member, first, second, third, and fourth planetary gear sets each having a sun gear, a ring gear, and a carrier, wherein the ring gear of the first planetary gear set is connected with the ring gear of the second planetary gear set, the carrier of the first planetary gear set is connected with the carrier of the second planetary gear set and the sun gear of the third planetary gear set, the ring gear of the third planetary gear set is connected with the carrier of the fourth planetary gear set, and the carrier of the third planetary gear set is connected with the ring gear of the fourth planetary gear set, and wherein a first clutch connects the sun gear of the second planetary gear set with the carrier of the third planetary gear set and the ring gear of the fourth planetary gear set, a second clutch connects the sun gear of the second planetary gear set with the sun gear of the fourth planetary gear set, a first brake connects the sun gear of the first planetary gear set with a stationary member, a second brake connects the ring gears of the first and second planetary gear sets with the stationary member, a third brake connects the sun gear of the third planetary gear set and the carriers of the first and second planetary gear sets with the stationary member, and a fourth brake connects the carrier of the third planetary gear set and the ring gear of the fourth planetary gear set with the stationary member;

commanding the transmission into a Drive mode of operation;

determining that the output shaft of the transmission should be rotationally fixed; and

engaging, in combinations of at least two at a time, the first clutch, the second clutch, the first brake, the second brake, the third brake, and the fourth brake in order to rotationally fix the output shaft.

7. The method of claim 6 wherein engaging the first clutch, the second clutch, the first brake, the second brake, the third brake, and the fourth brake in combinations of at least two includes engaging the third brake and the fourth brake to rotationally fix the output shaft.

8. The method of claim 6 wherein engaging the first clutch, the second clutch, the first brake, the second brake, the third brake, and the fourth brake in combinations of at least two includes engaging the first clutch, the second brake, and the third brake to rotationally fix the output shaft.

9. The method of claim 6 wherein engaging the first clutch, the second clutch, the first brake, the second brake, the third brake, and the fourth brake in combinations of at least two includes engaging the first clutch, the first brake, and third brake to rotationally fix the output shaft.

10. The method of claim 6 wherein determining that the output shaft of the transmission should be rotationally fixed includes sensing that the motor vehicle is at a negative speed and sensing that a throttle position or accelerator pedal position is below a predetermined value.