Automated manual transmission clutch controller

• US 5,993,350 A
• Filed: 12/01/1997
• Issued: 11/30/1999
• Est. Priority Date: 12/01/1997
• Status: Expired due to Term

• Current Assignee: FCA US LLC (Stellantis NV)
• Original Assignee: Daimler Chrysler Corporation (Mercedes-Benz Group AG)
• Inventors: Reed, Richard G. Jr., Lawrie, Robert E., Rausen, David J.
• Primary Examiner(s): Marmor, Charles
• Assistant Examiner(s): Parekh, Ankur
• Application Number:
  US08/980,539
• Time in Patent Office: 729 Days
• Field of Search: 477/3, 477/5, 477/70, 477/77, 477/78, 477/79, 477/80, 477/86, 477/175, 477/176, 477/180, 180/65.2, 192/3.61, 192/3.62, 192/3.63, 192/3.56, 74/339, 74/335, 74/336 R, 74/473.12, 701/67, 701/53, 701/51
• US Class Current: 477/5
• CPC Class Codes: B60K 6/40 characterised by the assembly or relative disposition of components
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60K 6/547 the transmission being a stepped gearing
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/10 including control of change-speed gearings
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/40 Controlling the engagement or disengagement of prime movers, e.g. for transition between prime movers power-up or power-down of the driveline B60W30/192
• CPC Class Codes: B60W 2710/025 Clutch slip, i.e. difference between input and output speeds
• CPC Class Codes: B60W 2710/0644 Engine speed
• CPC Class Codes: B60W 30/18027 Drive off, accelerating from standstill
• CPC Class Codes: F16D 2500/10412 Transmission line of a vehicle
• CPC Class Codes: F16D 2500/1066 Hybrid
• CPC Class Codes: F16D 2500/3067 Speed of the engine
• CPC Class Codes: F16D 2500/30816 Speed of the input shaft
• CPC Class Codes: F16D 2500/30825 Speed of the output shaft
• CPC Class Codes: F16D 2500/3144 Accelerator pedal position
• CPC Class Codes: F16D 2500/7041 Position
• CPC Class Codes: F16D 2500/70426 Clutch slip
• CPC Class Codes: F16D 2500/70454 Engine speed
• CPC Class Codes: F16D 2500/70488 : Selection of the gear ratio
• CPC Class Codes: F16D 48/06 : Control by electric or electronic means, e.g. of fluid pressure
• CPC Class Codes: F16D 48/08 : Regulating clutch take-up on starting
• CPC Class Codes: F16H 2061/0422 : by an electric machine, e.g. by accelerating or braking the input shaft
• CPC Class Codes: F16H 61/0403 : Synchronisation before shifting
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y10S 903/919 : Stepped shift
• CPC Class Codes: Y10S 903/945 : Characterized by control of gearing, e.g. control of transmission ratio
• CPC Class Codes: Y10S 903/946 : Characterized by control of driveline clutch
• CPC Class Codes: Y10S 903/951 : Assembly or relative location of components
• CPC Class Codes: Y10T 74/19251 : Control mechanism
• CPC Class Codes: Y10T 74/19284 : Meshing assisters

Abstract

A powertrain system for a hybrid vehicle. The hybrid vehicle includes a heat engine, such as a diesel engine, and an electric machine, which operates as both an electric motor and an alternator, to power the vehicle. The hybrid vehicle also includes a manual-style transmission configured to operate as an automatic transmission from the perspective of the driver. The engine and the electric machine drive an input shaft which in turn drives an output shaft of the transmission. In addition to driving the transmission, the electric machine regulates the speed of the input shaft in order to synchronize the input shaft during either an upshift or downshift of the transmission by either decreasing or increasing the speed of the input shaft. When decreasing the speed of the input shaft, the electric motor functions as an alternator to produce electrical energy which may be stored by a storage device. Operation of the transmission is controlled by a transmission controller which receives input signals and generates output signals to control shift and clutch motors to effect smooth launch, upshift shifts, and downshifts of the transmission, so that the transmission functions substantially as an automatic transmission from the perspective of the driver, while internally substantially functioning as a manual transmission.

Claims

1. A hybrid transmission system for a vehicle having an engine operating at a speed defined in revolutions per minute (RPM), a drive wheel, a drive shaft connected to the drive wheel for rotating the drive wheel, comprising:

a transmission gear set, having an input shaft having an input shaft speed defined in revolutions per minute (RPM) and an output shaft, the input shaft being driven and driving the output shaft, the output shaft being adapted to cause motion of the drive wheel through the drive shaft, the input and output shafts having a plurality of gears which selectively mesh for engagement to vary a relative speed of rotation between the input shaft and the output shaft;

a plurality of shift motors to effect engagement and disengagement of the gears;

a clutch for selectively coupling the engine to the transmission;

a clutch motor for engaging and disengaging the clutch;

an electric machine connected to the input shaft for selectively increasing and decreasing the speed of the input shaft;

a transmission controller which receives a plurality of input signals and generates a plurality of output signals, the output signals controlling the motors and the electric machine in order to engage a new gear ratio between the input and output shafts and to synchronize the input and the output shafts just prior to engaging the new gear ratio; and

a clutch controller which generates a clutch command to control engagement and disengagement of the clutch in accordance with at least one of the plurality of input signals, the clutch controller determining whether the vehicle is in one of a launch and a shift condition, the clutch controller generating commands to substantially regulate the engine RPM during a launch condition and generating commands to substantially regulate slip during a shift condition.

2. The apparatus of claim 1 wherein in the launch condition, the clutch controller determines a desired clutch position in accordance with a disengaged clutch position, an engine throttle position, a launch difference, defined as the difference between the engine RPM and a desired launch engine RPM, and a mathematical derivative of the launch difference.

3. The apparatus of claim 2 wherein the clutch controller updates the desired clutch position iteratively until the throttle position is zero or the slip is below a predetermined threshold.

4. The apparatus of claim 1 wherein when the vehicle is in the shift condition and the clutch is being engaged, the clutch controller determines a desired clutch position in accordance with a position of the clutch when fully disengaged and a difference between an actual slip and a desired slip.

5. The apparatus of claim 4 wherein the clutch controller limits a change in the desired clutch position so the clutch cannot disengage rapidly during engagement.

6. The apparatus of claim 4 wherein the clutch controller calculates the desired slip by decrementing an initial slip value in accordance with the engine RPM and engine throttle position.

7. The apparatus of claim 4 wherein the clutch controller updates the desired clutch position iteratively until the slip falls below a predetermined threshold.

8. The apparatus of claim 1 wherein the input shaft, the output shaft, and the respective gears are substantially configured as a manual transmission.

9. The apparatus of claim 1 wherein the electric machine varies the speed of the input shaft so that the relative speeds of the input shaft and output shaft enables synchronization of the gears.

10. A hybrid transmission system for a vehicle having an engine operating at a speed defined in revolutions per minute (RPM), a drive wheel, a drive shaft connected to the drive wheel for rotating the drive wheel, comprising:

a transmission gear set, having an input shaft having an input shaft speed defined in revolutions per minute (RPM) and an output shaft, the input shaft being driven and driving the output shaft, the output shaft being adapted to cause motion of the drive wheel through the drive shaft, the input and output shafts having a plurality of gears which selectively mesh for engagement to vary a relative speed of rotation between the input shaft and the output shaft;

a plurality of shift motors to effect engagement and disengagement of the gears;

a clutch for selectively coupling the engine to the transmission;

a clutch motor for engaging and disengaging the clutch;

an electric machine connected to the input shaft for selectively increasing and decreasing the speed of the input shaft;

a transmission controller which receives a plurality of input signals and generates a plurality of output signals, the output signals controlling the motors and the electric machine in order to engage a new gear ratio between the input and the output shafts and to synchronize the input and the output shafts just prior to engaging the new gear ratio; and

a clutch controller which generates a clutch command to control engagement and disengagement of the clutch in accordance with at least one of the plurality of input signals the clutch controller determining a desired clutch position in accordance with a position of the clutch when fully disengaged and a difference between an actual slip, and a desired slip, the clutch controller limiting a change in the desired clutch position so the clutch cannot disengage rapidly during engagement, wherein the clutch controller calculates the desired slip by decrementing an initial slip value in accordance with the engine RPM and engine throttle position.

11. The apparatus of claim 10 wherein the clutch controller determines whether the vehicle is in one of a launch and a shift condition, the clutch controller generating commands substantially to regulate the engine RPM during a launch condition and generating commands substantially to regulate slip, defined as a difference between engine RPM and input shaft RPM, during a shift condition.

12. The apparatus of claim 11 wherein in a launch condition, the clutch controller determines a desired clutch position in accordance with a disengaged clutch position, an engine throttle position, a launch difference, defined as the difference between the engine RPM and a desired launch engine RPM, and a mathematical derivative of the launch difference.

13. The apparatus of claim 12 wherein the clutch controller updates the desired clutch position iteratively until the throttle position is zero or the slip is below a predetermined threshold.

14. The apparatus of claim 10 wherein the clutch controller updates the desired clutch position iteratively until the slip falls below a predetermined threshold.

15. The apparatus of claim 14 wherein the electric machine varies the speed of the input shaft so that the relative speeds of the input shaft and output shaft enables synchronization of the gears.