Granted Patent B1

US 7,302,330 · App. 11/515,517 · Granted Nov 27, 2007

Abstract

Claims (123)

1. A method of dynamically controlling pressure to a torque converter clutch (TCC) of a torque converter coupled to a transmission, comprising:

monitoring throttle position;

monitoring engine speed;

controlling pressure to the torque converter clutch to increase slip after the throttle position indicates a tip-in has occurred and when engine speed is low;

regulating at least one of a transmission steady state pressure to the transmission and pressure to the torque converter to maintain the increased slip; and

controlling pressure to the torque converter to reduce slip by engaging the torque converter clutch.

2. The method of claim 1 further comprising:

operating in at least one of a an inactive mode, a target determination mode, a maintain mode, a pressure correction mode, and a pressure regulation mode;

transitioning between the at least one of the inactive mode, the target determination mode, the maintain mode, the pressure correction mode, and the pressure regulation mode based on at least one of throttle position, engine speed, transmission temperature, turbine speed, and a TCC On request; and

wherein the controlling and the regulating are based on the one of the inactive mode, the target determination mode, the maintain mode, the pressure correction mode, and the pressure regulation mode.

3. The method of claim 1 further comprising:

determining a target engine speed, a target engine torque, and a target slip error based on throttle position;

and wherein the controlling and the regulating are based on the target values.

4. The method of claim 2 further comprising:

determining a throttle gradient from a first throttle position and a second throttle position;

determining a filtered throttle gradient based on a first throttle gradient and a second throttle gradient; and

wherein the transitioning is based on the throttle gradient and the filtered throttle gradient.

5. The method of claim 4 wherein the throttle gradient (TG) is calculated based on a first throttle position at time T (T T ), a second throttle position at time T−1 (T T−1 ), a current execution time (Loop Rate), and from an equation:

TG

=

T

T

-

T

T

-

1

Loop

⁢

⁢

Rate

.

6. The method of claim 4 wherein the filtered throttle gradient (TG Filt ) is calculated based on constants (K1 and K2), a first throttle gradient (TG), a second throttle gradient that is calculated previous (TG prev ) to the first throttle gradient (TG), and from an equation:

TG

Filt

=

(

K

⁢

⁢

1

*

TG

+

K

⁢

⁢

2

*

TG

prev

)

(

K

⁢

⁢

1

+

K

⁢

⁢

2

)

.

7. A dynamic torque converter clutch control system, for torque converters coupled to a transmission, comprising:

a dynamic mode module that selects a current mode from an inactive mode, a target determination mode, a pressure regulation mode, and a pressure correction mode;

a target determination module that determines target values for engine speed, engine torque, and slip error based on the current mode and throttle position; and

a torque convert clutch pressure control module that controls pressure to the torque converter clutch based on the current mode and the target values for engine speed, engine torque, and slip error.

8. The system of claim 7 further comprising a steady state pressure module that controls a steady state pressure to the transmission based on the mode.

9. The system of claim 7 wherein the dynamic mode module selects the mode based on at least one of throttle position, engine speed, transmission temperature, turbine speed, and a TCC mode request.

10. The system of claim 9 wherein the torque converter clutch pressure control module controls pressure to the torque converter to increase slip when in the target determination mode; to maintain the increased slip when in the maintain mode; and to decrease slip when in the pressure regulation mode.

11. The method of claim 9 wherein the torque converter control pressure control module corrects pressure to the torque converter clutch based on a comparison of actual engine torque and the target value for engine torque when in the pressure correction mode.

12. The system of claim 8 wherein the steady state pressure module controls a steady state pressure to the transmission based on a maximum of a determined steady state pressure, a steady state line pressure at time T−1, a base pressure plus a throttle modifier, and a base pressure plus a throttle modifier for torque converter clutch.

13. The system of claim 12 wherein the steady state pressure module controls a steady state pressure by decreasing pressure according to a determined time ratio.

14. The system of claim 7 wherein the dynamic mode module determines a current mode based on a throttle gradient and a filtered throttle gradient.

15. The system of claim 14 wherein the dynamic mode module calculates the throttle gradient (TG) based on a first throttle position at time T (T T ), a second throttle position at time T−1 (T T−1 ), a current execution time (Loop Rate), and from an equation:

TG

=

T

T

-

T

T

-

1

Loop

⁢

⁢

Rate

.

16. The system of claim 14 wherein the dynamic mode module calculates a filtered throttle gradient (TG Filt ) based on constants (K1 and K2), a first throttle gradient (TG), a second throttle gradient that calculated previously (TG prev ), and from an equation:

TG

Filt

=

(

K

⁢

⁢

1

*

TG

+

K

⁢

⁢

2

*

TG

prev

)

(

K

⁢

⁢

1

+

K

⁢

⁢

2

)

.

17. The system of claim 7 wherein the dynamic mode module governs transitions between at least one of the inactive mode, the target determination mode, the pressure regulation mode, and the pressure correction mode based on the current mode.

Assignments (12)