Method for controlling slip on a clutch assigned to an automatic transmission

• US 20030220172A1
• Filed: 05/21/2003
• Published: 11/27/2003
• Est. Priority Date: 05/22/2002
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Luh, Joachim
• Granted Patent: US 7,022,043 B2
• Time in Patent Office: Days
• US Class Current: 477/175
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/10 including control of change-speed gearings
• CPC Class Codes: B60W 2510/0638 Engine speed
• CPC Class Codes: B60W 2510/0657 Engine torque
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2710/025 Clutch slip, i.e. difference between input and output speeds
• CPC Class Codes: B60W 2710/027 Clutch torque
• CPC Class Codes: B60W 30/18 Propelling the vehicle
• CPC Class Codes: B60W 30/1819 Propulsion control with control means using analogue circuits, relays or mechanical links
• CPC Class Codes: F16H 2061/6618 Protecting CVTs against overload by limiting clutch capacity, e.g. torque fuse
• CPC Class Codes: F16H 2342/044 Torque transmitting capability
• CPC Class Codes: F16H 61/66272 characterised by means for controlling the torque transmitting capability of the gearing
• CPC Class Codes: F16H 63/46 Signals to a clutch outside the gearbox

Abstract

The invention is directed to a method for controlling the operation of a clutch (19) which coacts with an automatic transmission stage (17). A variator controller (16) is assigned to the automatic transmission stage (17) and a contact-force control (18) is assigned to the clutch (19). Depending upon the detected and classifiable drive situations, first and second torque/contact-force reserves (13, 44) are determined which are supplied to an input quantity M_E (22) of the variator controller (16) and to the contact-force control (18) for the clutch (19). The output signals (20, 21) of the variator controller (16) and the contact-force control (18) influence the operation of the automatic transmission stage (17) and the clutch (19).

Claims

1. A method for controlling the operation of a clutch coacting with an automatic transmission stage, the method comprising the steps of:

assigning a variator controller to said automatic transmission stage and a contact-force control to said clutch;

determining first and second torque/contact-force reserves in dependence upon recognized and classifiable driving situations; and

,

supplying said first torque/contact-force reserve and an input quantity (M_E) to said contact-force control and said second torque/contact-force reserve and said input quantity (M_E) to said variator controller and forming respective output signals to influence the operation of said automatic transmission stage and said clutch.

2. The method of claim 1, wherein said contact-force control for said clutch is a slip controller.

3. The method of claim 1, wherein said input quantity (M_E) is a torque signal representing the torque to be transmitted by said automatic transmission stage and is essentially generated by an internal combustion engine and, if required, is increased or decreased by additional stages or consumers present between said internal combustion engine and a drive shaft of said automatic transmission stage.

4. The method of claim 1, comprising the further step of supplying said torque/contact-force reserve to said input quantity of said variator controller at a first summation point.

5. The method of claim 1, comprising the further step of supplying the torque/contact-force reserve to said input quantity of said contact-force control at a second summation point.

6. The method of claim 4, wherein the supply of said torque/contact-force reserves to said summation points takes place simultaneously.

7. The method of claim 1, wherein the output signals of the variator controller and contact-force control, respectively, represent respective contact forces (F_S, F_P;

F_K) which act on transmitting elements of said automatic transmission stage and parts of said clutch.

8. The method of claim 1, wherein the positions (P, D, R, N;

4, 3, 2,

     1) of the selection lever of the automatic transmission are included in the determination and classification of the driving situation.

9. The method of claim 1, wherein the positions (4AT, N, 4LO, 2AT) of said selection lever of said automatic transmission in the mode “

off-road travel”

are included in the recognition and classification of the driving situation.

10. The method of claim 1, wherein the chassis damping stages (I, II, III, IV) of a hydraulically or pneumatically charged suspension system of a motor vehicle are considered in the detection and classification of the driving situation.

11. The method of claim 1, wherein the quantities (n₁, n₂, n₃, n₄;

ω

, n_MOT, v_F, M_MOT), which influence the driving dynamic, are considered in the detection and classification of the driving situation.

12. The method of claim 1, wherein clutch quantities and transmission quantities (n_G1, n_G2;

U_G, a₁, a₂) are considered in the detection and classification of the driving situation.

13. The method of claim 1, wherein the accelerator pedal signals (h₁, h₂) are considered in the detection and classification of the driving situation of the motor vehicle.

14. The method of claim 7, characterized in that the quantities (P, D, R, N;

4, 3, 2, 1;

4AT, N, 4LO, 2AT;

I, II, III, IV;

n₁, n₂, n₃, n₄;

ω

, n_MOT, v_F;

n_G1, n_G2;

M_MOT, u_G, a₁, a₂;

h₁, h₂), which characterize the driving situation, are supplied to the torque/contact-force reserve means via a central bus system.

15. The method of claim 14, characterized in that the quantities (P, D, R, N;

4, 3, 2, 1;

4AT, N, 4LO, 2AT;

I, II, III, IV;

n₁, n₂, n₃, n₄;

ω

, n_MOT, v_F;

n_G1, n_G2;

M_MOT, u_G, a₁, a₂;

h₁, h₂), which characterize the driving situation, are supplied to the contact-force control as input quantities.

16. The method of claim 1, wherein operating parameters (n_mot, M_MOT, S_MOT) of the internal combustion engine are considered in the detection and classification of the driving situation.

17. The method of claim 2, comprising the further step of considering at least one of the following signals:

(a) the engine torque (M_MOT) which is determined by the engine control;

(b) the engine rpm (m_MOT) and quantities derived therefrom;

(c) the transmission rpms (n_G1, n_G2); and

,

(d) clutch signals (a₁, a₂);

for determining an input quantity (M_E) representing an input torque.