Method for determining a measuring point of a hybrid decoupler of a hybrid vehicle

Abstract

A method for determining a measuring point of a hybrid decoupler of a hybrid vehicle, which is operated by a hydrostatic clutch actuator, with the hybrid decoupler coupling or decoupling an internal combustion engine and an electro-traction drive. The measuring point is determined by a slow operation of the hybrid decoupler, starting from a position of the hybrid decoupler which it assumes in the idle state, when a defined increase in torque is detected at the electro-traction drive. In the method, the term for measuring adaption is considerably shortened, and the measuring point is adapted at a running internal combustion engine and a stationary electro-traction drive.

Claims

1. A method for determining a modified measuring point of a hybrid decoupler of a hybrid vehicle, which is operated by a hydrostatic clutch actuator, said hybrid decoupler coupling or decoupling an internal combustion engine and an electro-traction drive, the method comprising: determining an initial measuring point by slow operation of the hybrid decoupler, starting from a position of the hybrid decoupler in an idle state, detecting a defined increase in torque at the electro-traction drive, and then adapting the initial measuring point to an adapted measuring point while the internal combustion engine is running and the electro-traction drive is stopped.

2. The method according to claim 1, wherein the electro-traction drive is speed-controlled.

3. The method according to claim 1, wherein the internal combustion engine is operated at an idling speed.

4. The method according to claim 1, wherein during the adaption of the initial measuring point, the internal combustion engine is decoupled from a drivetrain.

5. The method according to claim 1, wherein the initial measuring point is adapted during operation of the hybrid vehicle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention allows numerous embodiments. One of them shall be explained in greater detail based on the figures shown in the drawing.

(2) In the drawings:

(3) FIG. 1 is a principle illustration of a hybrid drive of a hybrid vehicle.

DETAILED DESCRIPTION FO THE PREFERRED EMBODIMENTS

(4) FIG. 1 shows a principle illustration of a drivetrain 1 of a hybrid vehicle. This drivetrain 1 comprises an internal combustion engine 2 and an electric motor 3. Between the internal combustion engine 2 and the electric motor 3, directly downstream the internal combustion engine 2, a hybrid decoupler 4 is arranged. The internal combustion engine 2 and the hybrid decoupler 4 are connected to each other via a crankshaft 5. The electric motor 3 comprises a rotor 6, which can be rotated, and a stationary stator 7. The driven shaft 8 of the hybrid decoupler 4 is connected to the transmission 9, which comprises another coupling element, not shown, for example a second clutch or a torque converter, arranged between the electric motor 3 and the transmission 9. The transmission 9 transmits the torque generated by the internal combustion engine 2 and/or the electric motor 3 to the driving wheels 10 of the hybrid vehicle. Here, the hybrid decoupler 4 and the transmission 9 form a transmission system 11, which is controlled by a hydrostatic clutch actuator 12, used in combination with the hybrid decoupler 4, which is closed in the idle state. The hybrid decoupler 4 is operated by the hydrostatic clutch actuator 12 over a hydrostatic stroke. The master piston in the master cylinder, which is arranged in the hydrostatic clutch actuator, is adjusted by the electric motor. This way, a slave piston in the slave cylinder is actuated via hydraulic fluid in the hydrostatic stroke. The slave piston of the slave cylinder acts here upon the tips of the lever springs of a flat spring, which then lifts off a clutch disk, upon actuation of a clutch plate, and this way the transfer of torque is interrupted by the hybrid decoupler 4. In the idle state, the pre-stressed lever spring closes the hybrid decoupler 4.

(5) The measuring point is of particular importance for controlling the hybrid decoupler 4 and thus it is determined during the initial start of operation of the hybrid vehicle and adapted during the drive operation of the hybrid vehicle. The adaption of the measuring point occurs during a rotating internal combustion engine 2 when the hybrid vehicle is in operation. The internal combustion engine 2 runs here in the idling mode. By speed control the electric motor 3 of the electro-traction drive is kept in the stationary state. During the adaption of the measuring point the hybrid decoupler 4 is opened and is slowly moved into the closed state. At the point of time at which the decoupler 4 begins to transmit a torque, the electric motor 3 of the electro-traction drive is slightly entrained. Due to the speed control connected to the electro-traction drive the torque of the electric motor 3 of the electro-traction drive increases. When a defined increase in torque is given, the present measuring point is detected. Due to the fact that the electric motor 3 of the electro-traction drive is not rotating at the start of the measuring point detection process, any drastic reductions in rotation are reliably prevented. During the adaption process of the measuring point it must be ensured that the drive train is decoupled from the internal combustion engine.

LIST OF REFERENCE CHARACTERS

(6) 1 Drivetrain

(7) 2 Internal combustion engine

(8) 3 Electric motor

(9) 4 Hybrid decoupler

(10) 5 Crankshaft

(11) 6 Rotor

(12) 7 Stator

(13) 8 Driven shaft

(14) 9 Transmission

(15) 10 Driving wheels

(16) 11 Transmission system

(17) 12 Clutch actuator