Impulse start in a hybrid drivetrain

Patent metadata

Field	Value
Publication number	US-11359593-B2
Application number	US-202016797935-A
Country	US
Kind code	B2
Filing date	Feb 21, 2020
Priority date	Aug 23, 2017
Publication date	Jun 14, 2022
Grant date	Jun 14, 2022

Abstract

A hybrid drive device includes an internal combustion engine, an electric machine and an impulse start module which comprises two clutches and a flywheel mass. A method for operating the hybrid device includes opening the first clutch of the impulse-start module and establishing a start-up requirement for the internal-combustion engine. The method also includes closing the first clutch with the second clutch in an open or closed position for a start of the internal-combustion engine.

First claim

What is claimed is:

1. A method for operating a hybrid-drive device of a motor vehicle, wherein the hybrid-drive device comprises: an internal-combustion engine, an electric machine, and an impulse-start module, wherein the impulse-start module comprises a first clutch, a second clutch, and a centrifugal mass coupled to the internal-combustion engine solely via the first clutch and to the electric machine solely via the second clutch, the method comprising:
opening the first clutch;
establishing a start-up requirement for the internal-combustion engine;
closing the first clutch, so as to couple the centrifugal mass to the internal-combustion engine, while opening the second clutch to an open position and thereby decoupling the centrifugal mass from the electric machine, when the start-up requirement is a first start-up requirement, and while maintaining the second clutch in a closed position, coupling the centrifugal mass to the electric machine, when the start-up requirement is a second start-up requirement, so as to start the internal-combustion engine in accordance with the start-up requirement;
selecting a speed of the centrifugal mass such that, during the start of the internal-combustion engine, the speed of the centrifugal mass lies above an idling speed of the internal-combustion engine prior to closing the first clutch; and
shifting the electric machine at least one gear higher after opening the second clutch and prior to closing the first clutch.

2. The method according to claim 1 , wherein the start of the internal-combustion engine is performed with the aid of a reciprocal actuation of the first clutch and the second clutch of the impulse-start module.

3. The method according to claim 1 , wherein the start of the internal-combustion engine is executed as an initial start.

4. The method according to claim 2 , wherein the start of the internal-combustion engine is executed as an initial start.

5. The method according to claim 1 , wherein the impulse-start module starts the internal-combustion engine during electric starting, whereby the centrifugal mass of the impulse-start module is coupled with the electric machine by the second clutch in the closed position.

6. The method according to claim 2 , wherein the impulse-start module starts the internal-combustion engine during electric starting, whereby the centrifugal mass of the impulse-start module is coupled with the electric machine by the second clutch in the closed position.

7. The method according to claim 1 , wherein the impulse-start module starts the internal-combustion engine during engine-off coasting or during electric driving.

8. The method according to claim 2 , wherein the impulse-start module starts the internal-combustion engine during engine-off coasting or during electric driving.

Assignees

• Bayerische Motoren Werke Ag

Inventors

• Hoess Bernhard
• Jung Thomas
• Kobler Sebastian

Classifications

• Y02T10/62

  Hybrid vehicles · CPC title

• B60W20/10

  Controlling the power contribution of each of the prime movers to meet required power demand · CPC title

• B60W2510/0225

  Clutch actuator position · CPC title

• F02N2300/2002

  using different starting modes, methods, or actuators depending on circumstances, e.g. engine temperature or component wear · CPC title

• B60W2710/082

  Speed change rate · CPC title