Stop and start control apparatus of internal combustion engine

• US 6,807,934 B2
• Filed: 01/23/2004
• Issued: 10/26/2004
• Est. Priority Date: 02/04/2003
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Kataoka, Kenji, Kusaka, Yasushi
• Primary Examiner(s): Gimie, Mahmoud
• Assistant Examiner(s): Castro, Arnold
• Application Number:
  US10/762,539
• Publication Number:
  US 20040149247A1
• Time in Patent Office: 277 Days
• Field of Search: 123/179.3, 123/179.4, 123/179.5, 123/179.16, 123/179.28, 180/65.2, 180/65.3, 180/65.4, 318/445, 290/31, 290/38.R, 290/38.B
• US Class Current: 123/179.4
• CPC Class Codes: F02D 2041/0095 Synchronisation of the cylinders during engine shutdown
• CPC Class Codes: F02N 11/006 using a plurality of electric motors
• CPC Class Codes: F02N 11/04 the motors being associated with current generators
• CPC Class Codes: F02N 11/0814 comprising means for controlling automatic idle-start-stop
• CPC Class Codes: F02N 19/005 Aiding engine start by starting from a predetermined position, e.g. pre-positioning or reverse rotation
• CPC Class Codes: F02N 2019/007 using inertial reverse rotation
• CPC Class Codes: F02N 2200/021 Engine crank angle
• CPC Class Codes: F02N 2300/104 Control of the starter motor torque
• CPC Class Codes: F02N 2300/2002 using different starting modes, methods, or actuators depending on circumstances, e.g. engine temperature or component wear
• CPC Class Codes: F02N 99/006 Providing a combustible mixture inside the cylinder
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

When a crank angle is controlled to stop at an optimal crank angle stop position by an engine automatic stop control, such as idling stop, or when the crank angle stop position can be estimated with high accuracy, the automatic engine restart is performed by a motor generator serving as an electric motor or an electric generator, at the next time of restarting of the engine. On the other hand, when the crank angle is not controlled to stop at the optimal crank angle stop position, when the crank angle stop position cannot be estimated with the high accuracy, or when the crank angle stop position changes after the stop control, the engine is restarted by a DC starter having an output torque larger than that of a motor generator, at the next time of restarting of the engine.

Claims

1. A stop and start control apparatus of an internal combustion engine comprising:

a stop control unit which controls a crank angle of the internal combustion engine within a range of a predetermined crank angle at a time of stopping the internal combustion engine; and

a start control unit which starts the internal combustion engine by a cranking unit at a time of starting the internal combustion engine,

wherein the start control unit starts the internal combustion engine by different methods when there is a probability that the internal combustion engine does not stop within the range of the predetermined crank angle and when the internal combustion engine stops within the range of the predetermined crank angle.

2. The stop and start control apparatus of the internal combustion engine according to claim 1,

wherein the cranking unit is an electric motor, and

wherein the start control unit starts the internal combustion engine by applying, by the electric motor, a larger torque when there is a probability that the internal combustion engine does not stop within the range of the predetermined crank angle than when the internal combustion engine stops within the range of the predetermined crank angle.

3. The stop and start control apparatus of the internal combustion engine according to claim 1, wherein the start control unit starts the internal combustion engine by a first electric motor when the internal combustion engine stops within the range of the predetermined crank angle, and by a second electric motor different from the first electric motor when there is a probability that the internal combustion engine does not stop within the range of the predetermined crank angle.

4. The stop and start control apparatus of the internal combustion engine according to claim 3, wherein the first electric motor is a motor generator functioning as a motor and an electric generator, and wherein the second electric motor is a DC starter functioning as a motor.

5. The stop and start control apparatus of the internal combustion engine according to claim 2, wherein the start control unit starts the internal combustion engine by combusting, during an expansion stroke, a fuel supplied at the time of stopping the internal combustion engine when the internal combustion engine stops within the range of the predetermined crank angle, and wherein the start control unit starts the internal combustion engine by the electric motor when there is a probability that the internal combustion engine does not stop within the range of the predetermined crank angle.

6. The stop and start control apparatus of the internal combustion engine according to claim 1, wherein a case when there is a probability that the internal combustion engine does not stop within the range of the predetermined crank angle includes a case when an actual crank angle at the time of stopping the internal combustion engine is out of the range of the predetermined crank angle.

7. The stop and start control apparatus of the internal combustion engine according to claim 6, wherein the actual crank angle is outputted from a crank angle sensor detecting the crank angle of the internal combustion engine.

8. The stop and start control apparatus of the internal combustion engine according to claim 1, wherein a case when there is a probability that the internal combustion engine does not stop within the range of the predetermined crank angle includes a case when an estimation accuracy of an estimating processing of the crank angle at the time of stopping the internal combustion engine is smaller than a predetermined standard.

9. The stop and start control apparatus of the internal combustion engine according to claim 8, wherein the estimating processing estimates the crank angle based on an output from the crank angle sensor of the internal combustion engine and a rotation detecting output from the electric motor functioning as the cranking unit.

10. The stop and start control apparatus of the internal combustion engine according to claim 9, wherein the estimating processing corrects the rotation detecting output from the electric motor by the output from the crank angle sensor.

11. The stop and start control apparatus of the internal combustion engine according to claim 1, wherein a case when there is a probability that the internal combustion engine does not stop within the range of the predetermined crank angle includes a case when there is a probability that the crank angle changes after the stop of the internal combustion engine.

12. The stop and start control apparatus of the internal combustion engine according to claim 11, wherein a case when there is a probability that the crank angle changes includes a case when the crank angle changes by receiving an external force after the stop of the internal combustion engine.

13. The stop and start control apparatus of the internal combustion engine according to claim 1, wherein the stop control unit automatically stops the internal combustion engine when a predetermined stop condition is satisfied, and wherein the start control unit automatically starts the internal combustion engine when a predetermined start condition is satisfied.