SYSTEM FOR RESTARTING INTERNAL COMBUSTION ENGINE WHEN ENGINE RESTART CONDITION IS MET

• US 20110056450A1
• Filed: 09/07/2010
• Published: 03/10/2011
• Est. Priority Date: 09/04/2009
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: NOTANI, Hideya
• Granted Patent: US 8,671,903 B2
• Time in Patent Office: Days
• US Class Current: 123/179.4
• CPC Class Codes: F02N 11/0844 with means for restarting the engine directly after an engine stop request, e.g. caused by change of driver mind
• CPC Class Codes: F02N 11/0855 during engine shutdown or after engine stop before start command, e.g. pre-engagement of pinion
• CPC Class Codes: F02N 2200/022 Engine speed
• CPC Class Codes: F02N 2200/048 Information about pinion speed, both translational or rotational speed

Abstract

In a system, a pinion shift unit starts shift of a pinion to a ring gear for engagement therebetween during an internal combustion engine coasting in a forward direction after an automatic stop of the internal combustion engine. An engagement determining unit determines whether the pinion and the ring gear have any one of first and second positional relationships therebetween. The first positional relationship represents that the pinion is at least partly engaged with the ring gear. The second positional relationship represents that the pinion is in abutment with the ring gear. When an engine restart condition is met before it is determined that the pinion and the ring gear have any one of first and second positional relationships therebetween after the start of the shift of the pinion to the ring gear, a rotation adjusting unit adjusts a start timing of rotation of the pinion.

Claims

1. A system for causing a starter with a pinion to crank an internal combustion engine with an output shaft to which a ring gear is coupled in response to when an engine restart condition is met after an automatic stop of the internal combustion engine, the system comprising:

a pinion shift unit configured to start shift of the pinion to the ring gear for engagement of the pinion with the ring gear during the internal combustion engine coasting in a forward direction after the automatic stop of the internal combustion engine;

an engagement determining unit configured to determine whether the pinion and the ring gear have any one of first and second positional relationships therebetween, the first positional relationship representing that the pinion is at least partly engaged with the ring gear, the second positional relationship representing that the pinion is in abutment with the ring gear; and

a rotation adjusting unit configured to, when the engine restart condition is met before it is determined that the pinion and the ring gear have any one of first and second positional relationships therebetween by the engagement determining unit after the start of the shift of the pinion to the ring gear, adjust a start timing of rotation of the pinion.

2. The system according to claim 1, wherein the rotation adjusting unit is configured to, when the engine restart condition is met before it is determined that the pinion and the ring gear have any one of first and second positional relationships therebetween by the engagement determining unit after the start of the shift of the pinion to the ring gear, wait for a start of rotation of the pinion until it is determined that the pinion and the ring gear have any one of the first and second positional relationships therebetween by the engagement determining unit, and thereafter start rotation of the pinion.

3. The system according to claim 2, further comprising:

a period setting unit configured to set a rotation disable period when it is determined that, by the engagement determining unit, the pinion and the ring gear have any one of the first and second positional relationships therebetween during rotation of the output shaft of the internal combustion engine in a reverse direction, the rotation adjusting unit disabling rotation of the pinion within the rotation disable period,

wherein the rotation adjusting unit is configured to, when the rotation disable period is set by the period setting unit, wait for a lapse of the rotation disable period, and thereafter start rotation of the pinion.

4. The system according to claim 3, wherein the engagement determining unit comprises a determining unit configured to determine, based on at least one of a speed of the internal combustion engine and a parameter associated with the speed of the internal combustion engine, whether the pinion and the ring gear have any one of the first and second positional relationships therebetween during rotation of the output shaft of the internal combustion engine in the reverse direction, and the period setting unit is configured to set the rotation disable period when it is determined that, by the determining unit, the pinion and the ring gear have any one of the first and second positional relationships therebetween during rotation of the output shaft of the internal combustion engine in the reverse direction.

5. The system according to claim 4, wherein the determining unit is configured to determine, based on a reduction rate of the speed of the internal combustion engine, whether the pinion and the ring gear have any one of the first and second positional relationships therebetween during rotation of the output shaft of the internal combustion engine in the reverse direction.

6. The system according to claim 2, wherein the rotation adjusting unit is configured to make earlier the start timing of rotation of the pinion when a reduction rate of a speed of the internal combustion engine after the automatic stop of the internal combustion engine is greater than a first preset threshold.

7. The system according to claim 1, wherein the first positional relationship represents that the pinion is completely engaged with the ring gear, further comprising a required-time determining unit configured to determine whether an engagement required time is equal to or less than a second preset threshold, the engagement required time being a time required from the start of the shift of the pinion to the ring gear to a completion of an engagement of the pinion with the ring gear,

wherein the rotation adjusting unit is configured to, when the engine restart condition is met before it is determined that the pinion and the ring gear have the first positional relationship therebetween by the engagement determining unit after the start of the shift of the pinion to the ring gear, and when it is determined that the engagement required time is equal to or less than the second preset threshold, start rotation of the pinion without waiting for the determination that the pinion and the ring gear have the first positional relationship therebetween.

8. The system according to claim 7, wherein the rotation adjusting unit is configured to, when the engine restart condition is met before the pinion is in abutment with the ring gear, start rotation of the pinion at a timing when the pinion is shifted to be in abutment with the ring gear.

9. The system according to claim 7, wherein the required-time determining unit is configured to determine whether the engagement required time is equal to or less than the second preset threshold based on a parameter associated with a temperature of the internal combustion engine.

10. The system according to claim 7, wherein the required-time determining unit is configured to determine whether the engagement required time is equal to or less than the second preset threshold based on a number of starts of the internal combustion engine by the starter.