Starter control systems and methods for engine rockback

• US 9,022,001 B2
• Filed: 04/01/2011
• Issued: 05/05/2015
• Est. Priority Date: 02/01/2011
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Shafto, Robert Douglas
• Primary Examiner(s): Gimie, Mahmoud
• Assistant Examiner(s): HAMAOUI, DAVID E
• Application Number:
  US13/078,334
• Publication Number:
  US 20120192826A1
• Time in Patent Office: 1,495 Days
• Field of Search: 123/179.3, 123/406.58, 324/392, 701/113, 731/142.6
• US Class Current: 123/179.3
• CPC Class Codes: F02D 2250/06 Reverse rotation of engine
• CPC Class Codes: F02N 11/0814 comprising means for controlling automatic idle-start-stop
• CPC Class Codes: F02N 11/106 for stopping or interrupting starter actuation
• CPC Class Codes: F02N 2250/04 Reverse rotation of the engine

Abstract

A system for a vehicle, includes a rockback detection module and a starter disabling module. The rockback detection module receives a crankshaft position signal from a bi-directional crankshaft sensor and selectively indicates that a crankshaft of an engine is rotating in a first direction based on the crankshaft position signal. The engine rotates in a second direction that is opposite to the first direction when the engine is running. The starter disabling module disables current to a starter motor when the crankshaft is rotating in the first direction.

Claims

1. A system for a vehicle, comprising:

a rockback detection module that receives a crankshaft position signal from a bi-directional crankshaft sensor and that selectively indicates that a crankshaft of an engine is rotating in a first direction based on the crankshaft position signal,

wherein the engine rotates in a second direction that is opposite to the first direction when the engine is running; and

a starter disabling module that disables current to a starter motor when the crankshaft is rotating in the first direction and that disengages the starter motor from the engine when the crankshaft is rotating in the first direction.

2. The system of claim 1 further comprising a counter module that selectively increments and decrements a counter value based on pulses in the crankshaft position signal,

wherein the rockback detection module selectively indicates that the crankshaft is rotating in the first direction based on a change in the counter value.

3. The system of claim 2 wherein the counter module increments the counter value when a first predetermined type of pulse is generated in the crankshaft position signal and decrements the counter value when a second predetermined type of pulse is generated in the crankshaft position signal,

wherein the first and second predetermined types of pulses are different, and

wherein the rockback detection module indicates that the crankshaft is rotating in the first direction when the counter value decreases.

4. The system of claim 2 wherein the rockback detection module selectively indicates that the crankshaft is not rotating in the first direction when at least one of the counter value is constant for a predetermined period and the counter value increases.

5. The system of claim 4 wherein the starter disabling module enables application of current to the starter motor when the crankshaft is not rotating in the first direction.

6. The system of claim 1 further comprising an engine speed determination module that generates an engine speed based on pulses in the crankshaft position signal,

wherein the rockback detection module selectively indicates that the crankshaft is rotating in the first direction based on the engine speed.

7. The system of claim 6 wherein the rockback detection module indicates that the crankshaft is rotating in the first direction when the engine speed is less than zero.

8. The system of claim 6 wherein the engine speed determination module generates the engine speed based on a period between two pulses in the crankshaft position signal, a rotational distance between teeth corresponding to the two pulses, and shapes of the two pulses.

9. The system of claim 6 wherein the rockback detection module selectively indicates that the crankshaft is not rotating in the first direction when the engine speed is one of zero and positive.

10. The system of claim 9 wherein the starter disabling module enables application of current to the starter motor when the crankshaft is not rotating in the first direction.

11. The system of claim 1 further comprising a one-way clutch that, when the starter motor is engaged with the engine, couples the starter motor with the engine when a speed of the starter motor is greater than an engine speed and that de-couples the starter motor from the engine when the engine speed is greater than the speed of the starter motor.

12. A method for a vehicle, comprising:

receiving a crankshaft position signal from a bi-directional crankshaft sensor;

selectively indicating that a crankshaft of an engine is rotating in a first direction based on the crankshaft position signal,

wherein the engine rotates in a second direction that is opposite to the first direction when the engine is running;

disabling current to a starter motor when the crankshaft is rotating in the first direction; and

disengaging the starter motor from the engine when the crankshaft is rotating in the first direction.

13. The method of claim 12 further comprising:

selectively incrementing and decrementing a counter value based on pulses in the crankshaft position signal; and

selectively indicating that the crankshaft is rotating in the first direction based on a change in the counter value.

14. The method of claim 13 further comprising:

incrementing the counter value when a first predetermined type of pulse is generated in the crankshaft position signal;

decrementing the counter value when a second predetermined type of pulse is generated in the crankshaft position signal,

wherein the first and second predetermined types of pulses are different; and

indicating that the crankshaft is rotating in the first direction when the counter value decreases.

15. The method of claim 13 further comprising selectively indicating that the crankshaft is not rotating in the first direction when at least one of the counter value is constant for a predetermined period and the counter value increases.

16. The method of claim 15 further comprising enabling application of current to the starter motor when the crankshaft is not rotating in the first direction.

17. The method of claim 12 further comprising:

generating an engine speed based on pulses in the crankshaft position signal; and

selectively indicating that the crankshaft is rotating in the first direction based on the engine speed.

18. The method of claim 17 further comprising indicating that the crankshaft is rotating in the first direction when the engine speed is less than zero.

19. The method of claim 17 further comprising generating the engine speed based on a period between two pulses in the crankshaft position signal, a rotational distance between teeth corresponding to the two pulses, and shapes of the two pulses.

20. The method of claim 17 further comprising selectively indicating that the crankshaft is not rotating in the first direction when the engine speed is one of zero and positive.

21. The method of claim 20 further comprising enabling application of current to the starter motor when the crankshaft is not rotating in the first direction.