Method of protection and fault detection for starter/alternator operating in the starter mode

• US 20040036296A1
• Filed: 11/26/2002
• Published: 02/26/2004
• Est. Priority Date: 06/18/2002
• Status: Active Grant

• Current Assignee: Dana Automotive Systems Group, LLC (Dana, Inc.)
• Original Assignee: Dana Corporation (Dana, Inc.)
• Inventors: Blackburn, Scott Evart, Manning, Eric Keith
• Granted Patent: US 6,800,952 B2
• Time in Patent Office: Days
• US Class Current: 290/48
• CPC Class Codes: F02N 11/04 the motors being associated with current generators
• CPC Class Codes: F02N 11/0848 with means for detecting successful engine start, e.g. to stop starter actuation
• CPC Class Codes: F02N 11/108 for diagnosis of the starter or its components
• CPC Class Codes: F02N 2200/022 Engine speed
• CPC Class Codes: F02N 2200/041 Starter speed
• CPC Class Codes: H02H 7/0816 concerning the starting sequence, e.g. limiting the number of starts per time unit, monitoring speed during starting
• CPC Class Codes: H02H 7/093 against increase beyond, or decrease below, a predetermined level of rotational speed centrifugal switches H01H35/10

Abstract

A system of preserving a starter/alternator in an I.C. engine system installation from excessive operation in the starter mode is disclosed. The system describes a method of comparing the respective rotational speeds of the starter/alternator and I.C. engine in starter mode first to each other and then, if the same, to a predetermined threshold speed. If an overspeed condition is detected, disabling the starter/alternator in starter mode. In addition, if a predetermined number of I.C. engine start sequences have occurred without successful I.C. engine operation, the starter mode is disabled for a predetermined period of time. If several start failures have been detected, the starter/alternator can be disabled until a repair of the I.C. engine fault can be made. Where the respective rotational speeds of the starter/alternator and I.C. engine differ, the system controller follows a series of logic steps to determine the fault and thereafter either notify the system controller and/or disable the starter/alternator.

Claims

1. A method of protecting a starter/alternator system for initiating I.C. engine operation from excessive operation in a starter mode, comprising the steps of:

initiating a starting sequence to start an I.C. engine,

detecting respective rotational speeds of said I.C. engine and said starter/alternator;

comparing said respective speeds and determining whether the respective speeds are the same and, if so,

comparing said detected speed with a predetermined acceptable rotational speed; and

,

disabling said starter/alternator in said starter mode when said detected speed exceeds said predetermined acceptable rotational speed.

2. A method as in claim 1, further comprising:

detecting a number of successive non-successful I.C. engine starter sequence initiations to obtain a first detected number;

comparing said first detected number to a predetermined acceptable number of non-successful I.C. engine start sequences; and

,

disabling said starter/alternator in said starter mode for a predetermined period of time when said first detected number exceeds said predetermined acceptable number of non-successful I.C. engine start sequences.

3. A method as in claim 1, wherein:

said detecting step for said I.C. engine rotational speed is accomplished using a detected rotational speed of said I.C. engine crankshaft or camshaft.

4. A method as in claim 1, wherein:

said detecting step for said I.C. engine rotational speed is accomplished using a detected rotational speed of an I.C. engine driven accessory.

5. A method of protecting a starter/alternator system for initiating I.C. engine operation from excessive operation in a starter mode, comprising the steps of:

initiating a starting sequence to start an I.C. engine,

detecting respective rotational speeds of said I.C. engine and said starter/alternator;

comparing said respective speeds and determining whether the respective speeds are the same and, if not,

determining whether said IC engine speed or said starter/alternator is rotating faster, if said IC engine speed is faster,

determining whether said starter/alternator speed is zero, and, where said starter alternator speed is zero,

disabling said starter/alternator in said starter mode, and, where said starter/alternator speed is greater than zero,

determining whether said IC is running and, if not, disabling said starter/alternator in said starter mode.

6. A method of protecting a starter/alternator system for initiating I.C. engine operation from excessive operation in a starter mode, comprising the steps of:

initiating a starting sequence to start an I.C. engine,

detecting respective rotational speeds of said I.C. engine and said starter/alternator;

comparing said respective speeds and determining whether the respective speeds are the same and, if not,

determining whether said IC engine speed or said starter/alternator is rotating faster, if said starter/alternator speed is faster,

determining whether said I.C. engine speed is zero, and, where said I.C. engine speed is zero,

disabling said starter/alternator in said starter mode, and, where said I.C. engine speed is greater than zero,

notifying a system controller of a fault relating to the starter/alternator and I.C. engine,

determining whether said IC engine is running and, if not, continuing said starter/alternator in said starter mode until a predetermined number of I.C. engine revolutions have occurred or until a predetermined number of I.C. engine start sequences have been performed and, thereafter,

disabling said starter/alternator in said starter mode.