Method and system for pre-ignition control

• US 8,627,800 B2
• Filed: 08/16/2012
• Issued: 01/14/2014
• Est. Priority Date: 12/03/2010
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Glugla, Chris Paul, Weber, Chris Richard, Rollinger, John Eric
• Primary Examiner(s): Gimie, Mahmoud
• Assistant Examiner(s): HAMAOUI, DAVID E
• Application Number:
  US13/587,829
• Publication Number:
  US 20120316762A1
• Time in Patent Office: 516 Days
• Field of Search: 123/310, 123/406.21, 123/406.29, 123/406.37, 701/111, 731/146.3
• US Class Current: 123/406.29
• CPC Class Codes: F02B 37/00 Engines characterised by provision of pumps driven at least for part of the time by exhaust
• CPC Class Codes: F02D 13/0226 changing valve lift or valve lift and timing
• CPC Class Codes: F02D 2250/14 Timing of measurement, e.g. synchronisation of measurements to the engine cycle
• CPC Class Codes: F02D 35/027 using knock sensors
• CPC Class Codes: F02P 5/152 dependent on pinking detecting or indicating knocks in internal-combustion engines G01L23/22
• CPC Class Codes: G01L 23/225 circuit arrangements therefor
• CPC Class Codes: G01M 15/12 by monitoring vibrations
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

Methods and systems are provided for identifying and differentiating knock and pre-ignition using a plurality of knock sensors distributed along an engine block. By dynamically adjusting cylinder-specific assignment of the knock sensors for knock detection and pre-ignition detection based on operating conditions of each cylinder, knock and pre-ignition is more reliably identified and distinguished.

Claims

1. A method of operating an engine including a first and a second knock sensor at different locations, comprising:

during a first condition, indicating knock in a cylinder based on one of the first and second knock sensor while indicating pre-ignition in the cylinder based on each of the first and second knock sensor; and

during a second condition, indicating knock in the cylinder based on each of the first and second knock sensor while indicating pre-ignition in the cylinder based on one of the first and second knock sensor.

2. The method of claim 1, wherein indicating knock based on one of the first and second knock sensor includes indicating knock in a first cylinder based on the first knock sensor and indicating knock in a second cylinder based on the second knock sensor.

3. The method of claim 1, wherein indicating knock based on one of the first and second knock sensor includes indicating knock in each of a first and a second cylinder based on either the first knock sensor or the second knock sensor.

4. The method of claim 1, wherein indicating pre-ignition based on one of the first and second knock sensor includes indicating pre-ignition in a first cylinder based on the first knock sensor and indicating pre-ignition in a second cylinder based on the second knock sensor.

5. The method of claim 1, wherein indicating pre-ignition based on one of the first and second knock sensor includes indicating pre-ignition in each of a first and a second cylinder based on either the first knock sensor or the second knock sensor.