Method and device for controlling a multicylinder internal combustion engine

• US 6,941,930 B2
• Filed: 01/30/2001
• Issued: 09/13/2005
• Est. Priority Date: 02/25/2000
• Status: Expired due to Fees

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Uhl, Stephan
• Primary Examiner(s): MOHANTY, BIBHU R
• Application Number:
  US10/204,761
• Publication Number:
  US 20030159677A1
• Time in Patent Office: 1,687 Days
• Field of Search: 123/406.23, 123/406.12, 123/352, 123/436, 123/439, 540/439
• US Class Current: 123/406.23
• CPC Class Codes: F02D 2041/1409 using at least a proportional, integral or derivative controller
• CPC Class Codes: F02D 2041/1422 Variable gain or coefficients
• CPC Class Codes: F02D 2200/1015 Engines misfires
• CPC Class Codes: F02D 41/1498 measuring engine roughness
• CPC Class Codes: F02D 41/22 Safety or indicating devices for abnormal conditions in air/fuel ratio feedback systems F02D41/1495, in electric control linkage F02D11/107, in purge control systems F02M25/0809
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

In a method for controlling a multicylinder internal combustion engine, where a cylinder-equalization control is performed to adjust cylinder-specific torque contributions to the overall torque of the internal combustion engine, a functioning monitoring is performed for the cylinder-equalization control, and, in response to disturbances in the area of the cylinder-equalization control, at least one error signal may be generated to indicate the existence of a disturbance.

Claims

1. A method for controlling a multicylinder internal combustion engine including a cylinder equalization control for adjusting cylinder-specific torque contributions to an overall torque of the internal combustion engine, the method comprising:

monitoring functioning of the cylinder-equalization control;

in response to a monitored disturbance in functioning of the cylinder-equalization control, generating at least one error signal indicating existence of the disturbance; and

in response to the at least one error signal, changing a control characteristic of the cylinder-equalization control.

2. The method of claim 1, further comprising:

canceling a closed-loop gain of the control characteristic.

3. The method of claim 1, further comprising:

controlling at least one combustion-related parameter of each cylinder of the internal combustion engine within a defined operating range; and

generating an error signal when the at least one combustion-related parameter of any cylinder reaches a limit of the defined operating range.

4. The method of claim 2, further comprising:

changing the control characteristic at least one additional time in response to a new error signal, subsequent to a first change in the control characteristic.

5. The method of claim 4, wherein the change of the control characteristic includes cancellation of the control loop gain.

6. The method of claim 1, wherein as a response to the at least one error signal, one of a) and b) are performed:

a) the cylinder-equalization control is switched off, and

the control characteristic is reset, and

b) as a response to the at least one error signal, the control is stopped, and

the control characteristic is retained.

7. The method of claim 6, wherein the control characeristic is reset to originally defined operating characteristics.

8. The method of claim 6, wherein the control is stopped in response to the at least one error signal following an at least one-time change in the control characteristic.

9. The method of claim 1, further comprising:

in response to the at least one error signal, emitting an external warning signal.

10. The method of claim 9, wherein the warning signal includes at least one of an optical warning display that is directly perceivable by an operator and an entry input into a memory of a diagnostic system capable of being externally queried.

11. The method of claim 9, wherein the warning signal is emitted following an at least one-time change in the control characteristic.