Engine control device

• US 20070255528A1
• Filed: 04/30/2007
• Published: 11/01/2007
• Est. Priority Date: 04/29/2006
• Status: Active Grant

• Current Assignee: Dr Ing hc F Porsche AG (Volkswagen AG)
• Original Assignee: Dr Ing hc F Porsche AG (Volkswagen AG)
• Inventors: Gruenter, Thomas, Geertz, Marko
• Granted Patent: US 7,481,103 B2
• Time in Patent Office: Days
• US Class Current: 702/183
• CPC Class Codes: F02D 11/105 characterised by the function converting demand to actuation, e.g. a map indicating relations between an accelerator pedal position and throttle valve opening or target engine torque
• CPC Class Codes: F02D 11/107 Safety-related aspects
• CPC Class Codes: G01M 15/044 by monitoring power, e.g. by operating the engine with one of the ignitions interrupted; by using acceleration tests

Abstract

An engine control device controls an engine of a motor vehicle. The engine control device predefines an admissible engine torque on the basis of a torque envelope curve in dependence on an accelerator pedal position and an engine speed. The engine control device is connected to a diagnostic device. An intervention variable, that represents an engine torque and/or an engine speed and on the basis of which the engine can be actuated for test/diagnostic purposes, can be predefined for the engine control device by the diagnostic device. When at least one test criterion is fulfilled in the engine control device and/or the diagnostic device, the torque envelope curve of the engine control device can be widened or bypassed for test/diagnostic purposes in such a way that given an unactivated accelerator pedal for a defined engine torque at the request of the diagnostic device a larger engine torque is admissible.

Claims

1. An engine controller for an engine of a motor vehicle, the engine controller comprising:

an engine control device predefining an admissible engine torque on a basis of a torque envelope curve in dependence on an accelerator pedal position and an engine speed, said engine control device having an interface for connecting to a diagnostic device, the diagnostic device predefining an intervention variable for said engine control device, the intervention variable representing at least one of an engine torque and the engine speed and on a basis of the intervention variable the engine being actuated for at least one of test purposes and diagnostic purposes, when at least one test criterion being fulfilled in at least one of said engine control device and the diagnostic device, the torque envelope curve of said engine control device can be one of widened and bypassed for one of test purposes and diagnostic purposes such that given an unactivated accelerator pedal for a defined engine torque at a request of the diagnostic device a larger engine torque is admissible than the engine torque predefined by the torque envelope curve given the unactivated accelerator pedal and a defined engine speed.

2. The engine controller according to claim 1, wherein the torque envelope curve of said engine control device can be one of widened and bypassed for one of test purposes and diagnostic purposes only if the motor vehicle is stationary.

3. The engine controller according to claim 1, wherein the torque envelope curve of said engine control device can be one of widened and bypassed for one of test purposes and diagnostic purposes for factory diagnostics at an end of a motor vehicle production system and/or in workshop diagnostic systems.

4. The engine controller according to claim 3, wherein the torque envelope curve of said engine control device can be one of widened and bypassed exclusively for one of test purposes and diagnostic purposes for the factory diagnostics at the end of the motor vehicle production system, the widening or bypassing of the torque envelope curve can be blocked automatically and irreversibly.

5. The engine controller according to claim 1, wherein fulfillment of the at least one test criteria in at least one of said engine control device and the diagnostic device can be tested as a test between said engine control device and the diagnostic device.

6. The engine controller according to claim 1, wherein for checking whether the at least one test criteria which are predetermined in said engine control device and the diagnostic device are fulfilled, the diagnostic device for said engine control device transmits at least one diagnostic message, on a basis of which it is checked whether the widening or bypassing of the torque envelope curve is admissible.

7. The engine controller according to claim 6, wherein the diagnostic message also contains, in addition to an intervention request and the intervention variable which represents at least one of the engine torque and the engine speed, a message counter and a message checksum, wherein the widening or bypassing of the torque envelope curve, is admissible only if the message counter and the message checksum fulfill predetermined test criteria.

8. The engine controller according to claim 3, wherein the torque envelope curve of said engine control device can be one of widened and bypassed exclusively for one of test purposes and diagnostic purposes for factory diagnostics at the end of the motor vehicle production system, the widening or bypassing of the torque envelope curve can be blocked automatically and irreversibly if a defined number of engine starts is exceeded.