Method of examining operation of electronic control system for internal combustion engines

• US 4,887,215 A
• Filed: 06/25/1986
• Issued: 12/12/1989
• Est. Priority Date: 06/25/1985
• Status: Expired due to Fees

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company), OKI Electric Industry Company Limited
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Kimura, Yutaka, Juman, Shinji, Kumagai, Chiaki, Mitomo, Haruhito
• Primary Examiner(s): Lall, Parshotam S.
• Assistant Examiner(s): Ramirez, Ellis B.
• Application Number:
  US06/878,571
• Time in Patent Office: 1,266 Days
• Field of Search: 364/431.04, 364/431.11, 364/571.04, 364/571.07, 73/117.3, 73/116, 377/29, 377/30, 377/39, 371/8, 371/20, 371/25, 371/16, 123/478, 123/414, 123/416, 123/417, 123/428, 123/359
• US Class Current: 701/102
• CPC Class Codes: F02D 41/009 using means for generating position or synchronisation signals
• CPC Class Codes: F02P 17/00 Testing of ignition installations, e.g. in combination with adjusting testing fuel injection apparatus F02M65/00; testing ignition installations in general F23Q23/00; Testing of ignition timing in compression-ignition engines
• CPC Class Codes: F02P 7/0675 with variable reluctance, e.g. depending on the shape of a tooth
• CPC Class Codes: G01R 31/006 on road vehicles, e.g. automobiles or trucks testing of ignition installations peculiar to internal combustion engines F02P17/00
• CPC Class Codes: G01R 31/007 using microprocessors or computers

Abstract

A method of examining operation of an electronic control system for an internal combustion engine having a crankshaft, the control system having a mechanism for generating pulse signals indicative of angular position of the crankshaft and a processing circuit for evaluating the indicative pulse signals so as to output pulse signals for controlling an engine operation-related factor. The mechanism generates each indicative pulse signal at a time when the crankshaft is at one of predetermined angular positions. The processing circuit outputs each control pulse signal when the crankshaft is at a desired angular position. According to the method, the indicative pulse signals are continuously counted so as to generate a succession of counted numbers, each counted number representing the number of the indicative pulse signals generated during a time from an occurrence of one the control pulse signal to an occurrence of next the control pulse signal. Then, whether or not the succession of counted numbers meets one of predetermined conditions is tested, and results of the testing are evaluated so as to examine operation of the control system.

Claims

1. A method of examining operation of an electronic control system for an internal combustion engine having a crankshaft, said electronic control system having a mechanism for generating indicative pulse signals indicative of angular position of said crankshaft and means for evaluating said indicative pulse signals so as to output control pulse signals for controlling an engine operation-related factor, said mechanism for generating indicative pulse signals generating each said indicative pulse signal at a time when said crankshaft is at one of predetermined angular positions, said means for evaluating outputting each said control pulse signal when said crankshaft is at a desired angular position, said method comprising the steps of:

counting continuously said indicative pulse signals so as to generate a succession of counted numbers, each said counted number representing the number of said indicative pulse signals continuously generated during a time from an occurrence of one said control pulse signal to an occurrence of next said control pulse signal, each said counted number varying dependent upon operating conditions of said engine, and varying the timing of the outputs of said control pulse signal by said means for evaluating according to said varying counted numbers;

testing whether or not said succession of counted numbers meets one of predetermined conditions by comparing a combination of the latest counted numbers with predetermined combination of numbers; and

evaluating results of said testing so as to examine operation of said control system.

2. A method according to claim 1, wherein said engine operation-related factor controlled by said control system is ignition timing, said control pulse signals are ignition command signals for said ignition timing, and said evaluating step includes the step of preventing said ignition command signals in accordance with said testing.

3. A method according to claim 1, wherein said testing step is the step of comparing a combination of the latest three of said counted numbers with predetermined combinations of numbers.

4. A method of examining operation of an electronic control system for an internal combustion engine having a crankshaft, said electronic control system having a mechanism for generating indicative pulse signals indicative of angular position of said crankshaft and means for evaluating said indicative pulse signals so as to output conrol pulse signals for controlling an engine operation-related factor, said mechanism for generating indicative pulse signals generating each said indicative pulse signal at a time when said crankshaft is at one of a plurality of predetermined angular positions, said means for evaluating outputting each said control pulse signal when said crankshaft is at a desired angular position, said method comprising the steps of:

detecting a reference crank angle position;

calculating a time Te required for the crankshaft to make its last revolution;

storing the calculated time Te;

determining present rotational speed of the engine Ne and which one of several predetermined engine speed ranges the present rotational speed Ne of the engine falls within;

setting flags according to the speed range in which Ne falls;

calculating and storing a suitable angle of advance θ

ig;

calculating and storing a continuous current supply time Ton during which current is continuously supplied to an ignition coil; and

calculating current supply starting timing data Tcg and ignition timing data Tig based on the angle of advance θ

ig and the continuous current supply time Ton.