Electronic control apparatus for vehicle and diagnosing method thereof

• US 7,765,041 B2
• Filed: 01/19/2007
• Issued: 07/27/2010
• Est. Priority Date: 01/20/2006
• Status: Active Grant

• Current Assignee: Hitachi Astemo Ltd. (Hitachi, Ltd.)
• Original Assignee: Hitachi, Ltd.
• Inventors: Kubota, Mitsuhiko, Tatsumi, Motoki, Abe, Kazuhiko
• Primary Examiner(s): To; Tuan C
• Application Number:
  US11/655,269
• Publication Number:
  US 20070192001A1
• Time in Patent Office: 1,285 Days
• Field of Search: 701/29, 701/33, 701/34, 123/396, 123/399, 123/683, 123/188.1, 123/295, 123/436, 370/235, 370/241, 370/242, 477/7
• US Class Current: 701/29
• CPC Class Codes: B60W 50/04 Monitoring the functioning of the control system
• CPC Class Codes: F01L 1/34 characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift
• CPC Class Codes: F01L 13/0026 by means of an eccentric
• CPC Class Codes: F01L 2001/0537 Double overhead camshafts [DOHC]
• CPC Class Codes: F01L 2013/0073 with an oscillating cam acting on the valve of the "Delphi" type
• CPC Class Codes: F01L 2800/00 Methods of operation using a variable valve timing mechanism
• CPC Class Codes: F01L 2800/12 Fail safe operation
• CPC Class Codes: F01L 2820/032 Electric motors
• 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: F02D 41/26 using computer, e.g. microprocessor

Abstract

An electronic control apparatus for a vehicle having an engine control unit 114 controlling an electronically-controlled throttle of an engine and a valve control unit 141 controlling a variable lift mechanism 112 that varies a lift amount of an intake valve are provided. Information of a target lift amount and an actual lift amount is transmitted/received between these control units. Each of the control units diagnoses a state of data transmission from the other control unit, transmits the diagnosis result to the other control unit and, when the diagnosis result of itself and/or the diagnosis result of the other control unit shows an abnormal state, moves to the mode of a fail-safe operation.

Claims

1. An electronic control apparatus for a vehicle, comprising:

a first control unit for controlling an electronically-controlled throttle of an engine mounted on a vehicle;

a second control unit for controlling a variable valve mechanism that makes an open characteristic of an intake valve of the engine variable; and

a communication circuit that provides a connection for communication between the first and the second control units,

wherein the first control unit is configured to transmit a target value of the open characteristic of the intake valve to the second control unit,

wherein the second control unit is configured to transmit a detection value of the open characteristic of the intake valve to the first control unit,

wherein each of the first and the second control units is configured to diagnose a data reception abnormality, transmit a diagnosis result, and diagnose an abnormality in the communication circuit on a basis of the diagnosis result of the respective control unit and a diagnosis result of the other control unit,

wherein, when the abnormality in the communication circuit is determined, the second control unit is configured to control the variable valve mechanism to bring the open characteristic of the intake valve into a predetermined open characteristic, and

wherein, when the first control unit determines an occurrence of the abnormality in the communication circuit, the first control unit is configured to estimate that the open characteristic of the intake valve has become the predetermined open characteristic, to control the electronically-controlled throttle such that a target intake air amount in the predetermined open characteristic is obtained.

2. The electronic control apparatus for the vehicle according to claim 1, wherein the variable valve mechanism comprises a mechanism for continuously varying a lift amount and an operation angle of the intake valve.

3. An electronic control apparatus for a vehicle, comprising:

a first control unit for controlling an electronically-controlled throttle of an engine mounted on a vehicle;

a second control unit for controlling a variable valve mechanism that makes an open characteristic of an intake valve of the engine variable; and

a communication circuit that provides a connection for communication between the first and the second control units,

wherein the first control unit is configured to transmit a target value of the open characteristic of the intake valve to the second control unit,

wherein the second control unit is configured to transmit a detection value of the open characteristic of the intake valve to the first control unit,

wherein each of the first and second control units is configured to diagnose a data reception abnormality, transmit a diagnosis result, and distinctively determine a degree of an abnormality in the communication circuit as a minor abnormality or a serious abnormality on a basis of the diagnosis result of the respective control unit and a diagnosis result of the other control unit;

wherein, when the minor abnormality is determined, the second control unit is configured to control the variable valve mechanism to bring the open characteristic of the intake valve into a predetermined open characteristic,

wherein, when the minor abnormality is determined, the first control unit is configured to estimate that the open characteristic of the intake valve has become the predetermined open characteristic to control the electronically-controlled throttle such that a target intake air amount in the predetermined open characteristic is obtained,

wherein, when the serious abnormality is determined, the second control unit is configured to control the variable valve mechanism to an off state, and

wherein, when the serious abnormality is determined, the first control unit is configured to control the variable valve mechanism to the off state, to thereby control the electronically-controlled throttle such that a target air-fuel ratio in the off state of the variable valve mechanism is obtained.

4. The electronic control apparatus for the vehicle according to claim 3, wherein the variable valve mechanism comprises a mechanism for continuously varying a lift amount and an operation angle of the intake valve.

5. An electronic control apparatus for a vehicle, comprising:

a first control means for controlling an electronically-controlled throttle of an engine mounted on a vehicle;

a second control means for controlling a variable valve mechanism that makes an open characteristic of an intake valve of the engine variable; and

a communication circuit that provides a connection for communication between the first and the second control means, and

wherein the first control means is configured to transmit a target value of the open characteristic of the intake valve to the second control means,

wherein the second control means is configured to transmit a detection value of the open characteristic of the intake valve to the first control means,

wherein each of the first and the second control means is configured to diagnose a data reception abnormality, transmit a diagnosis result, and diagnose an abnormality in the communication circuit on a basis of the diagnosis result of the respective control means and a diagnosis result of the other control means,

wherein, when the abnormality in the communication circuit is determined, the second control means is configured to control the variable valve mechanism to bring the open characteristic of the intake valve into a predetermined open characteristic, and

wherein, when the first control means determines an occurrence of the abnormality in the communication circuit, the first control means is configured to estimate that the open characteristic of the intake valve has become the predetermined open characteristic, to control the electronically-controlled throttle such that a target intake air amount in the predetermined open characteristic is obtained.

6. An electronic control apparatus for a vehicle, comprising:

a first control means for controlling an electronically-controlled throttle of an engine mounted on a vehicle;

a second control means for controlling a variable valve mechanism that makes an open characteristic of an intake valve of the engine variable; and

a communication circuit that provides a connection for communication between the first and the second control means, and

wherein the first control means is configured to transmit a target value of the open characteristic of the intake valve to the second control means,

wherein the second control means is configured to transmit a detection value of the open characteristic of the intake valve to the first control means,

wherein each of the first and the second control means is configured to diagnose a data reception abnormality, transmit a diagnosis result, and distinctively determine a degree of an abnormality in the communication circuit as a minor abnormality or a serious abnormality on a basis of the diagnosis result of the respective control means and a diagnosis result of the other control means,

wherein, when the minor abnormality is determined, the second control means is configured to control the variable valve mechanism to bring the open characteristic of the intake valve into a predetermined open characteristic,

wherein, when the minor abnormality is determined, the first control means is configured to estimate that the open characteristic of the intake valve has become the predetermined open characteristic to control the electronically-controlled throttle such that a target intake air amount in the predetermined open characteristic is obtained,

wherein, when the serious abnormality is determined, the second control means is configured to control the variable valve mechanism to an off state, and

wherein, when the serious abnormality is determined, the first control means is configured to control the variable valve mechanism to the off state, to thereby control the electronically-controlled throttle such that a target air-fuel ratio in the off state of the variable valve mechanism is obtained.