Operation method and operation control device of internal combustion engine for vehicle that temporarily stops engine

• US 6,895,744 B2
• Filed: 02/07/2003
• Issued: 05/24/2005
• Est. Priority Date: 02/20/2002
• Status: Expired due to Term

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Osawa, Koichi
• Primary Examiner(s): Denion, Thomas
• Assistant Examiner(s): Eshete, Zelalem
• Application Number:
  US10/359,585
• Publication Number:
  US 20030154952A1
• Time in Patent Office: 837 Days
• Field of Search: 123/198.DB, 602/77, 602/74
• US Class Current: 60/277
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60L 2240/445 Temperature
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 2510/0676 Engine temperature
• CPC Class Codes: B60W 2510/068 Engine exhaust temperature
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: F02D 41/0235 in relation with the state of the exhaust gas treating apparatus control of exhaust gas treating apparatus per se F01N
• CPC Class Codes: F02D 41/042 for stopping the engine
• CPC Class Codes: F02N 11/0818 Conditions for starting or stopping the engine or for deactivating the idle-start-stop mode
• CPC Class Codes: F02N 2200/026 Catalyst temperature
• CPC Class Codes: Y02T 10/40 Engine management systems
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

In an operation of an internal combustion engine for a vehicle in which an operation of the internal combustion engine is stopped by a control of a vehicle operation control device during a vehicle operation, the control determination includes a determination that the internal combustion engine is not stopped when a temperature of the catalyst is not equal to or less than a predetermined threshold value.

Claims

1. An operation method of an internal combustion engine for a vehicle including the internal combustion engine and an exhaust gas purification catalyst which is provided in a exhaust system of the internal combustion engine, comprising:

determining whether an operation of the internal combustion engine should be stopped during a vehicle operation;

detecting a temperature of the catalyst; and

determining not to stop the internal combustion engine when the detected temperature of the catalyst is higher than a predetermined threshold value, wherein

the predetermined threshold value is lower than a permissible upper limit value, at which a thermal deterioration of the catalyst is prevented, by at least an increase amount of the catalyst temperature immediately after the stop of the internal combustion engine.

2. The method according to claim 1, further comprising:

detecting an operating state of the vehicle; and

automatically stopping the internal combustion engine based on the detected operating state.

3. The method according to claim 1, wherein

the method is an operation method of an internal combustion engine for a hybrid car which is capable of using both driving force by the internal combustion engine and driving force by a motor as driving force.

4. The method according to claim 3, wherein

when the internal combustion engine is stopped by the control determination, the hybrid car is operated by the driving force by the motor.

5. The method according to claim 1, wherein

the method is an operation method of an internal combustion engine for an economy running car in which the internal combustion engine is temporarily stopped as necessary during a temporary stop of the vehicle.

6. The method according to claim 5, further comprising:

assuming whether a driver has the intention to start the economy running car after the temporary stop, and

wherein if it is assumed that the driver has the intention to start the economy running car, the internal combustion engine is restarted.

7. An operation method of an internal combustion engine for a vehicle including the internal combustion engine and an exhaust gas purification catalyst which is provided in a exhaust system of the internal combustion engine, comprising:

determining whether an operation of the internal combustion engine should be stopped during a vehicle operation;

detecting a temperature of the catalyst; and

not stopping the internal combustion engine when the detected temperature of the catalyst is higher than a predetermined threshold value, even if it is determined that the operation of the internal combustion engine should be stopped, wherein

the predetermined threshold value is lower than a permissible upper limit value, at which a thermal deterioration of the catalyst is prevented, by at least an increase amount of the catalyst temperature immediately after the stop of the internal combustion engine.

8. An operation device of an internal combustion engine of a vehicle, comprising:

a detector that detects a temperature of a catalyst of an exhaust gas purification catalyst which is provided in a exhaust system of the internal combustion engine, and

a controller that determines whether an operation of the internal combustion engine is automatically stopped during a vehicle operation, and that determines not to stop the internal combustion engine when the temperature of the catalyst which is detected by the detector is higher than a predetermined threshold value, wherein

the predetermined threshold value is lower than a permissible upper limit value, at which a thermal deterioration of the catalyst is prevented, by at least an increase amount of the catalyst temperature immediately after the stop of the internal combustion engine.

9. The device according to claim 8, further comprising:

a detector that detects an operating state of the vehicle; and

wherein the controller automatically stops the internal combustion engine based on the operating state detected by the detector.

10. The device according to claim 8, wherein

the vehicle is a hybrid car which is capable of using both driving force by the internal combustion engine and driving force by a motor as driving force, and

when the internal combustion engine is stopped, the controller operates the hybrid car by the driving force by the motor.

11. The device according to claim 8, wherein

the vehicle is an economy running car in which the internal combustion engine is temporarily stopped as necessary during a temporary stop of the vehicle,

the controller assumes whether a driver has an intention to start the economy running car after the temporary stop, and

if it is assumed that the driver has the intention to start the economy running car, the controller restarts the internal combustion engine.