VEHICLE AND METHOD FOR CONTROLLING THE SAME

• US 20130255600A1
• Filed: 12/24/2010
• Published: 10/03/2013
• Est. Priority Date: 12/24/2010
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Teraya, Ryuta
• Granted Patent: US 8,991,338 B2
• Time in Patent Office: Days
• US Class Current: 123/41.02
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/30 including control of auxiliary equipment, e.g. air-conditioning compressors or oil pumps
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 2510/0676 Engine temperature
• CPC Class Codes: B60W 2710/0688 Engine temperature
• CPC Class Codes: F01P 11/16 concerning coolant temperature F01P11/20 takes precedence
• CPC Class Codes: F01P 2025/30 Engine incoming fluid temperature
• CPC Class Codes: F01P 7/164 by varying pump speed
• CPC Class Codes: F02D 29/02 peculiar to engines driving vehicles; peculiar to engines driving variable pitch propellers
• CPC Class Codes: F02N 11/04 the motors being associated with current generators
• 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 2011/0888 DC/DC converters
• CPC Class Codes: F02N 2200/023 Engine temperature
• CPC Class Codes: Y02T 10/40 Engine management systems
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

A vehicle includes an engine capable of being intermittently stopped after it is started; a water pump for circulating cooling water, and an ECU. When the cooling water has low temperature the ECU controls the water pump to limit the flow rate of the cooling water to be smaller than when the cooling water has high temperature. When the cooling water has a limited flow rate the ECU sets lower a threshold value of the cooling water'"'"'s temperature for permitting intermittently stopping the engine than when the cooling water does not have a limited flow rate. When the cooling water has a limited flow rate the engine can nonetheless be intermittently stopped at an appropriate time.

Claims

1. A vehicle comprising:

an internal combustion engine capable of being intermittently stopped after said internal combustion engine is started;

a pump for circulating a cooling medium for cooling said internal combustion engine; and

a control device for controlling said internal combustion engine,

when said cooling medium has low temperature, said control device controlling said pump to limit a flow rate of said cooling medium to be smaller than when said cooling medium has high temperature,

when said flow rate is limited, said control device relaxing a condition applied to permit intermittently stopping said internal combustion engine, as compared with when said flow rate is not limited.

2. The vehicle according to claim 1, wherein said control device relaxes said condition applied to permit intermittently stopping said internal combustion engine when said flow rate is limited and an operation period of time from start of said internal combustion engine is larger than a reference period of time.

3. The vehicle according to claim 2, further comprising a temperature detection unit provided at a cooling piping coupled with said internal combustion engine and a radiator for cooling said cooling medium, for detecting a temperature of said cooling medium.

4. The vehicle according to claim 2, wherein when said flow rate is not limited, said control device permits intermittently stopping said internal combustion engine in response to said cooling medium having exceeded a first threshold value in temperature, whereas when said flow rate is limited, said control device permits intermittently stopping said internal combustion engine in response to said cooling medium having exceeded in temperature a second threshold value lower than said first threshold value.

5. The vehicle according to claim 2, wherein when said flow rate is not limited, said control device permits intermittently stopping said internal combustion engine in response to said cooling medium having exceeded a first threshold value in temperature, whereas when said flow rate is limited, said control device permits intermittently stopping said internal combustion engine in response to said internal combustion engine having an in-cylinder temperature, as estimated from an operational status of said internal combustion engine, having exceeded a second threshold value higher than said first threshold value.

6. The vehicle according to claim 5, wherein said operational status of said internal combustion engine includes at least one of:

an amount of air introduced into said internal combustion engine;

a rotational speed of said internal combustion engine; and

a timing to ignite said internal combustion engine.

7. The vehicle according to claim 1, further comprising:

an electric power storage device; and

a rotating electric machine using electric power received from said electric power storage device for generating a driving force for causing the vehicle to travel.

9. The vehicle according to claim 2, further comprising:

an electric power storage device; and

a rotating electric machine using electric power received from said electric power storage device for generating a driving force for causing the vehicle to travel.

10. The vehicle according to claim 3, further comprising:

an electric power storage device; and

a rotating electric machine using electric power received from said electric power storage device for generating a driving force for causing the vehicle to travel.

11. The vehicle according to claim 4, further comprising:

an electric power storage device; and

a rotating electric machine using electric power received from said electric power storage device for generating a driving force for causing the vehicle to travel.

12. The vehicle according to claim 5, further comprising:

an electric power storage device; and

a rotating electric machine using electric power received from said electric power storage device for generating a driving force for causing the vehicle to travel.

13. The vehicle according to claim 6, further comprising:

an electric power storage device; and

a rotating electric machine using electric power received from said electric power storage device for generating a driving force for causing the vehicle to travel.

8. A method for controlling a vehicle including an internal combustion engine capable of being intermittently stopped after said internal combustion engine is started, a pump for circulating a cooling medium for cooling said internal combustion engine, and a control device for controlling said internal combustion engine, the method comprising the steps of:

controlling said pump to limit a flow rate of said cooling medium when said cooling medium has low temperature to be smaller than when said cooling medium has high temperature; and

relaxing a condition applied to permit intermittently stopping said internal combustion engine when said flow rate is limited, as compared with when said flow rate is not limited.