Method and device for cooling a motor vehicle engine

• US 20030196613A1
• Filed: 12/23/2002
• Published: 10/23/2003
• Est. Priority Date: 02/03/2000
• Status: Active Grant

• Current Assignee: Peugeot Citroen Automobile SA (Stellantis NV)
• Original Assignee: Peugeot Citroen Automobile SA (Stellantis NV)
• Inventors: Le Lievre, Armel, Tomasseli, Ludovic
• Granted Patent: US 7,011,049 B2
• Time in Patent Office: Days
• US Class Current: 123/41.31
• CPC Class Codes: F01P 11/028 Deaeration devices
• CPC Class Codes: F01P 2007/146 using valves
• CPC Class Codes: F01P 2023/00 Signal processing; Details thereof
• CPC Class Codes: F01P 2025/08 Temperature
• CPC Class Codes: F01P 2025/12 Cabin temperature
• CPC Class Codes: F01P 2025/13 Ambient temperature
• CPC Class Codes: F01P 2025/60 Operating parameters
• CPC Class Codes: F01P 2025/62 Load
• CPC Class Codes: F01P 2025/64 Number of revolutions
• CPC Class Codes: F01P 2025/66 Vehicle speed
• CPC Class Codes: F01P 2060/02 Intercooler
• CPC Class Codes: F01P 2060/04 Lubricant cooler
• CPC Class Codes: F01P 2060/08 Cabin heater
• CPC Class Codes: F01P 2060/10 Fuel manifold
• CPC Class Codes: F01P 7/048 using electrical drives
• CPC Class Codes: F01P 7/164 by varying pump speed
• CPC Class Codes: F01P 7/167 by adjusting the pre-set temperature according to engine parameters, e.g. engine load, engine speed
• CPC Class Codes: F02M 26/28 with liquid-cooled heat exchangers
• CPC Class Codes: F02M 26/33 controlling the temperature of the recirculated gases
• CPC Class Codes: F02M 31/042 Combustion air
• CPC Class Codes: Y02T 10/12 : Improving ICE efficiencies

Abstract

A method for cooling a motor vehicle engine consists in regulating the volume and the flow rate of a coolant fluid in a hydraulic circuit provided with a degassing bypass hose equipped with an electronically controlled proportional actuator and with means forming direct return of fluid or bypass. The method comprises a step of determining the temperature of the cooling liquid, a step of comparing the temperature of the cooling liquid with a first and second threshold temperature, and a step of controlling the opening of the actuator such that, when the fluid temperature is between the first and the second threshold temperatures, the degree at which the actuator is opened is at least temporarily proportional to the cooling fluid temperature. The invention also concerns a device for cooling a motor vehicle engine.

Claims

1. Method for cooling a motor vehicle engine, which consists in regulating the volume and the flow rate of a cooling fluid in a hydraulic circuit (2) provided with a branch (5) equipped with an electronically controlled proportional actuator (15) and provided with means (10) forming direct return of fluid or bypass, characterized in that it comprises a step of determining the temperature (T) of the cooling fluid, a step of comparing the temperature (T) determined with a first (T₁) and a second (T₂) specified threshold temperatures, and a step of controlling the opening of the actuator, so that, when the temperature (T) of the fluid is between the first (T₁) and the second (T₂) threshold temperatures, the degree of opening of the actuator is at least temporarily proportional to the temperature (T) of the cooling fluid.

2. Method according to claim 1, characterized in that, when the temperature (T) of the fluid is lower than the first threshold temperature (T₁), the method comprises a step of cutting off, or limiting to a specified leakage flow rate, the circulation of the fluid in the bypass branch (5).

4. Device according to claim 2, characterized in that, when the temperature (T) of the fluid is lower than the first threshold temperature (T₁), the control means (19) cut off, or limit to a specified leakage flow rate, the circulation of the fluid in the bypass branch (5).

5. Device according to claim 2 or 3, characterized in that, when the temperature (T) of the fluid is higher than the second threshold temperature (T₂), the control means (19) control at least temporarily the opening of the actuator (15).

7. Device according to any one of claims 1 to 6, characterized in that, when the temperature (T) of the liquid is between the first (T₁) and the second (T₂) threshold temperatures, the opening of the actuator (15) of the bypass branch (5) increases when the temperature (T) of the fluid increases, and decreases when the temperature (T) of the fluid decreases, such that the curve representative of the opening (15) of the actuator as a function of the temperature of the fluid exhibits a hysteresis (H).

8. Device according to claim 7, characterized in that the increase in the opening of the actuator (15) begins after the temperature (T) of the liquid exceeds the first reference temperature (T₁) by a specified first value (E).

9. Device according to claim 7 or 8, characterized in that the decrease in the opening of the actuator (15) begins after the temperature (T) of the liquid becomes lower than the second reference temperature (T₂) by a specified first value (E).

10. Device according to claim 5, characterized in that the circuit (2) comprises a branch (4) equipped with an actuator (14) and provided with means (9) forming radiator, and in that, when the temperature of the fluid is higher than the second threshold temperature (T₂), the control means (19) control the actuator (15) of the bypass branch (5) as a function of the opening and closing of the actuator (14) of the radiator branch (4), so as, on the one hand, to close the actuator (15) of the bypass branch (5) when the actuator (14) of the radiator branch (4) is opened, and, on the other hand, to open the actuator (15) of the bypass branch (5) when the actuator (14) of the radiator branch (4) is closed, the closings and openings of the actuator (15) of the bypass branch (5) being performed simultaneously, or with a specified temperature offset (R), relative to the openings and closings of the actuator (14) of the radiator branch (4).

11. Device according to claim 10, characterized in that the actuator (14) of the radiator branch (4) is of the proportional type, and in that the opening of the actuator (15) of the bypass branch is inversely proportional to the opening of the actuator (14) of the radiator branch (4).

12. Device according to claim 10, characterized in that the device comprises ventilating means (30), or a “

motor ventilation unit”

, adapted to cooperate with the means (9) forming radiator, the control means (19) ensuring the control of the ventilation means (30) as a function of the temperature of the cooling liquid, so that the rotational speed of the ventilation means (30) increases when the temperature (T) of the cooling liquid increases.

13. Device according to claim 12, characterized in that the increase in the rotational speed (V) of the ventilation means (30) is controlled as a function of the speed

14. Device according to claim 13, characterized in that the rotational speed of the ventilation means (30) as a function of the temperature (T) of the cooling liquid is depicted by a line whose slope is proportional to the speed

3. Device for cooling a motor vehicle engine, of the type comprising a hydraulic circuit (2) of cooling fluid, associated with a pump (3) for circulating it through the engine (1) of the vehicle and different branches (4, 5, 6, 7, 8, 44, 45) of the circuit, in which are arranged thermal equipment (9, 10, 11, 12, 13, 140, 150, 160) of the vehicle, at least some of the branches (4, 5, 6, 7, 8, 44) of the circuit (2) being equipped with electronically controlled actuators (14, 15, 16, 17, 18, 29) to regulate the circulation of the fluid in these branches, the device comprising means (22) for collecting information relating to the operation conditions of the vehicle, connected to means (19) for controlling the operation of the actuators (14, 15, 16, 17, 18, 29), in order to regulate the volume and the flow rate of fluid circulating in the hydraulic circuit (2) so as to optimize the operation of the engine (1), characterized in that the circuit (2) comprises a branch (5) equipped with an electronically controlled proportional actuator (15) and provided with means (10) forming direct return of fluid or bypass, the information collection means (22) being adapted to determine the temperature (T) of the cooling fluid so that, when the temperature of the fluid is between a first (T₁) and a second (T₂) threshold temperatures, the degree of the opening of the actuator (15) is at least temporarily proportional to the temperature (T) of the cooling fluid.

6. Device according to any one of claims I to 5, characterized in that, when the temperature (T) of the fluid is lower than the first threshold temperature (T₁), the control means (19) partially open the actuator (15), so as to ensure a leakage flow rate in the bypass branch (5) in the order of {fraction (1/50)} to {fraction (1/5)} approximately of the maximum flow of the bypass branch (5).