Engine cooling system

Abstract

Provided is an engine cooling system capable of securing a margin up to the heat resistance limit of an engine by means of pre-cooling when deceleration is performed when it is predicted that high-load travel in which the engine needs to be cooled is performed. The engine cooling system is provided with an electric water pump for circulating a coolant between an engine and a radiator of a vehicle, and a grille damper which is provided in front of the radiator and has an adjustable opening degree. When it is predicted that the engine is traveling at a high load on the basis of a high-load traveling history including position information on the map of the vehicle when the engine of the vehicle is in a high load in the past, and current position information on the map of the vehicle, opening control of the grille damper is performed when the vehicle is decelerated, and opening control of the grille damper is performed when the vehicle is decelerated. And rotational speed increase control of the electric water pump is performed.

Description

TECHNICAL FIELD

[0001] The present application relates to an engine cooling system for a vehicle. BACKGROUND

[0002] As a technical document related to an engine cooling system, Japanese Patent Application Publication No. 2020-049996 (JP 2020-049996 A) is known. In this document, an engine cooling system is disclosed that reduces the rotation speed of an electric water pump based on deceleration of a vehicle in which fuel supply to an engine is cut off, and increases the opening degree of a grille shutter to ensure a sense of deceleration while suppressing overcooling of coolant to improve fuel economy.

[0003] PRIOR ART DOCUMENTS

[0004] PATENT DOCUMENT

[0005] Patent Document 1: Japanese Patent Application Publication No. 2020-049996 (JP 2020-049996 A) SUMMARY

[0006] PROBLEMS TO BE SOLVED BY THE INVENTION

[0007] In the above-described conventional system, the grille shutter is opened to increase air resistance, and a sense of deceleration is improved without overcooling due to the reduction in the rotation speed of the water pump. However, in the conventional system, the running conditions of the vehicle cannot be taken into account. Therefore, it is required to perform more appropriate cooling by taking the running conditions of the vehicle into account.

[0008] MEANS FOR SOLVING THE PROBLEMS

[0009] One embodiment of the present application is an engine cooling system including an electric water pump that circulates coolant between an engine and a radiator of a vehicle, and a grille shutter that is provided in front of the radiator and whose opening degree is adjustable, wherein, in a case where it is predicted that the engine is in a high-load running condition based on a high-load running history record including information on a position on a map of the vehicle when the engine was in a high-load state in the past and information on a current position on the map of the vehicle, opening control of the grille shutter is performed when deceleration of the vehicle is performed, and rotation speed increase control of the electric water pump is performed.

[0010] EFFECTS OF THE INVENTION

[0011] According to the present application, in a case where it is predicted that the engine is in a high-load running condition in which cooling of the engine is required, opening control of the grille shutter and rotation speed increase control of the electric water pump are performed when deceleration is performed, and cooling is performed in advance, so that a margin to a heat resistance limit can be ensured. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 is a block diagram that shows an engine cooling system of one embodiment.

[0013] Figure 2 This is a flowchart illustrating an example of the processing of an engine cooling system. Detailed Implementation

[0014] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0015] Figure 1 This is a block diagram illustrating one embodiment of an engine cooling system 100. (As shown...) Figure 1 As shown, the engine cooling system 100 installed in the vehicle includes an electric water pump 4, which is disposed on a pipe 3 connecting the water jacket of the engine 1 to the radiator 2, so that the coolant circulates between the engine 1 and the radiator 2. In addition, the engine cooling system 100 may also include an electric fan for increasing the amount of air passing through the radiator 2.

[0016] In addition, the engine cooling system 100 has a grille damper 6, which is located in front of the radiator 2 in front of the front grille 5 and can adjust the opening (i.e., the size of the opening that connects the front of the vehicle to the engine compartment).

[0017] The electric water pump 4 and the grille damper 6 are electrically connected to the control unit 10 and operate according to control signals from the control unit 10. The control unit 10 outputs control signals to the electric water pump 4 and the grille damper 6 according to various vehicle conditions, causing the speed of the electric water pump 4 to change to adjust the flow rate of the coolant, thereby adjusting the opening of the grille damper 6.

[0018] Specifically, when the engine 1 starts, the control unit 10 outputs a control signal to keep the grille damper 6 closed in order to heat the coolant as soon as possible until the coolant temperature reaches an appropriate range. When the appropriate range is reached, the control unit 10 outputs a control signal to change the opening degree according to the coolant temperature, driving conditions, etc.

[0019] On the other hand, when the engine 1 is under high load, the control unit 10 performs opening control of the grille damper 6 to reduce the temperature of the coolant. The control unit 10 outputs a control signal to set the grille damper 6 to the open state. Then, when the coolant temperature reaches an appropriate range, the control unit 10 outputs a control signal to change the opening degree according to the coolant temperature, driving conditions, etc.

[0020] Furthermore, when the engine 1 is under high load, the control unit 10 performs speed increase control to increase the coolant flow rate of the electric water pump 4. The control unit 10 outputs a control signal such that the speed of the electric water pump 4 is increased compared to the normal state when the engine 1 is not under high load. At the same time, the control unit 10 can also perform electric fan speed increase control to increase the speed of the electric fan compared to the normal state when the engine 1 is not under high load.

[0021] Next, the control unit 10 in this embodiment will be described. The control unit 10 is an electronic control unit having a CPU (Central Processing Unit) and a storage unit. The storage unit is configured, for example, with ROM (Read Only Memory), RAM (Random Access Memory), EEPROM (Electrically Erasable Programmable Read-Only Memory), etc. In the control unit 10, various processes are performed, for example, by the CPU executing a program stored in the storage unit.

[0022] like Figure 1 As shown, the control unit 10 is connected to the vehicle speed sensor 11, the GNSS (Global Navigation Satellite System) receiver 12, the map database 13, and the high-load driving history database 14. The vehicle speed sensor 11 is a sensor that detects the vehicle's speed. The vehicle speed sensor 11 sends the vehicle speed information to the control unit 10.

[0023] The GNSS receiver 12 determines the vehicle's position (e.g., latitude and longitude) by receiving signals from positioning satellites. As an example of the GNSS receiver 12, a GPS (Global Positioning System) receiver can also be used. The GNSS receiver 12 transmits the determined vehicle position information to the control unit 10.

[0024] Map database 13 is a database that stores map information. Map database 13 is formed, for example, in a storage device such as an HDD (Hard Disk Drive) installed in a vehicle.

[0025] The high-load driving history database 14 stores the driving history of the vehicle's engine 1 under high load, i.e., the high-load driving history database. The high-load driving history includes the vehicle's location information on the map when the engine 1 is under high load. High engine load refers to a situation where the engine 1 needs to be actively cooled by the engine cooling system 100. The requirement to cool the engine 1 can be arbitrarily determined by each manufacturer.

[0026] Furthermore, high-load driving history records can also be stored in map database 13. In this case, engine cooling system 100 does not need to have a high-load driving history record database 14. Additionally, the high-load driving history records do not necessarily need to be the driving history records of the same vehicle; driving history records of other vehicles of the same type or with the same type of engine can also be used. Alternatively, high-load driving history records can be obtained from an external server.

[0027] The control unit 10 identifies the current vehicle position on the map based on the current vehicle position information measured by the GNSS receiver 12 and the map information in the map database 13. Based on the current vehicle position on the map and the high-load driving history records in the high-load driving history database 14, the control unit 10 determines whether high-load driving of the vehicle's engine is predicted. For example, if the vehicle enters a high-load zone within a certain distance or within a certain time period where the engine 1 was previously at a high load, the control unit 10 determines that high-load driving of the vehicle's engine is predicted. Furthermore, the vehicle speed of the vehicle speed sensor 11 is also used in determining whether the vehicle has entered a high-load zone within a certain time period.

[0028] When the control unit 10 determines that the vehicle's engine is expected to be under high load, it determines whether the vehicle is decelerating based on the vehicle speed information detected by the vehicle speed sensor 11. If the control unit 10 determines that the vehicle is decelerating, it performs pre-cooling of the engine 1, independent of normal engine cooling requirements. The control unit 10 controls the opening of the grille damper 6 and the increase in the rotational speed of the electric water pump 4. The control unit 10 may also control the increase in the rotational speed of the electric fan.

[0029] Next, refer to Figure 2 The processing of the engine cooling system 100 in this embodiment will be described. Figure 2 The processing shown is performed while the vehicle is in motion.

[0030] like Figure 2 As shown, in step S10, the control unit 10 of the engine cooling system 100 determines whether high-load driving of the vehicle's engine is predicted. Based on the current vehicle location information, map information, and high-load driving history, the control unit 10 determines that high-load driving of the vehicle's engine is predicted when the vehicle enters a high-load range where the engine 1 was previously at a high load within a certain distance or within a certain time.

[0031] If the control unit 10 determines that the vehicle's engine is predicted to be operating under high load (S10: Yes), it proceeds to S11. If the control unit 10 does not determine that the vehicle's engine is predicted to be operating under high load (S10: No), it terminates the current processing.

[0032] In S11, the control unit 10 determines whether the vehicle is decelerating based on the vehicle speed information detected by the vehicle speed sensor 11. If the control unit 10 determines that the vehicle is decelerating (S11: Yes), it proceeds to S12. If the control unit 10 does not determine that the vehicle is decelerating (S11: No), it ends the current processing.

[0033] In S12, the control unit 10 controls the opening of the grille damper 6, the increase in the rotational speed of the electric water pump 4, and the increase in the rotational speed of the electric fan. This allows for pre-cooling of the engine 1. The control unit 10 can also bring the engine 1 into a subcooled state.

[0034] According to the engine cooling system 100 of this embodiment described above, when high-load driving conditions that require cooling of the engine 1 are predicted, cooling is pre-emptively achieved by controlling the opening of the grille damper 6 and increasing the speed of the electric water pump 4 during deceleration, thereby ensuring sufficient cooling capacity up to the heat resistance limit of the engine 1.

[0035] The embodiments of the present invention have been described above, but the present invention is not limited to the embodiments described above. The present invention can be implemented in various ways with different modifications and improvements based on the embodiments described above and on the knowledge of those skilled in the art.

[0036] For example, the opening degree of the grille damper 6 in S12 can be smaller compared to the opening control during normal engine cooling after the engine 1 needs to be cooled. Additionally, the speed increase control of the electric water pump 4 in S12 can also be a lower speed than during normal engine cooling. Similarly, the speed increase control of the electric fan in S12 can also be a lower speed than during normal engine cooling. Furthermore, in S12, the electric fan speed increase control is not mandatory.

[0037] Explanation of reference numerals in the attached figures

[0038] 1…engine, 2…radiator, 3…piping, 4…electric water pump, 6…grille damper, 5…front grille, 10…control unit, 100…engine cooling system.

Claims

1. An engine cooling system comprising: an electric water pump for circulating coolant between the engine and radiator of a vehicle; and a grille damper disposed in front of the radiator and adjustable in opening, wherein... When high-load driving is predicted based on the vehicle's historical driving history, including its location on the map when the engine was under high load in the past, and the current location on the map, the engine cooling system controls the opening of the grille damper and increases the speed of the electric water pump when the vehicle decelerates.

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