Engine cooling system

Abstract

To provide an engine cooling system capable of securing a margin up to a heat resistance limit of an engine by cooling the engine in advance when deceleration is performed when high load traveling requiring cooling of the engine is expected.SOLUTION: An engine cooling system includes an electric water pump configured to circulate a coolant between an engine and a radiator of a vehicle, and a grille shutter provided in front of the radiator and configured to adjust an opening degree. The engine cooling system performs opening control of the grille shutter and rotation speed increase control of the electric water pump when deceleration of the vehicle is performed in a case where engine high load traveling is expected based on a high load traveling history including position information on a map of a vehicle in which an engine of the vehicle had a high load in the past and current position information on the map of the vehicle.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an engine cooling system for use in a vehicle. [Background technology]

[0002] Japanese Patent Application Laid-Open Publication No. 2020-049996 is a known technical document related to this technology. This publication describes an engine cooling system that reduces the rotation speed of an electric water pump when a vehicle decelerates and cuts off the fuel supply to the engine, and increases the opening of a grille shutter to ensure a sense of deceleration while suppressing overcooling of the coolant and improving fuel efficiency. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-049996 Summary of the Invention [Problem to be solved by the invention]

[0004] The conventional system described above opens the grille shutter to increase air resistance, improving the feeling of deceleration while reducing the water pump's rotation speed to prevent overcooling. However, the conventional system does not take into account the vehicle's driving conditions. Therefore, there is a need for a system that provides more appropriate cooling by taking into account the vehicle's driving conditions. [Means for solving the problem]

[0005] One aspect of the present invention is an engine cooling system that includes an electric water pump for circulating coolant between a vehicle's engine and radiator, and a grill shutter that is located in front of the radiator and has an adjustable opening.When high-load driving of the engine is expected based on a high-load driving history including location information on a map of vehicles where the vehicle's engine has been under high load in the past, and location information on a map of the current vehicle, when the vehicle decelerates, the grill shutter is controlled to open and the rotation speed of the electric water pump is controlled to increase. [Effects of the Invention]

[0006] According to the present invention, when deceleration is performed in a situation where high-load driving that requires engine cooling is expected, the grille shutter is controlled to open and the rotation speed of the electric water pump is controlled to increase, thereby cooling the engine in advance and ensuring a margin up to the heat-resistant limit. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a block diagram illustrating an engine cooling system according to an embodiment. [Figure 2] 4 is a flowchart illustrating an example of a process of the engine cooling system. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0009] Fig. 1 is a block diagram showing an engine cooling system 100 according to one embodiment. As shown in Fig. 1, the engine cooling system 100 provided in a vehicle is disposed on a pipe 3 connecting a water jacket of an engine 1 and a radiator 2, and includes an electric water pump 4 that circulates coolant between the engine 1 and the radiator 2. The engine cooling system 100 may also include an electric fan for increasing the amount of air passing through the radiator 2.

[0010] The engine cooling system 100 is also provided with a grille shutter 6 that is provided on a front grille 5 in front of the radiator 2 and has an adjustable opening (that is, the size of the opening that connects the front of the vehicle with the inside of the engine compartment).

[0011] The electric water pump 4 and the grille shutter 6 are electrically connected to the control unit 10 and are operated by control signals from the control unit 10. The control unit 10 outputs control signals to the electric water pump 4 and the grille shutter 6 according to various conditions of the vehicle, and changes the rotation speed of the electric water pump 4 to adjust the flow rate of the coolant and adjust the opening degree of the grille shutter 6.

[0012] Specifically, when starting the engine 1, the control unit 10 outputs a control signal to close the grill shutter 6 in order to quickly warm the coolant until the temperature of the coolant reaches an appropriate range, and when the temperature reaches the appropriate range, outputs a control signal to change the opening degree depending on the coolant temperature, driving conditions, etc.

[0013] Meanwhile, the control unit 10 executes opening control of the grill shutter 6 to open the grill shutter 6 in order to lower the temperature of the coolant when the engine 1 is under high load, etc. The control unit 10 outputs a control signal to open the grill shutter 6. Thereafter, when the temperature of the coolant reaches an appropriate range, the control unit 10 outputs a control signal to change the opening degree depending on the temperature of the coolant, the driving state, etc.

[0014] Furthermore, when the engine 1 is under high load, the control unit 10 performs rotation speed increase control to increase the flow rate of coolant from the electric water pump 4. The control unit 10 outputs a control signal to increase the rotation speed of the electric water pump 4 compared to normal times when the engine 1 is not under high load. In addition, the control unit 10 may perform electric fan rotation speed increase control to increase the rotation speed of the electric fan compared to normal times when the engine 1 is not under high load.

[0015] 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 composed of, for example, a ROM (Read Only Memory), a RAM (Random Access Memory), and an EEPROM (Electrically Erasable Programmable Read-Only Memory). The control unit 10 performs various processes by, for example, causing the CPU to execute programs stored in the storage unit.

[0016] 1, the control unit 10 is connected to a vehicle speed sensor 11, a GNSS (Global Navigation Satellite System) receiving unit 12, a map database 13, and a high-load driving history database 14. The vehicle speed sensor 11 is a sensor that detects the vehicle speed of the vehicle. The vehicle speed sensor 11 transmits vehicle speed information to the control unit 10.

[0017] The GNSS receiver 12 measures the vehicle's position (e.g., the latitude and longitude of the vehicle) by receiving signals from positioning satellites. A GPS (Global Positioning System) receiver may be used as an example of the GNSS receiver 12. The GNSS receiver 12 transmits the measured vehicle position information to the control unit 10.

[0018] The map database 13 is a database that stores map information and is formed in a storage device such as a hard disk drive (HDD) mounted on the vehicle.

[0019] The high-load driving history database 14 is a database that stores high-load driving history, which is a history of driving under high load of the vehicle's engine 1. The high-load driving history includes information on the vehicle's location on a map when the vehicle's engine 1 was under high load. A high engine load refers to a situation in which active cooling of the engine 1 by the engine cooling system 100 is required. The conditions under which cooling of the engine 1 is required can be determined arbitrarily by each manufacturer.

[0020] The high-load driving history may be stored in the map database 13. In that case, the engine cooling system 100 does not need to include the high-load driving history database 14. The high-load driving history does not necessarily have to be the driving history of the same vehicle, but may be the driving history of another vehicle of the same model, or may be the driving history of another vehicle equipped with the same model engine. The high-load driving history may be acquired from an external server.

[0021] The control unit 10 recognizes the current vehicle position information on the map based on the current vehicle position information measured by the GNSS receiving unit 12 and the map information in the map database 13. The control unit 10 determines whether or not the vehicle is expected to be operating under high engine load based on the current vehicle position information on the map and the high-load driving history in the high-load driving history database 14. The control unit 10 determines that the vehicle is expected to be operating under high engine load, for example, when the vehicle enters a high-load section where the engine 1 was previously under high load within a certain distance or a certain time period. Note that the vehicle speed measured by the vehicle speed sensor 11 is also used to determine whether or not the vehicle will enter a high-load section within the certain time period.

[0022] When the control unit 10 determines that the vehicle is expected to be running under high engine load, it determines whether the vehicle is decelerating based on vehicle speed information detected by the vehicle speed sensor 11. When the control unit 10 determines that the vehicle is decelerating, it performs pre-cooling of the engine 1 regardless of the normal engine cooling requirements. The control unit 10 controls the grille shutter 6 to open and the electric water pump 4 to increase the rotation speed. The control unit 10 may also control the electric fan rotation speed to increase.

[0023] Next, the processing of the engine cooling system 100 according to this embodiment will be described with reference to Fig. 2. The processing shown in Fig. 2 is executed while the vehicle is running.

[0024] 2, the control unit 10 of the engine cooling system 100 determines whether or not a high engine load running of the vehicle is expected in S10. Based on the current vehicle position information, map information, and high load running history, the control unit 10 determines that a high engine load running of the vehicle is expected when the vehicle enters a high load section where the engine 1 previously experienced a high load within a certain distance or a certain time period.

[0025] If the control unit 10 determines that the vehicle is expected to run under a high engine load (S10: YES), the control unit 10 proceeds to S11. If the control unit 10 does not determine that the vehicle is expected to run under a high engine load (S10: NO), the control unit 10 ends this processing.

[0026] 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), the control unit 10 proceeds to S12. If the control unit 10 does not determine that the vehicle is decelerating (S11: NO), the control unit 10 ends this processing.

[0027] In S12, the control unit 10 controls to open the grille shutter 6, to increase the rotation speed of the electric water pump 4, and to increase the rotation speed of the electric fan. This allows the engine 1 to be pre-cooled. The control unit 10 may also put the engine 1 into a supercooled state.

[0028] According to the engine cooling system 100 of this embodiment described above, when deceleration is performed in anticipation of high-load driving that requires cooling of the engine 1, the grille shutter 6 is opened and the rotation speed of the electric water pump 4 is increased to cool the engine 1 in advance, thereby ensuring a margin up to the heat resistance limit of the engine 1.

[0029] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. The present invention can be embodied in various forms, including the above-described embodiments, with various modifications and improvements made based on the knowledge of those skilled in the art.

[0030] For example, the opening control of the grille shutter 6 in S12 may be performed to a smaller degree than the opening control in the normal engine cooling process that is performed after the engine 1 needs to be cooled. Also, the control to increase the rotation speed of the electric water pump 4 in S12 may be performed to a lower rotation speed than the rotation speed in the normal engine cooling process. Similarly, the control to increase the rotation speed of the electric fan in S12 may be performed to a lower rotation speed than the rotation speed in the normal engine cooling process. Note that the control to increase the rotation speed of the electric fan in S12 is not essential. [Explanation of symbols]

[0031] 1...engine, 2...radiator, 3...piping, 4...electric water pump, 6...grille shutter, 5...front grille, 10...control unit, 100...engine cooling system

Claims

[Claim 1] An engine cooling system including an electric water pump for circulating coolant between a vehicle engine and a radiator, and a grill shutter that is provided in front of the radiator and has an adjustable opening, An engine cooling system that, when the vehicle is decelerated, controls the grille shutter to open and controls the electric water pump to increase its rotation speed when high-load driving is predicted based on a high-load driving history including location information on a map of the vehicle where the engine of the vehicle was previously under high load and current location information on the map of the vehicle.

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