WO2021193485A1

WO2021193485A1 - Vehicular cooling device

Info

Publication number: WO2021193485A1
Application number: PCT/JP2021/011570
Authority: WO
Inventors: 惇史勢〆
Original assignee: いすゞ自動車株式会社
Priority date: 2020-03-26
Filing date: 2021-03-22
Publication date: 2021-09-30
Also published as: JP2021154822A

Abstract

Provided is a vehicular cooling device 10 comprising: a cooling circuit 11 in which cooling water W that cools an engine 1 circulates and which has a radiator 20 that cools the cooling water W passing through the interior thereof; a heating device 30 which is configured so as to heat the radiator 20; and a control device 32 which is configured so as to control the heating device 30, wherein the control device 32 is configured so as to perform control to heat the radiator 20 by means of the heating device 30 such that temperature Tw of the radiator 20 approaches the temperature of the cooling water W before the cooling water W passes through the interior of the radiator 20.

Description

Vehicle cooling system

The present disclosure relates to a vehicle cooling device, and more particularly to a vehicle cooling device in which the cooling circuit has a radiator through which cooling water for cooling the engine passes.

In a device that circulates a part of the cooling medium to the heater core, a device that divides the inlet side tank of the radiator into the first chamber and the second chamber and has a heating means for heating the cooling medium inside the second chamber is proposed. (See, for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 2001-26063639

By the way, when the engine is started, the temperature of the radiator may be the temperature according to the outside air temperature. When the engine is started and the cooling water whose temperature has risen to about 80 degrees flows inside the radiator, the radiator rapidly rises from the outside air temperature to the temperature of the cooling water. Such a rapid temperature rise of the radiator causes cold strain in the radiator.

The device described in Patent Document 1 heats the cooling medium flowing from the radiator to the heater core, and when the engine is started, the heated cooling water flows to the cooled radiator as described above. .. Therefore, cold strain was generated in the radiator.

An object of the present disclosure is to provide a vehicle cooling device that suppresses thermal strain generated in a radiator.

The vehicle cooling device of one aspect of the present disclosure that achieves the above object is a cooling circuit in which cooling water for cooling the engine circulates, and includes a cooling circuit having a radiator for cooling the cooling water passing through the inside. The control device includes a heating device configured to heat the radiator and a control device configured to control the heating device, in which the cooling water passes through the inside of the radiator. Previously, the heating device is configured to control the heating of the radiator so that the temperature of the radiator approaches the temperature of the cooling water.

According to one aspect of the present disclosure, the temperature difference between the radiator and the cooling water can be reduced by heating the radiator with a heating device before the cooling water passes through the inside of the radiator. As a result, it is possible to suppress the thermal strain generated in the radiator due to the temperature difference.

FIG. 1 is a configuration diagram illustrating an embodiment of a vehicle cooling device. FIG. 2 is a perspective view illustrating the radiator and the heating device of FIG. FIG. 3 is a flow chart illustrating a control method for the vehicle cooling device according to the embodiment.

Hereinafter, embodiments of the vehicle cooling device in the present disclosure will be described. In the figure, the X direction is the direction in which the cooling air passing through the radiator 20 flows in the front-rear direction of the vehicle, the Y direction is the width direction of the vehicle, and the Z direction is the vertical direction. The white arrow indicates the flow of the cooling air, and the filled arrow indicates the flow of the cooling water W.

As illustrated in FIG. 1, the vehicle cooling device 10 of the embodiment is a device that cools the engine 1, and the cooling water W passes through the cooler 2 of the engine 1 and exchanges heat with the equipment to be cooled. , Cooling the equipment to be cooled. In the present disclosure, examples of the cooler 2 include a water jacket, an intercooler, and a cooler for recirculation exhaust.

The vehicle cooling device 10 includes a cooling circuit 11 in which the cooling water W circulates. The cooling circuit 11 includes a cooling path 14 in which a water pump 12, a cooler 2, a thermostat 13, and a radiator 20 are interposed, and a detour circuit 15 that bypasses the cooling path 14. In the cooling circuit 11, the cooling water W circulates in the order of the water pump 12, the cooler 2, the thermostat 13, the cooling passage 14 in which the radiator 20 is interposed, the detour 15 bypassing the cooling passage 14, and the water pump 12. It is configured to do. Further, the vehicle cooling device 10 includes a cooling fan 16.

The water pump 12 is a mechanical type, and the rotational power from the crankshaft 3 of the engine 1 is transmitted via a power transmission mechanism 4 such as an endless belt or a gear mechanism, and is driven by the rotational power. The rotation speed of the water pump 12 depends on the rotation speed of the engine 1, but the rotation speed may be adjusted by controlling the power transmission mechanism 4. Further, the water pump 12 may be composed of an electric water pump driven by rotational power from an electric motor.

The thermostat 13 is arranged at the branch point of the cooling passage 14 and the detour 15 after passing through the cooler 2. The thermostat 13 has a lifter (not shown) that expands and contracts by a thermal expander having a property of expanding as the temperature of the cooling water W rises and contracting as the temperature of the cooling water W decreases. The lifter expands and contracts according to the temperature to adjust the flow rate of the cooling water W flowing through the cooling passage 14 and the detour. The thermostat 13 is configured so that the cooling water W flows only through the cooling passage 14 in the fully open state and the cooling water W flows only through the detour 15 in the fully closed state. The thermostat 13 may be composed of an electric thermostat that forcibly expands and contracts the lift by electric heating.

In the present embodiment, the cooling circuit 11 is an outlet control type in which the thermostat 13 is arranged in the flow path after passing through the cooler 2 and before passing through the cooling path 14 and the detour 15 in which the radiator 20 is interposed. The outlet control type cooling circuit 11 can improve the air bleeding property and suppress the occurrence of cavitation, which is advantageous for improving the durability, and is particularly suitable for a large vehicle such as a truck. The cooling circuit 11 may be an inlet control type in which the thermostat 13 is arranged in the flow path after passing through the radiator 20 and before passing through the cooler 2 instead of the outlet control type. The inlet control type cooling circuit is more advantageous than the outlet control type cooling circuit 11 in terms of temperature adjustment of the cooling water W.

The radiator 20 is arranged on the front side (left side in FIG. 1) of the vehicle on which the engine 1 is mounted, and the cooling fan 16 is arranged on the rear side of the radiator 20. The radiator 20 is a heat exchanger that cools the cooling water W passing through the inside by using the vehicle speed air and the cooling air by the subsequent cooling fan 16.

The radiator 20 has an inlet tank 21, an outlet tank 22, and a heat exchange core 23. The radiator 20 of the present embodiment is a downflow type radiator in which the inlet tank 21 and the outlet tank 22 are arranged vertically in the Z direction, and the cooling water W flows through the heat exchange core 23 from the upper side to the lower side in the Z direction. The radiator 20 may be a cross-flow type radiator in which the inlet tank 21 and the outlet tank 22 are arranged on the left and right in the Y direction, and the cooling water W flows through the heat exchange core 23 in the Y direction.

The cooling passage 14 is a flow path in which a radiator 20 is provided at an intermediate position thereof and the cooling water W is cooled by the radiator 20. The detour circuit 15 is a flow path in which the cooling water W is not cooled by the radiator 20 by bypassing the cooling path 14.

The cooling fan 16 is a mechanical type, and the rotational power from the crankshaft 3 of the engine 1 is transmitted via the fan clutch 17, and is driven by the rotational power. The temperature zone in which the cooling fan 16 is driven by the fan clutch 17 is adjusted. For example, when the engine 1 is warmed up, the fan clutch 17 stops driving the cooling fan 16. The rotation speed of the cooling fan 16 depends on the rotation speed of the engine 1, but the rotation speed may be adjusted by controlling the fan clutch 17.

The vehicle cooling device 10 of the present embodiment includes a heating device 30, a temperature acquisition device 31, and a control device 32. The control device 32 controls the radiator 20 to be heated by the heating device 30 so that the temperature Tr of the radiator 20 approaches the temperature Tw of the cooling water W before the cooling water W passes through the inside of the radiator 20. Further, the vehicle cooling device 10 controls its heating before the cooling water W passes through the radiator 20.

The heating device 30 is a device that directly heats the heat exchange core 23 of the radiator 20, and is composed of a heating wire 33. The heating device 30 is connected to the battery 6 via a switch. The rotational power from the crankshaft 3 of the engine 1 is transmitted to the battery 6 via a power transmission mechanism 7 such as an endless belt or a gear mechanism, and the battery 6 is charged by a generator 8 driven by the rotational power.

As illustrated in FIG. 2, the heat exchange core 23 of the radiator 20 is composed of a plurality of communication pipes 24 and cooling fins 25. Each of the plurality of communication pipes 24 is a pipe in which one end communicates with the inlet tank 21 and the other end communicates with the outlet tank 22, and the cooling water W passes through the inside thereof. Examples of the communication pipe 24 are tubes made of aluminum or an aluminum alloy and having a thin pipe thickness. The plurality of communication pipes 24 need only be arranged in at least the Y direction, and in the present embodiment, the plurality of communication pipes 24 are arranged in the X direction and the Y direction. The left and right ends of the heat exchange core 23 in the Y direction are composed of a frame and brackets.

The cooling fins 25 are arranged between the communication pipes 24. Examples of the cooling fins 25 include corrugated fins having a zigzag shape so as to be in contact with both adjacent communication pipes 24 and plate fins through which all of the plurality of communication pipes 24 penetrate.

It is desirable that the heating device 30 of the present embodiment directly heats the heat exchange core 23 of the radiator 20, and it is more desirable that the heating device 30 directly heats a plurality of communication pipes 24 constituting the heat exchange core 23.

The heating wire 33 is arranged so as to be in direct contact with the outer surface of the communication pipe 24, and the heating device 30 directly heats the communication pipe 24. The heating wire 33 may be directly in contact with the outer surface of the communication pipe 24, and may be arranged on either the X-direction front surface or the back surface of the communication pipe 24 or one of the Y-direction side surfaces. Further, the heating wire 33 may be arranged inside the communication pipe 24 so as to be in direct contact with the inner surface of the communication pipe 24.

The heating wire 33 of the present embodiment is arranged in a communication pipe 24 that is deformed so as to bend outward in the Y direction due to thermal strain. Specifically, the heating wire 33 is arranged in the communication pipe 24 arranged at both ends 23a in the Y direction of the heat exchange core 23. In the present disclosure, the Y direction of the heat exchange core 23 is orthogonal to both the Z direction, which is the direction in which the cooling water W passing through the heat exchange core 23 flows, and the X direction, which is the direction in which the air passing through the heat exchange core 23 flows. It is the direction to do. Further, in the present disclosure, the Y-direction both end portions 23a of the heat exchange core 23 are portions excluding the central portion of the heat exchange core 23, and a predetermined number (for example, 3 to 7) from both ends in the Y direction toward the central portion. It is a part including the communication pipe 24 of the above.

It is desirable that the heating temperature of the heating device 30 is set to a temperature at which deposits adhering to the surface of the heat exchange core 23 do not burn, for example, a temperature of less than 200 ° C. Further, by setting the heating temperature of the heating device 30 to a temperature higher than the maximum temperature reached by the cooling water W, it is advantageous to quickly raise the temperature of the radiator 20.

As illustrated in FIG. 1, the temperature acquisition device 31 is a device that acquires the temperature Tw of the cooling water W, and is arranged in the flow path between the cooler 2 and the thermostat 13.

The control device 32 is a device that controls the drive of the heating device 30, and is electrically connected to a switch that controls the drive of the heating device 30, a temperature acquisition device 31, and an ignition switch 9.

The control device 32 is hardware composed of a central processing unit (CPU) that performs various information processing, an internal storage device that can read and write programs and information processing results used for performing various information processing, and various interfaces. be.

In the control device 32, the set temperature Ta is set in the internal storage device in advance. Further, the control device 32 has a functional element for determining the drive of the heating device 30. The functional elements are stored in the internal storage device as a program, and are executed by the central processing unit in a timely manner. In addition to the program, the functional element may be composed of a programmable controller (PLC) or an electric circuit that functions independently.

The set temperature Ta is a value obtained in advance by an experiment, a test, or a simulation. The set temperature Ta is set so that it can be determined when the cooling water W starts to flow from the thermostat 13 through the cooling passage 14, and more specifically, it can be determined when the thermostat 13 starts to open from the fully closed state. Set.

As illustrated in FIG. 3, the control method of the vehicle cooling device 10 will be described as a function of the control device 32. This control method is performed at the time of cold start of the engine 1. In the present disclosure, it is assumed that the heat exchange core 23 of the radiator 20 is started from a state equal to the outside air temperature or a temperature lower than the outside air temperature at the time of cold start.

This control method is a method in which the temperature of the radiator 20 is raised by the heating device 30 before the cooling water W passes through the heat exchange core 23 of the radiator 20 to bring the temperature of the radiator 20 closer to the temperature Tw of the cooling water W.

This control method is started when the engine 1 is started by the ignition switch 9. When the control method starts, the control device 32 drives the heating device 30 to control the radiator 20 to be heated (S110). Then, the control device 32 acquires the temperature Tw of the cooling water W via the temperature acquisition device 31 (S120). Then, the control device 32 determines whether or not the acquired temperature Tw is equal to or higher than the set temperature Ta (S130). When the temperature Tw is lower than the set temperature Ta, the thermostat 13 is in a fully closed state, and the cooling water W does not flow through the cooling passage 14 but flows only through the detour circuit 15. On the other hand, when the temperature Tw is equal to or higher than the set temperature Ta (including the case where the temperature Tw is equal to the set temperature Ta), the thermostat 13 starts to open from the fully closed state, and a part of the cooling water W flows through the detour 15. The rest flows through the cooling passage 14.

When it is determined that the temperature Tw is lower than the set temperature Ta (S130: NO), the control device 32 keeps driving the heating device 30 and continues heating the radiator 20. On the other hand, when it is determined that the temperature Tw is equal to or higher than the set temperature Ta (S130: YES), the control device 32 stops driving the heating device 30, and this control method ends.

The vehicle cooling device 10 of the present disclosure drives the heating device 30 before the cooling water W passes through the inside of the radiator 20 at the time of cold start of the engine 1 to heat the radiator 20 and raise the temperature. Therefore, according to the vehicle cooling device 10 of the present disclosure, even if the thermostat 13 is opened by heating the radiator 20 by the heating device 30 and the cooling water W actually starts to pass through the inside of the radiator 20, the radiator 20 and its own. The temperature difference from the cooling water W can be reduced. As a result, it is possible to suppress the thermal strain generated in the radiator 20 due to the temperature difference.

The control of heating the radiator 20 by the heating device 30 of the vehicle cooling device 10 is not limited to the cold start of the engine 1 by the ignition switch 9. The heating control of the present disclosure may be performed from the state in which the cooling water W has not passed through the inside of the radiator 20 to before the cooling water W has passed.

Specifically, the heating control should be performed when the temperature Tw of the cooling water W is lower than the set temperature Ta, and stopped when the temperature Tw is equal to or higher than the set temperature Ta. Therefore, instead of starting the engine 1 by the ignition switch 9, the above control method is started so that the accessory power supply can be energized by the ignition switch 9, and the temperature Tw acquired by the temperature acquisition device 31 sets the set temperature Ta. It may be when it is judged that it falls below.

Further, the heating control may be performed when there is a temperature difference between the radiator 20 and the cooling water W. For example, a sensor that directly acquires the temperature of the radiator 20 may be added to start the above control method when the temperature of the radiator 20 is lower than the temperature Tw of the cooling water W.

Further, the heating control may be performed, for example, when the heat exchange core 23 of the radiator 20 becomes a temperature equal to or lower than the outside air temperature during coasting in a state where the operation of the engine 1 is stopped. .. In that case, the control device 32 may determine whether or not to control the heating based on the traveling time of the coasting running in the state where the operation of the engine 1 is stopped.

Further, the heating control may determine whether or not the start of the engine 1 by the ignition switch 9 is a cold start. For example, when the outside air temperature is lower than a predetermined temperature by using a sensor that acquires the outside air temperature, the case where the engine 1 is started by the ignition switch 9 may be determined as a cold start.

The heating control is stopped when the temperature Tw of the cooling water W becomes equal to or higher than the set temperature Ta, that is, when the cooling water W passes through the radiator 20. As a result, it is possible to avoid a situation in which the cooling performance of the cooling water W by the radiator 20 is deteriorated by heating by the heating device 30.

The heating control is such that when the temperature of the heat exchange core 23 of the radiator 20 reaches the temperature Tw of the cooling water W, the temperature of the heat exchange core 23 is maintained without being raised to a higher temperature. Is preferable.

The vehicle cooling device 10 of the present embodiment is arranged in a communication pipe 24 arranged at both ends 23a in the Y direction of the heat exchange core 23, which is a communication pipe 24 in which the heating wire 33 of the heating device 30 is deformed by cold heat strain. .. As a result, it is possible to prevent the communication pipes 24 arranged at both ends 23a of the heat exchange core 23 in the Y direction from bending outward in the Y direction due to cold heat strain.

The heating wire 33 of the heating device 30 is not limited to the configuration in which it is arranged only in the communication pipes 24 arranged at both ends 23a in the Y direction of the heat exchange core 23. For example, the heating wire 33 may be arranged in each of all the communication pipes 24 constituting the heat exchange core 23. By arranging the heating wires 33 in all the communication pipes 24, it is advantageous to quickly heat the entire heat exchange core 23. On the other hand, if the heating wires 33 are arranged in all the communication pipes 24, the power consumption during heating increases. Therefore, it is desirable that the heating wire 33 is arranged in some communication pipes 24 including at least the communication pipes 24 arranged at both ends 23a in the Y direction of the heat exchange core 23.

This application is based on a Japanese patent application filed on March 26, 2020 (Japanese Patent Application No. 2020-055836), the contents of which are incorporated herein by reference.

The vehicle cooling device of the present disclosure is useful in that it can suppress the thermal strain generated in the radiator.

1 Engine 10 Vehicle cooling device 11 Cooling circuit 20 Radiator 30 Heating device 31 Temperature acquisition device 32 Control device

Claims

A cooling circuit in which cooling water for cooling the engine circulates, and a cooling circuit having a radiator for cooling the cooling water passing through the inside.
A heating device configured to heat the radiator,
A control device configured to control the heating device, and
The control device is configured to control the radiator to be heated by the heating device so that the temperature of the radiator approaches the temperature of the cooling water before the cooling water passes through the inside of the radiator. Vehicle cooling system.
The radiator has an inlet tank, an outlet tank, and a heat exchange core.
The vehicle cooling device according to claim 1, wherein the heating device is configured to directly heat the heat exchange core.
The heat exchange core has a plurality of communication pipes having one end communicating with the inlet tank and the other end communicating with the outlet tank, and cooling fins arranged between the plurality of communication pipes.
The heating device is arranged at both ends of the plurality of communication pipes in a direction orthogonal to at least a direction in which the cooling water of the heat exchange core flows and a direction in which air passing through the heat exchange core flows. The vehicle cooling device according to claim 2, which is configured to directly heat the communication pipe.
The control device according to any one of claims 1 to 3, wherein the control device is connected to an ignition switch and is configured to control heating when the engine is cold-started by the ignition switch. Vehicle cooling system.
The cooling circuit is arranged at either a cooling path in which the radiator is interposed, a detour that bypasses the cooling path, a branch point between the cooling path and the detour, or a confluence of the cooling path and the detour. With a thermostat that has been
A temperature acquisition device for acquiring the temperature of the cooling water is arranged in the cooling circuit.
The control device controls the heating when the temperature of the cooling water acquired by the temperature acquisition device is equal to or higher than a set temperature set by the thermostat so that the cooling water can be determined to flow through the cooling path. The vehicle cooling device according to any one of claims 1 to 4, which is configured to stop the vehicle.
The vehicle cooling device according to claim 5, wherein the control device is configured to control heating when the temperature of the cooling water acquired by the temperature acquisition device is lower than the set temperature.