JPS6224746Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a cooling device for an internal combustion engine, such as an automobile engine.

Conventionally, in water-cooled cooling systems, which are most commonly used in automobile engines, when heat is exchanged with the radiator, the temperature difference between the cooling water and the outside air is not that large, so the heat dissipation efficiency of the radiator is low. This inevitably requires a large radiator and a correspondingly large diameter cooling fan, which increases the size of the entire device and causes problems such as large wind noise and fan noise generated by the radiator.

Therefore, the present applicant previously proposed a cooling device for an internal combustion engine (Japanese Patent Application No. 56-28849) that improves heat dissipation efficiency by utilizing the heat of vaporization of a cooling medium. This system stores a liquid phase coolant in the engine's water jacket and cools the engine by evaporating the coolant, while a compressor raises the temperature and pressure of the coolant vapor extracted from the engine. After that, it is condensed and liquefied in a condenser, and this liquefied coolant is circulated and supplied to the engine's water jacket again.In a condenser equivalent to a conventional radiator, the temperature difference between the coolant and the outside air is Since a large amount of heat can be obtained, the heat dissipation efficiency can be improved and the device can be made smaller.

By the way, in a cooling system that uses steam, the vaporization temperature of the cooling medium varies depending on the pressure inside the water jacket of the engine. It is installed at the steam outlet of the water jacket to regulate the pressure inside the water jacket to a substantially constant level.

However, with the regulator valve described above, the amount of steam flowing out is proportional to the pressure inside the water jacket, so if the amount of steam generated increases under high load, the pressure inside the water jacket increases, making it difficult to maintain the set temperature of the cooling system. It becomes difficult to maintain the

In view of the above points, this invention provides a flow rate adjustment valve at the steam outlet of the water jacket, and mechanically controls the opening degree of this flow rate adjustment valve so that it increases in accordance with the increase in the amount of heat generated. In particular, the purpose is to prevent the pressure inside the water jacket from increasing during high loads and to maintain the temperature of the cooling system stably.

Hereinafter, one embodiment of this invention will be described in detail based on the drawings.

The figure schematically shows the configuration of the cooling device according to this invention. Reference numeral 1 indicates an engine, and the engine 1 has a water jacket 4 formed airtight on a cylinder block 2 and a cylinder head 3. In this water jacket 4, a liquid phase cooling medium, for example, cooling water made by adding some additives to water, is stored up to an appropriate level. Therefore, this cooling water boils due to the heat of the engine 1, generates cooling medium vapor, and uses the heat of vaporization to remove heat from the engine 1 and cool each part of the engine 1. The steam generated here is discharged from a steam outlet 5 through a steam passage 7 in which a flow rate regulating valve 6 is interposed, and is introduced into a compressor 8.

The compressor 8 adiabatically compresses the steam that has passed through the flow rate regulating valve 6 and sends it to the condenser 9 after making it higher in temperature and pressure than when it is discharged from the engine. The condenser 9 is installed at the front of the vehicle in a manner similar to a conventional radiator so that it can receive the wind from the vehicle.
Furthermore, if necessary, a cooling fan is installed at the rear of the fan, and the steam introduced here is cooled by these air flows, condenses and becomes liquid cooling water again, and flows through the cooling water passage 10. The cooling water is collected in the cooling water tank 11. And further pressure reducing valve 1
2, the pressure is reduced to normal pressure, and then it is supplied to the water jacket 4 of the engine 1 again.

Next, the flow rate adjustment valve 6 and the negative pressure control valve 13 for controlling the opening degree of the flow rate adjustment valve 6 will be explained.

The flow rate regulating valve 6 is composed of a valve body 14 that opens and closes the steam passage 7, and a diaphragm-type actuator 15 that drives the valve body 14. It is separated into a chamber 17 and a negative pressure chamber 18, and a set spring 19 is disposed in the negative pressure chamber 18, and a negative pressure source, such as negative pressure in an intake manifold, is connected to this chamber through a negative pressure passage 20. configured to be installed.

On the other hand, the negative pressure control valve 13 has an atmospheric chamber 25, a negative pressure chamber 26, an atmospheric chamber 27, and a vapor pressure chamber 28, which are connected to each other via a rod 21 and have different pressure receiving areas. A valve body 29 is fixed to the upper end of the rod 21, and an atmosphere introduction port 30 is formed in the atmospheric chamber 25 facing the valve body 29. The atmosphere introduction port 30 is connected to the negative pressure passage 2.
0, and the vapor pressure chamber 28 is connected to the upper part of the water jacket 4. Further, a vent valve negative pressure in a carburetor bench valve portion (not shown) is introduced into the negative pressure chamber 26 via a negative pressure passage 33 as a signal indicating the load state of the engine. Note that 31 and 32 are set springs that bias the diaphragms 22, 23, and 24 downward and upward.

Next, the functions of the flow rate adjustment valve 6 and the negative pressure control valve 13 will be explained.

First, during normal running when the negative pressure in the vent is relatively low, the diaphragm 22 and the like move up and down in response to the steam pressure in the water jacket 4 introduced into the steam pressure chamber 28, opening and closing the atmospheric air introduction port 30. In other words, when the vapor pressure increases, the diaphragm 2
Since the atmospheric air introduction port 30 is closed by the rise of the 2nd grade, negative pressure acts on the negative pressure chamber 18 of the flow rate adjustment valve 6, and the steam passage 7 is opened. This steam passage 7
When the steam pressure inside the water jacket 4 decreases due to the opening of the diaphragm 22, etc., the diaphragm 22 moves downward, the atmosphere introduction port 30 is opened, and the negative pressure in the communication pipe 20 is weakened, so that the steam passage 7 is closed. . Therefore, by repeating this operation, the vapor pressure within the water jacket 4 is controlled to be approximately constant.

In addition, when the engine is under high load, the diaphragm 22 and the like are further pushed upward due to the increase in the negative pressure in the vent lily due to the increase in the amount of intake air, and as a result, the air intake port 30 is blocked.
opens and moves. Therefore, the amount of steam flowing out of the water jacket 4 increases as the load increases, and it is possible to cope with the increase in heat generation due to high-load operation, that is, the increase in the amount of steam generated. This prevents pressure from increasing and maintains the temperature of the engine 1 stably. That is, the opening degree of the flow rate regulating valve 6 is automatically controlled so that the vent lily negative pressure and the steam pressure always have a constant ratio.

As is clear from the above description, the internal combustion engine cooling device according to the invention is configured to store a liquid phase cooling medium in the water jacket of the engine and cool the engine by evaporating the liquid phase cooling medium. , an internal combustion engine cooling system configured to condense and liquefy the coolant vapor taken out from the engine in a condenser and to circulately supply the liquefied coolant to the water jacket of the engine again, the vapor outlet of the water jacket; A flow rate adjustment valve is installed in the engine, and the opening degree of this flow rate adjustment valve is compared using a negative pressure control valve using the negative pressure at the bench lily provided in the intake passage of the engine and the steam pressure in the water jacket as signal pressures. The structure is configured to control according to the output signal pressure obtained by adjusting and increase the opening degree according to the increase in the amount of heat generated, so if the amount of steam generated increases during high load, the steam outflow will be adjusted accordingly. The amount is regulated and the pressure inside the water jacket can be prevented from increasing. Therefore, the vaporization temperature of the cooling medium within the water jacket can be maintained constant, and stable cooling performance can always be ensured. Since it is mechanically controlled using pressure as a signal, it has a simpler structure and higher reliability than those equipped with an electrical control circuit, making it suitable for automobile engines and the like.

[Brief explanation of the drawing]

The figure is a configuration explanatory diagram schematically showing the configuration of the cooling device according to this invention. 1...Engine, 4...Water jacket,
6...Flow rate adjustment valve, 8...Compressor, 9...
Condenser, 11... Cooling water tank, 12... Pressure reducing valve, 13... Negative pressure control valve.

Claims (1)

[Scope of utility model registration request] A liquid-phase coolant is stored in the water jacket of the engine, and the engine is cooled by evaporation of the coolant, while the coolant vapor taken out from the engine is condensed and liquefied in a condenser, and the liquefied cooling medium is In an internal combustion engine cooling system configured to circulate and supply the medium back to the water jacket of the engine, a flow rate adjustment valve is provided at the steam outlet of the water jacket, and the opening degree of the flow rate adjustment valve is adjusted according to the degree of opening of the flow rate adjustment valve. Control is performed according to the output signal pressure obtained by comparing and adjusting the negative pressure control valve using the bench lily negative pressure in the bench lily section provided at the bench lily and the steam pressure in the water jacket as the signal pressure, and responding to the increase in the amount of heat generated. 1. A cooling device for an internal combustion engine, characterized in that the cooling device is configured to increase the opening degree.