JPS59194028A - Cooling device for engine - Google Patents

Abstract

PURPOSE:To improve a cooling effect, by making a compressor usable as a vacuum pump deaerating the inside of a cooling system, in case of a device which cools an engine through evaporation of a cooling medium solution and, after pressurizing and heating the vapor with the compressor, cools it with the outside air. CONSTITUTION:In time of engine starting, in order to perform deaeration of a cooling system, first solenoid valve 19 is closed and each of solenoid valves 14 and 20 is opened, while a valve 22 is opened in addition, and a compressor 8 is driven as a vacuum pump is common. If so, air inside those of a water jacket 4, a vapor passage 7, a bypass passage 13, condensers 9 and 21 and a vapor passage 23 is exhausted via the solenoid valve 20. Next, when cooling medium vapor is generated due to a temperature rise after engine starting, the solenoid valve 20 is closed while these solenoid valves 14 and 19 are opened whereby the residual air is expelled to a subcondenser 21 by dint of vapor. Afterward, with the valve 22 closed, the cooling medium is circulated, making a cooling device perform its regular cooling operation.

Description

[Detailed description of the invention] The present invention relates to a cooling device for an engine of an automobile or the like.

The present applicant has already proposed an engine cooling system that employs an evaporative cooling system in Utility Model Application No. 57-169525 and Japanese Unexamined Patent Application Publication No. 57-14312. First, this example will be described as follows.

Figures 1 and 2 show the entire configuration in detail. / is the engine 1.2 is the cylinder block, 3 is the cylinder head, G is the water jacket, J is the intake manifold, and O is the upper part of the intake manifold J. This is a steam storage chamber built in

A liquid-phase cooling medium at an appropriate level, for example, cooling water W made by adding some additive gold to water, is stored in this steam storage chamber name and the above-mentioned water jacket <z. Therefore, this cooling water W is brought to a boiling state by the engine heat and generates cooling medium vapor s2, and the heat of vaporization removes heat and completely cools each part of the engine. The coolant vapor S generated here is discharged from the vapor storage chamber 2 through the entire steam passage 7, and is introduced into a compressor or the like as a compression means.

In this compressor G, the steam passage 7 is used to adiabatically compress the steam S, and when it is discharged from the engine, the temperature and pressure are even higher, and the condenser is used as a heat dissipation liquefaction means. Send to.

The steam S introduced into the condenser is cooled by the air flow, condensed and liquefied to become cooling water W again, which is collected into the tank through the cooling water passage 10f. Furthermore, this cooling water returns to the water jacket via the pressure reducing valve 72.

/3 is the bypass passage of the compressor, and the solenoid valve in the cono bypass passage that is opened when the engine load is small /4
' is interposed. /7 is a control device that controls cooling fan/S1 compressor g, pressure reducing valve/, depending on the engine operating state.
2. Controls the entire operation of the electric valve /4/ and each glaze bar A and B described below.

The cooling fan/S is based on the signal from the vapor pressure sensor/B that detects the vapor pressure of the condenser.
The drive is controlled by 7vC. 7g is a liquid level sensor installed in the steam storage chamber X, and the pressure reducing valve /
2, the liquid level of the liquid phase cooling medium in the water jacket 4 is kept constant.

In addition, the amount of steam (garden valve /q) is operated by the output signal of the control device /7.In other words, when the engine load is small, the amount of steam generated is small, so even if the compressor g does not pressurize it, the condenser ? Since sufficient liquefaction and condensation is possible, the compressor is stopped and the solenoid valve is opened, so that the cooling medium vapor is directly sent to the condenser q through the exhaust passage 7, where it is liquefied and condensed. Ru.

In addition, the above compressor is configured to be able to be driven as a vacuum pump, and on the discharge side there is a solenoid valve as a switching valve that is opened when sending 9 volts of cooling medium to a condenser, and an electric valve for air venting. Valve 20 is connected, and during normal operation of this cooling system (C, solenoid valve /9.20 is opened by control device /7, and solenoid valve /61 is closed.4) By the way, before engine operation, steam is Atmospheric pressure air remains in the upper part of the reservoir chamber and inside the steam passages 7 and 3, and if the engine is operated at full capacity in this state, a mixture of air and coolant vapor will occur inside the cooling system. As the air becomes a gas and expands, the efficiency of heat transfer from the water jacket <z to the cooling medium> and from the refrigerant to the condenser 9 is significantly reduced. Close the valve and close the other solenoid valve.
11. ．． ．． 20 When the compressor ♂ is fully opened, the air in the cooling system can be discharged from the engine side and the condenser side through the electric θB valve -〇 by driving the compressor ♂ as a full vacuum pump. 1) Heat exchange of the condenser 9 This will improve efficiency.

Under normal engine operating conditions, the internal pressure of the water jack and condenser is completely reduced, and the heat transfer efficiency is prevented from decreasing due to air.
The desired engine cooling effect can be obtained, and the horsepower consumption of the compressor g can be completely reduced.

Note that once the air is removed, the inside of the cooling system is kept under heavy pressure while the engine is running, and no air gets mixed in.

FIG. 3 shows the difference in heat dissipation characteristics of the capacitor 9 due to the inclusion of air. According to this article, the inlet temperature of the condenser is 130°C, the partial pressure of air is 18mmHg,
The capacitor heat radiation characteristic line A when the contained air volume is 350CC is as shown in the figure, compared to the capacitor heat radiation characteristic line Bvc when the contained air volume is zero.
m/S, it can be seen that the amount of heat radiation decreases by about 25 to 26%.

Similarly, in the capacitor heat radiation characteristic line C when the partial pressure of air is 9 mm Hg and the total nitrogen content is 170 CC,
It can be seen that when the cooling air velocity is 2 m/s, the amount of heat radiation decreases by about less than 10% compared to the case where the air content is zero.

However, when using Compressor Wasabi as a full-vacuum pot to bleed air from the cooling system, it is difficult to bring the cooling system to negative pressure beyond a certain limit due to the performance of the compressor, and a small amount of air flows into the condenser 2. There was a problem that the heat exchange efficiency of the condenser 7 was hindered by remaining in the cooling system.

This idea was made to address the problems of the conventional VcN, and by using a compressor as a vacuum pump, the air from the cooling system is removed, and the steam produced by the heat generated by the engine is used to pump air into the cooling system. Exclude everything from inside 1
The purpose of the present invention is to provide an engine cooling device in which the heat dissipation characteristics of a condenser are significantly improved.

For this reason, the present invention configures the compressor of the engine cooling system so that it can be used as a vacuum pump, and provides a switching valve on the discharge side of the compressor that opens to the atmosphere when the engine is started, as well as a heat dissipation liquefaction means for the engine cooling system. In this case, the air storage means for storing all the air in the cooling system that has been expelled by the cooling medium vapor are all connected.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Below, the drawings of embodiments of the present invention will be specifically explained. Fig. 4 shows one embodiment of the same, and the same components as shown in Fig. 1 have the same reference numeral superscripted "C". In Fig. 4, 1.2/ is an air containing means. In the sub-condenser 2/, a steam passage 23 with a valve 22 is connected between the sub-condenser 2/ and the condenser 2. Between the bottom and the tank//VC, a cooling water passage 2s with a valve and 2g interposed is connected.

The operation of the sub-condenser cooling device having such a structure is as follows.

First, when venting air from the cooling system when starting the engine, close solenoid valve 7, and then close solenoid valve 4t.

As well as opening the above valve, 2.2i is opened and the compressor? is driven as a vacuum pump. By doing so, the water jacket 9, steam passage 7, bypass passage iN5/3, and condenser? , 2/ and steam passage;
2.3(7) Air in the circular portion is discharged via the solenoid valve 20. Due to this exhaustion, a small amount of air remains in each cooling system, but coolant vapor is generated due to the temperature rise after the engine starts, and at this time, the solenoid valve 20 is closed and the solenoid valve / , /9 and by opening the valve 2, - the steam passage 7, the bypass passage /
3 and the air remaining in the condenser 7 can be driven out to the sub-condenser 2/ by means of its cooling medium vapor. After that, by closing the valve 2.2, the cooling medium containing no air is completely circulated through the cooling system,
Perform all normal engine cooling operations. In this case, the air expelled to the sub-condenser 27 is transferred to the sub-condenser J/FEj17i during the engine cooling operation.
1: It is stored, but if necessary, it can be discharged to the outside using an air venting means.

Also, after the engine is stopped, by opening the valve 22.2'l, the liquefied cooling medium in the sub-condenser 27 is returned to the tank by its gravity, and is sent out to the water jacket of the engine. I can do it.

As explained above, according to the present invention, the compressor is used as a full vacuum pump, and the air in the cooling system is discharged through the switching valve provided on the discharge side of the compressor. In the early stages of operation, the cooling medium vapor is used to expel the p air, and by fully connecting the recovery means for the residual air in the fc cooling system, the heat dissipation efficiency in the condenser is improved, and as a result, engine cooling becomes more effective. The effect of this can be obtained.

[Brief explanation of drawings]

Figure 1 is a system diagram showing a conventional engine cooling system.
FIG. 2 is a partially cutaway perspective view showing only the engine portion, FIG. 3 is a heat radiation characteristic diagram of a condenser, and FIG. 4 is a system diagram of the cooling device of the present invention. /...Engine, t...Water jacket, 7.
...Steam iam, ♂...Compressor, 7...Condenser, 10...Cooling water passage, //...Tank, 7.
2...Pressure reducing valve, /1.20...Switching valve 1.2/
...Sub-condenser 1.22.2't'...Valve, 2.7...m Air passage.

Claims (1)

[Claims] A liquid-phase cooling medium is stored in the engine's water jacket, and the engine is cooled by evaporation of the liquid-phase cooling medium, while the temperature is controlled by pressurizing the cooling medium vapor by a compressor inside the engine. In an engine cooling system, a compressor is used as a vacuum pump in an engine cooling system that has a heat radiation liquefaction means that condenses and liquefies the coolant by cooling it with outside air, and circulates this liquefied cooling medium back to the engine water jacket. A switching valve is provided on the discharge side of the compressor that opens to the atmosphere when the engine starts, and the heat dissipation liquefaction means stores the air from the cooling system that is expelled by the coolant vapor at the beginning of engine operation. A cooling device for an engine, characterized in that an air storage means is connected thereto.