JPH0526257Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The present invention relates to a cooling device for an internal combustion engine that utilizes the latent heat of vaporization of a coolant, and in particular to a cooling device for an internal combustion engine that aims to improve the performance of a capacitor used in the device. Regarding equipment.

<Prior art> A boiling cooling system that supplies coolant into the water jacket of an engine and uses the latent heat of vaporization during boiling to cool the engine has a high cooling efficiency due to the large latent heat of vaporization. In addition, the steam obtained by boiling is condensed and liquefied by releasing latent heat in the condenser, resulting in high heat dissipation efficiency.

Therefore, even if the circulating amount of the coolant is reduced, sufficiently high engine cooling efficiency and condenser heat dissipation efficiency can be obtained, and the cooling device can be made considerably smaller.

Here, as an example of such a boiling cooling device, there is one shown in FIG. 2 (see Utility Model Application No. 158249/1983).

That is, in the figure, 1 is an engine, 2 is a water jacket filled mostly with liquid-phase refrigerant such as water, 3 is a condenser that cools and liquefies the refrigerant vapor from the water jacket 2, and 4 is a cooling device in the condenser 3. This is a cooling fan that supplies wind.

A water jacket 2 is formed from a cylinder block surrounding a cylinder and a combustion chamber of an engine 1 to a cylinder head, and a condenser 3 is disposed above the water jacket 2. The water jacket 2 is connected to the capacitor 3 so that the water jacket 2 forms a closed circuit for the capacitor 3.
It communicates with the inlet (upper tank) 6 of the condenser 3 through a vapor passage 5 that opens into the upper gas phase space, and the outlet (lower tank) 7 of the condenser 3 communicates with the liquid phase of the water jacket 2 through a refrigerant passage 8. will be communicated to.

A water trap 9 for separating gas and liquid is disposed in the steam passage 5, and a return passage 11 with a check valve 10 is formed between the water trap 9 and the water jacket 2. A check valve 10 is disposed in the refrigerant passage 8 so that the refrigerant level in the water jacket 2 does not drop due to the pressure of the refrigerant vapor.
2 is interposed.

On the other hand, an auxiliary tank 13 storing a predetermined amount of liquid phase refrigerant is provided. A first passage 14 (discharge passage) opens into the liquid in the auxiliary tank 13 and connects to the lower tank 7 of the condenser 3, and a first passage 14 (discharge passage) opens into the liquid in the auxiliary tank 13 (near the liquid level) and connects the water trap A second passage 15 connecting to the steam passage 5 above 9 is formed.

A check valve 16 and a solenoid valve 17 are interposed in the first passage 14, and the solenoid valve 17 opens and closes the first passage 14 as described below.

A negative pressure responsive valve 18 is installed in the second passage 5 to open the second passage 15 in response to negative pressure when the pressure in the steam passage 5 is negative. Note that the auxiliary tank 13 is communicated with the outside air through an air vent 19 at the top.

A pressure sensor 20 and a temperature sensor 21 are installed in the steam passage 5 near the water jacket 2 to detect the pressure and temperature inside the water jacket 2, and these detection signals are sent to a control circuit 22 as a control means. .

Based on these detection signals, the control circuit 22 drives the cooling fan 4 when the pressure or temperature inside the water jacket 2 becomes higher than a set value,
It will stop when it falls below the set value.

Also, based on these detection signals, the control circuit 22 controls the first control circuit during warm-up operation when the pressure and temperature inside the water jacket 2 are low, and when the pressure and temperature inside the water jacket 2 are extremely high and abnormally high temperature and pressure.
The solenoid valve 17 of the passage 14 is controlled to open.

Next, to explain the operation of this configuration, when the engine 1 is stopped, the inside of the cooling system is filled with a predetermined amount of refrigerant and air, and when the engine 1 is started, during warm-up operation, the control circuit 22 The solenoid valve 17 of the first passage 14 is opened.

As the warm-up progresses, the temperature of the refrigerant in the water jacket 2 rises due to the heat generated by the engine 1, and when the refrigerant eventually begins to boil, it generates steam while absorbing latent heat of vaporization.

This steam flows from the water jacket 2 through the steam passage 5 to the upper condenser 3.
Along with this steam, the air in the water jacket 2 and the steam passage 5 flows from the lower part 7 of the condenser 3 to the first
is discharged into the auxiliary tank 13 through a passage 14.

At this time, some steam is also discharged along with the air, but since the first passage 14 opens into the stored liquid in the auxiliary tank 13, the steam is condensed by the stored liquid and remains in the tank 13, causing the air to flow out. only is released into the atmosphere.

Thereafter, the amount of steam generated increases, the pressure within the water jacket 2 increases to a certain extent, the temperature also increases, and when warm-up is completed, the solenoid valve 17 in the first passage 14 is closed. As a result, the gas phase space within the system is filled only with steam, and in this state normal cooling operation begins.

During this normal cooling operation, steam from the water jacket 2 flows into the condenser 3 through the steam passage 5, where it is cooled and liquefied, falls through the refrigerant passage 8 by gravity, and returns to the water jacket as a liquid phase refrigerant. It is circulated and supplied into 2.

<Problems to be solved by the invention> By the way, in a boiling cooling system for an internal combustion engine, if air from the engine is not removed, air will accumulate in the condenser, reducing the cooling capacity of the condenser and causing overheating. For this reason, in the device shown in FIG. 2, air is transferred from the lower part 7 of the condenser 3 into the water jacket 2 and the steam passage 5 along with the steam to the atmosphere via the first passage 14 and the auxiliary tank 13. I try to discharge it.

However, in such a device, the air vent 3A provided in the condenser 3, that is, the connection port to the condenser 3 of the first passage 14 leading to the auxiliary tank 13, is connected to the lower tank 7 of the condenser 3, as shown in FIG. Since the opening is in the center of the lower part of one side wall, the air cannot be completely removed.

That is, since the steam flowing into the condenser 3 is filled from the inlet of the condenser 3, the air pushed by the steam will eventually collect at the end of the lower tank 7 of the condenser 3, but as described above, , the air vent 3A is opened at the center of the lower part of one side wall of the lower tank 7 of the condenser 3,
Air will not be discharged smoothly.

Therefore, in view of the conventional situation, the present invention aims to completely bleed air from the engine through the condenser to improve the capacity of the condenser.

<Means for solving the problem> For this reason, the present invention combines an engine water jacket, which is mostly filled with liquid-phase refrigerant, and a condenser, which maintains the interior in a vapor phase, with a vapor passage through which refrigerant vapor flows. In a cooling device for an internal combustion engine that communicates with a refrigerant passage for returning liquefied refrigerant to form an open circuit in which the refrigerant circulates, the condenser is disposed approximately horizontally within the lower tank, and has both ends located at both ends within the lower tank. A pipe that opens as an air vent is provided at an upper position, and a substantially intermediate portion in the longitudinal direction of the pipe is opened in the lower tank wall.

<Function> In this configuration, the steam flowing into the condenser is filled from the inlet of the condenser, so the air pushed by the steam will eventually collect at the end of the lower tank of the condenser. As shown in the figure, both ends of the pipe, which opens at the lower tank wall at approximately the middle in the longitudinal direction, are opened as air bleed ports at positions above both ends inside the lower tank, so that the air can be smoothly discharged and the air inside the engine can be removed. It can be completely removed.

<Example> Hereinafter, an example of the present invention will be described based on FIG. 1.

The structure itself of the cooling device to which this embodiment is applied is the same as that shown in FIG. 2, so in this embodiment, only the diagram showing the condenser will be described.

In FIG. 1, air vents 23A are arranged horizontally in the lower tank 27 of the condenser 23, and both ends are located above both ends in the lower tank 27.
A pipe 28 that opens as
An opening 30 is formed in the side wall of the housing.

As described above, the middle part in the longitudinal direction is the lower tank 2.
7 Both ends of the pipe 28 having an opening 30 in the wall are connected to air vents 24A at positions above both ends in the lower tank 27.
Since the steam flowing into the condenser 23 is filled from the inlet of the condenser 23, the air pushed by the steam and finally collected at the end of the lower tank 27 of the condenser 23 flows into the air vent. The air is smoothly discharged from 23A through the opening 30, making it possible to completely remove the air inside the engine.

Further, according to this configuration, since the air bleed port 24A that opens at the upper position of both ends inside the lower tank 27 is provided using the pipe 28, the pipe 28 is arranged inside the lower tank 27, It can be easily configured by just machining one opening 30 on the side wall of the lower tank 27, and there is no need to machining and opening two air vents on the side wall of the lower tank 27 itself, reducing machining work and improving manufacturability. can be achieved.

Furthermore, this configuration has the following advantages.

That is, the capacitor 23 is mounted on the vehicle with a bracket or the like, but in that case, there are cases where levelness is not obtained, although it is slightly, and the capacitor 23 is tilted so that the left or right side in FIG. 1 is at a lower level. It may become.

In this case, if air bleed ports are provided in the side wall of the lower tank 27 itself at two locations, one on the left side and the other on the right side in FIG. However, as mentioned above, the air bleed port 23A is opened at the upper position of both ends in the lower tank 27, and the opening 30 is formed in the longitudinal center of the side wall of the lower tank 27, so that air bleed is not possible. It's done smoothly.

<Effects of the invention> As explained above, according to the invention, in a cooling system for an internal combustion engine that uses latent heat of vaporization in the coolant, a substantially horizontal drop in the lower tank of a condenser that cools and liquefies refrigerant vapor from a water jacket is used. A pipe is arranged in the direction of the lower tank and has both ends opening as air vents at positions above both ends in the lower tank,
Since the approximately middle part of the pipe in the longitudinal direction is opened in the wall of the lower tank, the air that is pushed by the steam that has flowed into the condenser and eventually collects at the end of the lower tank of the condenser is smoothly discharged from the air vent through the opening. This makes it possible to completely bleed out the air inside the engine, improving the capacity of the capacitor.Moreover, it has the advantage of being easy to manufacture, and even if the capacitor is installed in an inclined position, there is no problem with air bleed. It has great practical effects.

[Brief explanation of the drawing]

Fig. 1 is a front view of a condenser showing an embodiment of a cooling system for an internal combustion engine according to the present invention, Fig. 2 is a block diagram showing the overall structure of an example of a cooling system for an internal combustion engine, and Fig. 3 is a conventional air cooling system. FIG. 3 is a front view of the condenser showing the outlet position. 23...Capacitor, 23A...Air vent,
27... lower tank, 28... pipe, 30...
Opening.

Claims (1)

[Scope of utility model registration request] A closed circuit in which the engine water jacket, which is mostly filled with liquid-phase refrigerant, and the condenser, which maintains the interior in the vapor phase, are connected through a vapor passage through which refrigerant vapor flows and a refrigerant passage where liquefied refrigerant is returned, and the refrigerant circulates. In the cooling device for an internal combustion engine, a pipe is provided which is disposed substantially horizontally in the lower tank of the condenser and has both ends opened as air vents at positions above both ends in the lower tank, 1. A cooling device for an internal combustion engine, characterized in that a substantially intermediate portion in a direction is opened in a lower tank wall.