JPS62294714A - Evaporative cooling apparatus for internal combustion engine - Google Patents

Abstract

PURPOSE:To enable a coolant level to be visually observed from a reservoir tank in an evaporative cooling apparatus, by providing an open/close means by which the upper part of a condenser is opened to the atmosphere, so that the coolant liquid level inside the condenser and that inside a reservoir tank can be made to be the same level. CONSTITUTION:The upper space of a reservoir tank 25 having a volume nearly equal to the inner volume of a condenser 3 is opened to the atmosphere via an atmosphere communicating passage 26, and a detachable cap 27 for filling coolant is provided on it. Further, the reservoir tank is connected to the lower tank 21 of the condenser 3 via the first coolant circulating passage 28, and is connected to a water jacket 2 via the second coolant circulating passage 29 in which a coolant feed pump 4 is interposed. On the connecting pipe 8 communicating the vapor outlet 7 of the water jacket 2 with the upper inlet 3a of the condenser 3, a cap 10 by which the upper part of the condenser 3 is opened to the atmosphere when the level of coolant is to be checked is detachably provided.

Description

[Detailed Description of the Invention] Industrial Application Field This invention is an internal combustion engine cooling system that stores liquid phase refrigerant up to a predetermined level in a water jacket and cools various parts of the internal combustion engine by boiling and vaporizing the liquid phase refrigerant. The present invention relates to devices, and particularly relates to an improvement of a boiling cooling device of the type in which the pressure inside the system is maintained at approximately atmospheric pressure via a reservoir tank opened to the atmosphere.

Conventional technology This application forms a closed-loop refrigerant circulation system mainly consisting of a water jacket, a condenser, and a refrigerant supply pump, and the refrigerant vapor generated in the water jacket is guided to the condenser and condensed. The refrigerant supply pump is activated based on the detection by the surface sensor, and a boiling cooling device is proposed (2) in which the refrigerant is supplied to the water jacket again. (Japanese Publication No. 60-36715, etc.). In this system, the cold sister circulation r:i system is kept in a closed state, and for example, by controlling the cooling fan based on the temperature rise, the system 1a CJ"
Where is it? The temperature is maintained at l.

In response to this, the present applicant has also proposed a boiling cooling device that is open to the atmosphere and is extremely simplified without performing complicated temperature control (Japanese Patent Application No. 147814/1984, etc.). In this system, the reservoir tank, which is open to the atmosphere, and the condenser lower tank are always in communication, and the system consisting of the condenser, water jacket, etc. is maintained at approximately atmospheric pressure. Since the refrigerant can move freely, the liquid level inside the condenser naturally moves up and down so that the amount of heat dissipated by the condenser and the amount of heat generated by the engine are in balance, and the temperature within the system can be kept approximately constant.

Problems to be Solved by the Invention In the above-mentioned atmospheric cooling type evaporative cooling device, there is not enough liquid refrigerant in the entire device to fill at least the portion of the water jacket below a predetermined level and the entire condenser. However, after warm-up is complete, the liquid phase refrigerant moves between the reservoir tank and the condenser as described above, so it is not possible to know if there is a refrigerant shortage by looking at the liquid level in the reservoir tank. Can not. Part 1. Even if the engine is cold, if there is air remaining in the condenser, the amount of liquid phase refrigerant remaining in the reservoir tank will be different, so it is difficult to know if there is a shortage of refrigerant. be.

Therefore, especially if the reservoir tank is downsized and the amount of refrigerant in the device is set to a relatively small amount, evaporation of the refrigerant during long-term operation will cause a shortage of refrigerant, making it impossible to maintain the liquid level in the water jacket at the specified level. There is a risk.

Means for Solving the Problems In order to solve the above problems, the present invention provides an opening/closing means for opening the upper part of the capacitor to the atmosphere.
The present invention is characterized in that a reference level for determining refrigerant shortage is set in the reservoir tank, corresponding to the minimum amount of refrigerant when the refrigerant liquid level in the water jacket is at a predetermined level.

If the opening/closing means is opened to open the upper part of the condenser to the atmosphere when the operating engine is stopped or cold immediately after starting, the refrigerant liquid level in the condenser and the refrigerant liquid level in the reservoir tank will be at the same height. . Therefore, the liquid level position in the reservoir tank at this time is compared with the reference level by visual inspection or by checking the liquid level.1. - If it is below that level, it is determined that there is a refrigerant shortage.

Embodiment - FIG. 1 shows an embodiment of the boiling cooling device according to the present invention. In the figure, 1 is an internal combustion engine equipped with a water jacket 2, and 3 is an internal combustion engine equipped with a water jacket 2. Condenser 1 indicates an electric refrigerant supply pump.

The water jacket 2 is formed over both the cylinder block 5 and the cylinder head 60 so as to surround the outer periphery of the cylinder and combustion chamber of the internal combustion engine 1, and the upper part, which is normally a gas phase space, is located between each cylinder. They are in communication with each other, and a steam ratio lower is provided at an appropriate position above them. This steam ratio lower has a connecting pipe 8 and a steam passage, and the connecting pipe 8 has an opening/closing means and 1 to 1.
A C cap IO is removably provided. Also, at a predetermined level of the water jacket 2, specifically at a height approximately in the middle on the cylinder head side, it can be turned on or off depending on the presence or absence of liquid phase refrigerant. A liquid level sensor 1) using, for example, a reed switch that emits an F-fold signal is disposed, and a first temperature sensor 12 consisting of a thermistor or the like is disposed below this, that is, at a position normally submerged in the liquid phase refrigerant. has been done.

Further, reference numeral 13 denotes a heater for heating the passenger compartment 15 which is connected to the water jacket 2 through a heater passage 14, and is operated in conjunction with a heater switch (not shown) on the downstream side thereof. The heater pump 16 is protected from mosquitoes. 17 is the discharge i1i of the heater pump 16! Branching from I1. This is a refrigerant mixing passage whose tip is connected to the connecting pipe 8, and has the function of sending a small amount of liquid phase refrigerant to the condenser 3 in order to prevent uneven distribution of antifreeze components in the refrigerant during winter, that is, when the heater is in use. There is. In this refrigerant mixing passage 17, a normally open ruminal valve 18 is connected, and a cold W conductor in one chamber is connected.

The condenser 3 is composed of an upper tank 19 having the population 3a, a core section mainly consisting of fine tubes along the vertical direction, and a lower tank 21 that temporarily stores the liquefied refrigerant condensed by the core section. It is installed in a position such as the front of the vehicle that receives the wind from the vehicle, and is further equipped with an electric cooling fan η for forced cooling on the front or back side. Further, a second temperature sensor n consisting of a nermistor or the like that detects the temperature of the refrigerant inside the lower tank 21 is disposed, and the temperature detected by the second temperature sensor n and the temperature detected by the first temperature sensor 12 are arranged in the lower tank 21. The cooling fan n is configured to operate when the difference between the two, that is, the degree of supercooling of the condenser 3 becomes less than a predetermined value.

Reference numeral 5 denotes a reservoir tank having a volume approximately equal to the internal volume of the condenser 3 (2), the upper space of which is open to the atmosphere via an atmosphere communication passage 26, and is detachable for refrigerant injection. It has a first cap r, and a first cap r.
The second refrigerant circulation passage 29 is connected to the lower tank 21 through the refrigerant circulation passage 2+, and is connected to the water jacket 2 through a second refrigerant circulation passage 29 equipped with a refrigerant supply pump 4. After the boiling starts, the liquid phase refrigerant moves freely between the condenser 3 and the reservoir tank 5 so that they are pressure-coupled, and as a result, the condenser 3
The heat dissipation capacity of the engine and the amount of heat generated by the engine are always in an equilibrium state, and the engine temperature is kept approximately constant at the boiling point of the refrigerant at atmospheric pressure. When the refrigerant liquid level in the water jacket 2 drops below the level set by the liquid level sensor 1) due to boiling, the refrigerant supply pump 4 is activated to replenish the liquid phase refrigerant from the reservoir tank 5 to the water jacket 2. be. Same, Canada is from water jacket 2 to reservoir tank 5
This is a check valve that prevents the refrigerant from flowing backwards. Further, the atmospheric communication passage 26 is equipped with a normally open second solenoid valve 31, which closes only when the degree of supercooling in the condenser 3 is extremely reduced to increase the heat dissipation capacity. The inside of the reservoir tank normally communicates with the atmosphere [7].

The reservoir tank 5 is made of transparent or semi-transparent resin so that the internal liquid level can be visually checked, and a reference level, that is, an appropriate amount of refrigerant is shown on the ψU surface of the reservoir tank 5, as shown in FIG. A lower limit line 32 indicating the lower limit of , and an upper limit line 33 indicating the upper limit of the appropriate amount of refrigerant are drawn. Here, the minimum refrigerant amount corresponding to the lower limit line: 32 is determined by adding the volume of the lower tank 21 of the condenser 3 and the core part to the volume below the set level of the liquid level sensor 1) in the water jacket 2. , and is the amount obtained by subtracting about 1/2 of the volume of the upper tank 19 from this, and the maximum amount of refrigerant corresponding to the upper limit line 33 is similarly determined by subtracting about 1/2 of the volume of the upper tank 19 from the lower tank 21 and the volume of the core part, and further 1/'2 of the volume of the upper tank 19. This is the amount in which Ii degree is added. The lower limit line, 32, and the upper limit line; -3, seal this minimum amount of refrigerant t1' or the maximum amount of refrigerant in the device, maintain the refrigerant liquid level in the water jacket 2 at the above set level, and open the upper part of the condenser 3 to the atmosphere. Then, the capacitor 3 and the reservoir tank part ・P'・JA+,=
1)・ri”=iz・?・/rfr1hot・i&・ko1
+z7+,1),...1,1ra1,,4rko1. “Ha I
IJN, j/7 It is set corresponding to the liquid level position in the tank.

Therefore, in the above configuration, in order for the driver to check whether the amount of refrigerant is excessive or insufficient, with the ignition key turned on, open the cap lO as shown in FIG. It is best to visually check whether it is within the range between the lower limit line 3z and the upper limit line 33. That is, when the ignition key is turned on, a series of controls is started, and the liquid level of the refrigerant in the water jacket 2 is maintained at the level set in the sensor 1), and when the cap 10 is opened, the inside of the condenser 3 and the reservoir tank are Since the liquid level position within the reservoir tank is equal, it is possible to determine whether there is an excess or deficiency of liquid phase refrigerant in the entire device based on the liquid level position within the reservoir tank. If there is a shortage of refrigerant, refrigerant is replenished into the reservoir tank from the bottom of the cap. In addition, in order to cope with the case where the refrigerant is refilled too much, the reservoir tank 25
It is preferable to provide a drain (not shown) in the F section. This inspection of the amount of refrigerant can be performed even after the engine is started, but if boiling occurs within the water jacket 2, the apparent volume increases, so it is necessary to check the amount immediately after the engine is started.

Incidentally, the reservoir tank 5 may be made opaque 2 and a transparent tube may be provided on its side surface to indicate the liquid level position.

Next, in the embodiment shown in FIG. 3, the refrigerant shortage is automatically detected, and a normally closed third magnetic valve 35 is installed as an opening/closing means near the upper tank 19 of the condenser 3.
In addition, a liquid level sensor is provided at the reference level of the reservoir tank 60. That is, immediately after the engine is started, the control device 37 controls the third solenoid valve) and the second M! of the reservoir tank 5. If the magnetic valve 31 is opened and the refrigerant level in the reservoir tank 5 is below the level detected by the liquid level sensor, a warning lamp will be activated to alert the driver to the refrigerant level. This encourages the injection of

Further, in the embodiment shown in FIG. 4, the first solenoid valve 18 is
'' and a three-way electromagnetic valve that can be switched to ``flow path B'' to configure the opening/closing means without increasing the number of electromagnetic valves.

The embodiment shown in FIG. 3 or 4 can also be combined with the visual embodiment shown in FIG. 1.

Effects of the Invention As is clear from the above description, according to the present invention, it is possible to reliably and easily detect a lack of refrigerant in the device visually or by using a liquid level sensor or the like. Therefore, there is no need to reserve a large amount of refrigerant with an excessive allowance in the apparatus, and problems such as a drop in the liquid level in the water jacket due to insufficient refrigerant do not occur.

[Brief explanation of drawings]

FIG. 1 is a configuration explanatory diagram showing one embodiment of the present invention, FIG. 2 is a sectional view showing only the reservoir tank, and WJ3 and FIG. 4 are configuration explanatory diagrams showing other embodiments of the present invention. be. 1... Internal combustion engine, 2... Water jacket, 3...
...Condenser, 4...Refrigerant supply pump, IO...
Cap, 1)...Liquid level sensor, 21...Lower tank, 6...Reservoir tank, 32...Lower limit line, :3
3-... Upper limit line, 35... Third solenoid valve, 36...
Liquid level sensor 〇 2 people outside Fig. 1 2 ・Waokun゛

Claims (1)

[Claims] (1) A water jacket in which liquid phase refrigerant is stored up to a predetermined level determined by a liquid level sensor, refrigerant vapor generated in this water jacket is introduced, and condensed liquid phase refrigerant is stored in a lower tank at the bottom. a refrigerant supply pump that operates based on a detection signal from the liquid level sensor and replenishes the water jacket with liquid phase refrigerant condensed in the condenser, and a reservoir tank that is constantly in communication with the lower tank and is open to the atmosphere. In the evaporative cooling system for an internal combustion engine, the apparatus is provided with an opening/closing means for opening the upper part of the condenser to the atmosphere, and a means for opening and closing the upper part of the condenser to the atmosphere, and a means for opening and closing the upper part of the condenser to the atmosphere, and a means for opening and closing the upper part of the condenser to the atmosphere, and a means for opening and closing the upper part of the condenser to the atmosphere; A boiling cooling device for an internal combustion engine, characterized in that a reference level is correspondingly set for determining refrigerant shortage.