JPS6183439A - Evaporative cooling device for internal-combustion engine - Google Patents

Abstract

PURPOSE:To make temperature inside the system follow up the desired temperature as well as to aim at an accuracy improvement in temperature control, by controlling each liquid level of a water jacket and a condenser according to the outside temperature. CONSTITUTION:A solenoid valve 35 is installed in passages 35 and 43 connecting a reservoir tank 41 to a water jacket 22, and another solenoid valve 44 is installed in a passage 36 connecting the tank 41 to a condenser 23. In addition, at this water jacket 22, there are provided with a liquid level sensor 52 and a temperature sensor 53 as well as a suction temperature sensor 56 detecting the outside temperature is installed there. A control unit 51 inputs each signal out of these sensors and compares refrigerant desired temperature with the detection temperature whereby it controls these solenoid valves 35 and 44 to be set in a direction eliminating the deviation and adjusts the liquid level, while in time of the outside temperature being low, it holds down refrigerant intake by these solenoid valves 35 and 44 to below the fixed value, checking a rise in the liquid level.

Description

[Detailed Description of the Invention] Industrial Application Field This invention stores a refrigerant in a water jacket, cools an internal combustion engine by boiling and vaporizing the refrigerant, and condenses the generated refrigerant vapor in a condenser. The present invention relates to an evaporative cooling device for an internal combustion engine that is reused.

Conventional Technology As is well known, the temperature of an internal combustion engine not only directly affects the engine's thermal efficiency, filling motion, and anti-knock performance, but also affects friction loss due to oil viscosity, and affects the engine's fuel consumption rate, maximum output, and so on. This is a factor that affects the level of noise. However, in conventional general water cooling equipment,
Excessive cooling during warm-up is only prevented by switching the flow paths in the thermostat, and there is no temperature control at all. In addition, the electric fan's 0N-OF
Even if you try to perform full temperature control from the FK, a large amount of cooling water is circulating in the cooling system, and you have to wait for the entire temperature to change. Therefore, the temperature can be set variably depending on the operating conditions such as load and rotation speed. It is completely impossible to follow the target temperature with good response.
E-level temperature control cannot be achieved in parallel.

On the other hand, in contrast to the above-mentioned cooling devices that utilize simple temperature changes in cooling water, various cooling devices that utilize phase changes between liquid and gas phases of refrigerant (cooling water) have also been proposed (for example, the Publication No. 57-57608.

JP-A-57-62912, etc.). This basically boils the liquid phase refrigerant stored in the water jacket and transfers the generated vapor to an external condenser. After the heat is radiated and liquefied through a radiator, the heat is liquefied and then circulated back into the water jacket.This structure allows the temperature of each part of the water jacket to be maintained uniformly at the refrigerant boiling point, and dramatically increases the heat exchange efficiency in the condenser. Benefits that can be improved have been pointed out. When utilizing phase change in this way, the boiling point of the liquid phase refrigerant can be changed arbitrarily and rapidly by variably controlling the pressure inside the water jacket, so it is possible to change the boiling point of the liquid phase refrigerant arbitrarily and quickly. There is a possibility that temperature control with good performance can be realized.

However, in conventional cooling systems of this type, the temperature immediately changes depending on the system pressure as described above.
Rather, it was thought to be a major drawback that made it difficult to put the cooling device into practical use.

In other words, if the cooling system is sealed with a water jacket, condenser, etc., when applied to an automobile engine, for example, the amount of heat generated by the engine will vary over a wide range, and the heat dissipation capacity of the highly efficient condenser will vary depending on the wind flow when the vehicle is running. Since it is mostly controlled by the size of
It is not possible to control the arrangement of condensers by slightly changing the amount of air blown by the cooling fan to the condenser.

Therefore, as seen in the above-mentioned Japanese Patent Publication No. 57-57608 and Japanese Patent Application Laid-Open No. 57-62912, conventional devices have a substantially non-sealed structure by partially communicating the inside of the cooling system with the atmosphere. The boiling point of the refrigerant is fixedly maintained at atmospheric pressure, and as a result, temperature control according to the operating conditions as described above has not been realized.

Problems to be Solved by the Invention In order to realize variable temperature control as described above, the present applicant has created a part of the inside of the condenser as a liquid-phase refrigerant region, and by controlling the liquid level position, We previously proposed a boiling cooling device configured to change the pressure within the closed cooling system by variable control of the heat dissipation area (%Gan Sho 59-10015).
No. 6 5% Application No. 59-140378, etc.). This invention is
This is a further development of the boiling cooling bag (! The purpose of this invention is to avoid continuation of wasteful liquid phase refrigerant introduction operation and damage to the condenser due to excessive forced refrigerant introduction, which may occur if the refrigerant is not used.

Means to solve problems FIG. 1 is a functional block diagram showing the configuration of the present invention.

The water jacket 1 of the engine has a structure in which liquid phase refrigerant is stored, and together with the condenser 2, is kept in a sealed state from the outside air. The condenser 2 is connected to the water jacket 1 so that the refrigerant vapor generated in the water jacket 1 is introduced from a relatively upper portion, and from the lower portion Ii! The structure is such that the compressed liquid phase refrigerant is taken out. Further, a reservoir tank 6 which is open to the atmosphere is provided outside the water jacket 1 and the like sealed in this manner, and an appropriate amount of liquid phase refrigerant is stored inside the reservoir tank 6.

The refrigerant supply means 4 supplies liquid phase refrigerant to the water jacket 1 from the lower part of the condenser 2 or the reservoir tank 6, and is composed of, for example, an electric pump.

The refrigerant introducing means 5 is for introducing liquid refrigerant into the reservoir tank 3 or the lacondenser 2 in order to increase the liquid level of the liquid refrigerant in the condenser 2, and the refrigerant discharging means 6 is for introducing the liquid refrigerant into the reservoir tank 3 or the lacondenser 2 in order to increase the liquid level of the liquid refrigerant in the condenser 2. In contrast, the liquid phase refrigerant is completely discharged from the condenser 2 into the reservoir 3.

The refrigerant introducing means 5 and the refrigerant discharging means 6 can be constructed from, for example, electric pumps, but a single pump capable of pumping in both forward and reverse directions may be used in common without providing respective pumps, or a single pump capable of pumping in both forward and reverse directions may be used. It is also possible to adopt a configuration in which a plurality of electromagnetic valves are used to appropriately form the flow paths on the suction side and the discharge side of a single pump that can pump in only one direction. Furthermore, a configuration in which a single pump is shared including the refrigerant supply means 4 is also possible.

On the other hand, for the water jacket 1, a liquid level detection means 7 for detecting the liquid level position of the liquid phase refrigerant stored therein and a temperature detection means 8 for detecting the temperature of the liquid phase refrigerant are used. It is being The temperature detection means 8 may not only directly detect the liquid phase refrigerant, but may also indirectly detect the temperature at an appropriate position in the engine, the pressure in the gas phase refrigerant area above the water jacket 1, etc. Also good.

The water jacket side liquid level control means 9 controls the refrigerant supply means 4 based on the detection by the liquid level detection means 7, and as a result of this control, the refrigerant reduced by boiling and vaporization in the water jacket 1 is reduced. The refrigerant is replenished by supplying refrigerant from the condenser 2 or the reservoir tank 6, and the liquid level is always kept substantially constant.

The target setting means 10 sets the optimum target temperature by inputting various operating condition signals such as the rotational speed of the load 9, and the capacitor side liquid level control means 11 controls the target temperature and the temperature detected by the temperature detection means 8. The temperature is compared with the temperature, and the refrigerant introducing means 5 and the refrigerant discharging means 6 are controlled in order to match the two.

Further, the outside temperature detection means 12 for detecting the outside temperature is constituted by an independent temperature sensor or other intake temperature sensor. The liquid level rise canceling means 16 cancels the operation of the refrigerant introduction means 5 within a certain limit, for example, for a certain period of time and at a certain thickness, at a predetermined low temperature, based on the detected outside temperature.

The heat exchange efficiency of the condenser 2 changes significantly depending on whether the inside of the condenser 2 is filled with liquid-phase refrigerant or gas-phase refrigerant. , only the region of the gas phase refrigerant becomes the substantial heat dissipation area. Therefore, by controlling the height of the liquid level, the heat dissipation ability can be controlled arbitrarily and over a wide range.

As mentioned above, since the water jacket 1 etc. are in a sealed state, the amount of refrigerant condensed is determined by the heat dissipation capacity of the condenser 2, and the amount of steam generated due to the amount of heat generated on the water jacket 1 side. If the balance is disrupted, the internal pressure will immediately fluctuate, causing a change in the boiling point of the refrigerant, and the temperature within the water jacket 1 will quickly rise or fall.

That is, when the detected temperature is above the target temperature, the liquid phase refrigerant is discharged from the condenser 2 by the operation of the refrigerant discharge means 6 to expand the heat dissipation capacity, and when the detected temperature is below the target temperature, The liquid phase refrigerant is introduced into the condenser 2 by the operation of the refrigerant introduction means 5 to suppress the heat dissipation ability, thereby realizing temperature control with high precision and good response.

On the other hand, if the outside temperature is too low, the operation of the refrigerant introducing means 5 is canceled within a certain limit. This is because when the outside temperature is low and the engine is under low load, the system temperature may not recover to the target temperature even if condenser 2 is completely filled with liquid phase refrigerant. Excessive pressure rise is prevented by operation and forced introduction of liquid phase refrigerant.

Embodiment FIG. 2 shows an embodiment of the boiling cooling device according to the present invention, in which 21 is a water jacket 22.
26 is a condenser for condensing gas phase refrigerant, and 24 is an electric refrigerant supply pump.

The water jacket 22 is formed over both the cylinder block 25 and the norinda head 26 so as to surround the cylinder and the outer periphery of the combustion chamber of the internal combustion engine 21, and the upper part, which is normally a gas phase space, is The cylinders communicate with each other, and a steam outlet 27 is provided at an appropriate position above the cylinders. This steam outlet 27 communicates with the upper inlet 23a of the condenser 26 via a connecting pipe 28 and a steam passage 29, and the connecting pipe 28 has a discharge pipe attachment part 28a which is the top of the refrigerant circulation system. It is formed in a shape that rises upward, and its upper opening is sealed by Cab Pro 0.

The condenser 26 is composed of the above-mentioned population 23af: the above-mentioned aperture filter 1, a core section filtration 2 mainly consisting of fine tubes in the vertical direction, and a lower tank 66 that temporarily stores the liquefied refrigerant RIm in the core section 32. The cooling fan 34 is installed at a position such as the front of the vehicle that receives wind from the vehicle running, and is further provided with an electric cooling fan 34 for forced cooling on the front or back side. Further, the lower tank 66 has one end connected to a refrigerant circulation passage 65 at a relatively lower portion thereof, and one end of a first auxiliary refrigerant passage 66 to an upper portion thereof. The above refrigerant circulation passage 6
5 has the other end connected to the refrigerant inlet 221L provided on the cylinder hept 26 side of the water jacket 22, and is equipped with a three-way second electromagnetic valve 67 in its passage, and this second electromagnetic valve The refrigerant supply pump 24 is interposed between the refrigerant supply pump 67 and the lower tank 36.

41 is the water jacket 22 and the capacitor 26
This is a reservoir tank provided outside the tightly sealed system mainly consisting of a reservoir tank, which is open to the atmosphere through a cap 42 having a ventilation VIA function, and is installed at a position approximately at the same height as the water jacket 22. The first auxiliary refrigerant passage 66 and the second auxiliary refrigerant passage 46 are connected to the bottom thereof. The first auxiliary refrigerant passage 66
is provided with a normally open third solenoid valve 44 in its passage, and the second auxiliary refrigerant passage 46 is connected to a refrigerant circulation passage 65 via a second solenoid valve 67. The second electromagnetic valve 67 shuts off the refrigerant circulation passage 35 in the excited state and establishes communication between the reservoir tank 41 and the lower tank 36 through the flow path A), and in the de-energized state, the second auxiliary refrigerant passage 431!
! ! ! The refrigerant circulation passage 65 is placed in a communicating state (flow path B) by being disconnected.

The refrigerant supply pump 24 is one that can pump the liquid phase refrigerant in both forward and reverse directions, and if the refrigerant supply pump 24 is driven in the forward direction in the state of the flow path A, the refrigerant is transferred from the lower tank 63 to the reservoir. The liquid phase refrigerant can be forcibly discharged to the tank 41, and the reservoir tank 41 can be discharged by driving in the opposite direction.
The liquid phase refrigerant can be forcibly introduced from the lower tank 63 to the lower tank 63, and if the refrigerant supply pump 24t is driven in the forward direction in the state of the flow path B, the liquid phase refrigerant can be circulated and supplied from the lower tank 66 to the water jacket 22.

On the other hand, the discharge pipe attachment part 28 which is the top of the above-mentioned closed system
8 includes an air discharge passage 45 for discharging air within the system.
is connected, and the tip of the air exhaust passage 45 opens into the reservoir tank 41 to collect the liquid phase refrigerant that overflows at the same time as the air is exhausted. A normally closed first solenoid valve 46 is interposed in the air exhaust passage 45.

The electromagnetic valves 46, 37, 44, the refrigerant supply pump 24, and the cooling fan 64 are driven and controlled by a control device 51 using a so-called microcomputer system. The first
The control described below is performed based on detection signals from the liquid level sensor 52, the temperature sensor 53, the second liquid level sensor 54 provided in the lower tank 63, the negative pressure switch 55 provided at the top of the circulation system, and the outside temperature sensor 56. .

Here, the above 1. The second liquid level sensors 52 and 54 are, for example, float type sensors using reed switches, which detect whether the refrigerant liquid level has reached a set level in an on/off manner. The detection level of the liquid level sensor 52 is set at a height approximately midway between the cylinder head 26, and the detection level of the second liquid level sensor 54 is set at a height slightly above the opening of the first auxiliary refrigerant passage 66. It is set at a height of . Further, the temperature sensor 56 is made of, for example, a thermistor, and is provided at a position slightly below the first liquid level sensor 52 and immersed into the liquid phase refrigerant to detect the temperature of the refrigerant within the water jacket 22. are doing. Negative Pressure Sinogu・55 uses a diaphragm that responds to the differential pressure between atmospheric pressure and system pressure, and the system is under negative pressure relative to the atmospheric pressure in the operating environment, regardless of whether it is used in highlands or lowlands. It detects whether or not there is, specifically -30
Yes, the working pressure is set at about Kg to -50 II Hg. Further, the outside temperature sensor 56 is provided, for example, at a position downstream of the air cleaner, and also serves as an intake temperature sensor for controlling the air-fuel ratio.

Note that various sensors for detecting other engine operating conditions are not shown.

FIG. 3 to FIG. 12 are flowcharts showing the contents of the control executed in the control bag a51.
This will be explained along the flow from starting to stopping the engine. In addition, in the figure, the first to third electric valves 46, 37, and 44 are respectively "
They are abbreviated as "electrode valve ■", "electrode valve ■", etc., and the liquid level inside the water jacket 22 is abbreviated as rclH internal liquid level J.

FIG. 3 is a flowchart showing an overview of the control. When the control starts when the engine starts (ignition key is turned ON), the initialization process in step 1 (see FIG. 5) is performed, and then the start starts at the initial stage. It is determined whether it is a start or a restart, specifically whether the temperature detected by the temperature sensor 56 is higher than a predetermined temperature (for example, 45° C.) (step 2). If the temperature is below a predetermined temperature, that is, the initial startup is in an unwarmed state, the process goes through air exhaust control in step 3 and then proceeds to warm-up control in step 4, and thereafter the temperature is controlled.

Step 5 to step 100 control loop such as liquid level control etc. are repeated until the key is turned off. On the other hand, if the temperature is higher than the predetermined temperature in step 2, that is, at the time of restart, air intrusion over time is not considered, so air exhaust control (step 6) is omitted.

Also, if a key OFF signal is input during the control,
The interrupt control routine shown in FIG. 4 is executed, and the key OF
After a certain process by the F control (step 11), the power is turned off and the series of controls ends.

FIG. 6 shows a flowchart of StepPro's air discharge control. Note that when the engine is started, the inside of the system is usually almost filled with liquid-phase refrigerant (for example, a mixture of water and antifreeze), and the reservoir tank 41 contains more liquid than can completely fill the inside of the system. Phase refrigerant is stored. In the air discharge control, air is discharged from this state by completely filling the system with water. First, in step 61, the 11th! The magnetic valve 46 is “open”, the second magnetic valve 37 is “flow path A”, the third i1! The magnetic valves 44 are controlled to be "closed," and in step 62, the refrigerant supply pump 24 is started to be driven in the opposite direction. Thereby, the liquid phase refrigerant in the reservoir tank 41 is introduced into the system via the second auxiliary refrigerant passage 43t.

This is done in step 3 for a predetermined period of time, specifically within the system 't.
- It continues for several seconds to several tens of seconds, which is set in advance on a software timer, which is sufficient to fill the water with water.

Therefore, the air remaining in the system is collected in the upper part of the system, and then is forcibly discharged to the side of the reservoir tank 41 outside the system via the air discharge passage 45. Then, when a predetermined period of time has elapsed, the refrigerant supply pump 24t is turned off (step 34).
) and clear the timer ■ (Steasive 35)
L. Proceed to warm-up control (Step 4) shown in FIG.

When warm-up control begins, the inside of the condenser is naturally filled with liquid-phase refrigerant, so the heat dissipation capacity of the condenser 26 is suppressed to an extremely low level, and as a result, the temperature of the refrigerant inside the water jacket 22 quickly decreases. and then boiling begins. The warm-up control basically involves waiting while the lower tank 63 and the reservoir tank 41 are kept in communication (steady 41) until the refrigerant temperature in the water jacket 22 rises to the target temperature, and step 46 is performed.
Then, calculate the ratio a between the actual detected temperature and the set temperature, and when the detected temperature reaches the set temperature 10 zO ℃ (α,), the system is sealed (step 45) and this control is terminated. do. The above-mentioned set temperature (Steasive 42) is optimally set at any time depending on the operating conditions such as engine load and rotational speed, and is set, for example, within the range of 80 to 110 degrees Celsius (hereinafter referred to as Stesive 51). The same applies to steps 67 and 74).

On the other hand, during this warm-up control, the inside of the system is open to atmospheric pressure, so if the set temperature exceeds approximately 100°C, the liquid phase refrigerant in the system will flow into the reservoir tank 41 due to the generated vapor pressure. As a result of being pushed out, the liquid level in the water jacket 22 and the liquid level in the lower tank 66 decreases excessively before the refrigerant temperature reaches the set temperature. To deal with this,
When either the liquid level falls below the set level of the first liquid level sensor 52 or the second liquid level sensor 54 (step 4
If No in step 4), immediately seal the system internally (step 4).
5) and ends this control.

After the warm-up control is completed, the control loop from Step 5 to Step 100 is repeated as described above, but this control loop includes Step 5, which performs minute control by turning on and off the cooling fan 64. The water jacket 2
The liquid level control in Step 6 (Fig. 9) to keep the liquid level in Step 2 above the set level, and the actual heat dissipation area is expanded or reduced if the detected temperature deviates relatively far from the target set temperature. Stesive 9 water level reduction control in the condenser (8
(Fig. 10) and step 10 (Fig. 11) to increase the water level in the condenser.

First, as mentioned above, we will explain the case where this control loop is entered in a state in which the detected temperature in the warm-up control (Fig. 7) is "set temperature value '2..O ℃ (α,)". Then, step 52 in FIG. At step 53, the cooling fan 3j1 is turned ON, and since the upper limit temperature at step 7 (set temperature +2.0° C. (αs)) has already been exceeded, the water level reduction control in the condenser shown in FIG. 10 is immediately started.

This condenser water level lowering control is performed by supplying the liquid phase refrigerant in the condenser 26 to the reservoir tank 4 by the refrigerant supply bonder 24.
Step 61゜Step Pro 2),
The liquid level inside the capacitor 23 is lowered to increase the heat dissipation ability, and its discharge is performed when the detected temperature is "set temperature + 1.0".
The process continues until the temperature decreases to .degree. C. (.alpha., )" (Step Pro 7, Step 68), and finally the system is closed (Step 69) and ends. The above end temperature is a condition that depends only on the cooling fan 64, which is the upper limit temperature [set temperature zO ℃ (α, )] and the lower limit temperature [set temperature -
4.0℃ (α,)] and slightly higher than the set temperature.
This takes into consideration the responsiveness of temperature changes.

Also, even during the refrigerant discharge, the refrigerant continues to boil in the water jacket 22, so the liquid level gradually decreases, but if the liquid level on the water jacket side falls below the set level, The second tfB valve 37 is temporarily switched to "flow path B" to replenish liquid phase refrigerant from the condenser 26 to the water jacket 22 (steps 6 to 65),
The level set by the first liquid level sensor 52 is maintained. In the unlikely event that even if the liquid level in the condenser 26 is lowered to the maximum, insufficient heat dissipation capacity cannot be avoided and the liquid level falls to the level set by the second liquid level sensor 54. , this control is immediately terminated to prevent steam from leaking out (Step Pro 6). Also, for the same reason, when the liquid level in the condenser 26 is below the set level of the second liquid level sensor 54 in the stem lug 8, the water level reduction control in the condenser is not performed.

On the other hand, as described above, the liquid level in the condenser 26 is appropriately controlled, the amount of heat generated by the engine and the amount of heat dissipated from the condenser 26 are approximately balanced below the boiling point, and the system is tightly closed at Δ. The fan control (step 6) shown in Figure 8 and the liquid level control (step 6) shown in Figure 9 are repeated. Set temperature + 0.5℃ (α,)” and “
Set temperature -0.5℃ (between αt+J (step 52)
Only the cooling fan 64 is controlled to turn on and off (steps 56 and 54). In addition, in the above liquid level control, when the liquid level in the water jacket 22 falls below a set level, liquid phase refrigerant is supplied from inside the condenser 23 to the quarter jacket 22 to maintain the liquid level at the set level ( Steps 55-57).

In addition, if the system temperature falls below the lower limit temperature in step 7 [set temperature -4.0°C (α4)] due to disturbances such as an increase in vehicle running wind or changes in the set temperature itself due to changes in operating conditions, The control for increasing the water level in the condenser shown in FIG. This is a control that suppresses the heat dissipation ability.In this embodiment, when introducing the liquid phase refrigerant, forced introduction by driving the refrigerant supply pump 24 in the reverse direction and refrigerant introduction using the pressure difference inside and outside the system are performed. In other words, when the system is under negative pressure (step 71) due to the signal from the negative pressure switch 55, the third
is set to "open" (step 72), and the first auxiliary refrigerant passage 36 is opened.
The refrigerant is introduced using the pressure difference inside and outside the system. When this refrigerant is introduced, the detected temperature is [set temperature - 10℃ (α6)
'' (steps 74 and 75), and finally closes the tffi in the system (step 84) to end the process.

The above-mentioned end temperature also takes into account the responsiveness of temperature change to the rise in the liquid level. If the liquid phase refrigerant in the water cage I 22 becomes insufficient during this refrigerant introduction, the refrigerant is replenished by the refrigerant supply pump 24 (step 73, see FIG. 9).

When the inside of the system is under positive pressure or when the pressure becomes positive during the above-mentioned refrigerant introduction, the 31E solenoid valve 44 is closed (step 77), and the refrigerant supply pump 24 is driven in the reverse direction to drain the reservoir tank. 41 into the condenser 23 (step 79.80>. Even in the case of this forced introduction, the detected temperature is "set temperature - 3.0 °C (α6)").
(steps 74 and 75).
). In addition, if the liquid phase refrigerant in the water jacket 22 becomes insufficient during this refrigerant introduction, the second solenoid valve 57fcr
The flow path BJK is temporarily switched and the refrigerant supply pump 24't is driven in the forward direction to replenish the refrigerant (steps 78° and 81.8
2).

As a result of the water level rise control in the condenser described above, after the system temperature is guided to the upper limit temperature to the lower limit temperature in step 7, temperature control (steps 51 to 54) using only the cooling fan 34 described above is performed.

In this way, the liquid level control inside the capacitor 23 always keeps the system temperature at "set temperature +2.0°C" and "set temperature -40°C".
'' range (step 7), and even if the set temperature changes drastically due to a sudden change in operating conditions, for example, the heat dissipation capacity of the capacitor 26 can be changed quickly over a wide range. At the same time, the resulting change in the amount of condensation immediately suppresses boiling of the refrigerant on the water jacket 22 side.

Since it has an accelerating effect, it is possible to follow the set temperature extremely well. Then, the cooling 77 and 34 are controlled so as to bring the temperature inside the system further within the range of "set temperature range 0.5°C" (step 52). Control is achieved.

On the other hand, when the outside temperature is low, specifically when it is below 0°C, the above-mentioned condenser water level rise control is canceled when it continues for a maximum of 5 seconds (step 7'76.85).
Thereafter, after clearing the timer (2) (step 86), the process again proceeds to the warm-up control shown in FIG. In other words, when you drive downhill for a long time when the outside temperature is low, the system temperature may not recover to the target temperature even if the inside of the condenser 23 is completely filled with liquid phase refrigerant, so By canceling the refrigerant introduction, damage to the condenser 26 due to unnecessary driving of the refrigerant supply pump 24 and pressure rise is prevented. In the warm-up control (step 4), as described above, the system is kept in an open state and waits for the temperature to rise due to an increase in engine load or a decrease in running wind.

Next, FIG. 12 shows key OFF control (,X,
11).

This is first set to the set temperature t-80℃ (step 9
4), the above-mentioned water level reduction control in the condenser is performed to maximize the heat dissipation capacity of the condenser 26, and the cooling fan 34t is driven for about 10 seconds at the maximum for forced cooling (step 95, 96, step 56), and the temperature inside the system is sufficiently low (e.g. 80°C).
(Step 93), the system becomes negative pressure (Step 97), or a certain period of time (for example, 1 minute) has elapsed (Step 98).
(Step 99). When the power is turned off, the 111th solenoid valve 46, which is a normally closed solenoid valve, becomes "closed," and the third solenoid valve 44, which is a normally closed solenoid valve, becomes "open," resulting in a decrease in the temperature or pressure in the system. Along with this, liquid refrigerant is naturally introduced from the reservoir tank 41 through the first auxiliary refrigerant passage 66, and eventually the entire system is filled with liquid refrigerant in preparation for the next startup. become. In addition, when the liquid refrigerant is introduced, it flows into the system through the condenser 23't, so a small amount of air may enter the condenser tube for some reason during operation and adhere to the inside of the condenser tube. The thread can be reliably discharged upward even in the case of

On the other hand, the ignition key may be turned ON again during the key OFF control, but in this case, the process proceeds to Step 100 based on the determination in Step 92, and the cooling fan is turned on based on the information previously evacuated (Step 91). 34 and the set temperature is restored, and step 95.9
8 software timer ■, ■ all clear (step 10
1) Return to the control state that was in progress before the L key was turned off.

Effects of the Invention As is clear from the above explanation, according to the present invention, which variably controls the boiling point temperature of the refrigerant to control the liquid level in the condenser, the system can be maintained without being affected by disturbances such as wind when the vehicle is running. It becomes possible to quickly make the internal temperature follow the target temperature, and it is possible to realize temperature control at a high temperature of 1 degree. When the outside temperature is low, excessive refrigerant is not introduced into the condenser, so problems such as increased power consumption due to unnecessary operation of the refrigerant supply pump and damage to the condenser due to increased pressure in the system occur. There is no.

[Brief explanation of drawings]

Fig. 1 is a functional block diagram showing the purchase price of this invention, Fig. 2 is a configuration explanatory diagram showing an embodiment of this invention, Figs.
Fig. 5, Fig. 6, Fig. 7, Fig. 8, Fig. 9, Fig. 10
11 and 12 are flowcharts showing the details of control in this embodiment. 1...Water jacket, 2...7 Densa, 6
... Reservoir tank, 4... Refrigerant supply means, 5...
- Refrigerant introduction means, 6... Refrigerant discharge means, 7... Liquid level detection means, 8... Temperature detection means, 9... Water jacket side liquid level control means, 10... Target setting means, 1
DESCRIPTION OF SYMBOLS 1... Capacitor side liquid level control means, 12... Outside temperature detection means, 13... Liquid level rise release means, 21... Internal combustion engine, 22... Water jacket, 23... Capacitor, 24... Refrigerant supply pump, 66... Lower tank, 64... Cooling fan, 65... Refrigerant circulation passage, 36... First auxiliary refrigerant passage, 67... Second solenoid valve, 41... ...Reservoir tank, 46...Second auxiliary refrigerant passage, 44...Third solenoid valve, 45...Air discharge passage, 46...First solenoid valve, 51...Control device, 52
...First liquid level sensor, 54...Temperature sensor, 54...
・Second liquid level sensor, 55...Negative pressure switch, 56...
・Outside temperature sensor. Figure 3 Figure 4 Figure 5 Figure 7 Figure 8 Figure 9

Claims (1)

[Claims] (1) A water jacket in which liquid phase refrigerant is stored, and refrigerant vapor generated in this water jacket are introduced,
and a condenser from which condensed liquid refrigerant is taken out from the bottom, the water jacket kept in a sealed state, a reservoir tank provided outside of the condenser, and a water jacket from the condenser or the reservoir tank. a refrigerant supply means for supplying a liquid phase refrigerant into the water jacket; a liquid level detection means for detecting the liquid level position of the liquid phase refrigerant in the water jacket; water jacket side liquid level control means for controlling the supply means; refrigerant introduction means for introducing liquid refrigerant from the reservoir tank into the condenser; and refrigerant discharge means for discharging the liquid refrigerant from the condenser into the reservoir tank. and a temperature detection means for directly or indirectly detecting the temperature of the liquid phase refrigerant in the water jacket, a target setting means for setting a target temperature according to the engine operating conditions, and a temperature detecting means for directly or indirectly detecting the temperature of the liquid phase refrigerant in the water jacket, a target setting means for setting a target temperature according to engine operating conditions, and a a condenser-side liquid level control means for controlling the refrigerant introducing means and the refrigerant discharging means based on the above, an outside temperature detection means for detecting the outside temperature, and when the outside temperature is low,
A boiling cooling device for an internal combustion engine, comprising liquid level rise canceling means for canceling the operation of the refrigerant introducing means within a certain limit.