JPS6291617A - Evaporative cooling device of internal combustion engine - Google Patents

Abstract

PURPOSE:To continue the drive of an engine without hindrance, by lowering the level of coolant in a water jacket down to a predetermined level during cold-start of an engine in order to aim at promoting the engine warm-up, and by automatically shifting the control of the engine to the next step after a predetermined time elapses. CONSTITUTION:During an engine being stopped, liquid phase coolant is filled in a water jacket A. When the engine is started, if the temperature of the engine is below a set value, an operation initiating signal output means E starts the operation of a liquid phase coolant discharge means C in accordance with the result of detection by a temperature detecting means D. Then, liquid phase coolant moves from the water jacket A into a reservoir tank B, and when the level of coolant in the water jacket A lowers down to a predetermined level, an operation terminating signal output means H stops the operation of the above-mentioned discharge means C in accordance with a liquid level detecting means G. Further when a predetermined time elapses, the above- mentioned discharge means C completes its operation in accordance with an output from a timer means F.

Description

[Detailed Description of the Invention] Industrial Application Field This invention stores a liquid phase refrigerant up to a predetermined level in a water jacket, cools various parts of an internal combustion engine by boiling and vaporizing the refrigerant, and discharges the generated refrigerant vapor. The present invention relates to a boiling cooling system for an internal combustion engine which condenses the condensed water in a condenser and supplies the water to the water jacket again.

Prior Art The present applicant has developed a closed-loop refrigerant circulation system mainly consisting of a water jacket, a condenser, and a refrigerant supply pump.The refrigerant vapor generated in the water jacket is guided to the condenser and condensed, and then the liquid level Various boiling cooling devices have been proposed in which the refrigerant is supplied to the water jacket again by a refrigerant supply pump based on detection by a sensor (for example, Japanese Patent Laid-Open No. 60-36712, Japanese Patent Laid-Open No. 60-60)
-36715, etc.) In this boiling cooling system, unlike a flowing water type cooling system, the liquid phase refrigerant accumulates in the water jacket and receives the combustion heat, so the time required for warming up can be completely shortened. This is one of the advantages.

In order to achieve even more rapid warm-up, the present applicant has developed a boiling cooling system in which the refrigerant liquid level in the water jacket is kept at a low level while the engine is stopped, and a slow contact operation is performed in that state. The device was previously proposed (4!!F Application No. 1983-100158).

Problems to be Solved by the Invention However, if the refrigerant liquid level in the water jacket is lowered and air is introduced into the upper part while the engine is stopped as described above, the inner wall surface of the water jacket will be exposed to air for a long period of time. This may lead to oxidation and corrosion of various parts.

The object of the present invention @1 is to fill the inside of the automatic jacket with a liquid phase refrigerant while the engine is stopped, and to quickly lower the refrigerant liquid level when the engine is started to achieve rapid warm-up.

Furthermore, when lowering the refrigerant liquid level at the beginning, if the liquid level is stopped at a predetermined level based on the detection signal of the liquid level sensor installed in the water jacket, it will be possible to prevent the refrigerant level from dropping at a predetermined level. For example, when the refrigerant liquid level in the quarter jacket cannot be lowered to a predetermined level because the amount of refrigerant in the reservoir tank is too large, there is a possibility that the desired control will not be possible.

Objects # and 2 of this invention are to enable operation to continue without any trouble even if the refrigerant liquid level does not drop to a predetermined level for some reason during startup.

A means to solve problems! Figure 1 is a functional block diagram showing the configuration of the present invention, which includes a water jacket A that is filled with liquid refrigerant when the engine is stopped, and a reservoir tank that is located at a relatively low level and is open to the atmosphere. B, and a liquid phase refrigerant discharge means C that allows the liquid phase refrigerant to move from the water jacket A to the upper reservoir tank B and allows air to be introduced into the water jacket A4 section. The above-mentioned liquid phase refrigerant discharge means ch, such as a solenoid valve that opens and closes the upper part of quarter jacket A, water jacket A and reservoir tank B
It consists of a solenoid valve that opens and closes between the

In addition, if the temperature is below a predetermined temperature at the time of starting the engine, the temperature detecting means detects the temperature of the engine, and the liquid phase refrigerant discharging means CK detects the temperature of the engine.
Production start signal? an operation start signal/signal output means E for outputting an operation start signal/signal output means E; a timer means F for outputting a predetermined signal when the liquid-phase refrigerant discharging means C's fIr-power has been lightened for a predetermined time from the start; and a refrigerant liquid in the water jacket A. A predetermined signal when the surface drops to a predetermined level? When receiving any one of the signals from the output liquid level detection means G, the timer means F, or the liquid level column means G, the liquid phase cooling means CK outputs an operation end signal? It is equipped with a force means H for outputting encouragement/subsignals.

When the engine is stopped, water jacket A is filled with liquid refrigerant.

When the engine is started, if the engine temperature is in a cold state at a predetermined temperature or lower, the liquid phase refrigerant discharge means C starts operating. In other words, at the same time that the liquid phase coolant moves from water jacket A to reservoir tank B located at a lower position due to the water head difference, air is introduced into the upper part of quarter jacket A.
5 Water jacket) The refrigerant liquid level in A quickly decreases, and when this refrigerant liquid level falls to a predetermined level, the operation of the liquid phase refrigerant discharge means Cr) is terminated. Therefore, the amount of cold # that quarter jacket AK possesses is small, and the upper part? This means that warm-up operation will not be performed in a state insulated with air. In addition, if the refrigerant liquid level does not fall to the predetermined level promptly for some reason, the operation of the liquid phase refrigerant discharge means C is terminated when the predetermined time nfl has passed 1, and the subsequent control is carried out at the predetermined level. It continues in the same way as when it has dropped to the level n.

Embodiment FIG. 2 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 a condenser for condensing a gas phase refrigerant. , 4 and 1 respectively indicate dynamic refrigerant supply pumps.

The upper water jacket 2 is formed over both the cylinder block 5 and the cylinder head 60 so as to surround the entire outer periphery of the cylinder and combustion chamber of the internal combustion engine 1.
The upper part, which normally contains all gas phases, communicates with each other in each cylinder, and a steam ratio lower for counting is provided at an appropriate position in the upper part. With this steam ratio lower σ, the steam manifold 8 collects n to each other, and the steam passage 9
The upper inlet aaVc of the capacitor 3 is connected to the upper inlet aaVc of the capacitor 3, and the upper inlet is the heater core installed indoors, and the upper inlet is the heater inlet surface! ! ? G11?
It is connected to the cylinder block 5 side of the water jacket 2 through the connector, and the lower outlet is connected to the heater outlet passage 12? It is connected to the cylinder head 6 side through. A heater pump 13 for circulating the liquid phase refrigerant between the water jacket 2 and the heater core 10 is interposed in the upper lip biheater outlet passage 121C1. This is a refrigerant mixing passage that is connected to the steam manifold 8 and is connected to the steam manifold 8, and sends a small amount of liquid phase refrigerant to the condenser 3 in order to prevent uneven distribution of liquid in the refrigerant during winter, that is, when the heater is in use. It fulfills its function.

Upper If capacitor 3, upper e inlet 3a? It consists of an upper tank 15, a core part 16 mainly consisting of fine tubes along the vertical direction, and a lower tank 17 that temporarily stores refrigerant that is condensed or liquefied in the core part 16. It is installed in a position such as the front where it can receive wind from both directions.Furthermore, a WIt1 type cooling fan 18 for forced cooling is provided on the front or rear side of the n1. In addition, the BVC refrigerant circulation passage 19 is relatively lower than the above-mentioned lower hook 17.
One end of the is connected, and the first
One end of the auxiliary refrigerant passage 20 is connected. The other end of the refrigerant circulation passage 19 is connected to the refrigerant passage 2a provided above the 711 under block 6 of the water jacket 2, and the refrigerant supply pump 4 is interposed in the passage. , the discharge ratio 1u of this refrigerant supply pump 4
A second thunder magnet valve 21 consisting of a three-way W valve is installed in ll.
ing.

31 is a reservoir tank provided outside the refrigerant circulation system in which the upper F water jacket 2 and the condenser 3 are living bodies, and this reservoir tank is opened to the atmosphere through a cap 32 having a ventilation function. At the same time, the upper water jacket 2 is installed at a relatively low level, and the upper first auxiliary refrigerant passage 20 and the second auxiliary refrigerant passage 20 are located at the bottom of the upper water jacket 2.
@3 Auxiliary refrigerant passages 33 and 34 are in contact. During the passage of the first auxiliary refrigerant passage 20, the third electric valve 35 is normally open. - Be prepared. Also, upper P first auxiliary refrigerant passage 3
3. It is connected to the heater core 10 of the heater outlet passage 12 and the heater pump 13 via a fourth solenoid valve 36, which is a three-way air control valve for flow path switching. Further, the third auxiliary refrigerant passage 34 is connected to the refrigerant circulation passage 19 via the upper Ml'' second electromagnetic valve 21.
The second solenoid valve 21 communicates the discharge port of the refrigerant supply pump 4 with the reservoir tank 3 via the third auxiliary cooling passage 34'ff, and the water jacket 2VC through the refrigerant circulation passage 19. "Flow path B"
It has a structure that can be switched between. In addition, the above-mentioned 4th City Benchmark 3
6 is a flow path A that connects the suction boat of the heater pump 13 to the reservoir tank via the second auxiliary refrigerant path 33.
” and a “flow path B” that communicates with the heater core 10 via the heater outlet passage 12 .

10,000, an air passage 37 for introducing air into the system and discharging air from the system is connected to the upper wall of the steam manifold 8, which is the top g3 of the refrigerant circulation system mentioned above. and its tip is connected to the upper part 9 inside the reservoir tank 31.
There is a small opening in between. And in the upper 6e air passage 37,
The first always-closed type! ! A valve 38 is interposed.

Upper r each'@歿Valve 38, 2], 35, 36, heater pump 13, refrigerant supply pump 4, and cooling fan 1
8, it is controlled by a control device e41 using a so-called microcomputer system, and sensors are installed at the water jacket 2. A first liquid level sensor 42 disposed at the level and an appropriate position V of the water jacket 2
a second liquid level sensor 44 located relatively above the lower tank 17, a diaphragm negative pressure switch 45 located at the top of the circulation system, and a heater core. 10 refrigerant outlets, and nine heater temperature sensors 46.

Next, FIGS. 3 to 16 show the same contents of the control executed by the control device 41. This is a flowchart shown in FIG. In addition, in the figure, the refrigerant supply pump 4f "pump ■",
Heater pump 13? "Pump ■", 1st to IE4 solenoid valve blades, 21. Deaf, 36 "Solenoid valve■" ~ "1!r Solenoid valve■
” and the liquid level inside the water jacket 2?
First, to briefly explain the main points of control, Fig. 3 is a main flowchart showing the entire control. When more control begins,
If it is a cold start at a predetermined temperature (for example, 45°C) or lower, the process proceeds to rapid warm-up control (step 3), where the engine rIA
After quickly raising the temperature and discharging a sudden amount of air from the system, warm-up control (step 4)? After that, the refrigerant boils? The process from step 6 onwards corresponds to a steady operating state in which the boiling and condensing cycle of the refrigerant takes place in the system. The cooling fan 18 is controlled by the
In the (b) part, there is no variable control of the refrigerant liquid surface adhesion within the condenser 3, that is, the substantial heat dissipation area. Also, liquid level control (steps 6, 23, 34)
Through these processes, the refrigerant liquid level in the water jacket 2 is always maintained near the level set by the first liquid level sensor 42. Therefore, after the slow welding is completed, the loop of steps 6 to 41 is, in principle, repeated until the engine stops.
Warm-up control (step 4) is executed again only when the system temperature drops abnormally (step 39), such as during low load in winter.

On the other hand, when the system temperature is 45° C. or higher at the time of starting, VC means a warm-up restart, so unnecessary rapid warm-up control (step 3) is omitted.

Further, FIG. 4 and FIG. 5 show the interrupt processing executed every footstep. In the interrupt processing (1) of @4119, it is determined whether or not the engine is rotating (step 42), and during operation, the optimal control temperature for the engine operating conditions is sequentially determined. In addition to setting (step 45), predetermined processing is performed after the engine is stopped. In the interrupt processing (2) of FIG. 5, the heater pump 13 is turned on based on the heater switch (not shown).
operation? In addition to controlling the amount of heat dissipated from the heater core 10, it also stabilizes the amount of heat dissipated and reduces power consumption. In order to achieve this, the flow rate of the heater pump 13 is controlled based on the heater outlet liquid temperature (the temperature detected by the heater temperature sensor 46) (steps 55 and 5).
6'). Note that the heater pump 13 may be used for other purposes such as securing the liquid level in the water jacket 2, and the interruption of the 1% fIh interrupt process (2) is prohibited (step 58. 71.99.118 etc.).

Next, Figure 6 shows the details of the rapid warm-up control (step 3) that is executed immediately after startup as described above.In addition, at the time of this recommendation to start the machine, normally the lamp system is filled with liquid phase refrigerant (e.g. The VC is almost filled with ethylene glycol aqueous solution), and a small amount of liquid phase refrigerant remains in the reservoir tank 311C. Rapid warm-up control starts by opening the 38 first N solenoid valves.
, set the second solenoid valve 21 as "flow MBJ", set the third w regulating valve 35?r closed J, and set the fourth solenoid valve 36 as "flow path A" (step 59).
, the water jacket 2, the condenser 3, etc. are communicated with the reservoir tank 31 through the second auxiliary refrigerant passage 33.

Note that the heater pump 13 is an impeller pump or the like that allows refrigerant to flow through it when the heater is stopped. Therefore, the liquid phase refrigerant inside the water jacket 2, condenser 3, etc. is transferred to the reservoir tank 31 due to the water head difference, and air is gradually introduced from the top.In principle, this refrigerant is discharged by water. The refrigerant liquid level in the jacket 2 is detected by the first liquid level sensor 4.
2 (step 62).
), the fourth lightning valve 36 is switched to "flow path B", thereby ending the P'l: phase (step 65). In addition, if the temperature rise of Ij is extremely rapid than the operating condition r, the refrigerant temperature 9
Refrigerant discharge ends when the temperature reaches 0°C. Also, if the drop in the liquid level is delayed due to some reason, the predetermined time ts (for example, 30
60 seconds), the refrigerant discharge is similarly terminated (step ω, 61). The above time t5 is
Taking into account the passage resistance of the heater pump 13, etc., the setting is normally made to be sufficient to reduce the pressure to the above-mentioned setting level.

By moving the liquid phase refrigerant to the reservoir tank 31 as shown above, the amount of cold water that receives heat in the water jacket 2 is reduced, and slow welding operation is possible with the upper part being insulated by the sudden air. As a result, the temperature of the refrigerant within the water jacket 2 rises rapidly. When the refrigerant WIN reaches 91° C., the fourth solenoid valve 36 is set to “flow path A” and the heater pump 13 is activated (steps 72 and 73).

When the liquid phase refrigerant is forcibly introduced into the system from the reservoir tank 31 by this fIK, it is suddenly collected in the upper part of the system as a non-condensable gas and then discharged through the air passage 37. Further, if the system temperature drops to 89° C. or lower due to the introduction of the refrigerant, the introduction of the liquid phase refrigerant is interrupted until the temperature recovers to avoid a warm drop in excess I (steps 67 to 70).
The sudden air discharge operation has a predetermined value t6 (
(for example, about 10 to 30 seconds). The time is set to be sufficient to fill the inside of the cooling system with liquid phase refrigerant, and by this time, the air inside the system can be completely discharged.

In addition, when the heater switch (not shown) is turned ON, such as during winter, the liquid phase refrigerant in the water jacket 2 is circulated and supplied to the heater core 10 within a certain range to improve the heating performance.
It is ensured (step 67).

When the rapid warm-up control described above is completed, the process proceeds to the warm-up control shown in detail in FIG. 7. This warm-up control closes the rush passage 37f and closes the first auxiliary refrigerant passage 20? The process waits (steps g0 and 81) until the temperature of the refrigerant in the water jacket 2 further rises to near the target set temperature while keeping the system open (step 78). ℃'', the excess refrigerant is forcibly discharged to the reservoir tank 3 by the refrigerant supply pump 4 (step 85). This is because if boiling starts due to a sudden increase in heat load, there is a risk that the excess refrigerant will be discharged slowly through the first auxiliary refrigerant passage 20'', causing an undesirable rise in temperature. If there is negative pressure in the system, the third solenoid valve 35
ft is closed, and when positive pressure is applied, the 3'Tl magnetic valve 35 is opened to use natural discharge (steps 87 to 89). As a result of this refrigerant discharge, the refrigerant liquid level in the water jacket 2 or the condenser 3 When the refrigerant liquid level falls below the set level of the first and second liquid level sensors 42 and 44 (step 82), and when the internal temperature of the refrigerant system rises by more than "set temperature + 0.5 °C" (step 86) ) within the VC? At the end stage of the warm-up ft1l+ operation in which the warm-up control is completed by sealing, the liquid phase refrigerant in the water jacket 2 normally starts boiling under reduced pressure.

The optimum VC tread is set to the set temperature of the upper WE' within a range that does not exceed the boiling point of the refrigerant under normal pressure, for example within a range of 80 to 110 degrees Celsius, depending on the operating conditions such as engine load and rotation speed. j
As mentioned above, the interrupt processing (1) in Figure 4
(Stella 7"44, 4
5). In addition, the specific operating conditions include the suction negative pressure and rotational speed for gasoline engines, the pulse width and period of the injector drive pulse in the case of a heavy child control fuel injection method, and n for diesel engines. After the warm-up control in which the opening degree, rotation speed, etc. are determined, the control loop from step 6 to step 41 is repeated as described above.

First, when the amount of heat generated by the engine and the amount of heat dissipated from the condenser 3 are balanced at the boiling point of the refrigerant near the set temperature, specifically, when the refrigerant temperature is within the range of "set temperature ±0.5°C", Based on the judgments in steps 7 and 20, only the liquid level control (1) in step 6 is actually executed. FIGS. 8 and 9 show details of this liquid level control (1). That is, as a result of boiling starting in the water jacket 2, the refrigerant liquid level gradually decreases, but when the quarter jacket side liquid level falls below the level set by the first liquid level sensor C, the refrigerant supply pump 4, the liquid phase refrigerant is replenished from the condenser 3 side to the water jacket 2 (steps 90 and 91). Therefore, the cycle of boiling and condensation of the refrigerant is repeated in the closed refrigerant circulation system, and the water The refrigerant liquid level in the 1 jacket 2 is always maintained stably near the set level of the 1 liquid level sensor 42 fsIIc. Here, the above refrigerant supply t? If the refrigerant liquid level does not recover to the set level after counting for more than 10 seconds (
In step 98), it is possible that there is no liquid-phase refrigerant in the lower tank 17, so if there is a negative pressure in the system, the third electric valve vane pipe is opened to introduce refrigerant from the reservoir tank 31, and If the pressure is positive, then the heater pump 13? Use I! from reservoir tank 31 to water jacket 2! Replenish the refrigerant pipes (steps 100, 101, 10)
2) If more than one second has elapsed, the heater pump 13 is used to supply the refrigerant regardless of the positive or negative pressure in the system. Despite this, the image created by the heater pump 13,
If the refrigerant is refilled, there is a risk that the amount of refrigerant in the system will be excessive and the temperature will rise.
35? The heater pump 13 is opened to allow the refrigerant to be naturally discharged due to the internal pressure (steps 103 to 105).Also, as described above, the heater pump 13 is turned on the flow rate side of the heater production eW# by the interrupt process (2). .

When replenishing the water jacket 2, the maximum flow rate is always given (step 99).

Next, when the above-mentioned temperature equilibrium state is reached and the system temperature rises to ``set temperature + 0.5℃'' or higher due to disturbances such as a decrease in direct running air or changes in the set temperature itself due to changes in operating conditions, cooling is performed. The fan 18 operates to promote condensation using forced cooling air (steps 7 and 10). When the liquid phase refrigerant is above the set level of the sensor shrine, the condenser 3 itself has sufficient heat dissipation capacity, and the forced cooling air has little effect on the liquid phase refrigerant area of the condenser 3. ,
The fan voltage is set to rLOWJ and rotated at low speed (step 11), and only when the fan voltage is below the set level of the second liquid level sensor 44? r HtghJ and high speed rotation (step 9). In addition, when the former low speed rotation state g continues for 10 seconds or more, the cooling fan 1B is stopped, and the cooling fan 18 is quickly shifted to the condenser water level low regime a (step) to be described later. Drive only to the minimum necessary.

Also, by forced cooling of the cooling fan 18, "set temperature - 0"
When the temperature drops to 5℃, the cooling fan 1811I
The process stops (step 14).

■ i　　　jcnj　5“1・811”101°゛.

1 As long as the temperature is within CJ (step 20), temperature control is performed only by the cooling fan 18. Promote and suppress condensation by this cooling fan 18, and immediately change the boiling temperature in the system 11h? Therefore, very responsive and fine warm control can be realized. During this time, the liquid level in the automatic jacket 2 is reliably kept approximately constant by the liquid level control (1) in step 6 mentioned above. Setting temperature +3.Q
℃” or more? Temperature -3,0q or less 1''
When , the condition i shown in the center part of Figure 3 is
There is no variable control of the substantial heat dissipation area of the sensor 3;
b.

First, when the temperature exceeds the set temperature +3.0℃,
h, 12th ryIff Proceed to the water level lowering control in the condenser 11 in step 27, which is detailed, and the refrigerant supply pump 4 1: Forcibly discharges the liquid phase refrigerant from the condenser 3 to the reservoir tank 31 (step 127)
When the pressure inside the system is positive, the third solenoid valve 35 is opened to use the natural discharge utilizing the pressure difference inside and outside the system (steps 123 to 125).
. This refrigerant discharge means that the system temperature is "set temperature + 2.5℃"
It decreases to below and ends at 9 stages (steps 30 to 33'
) l.

In this way, ending the process at a slightly higher temperature than the set temperature is
This is because there is a delay in the response of temperature changes to a drop in the liquid level.Furthermore, if the speed of refrigerant discharge is excessively high, the response delay may cause hunting in the system temperature. Air timer ■ (Step 25)
? to operate the refrigerant discharge intermittently (step 2
5-29) In addition to suppressing the discharge speed, if the set temperature itself changes from a high temperature range to a low temperature range due to changes in operating conditions, some 71
Since it is preferable to improve the followability of the temperature and to set the temperature at 90,000 yen even if we ignore the
6, 47, 24) l.

Furthermore, when shifting to the water level reduction control described above in the condenser, the cooling fan 18 is often already stopped due to the determination in step 12, but the cooling fan 18? It is operated again at low speed to ensure a rapid conductivity drop (step 8.11). Then, the liquid phase refrigerant in the lower tank 17 reaches the second liquid level sensor 4.
4's crotch? When the water level drops below this level, the condenser zone water level lowering control is terminated regardless of the temperature, and from then on, the rotational speed of the cooling fan [8] is set to high speed rotation to promote condensation (steps 22, 8, 9, 10).

In order to maintain the liquid level on the war jacket 2 side while the refrigerant is being discharged from the condenser 3, the steps shown in Figs.
It is processed by liquid level control (2) as shown in the figure. This 1
is basically the same recommendation as the control shown in FIGS. 8 and 9 above.
'll: is to be performed, but after 10 seconds? When replenishing the refrigerant with the heater instep pump 13, the refrigerant supply pump 4σ condenser 3 is drained to make sure the water level in the condenser 3 is lowered (steps 121 and 108).

However, after 2 () seconds have elapsed, priority is given to securing the liquid level in the water jacket 2 (steps 122, 108).

On the other hand, due to low-load tanks, etc., the system temperature may drop to "set temperature - 3".
, 0°C" or less, proceed to step 37 to control the increase in the water level in the condenser as shown in FIG. The heat dissipation surface 8t is effectively reduced. When this refrigerant is introduced, the system temperature is 2.5°C below the operating temperature.
” or more, the process ends (step 39). This end temperature is also set in consideration of the responsiveness of the temperature drop, and as in the case of refrigerant discharge, the refrigerant introduction speed is appropriately suppressed by the intermittent operation w1 of the third solenoid valve, Temperature hunting is attempted to be reduced (steps 35 to 38).

Also, during this refrigerant introduction, Fig. 13 I! The liquid level control (3) shown in Fig. 14 maintains the refrigerant liquid level of 2 yen in the water jacket. In this case as well, after 10 seconds have elapsed, the heater pump 13 is used to ensure the liquid level with priority. Note that cavitation is likely to occur because the refrigerant supply pump 4 sucks the refrigerant in the lower tank 17 that is close to the saturation temperature, but the heater pump 13 sucks low-temperature liquid phase refrigerant from the +1 reservoir tank 31, so cavitation will not occur. It is possible to always provide reliable cold supply.

As described above, along with the control of the cooling fan 18, the effective heat dissipation area of the condenser 3 is controlled to vary by 5'f to maintain the system temperature near the set temperature. When driving downhill in winter [5], there is a possibility that the temperature will not recover as expected even if the effective heat dissipation area of the capacitor 3 is narrowed. Therefore, if the temperature inside the system drops below 76°C, for example, the warm-up control (step 4) is performed again (step 39), as described above, and vice versa. If the temperature inside the Tan f vC system rises to overcurrent,
For example, when the temperature is 110°C or higher and the pressure is positive, the water drop avoidance control in step 41 shown in Fig. 16 is executed.
;) h This high-performance/avoidance control is basically the 3rd w valve control 35
'f-'open' (step 144) and set the system pressure? -1
At the same time as the steam is released, air is pushed out from inside the condenser 3 along with the steam. Most of the causes of abnormally high temperatures are due to the fact that vC nitrogen accumulates in the fine tube of the condenser 3 and prevents condensation when air exhaust is insufficient. Valve 35? By opening and forcing out air, an effective temperature reduction is achieved. In addition, in the event that the temperature inside the system increases further to 115°C or higher due to a failure, etc., the first municipal valve 38 will also open at the same time to release the pressure inside the system through the air passage 37, and the cooling fan 18fI will also open. - Operate at high speed and force cooling (step 146). The first municipal valve 38 of the upper P closes when the humidity in the system becomes 112° C. or less, and further closes when the third solenoid valve 35ij becomes 106° C. or less or the pressure in the system becomes negative.

Also, even during the above-mentioned system opening, the refrigerant is not replenished into the water jacket 2 by the processing after step 150, and the refrigerant liquid level is maintained near the set level. Pump 13 is in use (
Step 158). Furthermore, in order to prevent the refrigerant liquid level in the condenser 3 from rising due to the condensed refrigerant, the refrigerant is discharged by the refrigerant supply pump 4 when necessary (
Step l64. ~166).

Next, when the engine is stopped by turning the ignition key OFF, etc., in the interrupt processing (1) shown in Fig. 4, the installed IP temperature? Set it to ℃ (
Step 49). From this flK, the above-mentioned water level reduction control in the capacitor is performed 1, the heat dissipation capacity of the capacitor 3 is utilized to the maximum, and the cooling fan 18 starts to operate, so that the temperature is immediately lowered. Then, the temperature inside the system will drop to 85C, or the system will be at 9 pressure and 97℃.
or if the button seconds have elapsed, the power is turned off (steps 48 to 52). When the power is turned off, the third refrigerant valve, which is a lightning control valve that is normally open, opens, so liquid phase refrigerant is naturally introduced from the reservoir tank 31 due to the warm drop in the system, that is, the pressure drop. By then, the entire system is filled with liquid phase refrigerant in preparation for the next startup. This prevents damage to seals and the like due to negative pressure in the system and prevents air from entering while the engine is stopped.

Although one embodiment of the present invention has been described above in detail, the present invention is not limited to the above embodiment, and various modifications can be made. For example, in the embodiment described above, the liquid level during rapid warm-up is set to be the same as the liquid level that is the control target after the start of boiling, but they can be set to different levels.

Effects of the Invention As is clear from the above explanation, in the evaporative cooling system for an internal combustion engine according to the present invention, when the engine is cold started, the refrigerant liquid level in the quarter jacket is lowered to a predetermined level to perform rapid warm-up. Also, since no air is introduced into the quarter jacket etc. when the engine is stopped, problems such as oxidation and corrosion can be avoided. It never occurs. Even if the refrigerant liquid level cannot be lowered to a predetermined level for some reason, the process proceeds to the next control after a predetermined period of time has elapsed, so it can be operated without any problems. Can be continued.

[Brief explanation of drawings]

FIG. 1 is a functional block diagram showing the configuration of this invention, IE2
■An example of Keko's invention? Configuration explanatory diagram shown, W, 3 diagrams,
Figure 4, Figure 5, Figure 6, Figure 7, Figure 8, Figure 9, 1
1g10, 11, 12 and 13. No. 14111. What are the contents of control in this embodiment in Figs. 15 and 16? This is a flowchart showing 01...
・Internal combustion engine, 2...Quarter jacket, 3...Condenser, 4...Refrigerant supply pump, 1 (1...Heater core, 13...Heater instep pump, 17...Lower tank, 18... - Cooling fan, 19... Refrigerant circulation passage, 20... Third auxiliary refrigerant passage, 21... Second' [
4 valves, 31...Reservoir tank, vane...2nd auxiliary refrigerant passage, 34...3rd auxiliary refrigerant passage,...31st
#Solenoid valve, 36...4th solenoid valve, "...air passage, (
...First city magnetic valve, 41...Control device, C...First
Liquid level sensor, 43...41 sensor, 44...2nd liquid level sensor 0;...: ■Learning D Figure 7j Figure 10

Claims (1)

[Claims] (1) When the engine is stopped, the water jacket is filled with liquid refrigerant, the reservoir tank is located at a relatively low level and is open to the atmosphere, and the liquid refrigerant is transferred from the water jacket to the reservoir tank. and a liquid phase refrigerant discharge means that allows air to be introduced into the upper part of the water jacket; a temperature detection means that detects the temperature of the engine; and a temperature detection means that sends an operation start signal to the liquid phase refrigerant discharge means if the temperature is below a predetermined temperature when starting the engine. a timer means for outputting a predetermined signal when a predetermined time has elapsed from the start of operation of the liquid phase refrigerant discharge means; and a timer means for outputting a predetermined signal when the refrigerant liquid level in the water jacket has decreased to a predetermined level Boiling cooling of an internal combustion engine, comprising a liquid level detecting means for outputting an output, and a means for outputting an operation end signal to the liquid phase refrigerant discharging means when receiving a signal from either the timer means or the liquid level detecting means. Device.