JPS614815A - Boiling/cooling device for engine - Google Patents

Abstract

PURPOSE:To ensure excellent radiating action of a capacitor, by a method wherein, in a device which effects cooling of an engine by means of the evaporated latent heat of a cooling solution, a lower tank, storing a liquefied coolant therein, is formed to the lower part of a capacitor, and a steam passage is connected to the tank. CONSTITUTION:In a titled device, a capacitor 26 is located so that a core part 27 is somewhat inclined, and a number of tubes 28, through which coolant steam is guided to the core part 27, are formed in a manner that a passage 31 (forming a liquid collecting part) on the back side 30 of the core is somewhat increased in a cross section. A lower tank 32, in which a liquefied coolant, radiated and condensed by each tube 28, is temporarily stored, is formed to the lower part of a capacitor 26, and a storing part 33 is connected to a water jacket 2 of an engine body 1 through a coolant passage 12 provided with a 3-way electromagnetic valve 34 and a feed pump 13. Further, a steam passage 35 is connected to the upper part of the water jacket 2, and the passage 35 is formed in a manner that it falls halfway therealong, and the other end is connected to the lower tank 32.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) This invention relates to engine cooling using the latent heat of vaporization of cold liquid.

(Prior art) Nli tilt the coolant in the 71-kuji V-ket.
! The present applicant has proposed an 8111P cooling system in which the latent heat of vaporization is used to efficiently cool the engine (Japanese Patent Application No. 145467/1983), which will be explained with reference to S11 in Fig. 7. Then, 1 is attached to the engine body, 2 +L cylinder block 3a3 and the cylinder head 4 are attached to the l-taja, and 5 is attached to the upper part of the water jacket 2, leaving a predetermined space at f51:Tl. It is a cooling liquid (refrigerant).

This coolant! 5 absorbs the heat of the engine and reaches a predetermined temperature (a), and tJc begins to rise, and evaporates while taking away the latent heat of vaporization. The steam is led to a heat exchange condenser 7 through a steam passage 6 connected to the upper part of the shoes 1 and 2.

Is there cold in condenser 7? A cooling fan (electric fan) 8 that sends Jl air is attached, and the evaporative cooling liquid is cooled by radiating heat to the outside ΔIS according to the air volume, and after being condensed to the original liquid, it is stored in the lower tank 9.

A liquid level sensor 10 is installed in the jacket 2,
When the liquid level drops as the coolant 5 evaporates, the control circuit 11 causes the return passage of the water jacket 2 (
A supply pump 13 installed in the refrigerant passage (12) is driven. The pump 13 circulates the coolant 5 in the lower tank 9 to the water jacket 2 via the electromagnetic valve 25 to form a closed circuit cooling system.

The control circuit 11 also drives the cooling fan 8 based on signals from various sensors (not shown) that detect engine rotation, accelerator opening, fuel supply, etc., such as a temperature sensor 14 that detects the coolant temperature. control and set the engine cooling temperature to the optimum value according to operating conditions. In other words, since the inside of the cooling system is a closed circuit, the boiling point of the cooling liquid can be lowered or lowered by changing the pressure inside the system.

For example, when the engine is under low load, with relatively little heat generation, the air volume of the cooling fan 8 is reduced to suppress the heat dissipation and condensation in the condenser 7 to some extent, and the pressure within the cooling system is increased to above atmospheric pressure. Reduce the boiling point of liquid 5 by nl. This maintains the engine coolant temperature at a high level (for example, 120° C.) to reduce cooling loss.

On the other hand, during high loads when the engine generates a lot of heat,
Cooling - Increase the air volume of NONO 8 to promote heat dissipation and condensation in condenser 7, and the pressure in the system will drop below atmospheric pressure, lowering the boiling point of liquid 5 and lowering the engine coolant temperature. (for example, 90°C) to ensure good cooling conditions.

Coolant 5? Jl: E The latent heat of vaporization is extremely large, and the heat dissipation effect of the evaporative coolant in the condenser 7 is sufficiently high.Even in cold weather, the engine can be efficiently cooled with a small amount of coolant 5, and its cooling temperature can be reduced. can be controlled responsively according to the operating condition A'1, and therefore an excellent cooling function can be obtained.

On the other hand, in this J-type system, when the engine is stopped and the coolant concentration +Et drops to near room temperature, the coolant that had evaporated until then liquefies and the pressure in the system drops considerably, causing a strong negative impact. may cause pressure.

Therefore, the auxiliary passage 15.16J5 and the solenoid valve 17.1
It is stored in the auxiliary tank 19 using the pressure difference between the pressure connected to the jacket 1 and 2 through 8! , : The supplementary coolant is introduced to the detection level of the liquid level sensor 20.

In addition, if air enters the water jacket 2 from the outside due to a drop in the system pressure, it can be eliminated.
An air passage 21 and a solenoid valve 22 are provided in the upper part of the steam passage 6. For example, at the beginning of engine startup, the air passage 21 and the auxiliary passage 16 are monitored and the supply pump 13 is driven to forcibly drain the cooling liquid from the auxiliary tank 19. , and adjust the coolant level to the specified level while blowing out excess air. This air is led to the upper air layer of the auxiliary tank 19 and discharged to the outside via the filter 23.

In this state, when the engine starts, the cold
When the temperature of the I liquid rises and reaches a predetermined temperature, the coolant starts to boil and focus, but the liquid level sensor 10.2/
The auxiliary passage 15 is opened in accordance with the detection level of l, the cold u1 liquid is boiled and evaporated under atmospheric pressure, and the evaporation pressure pushes the supplemented amount of cooling liquid back into the auxiliary tank 19 J'.

In this case, the supply pump 13 is driven according to the liquid level sensor 1o, and the cooling liquid is sent from the lower tank 9 to maintain the liquid level in the jacket 2 at an appropriate level, so that the liquid level in the lower tank 9 reaches a predetermined level. It will be stopped.

As a result, while maintaining the evaporation pressure at atmospheric pressure, the system is returned to and set to the appropriate cooling temperature of 118 & 6 m. Therefore, it is possible to prevent air from entering the system.
Therefore, the heat exchange efficiency in the condenser 7 is maintained well.

In this way, IJ"C can always obtain the accurate cooling effect of boiling cooling, maintain high cooling performance, and adjust the boiling point pressure of the coolant according to the J! It is possible to arbitrarily lower the cooling temperature to below atmospheric/E, and as mentioned above, it is possible to set the cooling temperature to below 100°C (when using water) when the engine is under high load. .

In addition, in the above device, since the engine can be cooled with a small amount of coolant, not only the water jacket 2 but also the condenser 7, the supply pump 13, etc. can be made small, and the cooling system can be made smaller and lighter.

In addition, since it is possible to shorten the warm-up time of the engine and the heat dissipation efficiency in the condenser 7 is good,
This has the advantage that the driving power of the cooling fan 8 can be reduced, and noise and fuel efficiency can be improved.

(Problems to be solved by the invention) However, in such a cooling device, there are two problems.
Since the structure was such that the steam boiled in the jacket 2 directly flows into the condenser 7 via the steam passage 6, the coolant that has not yet evaporated flows out of the jacket 2 along with the steam and flows into the condenser 7. Sometimes.

For example, when the engine is operating under high load,
Since boiling occurs actively, the cold 11 liquid is likely to flow out together with the boiling steam and flow into the condenser.
It will happen.

Since the condenser i F dissipates heat through steam, it has extremely good heat transfer C^ and heat dissipation efficiency.However, when a liquid coolant enters the condenser, the heat transfer rate deteriorates due to the liquid, and the heat dissipation efficiency of the vapor decreases. This caused the problem that the heat dissipation efficiency deteriorated considerably.

The purpose of this invention is to solve the above-mentioned problems by (1), (1) the coolant before evaporation does not flow into the condenser, (J, -).

(Means for Solving the Problems) The present invention connects an engine water jacket that is mostly filled with liquid phase refrigerant and a condenser whose interior is kept in a gas phase to a vapor passage through which refrigerant vapor flows in the upper part and a condenser. A closed circuit is formed in which the refrigerant circulates by communicating with the refrigerant passage that returns the liquefied refrigerant from the pump through the supply pump, and a cooling fan is installed to supply forced cooling air to the knee 1 Densor, and the liquid phase refrigerant is stored. In an engine boiling cooling system in which an auxiliary tank is connected to the closed circuit through a valve means, a lower tank for temporarily storing liquefied refrigerant is formed below the condenser, and the lower tank is provided with the liquefied refrigerant above the refrigerant storage level. Connect the steam passage.

(Function) Therefore, the refrigerant vapor from the water jackets 1 to 1 is once led to the lower tank via the vapor passage, rises from there and flows into the condenser, and along with this vapor, the refrigerant before evaporation flows into the water jacket. Even if it leaks into the steam passage, it does not enter the steam room, but flows directly into the lower tank.

(Embodiment) FIG. 1 is a cross-sectional view showing an embodiment of the present invention, in which 1 is an engine body, 2 is a water jacket 1 to . 26 indicates a capacitor.

As shown in FIGS. 2 and 3, the condenser 26 has a large number of tubes 28 arranged in a core portion 27 for guiding refrigerant vapor.
A heat dissipation fan 7/29 is installed between each tube 28.

The condenser +J 26 is installed so that the core surface is inclined to some extent, and each tube 28 is formed so that the cross section of the passage 31 (which becomes the liquid collection part) on the back side of the core is somewhat larger, as shown in Fig. 4. Ru.

In this case, each tube 28I may be formed to have a cross-sectional shape in which the width of the liquid collection portion 30 is large as shown in FIG. 5, or the overall width may be somewhat increased as shown in FIG.

On the other hand, in the lower part of the refrigerant 26, a lower tank 3 temporarily stores the liquefied refrigerant that has been radiated and condensed through each tube 28.
2 is formed, and the storage portion 33 with a large volume is the lower tank 3.
provided at one end of 2.

This reservoir 33 has a solenoid valve (three-way solenoid valve) 34,
A-
Connected to Tajireket 2.

A steam passage 35 is connected to the upper part of the tank jacket 2, but this steam passage 35 is formed so as to fall down in the middle, and the other end is connected to the side surface of the lower tank 32.

In this case, the steam passage 35 is connected to a central portion of the lower tank 32 above the storage portion 33 of the lower tank 32, that is, above the refrigerant liquid level stored in the lower tank 32.

A connecting portion 36 between the steam passage 35 and the lower tank 32 is formed in the shape of a flat duct so that the cross section of the passage extends to a certain extent within the lower tank 32.

Further, a chamber 37 is formed in the upper part of the condenser 26 and communicates with each tube 28, and this chamber 37 is connected to a steam passage 37 near the water seat wood 2 via a communication passage 38 of an air vent river.
connected to.

Note that the configuration and function of the part are the same as those in FIG. 7, so the same reference numerals are given and detailed explanation will be omitted.

With this configuration, the vapor of the refrigerant 5 boiled in the water jacket 2 is guided to the lower tank 32 via the vapor passage 35, but since this vapor is light, it rises when it enters the lower tank 32 and flows into the tube of the condenser 26. 28, where the heat is radiated and condensed.

Since the condenser 26 is tilted and HQ fiFl is applied, the liquefied refrigerant drips into the lower tank 32 through the liquid collecting section 31 in the tube 28 (-).

On the other hand, due to the boiling of the refrigerant in the tank 2 and the flow of its vapor, the refrigerant that has not yet evaporated may flow into the steam passage 35. It does not flow into the lower tank 32 from the passage 35 and enter the condenser 26.

In particular, when the engine is operated under high load, boiling becomes active and the liquid refrigerant tends to flow out, but even at such times, it is reliably prevented from flowing into the condenser 26.

In this way, the heat dissipation effect in the condenser 26 can be improved, and furthermore, the liquid refrigerant condensed in the condenser 26 passes through one place in the tube 2B and drips. Therefore, even higher heat dissipation efficiency of the capacitor 26 is ensured. As a result, boiling cold +
As a II device, it can always exhibit stable and excellent cooling performance.

Note that while the engine is stopped, refrigerant is introduced into the system from the auxiliary tank 19, but since a communication passage 38 for air venting is formed above the condenser 26, air may enter the condenser 26. However, the steam can be reliably discharged through the steam passage 35 and the air passage 21.

(Effects of the Invention) Even if liquid refrigerant flows out from the water jacket along with boiling steam, it does not enter the condenser, and good heat dissipation in the condenser can be maintained to maintain high cooling performance.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the present invention? jConstruction sectional view, Figure 2,
Figure 3 is an elevational view and side sectional view of the capacitor section, and Figure 4 is
The figure is a sectional view of the densifying tube taken along the line X-X in FIG. 3, FIGS. It is a configuration sectional view. 2... Two A-ta jackets, 8... Cooling fans, 1
DESCRIPTION OF SYMBOLS 1... Control circuit, 12... Refrigerant path, 13... Supply pump, 17... Solenoid valve, 19... Auxiliary tank,
26... Capacitor, 32... L] Watank, 34
...Solenoid valve, 35...Steam passage, 1 Patent applicant 1" San Jidosha Co., Ltd. Representative Patent attorney Masaki Goto! .

Claims (1)

[Claims] The engine water jacket, which is mostly filled with liquid-phase refrigerant, and the condenser, which maintains the interior in a gas phase, are connected by a vapor passage in the upper part through which the refrigerant vapor flows, and a refrigerant passage, in which the liquefied refrigerant from the condenser is returned via a supply pump. A closed circuit in which refrigerant circulates is formed, and a cooling fan is provided to supply forced cooling air to the condenser, and an auxiliary tank storing liquid phase refrigerant is connected to the closed circuit via a valve means. A boiling cooling device for an engine, characterized in that a lower tank for temporarily storing liquefied refrigerant is formed below the condenser, and the vapor passage is connected to the lower tank above the level of the stored refrigerant.