JPS60132026A - Inter-cooler device for engine with supercharger - Google Patents

Abstract

PURPOSE:To eliminate the need for using a pump for circulating a refrigerant and reduce power for driving a cooling fan by connecting a cooler body to a refrigerant condenser through an upper vapor pipe for allowing a refrigerant vapor to flow and a lower return pipe for allowing a condensed refrigerant to return and forming them into a closed circuit. CONSTITUTION:Immediately after the starting of an engine, a vacuum pump 27 is driven in accordance with the signal of a vacuum sensor 30, setting the pressure in a cooling circuit at a certain pressure (approximately 72mm.Hg). When a hot intake air heated by a supercharger passes through the air passage 16 of a cooler body 15, a refrigerant in the cooler body is heated. When the temperature reaches about 45 deg.C, the refrigerant begins boiling, flows from the vapor reservoir 18 of the cooler body 15 to a condenser 22 through a vapor pipe 20, is cooled by blast from a cooling fan, and condensed into the former liquid body. The refrigerant, which is condensed and liquefied, falls in the collecting chamber 26 of the condenser 22, and is returned to the cooler body 15 through the return pipe 21.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to an intercooler device that cools pressurized intake air of a supercharged engine using latent heat of vaporization of a liquid.

(Prior art) In order to increase the output of internal combustion engines, there are turbo superchargers, etc., which use exhaust gas energy to drive a returbin, and a compressor that is linked to this drives all of the air sucked into the engine. Are known.

This kind of supercharger forces a large amount of air into the cylinder compared to a naturally aspirated engine, so it is possible to increase the amount of fuel by that amount, making it possible to increase the total output without making the engine larger. .

However, when the intake air is compressed by this supercharger, the intake air temperature rises, and if this engine is used to supply the intake air as it is, the actual intake air filling efficiency will not increase much due to the decrease in air density. In gasoline engines, a problem arises in that knocking is more likely to occur as the intake air temperature increases, so the compression ratio has been lowered and the ignition timing has been delayed.

So, is this a problem? In order to eliminate the problem and maintain the excellent functions of a supercharger, is the intake air temperature raised? Intercoolers have been put into practical use that cool the air before it is sucked into the cylinder.

Figure 1 shows an air-cooled intercooler water supply (Automotive Engineering-Vol. 32.N [L9, P86-88 1978
[Refer to issue published in September 2017], the intake air pressurized by the supercharger 1 passes through the entire long intake passage 2, is installed at the front end of the vehicle 3, or flows into the main body 4, from where it passes through the entire intake passage 2 again. A throttle chamber 5 connected to an intake manifold (not shown)
sent to.

This cooler body 4 has the same structure as an engine radiator (not shown), and is designed to be cooled by the air flowing in from the front of the vehicle 3 when the vehicle 3 is running.For example, an intercooler Compared to the case without this, the intake air temperature is lowered as shown in FIG.

However, with an air-cooled intercooler like this.

Regarding the installation location of the cooler body 4, the intake passage 2 is
9. It's long. The volume of the passage must also be considerably large, which poses a problem in that a delay in supercharging response is likely to occur when the engine is accelerated. Furthermore, the air-cooled intercooler has a low heat exchange rate, and therefore, in order to lower the intake air temperature as shown in FIG. 2, there is a problem that a large cooler body 4 of η) must be used.

On the other hand, the intercooler shown in FIG.
The air supercharged to the engine 10 exchanges heat with the cooling water in the cooler body and is cooled.

This cooler body 6 also has almost the same structure as the radiator of the engine, and the cooling water is sent to the electric pump 12 and then to the radiator 13.
At the same time, air is blown to this heat radiator 13 from a cooling fan or the like, and the cooling water after heat radiation is circulated to the cooler body 6. 1.For water-cooled intercoolers like this.

The intake passage 9 is not so long.

In addition, since heat exchange is performed between water and air, relatively good cooling efficiency can be obtained, and as a result, compared to the air-cooled type mentioned above, a more stable supercharging response is ensured, and the cooler body 6 etc. can be made relatively smaller. It has the advantage of being

However, in such a water-cooled intercooler, it is necessary to circulate a large amount of cooling water (127), which increases the driving power of the bonder 12 and increases the burden on the battery, etc. There was an unavoidable problem. In addition, the intake air temperature can only be lowered to about the temperature shown in Figure 2, and if you try to lower it further, the cooler body 6
It was not possible to reduce the size of the radiator 13, and the cooling performance as expected was still not achieved.

(Object of the Invention) An object of the present invention is to solve such conventional problems and provide an intercooler device that is small and has excellent cooling performance.

(Structure and operation of the invention) The present invention provides an intercooler device for a supercharged engine, in which a cooler body ( evaporator) is installed.

And this cooler body and refrigerant condenser.

A vapor pipe through which refrigerant vapor flows in the upper part and a return pipe which returns condensed refrigerant in the lower part communicate with each other to form a closed-loop cooling circuit, and a means is provided for completely reducing the pressure within this cooling circuit.

The refrigerant filled in the cooler body absorbs heat from the pressurized intake air when it enters the cooler body, boiling and evaporating, and the vapor flows through the steam pipe to the condenser. and inflow.

In the condenser, the incoming steam is cooled and condensed according to the air flow rate from a cooling fan, etc., and the refrigerant, which has become a liquid, returns to the pump or condenser due to the height difference between the pump and the condenser. It is returned to the cooler body.

The latent heat of boiling and vaporization of such refrigerants is extremely large.

Moreover, the boiling point of the refrigerant can be lowered arbitrarily by reducing the pressure in the cooling circuit, and the refrigerant boils at a predetermined low temperature.
Therefore, all of the heat can be sufficiently removed from the pressurized intake force A.

On the other hand, the heat dissipation effect in the condenser that flows into the steam is significantly increased, making it difficult to pressurize intake air with a low-temperature refrigerant. It becomes possible to efficiently and accurately cool to a predetermined temperature.

In addition, the entire device can be made smaller, and even when a pump is used, the power required is extremely small, ensuring excellent performance as an intercooler.

(Embodiment) Fig. 4 is a cross-sectional view of the structure of an intercooler device according to an embodiment of the present invention, showing an intake passageway that guides intake air pressurized by a supercharger (not shown) to a throttle chamber (not shown) of an engine. A substantially box-shaped cooler body 15 is interposed in the middle of the cooler body 14 .

As shown in FIG. 5, this cooler main body 15 has a large number of rectangular pipe-shaped air passages 16 arranged at intervals inside it.
This air passage 16 is the intake passage 14 before and after the cooler main body 15.
connected to.

A large number of heat transfer fins 17 are protruded from the inner wall of the air passage 16, and the inside of the cooler body 15 except for the air passage 16 is formed to be separated from the intake passage 14 and the outside of the cooler body 15.

The cooler main body 1 above and below this air passage 16
5, a vapor reservoir section 18 and a liquid reservoir section 19 are formed with a space of a certain amount.

This refrigerant may be a normal engine coolant that is a mixture of water, antifreeze, and water, and in this case, 1 tll of air is filled in the passage 16 to the extent that it does not leak out at the time of maximum evaporation.

On the other hand, a steam pipe 20 with a relatively larger diameter than above the cooler main body 15 is connected to the vapor reservoir 18, and a small-diameter return pipe 21 on the side of the cooler main body 15 is connected to the liquid reservoir 19. Return to the steam pipe 20 on the opposite side of the main body 15! l
A refrigerant condenser 22 is disposed between the l pipe 21 and the refrigerant condenser 22 .

This condenser 622 has a structure similar to that of an engine radiator, and has a large number of cooling air passages 23 formed over almost its entire surface, through which cooling air sent from a cooling fan (not shown) or running air passes. A large number of radiation fins 24 are provided on the outer wall of this passage 23.

The inside of the condenser 220 is separated from the cooling air passage 23 and the like.

It is sealed, and gathering chambers 25 and 26 are formed at its upper and lower parts.

The steam pipe 20 is connected to the gathering chamber 25.
A return pipe 21 is open connected to each of the condensers 22 and 6.
A closed loop cooling path is formed by the steam pipe 20, return pipe 21, and cooler main body 15.

In this case, in the condenser 22, the gathering chamber 26 is the cooler main body 15↓
For example, when applied to a large vehicle, it may be installed in the upper part of the driver's cab.

On the other hand, a vacuum pump 27 is provided as a means for reducing the pressure in the cooling circuit by 2, and its suction side communicates with the collecting chamber 25 above the condenser 22 via a pipe 28.

This vacuum bonder 27 is an electric type, and is F-driven and controlled by a control circuit 29.
Pressure signals from a vacuum sensor (pressure sensor) 30 installed in the gathering chamber 25 and ON/OFF signals of the engine start key 32 are input.

Based on these signals, the control circuit 29 controls the vacuum pump 27 so as to reduce the pressure in the cooling circuit to a predetermined pressure immediately after the engine starts.

In this case, the pressure in the cooling circuit is reduced to, for example, 72txrmHf as shown in Figure 6, and c! ll
The boiling point of the refrigerant filled in the cooler body 15 is set at 45°C.

The system is constructed in this way, and its operation will be explained first.

Immediately after starting the engine, the vacuum bonder 27 is driven in response to a signal from the vacuum sensor 30, and the pressure in the cooling circuit is set to a predetermined pressure (approximately 72 ttanHf).

In this state, when high-temperature intake air pressurized by the supercharger enters the air passage 16iIffi of the cooler main body 15, the refrigerant filled in the cooler main body 15 is heated by the heat from the intake air.

As a result, the temperature of the refrigerant increases.

At this time, the temperature (approximately 45
When the temperature reaches K), the refrigerant begins to boil and evaporates while taking latent heat of vaporization from the intake air.

In other words, by lowering the pressure inside the cooling circuit.

The refrigerant can be boiled at a predetermined low temperature, and therefore, it is possible to sufficiently remove heat from the intake air through extremely large boiling and vaporizing heat.

Since this boiling steam is light, it smoothly flows from the steam distillation section 18η) of the cooler main body 15 through the steam pipe 20 to the condenser 22, where it is cooled by radiating heat by ventilation from a cooling fan, etc. is condensed into a liquid.

The heat dissipation efficiency of this steam in the condenser 22 is extremely good, and therefore even relatively weak ventilation can sufficiently promote cooling and condensation of the steam.

Then, the refrigerant condensed and liquefied here is sent down to the collecting chamber 26vCW of the condenser 22, and passes through the return pipe 21'i to the collecting chamber 26vCW.
．． C! Q can also sufficiently cool the cooler body 15 which is located at a low position, and therefore pressurized intake air can be cooled with a small amount of refrigerant. It becomes possible to easily lower the temperature to a predetermined temperature, for example, 50°C.

As a result, the entire device can be made smaller, a pump for completely circulating the refrigerant is no longer required, and the driving power for the cooling fan is also reduced, ensuring excellent performance as an intercooler.

The vacuum pump 27 is driven in accordance with the signal from the vacuum sensor 30, so if the pressure in the cooling path rises due to a leak, it will be returned to the predetermined pressure and the device will always operate normally during operation. is maintained, but it is preferable to wait for hysteresis to prevent hunting.

FIG. 7 shows an embodiment of the pond according to the present invention, which is suitable for application to a passenger car, etc., when the condenser 22 is installed at the same height as the cooler body 15 or at a position slightly lower than this. A supply pump (electric bonder) 33 is installed in the middle of the return pipe 21 that connects the engine cooling water temperature sensor 31, the condenser 22, and the cooler main body 15, and the liquefied refrigerant from the rainbow condenser 22 is supplied to the bonder 33. The water is sent to the cooler main body 15.

In this case, as shown in FIG. 8, an overflow pipe 34 is installed as a liquid level control means that opens on the side surface of the sea urchin cooler main body 15, and this overflow pipe 34 is connected to a drain pipe 35 provided in parallel with the return pipe 21. It is connected to the lower part of the condenser 22 through the pipe.

The liquefied refrigerant in the condenser 22 is sent to the supply bond 33 to the F-cooler main body 15, but at this time, if the refrigerant liquid level in the cooler main body 15 exceeds the width of the overflow pipe 34, the refrigerant flows through the overflow pipe 34 and the drain pipe 35. The refrigerant is returned to the condenser 22, and therefore the refrigerant liquid level in the cooler body 15 is always maintained at an appropriate level.

The main drain pipe 35 branches off from the overflow pipe 34 and opens into the liquid storage section 19 at the lower part of the cooler main body 15, and an electromagnetic valve 36 is interposed therebetween.

This solenoid valve 36 is connected to the control circuit 37 together with the vacuum 7J5 cylinder 27 that reduces the pressure in the supply pump 33 and the cooling circuit.
ni,,c! ll drive control, and is opened only when the engine is stopped or when the engine is warmed up when the cooling water temperature is low.

That is, from when the engine is stopped to when it is warmed up after starting, the solenoid valve 36? ! By opening 1", the refrigerant sound is stored in the condenser 22 inside the cooler body 15, and the cooler body 15 is kept in an empty state. Therefore, the intake air can be cooled during warm-up operation when the supercharger hardly operates. is avoided, and warm-up performance and cold start performance are greatly improved.

In addition, when the start key is turned on and the 7c engine cooling water temperature is 60℃ or higher, for example, it is determined that the engine should be warmed up and restarted.
The solenoid valve 36 is immediately closed.

On the other hand, the supply bond 33 is driven after the solenoid valve 36 is closed and sends the refrigerant to the sound cooler main body 15 as described above. Under these conditions, there is no need to cool the intake air, so if the drive is stopped, the drive power can be reduced. In addition, in this example as well, as in the previous example, air can be drawn in efficiently using a small wrinkled refrigerant. Can be cooled〃1 etc.
Even if the pump 33 is used in this way, its output and power are originally extremely small compared to, for example, the one in Fig. 3. becomes.

By the way, when the liquid level of the refrigerant in the cooler main body 15 rises, it is returned to the condenser 22 through the overflow pipe 34, so that the refrigerant on the condenser 22 side and the refrigerant on the cooler main body 15 side are always in a mixed flow state. It is in. Therefore, when a mixture of water and antifreeze is used as a refrigerant, only water evaporates and its vapor flows into the condenser 22 from the steam pipe 20.
The quality of the antifreeze liquid in the refrigerant on the condenser 22 side does not deteriorate, and a good rust prevention effect is maintained.

Note that 38 in Figure 1 is a vacuum tank, one of which is connected to the vacuum pump 27 (to the exhaust 1H port of the vacuum pump 27), and the other is connected to the intake manifold, etc. downstream of the throttle valve of the engine (not shown) via the check valve 39. It is connected to the. When idling, etc. when the supercharger does not operate, the vacuum tank 38
The strong suction negative pressure generated downstream of the Vc throttle valve is stored,
This negative pressure is supplemented with the drive of the rainbow vacuum bonder 27. Thereby, the pressure ratio of the vacuum bonder 27 can be reduced.

For example, a small and simple diaphragm type pump can be used.

(Effect of the invention) The boiling point of the refrigerant is lowered, and the large latent heat of boiling and vaporization of the refrigerant is used to cool the pressurized intake air from the supercharger with full efficiency, resulting in a compact intercooler with excellent cooling performance. There is an effect.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a conventional example, FIG. 2 is a graph showing its cooling effect, FIG. 3 is a sectional view of another conventional example, and FIG. 4 is a sectional view of a configuration of an embodiment of the present invention. Figure 5 shows the A-
AM sectional view, FIG. 6 is a graph showing an example of setting the pressure in the circuit, FIG. 7 is a configuration sectional view showing another embodiment of the present invention, and FIG.
The figure is a B-BWB sectional view thereof. 14... Intake passage % 15... Cooler body, 20.
...Steam pipe, 21... Return 9 pipe, 22... Condenser, 2
7... Vacuum bonder, 29... Control circuit, 30...
Vacuum sensor, 31...Cooling water temperature sensor, 32...
・Start key. 33... Supply pump, 34... Overflow pipe. 36... Solenoid valve, 37... Control circuit, 38... Vacuum tank. Patent applicant: Nissan Motor Co., Ltd. Figure 1 Figure 2 Figure 4 3229 3O27 2528 224 2/ A 26 °/8 /6.2 4 19. . C 2119/7 /b

Claims (1)

[Claims] 1. In an intercooler device for a supercharged engine that completely cools pressurized intake air sent from the supercharger to the engine main body via the intake passage, there is a predetermined upper part in the intake passage downstream of the supercharger. The entire cooler body is filled with liquid refrigerant, leaving a space, and the cooler body and the refrigerant condenser are connected through a steam pipe in the upper part through which the refrigerant vapor flows and a return pipe in the lower part to return the condensed refrigerant. 1. An intercooler device for a supercharged engine, characterized in that the intercooler device forms a closed circuit, and further comprises means for completely reducing the pressure within the closed circuit. 2. The intercooler device for a supercharged engine according to claim 1, wherein the pressure reducing means is a vacuum pump provided in a passage communicating with the space. 3. The pressure reducing means operates according to the pressure in the closed loop and the engine start key.Claim 1 (t7C) is an intercooler device for a supercharged engine according to claim 2.