JPS591326B2 - Gas-liquid separation device for internal combustion engine cooling system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for separating gas and liquid during circulation of a coolant as the temperature of the coolant increases and decreases in a cooling system of an internal combustion engine.

In the present invention, the gas-liquid separation device includes an accumulator, a radiator, and a piping system that fluidly connects these two.

For example, in a car, in order to keep the temperature of the engine within a certain range during driving, the coolant that circulates within the engine block is cooled by a radiator and then circulated back into the engine block. It is a method.

However, as the temperature of the coolant increases, dissolved oxygen in the liquid vaporizes and grows into bubbles, reducing the cooling effect of the coolant itself and increasing the pressure within the cooling system.

Therefore, unless the air bubbles are separated from the inside of the cooling system, the engine cannot be effectively cooled, causing overheating.

This gas-liquid separation is carried out in an accumulator installed separately from the radiator. For example, conventionally, as shown in FIG. be.

As shown in Fig. 2, this system supplies cooling liquid to an accumulator 2 using a two-way valve provided in a cap 5 at the mouth.
Alternatively, the accumulator 2 is electrically connected to the radiator 1.

That is, when the temperature in the cooling system rises and the pressure increases, the expanded cooling fluid pushes up the first valve 6 against the spring 7, as shown in FIG. The bubbles flow from the bottom of the accumulator 2 through the liquid, rise from the liquid, accumulate in the upper part of the accumulator, and are released into the atmosphere through a gap provided in the cap 9.

When the temperature of the cooling system decreases, as shown in FIG. 3, the first valve 6 is pressed by the spring 7 to close the gap 8 due to the negative pressure in the cooling system, and the second valve 10 opens the gap 11, causing the accumulator to close. 2
The amount of coolant discharged into the valve body returns to the radiator 1 through a passage 12 and a gap 11 in the valve body.

In this method, the expanded cooling liquid flows into the bottom of the accumulator tank, forms bubbles, and separates gas and liquid.
The gas-liquid separation effect cannot be said to be good at all.

In addition, since two valves are physically arranged on the cap, the structure of the cap becomes complicated, and in the case of large vehicles such as trucks, the radiator 1, Since the engine 13 is disposed below the cabin 14, when replenishing a large amount of coolant to the radiator 1,
The cap 5 must be removed by folding down the cabin 14 or tilting the seat 15 to supply liquid.

In another conventional method, as shown in FIG. 18 is provided with a cap 5 having a two-way valve as described above, and the bottom of the accumulator 2 and the inlet pipe 18 are connected with a hose 19.

As mentioned above, this method also introduces gas and liquid from the bottom of the accumulator 2, so the gas-liquid separation effect is weak, and in terms of structure, the catub structure is the same as that shown in Figures 2 and 3. Therefore, the cap structure becomes complicated, and furthermore, since the inlet pipe 18 and the accumulator 2 are separate bodies, a wider installation space and a hose for connecting the accumulator and the radiator are required.

Furthermore, in both of these types, the cap, inlet pipe, and other parts are made of expensive stainless steel material from the standpoint of rust prevention, which inevitably increases the cost of the device.

In view of the above, it is an object of the present invention to solve the above-mentioned problems by making it possible to effectively perform gas-liquid separation in a cooling system using a simple device.

In other words, the gist of this invention is that an inlet pipe is integrated into the accumulation tank, and two valve bodies are installed separately at the upper and lower parts of the tank, so that gas and liquid from the radiator are discharged by falling into the tank from above. This system is particularly suitable for large vehicles such as trucks, in which gas and liquid are separated, and when the cooling system pressure is lowered, the cooling liquid is supplied from the lower part of the tank to prevent air from entering.

The method of this invention will be explained below using an embodiment of the apparatus shown in FIG. 6 and subsequent figures.

In FIG. 6, 1 is a radiator, 20 is an accumulator made of plastic material, 21 is a radiator hose, and 22 is an overflow hose.

As shown in FIG. 7, the accumulator 20 has an (accumulator) tank 23 that passes through openings 24 and 25 formed at the top and bottom, and has an inlet pipe 26 inside.
or integrated into it.

An outer cylinder part 28 having a flange 27 is integrally formed on the upper part of the inlet pipe 26, and between it and an inner cylinder part 29,
A passage 30 is formed so that the coolant can be discharged from the inlet pipe 26 into the tank 23.

The flange 27 is fitted between the flanges 7 of the upper opening 24 of the tank to allow ventilation into and out of the tank.

The outer cylindrical portion 28 is provided with a screw on the outer periphery of the outer cylindrical opening that protrudes beyond the upper end opening of the inner cylindrical portion 29, and a radiator cap (hereinafter referred to as a cap) 32 provided with a first valve 31 is screwed into the outer cylindrical portion 28.

The cap 32 has a first valve 31 on a shaft protruding from the center of the bottom surface.
A push spring 33 is interposed between the bottom surface of the cap and the first valve 31, so that the first valve 31 always seals the upper end opening of the inner cylindrical portion 29.

The inner cylindrical portion 29 has a nipple 34 protruding from the lower side of the upper opening, and is connected to the radiator 1 via an overflow hose 22.

A flange 35 is formed at the bottom of the inlet pipe 26, and a gasket 36 is formed between the flange and the inner bottom surface of the tank.
is sealed liquid-tight through the

In the inlet pipe, a sleeve 37 is installed horizontally outward in a portion near the bottom of the tank, and the sleeve 37 is horizontally installed outward, and a conduction port 3 is provided on the wall surface of the inlet pipe within the sleeve 37.
8 is open.

A cap 4 having a communication hole 39 is provided at the mouth of the sleeve 37.
0 is screwed together through a seat 41, and a second valve 42 is provided in the sleeve 37 through a spring 43, and normally the second valve 42
The communication hole 39 is sealed by a spring 43.

The lower end of the inlet pipe 26 that protrudes outward from the bottom of the tank is connected to the upper end of the radiator hose 21 described above.

Note that 44 is a replenishment port provided at the top of the tank, and 45 is a discharge port, each of which is sealed with a cap.

As shown in FIG. 4, this accumulator 20 is located above the radiator 1 and engine 13 installed below the cabin, and is connected to the cabin via a bracket 46.
4 Installed externally.

Next, this invention will be explained in detail.

Normally, the inlet pipe 26 in the tank 23 is filled with coolant, and the first valve 31 and the second valve 42 are spring-forced to prevent the coolant in the inlet pipe from flowing into the tank.

When the engine is driven, the coolant circulates through the water jacket and the radiator, and the coolant that cooled the engine is cooled by the radiator.

However, as the temperature inside the cooling system rises, the air mixed in the coolant turns into bubbles, and even if the radiator cools it, the bubbles inhibit the cooling effect, causing the coolant temperature to rise and the engine cooling effect becomes worse.

As the bubbles grow, the cooling liquid expands, increasing the pressure within the cooling system.

When the pressure in the cooling system becomes higher than the pressure set by the first valve 31 (spring 33) of the accumulator 20, the first valve 31 opens and the second valve 42 opens by the spring 43, as shown in FIG. With the communication port 39 closed, the coolant flows into the inlet pipe 26 through the radiator hose 21 and overflow hose 22, overflows from the upper end opening of the inner cylinder part 29, and falls into the tank 23 through the passage 30 and is discharged. The air bubbles in the coolant are easily separated by this falling action.
Air accumulates in the upper part of the tank and is released to the atmosphere through a ventilation path (not shown) provided between the opening flange of the tank and the flange 27 of the inlet pipe outer cylinder, and the air inside the radiator is removed and cooled. Recover the effect.

When the temperature inside the cooling system drops due to engine stoppage, etc., the inside of the system becomes negative pressure, and the first valve 31 seals the upper end opening of the inner cylindrical part of the inlet pipe with the spring 33, and the air flows into the inlet pipe. The spring 43 of the second valve 42 is compressed by the negative pressure, and the communication port 39 is opened.
The amount of coolant discharged to the accumulator 20 due to the temperature rise is transferred to the radiator hose 21 from the inlet pipe 26 through the communication hole 39, the sleeve 37, and the communication hole 38.
The water is then returned to the radiator 1 through the overflow hose 22.

When the coolant is returned from the tank 23 to the radiator, the second valve 42 submerged in the liquid in the tank 23 is used to prevent air from entering the coolant.

To replenish the coolant into the tank 23, remove the cap from the replenishment opening 44 at the top of the tank, and when replenishing a large amount of coolant to the radiator, remove the cap from the refill opening 44.
Just remove it and inject it from the opening of the inlet pipe.

As another example, the connection between the radiator hose 21 and the radiator 1 may be such that the radiator hose 21 is connected to the bottom of the radiator 1.

Furthermore, the second valve 42 may not be provided on the inlet pipe 26, but may be provided on the bottom of the tank 23, and the second valve and the radiator hose may be connected by another pipe or hose.

Since the gas-liquid separation device for an internal combustion engine cooling system of the present invention has the above-described configuration, the second
The height of the radiator is required to keep the water head difference between the inlet pipe (C cooling system) which the valve receives and the accumulator side - if the water head difference is large, the second valve will not operate even if the pressure in the cooling system drops - to below a predetermined value. There is no need to take this into consideration, and the accumulator can be designed at a height that takes into account the falling height required for gas-liquid separation and the height required for submerging the second valve from the upper end opening of the inlet pipe.

Therefore, according to the present invention, the accumulator can be made smaller, and in combination with the fact that the inlet pipe is integrally provided inside the accumulator tank, the space occupied by the internal combustion engine cooling system can be significantly reduced.

In addition, in a system in which the accumulator is integrally installed on the side of the radiator and the cooling liquid is returned to the bottom of the radiator, in order to reduce the above-mentioned water head difference to a predetermined value or less, the water head in the accumulator must be close to that in the radiator. Therefore, it is difficult to downsize the accumulator.

[Brief explanation of drawings]

Fig. 1 is a conceptual diagram showing an example of a conventional cooling system gas-liquid separator, Fig. 2 is a structural diagram of a valve body in a conventional gas-liquid separator, and is a sectional view showing the state during gas-liquid separation. Similarly, a partial cross-sectional view of the valve body during cooling liquid recirculation, FIG. 4 is a schematic diagram of the cooling system shown in FIG. 1 mounted on a vehicle, and FIG. 5 is a conceptual diagram showing another conventional cooling system gas-liquid separation device. , FIG. 6 and subsequent figures show an embodiment of the present invention, FIG. 6 is a conceptual diagram of a cooling system gas-liquid separation device, FIG. 7 is a sectional view of an accumulator of the gas-liquid separation device,
FIG. 8 is a cross-sectional view of the main part of the accumulator during gas-liquid separation, and FIG. 9 is a cross-sectional view of the main part of the accumulator during recirculation of the cooling liquid. 1...Radiator, 20...Accumulator, 21...Radiator hose, 22...
... Overflow hose, 23 ... Tank, 26 ... Inlet pipe, 31 ...
・First valve, 32...Radiator cap, 42
...Second valve.

Claims (1)

[Claims] 1. In a gas-liquid separation device equipped with an accumulator, which is applied to an internal combustion engine cooling system in which an inlet pipe is connected above a radiator via a radiator hose, an inlet is provided inside the accumulator tank 23. pipe 2
A first valve 31 for communicating with the inside of the accumulator tank 23 by increasing the pressure in the cooling system is attached to the radiator cap 32, which is integrally installed through the radiator cap 32 and is fitted into the upper end opening of the inlet pipe 26, The gas-liquid separation device for an internal combustion engine cooling system is further characterized in that a second valve 42 is provided at a position where the inlet pipe 26 is immersed in the cooling liquid in the accumulator tank 23 and opens when the pressure in the cooling system decreases.