JP2003269824A - Gas-liquid separator for ejector cycle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To positively separate a gas-phase refrigerant, a liquid-phase refrigerant and refrigerator oil in a gas-liquid separator for an ejector cycle. <P>SOLUTION: A liquid-phase refrigerant outflow port 54 and an oil return hole 55 are provided on the lower side than an inflow port 52, and a gas-phase refrigerant outflow port 53 is provided on the higher side than the liquid-phase refrigerant outflow port 54 and the oil return hole 55. The liquid-phase refrigerant outflow port 54 is provided on the higher side than the oil return hole 55. The tank cross-sectional area S1 of a large diameter part 51a provided with the liquid-phase refrigerant outflow port 54 and oil return hole 55, out of a tank body 51 is made larger than the tank cross-sectional area S2 of a small diameter part 51b provided with the inflow port 52, out of the tank body 51, and a shielding plate 56 is provided above the liquid level. Consequently, the gas-phase refrigerant, liquid-phase refrigerant and refrigerator oil are positively separated. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas-liquid separator for an ejector cycle.

[0002]

As is well known, the ejector cycle is a well-known ejector cycle in which a refrigerant is decompressed and expanded by an ejector to suck a vapor phase refrigerant evaporated in an evaporator and expansion energy is converted into pressure energy. It is a refrigerating cycle in which the suction pressure of the compressor is increased by converting into.

That is, in the ejector cycle, the refrigerant flow circulates in the order of compressor → radiator → ejector → gas-liquid separator → compressor, and circulates in the order of gas-liquid separator → evaporator → ejector → gas-liquid separator. There is a refrigerant flow, the gas-liquid separator separates the refrigerant flowing out of the ejector into a gas-phase refrigerant and a liquid-phase refrigerant, supplies the gas-phase refrigerant to the suction side of the compressor, and evaporates the liquid-phase refrigerant. Supply to the side.

At this time, in order to prevent liquid compression from occurring in the compressor, ideally it is desirable to supply only the gas-phase refrigerant, that is, the saturated gas, from the gas-liquid separator to the compressor. When liquid compression occurs in the compressor, the discharge temperature and the discharge pressure are excessively increased, the life of the compressor is shortened, and the power consumption of the compressor is increased.

On the other hand, if a large amount of refrigerating machine oil flows into the evaporator together with the liquid-phase refrigerant, the refrigerating machine oil may adhere to the inner surface of the evaporator and a large amount of refrigerating machine oil may stay in the evaporator. is there.

When the refrigerating machine oil adheres to the inner surface of the evaporator, the heat transfer coefficient between the liquid-phase refrigerant and the evaporator is reduced, which hinders the evaporation of the liquid-phase refrigerant and reduces the heat exchange efficiency of the evaporator. At the same time, the cross-sectional area of the refrigerant passage is substantially reduced to decrease the flow rate of the refrigerant flowing in the evaporator, and in response to this, the heat absorption capacity of the evaporator is decreased.

Further, since the refrigerating machine oil stays in the evaporator, there is a possibility that the compressor may lack the refrigerating machine oil, that is, the lubrication may be insufficient.

In view of the above points, an object of the present invention is to provide a gas-liquid gas-liquid separator having a novel structure different from the conventional one, which can separate a gas-phase refrigerant, a liquid-phase refrigerant and a refrigerating machine oil. To do.

[0009]

In order to achieve the above object, the present invention provides a compressor (1
Radiator (2) that cools the high-pressure refrigerant compressed by
0), an evaporator (30) for evaporating a low-pressure refrigerant, a nozzle for converting pressure energy of the refrigerant flowing out of the radiator (20) into velocity energy to expand the refrigerant under reduced pressure, and a refrigerant injected from the nozzle for evaporation. The ejector (40) is provided with an ejector (40) having a pressure increasing unit for converting velocity energy into pressure energy and increasing the pressure of the refrigerant while mixing with the refrigerant sucked from the container (30). A gas-liquid separator that separates the refrigerant that has flowed out of the refrigerant into a gas-phase refrigerant and a liquid-phase refrigerant, supplies the gas-phase refrigerant to the suction side of the compressor (10), and supplies the liquid-phase refrigerant to the evaporator (30) side. The inflow part (52) into which the refrigerant flowing out of the ejector (40) flows, the gas-phase refrigerant outflow part (53) to outflow the gas-phase refrigerant, and the liquid-phase refrigerant outflow part (54 to outflow the liquid-phase refrigerant). , And a tank main body (51) provided with an oil return part (55) for letting out refrigerating machine oil, and centrifugally separates a gas phase component and a liquid phase component mainly on the upper side of the tank main body (51). On the other hand, on the other hand, it is characterized in that the liquid phase refrigerant and the refrigerating machine oil are mainly separated by specific gravity at the lower side of the tank body (51).

As a result, it is possible to obtain a gas-liquid gas-liquid separator having a novel structure different from the conventional one, which can separate the gas-phase refrigerant, the liquid-phase refrigerant and the refrigerating machine oil.

According to the second aspect of the invention, the tank cross-sectional area (S1) at the portion of the tank body (51) where the liquid-phase refrigerant outflow portion (54) is provided is the tank body (5).
It is characterized in that it is larger than the tank cross-sectional area (S2) in the part of 1) where the inflow part (52) is provided.

As a result, the refrigerant flowing from the portion having a small tank cross-sectional area to the portion having a large tank cross-sectional area lowers its swirling speed, and thus stabilizes the liquid surface of the liquid-phase refrigerant accumulated in the gas-liquid separator. be able to.

Therefore, since the liquid-phase refrigerant and the refrigerating machine oil can be reliably separated from each other in specific gravity, the liquid-phase refrigerant can be stably supplied to the evaporator (30) and the amount of the enclosed refrigerant can be reduced. You can As a result, the manufacturing cost of the ejector cycle can be reduced.

According to the third aspect of the present invention, the liquid-phase refrigerant outflow portion (54) and the oil return portion (55) are provided on the upper side.
An inflow suppression member (56) is provided to prevent the refrigerant flowing into the tank body (51) from directly flowing into the liquid-phase refrigerant outflow portion (54) and the oil return portion (55). It is characterized by

As a result, the liquid surface of the liquid-phase refrigerant accumulated in the gas-liquid separator can be further stabilized, so that the liquid-phase refrigerant and the refrigerating machine oil can be reliably separated by specific gravity.

In the invention according to claim 4, the inflow suppressing member (56) is provided with deceleration means (56a) for decelerating the refrigerant flowing so as to swirl in the tank body (51). And

As a result, the swirling speed of the refrigerant flowing from the portion having a small tank cross-sectional area to the portion having a large tank cross-sectional area can be surely reduced, so that the liquid level of the liquid-phase refrigerant accumulated in the gas-liquid separator can be reduced. The liquid-phase refrigerant and the refrigerating machine oil can be reliably separated from each other by the specific gravity.

When the density of the liquid-phase refrigerant is lower than the density of the refrigerating machine oil, the liquid-phase refrigerant outflow portion (54) is located above the oil return portion (55) as in the fifth aspect of the invention. It is desirable to locate it.

Incidentally, when a refrigerating machine oil having a density smaller than that of the liquid-phase refrigerant is adopted, the oil return section (5
It is desirable to position 5) above the liquid-phase refrigerant outlet (54).

In the invention described in claim 6, the compressor (1
Radiator (2) that cools the high-pressure refrigerant compressed by
0), an evaporator (30) for evaporating a low-pressure refrigerant, a nozzle for converting pressure energy of the refrigerant flowing out of the radiator (20) into velocity energy to expand the refrigerant under reduced pressure, and a refrigerant injected from the nozzle. The refrigerant that has flowed out from the ejector (40) and the ejector (40) that has a pressure increasing unit that increases the pressure of the refrigerant by converting velocity energy into pressure energy while mixing the refrigerant sucked from the evaporator (30) The liquid phase refrigerant is separated into a liquid phase refrigerant and a gas phase refrigerant is supplied to the suction side of the compressor (10), and a liquid phase refrigerant is supplied to the evaporator (30) side. And a gas-liquid separator (50) according to item 1, wherein the high-pressure refrigerant is
It is characterized in that the refrigerant is pressurized to above the critical pressure.

As a result, the ejector cycle can be operated efficiently.

In the seventh aspect of the invention, the refrigerant may be carbon dioxide.

Incidentally, the reference numerals in the parentheses of the above-mentioned means are examples showing the correspondence with the concrete means described in the embodiments described later.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION In this embodiment, the ejector cycle according to the present invention is applied to an air conditioner, and FIG. 1 is a schematic diagram of the ejector cycle according to the present embodiment.

The compressor 10 sucks and compresses the refrigerant, and the condenser 20 exchanges heat between the refrigerant discharged from the compressor 10 and the outdoor air and releases the heat absorbed by the refrigerant to the high pressure side heat exchanger. Is. Incidentally, in the present embodiment, CFC (R404) is used as the refrigerant, but it goes without saying that carbon dioxide may be used as the refrigerant.

When chlorofluorocarbon is used as the refrigerant, the refrigerant is condensed in the condenser 20, but when carbon dioxide is used as the refrigerant, the pressure of the high-pressure side refrigerant becomes equal to or higher than the critical pressure of the refrigerant, Moreover, since the refrigerant has a temperature distribution such that the refrigerant temperature does not condense in the condenser 20 and decreases from the refrigerant inlet side toward the refrigerant outlet side, the condenser 20 functions as a radiator.

The evaporator 30 is a low-pressure heat exchanger that heat-exchanges the air blown out into the room with the liquid-phase refrigerant to evaporate the liquid-phase refrigerant to evaporate the refrigerant and absorb heat from the air. The ejector 40 is A nozzle for expanding the refrigerant under reduced pressure,
In addition, the decompression unit is configured to have a pressure increasing unit including a mixing unit and a diffuser for sucking the vapor phase refrigerant evaporated in the evaporator 30 and converting the expansion energy into pressure energy to increase the suction pressure of the compressor 10. And the pump means.

The gas-liquid separator 50 is a gas-liquid separating means for storing the refrigerant by separating the inflowing refrigerant into the gas-phase refrigerant and the liquid-phase refrigerant while the refrigerant flowing out from the ejector 40 flows in. The gas-phase refrigerant outlet of the compressor 50 is the compressor 10
Of the liquid phase refrigerant is connected to the inflow side of the evaporator 30.

Next, the structure of the gas-liquid separator 50 will be described.

FIG. 2 is a schematic diagram of the gas-liquid separator 50. The tank main body 51 has an inflow port 52 which forms an inflow part into which the refrigerant flowing out of the ejector 40 flows, and a gas-phase refrigerant outflow part which allows the gas-phase refrigerant to flow out. A gas-phase refrigerant outlet port 53, a liquid-phase refrigerant outlet port 54 for forming a liquid-phase refrigerant outlet,
Also, the refrigerant container is provided with an oil return hole 55 that forms an oil return portion for letting out refrigeration oil.

The liquid refrigerant outlet 54 and the oil return hole 55 are provided below the inlet 52, and the gas refrigerant outlet 53 is the liquid refrigerant outlet 54 and the oil return hole 55.
The liquid-phase refrigerant outlet port 54 is provided above the oil return hole 55.

The inflow port 52 is, as shown in FIG.
The refrigerant flowing into the small diameter portion 51b is opened in the tangential direction of the inner circumferential wall of the small diameter portion 51b so that the refrigerant swirls in the small diameter portion 51b.

Further, a large diameter portion 51a of the tank body 51 in which the liquid-phase refrigerant outlet 54 and the oil return hole 55 are provided.
2, the tank cross-sectional area S1 is larger than the tank cross-sectional area S2 of the small diameter portion 51b of the tank body 51 in which the inflow port 52 is provided.

As shown in FIG. 2, above the liquid-phase refrigerant outlet 54 and the oil return hole 55, the refrigerant that has flowed into the tank body 51 directly flows into the liquid-phase refrigerant outlet 54 and A shield plate 56 is provided as an inflow suppressing member for suppressing the inflow to the oil return hole 55 side, and the upper surface side of the shield plate 56 swirls in the tank body 51 as shown in FIG. A deceleration blade 56a is integrally formed as a deceleration means for decelerating the flowing refrigerant.

The tank body 51 is made of a material having excellent workability, and in this embodiment, an aluminum alloy is used.

Next, the function and effect of the gas-liquid separator 50 according to this embodiment will be described.

The refrigerant flowing from the inlet 52 into the tank main body 51 is on the upper side of the tank main body 51, that is, the small diameter portion 51.
The gas phase component and the liquid phase component are mainly centrifugally separated in b, and the liquid phase refrigerant and the refrigerating machine oil are mainly gravity-separated in the lower side of the tank main body 51, that is, the large diameter part 51a.

Here, the term "centrifugal separation" means that a refrigerant containing a refrigerating machine oil is swirled so that a centrifugal force acting on a liquid phase component (liquid phase refrigerant and refrigerating machine oil) and a centrifugal force acting on a gas phase component (gas phase refrigerant). The separation is performed by utilizing the difference between the force and the gravity separation, and the specific gravity separation is performed by utilizing the difference between the gravity acting on the liquid-phase refrigerant and the gravity acting on the refrigerating machine oil.

The liquid phase component having a density higher than that of the gas phase component spirally flows downward along the inner peripheral wall of the tank main body 51 at a swirling speed higher than that of the gas phase component, and the gas phase component is The gas-phase refrigerant outlet 53 flows out to the compressor 10 side.

At this time, since the tank cross-sectional area S1 in the large diameter portion 51a is larger than the tank cross-sectional area S2 in the small diameter portion 51b, the small diameter portion 51b to the large diameter portion 5
The refrigerant flowing into 1a reduces its swirling speed.

Therefore, since the liquid surface of the liquid-phase refrigerant accumulated in the gas-liquid separator 50 can be stabilized, the liquid-phase refrigerant and the refrigerating machine oil can be reliably separated by specific gravity. In addition, since the liquid-phase refrigerant can be stably supplied to the evaporator 30, the amount of the enclosed refrigerant can be reduced and the manufacturing cost of the ejector cycle can be reduced.

Further, the refrigerant that has flowed into the tank main body 51 by the shield plate 56 is surely suppressed from directly flowing into the liquid-phase refrigerant outlet port 54 and the oil return hole 55 side. The liquid level of the liquid-phase refrigerant accumulated in the separator 50 can be further stabilized, and the specific gravity of the liquid-phase refrigerant and the refrigerating machine oil can be reliably separated.

Further, the shield plate 56 is provided with a reduction blade 56a.
Is provided, the small diameter portion 51b to the large diameter portion 51a
Since the swirling speed of the refrigerant flowing into the can be reliably reduced, the liquid level of the liquid-phase refrigerant accumulated in the gas-liquid separator 50 can be further stabilized, and the liquid-phase refrigerant and the refrigerating machine oil can be reliably retained. Specific gravity can be separated.

(Other Embodiments) In the above-described embodiments, the present invention is applied to the air conditioner, but the present invention is not limited to this and can be applied to a water heater, a refrigerator and the like.

Further, the shielding plate 56, especially the reduction blade 56
The shape of a is not limited to the shape shown in FIG. 4, and may be any shape that can reduce the speed of the refrigerant.

Further, in the above-mentioned embodiment, the cross-sectional area of the tank main body 51 changes in a stepped manner, but the present invention is not limited to this, and the tank goes down toward the lower side. A conical flask-shaped tank body 51 that increases the cross-sectional area S may be adopted.

The refrigerant is not limited to carbon dioxide and chlorofluorocarbon, and may be a hydrocarbon refrigerant, a natural refrigerant such as nitrogen, or a mixed refrigerant.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an ejector cycle according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of a gas-liquid separator according to an embodiment of the present invention.

FIG. 3 is a top view of the gas-liquid separator according to the embodiment of the present invention.

FIG. 4 is a two-sided view of the shielding plate according to the embodiment of the present invention.

[Explanation of symbols]

50 ... Gas-liquid separator, 51 ... Tank body, 52 ... Inflow port,
53 ... Gas-phase refrigerant outlet 53, 54 ... Liquid-phase refrigerant outlet, 55 ... Oil return hole, 5
6 ... Shield version.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shinya Kato             1-1, Showa-cho, Kariya city, Aichi stock market             Inside the company DENSO

Claims (7)

[Claims] 1. A radiator (20) for allowing a high-pressure refrigerant compressed by a compressor (10) to cool, an evaporator (30) for evaporating a low-pressure refrigerant, and the radiator (20) flowing out. A nozzle that converts pressure energy of the refrigerant into velocity energy to expand the refrigerant under reduced pressure, and a refrigerant that is injected from the nozzle and the evaporator (3
0) and an ejector (40) having a pressure increasing unit for increasing the pressure of the refrigerant by converting velocity energy into pressure energy while mixing with the refrigerant, and the ejector cycle is applied from the ejector (40). Gas-liquid separation in which the discharged refrigerant is separated into a gas-phase refrigerant and a liquid-phase refrigerant, the gas-phase refrigerant is supplied to the suction side of the compressor (10), and the liquid-phase refrigerant is supplied to the evaporator (30) side. And an inflow part (52) into which the refrigerant flowing out of the ejector (40) flows, a gas-phase refrigerant outflow part (53) to outflow the gas-phase refrigerant, and a liquid-phase refrigerant outflow part to outflow the liquid-phase refrigerant ( 5
4) and an oil return part (55) for letting out refrigerating machine oil
A tank main body (51) provided with, and mainly at the upper side of the tank main body (51), a gas phase component and a liquid phase component are centrifugally separated, while the tank main body (5
A gas-liquid separator for an ejector cycle, characterized in that the liquid phase refrigerant and the refrigerating machine oil are mainly subjected to specific gravity separation on the lower side of 1). 2. A tank cross-sectional area (S1) at a portion of the tank body (51) where the liquid-phase refrigerant outflow portion (54) is provided is the inflow portion (52) of the tank body (51). 2. The gas-liquid separator for an ejector cycle according to claim 1, wherein the tank cross-sectional area (S2) at a portion where is provided is large. 3. The refrigerant flowing into the tank body (51) is directly above the liquid phase refrigerant outflow section (54) and the oil return section (55). The gas-liquid separation for an ejector cycle according to claim 1, further comprising an inflow prevention member (56) for suppressing inflow to the outflow portion (54) and the oil return portion (55) side. vessel. 4. The deceleration member (56) is provided with a deceleration means (56a) for decelerating the refrigerant flowing so as to swirl in the tank body (51). A gas-liquid separator for the ejector cycle according to 1. 5. The ejector according to any one of claims 1 to 4, wherein the liquid-phase refrigerant outflow portion (54) is located above the oil return portion (55). Gas-liquid separator for cycles. 6. A radiator (20) for cooling the high-pressure refrigerant compressed by a compressor (10), an evaporator (30) for evaporating a low-pressure refrigerant, and an outflow from the radiator (20). A nozzle for converting pressure energy of the formed refrigerant into velocity energy to expand the refrigerant under reduced pressure, a refrigerant injected from the nozzle and the evaporator (3
0), the ejector (40) having a pressure increasing unit for increasing the pressure of the refrigerant by converting velocity energy into pressure energy while mixing with the refrigerant, and the refrigerant flowing out from the ejector (40) is a vapor phase refrigerant. The liquid phase refrigerant is supplied to the suction side of the compressor (10), and the liquid phase refrigerant is supplied to the evaporator (30) side. The gas-liquid separator (50) according to claim 5, wherein the high-pressure refrigerant is pressurized to a pressure equal to or higher than the critical pressure of the refrigerant. 7. The ejector cycle according to claim 6, wherein the refrigerant is carbon dioxide.