JPH07248163A - Air conditioner - Google Patents

Abstract

PURPOSE:To suppress rising of a discharge temperature of a compressor by early evaporating refrigerant liquid accumulated in an accumulator at the time of starting an air conditioner and to prevent generation of abnormal sound by reducing a flowing speed of high temperature and high pressure gas. CONSTITUTION:The air conditioner comprises a compressor 11 for compressing low temperature and low pressure gas to generate high temperature and high pressure gas, a first heat exchanger 12 (or 16) for radiating heat of the high temperature and high pressure gas compressed by the compressor 11 to condense it to generate high temperature and high pressure liquid, an expansion valve 15 for expanding the high temperature and high pressure liquid generated by the exchanger 12 to generate low temperature and low pressure liquid, and a second heat exchanger 16 (or 12) for absorbing heat of the low temperature and low pressure liquid generated by the valve 15 to evaporate it to generate low temperature and low pressure gas. The conditioner 10 also comprises an accumulator 17 for storing the low temperature and low pressure gas generated by the exchanger 16 and supplying it to the compressor 11, and a high temperature gas bypass circuit 19 for supplying the high temperature and high pressure gas compressed by the compressor 11 to the accumulator 17.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner.

[0002]

2. Description of the Related Art Generally, an air conditioning system of a type in which a compressor is driven by an electric motor (hereinafter referred to as "EHP") is in widespread use. However, this system has a drawback that electricity cost is high and maintenance cost is high. ing. In order to solve this drawback, the type (hereinafter referred to as GHP) in which a compressor is driven by a gas engine using city gas, LP gas, etc.
It is becoming popular in place of HP. Since this GHP can utilize the exhaust heat of the engine, it can perform speed heating.

The above-mentioned EHP and GHP air conditioners have the same basic structure and basic cooling / heating cycle.

A refrigerant circuit having a compressor, an indoor heat exchanger, an expansion valve, an outdoor heat exchanger, and an accumulator is used as a basic structure. Here, the accumulator is for accumulating a part of the refrigerant liquid in the low-temperature low-pressure gas-liquid existing in the low-pressure line on the downstream side of the expansion valve immediately after the start, and a part of the refrigerant liquid is compressed immediately after the start. It is possible to prevent it from being inhaled by the machine.

In the cooling cycle, first, the high-temperature high-pressure gas from the compressor is supplied to the outdoor heat exchanger, which serves as a condenser, via the four-way switching valve, is condensed in the outdoor heat exchanger, and is heated to a high temperature. It becomes a high-pressure liquid. This high-temperature high-pressure liquid becomes a low-temperature low-pressure gas-liquid two-phase by an expansion valve, is supplied to an indoor heat exchanger that serves as an evaporator, and evaporates to become a low-temperature low-pressure gas.

As a result, heat is absorbed from the room to cool the room. Finally, the cold low pressure gas is returned to the compressor via the accumulator. Cooling is performed by repeating the above cycle.

In the heating cycle, first, the high-temperature high-pressure gas from the compressor is supplied via the four-way switching valve to the indoor heat exchanger, which serves as a condenser, and is condensed into a high-temperature high-pressure liquid.
Thereby, heat is released into the room to heat the room. This high-temperature high-pressure liquid is cooled by low temperature and low pressure by the expansion valve.
The low-temperature low-pressure gas is supplied to the outdoor heat exchanger, which becomes the phase, and becomes the low-temperature low-pressure gas, which is returned to the compressor via the accumulator. Heating is performed by repeating the above cycle.

In the air conditioner described above, since the inside of the refrigerant circuit is not warmed when the air conditioner is started, an excessive amount of the refrigerant liquid exists in the refrigerant circuit on the downstream side of the expansion valve, and the excessive refrigerant liquid is stored in the accumulator. Collect. As a result, the amount of refrigerant gas is temporarily reduced, and the pressure in the low-pressure line of the refrigerant circuit from the downstream side of the expansion valve to the suction side of the compressor temporarily decreases. This may reduce the durability of the compressor.

Therefore, conventionally, as a technique for suppressing the temporary decrease in the pressure of the low pressure line at the time of starting, the compressed high temperature high pressure gas is supplied to the low pressure of the refrigerant circuit from the downstream side of the expansion valve to the suction side of the compressor. It is known that a high temperature gas bypass circuit for pressure-feeding a line and a bypass valve provided in the middle of the high temperature gas bypass circuit for opening and closing the high temperature gas bypass circuit are provided (for example, Mitsubishi Electric Corporation announced in 1993). See "Technical data for slim air conditioners"). Here, the high temperature gas bypass circuit is connected to the low pressure line (that is, the low pressure side pipe) of the refrigerant circuit in order to facilitate the connectivity.

[0010]

However, since the high-temperature gas bypass circuit is connected to the low-pressure line of the refrigerant circuit (that is, the low-pressure side pipe) in this case, the refrigerant liquid accumulated in the accumulator at the time of starting the air conditioner is removed. It takes more time to evaporate. As a result, it is not possible to quickly suppress the pressure drop in the low pressure line of the refrigerant circuit. This may impair the durability of the compressor.

Further, since the high-temperature high-pressure gas compressed by the compressor is pressure-fed to the low-pressure line via the high-temperature gas bypass circuit, the flow velocity of the high-temperature high-pressure gas increases due to the pressure difference, which may cause abnormal noise. There is.

Therefore, according to the present invention, when the air conditioner is started, the refrigerant liquid accumulated in the accumulator is evaporated more quickly to suppress the pressure drop in the low pressure line of the refrigerant circuit more quickly and to reduce the flow velocity of the high temperature high pressure gas. It is a technical issue to prevent the generation of abnormal noise.

[0013]

The technical means (hereinafter referred to as the first technical means) taken in the invention of claim 1 in order to solve the above technical problem is to connect a high temperature gas bypass circuit to an accumulator. That is what I did. Specifically, a compressor that compresses low-temperature low-pressure gas to generate high-temperature high-pressure gas, and a first heat exchange that generates high-temperature high-pressure liquid by radiating and condensing the high-temperature high-pressure gas compressed by the compressor. Low-temperature low-pressure gas by absorbing heat and evaporating the low-temperature low-pressure liquid generated by the expansion valve and the expansion valve that expands the high-temperature high-pressure liquid generated by the first heat exchanger to generate low-temperature low-pressure liquid Of a second heat exchanger for generating the high temperature, an accumulator for storing the low temperature low pressure gas generated in the second heat exchanger and supplying it to the compressor, and a high temperature supplying the high temperature high pressure gas compressed by the compressor to the accumulator And a gas bypass circuit.

In order to solve the above technical problems, a second aspect is provided.
The technical means (hereinafter referred to as the second technical means) taken in the invention of (1) is to bring the high temperature gas bypass circuit into thermal contact with the refrigerant liquid accumulated in the accumulator.

In order to solve the above technical problems, a third aspect of the present invention is provided.
The technical means taken in the invention (hereinafter referred to as the third technical means) is that the exposed portion of the high temperature gas bypass circuit into the accumulator has an annular shape.

[0016]

According to the first technical means, since the high temperature gas bypass circuit is connected to the accumulator, the high temperature high pressure gas compressed by the compressor when the air conditioner is started is supplied into the accumulator and accumulated in the lower part of the accumulator. Immediately evaporate excess refrigerant liquid. As a result, the time required to evaporate the excess refrigerant liquid accumulated in the lower part of the accumulator is significantly shortened compared to the conventional technology, and the pressure in the low pressure line of the refrigerant circuit from the expansion valve to the suction side of the compressor is reduced. Can be suppressed faster.

Further, since the high temperature gas bypass circuit is connected to the accumulator, the high temperature and high pressure gas supplied to the accumulator through the high temperature gas bypass circuit is dispersed in the accumulator to reduce its flow velocity, which causes abnormal noise. Can be suppressed.

According to the second technical means, since the high temperature gas bypass circuit is brought into thermal contact with the refrigerant liquid accumulated in the accumulator, the high temperature high pressure gas which has passed through the high temperature gas bypass circuit at the time of starting the air conditioner is stored in the accumulator. It makes the evaporation of the excess refrigerant liquid accumulated in the lower part more active. That is,
The time required to evaporate the excess refrigerant liquid accumulated in the lower part of the accumulator is further shortened, and the pressure drop in the low pressure line of the refrigerant circuit can be suppressed more quickly. Here, while the high temperature high pressure gas passing through the high temperature gas bypass circuit is in thermal contact with the refrigerant liquid accumulated in the lower part of the accumulator, the energy of the high temperature high pressure gas is used to evaporate the refrigerant liquid. It is also possible to suppress an increase in the temperature of the discharge gas.

Further, since the high temperature gas bypass circuit is brought into thermal contact with the refrigerant liquid accumulated in the accumulator, the high temperature high pressure gas supplied to the accumulator through the high temperature gas bypass circuit becomes excessive refrigerant liquid accumulated in the lower part of the accumulator. The flow velocity of the high-temperature high-pressure gas is further reduced due to the collision, so that the generation of abnormal noise can be reliably prevented.

According to the third technical means, since the exposed portion of the high temperature gas bypass circuit to the inside of the accumulator has an annular shape, the contact area between the high temperature gas bypass circuit and the inside of the accumulator increases, and the accumulator is increased. To make the evaporation of the excess refrigerant liquid that has accumulated more actively. In this configuration, if the high temperature gas bypass circuit is connected to the refrigerant liquid in the accumulator as in the second technical means, the contact area between the high temperature gas bypass circuit and the refrigerant liquid accumulated in the lower portion of the accumulator increases and the accumulator accumulates. In addition, the evaporation of excess refrigerant liquid is made even more active. As a result, the time required to evaporate the excess refrigerant liquid accumulated in the lower portion of the accumulator is further shortened, and the pressure drop in the low pressure line of the refrigerant circuit can be suppressed even more quickly.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is an explanatory view showing the basic principle of the air conditioner of this embodiment, and FIG. 2 is a graph showing the relationship between the enthalpy and the pressure of the air conditioner of this embodiment during heating.

The air conditioner 10 shown in FIG.
A condenser (first heat exchanger) 12, which serves as an indoor heat exchanger during heating and serves as an outdoor heat exchanger during cooling, a throttle mechanism 13, a supercooling heat exchange section 14, and an expansion valve 15. An evaporator (second heat exchanger) 16 that serves as an outdoor heat exchanger during heating and serves as an indoor heat exchanger during cooling, and an accumulator 17
And a high temperature gas bypass circuit 19 having a bypass valve 20.

The compressor 11 compresses the low temperature low pressure gas to generate a high temperature high pressure gas.

The condenser 12 radiates heat of the high-temperature high-pressure gas compressed by the compressor 11 to condense it to generate a high-temperature high-pressure liquid. The throttling mechanism 13 converts the high-temperature high-pressure liquid generated in the condenser 12 during heating into a high-temperature high-pressure gas-liquid two-phase. The subcooling heat exchange section 14 generates the high-temperature high-pressure liquid again by radiating and condensing the high-temperature high-pressure gas-liquid two phases converted by the throttling mechanism 13 during heating, and at the same time, the high temperature generated by the condenser 12 during cooling. The high-pressure liquid is generated again by radiating heat and condensing the high-pressure liquid. The expansion valve 15 expands a high temperature high pressure liquid to generate a low temperature low pressure liquid or a gas-liquid two phase. Evaporator 1
Reference numeral 6 is for generating a low temperature low pressure gas by absorbing and evaporating the low temperature low pressure liquid or the gas-liquid two phase generated by the expansion valve 15. The accumulator 17 stores the low temperature low pressure gas generated in the evaporator 16 and supplies the low temperature low pressure gas to the compressor 11. In this accumulator 17,
Since a part of the refrigerant liquid in the low-temperature low-pressure gas-liquid existing in the low-pressure line on the downstream side of the expansion valve 15 is stored immediately after the start, etc., a part of the refrigerant liquid is sucked into the compressor 11 immediately after the start, etc. Can be prevented.

The hot gas bypass circuit 19 includes a compressor 11
Of the compressor 1 connected to the discharge side of the
The high-temperature high-pressure gas compressed by 1 is stored in the accumulator 17
Is to supply to. The bypass valve 20 opens and closes the high temperature gas bypass passage 19 immediately after the air conditioner 10 is started.

Here, the basic principle of the air conditioner 10 will be briefly described with reference to FIGS. 1 and 2.

During heating, the high temperature and high pressure gas compressed by the compressor 11 is supplied to the indoor heat exchanger (condenser) 12,
While radiating heat into the room (that is, while heating the room), it is condensed into a high-temperature high-pressure liquid. This high-temperature high-pressure liquid is used for the throttling mechanism
As shown in FIG. 2, the gas passes through 3 to be supplied to the supercooling heat exchange section 14 in the form of high-temperature high-pressure gas-liquid, where it is supplied to the expansion valve 15 as high-temperature high-pressure liquid. Here, low-temperature low-pressure gas-liquid is supplied to the outdoor heat exchanger (evaporator) 16,
It is evaporated by the heat from the outside to become a low-temperature low-pressure gas and returned to the suction side of the compressor 11 via the accumulator 17.

On the other hand, during cooling, the high-temperature high-pressure gas compressed by the compressor 11 is supplied to the outdoor heat exchanger (condenser) 12 and condensed while radiating heat to the outside to become a high-temperature high-pressure liquid. This high-temperature high-pressure liquid is supplied to the subcooling heat exchange section 14,
Here, it is further cooled and supplied to the expansion valve 15 as it is as high-temperature high-pressure liquid, where it becomes low-temperature low-pressure gas-liquid supplied to the indoor heat exchanger (evaporator) 16 and evaporated by heat from the outside. It cools the room to produce low temperature low pressure gas. This low-temperature low-pressure gas is returned to the suction side of the compressor 11 via the accumulator 17.

FIG. 3 shows the present invention of a type in which the compressor 11 is driven by a gas engine, that is, GHP (gas heat pump).
It is a block diagram of the example applied to.

The GHP1 shown in FIG. 3 is the refrigerant circuit 1 described above.
8, an oil circuit 30, an engine exhaust heat circuit 40, and the above-mentioned high temperature gas bypass circuit 19 which is the gist of the present invention. The refrigerant circuit 18 includes a compressor 11, an oil separator 21, a four-way switching valve 22, an indoor heat exchanger 12, a throttle mechanism 13, a supercooling heat exchange unit 14, an expansion valve 15, and an outdoor heat exchanger. Exchanger 16 and double tube heat exchanger 2
3, an oil cooler 24, an accumulator 17, and a filter 25. The oil circuit 30
Compressor 11, oil separator 21, and filter 31
, The oil cooler 24, and the first and second oil return circuits 3
2, 33 and a filter 25. The engine exhaust heat circuit 40 includes a gas engine 41, a double pipe heat exchanger 23, and a pump 42.

In the refrigerant circuit 18, the oil separator 21 is for separating the refrigerant gas component and the oil component in the high temperature and high pressure gas compressed by the compressor 11. The four-way switching valve 22 guides the high-temperature high-pressure gas compressed by the compressor 11 to the indoor heat exchanger 12 side during heating, and guides the high-temperature high-pressure gas to the outdoor heat exchanger 16 side during cooling. The double-pipe heat exchanger 23 exchanges heat between the low-temperature low-pressure gas that has passed through the outdoor heat exchanger 16 and the engine exhaust heat during heating, and thus the heating capacity can be further improved. Oil cooler 24
Is for exchanging heat between the low temperature low pressure gas on the upstream side of the accumulator 17 and the oil component passing through the oil separator 21.

The downstream side of the supercooling heat exchange section 14 is connected to the accumulator 17 via the liquid injector synvalve 26, whereby a part of the liquid phase can be returned to the accumulator 17. A sensitive cylinder 27 that detects the temperature of the refrigerant gas is disposed downstream of the oil cooler 24, and the sensitive cylinder 27 is connected to the expansion valve 15. This sensitive tube 2
The opening degree of the expansion valve 15 is adjusted by the temperature signal from 7. For example, when the temperature signal from the sensitive cylinder 27 rises, the opening degree of the expansion valve is increased.

A low pressure switch 28 is provided in the suction side line of the compressor 11 and is turned on when the pressure in the suction side line of the compressor 11 becomes a predetermined value or less. Compressor 11
A discharge temperature sensor 29 is arranged on the discharge side line of (1) to detect that the discharge gas temperature of the compressor 11 has reached a predetermined value or higher.

In the oil circuit 30, the first and second oil circuits are provided.
Capillary tubes are used for the oil return circuits 32 and 33, and one circuit 33 is provided with an oil bypass valve 34 that opens and closes depending on the room temperature (when heating) or the outside air temperature (when cooling). The oil bypass valve 34 is opened when it is necessary to return more oil than the normal oil return amount.

In the engine exhaust heat circuit 40, the gas engine 41 is driven by fuel such as city gas or LP gas, and drives the compressor 11 and the refrigerant circuit 1 as well.
It is for giving exhaust heat to the refrigerant gas in 8. still,
In the EHP, an electric motor is used instead of the gas engine 41.

The high temperature gas bypass circuit 19 is for supplying an excessively high temperature high pressure gas compressed by the compressor 11 to the low pressure line connecting the expansion valve 15 and the suction side of the compressor 11. Also, this high temperature gas bypass circuit 1
Reference numeral 9 is for suppressing a temporary pressure drop in the low pressure line due to a shortage of the refrigerant gas when the air conditioner 1 is started. The high temperature gas bypass circuit 19 is connected to the downstream side of the oil separator 21 and the lowermost part of the accumulator 17, so that it can be in thermal contact with the refrigerant liquid accumulated in the lower part of the accumulator 17 at the time of starting.

As shown in FIG. 4, the exposed portion 19a of the high temperature gas bypass circuit 19 to the inside of the accumulator 17 has an annular shape, whereby the contact area with the refrigerant liquid accumulated in the lower portion of the accumulator 17 at the time of starting is increased. Secured.
The exposed portion 19a is fixed to the accumulator 17 by the supporter 17a, and the exposed portion 19a is formed with a large number of holes 19b. These holes 19b are for dispersing the high-temperature high-pressure gas in the refrigerant liquid in the accumulator 17.

The bypass valve 20 opens and closes the high temperature gas bypass circuit 19 and is opened for a predetermined time (for example, several minutes) after the air conditioner 1 is started. Here, the bypass valve 20
In addition to the method of opening and closing according to time, the bypass valve 20 is electrically connected to the low pressure switch 28 to
A method of opening the bypass valve 20 when is on,
A method of closing the bypass valve 20 when the discharge temperature sensor 29 is in the on state can be considered. In the method of opening and closing the bypass valve 20 using the low pressure switch 28, when the pressure on the suction side of the compressor 11 exceeds a predetermined value, the bypass valve 2
Since 0 can be closed, an increase in the discharge temperature of the compressor 11 can be suppressed as compared with the method of opening and closing the bypass valve 20 depending on time. Further, in the method of opening and closing the bypass valve 20 using the discharge temperature sensor 29, the discharge temperature sensor 29
Since the bypass valve 20 is closed when the discharge gas temperature of the compressor 11 detected by
Compared with the method of opening and closing the bypass valve 20 depending on time,
It is possible to suppress an increase in the discharge temperature of the compressor 11.

In this embodiment, the high temperature gas bypass circuit 1 is used.
Although 9 is connected to the lowermost part of the accumulator 17, it is not limited to this and may be connected to any part of the accumulator 17.

The operation of the hot gas bypass circuit 19 of this embodiment will be described below.

Since the inside of the refrigerant circuit 18 is not warmed when the air conditioner 1 is not started, a part of the low temperature low pressure gas in the low pressure line of the refrigerant circuit 18 is liquefied to become a low temperature low pressure liquid. When the air conditioner 1 is started in this state, the low-temperature low-pressure liquid flows into the accumulator 17 and the accumulator 1
7 is stored at the bottom. At this time, the low-temperature low-pressure gas accumulated in the accumulator 17 before starting is also liquefied and the low-temperature low-pressure liquid is accumulated inside.

Therefore, the low-temperature low-pressure gas in the low-pressure line is insufficient and the pressure in the low-pressure line drops.

Since the bypass valve 20 is opened at the same time as the start-up, a part of the high temperature and high pressure gas compressed by the compressor 11 passes through the high temperature gas bypass circuit 19 connected to the lowermost part of the accumulator 17 and is exposed to the exposing portion 19a. Due to the large number of holes 19b formed in the lower part, it is dispersed in the low temperature low pressure liquid stored in the lower part of the accumulator 17. As a result, the low-temperature low-pressure liquid stored in the lower part of the accumulator 17 is rapidly evaporated.
As a result, the time required to evaporate the low-temperature low-pressure liquid accumulated in the lower portion of the accumulator is significantly shortened as compared with the case where the high-temperature gas bypass circuit 19 is connected to the low-pressure side pipe as in the conventional technique, and the low-pressure line of the refrigerant circuit 18 is reduced. The pressure drop can be suppressed faster. The high temperature gas bypass circuit 1
While the high-temperature high-pressure gas that has passed through 9 is in thermal contact with the refrigerant liquid accumulated in the lower portion of the accumulator 17, the energy of the high-temperature high-pressure gas is used to evaporate the refrigerant liquid, so that the discharge gas temperature of the compressor 11 Does not rise abnormally.

As described above, in this embodiment, since the high temperature gas bypass circuit 19 is connected to the accumulator 17, the time required to evaporate the excess refrigerant liquid accumulated in the lower portion of the accumulator 17 is different from that of the conventional technique. Compared with this, the pressure can be remarkably shortened, and the pressure drop in the low-pressure line of the refrigerant circuit 18 from the expansion valve 15 to the suction side of the compressor 11 can be suppressed faster. As a result, the durability of the compressor 11 can be improved.

Further, the high-temperature high-pressure gas supplied to the accumulator 17 via the high-temperature gas bypass circuit 19 is dispersed in the accumulator 17 having a volume larger than that of the pipe, and the flow velocity is reduced, which causes abnormal noise. Can be suppressed.

Further, since the high temperature gas bypass circuit 19 can make thermal contact with the refrigerant liquid accumulated in the accumulator 17, the time required to evaporate the excessive refrigerant liquid accumulated in the lower part of the accumulator 17 can be further shortened, and the refrigerant Circuit 1
The lowering of the pressure of the low pressure line 8 can be suppressed more quickly. This makes it possible to further improve the durability of the compressor 11. Here, while the high-temperature high-pressure gas passing through the high-temperature gas bypass circuit 19 is in thermal contact with the refrigerant liquid accumulated in the lower part of the accumulator 17, the energy of the high-temperature high-pressure gas is used to evaporate the refrigerant liquid, Compressor 1
The rise of the discharge gas temperature of No. 1 can also be suppressed.

Further, since the high temperature gas bypass circuit 19 can make thermal contact with the refrigerant liquid accumulated in the accumulator 17, the high temperature high pressure gas supplied to the accumulator 17 via the high temperature gas bypass circuit 19 accumulates in the lower part of the accumulator 17. Moreover, the flow velocity of the high-temperature high-pressure gas is further reduced by colliding with the excess refrigerant liquid, whereby the generation of abnormal noise can be reliably prevented.

Further, since the exposed portion 19a of the hot gas bypass circuit 19 into the accumulator 17 has an annular shape, the hot gas bypass circuit 19 and the accumulator 17 are provided.
The contact area with the refrigerant liquid accumulated in the lower portion increases, and the time required to evaporate the excess refrigerant liquid accumulated in the lower portion of the accumulator 17 can be further shortened, and the pressure in the low pressure line of the refrigerant circuit 18 can be further reduced. It can be suppressed quickly. This makes it possible to further improve the durability of the compressor 11.

Since a large number of holes are formed in the exposed portion 19a having an annular shape, the high-temperature high-pressure gas is dispersed more quickly in the refrigerant liquid accumulated in the accumulator 17, and as a result, accumulated in the accumulator 17. Makes the evaporation of the refrigerant liquid even more active. Therefore, the time required to evaporate the excess refrigerant liquid accumulated in the lower portion of the accumulator 17 can be further shortened, and the pressure drop in the low pressure line of the refrigerant circuit 18 can be suppressed even earlier. This makes it possible to further improve the durability of the compressor 11.

Furthermore, since the bypass valve 20 is opened and closed depending on time, special sensors, switches, etc. are not required,
It leads to cost reduction.

[0052]

The invention of claim 1 has the following effects.

Since the high temperature gas bypass circuit is connected to the accumulator, the time required to evaporate the excess refrigerant liquid accumulated in the lower part of the accumulator can be remarkably shortened as compared with the prior art, and the expansion valve is connected to the suction side of the compressor. The pressure drop in the low-pressure line of the refrigerant circuit can be suppressed more quickly.
This makes it possible to improve the durability of the compressor.

Further, the high-temperature high-pressure gas supplied to the accumulator via the high-temperature gas bypass circuit is dispersed in the accumulator and its flow velocity is reduced, whereby generation of abnormal noise can be suppressed.

The invention of claim 2 has the following effects.

Since the high temperature gas bypass circuit is brought into thermal contact with the refrigerant liquid accumulated in the accumulator, the time required to evaporate the excess refrigerant liquid accumulated in the lower part of the accumulator can be further shortened, and the pressure of the low pressure line of the refrigerant circuit can be reduced. Can be suppressed more quickly. This makes it possible to further improve the durability of the compressor. Here, while the high temperature high pressure gas passing through the high temperature gas bypass circuit is in thermal contact with the refrigerant liquid accumulated in the lower part of the accumulator, the energy of the high temperature high pressure gas is used to evaporate the refrigerant liquid. It is also possible to suppress an increase in the temperature of the discharge gas.

Further, since the high temperature gas bypass circuit is brought into thermal contact with the refrigerant liquid accumulated in the accumulator, the high temperature high pressure gas supplied to the accumulator through the high temperature gas bypass circuit becomes excessive refrigerant liquid accumulated in the lower part of the accumulator. The flow velocity of the high-temperature high-pressure gas is further reduced due to the collision, so that the generation of abnormal noise can be reliably prevented.

The invention of claim 3 has the following effects.

Since the exposed portion of the high temperature gas bypass circuit to the inside of the accumulator has an annular shape, the contact area between the high temperature gas bypass circuit and the inside of the accumulator increases, and the excess refrigerant liquid accumulated in the accumulator is further evaporated. Make it live. In this configuration, when the high temperature gas bypass circuit is brought into thermal contact with the refrigerant liquid in the accumulator as in the second aspect of the present invention, the contact area between the high temperature gas bypass circuit and the refrigerant liquid accumulated in the lower part of the accumulator is increased and the lower part of the accumulator is increased. It is possible to further reduce the time required to evaporate the excess refrigerant liquid accumulated in the refrigerant circuit, and it is possible to suppress the pressure drop in the low pressure line of the refrigerant circuit even more quickly. This makes it possible to further improve the durability of the compressor.

[Brief description of drawings]

FIG. 1 is a basic principle diagram of an air conditioner according to this embodiment.

FIG. 2 is a graph showing a relationship between enthalpy and pressure during heating of the air conditioner according to the present embodiment.

FIG. 3 is a specific configuration diagram of the air conditioner according to the present embodiment.

FIG. 4 is a perspective view of an exposed portion of the high temperature gas bypass circuit according to the present embodiment, which is exposed to the inside of the accumulator.

[Explanation of symbols]

1,10 Air Conditioner 11 Compressor 12 Indoor Heat Exchanger 15 Expansion Valve 16 Outdoor Heat Exchanger 17 Accumulator 18 Refrigerant Circuit 19 Hot Gas Bypass Circuit 19a Exposed Area of Hot Gas Bypass Circuit to Accumulator

Claims (3)

[Claims] 1. A compressor for compressing low-temperature low-pressure gas to generate high-temperature high-pressure gas, and first heat for generating high-temperature high-pressure liquid by radiating and condensing the high-temperature high-pressure gas compressed by the compressor. An exchanger, an expansion valve that expands the high-temperature high-pressure liquid generated by the first heat exchanger to generate a low-temperature low-pressure liquid, and a low-temperature low-pressure liquid generated by the expansion valve that absorbs heat and evaporates A second heat exchanger that generates a low-temperature low-pressure gas, an accumulator that stores the low-temperature low-pressure gas generated by the second heat exchanger and supplies the low-temperature low-pressure gas to the compressor, and a high-temperature high-pressure gas compressed by the compressor And a high temperature gas bypass circuit for supplying air to the accumulator. 2. The air conditioner according to claim 1, wherein the high-temperature gas bypass circuit is capable of being in thermal contact with the refrigerant liquid accumulated in the accumulator. 3. The air conditioner according to claim 1, wherein the exposed portion of the high temperature gas bypass circuit exposed in the accumulator has an annular shape.