WO2017158716A1

WO2017158716A1 - Throttle mechanism and air-conditioning system

Info

Publication number: WO2017158716A1
Application number: PCT/JP2016/058116
Authority: WO
Inventors: 創一朗越; 琢也向山
Original assignee: 三菱電機株式会社
Priority date: 2016-03-15
Filing date: 2016-03-15
Publication date: 2017-09-21
Also published as: JPWO2017158716A1; CN206861938U

Abstract

The throttle mechanism according to the present invention is provided with: an electronic expansion valve; a capillary tube that is disposed on the downstream side of the electronic expansion valve in the direction of refrigerant flow; and refrigerant piping that connects between the electronic expansion valve and the capillary tube, wherein the refrigerant piping is provided with a first pipe connected to the electronic expansion valve, and is also provided with a second pipe that is disposed between the first pipe and the capillary tube and has an inner diameter larger than that of the first pipe.

Description

Throttle mechanism and air conditioner

The present invention relates to a throttle mechanism that suppresses sound generated when a refrigerant flows, and an air conditioner including the throttle mechanism.

FIG. 6 is a refrigerant circuit diagram showing a conventional air conditioner. The air conditioner 200 is configured by connecting a compressor 201, an outdoor heat exchanger 202, a throttle mechanism 203, and an indoor heat exchanger 204 in series with a refrigerant pipe. Further, in the conventional air conditioner 200 shown in FIG. 6, an electronic expansion valve 205 and a capillary tube 206 (capillary tube) are connected in series along the refrigerant flow direction to constitute a throttle mechanism 203. That is, the air conditioner 200 adjusts the pressure reduction effect of the capillary tube 206 by adjusting the opening degree of the electronic expansion valve 205.

In the throttle mechanism of an air conditioner, when the pressure of the refrigerant is reduced, a sound due to the flow of the refrigerant is often generated. As described above, the electronic expansion valve 205 and the capillary tube 206 are connected in series to form the throttle mechanism 203, so that compared with the case where the throttle mechanism 203 is configured by only one of the electronic expansion valve 205 and the capillary tube 206, the refrigerant Although the sound caused by the flow can be suppressed, a loud sound may still be generated. Such a loud sound propagates to the indoor heat exchanger through the refrigerant pipe, giving the user an unpleasant feeling.

Therefore, in the conventional air conditioner in which the electronic expansion valve and the capillary tube are connected in series to form the throttle mechanism, the throttle amount of the electronic expansion valve is adjusted so that the decompression effect of the electronic expansion valve and the capillary is equally divided. The thing is proposed (for example, refer patent document 1). Thus, by adjusting the opening degree of the electronic expansion valve, the flow rate of the refrigerant at the capillary outlet is reduced, and the propagation of the sound caused by the refrigerant flow to the indoor heat exchanger is aimed at.

Japanese Patent Laid-Open No. 8-219591

In a conventional air conditioner in which an electronic expansion valve and a capillary tube are connected in series to form a throttling mechanism, the opening degree of the electronic expansion valve changes due to changes in the operating environment temperature and the compressor rotational speed. For this reason, as in Patent Document 1, it is actually very difficult to set the opening of the electronic expansion valve so that the decompression effect of the electronic expansion valve and the capillary is equally divided. In addition, since the characteristics (frequency, sound pressure level, etc.) of sound generated when the refrigerant flows in the throttle mechanism also change with the opening of the electronic expansion valve, it is difficult to suppress the generation of all sounds. . Therefore, the conventional air conditioner still has a problem that the sound generated when the refrigerant flows in the throttle mechanism propagates to the indoor heat exchanger, causing discomfort to the user.

The present invention has been made in order to solve the above-described problem, and a throttle mechanism that can suppress the sound generated when the refrigerant flows from propagating to the indoor heat exchanger more than before, and the throttle mechanism. It aims at obtaining the equipped air conditioner.

A throttling mechanism according to the present invention includes an electronic expansion valve, a capillary tube provided downstream of the electronic expansion valve in a refrigerant flow direction, and a refrigerant pipe that connects the electronic expansion valve and the capillary tube, The refrigerant pipe includes a first pipe connected to the electronic expansion valve, and a second pipe provided between the first pipe and the capillary and having an inner diameter larger than the inner diameter of the first pipe. Is.

The air conditioner according to the present invention includes the throttle mechanism according to the present invention and an indoor heat exchanger connected to the capillary of the throttle mechanism.

In the throttling mechanism according to the present invention, the sound generated when the refrigerant flows through the electronic expansion valve enters the second pipe through the first pipe in the second pipe having a larger inner diameter than the first pipe. The sound propagation energy is dispersed and the sound pressure level is lowered. Further, in the throttle mechanism according to the present invention, a rapid contraction portion is formed in which the inner diameter is rapidly reduced from the second pipe to the capillary. For this reason, in this rapid contraction part, the sound wave which can penetrate | invade into a capillary tube is limited, and the propagation energy attenuate | damps by the sound wave which could not penetrate | invade staying in the 2nd piping and canceling. Therefore, by adopting the throttle mechanism according to the present invention in the air conditioner, it is possible to suppress the propagation of sound having various characteristics generated by the electronic expansion valve to the indoor heat exchanger through the refrigerant pipe.

It is a refrigerant circuit figure which shows the air conditioner which concerns on Embodiment 1 of this invention. It is an enlarged view which shows the capillary vicinity of the aperture mechanism of the air conditioner which concerns on Embodiment 1 of this invention. It is a figure which shows the silencing effect of the aperture mechanism which concerns on Embodiment 1 of this invention. It is an enlarged view which shows the capillary vicinity of the aperture mechanism of the air conditioner which concerns on Embodiment 2 of this invention. It is a figure which shows the silencing effect of the aperture mechanism which concerns on Embodiment 2 of this invention. It is a refrigerant circuit diagram which shows the conventional air conditioner.

Embodiment 1 FIG.
FIG. 1 is a refrigerant circuit diagram illustrating an air conditioner according to Embodiment 1 of the present invention. FIG. 2 is an enlarged view showing the vicinity of the capillary of the throttle mechanism of the air conditioner. In addition, the white arrow shown in FIG.1 and FIG.2 has shown the flow direction of the refrigerant | coolant.

The air conditioner 100 according to Embodiment 1 is configured by connecting a compressor 1, an outdoor heat exchanger 2, a throttle mechanism 3, and an indoor heat exchanger 4 in series with a refrigerant pipe. The compressor 1 compresses a low-temperature and low-pressure gas refrigerant into a high-temperature and high-pressure gas refrigerant. The outdoor heat exchanger 2 is provided, for example, outdoors, and discharges heat from the high-temperature and high-pressure gas refrigerant discharged from the compressor 1 to the outside air and condenses it into a high-pressure liquid refrigerant. The throttle mechanism 3 decompresses and expands the high-pressure liquid refrigerant flowing out of the outdoor heat exchanger 2 to form a low-temperature and low-pressure gas-liquid two-phase refrigerant. The indoor heat exchanger 4 is provided in an air-conditioning target space such as a room, for example, and causes the low-temperature and low-pressure gas-liquid two-phase refrigerant that has flowed out of the throttle mechanism 3 to absorb the heat of the air in the air-conditioning target space. To evaporate.

The throttling mechanism 3 according to the first embodiment includes an electronic expansion valve 5, a capillary tube 20 (capillary tube) provided downstream of the electronic expansion valve 5 in the refrigerant flow direction, and the electronic expansion valve 5. The refrigerant | coolant piping which connects the said capillary 20 in series is provided. The capillary 20 is more specifically connected to the indoor heat exchanger 4 through the refrigerant pipe 7 at the outlet 22 of the capillary 20. Here, a throttle mechanism configured by connecting an electronic expansion valve and a capillary tube in series with a refrigerant pipe has been proposed. Specifically, as shown in FIG. 6, in such a conventional throttle mechanism 203, an electronic expansion valve 205 and a capillary tube 206 are connected in series by a refrigerant pipe 207.

On the other hand, in the throttle mechanism 3 according to the first embodiment, the second pipe 10 is provided between the first pipe 6 and the capillary 20 corresponding to the conventional refrigerant pipe 207. That is, in the first embodiment, the refrigerant pipe connecting the electronic expansion valve 5 and the capillary 20 is between the first pipe 6 connected to the electronic expansion valve 5 and the first pipe 6 and the capillary 20. The 2nd piping 10 provided in this is provided. The inner diameter of the second pipe 10 is larger than the inner diameter of the first pipe 6. In other words, since the capillary 20 is the portion having the smallest inner diameter in the flow path through which the refrigerant flows, the inner diameter of the second pipe 10 is larger than the inner diameter of the capillary 20. For this reason, the inner diameter of the flow path through which the refrigerant flows from the downstream end 11 of the second pipe 10 to the inlet end of the capillary 20 (in the first embodiment, the end on the side where the inlet 21 is formed). Constitutes an abrupt contraction part that rapidly shrinks. This rapid contraction portion can arbitrarily set the reduction ratio of the inner diameter of the flow path through which the refrigerant flows.

In the first embodiment, the downstream end 11 of the second pipe 10 and the capillary tube 20 are connected by a third pipe 23 that is shorter than the first pipe 6. However, the configuration is not limited thereto, and the downstream end 11 of the second pipe 10 and the capillary tube 20 may be directly connected. As will be described later, the rapid contraction portion formed from the downstream end portion 11 of the second pipe 10 to the capillary tube 20 is a portion that attenuates sound propagation energy. When the downstream end 11 of the second pipe 10 and the capillary tube 20 are directly connected, the degree of reduction of the inner diameter of the flow path through which the refrigerant flows can be increased, that is, the degree of arbitrary setting of the reduction ratio of the inner diameter increases. This is preferable because the attenuation effect of sound propagation energy can be improved.

In the throttle mechanism 3 according to the first embodiment configured as described above, the sound pressure level of the sound entering the second pipe 10 such as the sound generated when the refrigerant flows through the electronic expansion valve 5 is expressed as follows. Can be reduced.
Specifically, the sound entering the second pipe 10 enters from the first pipe 6 side (upper side in FIG. 2), similarly to the refrigerant. When sound enters the second pipe 10 through the first pipe 6, the sound propagation energy is dispersed in the second pipe 10 having an inner diameter larger than that of the first pipe 6, and the sound pressure level is lowered. Moreover, in the rapid contraction part comprised from the downstream edge part 11 of the 2nd piping 10 to the capillary tube 20, the sound wave which can penetrate | invade into the capillary tube 20 is limited, and the sound wave which could not penetrate | invade remains in the 2nd piping 10, and cancels out. This attenuates the propagation energy. By the above action, the sound propagation energy at the outlet 22 of the capillary 20 is reduced, and as a result, the sound pressure level transmitted from the indoor heat exchanger 4 to the user can also be lowered.

FIG. 3 is a diagram showing a silencing effect of the aperture mechanism according to Embodiment 1 of the present invention. Here, the horizontal axis of FIG. 3 indicates the frequency of sound entering the second pipe 10 of the throttle mechanism 3. Moreover, the continuous line shown in FIG. 3 has shown the silencing effect of the aperture mechanism 3 which concerns on this Embodiment 1. FIG. In addition, the broken line shown in FIG. 3 shows the silencing effect of the comparative example. In this comparative example, the second pipe 10 is removed from the throttle mechanism 3 according to the first embodiment, and the first pipe 6 and the capillary 20 are connected. In other words, it can be said that the comparative example shows the silencing effect of the conventional diaphragm mechanism 203 shown in FIG.

Also in the comparative example, the inner diameter of the flow path through which the refrigerant flows is reduced at the connection point between the first pipe 6 and the capillary 20. For this reason, as shown in FIG. 3, there is a slight silencing effect. On the other hand, as in the first embodiment, the second pipe 10 having an inner diameter larger than that of the first pipe 6 is provided on the upstream side of the capillary tube 20 to increase the reduction ratio of the inner diameter of the flow path through which the refrigerant flows, thereby increasing 350 In almost all regions above [Hz], an effect of reducing the sound pressure level is obtained as compared with the comparative example.

As described above, in the air conditioner 100 including the throttle mechanism 3 according to the first embodiment, it is possible to suppress the propagation of sound having various characteristics to the indoor heat exchanger 4.

Embodiment 2. FIG.
FIG. 4 is an enlarged view showing the vicinity of the capillary tube of the throttle mechanism of the air conditioner according to Embodiment 2 of the present invention. Hereinafter, the air conditioner 100 according to Embodiment 2 will be described with reference to FIG. In the second embodiment, items that are not particularly described are the same as those in the first embodiment, and the same functions and configurations are described using the same reference numerals.

The difference between the air conditioner 100 according to the second embodiment and the first embodiment is the configuration of the aperture mechanism 3. Specifically, in the throttle mechanism 3 according to the second embodiment, the refrigerant inlet 21 to the capillary 20 is disposed in the internal space of the second pipe 10. In the second embodiment, by inserting the end of the third pipe 23 on the second pipe 10 side into the second pipe 10, the refrigerant inlet 21 to the capillary 20 is connected to the inside of the second pipe 10. Arranged in space. Of course, the refrigerant inlet 21 to the capillary 20 may be disposed in the internal space of the second pipe 10 by inserting the end of the capillary 20 on the second pipe 10 side into the second pipe 10.

Also in the throttle mechanism 3 configured in this way, as in the first embodiment, when sound enters the second pipe 10 through the first pipe 6, the second pipe having a larger inner diameter than the first pipe 6. The propagation energy of the sound is dispersed within 10 and the sound pressure level is lowered. Moreover, in the rapid contraction part comprised from the downstream edge part 11 of the 2nd piping 10 to the capillary tube 20, the sound wave which can penetrate | invade into the capillary tube 20 is limited, and the sound wave which could not penetrate | invade remains in the 2nd piping 10, and cancels out. As a result, the propagation energy is attenuated. By the above action, the sound propagation energy at the outlet 22 of the capillary 20 is reduced, and as a result, the sound pressure level transmitted from the indoor heat exchanger 4 to the user can also be lowered.

Furthermore, in the throttling mechanism 3 according to the second embodiment, the refrigerant inlet 21 to the capillary tube 20 is disposed in the internal space of the second pipe 10, so that it is near the downstream end 11 of the second pipe 10. It is possible to suppress the energy of the sound bounced back and entering the entrance 21. That is, it is possible to further suppress the sound entering from the inlet 21 from being transmitted to the indoor heat exchanger 4 side through the capillary 20.

Further, by arranging the refrigerant inlet 21 to the capillary 20 in the internal space of the second pipe 10, the reduction rate of the inner diameter of the flow path through which the refrigerant flows can be further reduced. Specifically, in the first embodiment, an inclined portion is formed at the downstream end portion 11 of the second pipe 10 so that the inner diameter is gradually narrowed, and the inlet 21 of the capillary tube 20 is connected to the downstream end portion 11. It was. On the other hand, in Embodiment 2, the inner diameter of the flow path through which the refrigerant flows can be reduced without sandwiching the inclined portion. For this reason, the effect of attenuating the sound propagation energy by the abrupt contraction portion in which the inner diameter of the flow path through which the refrigerant flows is further increased.

FIG. 5 is a diagram showing the silencing effect of the aperture mechanism according to Embodiment 2 of the present invention. Here, the horizontal axis of FIG. 5 indicates the frequency of the sound entering the second pipe 10 of the throttle mechanism 3. Moreover, the dashed-dotted line shown in FIG. 5 has shown the silencing effect of the aperture mechanism 3 which concerns on this Embodiment 2. FIG. The silencing effect of the throttling mechanism 3 according to the second embodiment is that the refrigerant inlet 21 to the capillary 20 is arranged at a position of the second pipe 10 that is ½ of the refrigerant flow direction. In FIG. 5, the silencing effect of the diaphragm mechanism 3 shown in the first embodiment is also indicated by a solid line.

As shown in FIG. 6, it can be seen that the diaphragm mechanism 3 according to the second embodiment can obtain the effect of reducing the sound pressure level in the same manner as the diaphragm mechanism 3 described in the first embodiment. In particular, the diaphragm mechanism 3 according to the second embodiment is more effective in silencing the sound having a higher frequency than the diaphragm mechanism 3 shown in the first embodiment.

As described above, in the air conditioner 100 provided with the throttle mechanism 3 according to the second embodiment, the silencing effect can be further improved as compared with the first embodiment, and the sound with various characteristics can be obtained from the indoor heat exchanger 4. Propagation up to can be further suppressed. Further, the diaphragm mechanism 3 according to the second embodiment also has an advantage that the effect can be obtained by a small shape change (that is, a small cost fluctuation) of the component.

Here, the frequency band of the sound with a large silencing effect is determined by the distance from the inlet of the second pipe 10 to the inlet 21 of the refrigerant to the capillary 20. The throttling mechanism 3 according to the second embodiment determines the distance from the inlet of the second pipe 10 to the refrigerant inlet 21 from the inlet of the second pipe 10 depending on the insertion length of the third pipe 23 or the capillary 20 into the second pipe 10. Can be set. For this reason, the diaphragm mechanism 3 according to the second embodiment can easily change the frequency band of a sound with a large silencing effect.

In addition, it is also possible to change the inlet position of the sound entering the second pipe 10 by inserting the end of the first pipe 6 into the second pipe 10. For this reason, by inserting the end of the first pipe 6 into the second pipe 10, it is possible to easily change the frequency band of the sound having a great silencing effect. At this time, of course, the end of the third pipe 23 or the capillary 20 may be inserted into the second pipe 10.

1 compressor, 2 outdoor heat exchanger, 3 throttle mechanism, 4 indoor heat exchanger, 5 electronic expansion valve, 6 1st piping, 7 refrigerant piping, 10 2nd piping, 11 downstream end, 20 capillary tube, 21 inlet, 22 outlet, 23 3rd piping, 100 air conditioner, 200 air conditioner (conventional), 201 compressor (conventional), 202 outdoor heat exchanger (conventional), 203 throttle mechanism (conventional), 204 chambers Inner heat exchanger (conventional), 205 electronic expansion valve (conventional), 206 capillary tube (conventional), 207 refrigerant piping (conventional).

Claims

An electronic expansion valve, a capillary tube provided downstream of the electronic expansion valve in the flow direction of the refrigerant, and a refrigerant pipe connecting the electronic expansion valve and the capillary tube,
The refrigerant pipe is
A first pipe connected to the electronic expansion valve;
A second pipe provided between the first pipe and the capillary, the inner diameter of which is larger than the inner diameter of the first pipe;
A diaphragm mechanism characterized by comprising:
The throttle mechanism according to claim 1, wherein an inlet of the refrigerant to the capillary is disposed in an internal space of the second pipe.
A third pipe connecting the second pipe and the capillary;
The throttle mechanism according to claim 2, wherein an end of the third pipe on the second pipe side is inserted into the second pipe.
The throttle mechanism according to claim 2, wherein an end of the capillary tube is inserted into the second pipe.
The throttle mechanism according to any one of claims 1 to 4, wherein an end of the first pipe is inserted into the second pipe.
A diaphragm mechanism according to any one of claims 1 to 5,
An indoor heat exchanger connected to the capillary of the throttle mechanism;
An air conditioner characterized by comprising: