JPH09318199A - Distributor for air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a harsh passage sound of 'vigorous noise' generated at the time of starting with a simple structure. SOLUTION: The distributor for an air conditioner comprises a flow inlet 13a as a refrigerant inlet at the time of cooling in a refrigerating cycle having a compressor of a fixed frequency, a throttle 13b for throttling the flow rate of the refrigerant fed from the inlet 13a, a collision wall 12c for colliding the refrigerant flow throttled by the throttle 13b, and a plurality of pipes for distributing the refrigerant collided at the wall 12c into a plurality of refrigerant channels of an indoor heat exchanger. The opening area S of the throttle 13b is formed at least 10mm<2> per 2.5kW of the refrigerant capacity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flow divider installed in a so-called normal type air conditioner in which the compressor is not driven by an inverter but has a constant operating frequency.

[0002]

2. Description of the Related Art Conventionally, in this type of air conditioner, since the refrigerant flow path of the indoor heat exchanger has one pass, it is not necessary to divert the refrigerant flow to flow into the indoor heat exchanger.

However, since the indoor heat exchanger has been progressing toward a reduction in diameter in recent years, a multipass technique has been developed to reduce the pressure loss.

Further, there has been conventionally proposed a flow divider which divides a refrigerant flow into each path of the multi-pass indoor heat exchanger. As an example of the flow divider, there is a flow divider in which the flow rate of the inflowing refrigerant is reduced by a throttle opening to increase the flow velocity and then collide with a collision wall to make the flow dividing balance uniform and then divide the flow into a plurality of passes.

[0005]

However, when such a conventional shunt is used in a so-called normal type air conditioner in which the compressor is not driven by an inverter but the operating frequency is constant, when the cooling operation is started, There is a problem that a large amount of annoying noise such as “shear” is generated as if a jet plane were flying.

That is, in the normal model, since the compressor is immediately operated at the maximum rotation speed at the time of startup, a large amount of refrigerant is discharged from the compressor, and about 10 times after the startup of the compressor.
Since the refrigeration cycle is not yet stable for about a second, the refrigerant discharged from the compressor is hardly liquefied in the outdoor heat exchanger and the pressure reducer, and is flowed into the flow divider in a gas state.

For this reason, when the gaseous refrigerant passes through the restrictor portion of the flow divider, an unpleasant passing sound such as "shear" is generated, and moreover, the refrigerant flow rate is large.
There is a problem that the noise is large.

Therefore, the present invention has been made in view of the above circumstances, and its purpose is to divide a jarring noise of "shear" at the time of start-up by a simple structure in an air conditioner shunt. To provide.

[0009]

According to a first aspect of the present invention, an inlet serving as a refrigerant inlet during a cooling operation of a refrigeration cycle having a compressor having a fixed operating frequency, and a flow rate of the refrigerant introduced from the inlet. And a collision wall that collides the refrigerant flow that is throttled by the restriction port, and a plurality of pipes that divide the refrigerant that is collided by the collision wall into the plurality of refrigerant flow paths of the indoor heat exchanger. And the opening area of the throttle opening is formed to be 10 mm ² or more per cooling capacity of 2.5 kW.

According to the present invention, since the opening area of the throttle opening of the flow diverter is enlarged in accordance with the cooling capacity, a large amount of gaseous refrigerant flows through the throttle opening of the flow diver when starting the cooling operation. It is possible to reduce the flow path resistance when passing and to reduce annoying passing sound.

The invention of claim 2 is characterized in that the inner diameter of at least one pipe is different from that of the other.

The invention of claim 3 is characterized in that at least one of the pipes has a wall thickness different from that of the other pipes so that the inner diameter thereof is different from that of the other pipes.

The invention according to claim 4 is characterized in that at least a part of at least one pipe is replaced with a capillary tube.

In each of these claims, the wall thickness of at least one of the plurality of pipes connected to the outlet side which is the refrigerant outlet during the cooling operation of the flow divider is changed, or at least one of the pipes is changed. By replacing the portion with a capillary tube, the inner diameter of at least a part of these pipes can be made different from the other. This makes it possible to appropriately adjust the flow rates of the refrigerant divided into the plurality of paths of the indoor heat exchanger, and easily balance the paths. That is, by simply changing the pipe to be connected to the outlet side of the flow distributor, the flow distribution balance of the refrigerant can be adjusted easily and at low cost.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS. 1 to 5, the same or corresponding parts are designated by the same reference numerals.

FIG. 1 is an exploded front view showing a part of a flow distributor 1 according to a first embodiment of the present invention in a longitudinal section, and FIG. 2 is a refrigeration cycle diagram of an air conditioner 2 in which the flow distributor 1 is incorporated. is there.

As shown in FIG. 2, the air conditioner 2 includes a so-called normal type compressor 3 having a constant operating frequency, a four-way valve 4, an outdoor heat exchanger 6 with an outdoor fan 5, an expansion valve 7, and a strainer 8. The flow divider 1 and the multi-pass indoor heat exchanger 10 with the indoor fan 9 are sequentially connected in this order by the refrigerant pipe 11 to form a closed refrigeration cycle for circulating the refrigerant.

In the refrigeration cycle, when the refrigerant is circulated in the direction of the solid line arrow in the figure by the switching operation of the four-way valve 4, the cooling operation is performed, and when it is circulated in the direction of the broken line arrow in the figure, the heating operation is performed.

Then, as shown in FIG. 1 to FIG.
Has an outer tubular portion 12 and an inner tubular portion 13 that is concentrically fitted and fixed in the small-diameter end portion 12a of the outer tubular portion 12, and the refrigerant flows in the direction of arrow A during the cooling operation and B during the heating operation. Flow in the direction of the arrow.

As shown in FIG. 1, in the outer cylinder portion 12, the central inner wall 12c at the end of the large-diameter end portion 12b is formed as a collision wall against which the refrigerant flow collides, and as shown in FIG. 12
Around c, for example, three communication holes 14a, 14b, 14c
Are drilled at equally divided positions in the circumferential direction. The three inlet pipes 15a, 15 are provided in each of the communication holes 14a-14c.
One ends of b and 15c are respectively inserted and fixed. As shown in FIG. 4, the respective tip portions of the pipes 15a to 15c are fixed to one end portions of, for example, three paths of the indoor heat exchanger 10.

On the other hand, as shown in FIG. 1, the inner cylinder portion 13 serves as an inlet 13a for the refrigerant during the cooling operation, and an opening for fitting and fixing the tip portion of the strainer 8 and a flow rate of the refrigerant flowing from the inlet 13a. Throttle opening 1 that squeezes to increase the flow velocity
And 3b are integrally formed.

The opening area S of the throttle opening 13b is formed to be 10 mm ² or more per cooling capacity of 2.5 kW. Therefore, if the cooling capacity is 5.0 kW, the throttle opening 13
The opening area S of b is formed to be 20 mm ² or more.

Further, as shown in FIG. 5, at least one of the three inlet pipes 15a to 15c, for example, the tip portion of 15a is cut off, and the cut ends are provided with other inlet pipes 15b, 1c.
The different diameter pipe 16 different from the inner diameter of 5c may be fixed concentrically and airtightly by brazing or the like, and may be inserted and fixed in the communication hole 14a of the flow distributor 1.

The different diameter pipe 16 has a wall thickness different from that of the other inlet pipe 1.
The inner diameter may be different by changing from 5a to 15c, or a capillary tube may be used. According to this, the flow rate of the refrigerant divided into the different diameter pipe 16 or the capillary tube and the other inlet pipes 15b and 15c can be appropriately adjusted easily and at low cost.

Since this embodiment is configured as described above, when the cooling operation is started, the normal type compressor 3 is immediately operated at the maximum rotation speed, and a large amount of refrigerant is discharged.

Moreover, since the refrigeration cycle 2 is still unstable at the time of startup, the refrigerant discharged from the compressor 3 is hardly liquefied by the outdoor heat exchanger 6 and the expansion valve 7, and the flow divider 1 in the gas state. The gas flows in from the inflow port 13a and is throttled by the throttle port 13b to accelerate the flow velocity.

When the gaseous refrigerant passes through the throttle opening 13b and collides with the collision wall 12c, a passing sound is generated. The opening area S of the throttle opening 13b is the cooling capacity, that is, the refrigerant flow rate. Since it is enlarged accordingly, the aperture part 13
The passage resistance of b can be reduced to reduce the passing sound.

FIG. 6 shows a curve C representing the correlation between the OA difference indicating noise and the opening area S of the throttle opening 13b when the cooling capacity is 2.5 kW, and the opening area of the throttle opening 13b is shown. It is shown that when S is 10 mm ² or more, the OA difference decreases.

Here, the OA difference means the noise level of the "shear" sound, which is the passing noise of the refrigerant in the flow diverter 1, as shown in FIG. And the noise level O at the time of start-up are shown. If this OA difference is large, the noise at the time of start-up becomes larger than that at the time of steady state, which is annoying.

FIG. 8 shows the OA when the cooling capacity is 5.0 kW.
A curve D showing the correlation between the difference and the opening area S of the aperture section 13b is shown. When the opening area S is 20 mm ² or more, the OA difference is sharply reduced to about 1.5 dB. There is.

In the above embodiment, the case where the present invention is applied to the air conditioner capable of freely heating and cooling is explained, but the present invention can also be applied to a cooling only machine.

[0032]

As described above, according to the invention of claim 1 of the present application, since the opening area of the throttle opening of the flow diverter is expanded according to the cooling capacity, a large amount of gaseous refrigerant is started at the time of starting the cooling operation. However, it is possible to reduce the flow path resistance when passing through the throttle opening portion of this shunt, and to reduce annoying passing sound.

According to the present invention, the wall thickness of at least one of the plurality of pipes connected to the outlet side, which serves as the refrigerant outlet during the cooling operation of the flow divider, can be changed, or By replacing at least a part of the pipes with a capillary tube, the inner diameter of at least a part of these pipes can be made different from the other. This makes it possible to appropriately adjust the flow rates of the refrigerant divided into the plurality of paths of the indoor heat exchanger, and easily balance the paths. That is, by simply changing the pipe to be connected to the outlet side of the flow distributor, the flow distribution balance of the refrigerant can be adjusted easily and at low cost.

[Brief description of drawings]

FIG. 1 is an exploded front view showing a part of a flow distributor according to a first embodiment of the present invention in a vertical section.

FIG. 2 is a refrigeration cycle diagram of an air conditioner incorporating the flow divider shown in FIG.

FIG. 3 is a left side view of FIG.

4 is a front view mainly showing an inlet pipe connected to the flow divider shown in FIG. 1. FIG.

5 is a right side view of FIG. 4 with a part thereof cut away.

6] The cooling capacity of the air conditioner shown in FIG. 2 is 2.5 kW
7 is a graph showing the correlation between the opening area of the aperture and the OA difference in the case of.

FIG. 7 is a graph for explaining the OA difference shown in FIG. 6 and the like.

8] The cooling capacity of the air conditioner shown in FIG. 2 is 5.0 kW
6 is a graph showing the correlation between the opening area of the flow divider and the OA difference in the case of FIG.

[Explanation of symbols]

 1 Flow Divider 2 Air Conditioner 3 Compressor (Normal Model) 4 Four-way Valve 6 Outdoor Heat Exchanger 10 Indoor Heat Exchanger 12 Outer Cylinder 12c Collision Wall 13 Inner Cylinder 13a Inlet 13b Throttle 15a, 15b, 15c Inlet pipe 16 Different diameter pipe

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tsutomu Tamagawa 336 Tatehara, Fuji City, Shizuoka Prefecture Toshiba Corporation Fuji Factory (72) Inventor Tadashi Tanaka 3-3-9 Shimbashi, Minato-ku, Tokyo Toshiba Abu・ In E Co., Ltd.

Claims (4)

[Claims] 1. An inflow port that serves as a refrigerant inflow port during a cooling operation of a refrigeration cycle having a compressor having a fixed operating frequency, a throttle port section that throttles the flow rate of the refrigerant that has flowed in from this inlet port, and this throttle port section. And a plurality of pipes for dividing the refrigerant collided by the collision wall into a plurality of refrigerant flow paths of the indoor heat exchanger, Opening area is 1 per 2.5kW cooling capacity
A shunt for an air conditioner characterized by being formed to 0 mm ² or more. 2. The flow divider for an air conditioner according to claim 1, wherein the inner diameter of at least one pipe is different from that of the other pipes. 3. The shunt of the air conditioner according to claim 1, wherein at least one of the pipes has a wall thickness different from that of the other pipes so that the inner diameter thereof is different from the other. 4. A flow divider for an air conditioner according to claim 1, wherein at least a part of at least one pipe is replaced with a capillary tube.