CN102022862B - Air conditioner - Google Patents

Abstract

The present invention relates to air conditioners. It is an object of the present invention to provide an air conditioner that improves the distribution of wind speed and achieves both energy saving and quietness. The air conditioner of the present invention comprises: a frame body having an air suction port and an air blowing port; a blower fan provided in the frame body; Roughly inverted V shape surrounding the blower fan; the indoor heat exchanger has a front side indoor heat exchanger and a rear side indoor heat exchanger, and the front side indoor heat exchanger has two straight parts and two ends connected to the two straight parts In the curved portion, the arrangement interval of the heat transfer tubes in the curved portion is smaller than the arrangement interval of the heat transfer tubes in the straight portion.

Description

air conditioner

technical field

The present invention relates to an air conditioner provided with an indoor heat exchanger.

Background technique

As a conventional air conditioner, there is an air conditioner equipped with an indoor heat exchanger composed of a front heat exchanger and a rear heat exchanger (for example, refer to Patent Document 1—Japanese Patent Laid-Open No. 2006-250366 (FIG. 1 ,image 3)). The front side heat exchanger described in Patent Document 1 has a structure composed of three straight portions and two curved portions, and curved toward the fan.

The basic characteristics of the airflow passing through such a heat exchanger having a curved portion will be described with reference to FIG. 7 . FIG. 7 shows the flow of air when resistance bodies 37 having the same internal air resistance are placed in the same air flow. As shown in FIG. 7 , the resistance body has two straight parts and a curved part whose both ends are connected to the two straight parts. The thick arrows in FIG. 7 indicate air streamlines, and the group of thin arrows 39 indicates the flow velocity distribution of the air flow downstream of the resistance body.

The air flowing from the left flows to the right through the resistance body 37 . Generally, air has the property of taking the shortest path from a place of high pressure to a place of low pressure. Therefore, at the upper part of the resistance body 37 of the shape towards the upper right, the air flow to the right in the upper reaches of the resistance body 37 becomes a flow to the right down in the resistance body 37, and after the air flow passes through the resistance body 37, it is still directed toward downstream, thus becoming the original rightward flow. Similarly, towards the bottom of the resistance body 37 of the lower right shape, the air flow upstream of the resistance body 37 to the right becomes the upper right flow in the resistance body 37. After the air flow passes through the resistance body 37, it is still directed downstream, thus becoming the original rightward flow.

In this way, at the upper and lower parts of the resistance body 37, since the direction of the flow is changed, the central part 38 of the resistance body 37 forms a constricted flow concentrating the flow, and the flow is accelerated. That is, the distribution of the wind speed passing through the resistance body 37 becomes non-uniform. When the same phenomenon occurs in the heat exchanger, the exchange heat may be reduced due to the uneven wind speed distribution, or the uneven wind speed distribution acts on the fan on the downstream side to increase the noise.

Contents of the invention

It is an object of the present invention to provide an air conditioner that improves the distribution of wind speed and achieves both energy saving and quietness.

In order to achieve the above object, the air conditioner of the present invention has: a frame with an air inlet and an air outlet; a blower fan installed in the frame; The heat transfer tube has a front-side indoor heat exchanger and a rear-side indoor heat exchanger, and the front-side indoor heat exchanger and the rear-side indoor heat exchanger are arranged in a substantially inverted V shape to surround the blower fan; It is characterized in that,

The front side indoor heat exchanger has two straight parts and a curved part with both ends connected to the two straight parts, and the indoor heat exchanger is a cross-fin-tube type indoor heat exchanger composed of a plurality of heat transfer tubes. A plurality of the heat transfer tubes are U-shaped heat transfer tubes, the bending radii of the U-shaped heat transfer tubes are all the same, and the adjacent U-shaped heat transfer tubes of the curved portion The arrangement interval is smaller than the arrangement interval of the heat transfer tubes bent in a U-shape adjacent to the straight portion, and the arrangement interval of the heat transfer tubes in the uppermost column of the curved portion is smaller than the arrangement interval of the heat transfer tubes in the straight portion. Small, the number of columns of the heat transfer tubes along the flow direction of the air in the front side indoor heat exchanger is the same.

The effects of the present invention are as follows.

According to the present invention, it is possible to provide an air conditioner that improves the wind speed distribution and achieves both improved energy saving and quietness.

Description of drawings

FIG. 1 is a diagram showing the arrangement of heat transfer tubes of a front-side indoor heat exchanger.

Fig. 2 is a diagram showing the structure of a refrigeration cycle.

Fig. 3 is a diagram showing the structure of a cross-fin-tube heat exchanger.

Fig. 4 is a diagram showing a cross section of an indoor unit.

Fig. 5 is a diagram showing the shape of a front-side indoor heat exchanger.

Fig. 6 is a diagram showing the arrangement of heat transfer tubes of the front-side indoor heat exchanger.

Fig. 7 is a diagram showing an air flow passing through a resistance body having a bent portion.

In the picture:

1—outdoor unit, 2—compressor, 3—four-way valve, 4—outdoor heat exchanger, 5—propeller blower, 6—throttling device, 7—indoor unit, 8—indoor heat exchanger, 9—direct current Fan, 10—connecting piping, 11—radiating fin, 12—heat transfer pipe, 13—joint parts, 14—rear side frame of indoor unit, 15—front side frame of indoor unit, 16—front panel of indoor unit, 17— Air direction control panel, 18—front frame of the upper part of the indoor unit, 19—coarse filter frame, 20—indoor heat exchanger on the front side, 21—indoor heat exchanger on the back side, 22—air suction port on the front, 23—air on the upper side Suction port, 24—air outlet, 25, 26, 27—straight portion on the leading edge side, 28, 29—curved portion on the leading edge side, 30, 31, 32—straight portion on the trailing edge side, 33, 34—straight edge portion on the trailing edge side Curved part, 35, 36—curved part of heat exchanger, 37—resistance body, 38—central part of resistance body, 39—thin arrow group, 40—heat transfer tube with small bending radius of U-shaped part, 50, 51, 52—the straight line part of the heat exchanger.

Detailed ways

Embodiments of the present invention will be described below using the drawings.

Example 1

A first embodiment of the present invention will be described with reference to FIGS. 1 to 5 and 7 . First, the basic structure of the air conditioner of the present embodiment will be described. Fig. 2 is a structural diagram of a refrigeration cycle. The air conditioner of this embodiment realizes its function by connecting the outdoor unit 1 and the indoor unit 7 through the connecting pipe 10 . The outdoor unit 1 includes a compressor 2 , a four-way valve 3 , an outdoor heat exchanger 4 , a throttling device 6 , and a propeller blower 5 . The indoor unit 7 includes an indoor heat exchanger 8 and a blower fan. Furthermore, a DC fan 9 can be used as the blower fan.

Next, first, the function of each component during air-cooling operation will be described. The high-pressure gaseous refrigerant compressed by the compressor 2 is condensed by releasing heat to the outside air by the outdoor heat exchanger 4 to become a high-pressure liquid refrigerant. The liquid refrigerant is decompressed by the action of the expansion device 6 , becomes a low-temperature and low-pressure gas-liquid two-phase state, and flows to the indoor unit 7 through the connecting pipe 10 . The refrigerant entering the indoor unit 7 absorbs heat from the indoor air in the indoor heat exchanger 8 to evaporate. The refrigerant evaporated from the indoor unit returns to the outdoor unit 1 through the connecting pipe 10 and is compressed by the compressor 2 again through the four-way valve 3 .

During heating operation, the four-way valve 3 switches the refrigerant flow path, and the high-pressure gaseous refrigerant compressed by the compressor 2 flows to the indoor unit 7 through the four-way valve 3 and the connecting pipe 10 . The refrigerant entering the indoor unit 7 is condensed by dissipating heat to the indoor air in the indoor heat exchanger 8 to become a high-pressure liquid refrigerant. This liquid refrigerant flows into the outdoor unit 1 through the connecting pipe 10 . The liquid refrigerant entering the outdoor unit 1 is decompressed by the throttling device 6 and becomes a gas-liquid two-phase state at low temperature and low pressure. The refrigerant in a low-temperature and low-pressure gas-liquid two-phase state flows into the outdoor heat exchanger 4, absorbs heat from the outdoor air, evaporates, and becomes a gaseous refrigerant. This gaseous refrigerant is compressed again by the compressor 2 through the four-way valve 3 .

FIG. 3 shows the structure of a cross-fin-tube heat exchanger. This heat exchanger is formed by penetrating a plurality of aluminum fins 11 through copper heat transfer tubes 12 bent in a U-shape. The heat transfer tubes 12 inserted into the fins are expanded by hydraulic pressure or mechanical means, so that the fins 11 and the heat transfer tubes 12 are in close contact with each other. Further, joint fittings 13 are welded to the ends of the heat transfer tubes 12 to form refrigerant flow paths.

Fig. 4 is a sectional view of the indoor unit of the air conditioner (section perpendicular to the axis of the heat transfer tube). The top of the frame is provided with an air suction port (specifically, a front air suction port 22 is provided on the front of the frame body, and an upper air suction port 23 is provided above the frame body), and an air suction port is provided below the frame body. Blow outlet 24. A DC fan 9 is arranged in the frame, and a cross-fin-tube heat exchanger is arranged on the way from the air inlet to the air duct of the DC fan. The indoor heat exchanger 8 is composed of a front-side indoor heat exchanger 20 and a rear-side indoor heat exchanger 21 . Furthermore, the front-side indoor heat exchanger 20 and the rear-side indoor heat exchanger 21 are arranged in a substantially inverted V shape so as to surround the DC fan 9 . When the DC fan 9 is started, the indoor air flows in from the air inlet, uses the indoor heat exchanger 8 to exchange heat with the internal refrigerant, and is blown out from the air outlet 24, thereby air-conditioning the indoor air.

Next, the detailed cross-sectional shape of the front-side indoor heat exchanger 20 will be described with reference to FIG. 5 . At the windward leading edge portion of the front side indoor heat exchanger 20, the leading edge side straight portion 25 and the leading edge side straight portion 26 are connected by the leading edge side curved portion 28, and the leading edge side straight portion 26 and the leading edge side straight portion 27 are connected by The leading edge side curved portion 29 is connected. Moreover, at the leeward trailing edge portion of the front side indoor heat exchanger 20, the trailing edge side straight portion 30 and the trailing edge side straight portion 31 are connected by the trailing edge side curved portion 33, and the trailing edge side straight portion 31 and the trailing edge side straight portion 32 are connected by a rear edge side bent portion 34 . With this structure, the front side indoor heat exchanger is formed so as to bend toward the direction of the DC fan 9 .

The upper hatched portion in FIG. 5 indicates the heat exchanger curved portion 35 surrounded by the leading edge side curved portion 28 of the windward leading edge and the trailing edge side curved portion 33 of the leeward trailing edge. Furthermore, the hatched portion on the lower side in FIG. 5 indicates the heat exchanger curved portion 36 surrounded by the leading edge side curved portion 29 of the windward leading edge and the trailing edge side curved portion 34 of the leeward trailing edge. The portion without hatching is the heat exchanger straight portion 50 surrounded by the leading edge side straight portion 25 of the upwind leading edge and the trailing edge side straight portion 30 of the leeward trailing edge, the leading edge side straight portion 26 of the upwind leading edge and the The heat exchanger linear portion 51 surrounded by the trailing edge straight portion 31 of the leeward trailing edge, the heat exchanger straight portion 51 surrounded by the leading edge straight portion 27 of the upwind leading edge and the trailing edge straight portion 32 of the leading edge side leeward trailing edge Section 52. Here, both ends of the heat exchanger curved portion 35 are connected to the heat exchanger straight portion 50 and the heat exchanger straight portion 51 , and both ends of the heat exchanger curved portion 36 are connected to the heat exchanger straight portion 51 and the heat exchanger straight portion 51 . Section 52. As described with reference to FIG. 7 , the heat exchanger curved portions 35 and 36 are easier to accelerate the flow of air than the heat exchanger straight portions 50 , 51 , and 52 .

Next, the arrangement of the heat transfer tubes in the cross section of the front side indoor heat exchanger 20 of this embodiment will be described with reference to FIG. 1 . In the front-side indoor heat exchanger 20, three rows of heat transfer tubes are arranged along the air flow direction, and twelve layers are arranged in a direction perpendicular to the air flow direction. The dotted line in the drawing indicates the portion where the inserted heat transfer tube is bent into a U shape. Here, L0 represents the arrangement interval of the heat transfer tubes in the straight portion of the heat exchanger. L1 and L2 indicate the smallest arrangement interval of the heat transfer tubes among the arrangement intervals of the heat transfer tubes in the heat exchanger curve portion 35 and the heat exchanger curve portion 36 . In this embodiment, the relationship between L0, L1, and L2 is shown in the following formula.

L1<L0

L2<L0

That is, the arrangement intervals of the heat transfer tubes in the heat exchanger curved portions 35 and 36 where the air is easily accelerated are narrower than the arrangement intervals of the heat transfer tubes in the heat exchanger straight portions 50, 51 and 52. The ventilation resistance at 36 is relatively large, and the acceleration of the air flow at the heat exchanger curves 35 and 36 can be suppressed. That is, uneven wind velocity distribution of the air passing through the heat exchanger can be reduced, and it is possible to achieve both improvement of energy saving and noise reduction.

In order to increase the ventilation resistance of the heat exchanger curves 35 and 36, it can be realized by reducing the arrangement interval of the heat transfer tubes in any one of the first to third rows. However, when the air conditioner is running, the air becomes colder, the moisture in the air is condensed, and when condensation occurs on the fins of the heat exchanger, since the part with the highest humidity passes through the first row, it adheres more to the fins of the first row. Lots of condensation. When dew condensation water adheres to the heat sink, the ventilation resistance will increase because the portion through which air can pass decreases. That is, when reducing the arrangement interval of the tubes to increase the ventilation resistance, it is more effective to reduce the arrangement interval of the heat transfer tubes in the first row of the uppermost wind as in this embodiment.

Furthermore, in this embodiment, by making the arrangement intervals of the heat transfer tubes in the heat exchanger curved portions 35, 36 smaller than the arrangement intervals of the heat transfer tubes in the heat exchanger straight portions 50, 51, 52, it is possible to prevent the air from being easily accelerated. The acceleration of the air flow at the curved parts 35 and 36 of the heat exchanger reduces the non-uniform wind speed distribution of the air passing through the heat exchanger. However, the present invention is not only constituted by an indoor heat exchanger having a heat exchanger straight portion and a heat exchanger curved portion as in this embodiment, even in an indoor heat exchanger that does not have a heat exchanger straight portion but only consists of a heat exchanger curved portion In this case, the variation of the curvature of the curved portion of the heat exchanger creates a region where the air is likely to accelerate, which is also effective when the wind speed distribution of the air passing through the indoor heat exchanger is uneven. In this case, the arrangement interval of the heat transfer tubes in the larger curvature portion of the front side heat exchanger may be smaller than the arrangement interval of the heat transfer tubes in the smaller curvature portion of the front side heat exchanger. Since the arrangement interval of the heat transfer tubes in the part with a larger curvature of the front side heat exchanger is smaller than that in the part with a smaller curvature, the air in the part with a smaller curvature can be prevented from being easily accelerated. The acceleration of the flow can thus reduce the uneven distribution of the wind speed of the air passing through the heat exchanger.

Moreover, as explained using FIG. 3 , since the heat exchanger of the cross-fin-tube type uses U-shaped heat transfer tubes, it is necessary to make U-shaped heat transfer tubes in order to make the arrangement intervals of the heat transfer tubes different. The bending radii of the tubes are different (i.e., it is necessary to prepare a variety of heat transfer tubes.). However, in this embodiment, by reducing the arrangement interval of adjacent heat transfer tubes among the two U-shaped heat transfer tubes (that is, by adjusting the adjacent U-shaped heat transfer tubes to L0, L1, and L2), the A heat exchanger can be configured using only one type of U-shaped heat transfer tube without requiring multiple types of heat transfer tubes.

Example 2

A second embodiment of the present invention will be described using FIG. 6 . Since the basic structure of the air conditioner of this embodiment is the same as that of the first embodiment, detailed description will be omitted, and only differences will be described.

Fig. 6 shows the arrangement of the heat transfer tubes of the front-side indoor heat exchanger of this embodiment. In the front-side indoor heat exchanger of this embodiment, three rows of heat transfer tubes are arranged along the air flow direction, and twelve layers are arranged in a direction perpendicular to the air flow direction. The dotted line in the drawing indicates the portion where the inserted heat transfer tube is bent into a U shape. Here, L0 represents the arrangement interval of the heat transfer tubes in the straight portion of the heat exchanger. L1 and L2 indicate the smallest arrangement interval of the heat transfer tubes among the arrangement intervals of the heat transfer tubes in the heat exchanger curve portion 35 and the heat exchanger curve portion 36 . In the present embodiment, the relationship between L0, L1, and L2 is expressed in the following formula as in the first embodiment.

L1<L0

L2<L0

That is, since the arrangement intervals of the heat transfer tubes of the heat exchanger curve parts 35 and 36 where the air is easily accelerated are narrower than the arrangement intervals of the heat transfer tubes of the heat exchanger straight parts 50, 51 and 52, the heat exchanger curve parts 35, The ventilation resistance at 36 is relatively large, so that the acceleration of the air flow at the heat exchanger curves 35, 36 can be suppressed. That is, it is possible to reduce uneven wind speed distribution of the air passing through the heat exchanger, and it is possible to achieve both the effect of improving energy saving and achieving quietness.

In the present invention, in the first embodiment, the U-shaped portion of the heat transfer tube (the portion drawn with a dotted line in FIG. 6 ) does not exist in the portion where the heat transfer tube is arranged at a small interval. However, in this embodiment, the U-shaped portion of the heat transfer tube (the portion drawn with a dotted line in FIG. 6 ) exists in a portion where the arrangement interval of the heat transfer tube is small. That is, by using the heat transfer tubes 40 whose U-shaped portion has a smaller bending radius than other heat transfer tubes, the arrangement interval of the heat transfer tubes is reduced.

Claims (1)

1. An air conditioner comprising: A frame with an air suction port and an air blowing port; a blower fan located in the above-mentioned frame; and An indoor heat exchanger having cooling fins and heat transfer pipes passing through the cooling fins, a front indoor heat exchanger and a rear indoor heat exchanger, the front indoor heat exchanger and the rear indoor heat exchanger Configured in a roughly inverted V shape to surround the above-mentioned air supply fan; it is characterized in that, The front-side indoor heat exchanger has two straight parts and a curved part with both ends connected to the two straight parts, The above-mentioned indoor heat exchanger is an indoor heat exchanger of a cross-fin tube type composed of a plurality of the above-mentioned heat transfer tubes, the plurality of the above-mentioned heat transfer tubes are heat transfer tubes bent into a U shape, and the above-mentioned heat transfer tubes bent into a U shape The bend radii of the tubes are all the same, An arrangement interval of the heat transfer tubes bent in a U-shape adjacent to the curved portion is smaller than an arrangement interval of the heat transfer tubes bent in a U-shape adjacent to the straight portion, The arrangement interval of the heat transfer tubes in the uppermost row of the curved portion is smaller than the arrangement interval of the heat transfer tubes in the linear portion, The number of rows of the heat transfer tubes along the air flow direction in the front side indoor heat exchanger is the same.

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