JPH09318285A - Heat-exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten a defrosting time, to prevent lowering of heat-exchange efficiency, and to improve heating capacity by a method wherein at least the end part on the windward of a fin for heat-exchange is formed in a wave-form shape along the sectional shape of a heat-exchange pipe. SOLUTION: A fin 1 for heat-exchange has right and left end parts 1b and 1a being not straight and is formed in a wave-form shape along the sectional shape of a heat-exchange pipe 2. Namely, some part of the heat-exchanger pipe forms a protrusion part 1c drawing a circle centering around the pipe 2 and the intermediate parts of upper and lower heat-exchange pipes 2 and 2 reversely form a recessed part 1d. As noted above, since the end part 1a and 1b of the fin 1 for heat-exchanger are formed in a wave-form shape matching with the sectional shape of the heat-exchange pipe 2, heat conduction from the heat-exchanger pipe 2 is closely spread over the fin. This constitution melts evenly frost and ice adhered on the outer surface of the fin 1 in a short time, shortens a defrost time, and prevents lowering of heat-exchange efficiency.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger having heat exchange tubes through which a refrigerant passes and having heat exchange fins penetrating the heat exchange tubes, and more particularly to a heat pump type air conditioner. The present invention relates to a heat exchanger suitable for use in an outdoor unit.

[0002]

2. Description of the Related Art For example, in a separation type heat pump type air conditioner, an indoor heat exchanger of an indoor unit and an outdoor heat exchanger of an outdoor unit are connected by a refrigerant pipe to circulate a refrigerant. In such a heat exchanger, generally, the heat exchange tubes through which the refrigerant passes are arranged so as to meander,
These heat exchange tubes have heat exchange fins penetrating them. For example, FIG. 7 is a plan view showing a general fin shape, in which plate fins 1 made of a vertically long flat plate are provided with heat exchange tubes 2 penetrating in two rows in a staggered manner. 1 is provided so that the heat transfer area is increased and the heat exchange efficiency is improved.

Such a heat pump type air conditioner is
As is well known, during heating operation, the heat exchanger of the outdoor unit acts as an evaporator, the refrigerant takes heat of the outdoor air to evaporate, and the evaporated refrigerant gas is compressed by the compressor to exchange heat with the indoor unit. The room can be heated by radiating heat with a container. Further, during the cooling operation, the above-mentioned reverse cycle is performed, and the heat exchanger of the indoor unit becomes an evaporator, the refrigerant takes heat of the indoor air to evaporate, and the evaporated refrigerant gas is compressed by the compressor to the outdoor unit. The interior of the room can be cooled by radiating heat with the heat exchanger.

[0004]

By the way, in such an air conditioner, especially when used in a cold region,
During heating operation, frost adheres to the heat exchange tubes and fins of the outdoor heat exchanger that acts as an evaporator, and the adhered frost gradually grows into ice blocks (especially on the windward side that takes in outside air). When frost or ice adheres to the heat exchanger in this way, the heat exchange efficiency decreases and the heating capacity also decreases. Therefore, a defrosting operation that temporarily switches to the same reverse cycle as during the cooling operation described above by a timer etc. and passes the discharge gas (called hot gas) from the compressor through the heat exchange tube to melt frost and ice is performed. Be seen.

However, during this defrosting operation,
Since the heat conduction from the heat exchange tubes is transmitted concentrically on the fins centering on the heat exchange tubes, it is difficult for heat to be transmitted to the end portions 3 which are far from any heat exchange tubes 2 as shown by the diagonal lines in FIG. The defrosting time is long because the frost and ice attached to that part remain until the end. In addition, if heating transmission is performed with frost and ice remaining, heat exchange efficiency decreases, and a problem occurs in which heating capacity cannot be fully exhibited.

Therefore, the present invention has been made in order to solve such a problem, and can shorten the defrosting time,
An object of the present invention is to provide a heat exchanger capable of improving the heating capacity by eliminating frost and ice residue, preventing a decrease in heat exchange efficiency.

Another object of the present invention is to provide a heat exchanger capable of accelerating the fall of frost and ice and shortening the defrosting time.

[0008]

In order to achieve such an object, in the invention described in claim 1 of the present application, heat exchange tubes for passing a refrigerant are arranged, and these heat exchange tubes penetrate. In a heat exchanger having heat exchange fins, at least the windward end portion of the heat exchange fins is formed in a corrugated shape along the cross-sectional shape of the heat exchange tube.

Further, the invention according to claim 2 is a heat exchanger in which heat exchange tubes for passing a refrigerant are arranged in a row, and heat exchange fins are penetrated by the heat exchange tubes. At least the windward end of the fin for use is formed in a corrugated shape along the cross-sectional shape of the heat exchange tube,
The inclined surface below the corrugated concave portion is formed in a linear shape.

Further, the invention according to claim 3 is the heat exchanger according to claim 1 or 2, wherein the tip of the corrugated convex portion is linear. .

According to a fourth aspect of the invention, the heat exchanger according to any of the first to third aspects is used as an outdoor heat exchanger of a heat pump type air conditioner. is there.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

The separation type heat pump type air conditioner to which the heat exchanger according to the present embodiment is applied comprises an indoor unit (not shown) and an outdoor unit 5 as shown in FIGS. Refrigerant is caused to flow in a refrigerant circuit connected by a refrigerant pipe to perform cooling operation and heating operation. The outdoor unit 5 is arranged on the outdoor floor or the like, and exchanges heat with the outdoor air to condense the refrigerant and release heat to the outside air during the cooling operation, and evaporates the refrigerant to take in heat from the outside air during the heating operation.

As shown in FIGS. 1 and 2, the outdoor unit 5 accommodates various refrigerating devices forming a refrigerant circuit in the main body housing 3. That is, a heat exchanger 9 having a substantially L-shape when viewed from above is arranged in the main body housing 3.
A propeller fan 11 for blowing outdoor air to the fan, a fan motor 13, and a support plate 15a for mounting the fan motor 13
15b is accommodated. A fan guard 17 is provided on the panel 16.

As shown in FIG. 2, on the right side in the figure of the outdoor unit 5, a compressor 19, an accumulator 21, a strainer 23, and a compressor 19 which form a refrigerant circuit.
A heater 25 and the like for heating the are provided. Further, various electric components 27 are provided on the upper portion of the outdoor unit 5 in FIG. 2, and the refrigerant circuit and the various electric components 27 are separated from the heat exchanger 9 via a partition plate 29. The main body housing 3 includes a bottom plate 31, outer plates 33 and 34, a top plate 35, a panel 16, and the like. And propeller fan 11
By the rotation of, the outside air is blown to the heat exchanger 9 to perform heat exchange.

According to this embodiment, as shown in FIG. 3, the heat exchanger 9 has a front face portion 40, a side face portion 42, and a heat exchange tube assembly incorporated therein. In the heat exchange tube assembly, a plurality of heat exchange tubes meander and are arranged in a column, and the U-shaped end portion 51 of each path of the heat exchange tube assembly is arranged on the end face side of the side surface portion 42. ing. A large number of heat exchange fins through which the heat exchange tubes arranged in a row pass through are provided with a slight gap from the side surface portion 42 to the front surface portion 40, and the side ends of the heat exchange fins are provided. The part is formed in a corrugated shape.

FIG. 4 shows the fin shape in the first embodiment. In FIG. 3, the heat exchange tubes are arranged in a single vertical line, but in FIG. 4, the heat exchange tubes are shown to clarify the difference from the one shown in FIG. A description will be given of the case where the tubes 2 are arranged in two columns in a staggered manner.

As shown in FIG. 4, in the heat exchange fin 1 of this embodiment, the left and right end portions 1a and 1b are not straight as in the conventional case, but have a corrugated shape along the cross-sectional shape of the heat exchange tube 2. Has been formed. That is, the portion where the heat exchange tube 2 is located becomes a convex portion 1c which is a circle drawn around the tube 2, and the intermediate portion between the upper and lower heat exchange tubes 2 and 2 is a concave portion 1d.

Next, the operation of this embodiment will be described.

As mentioned above, this type of air conditioner
During the heating operation, the heat exchanger 9 of the outdoor unit 5 serves as an evaporator, the refrigerant takes heat of the outdoor air to evaporate, and the evaporated refrigerant gas is compressed by the compressor 19 to be used by the heat exchanger of the indoor unit. The room is heated by radiating heat. Further, during the cooling operation, the above-mentioned reverse cycle is performed, the heat exchanger of the indoor unit serves as an evaporator, the refrigerant takes heat of the indoor air to evaporate, and the evaporated refrigerant gas is compressed by the compressor 19 to be stored outdoors. The interior of the room is cooled by radiating heat with the heat exchanger 9 of the unit 5.

Further, when the defrosting operation is performed in a cold region or the like, a timer or the like is used to temporarily switch to the reverse cycle similar to that in the cooling operation described above, and the hot gas from the compressor 19 is transferred to the heat exchange tube 2. Melt frost and ice through. Here, in the present embodiment, the end portions 1 a, 1 of the heat exchange fin 1 are
Since b is formed in a corrugated shape in accordance with the cross-sectional shape of the heat exchange tube 2 as shown in FIG. 4, the heat conduction from the heat exchange tube 2 spreads over the fins in a short time without gaps. Therefore, the frost and ice attached to the outer surface of the fin 1 can be uniformly melted in a short time, and the defrosting time can be shortened as compared with the conventional case. Further, since frost and ice residue are less likely to occur, it is possible to prevent a decrease in heat exchange efficiency and improve the heating capacity.

FIG. 5 is a diagram showing the fin shape according to the second embodiment, and the overall configuration is the same as that of FIGS. 1 to 3. In the present embodiment, as shown in FIG. 5, both side ends 1a and 1b of the heat exchange fin 1 are formed in a corrugated shape along the cross-sectional shape of the heat exchange tube 2 and below the corrugated concave portion 1d. The inclined surface 1e on the side is formed linearly.

As described above, in cold regions, the frost adheres to the heat exchange fins 1 and the frost gradually grows to become ice, but when it gets worse, not only on the surface of the fins 1 but also from the end to the outside. Ice accretion may occur up to. Especially,
Since the recess 1d is formed in the fin 1 of the embodiment, it seems that icing is likely to occur here. Therefore, as shown in FIG. 5, by forming the inclined surface 1e on the lower side of the concave portion 1d in a linear shape, heat conduction from the heat exchange pipe 2 during defrosting operation weakens the ice accretion with the fins 1. The ice block slides on the linear inclined surface 1e and falls. This allows
It is possible to promote the fall of icing that has occurred on the end face side of the fin 1, and it is possible to further shorten the defrosting time.

FIG. 6 is a diagram showing the fin shape according to the third embodiment, and the overall configuration is the same as that of FIGS. 1 to 3. In the fin shape according to the present embodiment, as shown in FIG. 6, the lower inclined surface 1e of the corrugated concave portion 1d is formed linearly and the tip 1f of the corrugated convex portion 1c is linear. It was made to be done. Therefore, while having the same operation and effect as those of the second embodiment shown in FIG. 5, it can be formed only by providing a predetermined notch in the conventional flat fin 1 shown in FIG. Therefore, it can be realized easily and inexpensively. By the way, making the tip portion 1f of the convex portion 1c linear is also applicable to the first embodiment shown in FIG. 4, and is similarly simple and inexpensive. The effect that can be realized is obtained.

In each of the above-mentioned embodiments, both the windward and leeward end portions 1a and 1b of the fin 1 have a corrugated shape along the cross-sectional shape of the heat exchange tube 2. Since it is likely to occur at the upper end portion and frost and ice are finally left at the time of defrosting, it is also on the windward side. Therefore, even if only the windward end portion is formed into a corrugated shape, a considerable effect can be obtained.

Further, in each of the above embodiments, the case where each invention of the present application is applied to the outdoor heat exchanger of the air conditioner has been described, but it may be applied to the indoor heat exchanger and the air conditioner is cooled. At the time of operation, it has an effect of facilitating water droplets adhering to the fins of the indoor heat exchanger to flow down as drain water.

[0027]

As described above, according to the invention of claim 1 of the present application, at least the windward end portion of the heat exchange fin is formed in a corrugated shape along the cross-sectional shape of the heat exchange tube.
The heat conduction of hot gas during defrosting is improved, the defrosting time is shortened, and frost and ice residue are less likely to occur, so it is possible to prevent a decrease in heat exchange efficiency and improve heating capacity. There is an effect that can be done.

According to the second aspect of the present invention, at least the windward end portion of the heat exchange fin is formed in a corrugated shape along the cross-sectional shape of the heat exchange tube, and the bottom portion of the corrugated concave portion is formed. Since the inclined surface on the side is formed in a linear shape, the same effect as that of the above-mentioned claim 1 can be obtained, and frost and ice remaining in the concave portion can easily slide down the linear inclined surface. This has the effect of promoting falling and further shortening the defrosting time.

Further, according to the invention of claim 3, since the tip of the corrugated convex portion is formed in a straight line shape, the same effect as in claim 1 or 2 can be obtained. Since it can be formed only by providing a predetermined notch in the conventional plate-shaped fin, there is an effect that it can be realized easily and at low cost.

Further, according to the invention of claim 4, since the heat exchanger as described above is used as an outdoor heat exchanger of a heat pump type air conditioner, frost formation or frost formation which is a weak point of the heat pump type. There is an effect that defects caused by ice can be efficiently improved.

[Brief description of drawings]

FIG. 1 is a front view showing an outdoor unit of an air conditioner to which a heat exchanger according to the present invention is applied.

FIG. 2 is a perspective view showing an example of an internal structure of the outdoor unit.

FIG. 3 is a perspective view showing a heat exchanger and the like of the outdoor unit.

FIG. 4 is a plan view showing a fin shape according to the first embodiment of the present application.

FIG. 5 is a plan view showing a fin shape according to the second embodiment.

FIG. 6 is a plan view showing a fin shape according to the third embodiment.

FIG. 7 is a plan view showing a fin shape of a conventional heat exchanger.

[Explanation of symbols]

 1 heat exchange fin 1a, 1b end part 1c convex part 1d concave part 1e inclined surface 1f tip part 2 heat exchange tube 5 outdoor unit 9 heat exchanger

Claims (4)

[Claims] 1. A heat exchanger having heat exchange fins for arranging heat exchange pipes through which the refrigerant passes, wherein at least windward end portions of the heat exchange fins are heat-exchanged. A heat exchanger characterized by being formed in a corrugated shape along the cross-sectional shape of a tube. 2. A heat exchanger having heat exchange tubes through which the refrigerant passes and which are arranged in tandem, and which has heat exchange fins penetrating the heat exchange tubes, wherein at least the windward end portion of the heat exchange fins is provided. A heat exchanger characterized in that it is formed in a corrugated shape along the cross-sectional shape of a heat exchange tube, and a lower inclined surface of the corrugated concave portion is formed in a linear shape. 3. The heat exchanger according to claim 1, wherein a tip of the corrugated convex portion is linear. 4. The heat exchanger according to any one of claims 1 to 3, which is used as an outdoor heat exchanger of a heat pump type air conditioner.