JPH0682189A - Heat exchanger - Google Patents

Abstract

PURPOSE:To provide a heat exchanger in which times to cut down defrosting water and condensation water are effectually shortened, and in which the strength and an assembling property are improved. CONSTITUTION:Through-holes 14 penetrating a refrigerant piping are formed through many parallel plate fins 2 of a heat exchanger composed of the plate fins 2 disposed at a specified interval and of the refrigerant piping. An annular part 16 is formed around the through-hole 14, the annular part 16 constructing an interval between the adjacent plate fins 2. Substantially the entire region of the plate fin 2 excepting the annular part 16 but including the upper and lower portions of the annular part 16 are formed into a corrugated configuration comprising crests and vallyes both extending vertically. An aluminum plate in which a groove of the same configuration is formed is superimposed on the brazing sheet 1, and both are joinned with each other through melting of the brazing material 8. A fluid passage is hereby formed with the aid of both of the brazing sheet 1 and the aluminum plate, and a cooling plate is cooled directly by a fluid refrigerant flowing through the fluid passage for highly effectual heat transfer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger used in a refrigerator, a freezing / refrigerating showcase, an air conditioner or the like.

[0002]

2. Description of the Related Art Conventionally, this type of heat exchanger is disclosed in, for example, Japanese Patent Publication No.
As disclosed in Japanese Patent Publication No. 3-46498 (F28F1 / 32), a plurality of heat exchanging plate fins are arranged in parallel at a predetermined interval, and insertion holes are formed in these plate fins. A refrigerant pipe is inserted through this insertion hole and attached. Then, the decompressed refrigerant is supplied to the refrigerant pipe, and evaporates there to absorb heat from the surroundings, whereby the heat exchanger exhibits a cooling effect.

Since this cooling action causes frost and dew condensation on the heat exchanger, the ventilation resistance of the heat exchanger is increased and the heat exchange performance thereof is deteriorated. Therefore, this kind of heat exchanger periodically stops the cooling operation and is defrosted by the heating means. However, when defrosting water or the dew condensation water generated by defrosting remains on the plate fins, it freezes and grows at the next cooling, which promotes the increase of the ventilation resistance and the deterioration of the heat exchange performance. Water droplets must be removed reliably. On the other hand, it is not possible to continue defrosting for a long time and stop the cooling operation for such drainage in view of the storage performance of food and the like, so draining must be performed reliably and promptly.

In view of this, in the above publication, a vertical groove is formed in the plate fin so that drops of dew condensation water or defrosting water adhering to the plate fin can be collected in the groove and easily fall.

[0005]

Here, frost and dew condensation attach and grow around the refrigerant pipe where the temperature is the lowest. However, in the above publication, since there is no groove above and below the tube hole through which this refrigerant pipe is inserted, it is not possible to quickly remove the water droplets around the tube hole, and there is a problem that the shortening of the draining time does not improve as expected. there were.

Moreover, since the height of the annular portion existing around the tube hole is low (about 6.5 mm in the prior art), there is no effect of maintaining the distance between the plate fins, and a predetermined distance is preliminarily set when the heat exchanger is manufactured. There was no other method than using a special jig for holding the plate fin and inserting the refrigerant pipe into the hole while holding the plate fin on the jig. The present invention has been made to solve the above-mentioned conventional technical problems, effectively shortens the draining time of defrost water and dew condensation water, and improves strength and assembly workability. It is an object of the present invention to provide a heat exchanger designed.

[0007]

The heat exchanger 1 of the present invention comprises:
A large number of plate fins 2 arranged in parallel at a predetermined interval and a refrigerant pipe 1 penetrating these plate fins 2.
2 and the plate fin 2 is formed with an insertion hole 14 for inserting a refrigerant pipe, and an annular portion 16 is formed around the insertion hole 14 to form an interval between the plate fins 2. It is characterized in that substantially the entire area of the plate fin 2 other than the annular portion 16 including the upper and lower sides is formed into a wave shape composed of peaks and valleys extending in the vertical direction.

[0008]

According to the heat exchanger 1 of the present invention, water droplets such as defrosting water or condensed water adhering to the plate fins 2 are collected due to the wave shape of the plate fins 2 and the weight becomes heavy and the peaks and valleys spread. It quickly drops downward in the current direction. Particularly, since the upper and lower portions of the annular portion 16 around the insertion hole 14 through which the refrigerant pipe 12 is inserted are also wavy, defrosting water and dew condensation water in which a large amount of frost adhering to the refrigerant pipe 12 is melted are also plate fins 2. After that, it quickly drops downward, which is also the direction of extension of the peaks and valleys. As a result, the time for draining defrost water and condensed water is significantly shortened.

Further, the corrugated shape improves the strength of the plate fin 2 and corrects its distortion and the like, and the surface area of the plate fin 2 can be increased, so that the overall width of the plate fin 2 is reduced. The heat exchanger 1 can be made thin. In particular, since the annular portion 16 configures the gap between the plate fins 2 in the stacked state, the heat exchanger 1 can be inserted only by inserting the refrigerant pipe 12 in the stacked state of the plate fins 2 without using a jig. Can be assembled.

[0010]

Embodiments of the present invention will now be described with reference to the drawings. 1 is a perspective view of a plate fin 2 of a heat exchanger 1 of the present invention, FIG. 2 is a partially cutaway perspective view of a low temperature showcase 3, and FIG. 3 is a perspective view of the heat exchanger 1. In FIG. 2, the low temperature showcase 3 of the embodiment is a so-called refrigerating open showcase having an opening on the front side, and a partition plate 6 is attached to the inside of a heat insulating wall 4 having a substantially U-shaped cross section at a distance. A cold air passage 7 is formed between the partition plate 6 and the heat insulating wall 4, and a storage chamber 8 for displaying products such as food is formed inside the partition plate 6. In addition, a shelf 9 for displaying products is provided in the storage room 8.
Are installed in multiple stages.

A heat exchanger 1 of the present invention, which serves as a cooler, is vertically installed in a cold air passage 7 located behind the storage chamber 8, and the cool air passage 7 is blown from the bottom to the top by a blower (not shown). Air is circulated through. As a result, the cold air that has exchanged heat with the heat exchanger 1 rises in the cold air passage 7 and is blown out into the storage chamber 8 from the discharge port (not shown) located at the upper edge of the opening, forming an air curtain in the opening and storing it. After circulating in the chamber 8, it returns to the cold air passage 7 from a suction port (not shown) at the lower edge of the opening. Due to such cold air circulation, the inside of the storage chamber 8 is cooled to a predetermined refrigerating temperature.

Here, as shown in FIG. 3, the heat exchanger 1 has a plurality of rectangular plate fins 2 made of aluminum, which are arranged in parallel with each other at a predetermined interval, and meanders through the plate fins 2. The refrigerant pipe 12 is made up of copper pipes and is arranged at both ends of the plurality of plate fins 2 to hold the bend portion of the refrigerant pipe 12. The outer diameter of the refrigerant pipe 12 is 1/2 inch in the embodiment, and the plate fins 2 are made of an aluminum thin plate having a thickness of 0.25 mm, and have a shape as shown in FIG. 1 as a whole. There is.

That is, a plurality of insertion holes 14 for inserting the refrigerant pipe 12 in the plate fin 2, an annular portion 16 located around the insertion hole 14 and standing upright from the plate fin 2, and the annular portion. 16 is formed around the base of the annular portion 16, and the entire plate fin 2 outside the flat portion 17 including the upper and lower sides of the annular portion 16 is formed in a wave shape composed of peaks and valleys extending in the vertical direction. There is.

The procedure for forming the plate fin 2 will be described. First, a suitable place of a flat plate-shaped aluminum thin plate is lifted and punched by several stages of drawing, and the standing dimension of the annular portion 16 is increased by several stages of ironing. go. The upright dimension is enlarged to about 10 mm so that the annular portion 16 can maintain the distance between the plate fins 2 and 2 and the tip of the annular portion 16 is curled outward.
At this time, the inner diameter of the annular portion 16 is approximately equal to the outer diameter of the refrigerant pipe 12. Next, an upper and lower metal mold having an overall corrugated shape that is circularly removed with a diameter of a predetermined width around the annular portion 16 is prepared, and the annular portion 16 is positioned between the upper and lower die parts while the annular portion 16 is positioned at the deleted portion. A thin aluminum plate is sandwiched to form a corrugated shape with the flat surface portion 17. At this time, the interval between the peaks of the corrugations is 10 mm, and the dimension between the peaks of the peaks and valleys is 2 mm. The corrugation corrects the distortion of the plate fin 2 and also improves the strength of the plate fin 2 itself.

Next, the procedure for assembling the heat exchanger 1 will be described. First, a plurality of plate fins 2 formed as described above are stacked. At this time, the annular portion 1 of the plate fin 2
The tip of 6 abuts on the back surface of the flat surface portion 17 of the plate fin 2 which faces, but the standing dimension of the annular portion 16 is 10 mm.
Therefore, the plate fins 2 can be formed only by such stacking.
The mutual space is sufficiently secured. In this way, the plate plates 2 are arranged with the plate fins 2 stacked, and then the refrigerant pipes 12 are inserted into the insertion holes 14 and finally the refrigerant pipes 12 are expanded so that the plate fins 2 are brought into close contact with each other. Complete. Therefore, unlike the prior art, a jig for securing the space between the plate fins 2 during assembly is unnecessary. At this time, since the annular portion 16 adheres to the periphery of the outer surface of the refrigerant pipe 12 with a wide width of 10 mm, the plate fin 2 and the refrigerant pipe 1
The heat conduction performance of No. 2 is improved.

The heat exchanger 1 thus assembled is arranged in the cold air passage 7 of the low temperature showcase 3 so that the peaks and valleys of the plate fins 2 extend in the vertical direction. At this time,
Since the plate fin 2 has a substantially wavy shape, its front-rear width is reduced with the same surface area. Therefore, since the heat exchanger 1 is thinned, the depth of the cold air passage 7 can be reduced, and thus the depth dimension of the storage chamber 6 can be increased. Air flows through the heat exchanger 1 from the bottom to the top as described above, but the distance between the peaks of the corrugations of the plate fins 2 is 10 mm, and the dimension between the peaks of the peaks and valleys is Since it is as small as 2 mm, deterioration of ventilation resistance can be minimized.

The reduced pressure refrigerant is supplied to the refrigerant pipe 12 of the heat exchanger 1 and evaporates inside, so that the heat exchanger 1 exhibits a cooling effect. By such cooling operation, the heat exchanger 1
Condensation and frost will grow on. Such dew condensation is caused by so-called off-cycle defrosting or frosting is melted and removed by heating with an electric heater while the cooling operation is stopped. The fins 2 gather in the valley-shaped portions and become heavy in weight, and as shown in FIG. 4, they quickly drop downward in the extending direction. In particular, water droplets W that have moved to the plate fins 2 from the annular portion 16 of the refrigerant pipe 12 where dew condensation and frost are most concentrated are also collected in the valley-shaped portions located therebelow and fall, so that the heat exchanger 1 Draining time is significantly shortened. Therefore, the total time spent for defrosting the heat exchanger 1 can be shortened, so that the deterioration of the product due to the stop of the cooling operation can be suppressed.

Although the heat exchanger 1 of the present invention is applied to the low temperature showcase 3 in the embodiment, the heat exchanger 1 of the present invention is not limited to this and is also effective for a refrigerator or an air conditioner. Further, in the embodiment, the peaks and troughs of the plate fins 2 are arranged so as to extend in the vertical direction, but depending on the shape of the cold air passage, it may be slightly inclined, and the water droplets W may be vertically dropped so as to easily drop. As long as it extends, it does not deviate from the gist of the present invention.

[0019]

As described above in detail, according to the present invention, water droplets such as defrosting water or dew condensation water adhering to the plate fins are collected due to the wave shape of the plate fins, and the weight of the plate fins becomes heavy, resulting in the formation of peaks and valleys. It rapidly falls downward, which is the extending direction, and the upper and lower portions of the annular portion around the insertion hole through which the refrigerant pipe is inserted are also wavy, so a large amount of frost adhering to the refrigerant pipe has melted. After the frost water and the condensed water also move to the plate fins, they also quickly drop downward in the extending direction of the mountains and valleys. Therefore, it is possible to remarkably shorten the drainage time of defrosting water or dew condensation water, thereby shortening the defrosting time, and suppressing deterioration or the like of the cooled article.

Further, the corrugated shape improves the strength of the plate fin, corrects its distortion and the like, and increases the surface area of the plate fin, so that the overall width of the plate fin is reduced and the heat exchanger is reduced. Can be made thinner.
In particular, since the annular portion configures the intervals between the plate fins in a stacked state, it is possible to assemble the heat exchanger simply by inserting the refrigerant pipes in the stacked plate fins without using a special jig. Therefore, the workability of assembling the heat exchanger can be significantly improved.

[Brief description of drawings]

FIG. 1 is a perspective view of plate fins of a heat exchanger of the present invention.

FIG. 2 is a partially cutaway perspective view of a low temperature showcase as an example.

FIG. 3 is a perspective view of the heat exchanger of the present invention.

FIG. 4 is a perspective view of plate fins for explaining a state of water drops falling.

[Explanation of symbols]

 1 Heat Exchanger 2 Plate Fin 12 Refrigerant Pipe 14 Insertion Hole 16 Annular Section

Claims (1)

[Claims] 1. A heat exchanger comprising a plurality of plate fins arranged in parallel at a predetermined interval and a refrigerant pipe penetrating the plate fin, wherein an insertion hole for inserting the refrigerant pipe is provided in the plate fin. Along with the formation, an annular portion is formed around the insertion hole to form a space between the plate fins, and substantially the entire area of the plate fin other than the annular portion including the upper and lower portions of the annular portion extends in the vertical direction. A heat exchanger characterized by having a wave shape composed of peaks and valleys.