JPH0435672B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a fin and tube type heat exchanger for forced ventilation in refrigerators, etc., and improves heat exchange by bending the ends of the fins when installing a defrosting heater. The purpose is to combine the holding power of the defrosting heater with the holding power of the defrosting heater.

Recently, in order to improve the heat exchange efficiency in the evaporator from the viewpoint of energy saving, the fins have been separated and independent in the ventilation direction, and the fins have been separated to achieve this purpose due to the boundary layer leading edge effect. It has come to be used in refrigerators, etc.
However, although such an independent fin type evaporator has very high heat exchange efficiency, frost formation is noticeable at the ends of the independent fins, that is, the end surfaces of the fins that come into contact with the circulating air, which makes it difficult to use the conventional continuous plate fins. On the other hand, simply applying a configuration in which the heater is placed on the upper edge (or lower edge) side does not sufficiently defrost the end face, and it becomes necessary to increase the heat output of the heater in order to achieve sufficient defrosting. There were some shortcomings.

Therefore, the present invention improves the defrosting effect by improving the adhesion of the defrosting heater at the edge of the independent fin, and furthermore, in addition to the leading edge effect of the boundary layer due to the independent fin, the turbulent flow is improved without adding any new processing in advance. This was accomplished with the aim of improving the heat exchange efficiency through this effect, and one embodiment thereof will be described below with reference to the accompanying drawings.

In the figure, 1 is the evaporator (heat exchanger) main body as a cooler of the refrigerator-freezer, and the end plates 2 and 3 on both sides are spaced between each column a, b, c, and d. A large number of fin plates 4a, 4b, 4 arranged in parallel at approximately equal intervals.
fin plates 4a, 4b, 4c, and 4d extending over these end plates 2 and 3, and a refrigerant tube 5 that is meanderingly inserted orthogonally through the fin plates 4a, 4b, 4c, and 4d.

The fin plates 4a, 4b, 4c, and 4d in each of the above-mentioned rows a, b, c, and d are arranged so that the fin pitches thereof become sequentially from sparse to dense in the air flow direction (indicated by arrows in FIG. 1). Moreover, between the fins in each row, that is, between the fins 4a and 4b, between the fins 4b and 4c,
There is a slight gap r between the fins 4c and 4d.
have. That is, by providing independent fins 4a, 4b, 4c, and 4d for each row of refrigerant tubes 5 in the air flow direction, the air contact opportunities at the fin edges are increased (boundary layer leading edge effect). Improves heat exchange efficiency.

On the other hand, 6 is a defrosting heater such as a pipe disposed inside the evaporator main body 1, which comes into contact with the fins 4a, 4b, 4c, and 4d to remove frost attached to the fins. This heater 6 is previously formed into a U-shape, and the U-shaped tip 6' is inserted into the gap through an insertion hole 7 bored at a position facing the gap r between the fins of one end plate 2. It is something that will be done. The diameter R of the defrosting heater 6 is slightly larger than the gap r, so if the heater 6 is inserted through the insertion hole 7 as described above, the fin 4
Among the tubes a, 4b, 4c, and 4d, the side that contacts the heater 6 bends around the tube 5 as a fulcrum. Further, fins 4a, 4b forming the gap r,
Since obtuse-angled flanges 4a' and 4b' are formed at the ends of 4c and 4d, they are brought into close contact with the surface of the heater 6.

As is clear from the above explanation, according to the present invention, the bent portions of the fins create turbulence in the ventilation air flowing from the windward side to the leeward side, and together with the leading edge effect of the boundary layer, the efficiency is greatly improved. In addition, a heater is installed between the independent fins where frost builds up, making it highly effective in defrosting. In addition, since the bends in the fins are not formed in advance but are formed by inserting the heater, the fins need only be easily arranged when inserting the fin heave, and the assembly process can be reduced. It is also good.

[Brief explanation of drawings]

FIG. 1 is a plan view of a heat exchanger manufactured according to the invention, FIG. 2 is an enlarged sectional view of the main parts, FIG. 3 is a side view before insertion of the heater, and FIG. 4 is a perspective view of the fins. 4a, 4b, 4c, 4d...Fin, 5...Tube, 6...Heater, r...Gap.

Claims (1)

[Claims] 1. In a heat exchanger consisting of a large number of fins and tubes inserted through the fins, the fins are separated and independent from the row of tubes in the ventilation direction, and a predetermined gap is provided between the separate and independent fins. A method for manufacturing a heat exchanger, characterized in that a heater having a diameter slightly larger than the gap is inserted from the side into the gap, and the fins are bent when inserted.