JPS60228893A - Fin tube type heat exchanger - Google Patents

Abstract

PURPOSE:To obtain the fin tube type heat exchanger making a good use of the characteristics of an elliptic pipe sufficiently in case the flow direction of air is different depending on a place by a method wherein the directions of the major axes a multitude of pipes having elliptic sections are arranged so as to be coinciding with the flow directions of the air. CONSTITUTION:A multitude of fins 13 is laminated so that the directions E1- E1', E2-E2'... of major axes of respective elliptic holes 15 are coinciding with the flow directions of air in the condition that the fin tube type heat exchanger is used and the fin tube type heat exchanger is formed by inserting the elliptic tubes 16 into the holes 15. As a result, the prominent characteristic of the fin tube type heat exchanger, in which dead water areas C are reduced and airflow resistance is decreased, may be obtained allover the whole area of the heat exchanger.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a fin-tube heat exchanger used in air conditioners and the like.

Structure of the conventional example and its problems A conventional fin-tube heat exchanger has a large number of stacked fins 1 made of aluminum or copper thin plates as shown in Figs. 1 and 2. The copper tube 2 is passed through the hole 6 of the fin 1 shown in FIG.
A curled collar part 7 raised up around the hole 6 is brought into close contact with the hole 6, and a U-bend pipe 3 and an inlet/outlet pipe 4 as required depending on the circuit shape are connected. Reference numeral 6 denotes a side plate made of steel plate for maintaining mechanical strength and fixing the entire fin-tube heat exchanger. The copper tube 2 is a thin-walled steel tube with a circular cross section processed into a hairpin shape as shown in FIGS. 3 and 4, and the fin 1 is a hairpin of the copper tube 2 as shown in FIGS. 5 and 6. Each pitchle has a circular hole 6 with an inner diameter d slightly larger than the pipe diameter of the copper tube 2, with the collar portion 7 raised up.

In the fin-tube heat exchanger using steel pipes with a circular cross section configured as described above, the air flow in the copper pipe winding on the fin surface is as shown by the arrow in FIG. The area where air flow is inactive, the so-called dead zone (No. 7
The area shown by diagonal lines in Figures to Figure 9) has the disadvantage that heat exchange in this area becomes inactive due to the formation of heat exchange in this area, so recently copper tube 2 and collar 71r: fin tube type heat exchanger has been changed to an elliptical shape. The device is being put into practical use. In this case, the air flow on the surface of the fins 10 flows along the elliptical tube 8 and the elliptical collar part 9 as shown in FIG. 8, so the area of the dead area is significantly reduced and the heat exchange efficiency is improved accordingly It had a certain effect. In addition, the elliptical tube had better characteristics than the fin-tube heat exchanger using the circular tube, such as clearly reducing air flow resistance compared to the circular tube.

However, as is clear from the above explanation, this excellent characteristic is obtained when the direction of air flow coincides with the long axis direction of the elliptical tube; if these two directions are misaligned, the 9th As shown in the figure, a large dead area d and large air flow resistance will occur.

However, when looking at the cross section of a conventional fin-tube heat exchanger using elliptical tubes, as shown in Figure 10, the long axes D1 to D1', D2 to D2', etc. of each elliptical tube are all parallel. Therefore, if the air flow direction is all parallel as shown by arrow A in Figure 1 and horizontal in Figure 1, the above elliptical tube can be used in a fin-tube heat exchanger. However, for example, when the air blower 12 is provided above as shown in Fig. 11, and the direction of air flow in the fin-tube heat exchanger 11 differs depending on the location (as shown by the dotted line arrow B in Fig. 1), ), there may be some areas that look like the dead area C in Figure 8, but there will also be areas that look like the dead area shown in Figure 9, and the above-mentioned elliptical tubes can be used in fin-tube heat exchangers. The drawback was that the excellent properties of the methane were not fully utilized.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional drawbacks, and aims to provide a fin-tube heat exchanger that makes full use of the characteristics of elliptical tubes when the direction of air flow differs depending on the location.

Structure of the Invention The present invention comprises a fin made of a thin aluminum or copper plate having a number of elliptical holes with a curled collar portion around the periphery, and a number of tubes having an elliptical cross section. , a fin-tube heat exchanger manufactured by laminating a large number of fins, inserting a limb through the elliptical hole, and expanding the limb from the inside; The direction of the long axis is made to match the direction of air flow when the fin-tube heat exchanger is used.

DESCRIPTION OF EMBODIMENTS An embodiment according to the present invention will be described with reference to FIGS. 12 and 13. FIGS. 12 and 13 are assembly diagrams of fins and tubes in one embodiment of the present invention, and correspond to FIGS. 3, 6, and 10 in the description of the conventional example. In the figure, 13 is a fin formed from a thin plate of aluminum or copper, 14 is an oval hole, and 15 is a part of a curled collar raised around the oval hole, and the long axis of each oval is The directions E, ~E1', E2~E2', . . . are taken to correspond to the air flow direction when this fin-tube heat exchanger is used. The manufacturing of a fin-tube heat exchanger by stacking a large number of fins 13 and inserting elliptical tubes 16 is the same as in the conventional example, so a detailed explanation will be omitted.

In the above configuration, the direction of the long axis of each tube is made to match the direction of air flow at each position as described above. Even if the air flow direction is different for each tube due to the positional relationship, the air flow indicated by arrows for all tubes 16 follows their long axes E1 to E1' as shown in FIG.
, E2-E2'.

E3 to E3' and E4 to E4' are parallel to each other, and the excellent performance of the fin-tube heat exchanger using oval tubes, such as reduction of dead area C and reduction of air flow resistance, is achieved by the heat exchanger. Effects of the Invention As described above, in the fin-tube heat exchanger of the present invention, the direction of air flow is made to coincide with the long axis direction of the elliptical shape in all the elliptical tubes. Therefore, it is possible to reduce dead areas and air flow resistance around all pipes without causing problems such as an increase in dead areas or an increase in air flow resistance in the downstream area of the pipes. The characteristics obtained with a fin-tube heat exchanger using elliptical tubes can be exhibited throughout the entire area of the heat exchanger.

[Brief explanation of drawings]

Figure 1 is a side view of the fin-tube heat exchanger in the description of the conventional example, Figure 2 is the front view, Figure 3 is the side view of the same hairpin-shaped steel pipe, Figure 4 is the front view, and Figure 4 is the front view of the same. Figure 5 is a side view of the same fin, Figure 6 is a front view of the same, Figure 7 is a diagram showing the state of air flow on the surface of the fin when a tube with the same circular cross section is used, and Figure 8 is the same oval shape. Figure 9 is a diagram showing a case where a tube with the same elliptical cross section is used. FIG. 11 is an explanatory diagram of how air flows in the equipment when the fin-tube heat exchanger is used, and FIG. 12 is a cross-sectional view of the fin-tube heat exchanger according to an embodiment of the present invention. FIG. 13 is a partially sectional side view of the type heat exchanger. E1-E1', E2-E2'...Direction of the long axis of the ellipse, 13...Fin, 14...Oval hole, 15...・Rising part, 16...
...A steel pipe with an elliptical cross section. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 0Figure 11

Claims (1)

[Claims] Made of a thin aluminum or copper plate with a large number of elliptical holes formed in a curled manner around the periphery, with the direction of the long axis of each ellipse aligned with the direction of air flow at the position of each ellipse. and a tube having an elliptical cross section with an outer dimension slightly smaller than the inner dimension of the hole, a plurality of the fins are stacked, and the tube that penetrates the hole is expanded and brought into close contact with the fin. fin-tube heat exchanger.