JP2017083041A - Heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem found in a case when a projecting portion is shortened, that a time to clogging of a ventilation passage is shortened in comparison with a conventional one, as a distance from a heat transfer tube, of a windward-side tip of the projecting portion is short, and a temperature may be same as the heat transfer portion, which causes easy attachment of frost to the windward-side tip of the projecting portion.SOLUTION: A fin has a heat transfer portion configuring a ventilation passage, and a projecting portion projecting to a windward side with respect to the heat transfer portion. The projecting portion has a hole portion formed from an upper portion to a lower portion, an upper tab extending toward an adjacent fin is formed on an upper end of the hole portion, and a lower tab extended toward an adjacent fin is formed on a lower end of the hole portion. The upper tab and the lower tab are formed by cutting and raising a part of the fin while applying the upper end or the lower end of the hole portion as a fold. Further louvers inclined to the ventilation direction are respectively formed on both ends at a windward side and a leeward side of the hole portion.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a heat exchanger that includes a heat transfer tube and fins and exchanges heat between fluid flowing in the heat transfer tube and air.

  A heat exchanger provided with a heat transfer tube and fins is known. In this heat exchanger, a plurality of plate-like fins are stacked in parallel at a predetermined interval. A plurality of heat transfer tubes inserted so as to be orthogonal to the stacked fins are arranged side by side at regular intervals. Tabs formed by cutting and raising a part of the fins are provided on the windward side and the leeward side of the fin surface in order to adjust the spacing between the fins.

  The part between the heat transfer tubes adjacent on the top and bottom of the surface of each fin is a heat transfer unit that conducts heat between the air and the heat transfer tubes. When the heat exchanger is used as an evaporator, the fins are cooled by the refrigerant flowing through the heat transfer tubes. Therefore, if the heat transfer tubes are below freezing, frost adheres to the surface of the fins, and if the amount of frost adhering is large, the fins And block the ventilation path surrounded by the heat transfer tube. Therefore, in order to delay the time until the frost adheres to the heat transfer part, particularly the heat transfer part among the fins, a protruding part formed by protruding a part of the fin to the windward side from the heat transfer tube is provided. . Since the tip of the windward side of the protruding portion is sufficiently long from the heat transfer tube, the temperature does not decrease as the heat transfer portion, and the time until frost is attached is delayed as the air passage is blocked. Further, since the temperature of the protruding portion decreases as it approaches the heat transfer portion, before the wind exchanges heat with the heat transfer portion, heat can be exchanged with the protruding portion to reduce moisture in the wind. Thereby, the time until the ventilation path formed surrounded by the fin and the heat transfer tube is blocked by frost is delayed. (See Patent Document 1)

JP 2015-31485 A JP 2006-292336 A

  In order to increase the heat exchange capacity of the heat exchanger, two heat exchangers may be used side by side (in two rows) in the ventilation direction. In this case, if there is a protruding portion of the fin, the thickness of the heat exchanger in the ventilation direction may increase. Therefore, the protrusion part of each heat exchanger is shortened compared with the case where it uses by a heat exchanger single-piece | unit (1 line).

  When the protruding portion is shortened as in the above example, the distance between the tip of the protruding portion on the windward side and the heat transfer tube is shortened, so that the temperature difference from the heat transfer portion is reduced. For this reason, frost tends to adhere to the tip of the windward side of the protruding portion, and there is a possibility that the time until the ventilation path is blocked is shortened as compared with the conventional case.

  Therefore, in order to weaken the heat transfer from the heat transfer tube, it is conceivable to apply a method of forming a slit (hole) in the fin (see Patent Document 2) on the leeward side of the protruding portion. By the way, since it is necessary to keep the space | interval of a fin constant, the tab formed by cutting and raising a part of fin is provided near the windward front end of the fin. Therefore, in a fin having a protruding portion at the windward tip, it is necessary to provide a slit and a tab at the protruding portion at the same time. However, when the protruding portion is shortened to reduce the thickness of the heat exchanger, there is a problem that there is no room for forming both the slit and the tab in the protruding portion.

  Then, an object of this invention is to provide the heat exchanger which can form both a slit and a tab even with a short protrusion part.

  In order to solve the above-described problem, the present invention provides a plurality of heat transfer tubes arranged vertically and a plurality of plate-like fins arranged crossing the plurality of heat transfer tubes and arranged side by side. A heat exchanger having a heat pipe and a plurality of ventilation paths surrounded by fins adjacent to the left and right, wherein the fins are a heat transfer part that forms the ventilation path, and a protruding part that protrudes further to the windward side than the heat transfer part The protrusion has a hole formed from the upper part to the lower part, an upper tab extending toward the adjacent fin is formed at the upper end of the hole, and the adjacent fin is formed at the lower end of the hole. A lower tab was formed extending toward.

  Further, the upper tab and the lower tab are obtained by cutting and raising a part of the fin by folding the upper end or lower end of the hole.

  In addition, louvers that are inclined with respect to the ventilation direction are formed on both the windward side and the leeward side of the hole.

  According to the heat exchanger of the present invention, both the hole and the tab can be formed even with a short protruding portion.

It is the perspective view which showed the whole heat exchanger concerning this invention. It is the front view which showed the whole heat exchanger concerning this invention. FIG. 3 is a cross-sectional view taken along a cutting line AA in FIG. 2. It is sectional drawing in the cutting line BB of FIG. 3, and the cutting line CC. It is sectional drawing which showed the detail of the protrusion part concerning this invention. It is sectional drawing in the cutting line AA of FIG. 2 concerning another embodiment of this invention. It is sectional drawing which showed the detail of the protrusion part concerning another embodiment of this invention.

  A heat exchanger 100 according to an embodiment of the present invention is a heat exchanger including fins 120 and flat tubes 130 as shown in FIGS. 1 and 2.

  The heat exchanger 100 includes a first header 110a, a second header 110b, a plurality of flat tubes 130, and a plurality of fins 120. The first header 110a, the second header 110b, the flat tube 130, and the fin 120 are all members made of aluminum alloy, and each joint is performed by brazing.

  Both the first header 110a and the second header 110b are formed in an elongated cylindrical shape whose both ends in the longitudinal direction are closed. The first header 110 a is disposed on one end side of the heat exchanger 100, and the second header 110 b is disposed on the other end side of the heat exchanger 100. Note that the longitudinal direction of each of the first header 110 a and the second header 110 b is the vertical direction of the heat exchanger 100.

  The flat tube 130 is a heat transfer tube whose cross-sectional shape is an oval or a rounded rectangle, and extends in a direction perpendicular to the fins 120. The flat tube 130 is provided with a plurality of refrigerant channels through which the refrigerant flows. The refrigerant channel extends between one end and the other end of the flat tube 130 from one end to the other end in the longitudinal direction. Formed and arranged at equal intervals in the width direction of the flat tube 130. In the heat exchanger 100, each flat tube 130 is an interval determined in consideration of the heat exchange efficiency and the ventilation resistance of the heat exchanger 100 so that the upper surface and the lower surface face each other. They are arranged side by side at an interval d1 of 1. Each flat tube 130 has one end inserted into the first header 110a and the other end inserted into the second header 110b. The longitudinal direction of the flat tube 130 is the left-right direction.

  The fin 120 is formed into a vertically long plate shape by pressing a metal plate. As shown in FIG. 3, the fin 120 has a horizontally long notch 140 extending from one end in the short direction of the fin 120 toward the other end in the short direction of the fin 120. ) At a predetermined interval. When the flat tube 130 is inserted into the notch 140, the flat tube 130 is arranged at a first interval d1 in the vertical direction. Further, as shown in FIG. 1, the fin 120 has a second interval d2 that is an interval determined in consideration of the heat exchange efficiency and the ventilation resistance of the heat exchanger 100 in the longitudinal direction (left and right direction) of the flat tube 130. A plurality of sheets are arranged. As shown in FIG. 2, a plurality of ventilation paths 150 surrounded by flat tubes 130 adjacent in the vertical direction and fins 120 adjacent in the horizontal direction are formed side by side in the vertical direction and the horizontal direction. In FIG. 2, one of the plurality of ventilation paths 150 is shown as a representative. The fins 120 and the flat tubes 130 are orthogonal to each other. As shown in FIG. 3, the fins 120 and the flat tubes 130 are in contact with one of a plurality of ventilation paths on the surface of the fins 120 and between the flat tubes 130 adjacent to each other in the vertical direction. The surface becomes the heat transfer section 121 that exchanges heat with the air indicated by the hatched arrows. Further, the surface on the other end side from the notch portion 140 becomes a flowing water portion (communication portion) 122 formed continuously from the upper end 120 a to the lower end 120 b of the fin 120. The side with the hatched arrow is the windward side, and the opposite side is the leeward side.

  The heat transfer portion 121 of the fin 120 is provided with a protruding portion 150 that protrudes by extending a part of the fin 120 to the windward side of the flat tube 130. The projecting portion 150 has the same thickness as the fin 120 and is formed in a rectangular shape having a length L of about 4 mm in the ventilation direction.

  The protruding portion 150 is provided with a hole portion 191. Tabs 161 and 162 and louvers 181 and 182 are provided around the hole 191. The hole 191 is a hole that connects the upper part and the lower part of the protruding part 150. The upper tab 161 and the lower tab 162, which are the windward side tabs, are plate-like cut and raised pieces formed by cutting and raising the fins 120, and are shown in FIG. As shown, it is formed so as to be parallel to the ventilation direction and to be perpendicular to the fin 120. The louvers 181 and 182 are plate-like cut and raised pieces formed by cutting and raising the fins 120. The louvers 181 and 182 are formed on the windward and leeward ends of the hole portion 191 with respect to the ventilation direction as shown in FIG. For example, it is formed so as to be inclined about 5 degrees. The upper tab 161 and the lower tab 162 are oriented in the same direction in the left-right direction defined above in FIG. 4B, but the present invention is not limited to this, and the upper tab 161 described later is directed to the right. The lower tab 162 may be bent in the opposite direction to the left.

  The flowing water portion (communication portion) 122 is provided with a leeward tab (not shown) for adjusting the interval between adjacent fins 120.

  A procedure for forming the tabs 161 and 162, the louvers 181 and 182 and the hole 191 will be described below with reference to FIG. The upper part of the projecting part 150 on the windward side is formed by cutting up in a substantially rectangular shape toward the upper end of the projecting part 150 at a position about 1 mm (L1) downstream from the windward tip 150a of the projecting part 150. There is a tab 161. The upper tab 161 has a height of about 1.5 mm (H2) when it is cut and raised. Similarly, it is formed in the lower part on the windward side of the projecting part 150 by cutting it into a substantially rectangular shape toward the lower end of the projecting part 150 at a position about 1 mm (L1) downstream from the windward tip 150a of the projecting part 150. There is a lower tab 162 to be played. When the lower tab 162 is also cut and raised, the height is about 1.5 mm (H2). The upper tab 161 and the lower tab 162 are cut into three pieces other than the upper end side or the lower end side among the four sides of the rectangle, and the remaining one side 161a of the upper end side or one side 162a of the lower end side is folded. Then, it is formed by bending. The upper tab 161 and the lower tab 162 have a width of about 1.5 mm (L2) with respect to the ventilation direction. Note that the upper tab 161 and the lower tab 162 are located approximately 1 mm (L1) downstream from the windward tip 150a of the protruding portion 150 in order to adjust the spacing between the adjacent fins 120. Is as close as possible to the windward tip 150a of the projecting portion 150, and the portion 151 of the projecting portion 150 between the windward tip 150a of the projecting portion 150 and the upper tab 161 or the lower cut-and-raised portion 162 does not break. This is to ensure the width.

  A notch 163 passing through the center of each hole formed by cutting and raising the upper tab 161 and the lower tab 162 is inserted into the protruding portion 150. The length of the notch 163, that is, the length of the width in the vertical direction of the louvers 181 and 182 is about 2.5 mm (H3). A cut-and-raised piece formed by the notch 163 and one side 161a on the lower end side of the upper tab 161 or one side 162a on the upper end side of the lower tab 162 is protruded by folding the sides 181a and 182a continuous with the fin 120, respectively. Each of 150 is caused to incline in the opposite direction in the left-right direction defined above. The raised cut pieces are louvers 181 and 182, respectively. Further, the hole formed by being cut and raised becomes a part of the hole portion 191. By forming the louvers 181 and 182, a leading edge effect that a boundary layer of air is thinned at the tips of the louvers 181 and 182 to obtain a high heat transfer coefficient is produced. On the other hand, the formation of the hole 191 makes it difficult to transfer the heat transferred from the flat tube 130 to the windward tip 150a of the protruding portion. Therefore, the time until a large amount of frost adheres to the windward tip 150a of the protruding portion 150 can be delayed. The vertical length H1 of the hole 191 is about 5.5 mm, and is the total length of the height H2 of the upper tab 161, the length H3 of the louvers 181 and 182 and the height H2 of the lower tab 162. .

  As described above, according to the present invention, the upper tab 161, the lower tab 162, and the louvers 181 and 182 are formed around the hole portion 191, so that the conventional method has a short protruding portion that has no room for forming both the tab and the hole portion. 150 can form both tabs and holes.

  In this embodiment, the louvers 181 and 182 are formed in order to form a part of the hole portion 191, but the present invention is not limited to this, as shown in FIGS. In order to form a part of the hole 191, a part of the protruding part 150 may be cut out.

  In addition, although the present Example demonstrated the case where a heat exchanger tube was a flat tube, this invention is not limited to this, It uses for what is called a fin and tube type heat exchanger with which the heat exchanger tube was cylindrical shape. Also good. The numbers shown in the examples are only examples, and the present invention may be appropriately changed according to the size of the heat exchanger, and is not limited thereto.

DESCRIPTION OF SYMBOLS 100 Heat exchanger 120 Fin 130 Flat tube 153 Heat transfer part 161 Upper tab 162 Lower tab 181, 182 Louver 191 Hole

Claims (3)

A plurality of heat transfer tubes arranged vertically,
Crossing the plurality of heat transfer tubes, a plurality of plate-like fins arranged on the left and right,
A heat exchanger having a plurality of ventilation paths surrounded by the heat transfer tubes adjacent in the vertical direction and the fins adjacent in the horizontal direction;
The fin includes a heat transfer section that forms the ventilation path,
And a protruding portion protruding to the windward side than the heat transfer portion,
The protruding portion has a hole formed from the upper part to the lower part,
An upper tab extending toward an adjacent fin is formed at an upper end of the hole, and a lower tab extending toward an adjacent fin is formed at a lower end of the hole.   2. The heat exchanger according to claim 1, wherein the upper tab and the lower tab are formed by partially raising and lowering fins by folding the upper end or the lower end of the hole portion. 3. The heat exchanger according to claim 1, wherein louvers that are inclined with respect to the ventilation direction are formed at both the windward side and the leeward side of the hole.

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