JP2012247091A - Fin and tube type heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fin and tube type heat exchanger in which a distance between adjacent fins is hardly disordered.SOLUTION: This fin and tube type heat exchanger is configured by integrally forming a collar section 18 around an assembly slit 16 on an upper face of a fin 12 in standing manner, one of regions opposed to each other through a flat porous tube in the collar section 18, is formed as a high collar region 20, and a tip section of the high collar region 20 is kept into contact with a lower face of the adjacent fin 12.

Description

  The present invention relates to a fin-and-tube heat exchanger, and more particularly to a fin-and-tube heat exchanger suitably used in an air conditioner such as a home air conditioner or an automobile air conditioner.

  Conventionally, heat exchangers that operate as evaporators or condensers have been used in refrigerators, heat pump water heaters, etc., in addition to air conditioning equipment such as home air conditioners, automotive air conditioners, and packaged air conditioners. In indoor air conditioners and commercial packaged air conditioners, fin-and-tube heat exchangers having a structure in which fins are assembled to heat transfer tubes are most commonly used.

  Such fin-and-tube heat exchangers generally have a structure in which heat transfer tubes are inserted perpendicularly to a plurality of fins (outer surface fins) and the plurality of fins and heat transfer tubes are joined. Has been. In the heat exchanger having such a structure, the refrigerant is circulated in the heat transfer tube, while air as a heat exchange fluid is caused to flow through the gaps between the plurality of fins in a direction perpendicular to the heat transfer tube. Thus, heat exchange is performed between the refrigerant and the air.

  Here, the fin which comprises such a fin and tube type heat exchanger is generally comprised from the board | plate material made from aluminum or aluminum alloy. In addition, as one of the heat transfer tubes used in the fin-and-tube heat exchanger, a flat multi-hole tube having a structure in which a flat tube interior is divided into a plurality of flow paths by a plurality of partition walls is provided. ,Are known. In this flat multi-hole tube, in general, those obtained by extrusion of a port hole from aluminum or an aluminum alloy as a material are generally used because of its ease of manufacture. As described above, since the fins and heat transfer tubes constituting the heat exchanger are all made of aluminum material, the fin-and-tube heat exchanger can be effectively reduced in size and weight. In addition, there is an advantage that the cost is lower than that of a copper material.

  In addition, as a typical method of joining the fin and the heat transfer tube in such a fin-and-tube heat exchanger, a heat transfer tube inserted into a mounting hole provided in the fin is used for mechanical expansion or hydraulic pressure. Expanding the tube by expanding the tube, etc., a method of expanding the tube so that the inner surface of the mounting hole and the outer peripheral surface of the heat transfer tube are in close contact with each other, a method called a crimping method in which the heat transfer tube is press-fitted into the mounting hole of the fin and assembled, A brazing method or the like in which the gap between the outer peripheral surface of the heat transfer tube inserted into the mounting hole and the mounting hole is filled with a brazing material is well known. Of these joining methods, in the case of a fin-and-tube heat exchanger using a flat multi-hole tube as a heat transfer tube, it is difficult to expand by a mechanical tube expansion method. Many knuckles and brazing methods are used.

  Conventionally, various fin-and-tube heat exchangers have been proposed. For example, in Japanese Patent Application Laid-Open No. 2007-155181 (Patent Document 1), a cut-and-raised portion is provided around a fitting groove provided in a flat fin, and a plurality of such fins are stacked in parallel at a constant pitch. In the fitting groove, a fin-and-tube type constructed so that the outer periphery of the cross section in which the refrigerant flows is inserted into a heat transfer tube having a flat cross section at a substantially right angle so that the fin and the heat transfer tube are closely bonded. A heat exchanger is revealed. In JP 2010-156525 A (Patent Document 2), plate-shaped fins made of an aluminum alloy are stacked at a predetermined interval, and a groove provided in the plate-shaped fin is along the longitudinal direction in the longitudinal direction. A flat heat transfer tube provided with a refrigerant flow path is inserted, the solder layer provided on the outer surface of the front edge of the heat transfer tube is melted, and the heat transfer tube is fixed to the plate fin by the solder. The exchanger is revealed.

  However, in the heat exchangers disclosed in Patent Document 1 and Patent Document 2, when the fins and the heat transfer tubes are fixed by brazing, adjacent fins are caused due to brazing defects. The distance between them may not be the desired distance. Specifically, when producing a heat exchanger in which the distance between adjacent fins is small (narrow), when brazing is performed in a state where the distance between fins is small (narrow), the heat transfer tubes and the fins are joined. The brazing material (solder) may enter not only the gap between the heat transfer tube and the fin but also between the adjacent fins and the fins may stick to each other.

  The problem that the distance between adjacent fins does not reach the desired distance is due to an external force being applied to the fins, for example, when brazing the fins and the heat transfer tubes other than those caused by the above-mentioned poor brazing. For example, the distance between adjacent fins becomes larger (or smaller) than the target distance, and the fin is fixed in such a state. And in heat exchangers where the distance between adjacent fins is disturbed, the air flow resistance of the heat exchange medium increases and the heat exchange performance of the fin-and-tube heat exchanger decreases. It caused a problem of letting go.

  On the other hand, various types of fin-and-tube heat exchangers have been proposed as conventional fin-and-tube heat exchangers in which disturbance of the distance between adjacent fins hardly occurs.

  Specifically, in Japanese Patent Laid-Open No. 10-78296 (Patent Document 3), the relationship between the thickness (H) of the flat heat exchange tube (heat transfer tube) and the pitch (P) of the plate fins is expressed as P <H <2 × P, the length (L) of the upright piece cut and raised from the opposing long side of the opening edge of the insertion hole is at least equal to or greater than the pitch (P) of the plate fin, and the upright piece is flattened A heat exchanger has been proposed in which it is brought into uniform contact with the heat exchanger tube.

  In JP-A-2005-127595 (Patent Document 4), a through hole for inserting and closely bonding a heat transfer tube having a flat cross-sectional outer periphery to the fin is provided in a shape substantially along the cross-sectional outer periphery. There has been proposed a heat exchanger in which a fin collar is provided in a part of the periphery of the through hole to maintain a constant interval between the fins to be stacked.

  Furthermore, in Japanese Patent Application Laid-Open No. 2007-24426 (Patent Document 5), a heat exchanger is proposed in which a fin is provided with a cut and raised spacer that is higher than the height of the fitting collar on the fin. Has been.

  However, in the heat exchanger proposed in Patent Document 3, the thickness of the flat heat exchange tube (heat transfer tube) and the fin pitch (distance between adjacent fins) must satisfy a predetermined relationship. Therefore, it was impossible to make the fin pitch (distance between adjacent fins) greater than the thickness of the heat transfer tube. Moreover, since the heat exchanger proposed in Patent Document 4 is formed by inserting heat transfer tubes in the direction perpendicular to the fin surfaces, it is difficult to insert the heat transfer tubes only by slightly shifting the relative positions of the plurality of fins. There is a problem of becoming. Furthermore, in the heat exchanger disclosed in Patent Document 5, since a cut and raised spacer is provided separately from the fitting collar, a step of providing such a cut and raised spacer is required separately. There is a problem that an increase in manufacturing cost is inevitable.

JP 2007-155181 A JP 2010-156525 A JP-A-10-78296 JP 2005-127595 A JP 2007-24426 A

  Here, the present invention has been made in the background of such circumstances, and the problem to be solved is that between fins adjacent to each other in a fin-and-tube heat exchanger of an air conditioner. It is an object of the present invention to provide a fin-and-tube heat exchanger that is less likely to be disturbed.

  In the present invention, in order to solve such a problem, in a large number of plate-like fins made of aluminum or an alloy thereof stacked and spaced apart from each other by a predetermined distance, the corresponding peripheral edge portions are used. Fin-and-tube heat exchangers that are assembled by fitting flat multi-hole tubes made of aluminum or its alloys into the assembly slits in the shape of side openings that are provided so as to open. The collar portion is erected integrally around the assembly slit on the upper surface of the fin, and one of the opposing portions of the collar portion facing the flat multi-hole tube is higher than the other. On the other hand, the distance between the adjacent fins is controlled by making the tip of the high color portion abut the lower surface of the adjacent fin. The fin-and-tube heat exchanger, characterized in that so as to be, is to its gist.

  In such a fin-and-tube heat exchanger according to the present invention, it is preferable that at least a part of the other portion of the collar portion facing the high collar portion is inclined inward. The inclined collar portion is configured to be brought into contact with the surface of the flat multi-hole tube at the tip side portion of the inclined collar portion.

  In the fin-and-tube heat exchanger of the present invention, more preferably, the assembly slit is formed in a U shape.

  As described above, in the fin-and-tube heat exchanger according to the present invention, the collar portion is integrally provided around the assembly slit on the upper surface of the fin, and the flat portion of the collar portion is provided. One of the parts facing each other with the hole tube in between is made a high collar part having a part higher in height than the other, while the tip part of the high color part is placed on the lower surface of the adjacent fin (the collar part stands upright). The distance between adjacent fins is defined by abutting on the non-contact side surface). By adopting such a configuration, even when an unexpected external force is applied to the fins when brazing the fins and the flat multi-hole tube, the distance between adjacent fins is sufficient. As a result, the distance between adjacent fins is less likely to be disturbed.

  In addition, the other part of the collar part that faces the above-described high collar part is preferably at least partially inclined inward to form an inclined collar part, and the tip side of the inclined collar part It is made to contact | abut on the surface of a flat multi-hole pipe | tube in a site | part. By adopting such a configuration, the inclined collar portion elastically comes into contact with the surface of the flat multi-hole tube, so that the joint between the fin and the flat multi-hole tube is more firmly secured. It becomes.

It is a perspective explanatory view showing an example of a fin and tube type heat exchanger according to the present invention. It is a perspective explanatory view which shows the fin which comprises the fin and tube type heat exchanger shown by FIG. FIG. 3 is an explanatory cross-sectional view showing an enlargement of an assembly slit portion of the fin shown in FIG. 2. It is a perspective explanatory drawing which expands and shows the junction part of the fin of the fin and tube type heat exchanger according to this invention, and a flat multi-hole tube. It is an isometric view explanatory drawing which shows another example of the fin which comprises the fin and tube type heat exchanger according to this invention. FIG. 6 is an enlarged cross-sectional explanatory view showing an assembly slit portion of the fin shown in FIG. 5. It is sectional explanatory drawing which expands and shows an assembly | attachment slit part about another example of the fin which comprises the fin and tube type heat exchanger according to this invention.

  Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.

  First, FIG. 1 schematically shows one embodiment of a fin-and-tube heat exchanger according to the present invention in a perspective view. In this case, the heat exchanger 10 is a slit in which one flat multi-hole tube 14 is provided in the fin 12 with respect to the plurality of fins 12 stacked and arranged in parallel with each other at a predetermined distance. After being inserted into the shaped assembly slit 16, it is formed by being fixed by brazing.

  More specifically, the fin 12 is formed of a metal material made of aluminum or an aluminum alloy, as in the prior art, and has a rectangular plate shape as shown in FIG. It is said to be a fin. An assembly slit 16 into which the flat multi-hole tube 14 is assembled is provided at a substantially central portion of the fin 12 and extends from the end of one side of the rectangular fin 12 toward the opposite side. It is formed as a slit. Further, a collar portion 18 is integrally formed upright from the fins 12 around the assembly slit 16. The thickness (t) of the fin 12 is appropriately determined according to the size of the flat multi-hole tube 14 to be assembled, the required performance of the heat exchanger 10, and the like. Is 0.080 mm or more and 0.120 mm or less.

  As shown in FIGS. 2 and 3, the collar portion 18 formed integrally with the peripheral portion of the assembly slit 16 is one of the portions facing each other with the flat multi-hole tube 14 in between ( In FIG. 3, a portion on the right half side of the collar portion 18 is a high color portion 20 having a portion that is higher than the other portion (low color portion 22). More specifically, the high collar portion 20 is a lower portion (collar) of the fin 12 adjacent to the tip portion of the U-shaped assembly slit 16 erected from the straight portion (right straight portion in FIG. 3). It has the same height: h as the distance (design value) between adjacent fins in the heat exchanger 10 so as to abut the surface of the portion 18 that is not erected. Further, the portion that stands up from the curved portion of the U-shaped assembly slit 16 that is continuous with the portion having the height: h is configured such that the height gradually decreases, and the collar portion 18 is connected to the other portion (low color portion 22) facing each other with the flat multi-hole tube 14 in between.

  As described above, in the collar portion 18, one of the portions facing each other with the flat multi-hole tube 14 in between is the high collar portion 20, and the maximum height h of the high collar portion 20 is the target heat exchanger. 10 is the same as the distance (design value) between adjacent fins. The pair of the fin 12 and the flat multi-hole tube 14 is so arranged that the tip of the high collar portion 20 abuts on the surface on the lower surface (surface on which the collar portion 18 is not erected) of the adjacent fin 12. In the heat exchanger 10 manufactured by performing brazing and brazing the fin 12 and the flat multi-hole tube 14 in such a state, when an unexpected external force is applied to the fin during brazing, etc. Even so, the distance between adjacent fins is sufficiently secured, and the occurrence of disturbance in the distance between the fins is effectively suppressed.

  Here, the maximum height: h of the high color portion 20 is generally about 1.2 to 3.0 mm. If the maximum height of the high color portion 20 is too low, the effect of preventing the disturbance of the inter-fin distance may be reduced. If the maximum height of the high color portion 20 is too high, the ironing process described later is performed. This is because, for example, the thickness of the high color portion 20 becomes thin and is easily deformed, so that it is difficult to suppress the occurrence of disturbance in the inter-fin distance.

  By the way, the fin 12 having such a collar portion 18 (the high color portion 20 and the low color portion 22) can be advantageously obtained by, for example, the following known processing method. That is, first, an aluminum plate made of predetermined aluminum or aluminum alloy is pressed to obtain the outer shape of the fin 12, and further, the assembly slit 16 corresponding to the outer surface shape of the flat multi-hole tube 14 and its assembly A material in which a collar forming portion standing at a predetermined height from the peripheral edge portion of the assembly slit 16 is integrally formed by cutting and raising the material of the attachment slit portion is prepared. After that, by applying ironing to one of the portions facing the flat multi-hole tube (14) to be assembled in the future in the collar forming portion, the collar portion 18 Is formed.

The ironing process for forming the high color portion 20 is performed once so that the maximum height h of the high color portion 20 that is finally given: h is equal to the distance (design value) between adjacent fins. Or it is carried out several times. One ironing process is preferably performed at an ironing rate of 50% or less. The ironing rate is calculated from the following equation.
[Steeling rate (%)] = {(BA) / B} × 100 (%) (formula)
However, A is the thickness of the collar part after ironing, and B is the thickness of the collar part before ironing.

  On the other hand, the flat multi-hole tube 14 is formed by using a metal material made of aluminum or an aluminum alloy and applying a known processing method such as a port hole extrusion process to the metal material. In addition, in FIG. 1, it is set as the multi-hole pipe which exhibits the flat shape by which the seven holes 24 extended in a pipe-axis direction are formed. Further, the thickness t ′ of the flat multi-hole tube 14 is generally set to about 1.0 to 4.0 mm.

  Then, using such a flat multi-hole tube 14 and fins 12, a plurality of such fins 12 are arranged in parallel with each other in a state where the assembly slits 16 formed on each of them are aligned with each other, and the collar portion 18 are arranged so that the tips of the high collar portions 20 are in contact with the lower surface of the adjacent fin 12 (the surface on the side where the collar portion 18 is not erected). After fitting the hole tubes 14 and assembling them, the target fin-and-tube heat exchanger 10 is manufactured by brazing by a method such as placing. Although not shown here, predetermined headers are respectively connected to both ends of the flat multi-hole tube 14, and seven holes 24 of the flat multi-hole tube 14, that is, a refrigerant extending in the tube axis direction, Seven flow paths to be circulated are combined on the refrigerant inlet side and the outlet side, respectively, to constitute a fin-and-tube heat exchanger 10.

  According to the fin-and-tube heat exchanger 10 configured in accordance with the present invention as described above, the tip of the high collar portion 20 in the collar portion 18 is placed on the lower surface of the adjacent fin 12 (the collar portion 18 stands upright). When the fin 12 and the flat multi-hole tube 14 are brazed, the fin 12 Even when an unexpected external force is applied, the distance between the fins 12 is sufficiently secured, and the occurrence of the disturbance in the distance between the fins is effectively suppressed.

  As described above, one of the representative embodiments of the present invention has been described in detail. However, this is merely an example, and the present invention is not limited in any way by the specific description according to such an embodiment. It should be understood that this is not to be construed as a matter of course.

  For example, instead of the fin 12 having the collar portion 18 composed of the high collar portion 20 and the low collar portion 22 as shown in FIGS. 2 and 3, the fin 26 shown in FIGS. It can also be employed in the heat exchanger of the present invention. Here, the collar portion 28 of the fin 26 shown in FIGS. 5 and 6 includes a high collar portion 30 similar to the high collar portion 20 shown in FIGS. 2 and 3, and a gap between the high collar portion 30 and the flat multi-hole tube. And an inclined collar portion 32 facing each other. The inclined collar portion 32 is formed such that a portion standing from the straight portion of the U-shaped mounting slit 34 (the straight portion on the left side in FIG. 6) faces the opening inward (towards the tip). It is tilted at a predetermined angle: θ so that the distance from the color part 30 becomes gradually smaller. When such a fin 26 is used, the inclined collar portion 32 is elastically brought into contact with the surface of the flat multi-hole tube, so that the bonding between the fin 26 and the flat multi-hole tube can be secured more firmly. Become. Further, since the inclined collar portion 32 is elastically in contact with the surface of the flat multi-hole tube, the amount of brazing material necessary for brazing the fins 26 and the flat multi-hole tube is advantageously reduced. It is also possible to enjoy the effect of being able to. Furthermore, by reducing the amount of brazing material used, when fins 26 and flat multi-hole pipes are brazed, fins due to poor brazing, such as adjacent fins sticking together and the distance between the fins is disturbed. The occurrence of disturbance in the distance can also be advantageously avoided or eliminated. The inclination angle θ at the inclined portion of the inclined collar portion 32 is preferably 5 ° or more and 20 ° or less. By adopting an inclination angle within such a range, it is possible to ensure good spring characteristics and to effectively make the inclined collar portion 32 elastically contact the flat multi-hole tube. .

  Further, as shown in a partial cross-sectional view in FIG. 7, the fin 42 having the collar portion 40 including the inclined collar portion 36 in which the thickness of the inclined portion gradually decreases toward the distal end side and the high collar portion 38. Can also be employed in the heat exchanger of the present invention. By using the fins 42 as shown in FIG. 7, the inclined collar portion 36 is more elastically brought into contact with the flat multi-hole tube, and the joining of the fins 42 and the flat multi-hole tube is further ensured. I can do it.

  Furthermore, in the above-described embodiment, the U-shaped assembling slit 16 is exemplified as the side opening void-shaped assembling slit. However, in addition to such a shape, for example, a U-shaped It is also possible to adopt an assembling slit shape having a shape corresponding to the thickness or outer surface shape of the flat multi-hole tube 14 to be assembled, such as a V shape or a V shape.

  Furthermore, as a method for brazing the fins 12 and the flat multi-hole tube 14, a brazing method by placing brazing was illustrated, but in addition to such a method, for example, a brazing material is previously provided on the surface of an aluminum plate. Various known brazing methods such as forming fins 12 using brazed sheets, so-called brazing sheets, and brazing the fins 12 and the flat multi-hole pipes 14 can be employed. In any brazing method, the effects of the present invention are advantageously exhibited.

  In addition, although not listed one by one, the present invention is implemented in a mode to which various changes, modifications, improvements and the like are added based on the knowledge of those skilled in the art. It goes without saying that any one of them falls within the scope of the present invention without departing from the spirit of the invention.

DESCRIPTION OF SYMBOLS 10 Heat exchanger 12 Fin 14 Flat multi-hole tube 16 Assembling slit 18 Collar part 20 High color part 22 Low color part 24 Hole

Claims (3)

Assembling slits in the shape of side openings are provided in a large number of plate-like fins made of aluminum or an alloy thereof laminated at a predetermined distance from each other so as to open at their corresponding peripheral edges. On the other hand, a flat multi-hole tube made of aluminum or an alloy thereof is fitted into a fin-and-tube heat exchanger assembled,
The collar portion is erected integrally around the assembly slit on the upper surface of the fin, and one of the opposing portions of the collar portion facing the flat multi-hole tube is higher than the other portion. A fin-and-and-finger characterized in that the distance between adjacent fins is defined by bringing the tip of the high-collar part into contact with the lower surface of the adjacent fin.・ Tube type heat exchanger.   At least a part of the other portion of the collar portion facing the high color portion is inclined inward to be an inclined collar portion, and the flat multi-hole tube is formed at the tip side portion of the inclined collar portion. The fin-and-tube heat exchanger according to claim 1, wherein the fin-and-tube heat exchanger is adapted to be brought into contact with a surface. The fin-and-tube heat exchanger according to claim 1 or 2, wherein the assembly slit is formed in a U shape.

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