JP2003083695A - Heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a heat exchanger, in which even if there are small variations in the sizes of end plates 9, 10 and in folding of the plate, the height of an part 11 bent inside is held in a predetermined height, and brazing strength of the end plates 9, 10 to flat tubes 2 is enhanced. SOLUTION: The part 11 is formed by bending inside from the longitudinal direction of the end plates 9, 10 to the side of the flat tube 2. An externally bent part 12 is formed by bending outside in the end of the bent part 11 along the tube 2. The bent part 12 is brazed firmly to the tube 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger such as a condenser and an evaporator of a vehicle air conditioner.

[0002]

2. Description of the Related Art Generally, a heat exchanger has a structure in which flat tubes and corrugated fins are laminated, and both ends of the flat tubes are inserted and fixed in a header tank. This type of heat exchanger is provided with an end plate for holding the fin at the outermost end, but this end plate is simply made of a thin iron plate and is brazed to the fin at the outermost end. .

However, in the above structure, another structure is known because the strength of the end plate is insufficient.
For example, structures in which the end portions of the end plates are inserted and fixed in a header tank are known as disclosed in JP-A-11-083373 and JP-A-10-332293. In the heat exchanger disclosed in Japanese Unexamined Patent Publication No. 11-083373, as shown in FIGS. 13 and 14, both end portions of the end plates 109 and 110 have header tanks 104 and 1, respectively.
05 is inserted and fixed in the end plate 1
In order to allow the ends of 09 and 110 to be inserted and fixed without rattling, the end plates 109 and 110 are provided with a taper with a reduced thickness dimension at the tip. In such a heat exchanger 101, the end plates 109, 11 are provided at the tips of the header tanks 104, 105.
Since 0 is inserted, a space K that does not contribute to the flow path of the refrigerant is formed at the tips of the header tanks 104 and 105, which results in meaningless enlargement of the heat exchanger 101.

Also, as shown in FIG. 15 of Japanese Patent Application Laid-Open No. 11-325783, a structure is known in which both ends of an end plate 209 are bent inward.
In this publication, if the length of the inner bent portions 211 at both ends of the end plate 209 is shorter than the height of the fins 203, a force that presses the end plate 209 inward during temporary assembly acts, and therefore, FIG. As indicated by the imaginary line, the fin 203 may be pushed inward and tilted, causing deformation such as the fin 203 falling down. Therefore, as shown in FIG. 17, it is stated that the height of the inner bent portion 211 of the end plate 209 is set to be substantially the same as the height of the fin 203. In this case, since the tip end portion of the inner bent portion 211 contacts the flat tube 202, it is possible to prevent the end plate 209 from being pushed inward and the fin 203 to fall down during the temporary assembly.

[0005]

However, when molding the end plate 209, there is some variation in the length dimension of the end plate 209 itself. Therefore, when the end plate 209 is bent with the center as a reference, variations in the length dimension of the end plate 209 itself appear as variations in the length of the inner bent portion 211. In addition, when the one end of the inner bent portion 211 of the end plate 209 is used as a reference, the result is that the dimension of the inner bent portion of the other end portion varies as it is. As a result, when the length of the inner bent portion 211 of the end plate 209 is shorter than the height of the fin 203, the inner bent portion 211 of the end plate 209 comes to float from the flat tube 202 and the flat tube 2
02 will result in defective brazing. On the other hand, when the length is long, the tip of the inner bent portion 211 is embedded in the flat tube 202 during assembly, which deforms the flat tube 202, and in the worst case, the flat tube 20.
2 will be damaged.

In order to solve the above-mentioned problems of the prior art, the present invention can maintain the height of the inner bent portion at a predetermined height even if there is a slight variation in the size of the end plate or a variation during bending. It is an object of the present invention to provide a structure capable of strengthening the brazing strength between the end plate and the flat tube.

[0007]

According to a first aspect of the present invention, a heat exchanger is constructed by alternately laminating corrugated fins and flat tubes, and attaching an end plate to the outer end of the corrugated fins at the outer end in the laminating direction. In the above, the end plate includes an inwardly bent portion provided by bending inward from a longitudinal end portion of the end plate toward the flat tube, and a tip portion of the inwardly bent portion is provided with the flat tube. The external bending portion is provided so as to be bent outward so that the external bending portion is brazed and fixed to the flat tube, and the height of the internal bending portion of the end plate is accurately adjusted. Since it can be molded well, it is possible to prevent fin deformation and flat tube deformation during assembly, and it is possible to firmly bond the end plate to the flat tube.

According to the second aspect of the present invention, the end plate is provided with a rib in the longitudinal direction to increase the rigidity of the end plate, so that the function of preventing the deformation and crushing of the fins can be improved.

According to another aspect of the present invention, a header tank is arranged at the longitudinal ends of the corrugated fins and the flat tubes, and the longitudinal ends of the flat tubes are inserted at the sides of the header tank. At the open end of the header tank, a pin for vehicle mounting is integrally provided, so that the step between the header tank and the end plate can be eliminated, and when the heat exchanger is mounted on the vehicle body, air flow It is possible to reduce the blow-by of air as much as possible.

According to a fourth aspect of the present invention, the length of the outer bent portion is 5 to 10 mm, and it is possible to prevent the end plate from slipping into the flat tube even when the end plate is sandwiched during temporary assembly. The brazing of the end plate and the flat tube can be strengthened. Moreover, it is possible to reduce the blowout of air and wind from the gap between the header tank and the end plate as much as possible.

According to a fifth aspect of the present invention, in the end plate, protrusions protruding in the fin direction are provided substantially at the center in the width direction at both ends in the longitudinal direction of the portions located outside the fins. The fins can be reliably supported by the end plate during temporary assembly, and it has an excellent function of preventing fin displacement and fin drop.

According to a sixth aspect of the present invention, the outer bent portion of the end plate is inclined 5 to 20 ° with respect to the flat tube, and when the corrugated fin height varies,
Even if the corrugated fin height is high, good brazing properties can be obtained, and even if the corrugated fin height is low, damage to the flat tube can be prevented.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings. Stacked heat exchanger 1 of this embodiment
Is a condenser of an air conditioner, which is arranged at the front of the vehicle body and attached to the vehicle body frame as shown in FIG. As shown in FIG. 2, the heat exchanger 1 includes a plurality of flat tubes 2 and heat-dissipating corrugated fins 3 that are vertically stacked, and header tanks 4 and 5 are provided at both ends of the flat tubes 2. It is brazed. A partition plate 6 is provided on the header tanks 4 and 5, a refrigerant inlet portion 7 is provided at an upper end portion of the header tank 4, and an outlet portion 8 is provided at a lower end portion of the header tank 5, so that the refrigerant flows therethrough. . End plates 9 and 10 are provided outside the upper and lower outermost corrugated fins 3, respectively.

As shown in FIGS. 3 and 4, the end plate 9 (10) is made of a long plate member made of aluminum, and is formed by bending both ends in the longitudinal direction toward the flat tube 2 side. The bent portion 11 is provided. An outer bent portion 12 is provided at the tip of the inner bent portion 11 so as to be bent outward along the flat tube 2.

The end plate 9 (10) is bent inward at a position of a predetermined dimension (corresponding to the length of the corrugated fin 3) from the center portion in the longitudinal direction as a reference to form the inner bent portion 11. The length of the inner bent portion 11 is formed to be substantially equal to the height of the outermost corrugated fin 3. Then, the tip end side is further bent outward in the longitudinal direction of the end plate 9 (10) to form the outer bent portion 12. The outer bent portion 12 is formed to extend along the flat tube 2, and the inner surface of the outer bent portion 12 is in surface contact with the outer surface of the flat tube. When the end plates 9 and 10 are dimensioned, even if the end plates 9 and 10 have variations in size, the variations are absorbed as variations in the length dimension of the outer bent portion 12.

Next, the assembled state will be described. The flat tubes 2 and the corrugated fins 3 are alternately laminated, and the front and rear ends (both ends in the longitudinal direction) of the flat tubes 2 are inserted into communication holes (not shown) opened in the side portions of the header tanks 4 and 5,
The end plates 9 and 10 are set outside the outermost corrugated fins 3. Then, the end plates 9 and 10 are sandwiched by using a jig and held so that the corrugated fins 3 and the flat tubes 2 do not fall. By this holding, for the flat tube 2 and the corrugated fins 3,
Although a compressive force acts, the length of the inwardly bent portion 11 of the end plates 9 and 10 is set to be substantially the same as the height of the corrugated fins 3, so that the corrugated fins 3 can be prevented from tilting or collapsing. In particular, by providing the outer bent portion 12, it is possible to prevent the flat tube 2 from being damaged even when the end plates 9 and 10 are clamped and a compressive force is applied.

In particular, the length of the outer bent portion 12 is preferably 5 to 10 mm. The reason for this is that when the end plates 9 and 10 are clamped by a jig (not shown) during temporary assembly, the inward bent portion 11 is not affected even if an inward force is applied.
Has a length necessary to prevent the flat tube 2 from being damaged at the tip of the, and the space between the inward bent portion 11 and the header tanks 4 and 5 is made as narrow as possible to reduce air leakage in this space. This is because.

FIGS. 5 and 6 relate to the second embodiment and show views similar to those of FIGS. 3 and 4 of the first embodiment. In the second embodiment, the same parts as those in the first embodiment have the same reference numerals, and the description thereof will be omitted. Only different parts in the second embodiment are designated by different reference numerals, and this point will be described. The difference from the first embodiment is that in the second embodiment, a rib 13 is provided in the longitudinal direction on one side portion in the width direction of the end plate 9 (10) of the first embodiment.

By providing the ribs 13, the rigidity of the end plate 9 (10) can be improved and the end plate 9 (10) can be improved.
The deformation of (10) and the deformation of the corrugated fins 3 are prevented. The ribs 13 are formed on the end plate 9 (1
Although it is provided on one side of 0), it may be provided on the other side.

FIG. 7 relates to the third embodiment and shows another structure of the end plate 9 (10). This end plate 20
On both ends in the longitudinal direction of each of the protrusions, protrusions 14 directed toward the fin direction (inward direction) are provided at substantially central portions in the width direction of the outer surface portion 20a. The protrusion 14 is formed such that the protrusion height is highest at both ends in the width direction of the outer surface portion 20a. Therefore, even when the corrugated fins 3 are temporarily assembled so that the central portion of the corrugated fins 3 is outwardly convex with respect to the portions close to the header tanks 4 and 5, the protrusion height gradually increases in the end direction. Since both ends in the longitudinal direction of the corrugated fin 3 can be held by the projections 14 formed so as to have a high height, it is possible to prevent the fin 3 from slipping or coming off.

8 and 9 relate to the fourth embodiment, and
Shows a view similar to FIG. 2 of the first embodiment. FIG. 9 shows a partial view. The difference of the fourth embodiment from the first embodiment is that the caps at the lower end portions of the header tanks 4 and 5 are integrally provided with vehicle mounting pins. Since the pin 15 is provided integrally with the cap, the number of parts is reduced as compared with the case where the pin is provided on the heat exchanger with a bracket or the like.
The weight can be reduced and the cost can be reduced. Further, since the gap S between the frame F of the vehicle body and this heat exchanger can be reduced as much as possible, it is possible to greatly reduce the escape of air from this gap.

10 to 12 relate to the fifth embodiment and show another structure of the end plates 9 and 10. The outer bent portions 12 of the end plates 9 and 10 are inclined, and even if the corrugated fin height varies with respect to the design dimension, this variation is absorbed. That is, as shown in FIG. 11, even when the height of the corrugated fin is high, the brazing material A is filled in the gap between the inclined outer bent portion 12 and the flat tube 2, so that good brazing property can be secured. . Further, as shown in FIG. 12, even when the height of the corrugated fin is low, the gap between the inclined outer bent portion 12 and the flat tube 2 is reduced or almost eliminated, and damage to the flat tube 2 can be prevented. At the same time, good brazing property can be secured. As shown in FIG. 10, the outer bent portion 12 is inclined 5 to 20 ° with respect to the extending direction of the fin 3.

Even when the inner bent portion and the outer bent portion are provided on one of the end plates, the deformation of the fins 3 of the heat exchanger and the deformation of the flat tube 2 can be prevented more than before.
Although the assemblability can be improved, it is preferable to provide both.

【The invention's effect】

According to the present invention, the end plate is provided with an inwardly bent portion which is bent inward from the end in the longitudinal direction toward the flat tube, and the tip of the inwardly bent portion extends along the flat tube. Since the outer bent portion is bent outward and is provided on the flat tube by brazing, the height of the inner bent portion of the end plate can be accurately formed, and Fin deformation and flat tube deformation can be prevented, and the end plate can be firmly joined to the flat tube.

Further, in the case where a rib extending in the longitudinal direction of the end plate is provided to increase the rigidity of the end plate,
The function of preventing deformation / crush of the fins can be greatly improved.

If the pin for vehicle mounting is integrally provided at the opening end of the header tank, the step between the header tank and the end plate can be eliminated, and when the heat exchanger is mounted on the vehicle body Wind blow through can be reduced as much as possible.

[Brief description of drawings]

FIG. 1 shows a relationship between a heat exchanger to which the present invention is applied and a vehicle body.

FIG. 2 shows a heat exchanger of a first embodiment to which the present invention is applied.

FIG. 3 shows a partially enlarged view of the heat exchanger of FIG.

4 shows a partially enlarged perspective view of the heat exchanger of FIG.

FIG. 5 is a view similar to FIG. 3 relating to the second embodiment.

FIG. 6 is a view similar to FIG. 4 relating to the second embodiment.

FIG. 7 is a perspective view of an end plate according to the third embodiment.

FIG. 8 shows a heat exchanger according to a fourth embodiment.

FIG. 9 shows a partially enlarged view of FIG.

FIG. 10 is a partial enlarged view of the end plate according to the fourth embodiment.

11 shows a state in which the corrugated fin height is higher than a predetermined height in the fourth embodiment of FIG.

FIG. 12 shows a state in which the corrugated fin height is lower than a predetermined height in the fourth embodiment of FIG.

FIG. 13 shows a conventional heat exchanger.

FIG. 14 shows a partially enlarged view of FIG.

FIG. 15 shows another conventional heat exchanger.

16 is a diagram illustrating a case where the length of the inner bent portion of the end plate in the heat exchanger of FIG. 15 is shorter than the corrugated fin height.

FIG. 17 is a diagram illustrating a case where the length of the inner bent portion of the end plate and the corrugated fin height in the heat exchanger of FIG. 15 are substantially the same.

[Explanation of symbols]

1 heat exchanger 2 Flat tube 3 corrugated fins 4, 5 header tank 6 partition boards 7 entrance 8 Exit 9,10 End plate 11 Internal bend 12 External bend 13 ribs 14 Protrusion 15 pin

Claims (6)

[Claims] 1. A heat exchanger in which corrugated fins and flat tubes are alternately laminated, and an end plate is attached to the outer end of the corrugated fin at the outer end in the stacking direction, wherein the end plate is An inner bent portion provided by bending inward from the end in the longitudinal direction toward the flat tube, and an outer bent provided at the tip of the inner bent portion by bending outward along the flat tube. A heat exchanger comprising a bent portion, wherein the outer bent portion is brazed and fixed to the flat tube. 2. The heat exchanger according to claim 1, wherein the end plate is provided with ribs in the longitudinal direction. 3. A header tank is disposed at the longitudinal ends of the corrugated fins and the flat tubes, and the longitudinal ends of the flat tubes are inserted into the side portions of the header tank, and the open ends of the header tank are provided. The heat exchanger according to claim 1 or 2, wherein the vehicle is integrally provided with a pin for mounting on a vehicle. 4. The heat exchanger according to claim 1, wherein the outer bent portion has a length of 5 to 10 millimeters. 5. The end plate is provided with a protrusion protruding in the fin direction substantially at the center in the width direction at both ends in the longitudinal direction of a portion located outside the fin. The heat exchanger according to any one of 4 above. 6. The heat exchanger according to claim 1, wherein the outer bent portion of the end plate is inclined 5 to 20 ° with respect to the flat tube.