HEAT EXCHANGER

A heat exchanger includes a communication flow path 31 which communicates a first lower tank provided in a plurality of laminated flat tubes with a second lower tank provided adjacent to the first lower tank, the communication flow path 31 includes a throttle portion 34 formed in the center in a width direction, the throttle portion 34 has a curved surface formed in a protruded shape inside the communication flow path 31 with a predetermined radius of curvature R, when the length, in which an outer dimension in a height direction is the maximum, of the communication flow path 31 is set to be H, and the length, in which an outer dimension in the width direction is the maximum, of the communication flow path 31 is set to be W, the radius of curvature R of the throttle portion 34 is R≧0.2 H.

FIELD

The present invention relates to a multi-flow type heat exchanger.

BACKGROUND

Conventionally, as a multi-flow type heat exchanger, a laminated heat exchanger (evaporator), in which a plurality of core bodies (flat tubes) are laminated, has been known (for example, see Patent Literature 1). In this heat exchanger, two tanks are provided on the windward side and the leeward side on the upper side, and two tanks are provided on the windward side and the leeward side on the lower side. In the heat exchanger, both ends of the core bodies in a lamination direction are closed by an end plate. On one end of the end plate, a flow path has been formed, in which the flow path communicates the tanks on the windward side and the leeward side positioned on the upper side.

CITATION LIST

Patent Literature

SUMMARY

Technical Problem

In the heat exchanger disclosed in Patent Literature 1, a refrigerant, flowing in the tank, passes through the flow path formed on the end plate from one tank on the upper side, and flows into the other tank on the upper side. At this time, pressure of the flowing refrigerant is added to a plate surface of the end plate in a direction perpendicular to the plate surface. When the pressure is added to the end plate, the end plate may be deformed. Therefore, it is desirable to enhance the rigidity of the end plate. Here, increasing the thickness of the end plate or providing a reinforcing rib on the end plate is considered to enhance the rigidity of the end plate.

However, when the thickness of the end plate is increased, the weight of the heat exchanger is increased and the cost may also be increased by the increased thickness of the end plate. In addition, when the reinforcing rib is provided on the end plate, the structure becomes complicated. As a result, a part in which stress easily is concentrated, is formed. Therefore, it is difficult to suppress deformation of the end plate, and the cost may be increased since the structure becomes complicated.

It is an object of the present invention to provide a heat exchanger capable of suppressing pressure deformation with a simple configuration.

Solution to Problem

According to an aspect of the present invention, a heat exchanger includes: a plurality of flat tubes to be laminated; a plurality of fins provided between the adjacent flat tubes; a first tank communicating with a first refrigerant flow path formed inside the flat tube, provided on one side in a longitudinal direction of the flat tube, and provided over a lamination direction of the plurality of flat tubes; a second tank communicating with a second refrigerant flow path formed inside the flat tube, provided on one side in the longitudinal direction of the flat tube, and provided over the lamination direction and adjacent to the first tank; and a communication member including a wall body which forms a communication flow path to communicate the first tank with the second tank. When a direction which is perpendicular to the lamination direction and in which the first tank and the second tank are adjacent to each other is set to be a width direction, and a direction which is perpendicular to the width direction and the lamination direction is set to be a height direction, an outer shape of the wall body of the communication flow path, seen from the lamination direction, is formed to be long in the width direction compared with in the height direction and the communication flow path includes a throttle portion formed on the center in the width direction, an outer wall surface of the wall body in the throttle portion has a curved surface formed in a protruded shape inside the communication flow path with a predetermined radius of curvature R. When the length, in which an outer dimension in the height direction is the maximum, of the communication flow path is set to be H, and the length, in which an outer dimension in the width direction is the maximum, of the communication flow path is set to be W, the radius of curvature R of the throttle portion is R≧0.2 H, the length L, in which an outer dimension in the height direction is the minimum, of the throttle portion of the communication flow path is L≦0.9 H, and a part of the length H, in which the outer dimension in the height direction is the maximum, is provided in a position in the width direction outside by ¼ W or more from a part of the communication flow path being the length L.

According to this configuration, the pressure deformation of a communication member can be suppressed, by providing a throttle portion in a communication flow path and making the shape of the communication flow path as a predetermined shape. Here, only providing the throttle portion may cause concentration of stress at the throttle portion, and the communication member may be deformed by pressure. Therefore, a radius of curvature R of the throttle portion in the communication flow path is made R≧0.2 H, so that the gradient of the throttle portion becomes gentle and the concentration of the stress can be suppressed. In addition, the length L of the throttle portion is made L≦0.9 H, so that pressure receiving area can be reduced and the rigidity can be enhanced. Moreover, a part of the length H, in which an outer dimension in a height direction is the maximum, is provided in a position in a width direction outside by ¼ W or more from a part of the length L of the throttle portion. As a result, an opening of a first tank communicating with the communication flow path and an opening of a second tank communicating with the communication flow path do not overlap. Therefore, a pressure receiving surface of the communication flow path from the first tank and a pressure receiving surface of the communication flow path from the second tank do not overlap. Therefore, pressure increase by overlapping of the pressure receiving surfaces can be suppressed.

Advantageously, in the heat exchanger, when a line, passing through the part of the length H, in which the outer dimension in the height direction is the maximum, is set to be an axis line, an outer shape of a virtual oval, which is obtained by developing the outer part in the width direction from the axis line line-symmetrically around the axis line, is formed to be short in the width direction compared with in the height direction.

According to this configuration, the outer shape of a virtual oval can be formed to be short in a width direction compared with in the height direction. Therefore, the communication flow path can be made short in the width direction and the configuration of the heat exchanger itself can be made compact.

Advantageously, in the heat exchanger, the communication flow path is 0.5<W/H<1.0.

According to this configuration, the communication flow path can be long in the width direction compared with in the height direction. Therefore, a first lower tank and a second tank can be suitably connected to the communication flow path, without overlapping the first tank and the second tank adjacent to each other in the width direction.

DESCRIPTION OF EMBODIMENTS

Hereinafter, an embodiment according to the present invention will be described in detail with reference to the drawings. The present invention is not limited to this embodiment. In addition, components in the following embodiment include a component, which may be easily replaced by those skilled in the art, or the substantially same component.

Embodiment

FIG. 1is a schematic configuration view of a heat exchanger according to the present embodiment.FIG. 2is a perspective view of surroundings of an end plate of the heat exchanger.FIG. 3is a sectional perspective view of surroundings of the end plate of the heat exchanger cut at a surface perpendicular to a width direction.FIG. 4is a partial sectional view of surroundings of the end plate of the heat exchanger cut at the surface perpendicular to the width direction.FIG. 5is a sectional view of a communication flow path cut at a surface perpendicular to a lamination direction.FIGS. 2 to 4are figures in which the vertical direction (longitudinal direction) inFIG. 1is reversed.

A heat exchanger1of the present embodiment is a multi-flow type laminated heat exchanger, and is used, for example, as an evaporator of an air conditioner mounted on an automobile. The heat exchanger1of the present embodiment can be applied to any of multi-flow type laminated heat exchangers, and is not particularly limited.

As illustrated inFIGS. 1 to 4, the heat exchanger1of the present embodiment includes a plurality of flat tubes2, a plurality of corrugated fins3(seeFIG. 4), and a pair of end plates4. The plurality of flat tubes2is laminated in the lamination direction. The plurality of corrugated fins3is provided between flat tubes2adjacent to each other in the lamination direction. The pair of the end plates4is provided at both sides in the lamination direction. Then, the plurality of laminated flat tubes2, the plurality of corrugated fins3, and the pair of end plates4are integrally joined by brazing.

The flat tube2is formed to be extended in the longitudinal direction by joining a pair of molded plates formed by press molding. The flat tube2has a flat-shaped cross-section cut at a surface perpendicular to the longitudinal direction, and is laminated in the direction perpendicular to a flat surface. A first upper opening11aand a second upper opening12aare formed through the flat tube2in the lamination direction in one end (upper end) in the longitudinal direction. A first lower opening21aand a second lower opening22aare formed through the flat tube2in the lamination direction in the other end (lower end) in the longitudinal direction. The first upper opening11aand the second upper opening12aare provided side by side in the width direction, which is perpendicular to the longitudinal direction and the lamination direction. Similarly, the first lower opening21aand the second lower opening22aare provided side by side in the width direction.

The plurality of flat tubes2is laminated in the lamination direction, so that pluralities of first upper openings11aand second upper openings12aare coupled in the lamination direction. The plurality of first upper openings11acoupled in the lamination direction functions as a first upper tank11. Similarly, the plurality of second upper openings12acoupled in the lamination direction functions as a second upper tank12. In other words, the first upper opening11aand the second upper opening12arespectively becomes a part of the first upper tank11and the second upper tank12. Therefore, each of the first upper tank11and the second upper tank12is formed to be extended in the lamination direction, at the end of one side in the longitudinal direction of the plurality of laminated flat tubes2, adjacently in parallel in the width direction. At this time, air A flowing in the heat exchanger1flows from the upstream side toward the downstream side in the width direction. Therefore, the first upper tank11is provided on the downstream side in the width direction and the second upper tank12is provided on the upstream side in the width direction.

As illustrated inFIG. 2, the plurality of flat tubes2is laminated in the lamination direction, so that pluralities of first lower openings21aand second lower openings22aare coupled in the lamination direction as with the first upper opening11aand the second upper opening12a.The plurality of first lower openings21acoupled in the lamination direction functions as a first lower tank21. Similarly, the plurality of second lower openings22acoupled in the lamination direction functions as a second lower tank22. In other words, the first lower opening21aand the second lower opening22arespectively becomes a part of the first lower tank21and the second lower tank22. Therefore, each of the first lower tank21and the second lower tank22is formed to be extended in the lamination direction, at the end of the other side in the longitudinal direction of the plurality of laminated flat tubes2, adjacently in parallel in the width direction. The first lower tank21is provided on the downstream side in the width direction and the second lower tank22is provided on the upstream side in the width direction.

Although illustration is omitted, a first refrigerant flow path and a second refrigerant flow path are formed inside the flat tube2. The first refrigerant flow path is a flow path which communicates the first upper tank11(first upper opening11a) with the first lower tank21(first lower opening21a). The second refrigerant flow path is a flow path which communicates the second upper tank12(second upper opening12a) with the second lower tank22(second lower opening22a).

As illustrated inFIG. 4, the corrugated fin3is a corrugated plate with a waveform of transverse waves toward the longitudinal direction, and mountain parts and valley parts are formed to be extended in the width direction. Thus, the air A flowing in the width direction of the heat exchanger1is cooled down by passing through the corrugated fin3.

As illustrated inFIG. 1, the pair of end plates4blocks the end in the lamination direction of the first upper tank11, the second upper tank12, the first lower tank21, and the second lower tank22, communicates the first upper tank11with the second upper tank12adjacent to each other, and communicates the first lower tank21with the second lower tank22adjacent to each other.

The end plate4is formed to be extended in the longitudinal direction by joining a pair of molded plates formed by press molding as with the flat tube2. A refrigerant inlet (Rin), from which a refrigerant flows into the heat exchanger1, and a refrigerant outlet (Rout), out of which the refrigerant flows from the heat exchanger1, are formed at one end (upper end) in the longitudinal direction at one end plate4of the pair of end plates4. The refrigerant inlet (Rin) is connected to the first upper tank11and the refrigerant outlet (Rout) is connected to the second upper tank12. In addition, a communication flow path31, which communicates the end of the first lower tank21with the end of the second lower tank22, is formed at the other end (lower end) in the longitudinal direction at the other end plate4of the pair of end plates4.

In addition, a partition part18is installed in the intermediate part in the lamination direction of the first lower tank21. Similarly, a partition part19is installed in the intermediate part in the lamination direction of the second upper tank12.

As illustrated inFIG. 1, when the refrigerant flows from outside into the heat exchanger1with the above configuration, the refrigerant flows into one end in the lamination direction of the first upper tank11through the refrigerant inlet (Rin). The refrigerant, which has flowed into one end of the first upper tank11, flows in the first refrigerant flow path in the flat tube2and flows into the first lower tank21, on one end side (right side inFIG. 1) of the heat exchanger1relative to the partition part18. Since the first lower tank21is partitioned by the partition part18, the refrigerant, which has flowed in the first lower tank21, flows in the first refrigerant flow path in the flat tube2again and flows into the first upper tank11. Then, the refrigerant, which has flowed into the first upper tank11, flows into the first upper tank11on the other end side (left inFIG. 1) of the heat exchanger1relative to the partition part18.

The refrigerant, which has flowed into the first upper tank11on the other side, flows in the first refrigerant flow path in the flat tube2and flows into the first lower tank21. The refrigerant, which has flowed into the first lower tank21, flows toward the other end (left inFIG. 1) in the lamination direction of the first lower tank21. The refrigerant, which has flowed into the other end of the first lower tank21, flows into the other end in the lamination direction of the second lower tank22through the communication flow path31.

The refrigerant, which has flowed into the other end of the second lower tank22, flows in the second refrigerant flow path in the flat tube2and flows into the second upper tank12, on the other end side of the heat exchanger1relative to the partition part19. Since the second upper tank12is partitioned by the partition part19, the refrigerant, which has flowed in second upper tank12, flows in the second refrigerant flow path in the flat tube2again, and flows into the second lower tank22. Then, the refrigerant, which has flowed into the second lower tank22, flows into the second lower tank22on one end side (right inFIG. 1) of the heat exchanger1relative to the partition part19.

The refrigerant, which has flowed into the second lower tank22on one side, flows in the second refrigerant flow path in the flat tube2and flows into the second upper tank12. The refrigerant, which has flowed into the second upper tank12, flows toward one end side (right inFIG. 1) in the lamination direction of the second upper tank12. The refrigerant, which has flowed into one end of the second upper tank12, flows outside the heat exchanger1through the refrigerant outlet (Rout).

Although in the present embodiment, the heat exchanger1has been configured in the above-described manner, the configuration is not limited to the above-described configuration. The position and the number of installation of the partition parts18and19, the position and the number of installation of the communication flow path31, and the position of the refrigerant inlet (Rin) and the refrigerant outlet (Rout) can be appropriately changed, so that the flow path, in which the refrigerant flows, is designed to be a predetermined flow path.

Next, the communication flow path31will be described with reference toFIGS. 2 to 5. As illustrated inFIG. 2, the communication flow path31provided on the end plate4(communication member) of the present embodiment is a flow path which communicates the first lower tank21with the second lower tank22. InFIGS. 2to4, the communication flow path31is illustrated to be positioned on the upper right side. Although the present embodiment is described by being applied in the communication flow path31, which communicates the first lower tank21with the second lower tank22, the flow path is not particularly limited as long as it communicates adjacent tanks.

The flow path of the communication flow path31is formed by a wall body32provided on the end plate4. As illustrated inFIG. 5, the outer shape of the wall body32of the communication flow path31is long in the width direction, when seen from the lamination direction, compared with in a height direction (longitudinal direction) perpendicular to the lamination direction and the width direction.

The outer shape of the wall body32of the communication flow path31is vertically symmetric (symmetric in the height direction) and bilaterally symmetric (symmetric in the width direction), when seen from the lamination direction. A throttle portion34is formed in the center in the width direction of this communication flow path31. An outer wall surface of the wall body32in the throttle portion34has a curved surface formed in a protruded shape inside the communication flow path31with a predetermined radius of curvature R. Therefore, as illustrated inFIG. 3, the communication flow path31is the flow path, in which the center in the width direction is narrow and both sides in the width direction are wide. The thickness of the wall body32of the communication flow path31is, for example, 0.5 mm to 1.0 mm.

Here, as illustrated inFIG. 5, the length, in which an outer dimension (dimension of the outer wall surface of the wall body32) in the height direction is the maximum, of the communication flow path31seen from the lamination direction, is set to be H. That is, the length H is the length between a pair of top parts32a,in which the outer dimension in the height direction is the maximum. At this time, since the communication flow path31is symmetric in the width direction, the pair of top parts32ain the length H is provided in each of both sides in the width direction.

In addition, the length, in which an outer dimension in the height direction is the minimum, of the communication flow path31seen from the lamination direction, is set to be L. That is, the length L is the length between a pair of valley parts32b,which is formed on the throttle portion34, in which the outer dimension in the height direction is the minimum. Here, the length L is the length which passes through the center in the width direction.

Moreover, the length, in which an outer dimension in the width direction is the maximum, of the communication flow path31seen from the lamination direction, is set to be W. That is, the length W is the length between a pair of top parts32c,in which the outer dimension in the width direction is the maximum. Specifically, the length W is W<40 mm.

Then, since the communication flow path31is long in the width direction compared with in the height direction (longitudinal direction), 0.5<H/W<1.0 is satisfied. Therefore, the first lower tank21and the second lower tank22adjacent to each other in the width direction can be suitably connected to the communication flow path31.

The communication flow path31configured in the above manner is provided with the throttle portion34in the center in the width direction, so that pressure deformation of the communication flow path31is suppressed. However, only providing the throttle portion34may cause concentration of stress at the throttle portion34.

Therefore, the shape of the communication flow path31is made as the shape described below.

In the communication flow path31, the radius of curvature R of the wall body32in the throttle portion34is R≧0.2 H. That is, in the throttle portion34, the radius of curvature R is formed to be R≧0.2 H, so that the gradient of the throttle portion34becomes gentle and the concentration of the stress can be suppressed.

In addition, in the communication flow path31, the length L of the throttle portion34in the height direction is L≦0.9 H. That is, in the throttle portion34, the length L is formed to be L≦0.9 H, so that pressure receiving area in a surface perpendicular to the lamination direction of the communication flow path31is reduced and the rigidity can be enhanced by the wall body32of the throttle portion34.

Moreover, in the communication flow path31, the top part32aof the length H is positioned in the width direction outside by more than ¼ W from the valley part32bof the length L. That is, when a line, passing through the top parts32aof the length H, is set to be an axis line I, and a shape, which is obtained by developing the outer part in the width direction from the axis line I line-symmetrically around the axis line I, is set to be a virtual oval O, the communication flow path31is shaped, so that outer diameters of virtual ovals O at both sides in the width direction do not overlap. That is, the length C of the virtual oval O in the width direction is C≦W/2. Therefore, a pressure receiving surface of the communication flow path31from the first lower tank21in the lamination direction, and a pressure receiving surface of the communication flow path31from the second lower tank22do not overlap. As a result, pressure increase caused by overlapping of the pressure receiving surfaces can be suppressed. At this time, the outer shape of the virtual oval O is short in the width direction compared with in the height direction.

As described above, according to the present embodiment, the pressure deformation of the end plate4can be suppressed, by providing the throttle portion34in the communication flow path31and making the shape of the communication flow path31as the above-described shape.

In addition, according to the configuration of the present embodiment, the outer shape of the virtual oval O can be formed to be short in the width direction compared with in the height direction. Therefore, the communication flow path31can be made short in the width direction and the configuration of the heat exchanger1itself can be made compact.

In addition, according to the present embodiment, the communication flow path31can be made long in the width direction compared with in the height direction. Therefore, the first lower tank21and the second lower tank22adjacent to each other in the width direction can be suitably connected to the communication flow path31

Although the present embodiment is applied to the communication flow path31, which communicates the first lower tank21with the second lower tank22, the present embodiment may be applied to a communication flow path, which communicates the first upper tank11with the second upper tank12.

REFERENCE SIGNS LIST