JP6102641B2 - Stacked cooler - Google Patents

Description

  The present invention relates to a stacked cooler.

  Power conversion devices such as DC-DC converters are used in hybrid cars and electric vehicles. The power conversion device includes a semiconductor module including a semiconductor element such as a switching element, and a cooler having a heat exchange unit for cooling the semiconductor module. As a cooler used for a power converter, there is a thing indicated by patent documents 1, for example.

  Patent Document 1 discloses a power conversion device including a cooler having a heat exchanging unit configured by a plurality of cooling pipes. In the heat exchanging section, a plurality of semiconductor modules and a plurality of cooling pipes are alternately stacked, and are configured to be capable of cooling by exchanging heat with a refrigerant flowing in a refrigerant flow path formed in the cooling pipe.

JP 2011-228580 A

However, the cooler disclosed in Patent Document 1 has the following problems.
In power converters, there is a demand for miniaturization, and also in a cooler, miniaturization of a heat exchange part that occupies most of the volume is required. In order to reduce the size of the heat exchange unit, a front end cooling pipe disposed at one end in the stacking direction of the heat exchange unit, a refrigerant introduction pipe and a refrigerant discharge pipe that are connected to the front end cooling pipe and allow the refrigerant to flow through the refrigerant flow path. It is necessary to reduce the diameter of the connection part. In this case, when an external force is applied to the refrigerant introduction pipe and the refrigerant discharge pipe, stress tends to concentrate on the connection portion. Therefore, the stress in the front end cooling pipe is increased and deformation is likely to occur.

  The present invention has been made in view of such a background, and intends to provide a stacked cooler that can be downsized while suppressing deformation when an external force is applied to the refrigerant introduction pipe and the refrigerant discharge pipe. It is.

In one embodiment of the present invention, a plurality of cooling pipes having a refrigerant flow path for circulating a refrigerant are connected to each other, and an arrangement gap for arranging a heat-generating component is formed between the two cooling pipes. A heat exchanging part arranged side by side,
A refrigerant introduction pipe for introducing the refrigerant into the refrigerant flow path;
A refrigerant discharge pipe for discharging the refrigerant from the refrigerant flow path,
The refrigerant introduction pipe and the refrigerant discharge pipe extend in the arrangement direction from a front end cooling pipe arranged at a front end which is one end in the arrangement direction of the plurality of cooling pipes among the plurality of cooling pipes,
Comprising rigidity improving means for improving the rigidity of the front end cooling pipe,
The front end cooling pipe is disposed on the front side and the front outer shell plate, and on the rear side, and is joined to the front outer shell plate to form the refrigerant flow path between the front outer shell plate and the front outer shell plate. A rear shell plate that forms a gap,
The refrigerant introduction pipe and the refrigerant discharge pipe are joined to the front outer shell plate,
As the rigidity improving means, at least, the thickness of the front outer shell plate is made larger than the thickness of the rear outer shell plate, and a reinforcing plate superimposed on the front end cooling pipe is provided,
The reinforcing plate has a joint portion joined around a connection portion between the refrigerant introduction pipe and the refrigerant discharge pipe in the front end cooling pipe,
In the stacked cooler, the thickness of the reinforcing plate is larger than the thickness of the front outer shell plate .

  The stacked cooler includes a rigidity improving means for improving the rigidity of the front end cooling pipe. Therefore, it is possible to prevent the front end cooling pipe from being deformed when an external force is applied to the refrigerant introduction pipe and the refrigerant discharge pipe. This prevents deformation of the front end cooling pipe even when the diameter of the connecting portion of the refrigerant introduction pipe and the refrigerant discharge pipe with the front end cooling pipe is reduced in order to reduce the size of the heat exchange section. Can do. Accordingly, the stacked cooler can be reduced in size while suppressing deformation when an external force is applied to the refrigerant introduction pipe and the refrigerant discharge pipe.

  As described above, the stacked cooler can be downsized while suppressing deformation when an external force is applied to the refrigerant introduction pipe and the refrigerant discharge pipe.

BRIEF DESCRIPTION OF THE DRAWINGS Explanatory drawing which shows the power converter device which has a laminated | stacked cooler in Example 1. FIG. II-II arrow sectional drawing in FIG. FIG. 3 is a partial cross-sectional view of the stacked cooler in Example 1 (corresponding to a cross section taken along the line III-III in FIG. 2). FIG. 3 is an explanatory view showing a reinforcing plate in the first embodiment. The V arrow directional view in FIG. FIG. 6 is an explanatory view showing a stacked type cooler in Example 2. FIG. 9 is a partial cross-sectional view showing a stacked cooler in Example 3. FIG. 9 is a partial cross-sectional view showing a stacked cooler in Example 4.

  In the stacked cooler, the heat exchanging unit is disposed between the front end cooling pipe, the rear end cooling pipe disposed at the rear end in the arrangement direction, and the front end cooling pipe and the rear end cooling pipe. It is preferable that the rigidity of the front end cooling pipe is larger than the rigidity of the intermediate cooling pipe. In this case, it is possible to suppress an increase in the weight and material cost of the intermediate cooling pipe. Thereby, a deformation | transformation can be reliably prevented, reducing the weight and cost reduction of the said multilayer cooler.

  The rigidity of the front end cooling pipe is preferably larger than the rigidity of the rear end cooling pipe. In this case, by making the rigidity of the front end cooling pipe the largest among the plurality of cooling pipes, it is possible to suppress an increase in weight and material cost of the intermediate cooling pipe and the rear end cooling pipe. . Thereby, a deformation | transformation can be reliably prevented, reducing the weight and cost reduction of the said multilayer cooler.

Further, as the rigidity improving means, further comprising a reinforcing plate superimposed on the front end cooling pipes, reinforcing plates, joined to the periphery of the connecting portion between the refrigerant inlet and the refrigerant discharge pipe at the front end cooling pipe It is preferable to have a joined portion. In this case, the rigidity of the front end cooling pipe can be reliably and easily improved by using the reinforcing plate. Thereby, a deformation | transformation of the said front-end cooling pipe can be prevented reliably.

Example 1
The Example concerning the said laminated cooler is described with reference to FIGS.
As shown in FIGS. 1 to 3, the stacked cooler 1 includes a heat exchanging unit 10 in which a plurality of cooling pipes 2 are arranged side by side, a refrigerant introduction pipe 41 that introduces a refrigerant into the refrigerant flow path 20, and a refrigerant flow And a refrigerant discharge pipe 42 for discharging the refrigerant from the passage 20.
The plurality of cooling pipes 2 have a refrigerant flow path 20 for circulating the refrigerant, and the adjacent cooling pipes 2 are connected to each other and a semiconductor module 5 as a heat generating component is disposed between the two cooling pipes 2. It arrange | positions side by side so that the arrangement | positioning space | gap 11 may be formed.

The refrigerant introduction pipe 41 and the refrigerant discharge pipe 42 are extended in the arrangement direction X from the front end cooling pipe 21 arranged at the front end which is one end in the arrangement direction X of the plurality of cooling pipes 2 among the plurality of cooling pipes 2. Yes.
The stacked cooler 1 includes a rigidity improving means 3 that improves the rigidity of the front end cooling pipe 21.

This will be described in more detail below.
As shown in FIGS. 1 and 2, in this example, the direction in which the cooling pipes 2 of the stacked cooler 1 are arranged is the arrangement direction X, the longitudinal direction of the cooling pipe 2 is the horizontal direction Y, and the arrangement direction X and the horizontal A direction perpendicular to both of the directions Y will be described as a vertical direction Z.
In the arrangement direction X, the direction in which the refrigerant introduction pipe 41 and the refrigerant discharge pipe 42 protrude is defined as the front, and the opposite side is defined as the rear. Further, in the vertical direction Z, the side from which the main electrode terminal 512 of the semiconductor module 5 protrudes is indicated as the lower side, and the opposite side is indicated as the upper side.
Note that the front-rear direction X, the lateral direction Y, and the up-down direction Z are for convenience and are not limited thereto.

As shown in FIGS. 1 and 2, the stacked cooler 1 of this example is for cooling a plurality of semiconductor modules 5 in a power conversion device 6.
The power conversion device 6 includes a semiconductor unit 61 composed of the stacked cooler 1 and a plurality of semiconductor modules 5, and a case 7 that accommodates the semiconductor unit 61.

As shown in FIGS. 1 and 2, the case 7 that houses the semiconductor unit 61 includes a bottom portion 71 that is disposed below, and a wall portion 72 that is erected upward from the outer peripheral edge of the bottom portion 71. .
The bottom 71 has a rectangular shape larger than the outer shape of the semiconductor unit 61 as viewed from above.

  The wall portion 72 has a rectangular cylindrical shape standing upward from the entire outer peripheral edge of the bottom portion 71. In addition, a pair of through holes 721 for inserting and arranging the refrigerant introduction pipe 41 and the refrigerant discharge pipe 42 are formed in the wall portion 72 arranged forward.

  As shown in FIGS. 1 and 2, the plurality of semiconductor modules 5 constituting the semiconductor unit 61 include a main body 511 having a switching element, a plurality of control terminals 513 extending upward from the main body 511, and the main body 511. And a plurality of main electrode terminals 512 extending downward.

The semiconductor module 5 includes a switching element such as an IGBT (Insulated Gate Bipolar Transistor) or a MOSFET (MOS field effect transistor). The main body 511 in the semiconductor module 5 of this example has a flat plate shape, and is formed by resin-molding one switching element.
A control terminal 513 formed so as to extend upward from the main body 511 is connected to a control circuit board (not shown), and receives a control current for controlling the switching element.

  As shown in FIGS. 1 to 3, the stacked cooler 1 that cools the plurality of semiconductor modules 5 introduces the refrigerant into the heat exchange section 10 in which the plurality of cooling pipes 2 are arranged and the refrigerant flow path 20. A refrigerant introduction pipe 41 and a refrigerant discharge pipe 42 for discharging the refrigerant from the refrigerant flow path 20 are provided.

  The plurality of cooling pipes 2 constituting the heat exchanging unit 10 have a refrigerant flow path 20 through which a refrigerant flows. Adjacent cooling pipes 2 are connected to each other and the semiconductor module 5 is disposed between them. Are arranged side by side so as to form an arrangement space 11 for the purpose. The plurality of cooling pipes 2 include a front end cooling pipe 21 disposed at the front end of the heat exchange unit 10, a rear end cooling pipe 22 disposed at the rear end, the front end cooling pipe 21 and the rear end. An intermediate cooling pipe 23 disposed between the cooling pipe 22 and the cooling pipe 22 is provided.

  In this example, the cooling pipe 2 is disposed between the front outer shell plate 211 disposed on the front side, the rear outer shell plate 212 disposed on the rear side, and the front outer shell plate 211 and the rear outer shell plate 212. And an intermediate plate 213 formed thereon.

  When the front outer shell plate 211 and the rear outer shell plate 212 are joined, a gap forming the refrigerant flow path 20 is formed between them, and the refrigerant flow path 20 is divided into two in the front-rear direction by the intermediate plate 213. Has been. The plurality of cooling pipes 2 are arranged so as to sandwich the semiconductor module 5 from both sides, and adjacent cooling pipes 2 are connected to each other by connecting pipes 43 in the vicinity of both ends in the lateral direction Y.

  As shown in FIGS. 1 to 3, the refrigerant introduction pipe 41 and the refrigerant discharge pipe 42 are extended forward with the front end cooling pipe 21 as a base end. The refrigerant introduction pipe 41 and the refrigerant discharge pipe 42 are expanded in two stages while being extended from the base end side pipe parts 411 and 421 in the stacking direction X, and the front end part arranged on the front side is the front end. Side tube portions 412 and 422 are formed. That is, intermediate tube portions 413 and 423 having outer diameters intermediate between the proximal end side tube portions 411 and 421 and the distal end side tube portions 412 and 422 are formed, and the proximal end side tube portion 411 is formed. 421 and intermediate tube portions 413 and 423 and tapered step portions 414 and 424 are formed at the boundary portions between the intermediate tube portions 413 and 423 and the distal end side tube portions 412 and 422, respectively.

In this example, the refrigerant introduction pipe 41 and the refrigerant discharge pipe 42 are formed by press molding together with the front outer shell plate 211 of the front end cooling pipe 21 at a part of the base end side of the base end side pipe portions 411 and 421. The tip side from this is formed by another member and then joined.
The refrigerant introduction pipe 41 and the refrigerant discharge pipe 42 are arranged substantially coaxially with the connection pipe 43 in the vicinity of both end portions in the lateral direction Y, and a pair of through holes 721 formed in the wall portion 72 arranged in front of the case 7. Are respectively inserted and arranged.

  In the stacked cooler 1, the refrigerant introduced from the refrigerant introduction pipe 41 appropriately passes through the connection pipe 43, is distributed to each cooling pipe 2, and circulates in the longitudinal direction (lateral direction Y). The refrigerant exchanges heat with the semiconductor module 5 while flowing through each cooling pipe 2. The refrigerant whose temperature has increased due to heat exchange passes through the downstream connection pipe 43 and is led to the refrigerant discharge pipe 42 and discharged. Examples of the refrigerant include natural refrigerants such as water and ammonia, water mixed with ethylene glycol antifreeze, fluorocarbon refrigerants such as fluorinate, chlorofluorocarbon refrigerants such as HCFC123 and HFC134a, and alcohol refrigerants such as methanol and alcohol. A refrigerant such as a ketone-based refrigerant such as acetone can be used.

As shown in FIGS. 1 to 3, the front end cooling pipe 21 in the stacked cooler 1 includes a reinforcing plate 31 as a rigidity improving means 3 for improving the rigidity of the front end cooling pipe 21, and a temporary holding of the reinforcing plate 31. The engaging claw 25 is provided.
The reinforcing plate 31 is made of a substantially rectangular flat plate, and is joined to the front surface of the front end cooling pipe 21 at the joining portion 312 so that the longitudinal direction is the horizontal direction Y and the normal direction is the alignment direction X.

  As shown in FIGS. 4 and 5, both end portions in the lateral direction Y of the reinforcing plate 31 have substantially U-shaped plate end recesses 311 formed so as to be recessed inward in the lateral direction Y. A refrigerant introduction pipe 41 and a refrigerant discharge pipe 42 are disposed inside the recess 311 (FIG. 2). Further, the width of the reinforcing plate 31 in the vertical direction Z is set to be the same as the width of the front end cooling pipe 21.

  The reinforcing plate 31 has a joint portion 312 that is joined to the periphery of the connection portion 24 with the refrigerant introduction pipe 41 and the refrigerant discharge pipe 42 in the front end cooling pipe 21. The joint 312 is formed along the inner peripheral edge of the plate end recess 311. In this example, the joining portion 312 has a substantially C shape around the connection portion 24 (FIG. 3) along about a half circumference on the center side in the lateral direction Y of the front end cooling pipe 21. The entire surface of the bonding portion 312 forms a protrusion 313 that protrudes toward the front end cooling pipe 21. In this example, the entire surface of the bonding portion 312 is the protrusion 313, but the protrusion 313 may be partially formed on the bonding portion 312.

  A pair of engaged portions 32 engaged with the engaging claws 25 are formed at both ends in the lateral direction Y of the reinforcing plate 31. The engaged portions 32 are formed so as to extend along the surface of the front end cooling pipe 21 and extend outward from the reinforcing plate 31 in the lateral direction Y at positions corresponding to the engaging claws 25 of the front end cooling pipe 21. Yes. Further, as shown in FIG. 5, a thin portion 33 is formed between the joint portion 312 and the engaged portion 32 in the reinforcing plate 31. In the arrangement direction X, the thickness of the thin portion 33 is set smaller than the thickness of the joint portion 312.

  Before the front end cooling portion 21 and the reinforcing plate 31 are joined, the temporarily held reinforcing plate 31 is joined by brazing the joining portion 312 to the front surface of the front end cooling pipe 21. Thus, by joining the reinforcing plate 31, the rigidity of the front end cooling pipe 21 becomes larger than the rigidity of the rear end cooling pipe 22 and the intermediate cooling pipe 23.

  As shown in FIG. 1, the semiconductor unit 61 including the stacked cooler 1 and the plurality of semiconductor modules 5 is arranged in the arrangement direction from the side opposite to the side where the refrigerant introduction pipe 41 and the refrigerant discharge pipe 42 in the arrangement direction X are connected. It is pressed by a spring member 73 that biases X. A contact plate 74 for preventing deformation of the rear end cooling pipe 22 is disposed between the spring member 73 and the rear end cooling pipe 22.

Hereinafter, the function and effect of this example will be described.
The stacked cooler 1 includes a rigidity improving means 3 that improves the rigidity of the front end cooling pipe 21. Therefore, it is possible to prevent the front end cooling pipe 21 from being deformed when an external force is applied to the refrigerant introduction pipe 41 and the refrigerant discharge pipe 42. This prevents the front end cooling pipe 21 from being deformed even when the diameter of the connecting portion 24 of the refrigerant introduction pipe 41 and the front end cooling pipe 21 in the refrigerant discharge pipe 42 is reduced in order to reduce the size of the heat exchanging section 10. be able to. Thereby, size reduction of the multilayer cooler 1 can be achieved while suppressing deformation when external force is applied to the refrigerant introduction pipe 41 and the refrigerant discharge pipe 42.

  The heat exchanging unit 10 includes a front end cooling pipe 21, a rear end cooling pipe 22 disposed at the rear end in the arrangement direction X, and an intermediate cooling disposed between the front end cooling pipe 21 and the rear end cooling pipe 22. The rigidity of the front end cooling pipe 21 is larger than the rigidity of the intermediate cooling pipe 23 and the rear end cooling pipe 22. Therefore, by making the rigidity of the front end cooling pipe 21 the largest among the plurality of cooling pipes 2, it is possible to suppress an increase in the weight and material cost of the intermediate cooling pipe 23 and the rear end cooling pipe 22. Thereby, deformation | transformation can be prevented reliably, reducing the weight and cost reduction of the multilayer cooler 1.

  Further, the rigidity improving means 3 is composed of a reinforcing plate 31 superimposed on the front end cooling pipe 21, and the reinforcing plate 31 is joined around the connection portion 24 of the front end cooling pipe 21 to the refrigerant introduction pipe 41 and the refrigerant discharge pipe 42. The joined portion 312 is provided. Therefore, the rigidity of the front end cooling pipe 21 can be reliably and easily improved using the reinforcing plate 31. Thereby, the deformation | transformation of the front-end cooling pipe 21 can be prevented reliably.

  Further, the reinforcing plate 31 has a protrusion 313 protruding toward the front end cooling pipe 21 at the joint 312. Therefore, the protrusion 313 can be reliably brought into contact with the front end cooling pipe 21. Thereby, the reinforcing plate 31 and the front end cooling pipe 21 can be reliably joined at the joining portion 312.

  The front end cooling pipe 21 has an engaging claw 25 that holds the reinforcing plate 31, and the reinforcing plate 31 has an engaged portion 32 that can be engaged with the engaging claw 25. By engaging the joint claw 25, the engagement claw 25 and the engaged portion 32 are engaged, and the reinforcing plate 31 can be temporarily held in the front end cooling pipe 21. Therefore, the joining work of the reinforcing plate 31 and the front end cooling pipe 21 can be easily performed. Thereby, the productivity of the stacked cooler 1 can be improved.

  Further, the reinforcing plate 31 has a thin portion 33 formed between the joint portion 312 and the engaged portion 32 with a thickness smaller than the thickness of the joint portion 312. Therefore, when a force is applied to the engaged portion 32, it is possible to prevent the force from being transmitted to the joint portion 312 by deforming the thin portion 33. Thereby, the deformation | transformation in the junction part 312 can be prevented.

  As described above, according to the stacked cooler 1 of this example, it is possible to reduce the size while suppressing deformation when an external force is applied to the refrigerant introduction pipe 41 and the refrigerant discharge pipe 42.

  In this example, the one-piece reinforcing plate 31 is used. However, the present invention is not limited to this, and the reinforcing plate 31 divided into the refrigerant introduction pipe 41 side and the refrigerant discharge pipe 42 side can also be used. Further, as shown in this example, the reinforcing plate 31 may be joined to the front surface of the front end cooling pipe 21 or may be joined to the rear surface of the front end cooling surface.

(Example 2)
This example is an example of a stacked cooler in which the shape of the cooling pipe is partially changed as shown in FIG.
In the laminated cooler 1 of this example, a cooling pipe 2 having an increased width in the vertical direction Z is used.

  As shown in FIG. 6, the cooling pipe 2 of this example has a pair of taper portions 26 formed so as to widen from both ends toward the center when viewed from the arrangement direction X, and a pair of taper portions 26. And a widened cooling surface 27 that sandwiches the semiconductor module 5.

The reinforcing plate 31 joined to the front end cooling pipe 21 is formed in a shape along the outer shape of the cooling pipe 2 and is formed so as to widen from both ends toward the center when viewed from the arrangement direction X. A pair of plate taper portions 34 and a plate widening portion 35 formed between the pair of plate taper portions 34.
Of the reference numerals used in this example or the drawings relating to this example, the same reference numerals as those used in the first embodiment represent the same components as in the first embodiment unless otherwise specified.

Also in this example, the same effect as Example 1 can be obtained.
Moreover, the reinforcing plate 31 shown in Example 1 can also be used for the widened cooling pipe 2.

(Example 3)
This example shows an example of the rigidity improving means as shown in FIG.
In the laminated cooler 1 of this example, as the rigidity improving means 3, the thickness of the front outer shell plate 211 of the front end cooling pipe 21 is made larger than the thickness of the rear outer shell plate 212 and the intermediate plate 213. It is.
The refrigerant introduction pipe 41 and the refrigerant discharge pipe 42 are formed by separate members from the front outer shell plate 211, and are fitted to the front outer shell plate 211 and brazed.
Of the reference numerals used in this example or the drawings relating to this example, the same reference numerals as those used in the first embodiment represent the same components as in the first embodiment unless otherwise specified.

Also in this example, the same effect as Example 1 can be obtained.
In this example, the thickness of the front outer shell plate 211 is increased, but the thickness of the rear outer shell plate 212 may be increased.

Example 4
This example shows another example of the rigidity improving means as shown in FIG.
As shown in FIG. 8, in the laminated cooler 1 of this example, as the rigidity improving means 3, the thickness of the intermediate plate 213 constituting the front end cooling pipe 21 is changed to the front outer shell plate 211 and the rear outer shell plate 212. It is a bigger one.
Of the reference numerals used in this example or the drawings relating to this example, the same reference numerals as those used in the first embodiment represent the same components as in the first embodiment unless otherwise specified.
Also in this example, the same effect as Example 1 can be obtained.

DESCRIPTION OF SYMBOLS 1 Stack type cooler 10 Heat exchange part 11 Space | gap 2 Cooling pipe 20 Refrigerant flow path 21 Front end cooling pipe 3 Rigidity improvement means 41 Refrigerant introduction pipe 42 Refrigerant discharge pipe

Claims (6)

Arrangement for arranging a plurality of cooling pipes (2) having a refrigerant flow path (20) for circulating a refrigerant, and connecting the adjacent cooling pipes (2) to each other and a heat generating component (5) between the two. A heat exchange section (10) arranged side by side so as to form a void (11);
A refrigerant introduction pipe (41) for introducing the refrigerant into the refrigerant flow path (20);
A refrigerant discharge pipe (42) for discharging the refrigerant from the refrigerant flow path (20),
The refrigerant introduction pipe (41) and the refrigerant discharge pipe (42) are front end cooling arranged at a front end which is one end of the plurality of cooling pipes (2) in the arrangement direction of the plurality of cooling pipes (2). Extending from the tube (21) in the line-up direction,
Comprising rigidity improving means (3, 31, 211, 213) for improving the rigidity of the front end cooling pipe (21);
The front-end cooling pipe (21) is arranged on the front side with a front outer shell plate (211) and on the rear side, and is joined to the front outer shell plate (211) to join the front outer shell plate (21). 211) and a rear outer shell plate (212) that forms an air gap that forms the refrigerant flow path (20).
The refrigerant introduction pipe (41) and the refrigerant discharge pipe (42) are joined to the front outer shell plate (211),
As the rigidity improving means (3, 31, 211, 213), at least the thickness of the front outer shell plate (211) is made larger than the thickness of the rear outer shell plate (212) , and A reinforcing plate (31) superimposed on the front end cooling pipe (21);
The reinforcing plate (31) has a joint portion (312) joined to the periphery of the connection portion (24) between the refrigerant introduction pipe (41) and the refrigerant discharge pipe (42) in the front end cooling pipe (21). Have
The laminated cooler (1), wherein a thickness of the reinforcing plate (31) is larger than a thickness of the front outer shell plate (211 ).   The heat exchange section (10) includes the front end cooling pipe (21), a rear end cooling pipe (22) disposed at the rear end in the arrangement direction, the front end cooling pipe (21), and the rear end cooling pipe. (22), and the rigidity of the front end cooling pipe (21) is larger than the rigidity of the intermediate cooling pipe (23). The stacked cooler (1) according to claim 1, wherein:   The stacked cooler (1) according to claim 2, wherein the rigidity of the front end cooling pipe (21) is larger than the rigidity of the rear end cooling pipe (22). The said reinforcement plate (31) has the projection part (313) which protruded toward the said front-end cooling pipe (21) in the said junction part (312), Any of Claims 1-3 characterized by the above-mentioned. The stacked cooler (1) according to any one of the above. The front end cooling pipe (21) has an engaging claw (25) for holding the reinforcing plate (31), and the reinforcing plate (31) is engageable with the engaging claw (25). It has an engaged part (32), and by engaging the engaging claw (25), it engages with the engaging claw (25) and the engaged part (32), and the front end The laminated cooler (1) according to claim 4 , wherein the reinforcing plate (31) can be temporarily held in the cooling pipe (21). In the reinforcing plate (31), a thin wall portion (33) formed between the joint portion (312) and the engaged portion (32) with a thickness smaller than the thickness of the joint portion (312). The stacked cooler (1) according to claim 5 , wherein

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