JP2015025405A - Heat exchanger and heat exchange device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve the longer life of a heat exchanger.SOLUTION: A heat exchanger 30 includes: a core case 31 formed into a cylindrical shape; heat exchange tubes 34 that are stacked within this core case 31 and into which a first heat medium flows; and an upstream end plate 32 and a downstream end plate 33 penetrating and supporting end portions of the heat exchange tubes 34 and closing respective end portions of the core case 31. The heat exchanger 30 performs heat exchange between the first heat medium and a second heat medium flowing around an outer circumference of each heat exchange tube 34. Each of the upstream end plate 32 and the downstream end plate 33 includes: a connection member 43 connected to the core case 31; and a bottom plate 44 that is joined to this connection member 43 and into which the heat exchange tubes 34 are inserted. The bottom plate 44 is thinner than the connection member 43.

Description

  The present invention relates to a heat exchanger and a heat exchange device on which the heat exchanger is mounted.

  The heat exchanger is a device that performs heat exchange between a first heat medium that flows on the inner periphery of the heat exchange tube and a second heat medium that flows on the outer periphery. It is known that a heat exchanger is mounted on a heat exchange device (see, for example, Patent Document 1, page 4, FIG. 1).

  As shown in FIG. 11, the exhaust heat recovery apparatus 100 as a heat exchange device includes a heat recovery path 102 in which a heat exchanger 110 is disposed to perform heat exchange, and heat that bypasses the heat recovery path 102. And a detour 103 that does not perform exchange.

  The heat exchanger 110 includes a core case 111, two end plates 112 and 113 that close the ends of the core case 111, respectively, and an exhaust gas that is hung between the two end plates 112 and 113. It consists of a plurality of flowing heat exchange tubes 115. Heat exchange is performed between the exhaust gas flowing inside the heat exchange tube 115 and the medium flowing outside. Such a heat exchanger 110 has problems as described in the next figure.

  As shown in FIG. 12, the heat exchange tube 115 is joined to the end plate 112 by brazing. When the high-temperature exhaust gas flows into the heat exchange tube 115, the heat exchange tube 115 also becomes high temperature. Due to the high temperature, the heat exchange tube 115 is stretched as indicated by the white arrow.

  Since the heat exchange tube 115 is joined to the end plate 112, a load is applied to the end plate 112 due to the force by which the heat exchange tube 115 extends. If the load applied to the end plate 112 can be reduced, it is desirable from the viewpoint of extending the life.

JP 2012-184681 A

  An object of the present invention is to extend the life of a heat exchanger.

The invention according to claim 1 includes a core case formed in a cylindrical shape, a heat exchange tube that is stacked inside the core case and through which the first heat medium flows, and a flow direction of the first heat medium. As an reference, an upstream end plate that supports the upstream end of the heat exchange tube and closes the upstream end of the core case, and a downstream end of the heat exchange tube that penetrates and supports the core case. A heat exchanger that includes a downstream end plate that closes a downstream end, and performs heat exchange between the first heat medium and a second heat medium that flows around the outer periphery of the heat exchange tube;
The upstream end plate is composed of an upstream connection member connected to the core case, and an upstream bottom plate joined to the upstream connection member and into which the heat exchange tube is inserted,
The upstream bottom plate is thinner than the upstream connecting member.

According to a second aspect of the present invention, the downstream end plate is connected to the downstream connecting member connected to the core case, and the downstream where the heat exchange tube is inserted while being joined to the downstream connecting member. It consists of a side bottom plate,
The downstream end plate is characterized in that the downstream bottom plate is arranged on the downstream side of the downstream connection member.

In the invention according to claim 3, the upstream bottom plate is formed with a burring portion into which the heat exchange tube is inserted,
The part between these burring parts is characterized by being formed in step shape in sectional view.

In the invention according to claim 4, the upstream bottom plate includes an upstream general surface joined to the upstream connecting member and an upstream bulging surface bulging from the upstream general surface,
A burring portion into which the heat exchange tube is inserted is formed on the upstream bulging surface.

According to a fifth aspect of the invention, the downstream end plate is connected to the downstream connecting member connected to the core case, and the downstream where the heat exchange tube is inserted while being joined to the downstream connecting member. It consists of a side bottom plate,
The upstream bottom plate is formed with an upstream burring portion into which the heat exchange tube is inserted,
The downstream bottom plate is formed with a downstream burring portion into which the heat exchange tube is inserted,
The tip of the upstream burring portion is arranged toward the upstream side,
The tip of the downstream burring portion is arranged toward the downstream side.

In the invention according to claim 6, the upstream connection member includes a bottom portion to which the upstream bottom plate is joined, and a wall portion raised from the bottom portion.
The wall extends upstream;
The upstream bottom plate is formed with an upstream burring portion into which the heat exchange tube is inserted,
The front end of the upstream burring portion is arranged toward the upstream side.

The invention according to claim 7 is characterized in that the upstream connection member includes a bottom portion to which the upstream bottom plate is joined, and a wall portion raised from the bottom portion.
The wall extends downstream,
The upstream bottom plate is formed with an upstream burring portion into which the heat exchange tube is inserted,
The tip of the upstream burring portion is arranged toward the downstream side.

The invention according to claim 8 is a heat exchange device in which the heat exchanger according to any one of claims 1 to 7 is mounted,
A branching section that introduces exhaust gas as the first heat medium and branches the introduced first heat medium into two flow paths;
A first flow path extending from the branch portion;
A second flow path extending from the branch portion along the first flow path;
The heat exchanger attached to the second flow path and recovering energy from the heat of the first heat medium;
It consists of a valve provided so that the 1st channel or the 2nd channel can be opened and closed.

  In the invention according to claim 1, the upstream end plate is composed of two members, the upstream connecting member and the upstream bottom plate, and the thickness of the upstream bottom plate into which the heat exchange tube is inserted is equal to that of the upstream connecting member. Thinner than the plate thickness. That is, the bending rigidity of the upstream bottom plate is weaker than that of the upstream connecting member. For this reason, the upstream bottom plate is more easily bent than the upstream connecting member. Since the heat exchange tube is inserted in the portion where bending is easy, the elongation of the heat exchange tube can be absorbed by bending. Thereby, the load added to a heat exchange tube can be reduced, and the lifetime improvement of a heat exchanger can be aimed at.

  In the invention which concerns on Claim 2, the downstream end plate has arrange | positioned the downstream bottom plate in the downstream rather than the downstream connection member. Thereby, a 2nd heat carrier can be poured to the site | part enclosed by the downstream connection member and the downstream bottom plate. The core case can be reduced in size by the amount corresponding to this portion, and the entire heat exchanger can also be reduced in size.

  In the invention which concerns on Claim 3, the site | part between burring parts is formed in step shape in sectional view. As a result, it is possible to secure a large absorption allowance for stress caused by heat, and to obtain a higher stress absorption effect.

  In the invention which concerns on Claim 4, the burring part in which a heat exchange tube is inserted is formed in the upstream bulging surface which bulges from the upstream general surface. A step is formed at the boundary between the upstream general surface and the upstream bulging surface. Due to this step, a large absorption allowance for stress caused by heat can be secured, and a higher stress absorption effect can be obtained. On the other hand, the burring portion is formed on the bulging surface. For this reason, a plurality of burring portions can be formed close to each other. Thereby, the compactness of the heat exchanger can be achieved.

  In the invention which concerns on Claim 5, the front-end | tip of an upstream burring part is arrange | positioned toward an upstream, and the front-end | tip of a downstream burring part is arrange | positioned toward the downstream. When assembling the heat exchanger, the heat exchange tube is inserted into the burring part. At this time, since the tips of the upstream and downstream burring portions are directed in the insertion direction, the heat exchange tube can be easily inserted into the burring portion. A burring part can be used as a guide, and assemblability improves.

  In the invention which concerns on Claim 6, the wall part of an upstream connection member is extended toward an upstream, and the front-end | tip of an upstream burring part is arrange | positioned toward the upstream. Thereby, since the direction in which the deformation direction by the heat of the upstream side connection member and the heat extension direction of the heat exchange tube and the direction of exerting the stress of the bottom plate on the upstream side coincide with each other, a higher stress absorption effect can be obtained.

  In the invention which concerns on Claim 7, the wall part of an upstream connection member is extended toward a downstream, and the front-end | tip of an upstream burring part is arrange | positioned toward the downstream. Thereby, since the direction in which the deformation direction by the heat of the upstream side connection member and the heat extension direction of the heat exchange tube and the direction of exerting the stress of the bottom plate on the upstream side coincide with each other, a higher stress absorption effect can be obtained.

  In the invention which concerns on Claim 8, the heat exchanger by this invention is mounted in the heat exchange device. A heat exchange device is a device in which hot exhaust gas flows and is used under harsh conditions. By adopting the heat exchanger according to the present invention, the life of the heat exchanger can be extended, and the life of the heat exchange device can be extended.

It is a top view of the waste heat recovery apparatus with which the heat exchanger by Example 1 was mounted. It is sectional drawing of the waste heat recovery apparatus shown by FIG. It is sectional drawing of the heat exchanger shown by FIG. FIG. 4 is an exploded view of the heat exchanger shown in FIG. 3. FIG. 5 is a view taken in the direction of arrow 5 in FIG. 3. FIG. 6 is an enlarged view of 6 parts in FIG. 3. It is a figure explaining the baseplate used for the heat exchanger by Example 2. FIG. It is a figure explaining the baseplate used for the heat exchanger by Example 3. FIG. It is a figure explaining the shaping | molding method of the baseplate shown by FIG. It is an exploded view explaining the example of a change of the heat exchanger shown by FIG. It is a figure explaining the basic composition of the conventional technology. It is a figure explaining the problem of the prior art shown by FIG. FIG.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.

An example in which the heat exchanger according to the first embodiment is mounted on the exhaust heat recovery apparatus will be described with reference to the drawings.
As shown in FIG. 1, the exhaust heat recovery apparatus 10 (heat exchange device 10) is connected to an inlet 11 through which exhaust gas (first heat medium) generated in the internal combustion engine is introduced, and to the inlet 11. A branching portion 12 that is connected to the branching portion 12 and that extends downstream from the inlet 11, and a second flow passage that extends from the branching portion 12 along the first passage 13. 14, a heat exchanger 30 that forms part of the second flow path 14 and transfers the heat of exhaust gas to a medium (second heat medium), and a thermoactuator 16 connected to the heat exchanger 30; It consists of a valve chamber 17 to which the downstream ends of the first and second flow paths 13 and 14 are connected, and a discharge port 18 that is connected to the valve chamber 17 and discharges exhaust gas. The valve chamber 17 also serves as a junction where the exhaust gas that has passed through the first or second flow path 13, 14 joins.

  As shown in FIG. 2, a valve 19 is accommodated in the valve chamber 17. The valve 19 is connected to a thermoactuator (FIG. 1, reference numeral thermoactuator 16), and closes the first flow path 13. At this time, the second flow path 14 is open, and the exhaust gas passes through the second flow path 14. On the other hand, when the valve 19 swings under a predetermined condition, the valve 19 closes the second flow path 14. At this time, the first flow path 13 is open, and the exhaust gas passes through the first flow path 13.

  Returning to FIG. 1, a medium introduction pipe 21 for introducing a medium is connected to the side of the heat exchanger 30. The heat exchanger 30 is connected to an actuator support member 22 that supports the thermoactuator 16. A medium discharge pipe 23 for discharging the medium is connected to the actuator support member 22.

  That is, the medium is introduced from the medium introduction pipe 21 into the heat exchanger 30. The introduced medium receives the heat of the exhaust gas in the heat exchanger 30 and is discharged from the medium discharge pipe 23. Details of the heat exchanger 30 will be described in detail in the following figures.

  As shown in FIG. 3, the heat exchanger 30 includes a substantially rectangular tube-shaped core case 31 in which a medium flows, and an upstream side and a downstream side that are attached so as to close the openings at both ends of the core case 31. The side end plates 32 and 33 and a plurality of heat exchange tubes 34 which are attached between the upstream and downstream end plates 32 and 33 and through which exhaust gas passes.

  As shown in FIG. 4, the upstream end plate 32 is connected to the core case 31 and has an upstream connection member 43 that is U-shaped in cross-section, and is joined to the upstream connection member 43 and a heat exchange tube. And an upstream side bottom plate 44 into which 34 is inserted.

  A plate material having a thickness T2 that is thinner than the plate thickness T1 of the upstream connection member 43 is used for the upstream side bottom plate 44. That is, the plate thickness T2 of the upstream side bottom plate 44 is thinner than the plate thickness T1 of the upstream side connection member 43. The plate thickness T1 of the upstream connection member 43 is desirably 1.2 mm to 2.0 mm, and the plate thickness T2 of the upstream bottom plate 44 is desirably 0.4 mm to 1.0 mm.

  The upstream connection member 43 includes a bottom 43a to which the upstream bottom plate 44 is joined, and a wall 43b that rises from the bottom 43a and extends upstream. An opening 43c opened in a rectangular shape is formed in the bottom 43a.

  The upstream bottom plate 44 is formed with an upstream burring portion 44 a into which the heat exchange tube 34 is inserted. Sites between these upstream burring portions 44a are formed in a substantially U shape in a sectional view. The basic configuration of the downstream end plate (FIG. 3, reference numeral 33) is the same. The upstream burring portion 44a is an insertion hole of the heat exchange tube 34 in which the vertical wall is integrally formed by burring.

  Referring also to FIG. 3, the downstream end plate 33 is connected to the core case 31 and has a U-shaped downstream connection member, and is joined to the downstream connection member 48 and a heat exchange tube. And a downstream bottom plate 49 into which 34 is inserted.

  The downstream connection member 48 includes a bottom portion 48a to which the downstream side bottom plate 49 is joined, and a wall portion 48b that rises from the bottom portion 48a and extends upstream. An opening 48c opened in a rectangular shape is formed in the bottom 48a. The upstream side end plate 32 and the downstream side end plate 33 are different in that the downstream side bottom plate 49 is attached to the surface on the side where the wall portion 48b of the bottom portion 48a extends. That is, the upstream-side bottom plate 44 is attached to a surface on the opposite side of the wall 43b of the bottom 43a.

  The downstream bottom plate 49 is formed with a downstream burring portion 49a into which the heat exchange tube 34 is inserted. Sites between these downstream burring portions 49a are formed in a substantially U shape in a sectional view. The downstream burring portion 49a is an insertion hole of the heat exchange tube 34 in which the vertical wall is integrally formed by burring.

  In the downstream end plate 33, the downstream bottom plate 49 is disposed downstream of the downstream connection member 48. Thereby, the medium can be flowed to a portion surrounded by the downstream connection member 48 and the downstream bottom plate 49. The core case 31 can be reduced in size by this part, and the heat exchanger 30 as a whole can also be reduced in size.

  The front end 44d of the upstream burring portion 44a is disposed toward the upstream side, and the front end 49d of the downstream burring portion 49a is disposed toward the downstream side. When the heat exchanger 30 is assembled, the heat exchange tube 34 is inserted into the upstream and downstream burring portions 44a and 49a. At this time, since the tips 44d and 49d of the upstream and downstream burring portions 44a and 49a are directed in the insertion direction, the heat exchange tube 34 can be easily inserted into the upstream and downstream burring portions 44a and 49a. The upstream and downstream burring portions 44a and 49a can be used as guides, and the assembly of the heat exchanger 30 is improved.

  As shown in FIG. 5, fins 37 are accommodated in the heat exchange tube 34. Both ends of the heat exchange tube 34 in the longitudinal direction are covered with the bottom 48 a of the downstream connection member 48.

  The bottom 48a of the downstream connection member 48 covers both longitudinal ends of the heat exchange tube 34 in which the fins 37 are accommodated. The fin 37 is a component joined to the inside of the heat exchange tube 34 by brazing or the like. Since the joining work is difficult, the fins 37 are not arranged at both ends in the longitudinal direction. The portion where the fins 37 are not arranged has a large flow path area, and therefore has a low resistance, so that more exhaust gas flows. However, the part where the fins 37 are not arranged has a small heat transfer area, and therefore the heat exchange efficiency is lower than other parts. For this reason, in order to prevent the exhaust gas from flowing to a place where the fins 37 are not disposed, both ends in the longitudinal direction of the heat exchange tube 34 are covered by the bottom 48a of the downstream connection member 48. Thereby, exhaust gas can be guide | induced to the site | part in which the fin 37 is arrange | positioned, and heat exchange efficiency can be improved.

  As shown in FIG. 6, the heat exchange tube 34 through which the high-temperature exhaust gas flows is elongated due to the heat of the exhaust gas. Since the upstream bottom plate 44 is thinner than the upstream connecting member 43, the upstream bottom plate 44 has a lower bending rigidity than the upstream connecting member 43. For this reason, the upstream side bottom plate 44 is more easily bent than the upstream side connection member 43. Since the heat exchanging tube 34 is inserted into a portion that is easily bent, the extension of the heat exchanging tube 34 can be absorbed by the bending. Thereby, the load added to the heat exchange tube 34 can be reduced, and the lifetime of the heat exchanger 30 can be extended.

  Referring also to FIG. 1, the heat exchanger 30 according to the present invention is mounted on the exhaust heat recovery apparatus 10. The exhaust heat recovery apparatus 10 is an apparatus that is used under severe conditions in which high-temperature exhaust gas flows. By adopting the heat exchanger 30 according to the present invention, the life of the heat exchanger 30 can be extended, and the life of the exhaust heat recovery apparatus 10 can be extended.

  As shown in FIG. 10, in the heat exchanger 30 according to the modified example, the wall portion 43 b extends downstream, and the upstream bottom plate 44 is formed with an upstream burring portion 44 a into which the heat exchange tube 34 is inserted. ing. The tip 44d of the upstream burring portion 44a is disposed toward the downstream side. Even in such a case, the predetermined effect of the present invention can be obtained.

Next, a second embodiment of the present invention will be described with reference to the drawings.
FIG. 7A shows the upstream bottom plate 44A employed in the heat exchanger of the second embodiment.

  As shown in FIGS. 7A and 7B, the upstream bottom plate 44A is formed with an upstream burring portion 44a into which a heat exchange tube (FIG. 3, reference numeral 34) is inserted. Sites between these upstream burring portions 44a are formed in a staircase shape in a sectional view.

  Even when such an upstream side bottom plate 44A is employed, the predetermined effect of the present invention can be obtained. In addition, a downstream side baseplate (FIG. 3, code | symbol 49) can also be set as such a structure.

Next, Embodiment 3 of the present invention will be described with reference to the drawings.
FIG. 8A shows the upstream bottom plate 44B employed in the heat exchanger of the third embodiment.

  As shown in FIGS. 8A and 8B, the upstream bottom plate 44B includes an upstream general surface 44b joined to the upstream connecting member (FIG. 3, reference numeral 43) and the upstream general surface. It consists of the upstream side bulging surface 44c bulging from the surface 44b. An upstream burring portion 44a into which a heat exchange tube (FIG. 3, reference numeral 34) is inserted is formed on the upstream bulging surface 44c.

  Even when such an upstream side bottom plate 44B is employed, the predetermined effect of the present invention can be obtained. In addition, a downstream side baseplate (FIG. 3, code | symbol 49) can also be set as such a structure. A method of forming the upstream side bottom plate 44B having such a shape will be described with reference to the next drawing.

  As shown in FIG. 9A, first, a plate material 61 as a material is prepared. The plate material 61 is pressed by the lower mold 62 and the upper mold 63 to form the upstream general surface 44b and the upstream bulging surface 44c that bulges from the upstream general surface 44b.

  Next, as shown in FIG. 9B, punching is performed on the upstream bulging surface 44 c by a punching press 64. Thereby, as shown in FIG. 9C, the upstream burring portion 44a is formed, and the upstream bottom plate 44B is completed.

  In addition, although the heat exchanger of this invention was applied to the exhaust-heat recovery apparatus in embodiment, it can also be applied to an EGR (Exhaust Gas Recirculation) cooler, a cogeneration system, and a thermoelectric power generation apparatus. Furthermore, the present invention can also be applied to objects other than those that exchange heat between the heat of exhaust gas and the medium.

  Further, the same effect can be obtained regardless of whether the upstream bottom plate is attached to the upstream surface or the downstream surface of the bottom of the upstream connecting member. Similarly, even if the downstream side bottom plate is attached to the upstream surface or the downstream surface of the bottom of the downstream connection member, the same effect can be obtained.

  Furthermore, the welding of the heat exchange tube to the upstream side bottom plate can employ laser welding, seam welding or the like in addition to brazing. The same applies to the joining of the heat exchange tube to the downstream side bottom plate. Furthermore, the same can be said for all the parts to be joined, such as joining of the upstream bottom plate to the upstream connection member or the downstream connection member. In addition, an arbitrary method can be selected as the welding method according to the object of the present invention.

  The heat exchanger of the present invention is suitable for an exhaust heat recovery apparatus.

  DESCRIPTION OF SYMBOLS 10 ... Waste heat recovery apparatus (heat exchange device), 12 ... Branch part, 13 ... 1st flow path, 14 ... 2nd flow path, 19 ... Valve, 30 ... Heat exchanger, 31 ... Core case, 32 ... Upstream side End plate 33 ... downstream end plate 34 ... heat exchange tube 43 upstream connection member 44, 44A, 44B upstream bottom plate 44a upstream burring section 44b upstream general surface 44c upstream Side bulging surface, 48: downstream connection member, 49: downstream bottom plate.

Claims (8)

A core case formed in a cylindrical shape, a heat exchange tube that is stacked inside the core case and in which the first heat medium flows, and upstream of the heat exchange tube based on the flow direction of the first heat medium An upstream end plate that penetrates and supports the side end and closes the upstream end of the core case; and a downstream side that penetrates and supports the downstream end of the heat exchange tube and closes the downstream end of the core case In a heat exchanger comprising an end plate and performing heat exchange between the first heat medium and a second heat medium that flows around the outer periphery of the heat exchange tube,
The upstream end plate is composed of an upstream connection member connected to the core case, and an upstream bottom plate joined to the upstream connection member and into which the heat exchange tube is inserted,
The heat exchanger according to claim 1, wherein a plate thickness of the upstream side bottom plate is thinner than a plate thickness of the upstream side connection member. The downstream end plate is composed of a downstream connection member connected to the core case and a downstream bottom plate joined to the downstream connection member and into which the heat exchange tube is inserted.
2. The heat exchanger according to claim 1, wherein the downstream end plate has the downstream bottom plate disposed downstream of the downstream connection member. The upstream bottom plate is formed with an upstream burring portion into which the heat exchange tube is inserted,
The heat exchanger according to claim 1 or 2, wherein a portion between the upstream burring portions is formed in a step shape in a cross-sectional view. The upstream bottom plate is composed of an upstream general surface joined to the upstream connecting member and an upstream bulging surface bulging from the upstream general surface,
The heat exchanger according to claim 1, wherein an upstream burring portion into which the heat exchange tube is inserted is formed on the upstream bulging surface. The downstream end plate is composed of a downstream connection member connected to the core case and a downstream bottom plate joined to the downstream connection member and into which the heat exchange tube is inserted.
The upstream bottom plate is formed with an upstream burring portion into which the heat exchange tube is inserted,
The downstream bottom plate is formed with a downstream burring portion into which the heat exchange tube is inserted,
The tip of the upstream burring portion is arranged toward the upstream side,
The heat exchanger according to claim 1, wherein a tip of the downstream burring portion is disposed toward the downstream side. The upstream connection member includes a bottom portion to which the upstream bottom plate is joined, and a wall portion raised from the bottom portion,
The wall extends upstream;
The upstream bottom plate is formed with an upstream burring portion into which the heat exchange tube is inserted,
The heat exchanger according to claim 1, wherein a tip of the upstream burring portion is disposed toward the upstream side. The upstream connection member includes a bottom portion to which the upstream bottom plate is joined, and a wall portion raised from the bottom portion,
The wall extends downstream,
The upstream bottom plate is formed with an upstream burring portion into which the heat exchange tube is inserted,
The heat exchanger according to claim 1, wherein a tip of the upstream burring portion is disposed toward the downstream side. A heat exchange device on which the heat exchanger according to any one of claims 1 to 7 is mounted,
A branching section that introduces exhaust gas as the first heat medium and branches the introduced first heat medium into two flow paths;
A first flow path extending from the branch portion;
A second flow path extending from the branch portion along the first flow path;
The heat exchanger attached to the second flow path and recovering energy from the heat of the first heat medium;
A heat exchange device comprising: a valve provided to open and close the first flow path or the second flow path.

Images