JP2017026208A - U-turn type heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a U-turn type heat exchanger which avoids a high temperature fluid before heat exchange bypassing a heat transfer pipe, and which can sufficiently cool the fluid returning after heat exchange.SOLUTION: A U-turn type heat exchanger 100 is the U-turn type heat exchanger including a heat exchange part 10 having heat transfer pipes 11 and an external cylinder 12. The external cylinder 12 is formed into a bottomed cylindrical shape in which one end is open and the other end is closed. A header 12b on a closed side of the external cylinder 12 allows an exhaust gas flowing in from one part of the heat transfer pipes 11 out of the plurality of laminated heat transfer pipes 11 to turn around, and allows it to make a U-turn to the other heat transfer pipes 11 out of the plurality of laminated heat transfer pipes 11. The U-turn type heat exchanger 100 includes a bypass valve 20 having a flap 22. Between the one end of the heat transfer pipe 11 and the flap 22, a partition part 40 is provided for closing a gap formed when the flap 22 switches a flow so as to flow the exhaust gas to the one part of the heat transfer pipes 11 of the heat exchange part 10.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a U-turn heat exchanger.

  Patent Document 1 discloses a U-turn heat exchanger in which a flange member is attached to the opening at the front end of the outer tube of the heat exchanger. In the U-turn heat exchanger of Patent Document 1, the flange member is provided with a partition on the flat plate so that the opening is divided into two vertically, and the flange member partition and the front end of the heat transfer tube Are welded in an overlapping state.

JP2013-88010A

  However, in the U-turn type heat exchanger of Patent Document 1, no gap is formed between the partition member of the flange member and the heat transfer tube, but there is no gap between the flap of the flow dividing portion and the partition member of the flange portion. Will be formed. For this reason, for example, high-temperature exhaust gas (fluid) flows into a gap formed between the flap and the partition so as to bypass the heat transfer tube. A part of the high-temperature fluid before heat exchange bypasses the heat transfer tube, so it may be mixed with the cooled fluid that has been heat exchanged in the heat transfer tube, and the fluid returned after heat exchange may not be sufficiently cooled. is there.

  The present invention has been invented to solve such a problem. The fluid before heat exchange avoids bypassing the heat transfer tube, and the fluid before heat exchange is mixed with the fluid to be returned after heat exchange. It aims at providing the U-turn type heat exchanger which can suppress that.

  A U-turn heat exchanger according to an aspect of the present invention includes a plurality of stacked heat transfer tubes that perform heat exchange between a fluid introduced from the outside and a refrigerant flowing inside, and a plurality of stacked heat transfer tubes. It is a U-turn type heat exchanger provided with the heat exchange part which has the outer cylinder to accommodate. The outer cylinder is formed in a bottomed cylinder shape having one end opened and the other end closed. The closed side of the outer cylinder changes the direction of the fluid flowing from some of the heat transfer tubes among the plurality of heat transfer tubes, and causes the other heat transfer tubes to make a U-turn. The U-turn type heat exchanger includes a flow dividing unit having a flap that switches a flow of fluid flowing through the heat exchange unit. Between the one end of the heat transfer tube and the flap, there is provided a partition portion that closes a gap formed when the flow is switched so that fluid flows through the heat exchange portion.

  According to such an aspect, the partition part is formed so as to close the gap between the flap and the heat transfer tube, so that it is possible to prevent the fluid before heat exchange from bypassing the heat transfer tube. Therefore, it can suppress that the fluid before heat exchange is mixed with the fluid after heat exchange with the heat exchanger tube.

It is a lineblock diagram of the U-turn type heat exchanger concerning a 1st embodiment of the present invention. It is sectional drawing of the U-turn type heat exchanger which concerns on 1st Embodiment. It is the figure which decomposed | disassembled the U-turn type heat exchanger which concerns on 1st Embodiment. It is a block diagram of the heat exchange part before attaching a partition part to a heat exchanger tube. It is a block diagram of the heat exchange part after attaching a partition part to a heat exchanger tube. It is sectional drawing of the U-turn type heat exchanger which concerns on 1st Embodiment which shows the state which the partition part attached to the heat exchanger tube of the heat exchange part, and the flap contacted. It is the figure which decomposed | disassembled the U-turn type heat exchanger which concerns on the 1st modification of 1st Embodiment. It is sectional drawing to which the partition part vicinity of the U-turn type heat exchanger which concerns on a 1st modification was expanded. It is sectional drawing to which the partition part vicinity of the U-turn type heat exchanger which concerns on a 2nd modification was expanded. It is sectional drawing of the U-turn type heat exchanger which concerns on 2nd Embodiment of this invention. It is sectional drawing to which the partition part vicinity of the U-turn type heat exchanger was expanded. It is a block diagram of the heat exchange part of the U-turn type heat exchanger which concerns on 3rd Embodiment of this invention. It is sectional drawing of the U-turn type heat exchanger which concerns on 3rd Embodiment. It is sectional drawing to which the partition part vicinity of the U-turn type heat exchanger which concerns on 3rd Embodiment was expanded. It is sectional drawing of the U-turn type heat exchanger which concerns on 4th Embodiment. It is sectional drawing to which the partition part vicinity of the U-turn type heat exchanger which concerns on 4th Embodiment was expanded. It is sectional drawing which shows the movable range of the flap of the U-turn type heat exchanger which concerns on 4th Embodiment. It is sectional drawing of the U-turn type heat exchanger which concerns on the modification of 4th Embodiment when the flap which formed the guide plate is opened. It is sectional drawing of the U-turn type heat exchanger which concerns on the modification of 4th Embodiment when the flap which formed the guide plate is closed.

  Embodiments of the present invention will be described below with reference to the drawings.

(First embodiment)
A U-turn heat exchanger 100 according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 3. FIG. 1 is a configuration diagram of a U-turn heat exchanger 100 according to the first embodiment of the present invention.

  The U-turn heat exchanger 100 is attached to a vehicle as an EGR (Exhaust Gas Recirculation) cooler for cooling exhaust gas after combustion, for example. As shown in FIG. 1, the U-turn heat exchanger 100 includes a heat exchanging unit 10 that exchanges heat between exhaust gas that is a high-temperature fluid and cooling water that is a refrigerant that flows inside, and a heat exchanging unit 10. And a bypass valve 20 as a flow dividing section that switches the flow by adjusting the flow of the exhaust gas flowing through the.

  FIG. 2 is a cross-sectional view of the U-turn heat exchanger 100.

  The heat exchange unit 10 includes a plurality of heat transfer tubes 11 stacked at intervals, an outer cylinder 12 that houses the plurality of heat transfer tubes 11, and a flange 13 that is connected to an end of the outer tube 12.

  The heat transfer tube 11 is a tube on a flat plate. Exhaust gas which is a fluid introduced from the outside flows outside the heat transfer tube 11. Inside the heat transfer tube 11, cooling water as a refrigerant flows. The heat transfer tube 11 performs heat exchange between the exhaust gas and the cooling water.

  The outer cylinder 12 has a shell 12a surrounding the outside of the heat transfer tube 11, and a header 12b attached to one end of the shell 12a, and accommodates a plurality of stacked heat transfer tubes 11. The other end of the shell 12 a is disposed on the bypass valve 20 side and connected to the flange 13. The header 12b covers one end of the shell 12a in a dome shape. The outer cylinder 12 is formed into a bottomed cylindrical shape having one end opened and the other end closed by a shell 12a and a header 12b, and a space independent from the outside is formed inside. The header 12 b changes the direction of the exhaust gas flowing from the outside of some of the heat transfer tubes 11 among the plurality of stacked heat transfer tubes 11 and makes a U-turn so as to flow to the outside of the other heat transfer tubes 11.

  The flange 13 is formed on the bypass valve 20 side of the heat exchange unit 10. An insertion hole for inserting the bolt 50 is formed in the flange 13.

  The bypass valve 20 includes a passage 21, a flap 22, and a flange 23.

  The passage 21 is formed in the bypass valve 20 as a space for flowing exhaust gas. The exhaust gas flows from the passage inlet 21a to the passage 21. The exhaust gas that has passed through the passage 21 flows from the passage outlet 21b to the outside.

  The flap 22 is formed by attaching a flat plate 22b to a rotatable cylindrical shaft 22a. The flap 22 is disposed near the center of the passage 21 so as to divide the passage 21 into an inlet side and an outlet side.

  The flange 23 is formed at the end of the bypass valve 20. The flange 23 is formed at a position facing the flange 13 of the heat exchange unit 10, and is internally threaded so that the bolt 50 can be screwed. The flange 23 is formed so as to slightly protrude outward from the flap 22, that is, toward the heat exchange unit 10. As described above, the flange 23 is formed so as to protrude from the flap 22, so that the flap 22 can be prevented from coming into contact with the heat transfer tube 11 and being damaged when being attached to the heat exchange unit 11. On the other hand, a gap is formed between the heat transfer tube 11 of the heat exchange unit 10 and the flap 22 so that the flange 23 protrudes from the flap 22.

  The exhaust gas flowing into the bypass valve 20 flows to the heat transfer tube 11 when the flap 22 is opened as shown in FIG. On the other hand, the exhaust gas flowing into the bypass valve 20 flows out of the bypass valve 20 through the passage 21 so as to bypass the heat transfer tube 11 when the flap 22 is closed. Thus, the flap 22 adjusts the flow rate of the fluid flowing through the heat transfer tube 11 by performing an opening / closing operation.

  A partition 40 is attached to the end of the heat transfer tube 11 of the heat exchange unit 10 so as to be in contact with the tip of the plate 22b of the flap 22.

  FIG. 3 is an exploded view of the U-turn heat exchanger 100.

  As shown in FIG. 3, the heat exchange unit 10 and the bypass valve 20 are connected by a bolt 50 via a gasket 30 in which a through hole is formed.

  The gasket 30 is sandwiched and compressed by the flange 13 of the heat exchange unit 10 and the flange 23 of the bypass valve 20 to close the gap between the flange 13 and the flange 23, thereby leaking internal exhaust gas or externally. Prevent foreign material from entering.

  The bolt 50 is inserted into the flange 13 of the heat exchange unit 10 and the gasket 30 and then inserted into the flange 23 of the bypass valve 20 and fixed.

  4A is a configuration diagram of the heat exchanging unit 10 before the partition portion 40 is attached to the heat transfer tube 11, and FIG. 4B is a configuration diagram of the heat exchanging portion 10 after the partition portion 40 is attached to the heat transfer tube 11.

  As shown in FIGS. 4A and 4B, the partitioning portion 40 is formed with a sandwiching portion 40a at the center and posture holding claws 40b at both ends. The partition part 40 is fixed by attaching the clamping part 40 a to the end part of the heat transfer tube 11. As shown in FIG. 4B, the partition 40 attached to the heat transfer tube 11 is held at a stable position by the posture holding claws 40 b formed at both ends coming into contact with the inside of the flange 13. The partition part 40 is fixed by welding such as brazing. The contact part 40c is formed on the side opposite to the sandwiching part 40a, and is located outside, that is, on the bypass valve 20 side when the partition part 40 is attached to the heat transfer tube 11.

  FIG. 5 is a cross-sectional view of the U-turn heat exchanger 100 showing a state in which the partition portion 40 attached to the heat transfer tube 11 of the heat exchange portion 10 and the flap 22 are in contact with each other. FIG. 5 is an enlarged view of the vicinity of the flap 22 of the U-turn heat exchanger 100.

In the U-turn type heat exchanger 100, the partition portion 40 sandwiches the tip of the heat transfer tube 11 by the sandwiching portion 40a and contacts the plate 22b of the flap 22 by the contact portion 40c. When the flap 22 is opened so that the exhaust gas flows through the heat transfer tube 11, the contact portion 40 c of the partition 40 and the plate 22 b of the flap 22 come into contact with each other, so that the plate 22 b and the end of the heat transfer tube 11 The gap formed between the two can be closed.
According to the U-turn heat exchanger 100 according to the first embodiment described above, the following effects can be obtained.

  The U-turn heat exchanger 100 accommodates a plurality of stacked heat transfer tubes 11 that exchange heat between exhaust gas introduced from the outside and cooling water flowing inside, and a plurality of stacked heat transfer tubes 11. A U-turn heat exchanger including a heat exchanging unit 10 having an outer cylinder 12. The outer cylinder 12 is formed in a bottomed cylinder shape having one end opened and the other end closed. The header 12b on the closing side of the outer cylinder 12 changes the direction of the exhaust gas flowing from some of the heat transfer tubes 11 among the plurality of heat transfer tubes 11, and the other of the plurality of heat transfer tubes 11 is stacked. The U-turn is made to the heat transfer tube 11. The U-turn heat exchanger 100 includes a bypass valve 20 having a flap 22 that switches the flow of exhaust gas flowing through the heat exchange unit 10. Between the one end of the heat transfer tube 11 and the flap 22, a partition portion that closes a gap formed when the flap 22 switches the flow so that the exhaust gas flows through a part of the heat transfer tube 11 of the heat exchange unit 10. 40 is provided.

  In the U-turn heat exchanger 100, the partition 40 is formed at the end of the heat transfer tube 11.

  According to the U-turn heat exchanger 100, the partition 40 is formed so as to close the gap between the flap 22 and the heat transfer tube 11, so that the exhaust gas before heat exchange bypasses the heat transfer tube 11. You can avoid that. Therefore, it can suppress that the exhaust gas before heat exchange is mixed with the exhaust gas after heat exchange with the heat exchanger tube 11. Further, since the high-temperature exhaust gas before heat exchange and the exhaust gas after cooling heat exchanged by the heat transfer tube 11 are not mixed, the exhaust gas returned after heat exchange can be sufficiently cooled.

  In the U-turn heat exchanger 100 according to the first embodiment, the partition 40 is formed at the end of the heat transfer tube 11, but as shown in FIG. 6, the plate 22b of the flap 22 is sandwiched. May be formed.

  FIG. 6 is an exploded view of the U-turn heat exchanger 100 according to the first modification of the first embodiment. FIG. 7 is an enlarged cross-sectional view of the vicinity of the partition portion 40 of the U-turn heat exchanger 100 according to the first modification of the first embodiment.

  In the first modification of the U-turn type heat exchanger 100, the partition 40 is configured such that the clamping part 40a holds the plate 22b of the flap 22 and the contact part 40c is connected to the end of the heat transfer tube 11 as shown in FIG. Contact. According to the modified example of the U-turn type heat exchanger 100, the gap between the flap 22 and the heat transfer tube 11 can be closed by the partition portion 40 formed so as to sandwich the plate 22b. The same effect as the U-turn heat exchanger 100 can be obtained.

  FIG. 8 is an enlarged cross-sectional view of the vicinity of the partition portion 40 of the U-turn heat exchanger 100 according to the second modification of the first embodiment.

  In the second modification of the U-turn type heat exchanger 100, the partition portion 40 is formed by bending between the sandwiching portion 40a and the contact portion 40c. For this reason, only the side of the tip of the contact portion 40c is in line contact with the plate 22b of the flap 22 and the contact area with the plate 22b is reduced, so that even when soot accumulates on the plate 22b, It is possible to prevent the wrinkles from moving to the partition portion 40 and sticking.

(Second Embodiment)
With reference to FIG.9 and FIG.10, the U-turn type heat exchanger 200 which concerns on 2nd Embodiment of this invention is demonstrated.

  FIG. 9 is a cross-sectional view of the U-turn heat exchanger 200, and FIG. 10 is an enlarged cross-sectional view of the vicinity of the partition 240 of the U-turn heat exchanger 200.

  In the U-turn heat exchanger 200 according to the second embodiment, the configuration of the partition portion 240 is different from that of the first embodiment. In the following embodiments, the same reference numerals are used for configurations that perform the same functions as those in the first embodiment, and redundant descriptions are omitted as appropriate.

  As shown in FIGS. 9 and 10, the partition portion 240 is disposed and fixed so as to partially overlap the plate 22 b of the flap 22.

  As shown in FIG. 10, the front end of the partition 240 is formed so as to protrude from the plate 22 b, and the flap 22 is opened so that the exhaust gas flows into the heat transfer tube 11. Contact. The partition 240 protruding from the plate 22 b is set to a length that does not interfere with the tip of the adjacent heat transfer tube 11 when the flap 22 is closed so that the exhaust gas bypasses the heat transfer tube 11.

  According to the U-turn heat exchanger 200 according to the second embodiment described above, the following effects can be obtained.

  In the U-turn heat exchanger 200, the partition portion 240 is formed on the flap 22. Moreover, a part of the partition part 240 is disposed so as to overlap the flap 22.

  According to the U-turn heat exchanger 200, when the flap 22 is opened, the gap formed between the flap 22 and the heat transfer tube 11 can be closed by the partition portion 240. The same effect as the U-turn heat exchanger 100 can be obtained.

(Third embodiment)
A U-turn heat exchanger 300 according to a third embodiment of the present invention will be described with reference to FIGS. 11 to 13.

  FIG. 11 is a configuration diagram of the heat exchange unit 10 of the U-turn heat exchanger 300.

  In the U-turn heat exchanger 300 of the third embodiment, as shown in FIG. 11, the partition portion 340 is integrally formed at the end of the heat transfer tube 11.

  12 is a cross-sectional view of the U-turn heat exchanger 300, and FIG. 13 is an enlarged cross-sectional view of the vicinity of the partition portion 340 of the U-turn heat exchanger 300.

  As shown in FIGS. 12 and 13, the plate 22 b of the flap 22 is in contact with a partition portion 340 formed integrally with the end of the heat transfer tube 11 when the exhaust gas is opened so as to flow into the heat transfer tube 11. To do.

  The partition part 340 is formed so as to protrude toward the plate 22b at the end of the heat transfer tube 11 disposed at a position closest to the plate 22b and facing the plate 22b when the flap 22 is closed.

  According to the U-turn heat exchanger 300 according to the above-described third embodiment, the following effects can be obtained.

  In the U-turn heat exchanger 300, the partition portion 340 is integrally formed at the end of the heat transfer tube 11. According to the U-turn heat exchanger 300, the gap formed between the flap 22 and the heat transfer tube 11 can be closed by the partition portion 340 when the flap 22 is opened. The same effect as the U-turn heat exchanger 100 can be obtained. Moreover, since the heat exchanger tube 11 and the partition part 340 are integrally formed, the number of parts can be reduced, and the number of processes such as processing steps and assembly steps can be reduced.

(Fourth embodiment)
A U-turn heat exchanger 400 according to a fourth embodiment of the present invention will be described with reference to FIGS. 14 to 16.

  14 is a cross-sectional view of the U-turn heat exchanger 400, and FIG. 15 is an enlarged cross-sectional view of the vicinity of the partition portion 440 of the U-turn heat exchanger 400.

  As shown in FIGS. 14 and 15, the partition portion 440 is integrally formed at the end of the bent end portion of the plate 22 b of the flap 22. Thus, since the partition part 440 is connected to the plate 22b at an angle, only the side of the tip of the contact part 440c is in line contact with the tip of the heat transfer tube 11.

  FIG. 16 is a cross-sectional view showing the movable range of the flap 22 of the U-turn type heat exchanger 400.

  As indicated by the two-dot chain line in FIG. 16, the flap 22 rotates about the shaft 22a as a rotation axis. The plate 22b is fixed to the shaft 22a at a position shifted from the rotation axis of the flap 22. The partition portion 440 is set to a length that does not interfere with the tip of the adjacent heat transfer tube 11 when the flap 22 is closed so that the exhaust gas bypasses the heat transfer tube 11.

  According to the U-turn heat exchanger 400 according to the above-described fourth embodiment, the following effects can be obtained.

  In the U-turn heat exchanger 400, the partition portion 440 is formed by bending the end portion of the flap 22.

  According to the U-turn type heat exchanger 400, the gap formed between the flap 22 and the heat transfer tube 11 can be closed by linearly contacting the partition portion 440 with the tip of the heat transfer tube 11, so that the first embodiment The same effects as those of the U-turn heat exchanger 100 can be obtained. Moreover, since the partition part 440 is in line contact with the heat transfer tube 11 and the contact area with the heat transfer tube 11 is reduced, even when soot accumulates on the heat transfer tube 11, the soot moves and adheres to the partition part 440. Can be prevented.

  The embodiment of the present invention has been described above. However, the above embodiment only shows a part of application examples of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiment. Absent.

  For example, the flap 22 may be formed with a guide plate 22c that guides the flow of exhaust gas. FIG. 17A is a cross-sectional view of the U-turn heat exchanger 400 when the flap 22 on which the guide plate 22c is formed is opened. FIG. 17B is a cross-sectional view of the U-turn heat exchanger 400 when the flap 22 on which the guide plate 22c is formed is closed.

  As shown in FIGS. 17A and 17B, the flap 22 has a guide plate 22c on the surface of the plate 22b on the side in contact with the shaft 22a.

  When the flap 22 is opened as shown in FIG. 17A, the guide plate 22 c guides the exhaust gas that has passed through the heat exchange unit 10 and is cooled to the passage outlet 21 b of the bypass valve 20. On the other hand, when the flap 22 is closed as shown in FIG. 17B, the guide plate 22c guides the exhaust gas bypassing the heat exchange unit 10 to the passage outlet 21b of the bypass valve 20.

  According to such a U-turn heat exchanger 400, the flow of exhaust gas is guided by the guide plate 22c of the flap 22, so that the exhaust gas can be efficiently flowed without generating turbulent flow or the like. The guide plate 22c may be applied not only to the U-turn heat exchanger 400 according to the fourth embodiment but also to the U-turn heat exchanger 100 according to the first embodiment.

  Further, the U-turn heat exchanger 100 or the like is not limited to the EGR cooler, and may be, for example, an exhaust heat recovery unit that heats the vehicle interior using recovered exhaust heat.

  Furthermore, in the above-described embodiment, the exhaust gas flows outside the heat transfer tube 11 and the cooling water flows inside. However, the exhaust gas flows inside the heat transfer tube 11 and the cooling water flows outside. There may be.

100, 200, 300, 400 U-turn type heat exchanger 10 Heat exchange part 11 Heat transfer tube 12 Outer cylinder 12a Shell 12b Header 13 Pipe 14 Flange 20 Bypass valve (distribution part)
21 passage 22 flap 22a shaft 22b plate 23 flange 30 gasket 40, 240, 340, 440 partition 50 bolt

Claims (7)

A plurality of stacked heat transfer tubes that exchange heat between a fluid introduced from the outside and a refrigerant flowing inside, and an outer cylinder that houses the plurality of stacked heat transfer tubes,
The outer cylinder is formed in a bottomed cylinder shape that is open at one end and closed at the other end,
The closed side of the outer cylinder changes the direction of the fluid that has flowed from some of the plurality of stacked heat transfer tubes to the other heat transfer tube of the plurality of stacked heat transfer tubes. To turn,
A U-turn heat exchanger,
A diversion part having a flap for adjusting the flow rate of the fluid flowing through the part of the heat transfer pipes of the heat exchange part,
Between the one end of the heat transfer tube and the flap, there is a partition portion that closes a gap formed when the flow is switched so that a fluid flows through the heat transfer portion of the heat exchange portion. Provided,
A U-turn heat exchanger characterized by that. The U-turn heat exchanger according to claim 1,
The partition is formed at an end of the heat transfer tube.
A U-turn heat exchanger characterized by that. The U-turn heat exchanger according to claim 2,
The partition is integrally formed at an end of the heat transfer tube.
A U-turn heat exchanger characterized by that. The U-turn heat exchanger according to claim 1,
The partition is formed on the flap.
A U-turn heat exchanger characterized by that. The U-turn heat exchanger according to claim 4,
A part of the partition portion is arranged so as to overlap the flap.
A U-turn heat exchanger characterized by that. The U-turn heat exchanger according to any one of claims 1 to 5,
The partition is formed by bending an end of the flap.
A U-turn heat exchanger characterized by that. The U-turn heat exchanger according to any one of claims 1 to 6,
The flap has a guide plate for guiding the flow of fluid,
A U-turn heat exchanger characterized by that.

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