JP2016160778A - Exhaust heat recovery equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide exhaust heat recovery equipment for suppressing the internal leakage of exhaust gas to flow behind a valve.SOLUTION: Exhaust heat recovery equipment 1 for allowing a variation in the flow amount of exhaust gas to be heat-exchanged according to an operation mode includes a valve 70 for setting the direction of the exhaust gas to flow into a heat exchange part 2 or a bypass part 3. The valve 70 has a valve shaft 75, an upstream side valve plate part 72 extending from the valve shaft 75 to the upstream side, and a downstream side valve plate part 73 extending from the valve shaft 75 to the downstream side. A boundary part 45 isolating the heat exchange part 2 and the bypass part 3 from each other has a first seat part 46 and a second seat part 47 opposing each other across the downstream side valve plate part 73.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an exhaust heat recovery device in which the flow rate of exhaust for exchanging heat according to an operation mode can be changed.

  Patent Document 1 discloses an exhaust heat recovery device that can be switched between an operation mode in which the flow direction of exhaust gas is directed toward the heat recovery chamber and an operation mode in which the flow direction of exhaust gas is directed toward the detour by the operation of the temperature sensitive valve. An exhaust heat recovery device) is disclosed.

  The temperature-sensitive valve includes a thermowax unit that operates according to temperature, a rotating shaft that is rotationally driven by the thermowax unit, and a plate-like flow path switching damper that is coupled to the rotating shaft.

  A partition wall is provided between the heat recovery chamber and the bypass, and the rotation shaft of the temperature-sensitive valve is disposed in the vicinity of the partition wall.

  In the operation mode in which the flow direction of the exhaust is directed to the heat recovery chamber side, the flow path switching damper of the temperature-sensitive valve is in a position to close the detour entrance, and the exhaust is transferred to the heat recovery chamber by the temperature-sensitive valve and the partition wall. Led. On the other hand, in the operation mode in which the flow direction of the exhaust is directed to the detour side, the flow path switching damper rotates and is switched to a position to close the inlet of the heat recovery chamber, so that the exhaust is detoured by the temperature sensitive valve and the partition wall. Led to.

JP 2010-229847 A

  However, in the exhaust heat recovery device described in Patent Document 1, since the rotation shaft of the temperature-sensitive valve is disposed in the vicinity of the partition wall, the outer periphery of the rotation shaft of the temperature-sensitive valve and the upstream end of the partition wall are arranged. There is a gap between them. For this reason, in each of the above operation modes, there is a problem that an internal leak occurs in which part of the exhaust flows through the gap to the back of the temperature-sensitive valve.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an exhaust heat recovery device in which internal leakage of exhaust gas flowing behind the valve can be suppressed.

  According to an aspect of the present invention, there is provided an exhaust heat recovery device in which the flow rate of exhaust gas for exchanging heat is changed according to an operation mode, wherein the exhaust gas introduced into the exhaust gas flow and the exhaust gas introduced from the diverter gas are heat exchanged. A heat exchanging part that bypasses the heat exchanging part, a valve that directs the flow direction of the exhaust gas that passes through the diverting part to the heat exchanging part or the bypass part, and a heat exchanging part And a collecting portion for guiding exhaust gas that has passed through the heat exchanging portion or the bypass portion, and the valve is configured to rotate in accordance with an operation mode, and a flow direction of the exhaust gas from the valve shaft. And an upstream valve plate portion extending upstream from the valve shaft and a downstream valve plate portion extending downstream from the valve shaft in the exhaust flow direction, and the boundary portion is opposed to the downstream valve plate portion. 1 seat and 2nd seat Exhaust heat recovery device is provided, characterized in that it comprises a part.

  According to the above aspect, the flow direction of the exhaust gas is switched to the heat exchange part or the bypass part by rotating the valve. At this time, the downstream valve plate portion that rotates about the valve shaft faces the first seat portion or the second seat portion, so that a gap generated between the valve and the boundary portion is suppressed to be small, and exhaust is reduced. Internal leakage that flows behind the valve is suppressed.

It is a perspective view showing an exhaust heat recovery device concerning a 1st embodiment of the present invention. It is a disassembled perspective view of an exhaust heat recovery device. FIG. 3 is a cross-sectional view of the exhaust heat recovery unit along the line III-III in FIG. 1. It is sectional drawing which shows the state in which the operation mode of the exhaust heat recovery device was switched. It is sectional drawing which shows the exhaust heat recovery device which concerns on 2nd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

<First Embodiment>
An exhaust heat recovery device 1 shown in FIG. 1 heats a medium by the heat of exhaust (fluid) during a warm-up operation of an engine (not shown) mounted on a vehicle.

  The medium is a coolant that circulates through the engine. During the warm-up operation, the engine is heated by the heat of the exhaust, so that the engine, the oil cooler, or other equipment after startup is warmed. For example, the medium may circulate through an air conditioner (not shown) and the vehicle may be heated.

  The exhaust heat recovery device 1 includes a flow dividing section 4 into which exhaust gas is introduced, a heat exchange section 2 in which exhaust gas guided from the flow distribution section 4 exchanges heat with a medium, and exhaust gas guided from the flow distribution section 4 passes through the heat exchange section 2. The bypass part 3 which flows by detouring and the gathering part 5 which guides the exhaust gas that has passed through the heat exchange part 2 or the bypass part 3 are provided.

  Exhaust gas discharged from the engine flows into the flow dividing section 4 as shown by an arrow A in FIG. 1, passes through the heat exchange section 2 or the bypass section 3 via the flow dividing section 4, and then gathers as shown by an arrow B It flows out from the part 5. O in the figure is the center line of the exhaust heat recovery device 1.

  As shown in FIG. 2, the heat exchanging unit 2 includes a plurality of flat tubes 32 and a box-shaped shell 36 that accommodates the tubes 32.

  As shown in FIG. 3, a heat exchange channel 31 extending in the direction of the center line O is formed inside the tube 32. Each tube 32 is arranged in a direction orthogonal to the center line O, and one end of each tube 32 is opened along with the inlet 33 (upstream end) of the heat exchange unit 2, and the other end is the outlet 34 (downstream) of the heat exchange unit 2. Open side by side. Exhaust gas flows in the direction of the center line O through the heat exchange flow path 31 in each tube 32.

  Inside the shell 36, a medium flow path 35 through which a medium (coolant) flows is formed. A tubular medium introduction portion 16 and a medium discharge portion 17 protrude outside the shell 36. Pipes (not shown) for guiding the medium are respectively connected to the medium introduction unit 16 and the medium discharge unit 17.

  The medium guided from the engine through a cooling passage (not shown) flows into the medium flow path 35 through the medium introducing portion 16 as indicated by an arrow C in FIG. Heat is exchanged with the exhaust in the flow process. The medium whose temperature has increased in the medium flow path 35 flows out of the medium discharge portion 17 as indicated by an arrow D, and is guided to the engine through the cooling passage.

  The shell 36 is formed in a box shape having a substantially rectangular cross-sectional shape. The shell 36 has four outer wall portions extending in a flat plate shape in the direction of the center line O. Of the four outer wall portions, a portion extending facing the bypass portion 3 constitutes a heat exchange portion boundary wall 36a of the boundary portion 45 as described later.

  The bypass unit 3 includes a cylindrical bypass pipe 30 that forms a bypass flow path 39. The bypass pipe 30 extends in the direction of the center line O, and is arranged in parallel with the tube 32 of the heat exchange unit 2 with respect to the exhaust flow direction.

  The inlet 37 (upstream end) of the bypass part 3 (bypass pipe 30) opens side by side in the left-right direction perpendicular to the center line O with respect to the inlet 33 of the heat exchange part 2 (shell 36). Similarly, the outlet 38 (downstream end) of the bypass unit 3 opens side by side in the left-right direction orthogonal to the center line O with respect to the outlet 34 of the heat exchange unit 2. The exhaust gas flows through the bypass channel 39 in the direction of the center line O.

  The bypass pipe 30 is formed in a cylindrical shape having a D-shaped cross section. Of course, the bypass pipe 30 may have other cross-sectional shapes such as a triangle. The bypass pipe 30 includes a flat plate-like bypass part boundary wall 30b extending opposite to the heat exchange part boundary wall 36a of the shell 36, a pair of side wall parts 30a extending orthogonally from both sides of the bypass part boundary wall 30b, and each side wall. And a curved wall portion 30c extending curvedly from the portion 30a.

  The diversion unit 4 includes a diversion pipe 6 (inlet side diffuser) that forms a diversion passage 29 for introducing exhaust gas, and a valve 70 that is accommodated in the diversion pipe 6. By rotating the valve 70 in the flow dividing pipe 6, the flow direction of the exhaust gas passing through the flow dividing section 4 is directed to the heat exchange section 2 or the bypass section 3. In the diversion unit 4, the flow rate ratio of the exhaust gas diverted to the heat exchange unit 2 and the bypass unit 3 is changed according to the angle at which the valve 70 rotates in the diversion pipe 6.

  As shown in FIG. 2, the tapered cylindrical branch pipe 6 is formed by joining a semi-tubular upper branch pipe section 6a and a semi-tubular lower branch pipe section 6b to each other. The branch channel 29 is formed so that its channel area gradually increases in the exhaust flow direction.

  The inlet 24 (upstream end) of the branch pipe 6 is connected to an exhaust pipe (not shown) extending from the engine via the flange 8. Exhaust gas discharged from the engine flows into the branch pipe 6 from the exhaust pipe as indicated by an arrow A.

  An inlet 33 of the heat exchange unit 2 and an inlet 37 of the bypass unit 3 are connected side by side to the outlet 26 (downstream end) of the branch pipe 6.

  The valve 70 includes a valve shaft 75 that is rotatably supported by the flow dividing pipe 6, and a valve plate 71 that is coupled to the valve shaft 75.

  The valve plate 71 is coupled to the valve shaft 75 via a plurality of screws (not shown). However, the present invention is not limited thereto, and the valve plate 71 may be formed integrally with the valve shaft 75.

  The valve shaft 75 is rotatably supported by the flow dividing pipe 6 by being inserted into the hole 12 of the flow dividing pipe 6. The valve shaft 75 is disposed so as to extend in the vertical direction perpendicular to the center line O.

  An actuator (not shown) such as a motor is connected to the valve shaft 75. The actuator rotationally drives the valve shaft 75 in response to a command from a controller (not shown). The rotation position of the valve 70 is arbitrarily switched between a heat exchange position for guiding exhaust gas to the heat exchanging unit 2 as shown in FIG. 3 and a bypass position for guiding exhaust gas to the bypass unit 3 as shown in FIG. It is done.

  The actuator is not limited to the above-described configuration, and a temperature sensitive material that operates according to the temperature of the medium may be used.

  As shown in FIGS. 3 and 4, the collecting portion 5 includes a tapered tubular collecting pipe 23 (outlet side diffuser) that forms a combined flow path 60 that guides exhaust gas. As shown in FIG. 2, the collecting tube 23 is formed by joining a semi-cylindrical upper collecting tube portion 23a and a semi-cylindrical lower collecting tube portion 23b to each other. The combined channel 60 is formed such that the channel area gradually decreases in the exhaust flow direction.

  An outlet 34 of the heat exchange part 2 and an outlet 38 of the bypass part 3 are connected to the inlet 52 (upstream end) of the collecting pipe 23 side by side in the left-right direction.

  An outlet 51 (downstream end) of the collecting pipe 23 is connected to an exhaust pipe (not shown) via the flange 25. Exhaust gas guided through the collecting pipe 23 flows into the exhaust pipe as indicated by an arrow B, and is discharged to the outside through the exhaust pipe.

  The exhaust heat recovery device 1 includes a boundary part 45 that separates the heat exchange part 2 and the bypass part 3. The boundary portion 45 includes a heat exchange portion boundary wall 36 a, a bypass portion boundary wall 30 b, an upstream heat insulator 41, and a downstream heat insulator 42.

  The bypass part boundary wall 30b of the bypass part 3 and the heat exchange part boundary wall 36a of the heat exchange part 2 are formed in a planar shape facing each other and extending parallel to the center line O.

  The upstream-side heat insulator 41 and the downstream-side heat insulator 42 are provided as isolation portions that provide a gap between the heat exchange portion boundary wall 36a and the bypass portion boundary wall 30b.

  The upstream heat insulator 41 and the downstream heat insulator 42 are formed of a heat insulating material having a lower thermal conductivity than the heat exchange section boundary wall 36a and the bypass section boundary wall 30b. As the heat insulating material, for example, a porous material surrounded by a metal layer and evacuated is used.

  In addition, it is not restricted to the structure mentioned above, As a separation part which provides a space | interval between the heat exchange part boundary wall 36a and the bypass part boundary wall 30b, heat conductivity equivalent to the heat exchange part boundary wall 36a and the bypass part boundary wall 30b It may be configured to be provided with a member having

  An air layer 9 is formed between the heat exchange section boundary wall 36 a, the bypass section boundary wall 30 b, the upstream heat insulator 41, and the downstream heat insulator 42. The upstream heat insulator 41, the downstream heat insulator 42, and the air layer 9 constitute a heat insulating layer that suppresses heat transfer between the bypass unit 3 and the heat exchange unit 2.

  The exhaust heat recovery device 1 includes a case 15 that covers the air layer 9. The air layer 9 is formed as a space blocked from the outside by being covered by the case 15.

  The semi-cylindrical case 15 has a cross-sectional shape along the outer shape of the heat exchange part 2 and the boundary part 45, and has both end parts 18 extending so as to sandwich the bypass part 3. Both end portions 18 of the case 15 are joined to the side wall portion 30 a of the bypass pipe 30.

  The valve 70 is arranged such that the valve shaft 75 has a predetermined distance upstream from the end of the boundary 45 in the exhaust flow direction.

  The valve plate 71 includes a coupling portion 74 coupled to the valve shaft 75, an upstream valve plate portion 72 extending upstream from the coupling portion 74, and a downstream valve plate portion 73 extending downstream from the coupling portion 74. Have. The distal end of the upstream side valve plate portion 72 is formed to be curved along the inner wall of the flow dividing pipe 6. The distal end of the downstream valve plate portion 73 is formed in a straight line extending in parallel with the valve shaft 75.

  A first seat portion 46 and a second seat portion 47 that are opposed to each other with a downstream side valve plate portion 73 that rotates about the valve shaft 75 being provided are provided at the end portion of the boundary portion 45.

  The first sheet portion 46 is formed at the end portion of the heat exchange portion boundary wall 36 a that faces the branch channel 29. The first seat portion 46 extends in parallel with the valve shaft 75 and is disposed so as to abut the tip of the downstream side valve plate portion 73.

  The second sheet portion 47 is formed at an end portion of the bypass portion boundary wall 30 b that faces the branch channel 29. The second seat portion 47 extends in parallel with the valve shaft 75 and is disposed so as to abut the tip of the downstream side valve plate portion 73.

  At the end of the boundary portion 45, a valve housing recess 48 facing the branch channel 29 is provided. The valve accommodating recess 48 accommodates the rotating downstream valve plate 73.

  The valve housing recess 48 is formed by the heat exchange portion boundary wall 36 a including the first seat portion 46, the bypass portion boundary wall 30 b including the second seat portion 47, and the end surface of the upstream heat insulator 41.

  The end surface of the upstream heat insulating body 41 forms a bottom wall portion of the valve accommodating recess 48. The upstream heat insulator 41 is offset with respect to the first seat portion 46 and the second seat portion 47 in a direction away from the valve shaft 75 (rightward in FIG. 3). Thus, the downstream valve plate 73 does not interfere with the upstream heat insulator 41 during the operation of rotating the valve 70.

  Next, the operation of the exhaust heat recovery device 1 will be described.

  Exhaust gas discharged from the engine flows to the heat exchanging unit 2 or the bypass unit 3 as the valve 70 rotates.

  In the heat recovery operation mode in which the exhaust heat recovery device 1 warms the medium by exhaust when the engine is cold, the actuator holds the valve 70 in the rotation position (heat exchange position) shown in FIG. 3 in response to a command from the controller. To do. Thereby, the bypass flow path 39 is closed with respect to the branch flow path 29, while the heat exchange flow path 31 is opened. As shown by arrows E, F, and G in FIG. 3, the exhaust gas is guided to pass through the branch channel 29, the heat exchange channel 31, and the combined channel 60, and performs heat exchange with the medium in the heat exchange unit 2. Thus, in the exhaust heat recovery device 1, the temperature of the medium rises as the medium absorbs the heat of the exhaust.

  In the heat recovery operation mode, as shown in FIG. 3, the valve 70 is inclined in the diverter pipe 6, the tip of the upstream valve plate portion 72 is in contact with the inner wall of the diverter tube 6, and the downstream valve plate portion 73 The front end abuts on the first sheet portion 46 of the boundary portion 45. Thereby, the clearance gap produced between the valve | bulb 70 and the inner wall or boundary part 45 of the shunt pipe 6 is restrained small. For this reason, internal leakage in which part of the exhaust gas flows between the valve 70 and the boundary portion 45 to the bypass flow path 39 is suppressed. As a result, in the exhaust heat recovery device 1, the heat quantity of the exhaust absorbed by the medium in the heat exchanging unit 2 is increased, and warming up of the engine or the like is promoted.

  When the engine is warmed up and the exhaust heat recovery device 1 does not need to circulate the exhaust gas to the heat exchanging section 2, it is switched to the non-recovery operation mode. In the non-recovery operation mode, the actuator rotates the valve 70 in accordance with a command from the controller to switch to the rotation position (bypass position) shown in FIG. Thereby, the heat exchange flow path 31 is closed with respect to the branch flow path 29 by the valve 70, while the bypass flow path 39 is opened. The exhaust gas is guided so as to pass through the diversion channel 29, the bypass channel 39, and the combined channel 60 as indicated by arrows I, J, and K in FIG. In this way, the exhaust gas bypasses the heat exchanging unit 2 to suppress the medium from being heated by the exhaust gas.

  In the non-recovery operation mode, as shown in FIG. 4, the valve 70 is inclined in the flow dividing pipe 6, the tip of the upstream valve plate portion 72 is in contact with the inner wall of the flow dividing pipe 6, and the downstream valve plate portion 73 The front end abuts on the second sheet portion 47 of the boundary portion 45. Thereby, the clearance gap produced between the valve | bulb 70 and the inner wall or boundary part 45 of the shunt pipe 6 is restrained small. For this reason, internal leakage in which part of the exhaust gas flows between the valve 70 and the boundary portion 45 to the heat exchange flow path 31 is suppressed. As a result, in the exhaust heat recovery device 1, the medium is sufficiently suppressed from being heated by the exhaust, and the warmed-up engine and the like are prevented from being heated by the medium.

  Next, effects of the first embodiment will be described.

  According to the present embodiment, the valve 70 has the downstream valve plate portion 73 extending downstream from the valve shaft 75, and the boundary portion 45 is opposed to the first valve seat so as to sandwich the rotating downstream valve plate portion 73. An exhaust heat recovery device 1 having a portion 46 and a second sheet portion 47 is provided.

  Based on the above configuration, as the valve 70 rotates about the valve shaft 75, the downstream valve plate portion 73 faces the first seat portion 46 or the second seat portion 47, thereby causing a boundary with the valve 70. A gap generated between the portions 45 is suppressed to be small. Thereby, the internal leakage through which the exhaust gas passes between the valve 70 and the boundary portion 45 and flows behind the valve 70 is suppressed. As a result, in the exhaust heat recovery device 1, the flow rate ratio of the exhaust gas divided into the heat exchange unit 2 and the bypass unit 3 is accurately changed according to the operation of the valve 70, and the temperature of the medium is adjusted with high accuracy.

  Further, according to the present embodiment, in the operation mode in which the valve 70 directs the flow direction of the exhaust toward the heat exchanging unit 2, the downstream side valve plate portion 73 contacts the first seat portion 46, and the valve 70 changes the flow direction of the exhaust. The exhaust heat recovery device 1 is provided in which the downstream valve plate portion 73 abuts against the second seat portion 47 in the operation mode directed to the bypass portion 3.

  Based on the above configuration, the downstream valve plate portion 73 that rotates around the valve shaft 75 is switched to a state in which the first seat portion 46 or the second seat portion 47 abuts according to the operation mode. Thereby, the clearance gap produced between the valve 70 and the boundary part 45 is suppressed small, and the internal leak of exhaust gas is fully suppressed.

  The exhaust heat recovery device 1 is not limited to the above-described configuration, and the first seat portion 46 or the second seat portion 47 faces the downstream side valve plate portion 73 with a preset small gap according to the operation mode. By doing so, the internal leakage of the exhaust gas may be sufficiently suppressed.

  Moreover, according to this embodiment, the 1st sheet | seat part 46 is formed in the heat exchange part boundary wall 36a which comprises the outer wall of the heat exchange part 2, and the 2nd sheet | seat part 47 comprises the bypass part which comprises the outer wall of the bypass part 3. An exhaust heat recovery device 1 formed on the boundary wall 30b is provided.

  Based on the above configuration, it is not necessary to provide a separate member from the heat exchanging unit 2 and the bypass unit 3 to form the first sheet unit 46 and the second sheet unit 47, and the structure of the exhaust heat recovery device 1 is complicated. Is suppressed.

  Moreover, according to this embodiment, the boundary part 45 is interposed between the heat exchange part boundary wall 36a and the bypass part boundary wall 30b, and the exhaust heat recovery device which has the upstream heat insulating body 41 which insulates between both. 1 is provided.

  Based on the above configuration, the heat exchanger 2 and the bypass 3 are insulated from each other by the upstream heat insulator 41 interposed between the heat exchanger boundary wall 36a and the bypass boundary wall 30b. In the heat recovery operation mode, the heat exchanging efficiency of the heat exchanging unit 2 is increased by the upstream heat insulator 41, and warming up of the engine or the like is promoted. On the other hand, in the non-recovery operation mode, heat transfer from the bypass unit 3 to the heat exchange unit 2 is suppressed by the upstream heat insulator 41. As a result, the medium is sufficiently prevented from being heated by the exhaust, and the engine after the warm-up is prevented from being heated.

  Further, according to the present embodiment, the exhaust heat in which the valve housing recess 48 for housing the downstream valve plate portion 73 is formed between the upstream heat insulator 41, the heat exchange portion boundary wall 36a, and the bypass portion boundary wall 30b. A collector 1 is provided.

  Based on the above configuration, the downstream valve plate portion 73 is rotated by the valve housing recess 48 to prevent the downstream valve plate portion 73 from interfering with the upstream heat insulator 41 and the like.

  In addition, according to the present embodiment, the boundary portion 45 includes the air layer 9 formed between the upstream heat insulator 41, the heat exchange portion boundary wall 36a, and the bypass portion boundary wall 30b, and the air layer 9 as the outside. There is provided an exhaust heat recovery device 1 having a case 15 that covers it so as to block it.

  Based on the above configuration, the air layer 9 sealed to the outside is formed between the case 15, the heat exchange unit 2, and the bypass unit 3, so that the valve 70 directs the flow direction of the exhaust toward the heat exchange unit 2. In the operation mode, heat radiation from the heat exchanging unit 2 to the outside is suppressed, and the temperature of the exhaust gas and the medium in the heat exchanging unit 2 can increase the heat exchange efficiency.

Second Embodiment
Next, a second embodiment of the present invention will be described with reference to FIG. Below, it demonstrates centering on a different point from the said 1st Embodiment, the same code | symbol is attached | subjected to the structure same as the exhaust heat recovery device 1 of the said 1st Embodiment, and description is abbreviate | omitted.

  The exhaust heat recovery device 1 according to the first embodiment includes a case 15 that covers the air layer 9 of the boundary portion 45 so as to be blocked from the outside. On the other hand, the exhaust heat recovery device 100 according to the second embodiment does not include the case 15 and is configured such that the air layer 109 of the boundary portion 145 communicates with the outside.

  The air layer 109 is formed between the heat exchange part boundary wall 36 a, the bypass part boundary wall 30 b, the upstream heat insulator 41, and the downstream heat insulator 42.

  According to this embodiment, the air layer 109 communicating with the outside is formed between the heat exchange unit 2 and the bypass unit 3, and outside air is taken into the air layer 109. Thus, in the non-recovery operation mode, heat release from the bypass unit 3 to the outside air of the air layer 109 is promoted, and heat transfer from the bypass unit 3 to the heat exchange unit 2 is suppressed by the air layer 109. As a result, the medium is sufficiently prevented from being heated by the exhaust, and the engine after the warm-up is prevented from being heated.

  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.

  The present invention is suitable as an exhaust heat recovery device mounted on a vehicle, but can also be applied to a heat exchanger used other than the vehicle.

DESCRIPTION OF SYMBOLS 1,100 Exhaust heat recovery device 2 Heat exchange part 3 Bypass part 4 Dividing part 5 Collecting part 9,109 Air layer 15 Case 30b Bypass part boundary wall 36a Heat exchange part boundary wall 41 Upstream heat insulator 45, 145 Boundary part 46th 1 seat portion 47 second seat portion 48 valve housing recess 70 valve 72 upstream valve plate portion 73 downstream valve plate portion 75 valve shaft

Claims (6)

An exhaust heat recovery device in which the flow rate of the exhaust gas that exchanges heat according to the operation mode can be changed,
A diversion part into which exhaust is introduced;
A heat exchanging unit for exchanging heat with the exhaust led from the flow dividing unit;
A bypass section in which exhaust gas guided from the branch section flows around the heat exchange section;
A valve for directing the flow direction of the exhaust gas passing through the diversion part to the heat exchange part or the bypass part;
A boundary part separating the heat exchange part and the bypass part;
An assembly that guides the exhaust gas that has passed through the heat exchange unit or the bypass unit,
The valve is
A valve shaft that rotates according to the operating mode;
An upstream valve plate extending upstream from the valve shaft in the exhaust flow direction;
A downstream valve plate extending downstream from the valve shaft in the exhaust flow direction,
The exhaust heat recovery device according to claim 1, wherein the boundary portion includes a first seat portion and a second seat portion facing each other with the downstream valve plate portion interposed therebetween. The exhaust heat recovery device according to claim 1,
The first seat portion contacts the downstream valve plate portion in an operation mode in which the valve directs the flow direction of exhaust toward the heat exchange portion,
The exhaust heat recovery device according to claim 2, wherein the second seat portion contacts the downstream valve plate portion in an operation mode in which the valve directs the flow direction of exhaust toward the bypass portion. The exhaust heat recovery device according to claim 1 or 2,
The boundary is
A heat exchange section boundary wall forming an outer wall of the heat exchange section;
A bypass portion boundary wall that forms an outer wall of the bypass portion, and
The first sheet portion is formed at an end portion of the heat exchange portion boundary wall facing the flow dividing portion,
The exhaust heat recovery device according to claim 2, wherein the second sheet portion is formed at an end portion of the bypass portion boundary wall facing the flow dividing portion. The exhaust heat recovery device according to claim 3,
The exhaust heat recovery device according to claim 1, wherein the boundary portion further includes a heat insulator interposed between the heat exchange portion boundary wall and the bypass portion boundary wall. An exhaust heat recovery device according to claim 4,
The boundary is
An air layer formed between the heat exchange section boundary wall and the bypass section boundary wall;
An exhaust heat recovery device further comprising: a case that covers the air layer so as to be blocked from the outside. An exhaust heat recovery device according to claim 4,
The exhaust heat recovery device according to claim 1, wherein the boundary portion further includes an air layer formed between the heat exchange portion boundary wall and the bypass portion boundary wall, and the air layer communicates with the outside.

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