Exhaust gas heat recovery device

Abstract

An exhaust gas heat recovery device (1) is provided with: a first flow path member (10) having a first flow path through which exhaust gas flows; a second flow path member (20) that is adjacent to the first flow path member (10), has a heat exchange unit (30), and has a second flow path; and a valve mechanism (40) that opens and closes the first flow path and blocks or blocks the flow of the exhaust gas from the second flow path. The valve mechanism (40) is provided with: a valve body (43) that closes the first flow path in a heat recovery state in which the first flow path is closed; and a shutter section (42) that blocks or blocks the flow of the exhaust gas from the second flow path in a heat non-recovery state in which the first flow path is opened, the first flow path member (10) has a first rising section (17) that rises toward the inside of the first flow path, and the tip (43a) of the valve body (43) abuts or approaches the first rising section (17) in a heat recovery state of the valve body (43).

Description

Technical Field

[0001] This invention relates to an exhaust heat recovery device. Background Technology

[0002] JP2021-188567A discloses a waste gas heat recovery device comprising: a first flow path component having a first flow path for waste gas to flow through; a second flow path component being disposed adjacent to the first flow path and having a second flow path bypassing (bypassing) the first flow path; and a heat exchange section for exchanging heat between the waste gas and a refrigerant.

[0003] The waste gas heat recovery device described in JP2021-188567A includes a valve mechanism for switching the flow path of waste gas to a first flow path or a second flow path. The valve mechanism includes: a butterfly valve that opens and closes the first flow path under the action of a rotating shaft orthogonal to the flow direction of the waste gas in the first flow path; and a gate portion that closes the outlet of the second flow path, which serves as a bypass flow path, when the butterfly valve opens the first flow path, and opens the outlet when the butterfly valve closes the first flow path. Summary of the Invention

[0004] In the waste gas heat recovery device disclosed in JP2021-188567A, it is envisioned that the outlet is sealed by the surface contact between the outer peripheral wall of the cylindrical gate portion and the inner wall of the first flow path component. However, to achieve this, the dimensional relationship between the two needs to be precisely matched. That is, if the cylindrical shape of the gate portion is larger than the inner wall (inner periphery) of the first flow path component due to the tolerance relationship between the two, the front end of the gate portion will make corner contact with the inner wall of the first flow path component.

[0005] According to one aspect of the present invention, an exhaust gas heat recovery device for recovering heat from exhaust gas discharged from an engine by heat exchange with a fluid comprises: a first flow path component having a first flow path for exhaust gas to flow through; a second flow path component disposed adjacent to the first flow path component, having a second flow path internally bypassing a portion of the first flow path, and having a heat exchange section for heat exchange between the exhaust gas flowing in the second flow path and the fluid; and a valve mechanism disposed in the first flow path, the first flow path component having: an outlet for exhaust gas to flow out from the first flow path to the second flow path; an inlet for exhaust gas to flow in from the second flow path to the first flow path; and a first upright portion located upstream of the inlet portion in the first flow path, and erected inward of the first flow path in a direction orthogonal to the flow direction of the exhaust gas, the valve mechanism being... The valve mechanism comprises: a rotating shaft portion; a valve body that rotates with the rotating shaft portion and is used to close or open the first flow path; and a gate portion that rotates with the rotating shaft portion and is used to close or obstruct the flow of waste gas from the inlet. In a heat recovery state, the valve body of the valve mechanism closes the first flow path, and the gate portion opens the flow of waste gas from the inlet. In a non-heat recovery state, the valve body of the valve mechanism opens the first flow path, and the gate portion closes or obstructs the flow of waste gas from the inlet. In the non-heat recovery state, a gap is formed in the separation direction between the inlet and the gate portion. The first upright portion is formed such that its height in the height direction from the outside to the inside of the first flow path is greater than the gap. The front end of the gate portion abuts against or approaches the first upright portion in the non-heat recovery state.

[0006] According to the waste gas heat recovery device of the present invention, in the heat recovery state, it can fully realize the closure of the inlet or the obstruction of the waste gas flow, while preventing the front end of the gate and the inner wall of the first flow path component from angular contact. Attached Figure Description

[0007] Figure 1 This is a perspective view illustrating the waste gas heat recovery device according to the first embodiment of the present invention.

[0008] Figure 2 A front view showing a portion of the waste gas heat recovery device according to the first embodiment.

[0009] Figure 3 This is a side view, taken from the upstream side of the first flow path, illustrating the heat recovery state of the waste gas heat recovery device according to the first embodiment.

[0010] Figure 4This is a perspective view illustrating the valve mechanism of the waste gas heat recovery device according to the first embodiment.

[0011] Figure 5 A front view showing a portion of the waste gas heat recovery device according to the first embodiment.

[0012] Figure 6 This is a side view, taken from the upstream side of the first flow path, illustrating the non-recovery state of the waste gas heat recovery device according to the first embodiment.

[0013] Figure 7 A front view showing a portion of the waste gas heat recovery device according to the second embodiment.

[0014] Figure 8 A front view showing a portion of the waste gas heat recovery device 2 according to the second embodiment. Detailed Implementation

[0015] [First Implementation Method]

[0016] Hereinafter, with reference to the accompanying drawings, the waste gas heat recovery device 1 according to the first embodiment of the present invention will be described.

[0017] Figure 1 This is a perspective view illustrating the waste gas heat recovery device 1 according to the first embodiment of the present invention. Figure 2 A front view showing a portion of the waste gas heat recovery unit 1 being removed. Furthermore, Figure 3 To observe from the upstream side of the first flow path 14 Figure 2 The side view of the waste gas heat recovery device 1 in the heat recovery state.

[0018] like Figure 1 As shown, the waste gas heat recovery device 1 includes: a first flow path component 10, a second flow path component 20, and a heat exchange section 30.

[0019] The first flow path component 10 has a body portion 11, a first inflow portion 12, and a first outflow portion 13. The body portion 11 has a hollow structure, and a first flow path 14 for the flow of exhaust gas is formed inside the body portion 11.

[0020] The first inlet 12 is an opening on one side of the main body 11 and is connected to the flow path of exhaust gas from the engine. The first outlet 13 is an opening on the other side of the main body 11 and is connected to the flow path of exhaust gas. In the exhaust gas flow, the first inlet 12 is located upstream of the first outlet 13.

[0021] The main body 11 is formed with a structure that supplies exhaust gas from the first flow path 14 to the second flow path 24 (see...). Figure 2The first upstream opening 15 of the outlet and the first downstream opening 16 of the inlet for the flow of exhaust gas from the second flow path 24 to the first flow path 14.

[0022] The second flow path component 20 is disposed adjacent to the first flow path component 10. The second flow path component 20 has: a body portion 21, a second upstream side opening portion 22, and a second downstream side opening portion 23.

[0023] The main body 21 has a hollow structure, and a second flow path 24 is formed inside the main body 21 for the flow of exhaust gas to bypass a part of the first flow path 14.

[0024] The second upstream opening 22 is located upstream of the second flow path 24 and collects the exhaust gas bypassing a portion of the first flow path 14 into the interior of the main body 21. The second downstream opening 23 allows the exhaust gas flowing through the interior of the main body 21 to flow into the first flow path 14.

[0025] The second upstream opening 22 is connected to the first upstream opening 15 formed in the first flow path component 10 via the first connecting portion 25. Furthermore, the second downstream opening 23 is connected to the first downstream opening 16 formed in the first flow path component 10 via the second connecting portion 26.

[0026] The inner side of the first connecting portion 25, the interior of the second flow path component 20, and the inner side of the second connecting portion 26 constitute the second flow path 24.

[0027] The first flow path component 10 and the second flow path component 20 described above allow exhaust gas to bypass the first flow path 14 and pass through the first connecting portion 25 to the second flow path component 20. Furthermore, exhaust gas flowing through the second flow path component 20 can flow into the first flow path 14 via the second connecting portion 26.

[0028] The second flow path component 20 includes a heat exchange section 30. The heat exchange section 30 has a refrigerant inlet section 31, a heat exchange section body 32, and a refrigerant outlet section 33, and is supplied with cooling water, which is the refrigerant. The heat exchange section 30 performs heat exchange between the exhaust gas and the refrigerant flowing in the second flow path 24.

[0029] The refrigerant inlet 31 is a hollow tube-shaped portion that connects the flow path (not shown) for supplying cooling water before cooling the engine to the interior of the heat exchanger body 32. The refrigerant inlet 31 allows cooling water, which is the refrigerant, supplied from the aforementioned flow path, to flow into the interior of the heat exchanger body 32.

[0030] The refrigerant outlet 33 is a hollow tube-shaped portion that connects the interior of the heat exchanger body 32 to the flow path (not shown) that supplies cooling water to the engine. The refrigerant inlet 31 allows the cooling water flowing through the interior of the heat exchanger body 32 to flow out through the aforementioned flow path.

[0031] When exhaust gas flows within the portion of the body 21 of the second flow path component 20 surrounded by the heat exchange section body 32 (the portion of the second flow path 24 surrounded by the heat exchange section body 32), the heat exchange section 30 can perform heat exchange between the exhaust gas and the cooling water flowing inside the heat exchange section body 32, transferring the heat of the exhaust gas to the cooling water and recovering that heat. Furthermore, the state in which the valve mechanism 40 closes the first flow path 14 and the exhaust gas flows through the second flow path 24 for this heat exchange, as described later, is called the heat recovery state. On the other hand, the state in which the valve mechanism 40 opens the first flow path 14 and the exhaust gas does not flow through the second flow path 24 is called the heat non-recovery state.

[0032] In a first embodiment, the first flow path component 10 has a first upright portion 17 that stands upright toward the inside of the first flow path 14. The first upright portion 17 is located upstream of the first downstream opening 16 in the first flow path 14. Alternatively, the first upright portion 17 is disposed on the inner surface of the first flow path component 10 between the first upstream opening 15 and the first downstream opening 16. Furthermore, the first upright portion 17 is continuously formed in a direction orthogonal to the flow direction of the exhaust gas in the first downstream opening 16.

[0033] The first flow path component 10 has a second upright portion 18 that stands upright toward the inside of the first flow path 14 on its inner surface. The second upright portion 18 is disposed on the inner surface of the first flow path component 10 facing the surface on which the first upright portion 17 is formed. In the heat recovery state, the second upright portion 18 is located in the valve body 43 of the valve mechanism 40. Figure 4 The upstream side of the exhaust gas. In addition, the second upright portion 18 is continuously formed in a direction orthogonal to the flow direction of the exhaust gas.

[0034] In this embodiment, the first erected portion 17 is formed such that, in the non-heat recovery state ( Figure 5 Under these conditions, the height h1 from the inner surface of the first flow path component 10 is greater than the gap d1 generated in the separation direction between the first downstream opening 16 and the valve mechanism 40 (gate portion 42). Furthermore, the second upright portion 18 is formed such that, in the heat recovery state of the valve mechanism 40 ( Figure 2 Under these conditions, the height h2 from the inner surface of the first flow path component 10 is greater than the gap d2 in the separation direction between the inner surface of the first flow path component 10 and the valve mechanism 40 (valve body 43).

[0035] like Figure 2As shown, the waste gas heat recovery device 1 has a valve mechanism 40 inside the first flow path component 10.

[0036] Figure 4 For illustrative purposes Figure 1 A perspective view of the valve mechanism 40 of the waste gas heat recovery device 1 shown.

[0037] The valve mechanism 40 includes: a butterfly valve 41 for opening and closing the first flow path 14; a gate portion 42 for intercepting or blocking exhaust gas flowing from the second flow path 24 into the first flow path 14; and a valve body 43 for opening and closing the first flow path 14.

[0038] The valve body 43 is connected to a rotating shaft 44 and is supported rotatably within the first flow path 14. The rotating shaft 44 is connected to a drive shaft of an actuator, which is a drive unit (not shown).

[0039] The valve body 43 in the butterfly valve 41 is a plate-shaped component that can close the length and width of the first flow path 14. The valve body 43 can switch the opening or closing of the first flow path 14 by the rotation of the rotating shaft 44.

[0040] A gate portion 42 is provided on the valve body 43. The gate portion 42 has a plate-shaped gate body portion 42a and a pair of connecting portions 42b. The gate body portion 42a closes the first downstream opening 16 in the non-heat recovery state and opens the first downstream opening 16 in the non-heat recovery state.

[0041] The connecting part 42b supports the gate body part 42a in such a way that the gate body part 42a and the valve body 43 are kept at a distance that prevents the gate body part 42a from contacting the inner wall part (first downstream opening 16) of the first flow path component 10 and can close the first downstream opening 16.

[0042] The gate portion 42 has a protrusion 45 protruding outward in the direction of the rotation radius of the rotating valve mechanism 40. The surface of the protrusion 45 is formed as a curved surface, which is present in the non-heat recovery state. Figure 5 and Figure 6 When the protrusion 45 abuts against or approaches the inner surface of the first flow path component 10 on the downstream side of the first downstream side opening 16 in the direction of exhaust gas flow.

[0043] In the non-heat recovery state, the configuration is such that the front end 42e (end face) of the gate portion 42 on the upstream side in the direction of exhaust gas flow abuts or approaches the first erect portion 17.

[0044] <Valve mechanism operation and exhaust gas flow>

[0045] Next, the operation of the valve mechanism 40 and the flow of waste gas in the waste gas heat recovery device 1 of the first embodiment will be explained.

[0046] Figure 5 A front view showing a portion of the waste gas heat recovery unit 1 being removed. Additionally, Figure 6 To observe from the upstream side of the first flow path 14 Figure 5 The side view of the waste gas heat recovery device 1 in the non-recovery state.

[0047] The valve mechanism 40 in the waste gas heat recovery device 1 can be in the heat recovery state ( Figure 2 and Figure 3 ) and heat non-recovery state ( Figure 5 and Figure 6 The flow path 14 is switched between the two states: the heat recovery state is when the first downstream opening 16 is opened through the gate 42 while the first flow path 14 is closed through the butterfly valve 41; the heat non-recovery state is when the first downstream opening 16 is closed through the gate 42 while the first flow path 14 is opened through the butterfly valve 41.

[0048] In the first embodiment, such as Figure 5 and Figure 6 As shown, if the valve mechanism 40 is positioned such that the main surface of the valve body 43 of the valve mechanism 40 is aligned with the direction of exhaust gas flow (see...) Figure 5 When the arrow in the diagram rotates in a parallel manner to enter a non-recovery state, the front end 42e of the gate portion 42 abuts against the downstream surface of the first upright portion 17 in the direction of exhaust gas flow, and the protrusion 45 of the gate portion 42 abuts against the inner surface of the first flow path member 10 on the downstream side of the first downstream opening 16 in the direction of exhaust gas flow. Alternatively, in the non-recovery state, the front end 42e may abut against the first upright portion 17, and the protrusion 45 may approach the inner surface of the first flow path member 10. Furthermore, in the non-recovery state, the front end 42e may approach the first upright portion 17, and the protrusion 45 may abut against the inner surface of the first flow path member 10. In the non-recovery state, the front end 42e may abut against the first upright portion 17, and the protrusion 45 may also abut against the inner surface of the first flow path member 10. Here, "approaching" means being in a state of being opposite each other with a slight gap.

[0049] In this state, the exhaust gas flows from the first inlet 12 into the first flow path component 10, flows through the first flow path 14 formed inside the first flow path component 10, and flows out from the first outlet 13.

[0050] On the other hand, the valve mechanism 40 rotates to switch to the heat recovery state, causing the end 43a of the valve body 43 located upstream in the flow direction (in the non-heat recovery state) to rotate towards the first upright portion 17, while the end 43b of the valve body 43 located downstream in the flow direction rotates towards the second upright portion 18, so that the main surface of the valve body 43 of the valve mechanism 40 is orthogonal to the flow direction of the exhaust gas. Furthermore, the second upright portion 18 will be described in detail later.

[0051] like Figure 2 and Figure 3 As shown, in the heat recovery state, the upstream surface of the first upright portion 17 in the flow direction abuts against the downstream surface of the end portion 43a of the valve body 43 in the flow direction. Furthermore, the downstream surface of the second upright portion 18 in the flow direction abuts against the upstream surface of the end portion 43b of the valve body 43 in the flow direction.

[0052] In this state, if exhaust gas flows from the first inlet 12 into the first flow path component 10, the exhaust gas remains in the space S formed by the valve body 43 and the first flow path component 10, and flows into the second flow path 24 from the first upstream opening 15 (see...). Figure 2 (The arrow in the image).

[0053] In the heat recovery state, the surface of the upstream side of the first upright portion 17 may abut against the surface of the downstream side of the end 43a of the valve body 43, or the surface of the downstream side of the second upright portion 18 may abut against the surface of the upstream side of the end 43b of the valve body 43.

[0054] The exhaust gas flows through the second flow path 24 inside the second flow path component 20 and exchanges heat with the refrigerant flowing in the heat exchange section 30. After passing through the second flow path 24, the exhaust gas flows back to the first flow path 14 from the first downstream opening 16, and flows through the first flow path and out from the first outlet 13.

[0055] <Effects>

[0056] The waste gas heat recovery device 1 according to the first embodiment includes: a first flow path component 10, which has a first flow path 14 for waste gas to flow through it; a second flow path component 20, which is disposed adjacent to the first flow path component 10, and has a second flow path 24 that bypasses a part of the first flow path 14, and has a heat exchange section 30 for heat exchange between the waste gas flowing through the second flow path 24 and the refrigerant; and a valve mechanism 40, which is disposed in the first flow path component 10, and has a butterfly valve 41 for opening and closing the first flow path 14 and a gate section 42 for intercepting or blocking the flow of waste gas from the second flow path 24.

[0057] The first flow path component 10 has a first upstream opening 15 as an outlet for exhaust gas to flow out from the first flow path 14 to the second flow path 24 and a first downstream opening 16 as an inlet for exhaust gas to flow in from the second flow path 24 to the first flow path 14.

[0058] The valve mechanism 40 is configured to switch between a heat recovery state and a heat non-recovery state by rotating a rotating shaft 44 orthogonal to the flow direction of the exhaust gas in the first flow path 14. As described above, in the heat non-recovery state, the first downstream opening 16 is closed by the gate 42 while the first flow path 14 is opened by the butterfly valve 41. In the heat recovery state, the first downstream opening 16 is opened by the gate 42 while the first flow path 14 is closed by the butterfly valve 41.

[0059] The first flow path component 10 has a first upright portion 17 erected towards the inside of the first flow path 14 in a direction perpendicular to the flow direction of the exhaust gas (from the outside to the inside of the first flow path 14). The first upright portion 17 is located upstream of the first downstream side opening 16 in the first flow path 14. Furthermore, in the direction from the outside to the inside of the first flow path 14, the first upright portion 17 is formed to be larger than the gap d1 generated in the separation direction between the first downstream side opening 16 and the gate portion 42 for closing the first downstream side opening 16 in the non-heat recovery state.

[0060] Therefore, the first upright portion 17 can block the gap d1 generated in the separation direction between the first downstream opening 16 and the gate portion 42 in the non-heat recovery state. Here, if the exhaust gas flows in the first flow path 14, it is easy for the exhaust gas to be drawn into the second flow path 24 at the first downstream opening 16 under the action of this flow. However, in the exhaust gas heat recovery device 1, although there is a gap between the gate portion 42 and the first downstream opening 16, the formation of the first upright portion 17 suppresses the intake of such exhaust gas. As a result, it is possible to prevent the exhaust gas from flowing into the second flow path 24 at the first upstream opening 15.

[0061] Therefore, it is possible to prevent the flow of exhaust gas into the heat exchange section 30 when heat recovery from the exhaust gas is not required, thus preventing a decrease in exhaust gas discharge efficiency.

[0062] In conventional waste gas heat recovery devices, the second flow path is closed while the first flow path is opened by making the main surface of the cylindrical gate portion into surface contact with the inner wall of the first flow path component. However, in this structure, if there is an error between the dimensions of the gate portion and the dimensions of the inner wall (inner circumference) of the first flow path component, an interference angular contact will occur between a part of the gate portion and the inner wall of the first flow path component.

[0063] On the other hand, the exhaust heat recovery device 1 includes a first upright portion 17 and forms the aforementioned gap d1. Therefore, even without strictly designing the dimensions or positioning of the valve mechanism 40 and the first flow path component 10, the risk of contact between the inner surfaces of the valve mechanism 40 and the first flow path component 10 due to the rotational movement of the valve mechanism 40 can be avoided. According to the exhaust heat recovery device 1, interference angular contact between a portion of the gate portion and the inner wall of the first flow path component can be prevented. Furthermore, according to the exhaust heat recovery device 1, in the non-heat recovery state of the valve mechanism 40, sufficient interception or obstruction of the airflow from the second flow path 24 at the first downstream opening 16 can be achieved.

[0064] The first flow path component 10 has a second upright portion 18 on its inner surface opposite to the first upright portion 17, which is erected in a direction perpendicular to the flow direction of the exhaust gas toward the inner side of the first flow path 14.

[0065] The second upright portion 18 is formed to be larger than the gap d2 between the inner surface of the first flow path component 10 and the butterfly valve 41 in the separation direction when the valve mechanism 40 is in the heat recovery state, and is formed on the downstream side of the butterfly valve 41 when the valve mechanism 40 is in the heat recovery state.

[0066] In the heat recovery state of the valve mechanism 40, the second upright part 18 can block the gap d2 between the inner surface of the first flow path component 10 and the butterfly valve 41 in the separation direction from the downstream side.

[0067] Therefore, in the heat recovery state where the first downstream opening 16 is opened by the gate section 42 and the first flow path 14 is closed by the butterfly valve 41, it is possible to prevent waste gas from flowing into the first flow path 14.

[0068] Therefore, the waste gas heat recovery device 1 can suppress the leakage of waste gas into the first flow path 14 when heat needs to be recovered from the waste gas, thereby preventing a decrease in heat recovery efficiency.

[0069] In the heat recovery state of the waste gas heat recovery device 1 according to the first embodiment, the downstream surface of the end of the valve body 43 of the valve mechanism 40 in the flow direction abuts against the upstream surface of the first upright portion 17 in the flow direction. Furthermore, the upstream surface of the end of the valve body 43 in the flow direction abuts against the downstream surface of the second upright portion 18 in the flow direction.

[0070] Thus, the first lifting part 17 and the second lifting part 18 help to position the butterfly valve 41 in the heat recovery state of the valve mechanism 40.

[0071] Therefore, it enhances the effect of preventing the leakage of waste gas into the first flow path 14 when heat needs to be recovered from the waste gas, thus preventing a decrease in heat recovery efficiency.

[0072] In addition, as long as the valve mechanism 40 comes into contact with either the first upright part 17 or the second upright part 18, the positioning effect of the butterfly valve 41 in the heat recovery state of the valve mechanism 40 can be obtained.

[0073] The gate portion 42 has a protrusion 45 that protrudes outward in the direction of the rotation radius of the rotating valve mechanism 40. In the non-heat recovery state of the valve mechanism 40, the protrusion 45 abuts against the inner surface of the first flow path member 10 on the downstream side of the first downstream side opening 16 in the direction of exhaust gas flow.

[0074] The end of the valve mechanism 40 on the upstream side of the exhaust gas flow direction moves first when the valve mechanism 40 rotates, making it easy to come into contact with the inner surface of the first flow path member 10. In contrast, according to the exhaust gas heat recovery device 1, the gate portion 42 has a protrusion 45. Therefore, even if the gap between the end of the valve mechanism 40 on the upstream side of the exhaust gas flow direction and the inner surface of the first flow path member 10 is designed to allow for contact avoidance, the end of the valve mechanism 40 on the downstream side of the exhaust gas flow direction will still abut against the protrusion 45. Thus, the gate portion 42 is positioned when the valve mechanism 40 is not in a heat recovery state. In addition, since the protrusion 45 contacts the inner surface of the first flow path member 10 from an obtuse angle and the surface of the protrusion 45 is curved, it is less likely to be chipped (cut into the inner surface).

[0075] [Second Implementation]

[0076] Next, with reference to the accompanying drawings, the waste gas heat recovery device 2 according to the second embodiment of the present invention will be described. In the second embodiment, components having the same function as those in the first embodiment are labeled with the same reference numerals, and their detailed descriptions are omitted.

[0077] Figure 7 and Figure 8 A front view showing a portion of the waste gas heat recovery device 2 according to the second embodiment. Figure 7 The condition of valve mechanism 40 in the waste gas heat recovery device 2 being in heat recovery mode will be explained. Figure 8 The situation where valve mechanism 40 is in a non-heat recovery state is explained.

[0078] In the second embodiment, the first upright portion 17 and the second upright portion 18 in the first embodiment are formed at the downstream end of the inner component 70 in the direction of exhaust gas flow.

[0079] That is, the waste gas heat recovery device 2 has an inner component 50 inside the first flow path component 10, which covers at least a portion of the inner surface of the first flow path component 10. The inner component 50 is integrally formed with a first upright portion 51 and a second upright portion 52 that bends toward the inside of the first flow path 14.

[0080] In the second embodiment, the first erected portion 51 is formed in the non-heat recovery state of the valve mechanism 40 ( Figure 8 The height H1 of the lower part from the inner surface of the first flow path component 10 is greater than the gap D1 generated in the separation direction between the first downstream opening 16 and the valve mechanism 40 (gate part 42). Furthermore, the second upright part 52 is formed in the heat recovery state of the valve mechanism 40 ( Figure 7 The height H2 of the lower part of the first flow path component 10 is greater than the gap D2 between the inner surface of the first flow path component 10 and the valve mechanism 40 (valve body 43) in the separation direction.

[0081] In the waste gas heat recovery device 2, if the valve mechanism 40 is in heat recovery mode, the upstream surface of the first upright portion 51 in the flow direction abuts against the downstream surface of the end portion 43a of the valve body 43 in the flow direction. Furthermore, the downstream surface of the second upright portion 52 in the flow direction abuts against the upstream surface of the end portion 43b of the valve body 43 in the flow direction.

[0082] Thus, the first lifting part 51 and the second lifting part 52 help to position the butterfly valve 41 in the heat recovery state of the valve mechanism 40.

[0083] Therefore, the waste gas heat recovery device 2 enhances the effect of preventing waste gas leakage into the first flow path 14 when heat needs to be recovered from the waste gas, thus preventing a decrease in heat recovery efficiency.

[0084] Furthermore, in the waste gas heat recovery device 2 according to the second embodiment, the waste gas comes into contact with the inner member 50 provided inside the first flow path member 10. Therefore, the thermal stress difference generated on the first flow path member 10 due to the heat of the waste gas can be reduced. Therefore, the heat resistance of the waste gas heat recovery device 2 can be improved.

[0085] [Other Implementation Methods]

[0086] The above describes the embodiments of the present invention. However, the above embodiments are only a part of the application examples of the present invention, and their purpose is not to limit the technical scope of the present invention to the specific structure of the above embodiments.

[0087] In the first embodiment, the fluid used for cooling the exhaust gas is not limited to cooling water, but may also be a medium such as a liquid or gas suitable for heat exchange.

[0088] In this embodiment, the valve mechanism 40 is a structure in which a pair of connecting portions 42b support both ends of the gate body portion 42a. Alternatively, for example, one connecting portion 42b may be provided at the center of the gate body portion 42a. Furthermore, it may be a so-called louver structure in which multiple connecting portions 42b are arranged in parallel.

[0089] In the waste gas heat recovery device 2 according to the second embodiment, the inner component 50 disposed inside the first flow path component 10 can be a structure divided along a horizontal plane that includes the axis of the rotating shaft portion 44 of the valve mechanism 40. Alternatively, the inner component 50 can also be a structure divided along a plane perpendicular to the axis of the rotating shaft portion 44 of the valve mechanism 40.

[0090] This application claims priority to Japan Patent Application No. 2023-117570, filed with the Japan Patent Office on July 19, 2023, the entire contents of which are incorporated herein by reference.

Claims

1. An exhaust heat recovery device that recovers heat of exhaust gas discharged from an engine by heat exchange with a fluid, wherein, The exhaust heat recovery device is provided with: a first flow path member in which a first flow path through which exhaust gas flows is formed; a second flow path member which is disposed adjacent to the first flow path member, in which a second flow path which bypasses a portion of the first flow path is formed, and which has a heat exchange portion which performs heat exchange between exhaust gas flowing in the second flow path and the fluid; and a valve mechanism which is provided in the first flow path, the first flow path member has: an outflow port through which exhaust gas flows out from the first flow path to the second flow path; an inflow port through which exhaust gas flows in from the second flow path to the first flow path; and a first standing portion which is located at a position in the first flow path which is more upstream than the inflow port and which stands to the inside of the first flow path in a direction orthogonal to the flow direction of the exhaust gas, the valve mechanism has: a rotating shaft portion; a valve body which rotates in conjunction with the rotating shaft portion and which is used to close or open the first flow path; and a gate portion which rotates in conjunction with the rotating shaft portion and which is used to close or obstruct the flow of exhaust gas from the inflow port, in a heat recovery state, the valve body of the valve mechanism closes the first flow path, and the gate portion opens the flow of exhaust gas from the inflow port, in a heat non-recovery state, the valve body of the valve mechanism opens the first flow path, and the gate portion closes or obstructs the flow of exhaust gas from the inflow port, in the heat non-recovery state, a gap is formed in a separation direction of the inflow port and the gate portion, the first standing portion is formed so that its height in a height direction from the outside to the inside of the first flow path is greater than the gap, the front end of the gate portion abuts against or approaches the first standing portion in the heat non-recovery state.

2. The exhaust heat recovery device according to claim 1, wherein the gate portion has a protruding portion which protrudes to the outside in a radius direction of rotation of the valve mechanism, in the heat non-recovery state, the protruding portion abuts against or approaches an inner wall of the first flow path member on the downstream side of the inflow port in the flow direction of the exhaust gas, in the heat non-recovery state, rotation of the valve mechanism is limited by at least one of the operation in which the front end of the gate portion abuts against the first standing portion, or the operation in which the protruding portion abuts against the inner wall of the first flow path member.

3. The exhaust heat recovery device according to claim 1, wherein a face on the downstream side of the flow direction of the exhaust gas of the first standing portion abuts against or opposes the front end of the gate portion, and a face on the upstream side of the flow direction of the exhaust gas of the first standing portion abuts against or opposes the valve body.

4. The exhaust heat recovery device according to claim 1, wherein the first flow path member has a second standing portion which stands to the inside of the first flow path in a direction orthogonal to the flow direction of the exhaust gas, the second standing portion is located at a position in the inner side surface of the first flow path which is on the side opposite to the first standing portion and which is more upstream than the first standing portion in the flow direction of the exhaust gas, ​ In the heat recovery state, a surface of the first erected portion on an upstream side of a flow direction of the exhaust gas abuts against or opposes the valve body, In the heat recovery state, a surface of the second erected portion on a downstream side of the flow direction of the exhaust gas abuts against or opposes the valve body, In the heat recovery state, the valve body abuts against at least one of the first erected portion and the second erected portion.

5. The exhaust heat recovery device according to claim 4, wherein the exhaust heat recovery device further includes an inner member that covers at least a portion of the inner surface, the first erected portion and the second erected portion are formed at an end portion of a downstream side of the inner member in the flow direction of the exhaust gas.

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