Exhaust heat recovery device

Abstract

To suppress inflow of exhaust gas into a heat exchange part when heat recovery from exhaust gas is unnecessary and prevent deterioration of exhaust efficiency.SOLUTION: An exhaust heat recovery device 1 includes: a first flow passage member 10 having a first flow passage in which exhaust gas flows; a second flow passage member 20 located adjacent to the first flow passage member 10, having a heat exchange part 30 and including a second flow passage; and a valve mechanism 40 for opening / closing the first flow passage and shutting off or inhibiting a flow of exhaust gas from the second flow passage. The valve mechanism 40 includes: a valve element 43 for closing the first flow passage in a heat recovery state where the first flow passage is closed; and a shutter part 42 for shutting off or inhibiting a flow of exhaust gas from the second flow passage in a heat non-recovery state where the first flow passage is opened. The first flow passage member 10 has a first erect part 17 erecting toward inside of the first flow passage. An end part 43a of the valve element 43a abuts on or is located adjacent to the first erect part 17 in the heat recovery state of the valve element 43.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an exhaust heat recovery device. [Background technology]

[0002] Patent Document 1 discloses an exhaust heat recovery device having a first flow path member having a first flow path through which exhaust gas flows, a second flow path member provided adjacent to the first flow path and having a second flow path that bypasses the first flow path, and a heat exchange section that exchanges heat between the exhaust gas and a refrigerant.

[0003] The exhaust heat recovery device described in Patent Document 1 has a butterfly valve that opens and closes the first flow path by a rotating axis perpendicular to the flow direction of the exhaust gas in the first flow path, and a shutter portion that blocks the outlet from the second flow path, which is a bypass, when the butterfly valve opens the first flow path, and opens the outlet when the butterfly valve blocks the first flow path, and is equipped with a valve mechanism that switches the flow path of the exhaust gas to the first flow path or the second flow path. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-188567 Summary of the Invention [Problem to be solved by the invention]

[0005] In the exhaust heat recovery device disclosed in Patent Document 1, it is assumed that the outer peripheral wall of the cylindrical shutter part will come into surface contact with the inner wall of the first flow path member to block the outlet, but to achieve this, it is necessary to accurately match the dimensional relationship between the two. In other words, if the cylindrical shape of the shutter part is formed relatively larger than the inner wall (inner circumference) of the first flow path member due to the tolerance between the two, the tip of the shutter part will come into corner contact with the inner wall of the first flow path member. [Means for solving the problem]

[0006] According to one aspect of the present invention, there is provided an exhaust heat recovery device that recovers heat of exhaust gas discharged from an engine by heat exchange with a fluid, the device comprising: a first flow path member having a first flow path formed therein through which exhaust gas flows; a second flow path member provided adjacent to the first flow path member, having a second flow path formed therein that bypasses a part of the first flow path and having a heat exchange portion that exchanges heat between the exhaust gas flowing in the second flow path and the fluid; and a valve mechanism provided in the first flow path, the first flow path member having an exhaust gas outlet from the first flow path to the second flow path, an exhaust gas inlet from the second flow path to the first flow path, and a first upright portion that is located upstream of the inlet in the first flow path, extends in a direction perpendicular to the exhaust gas flow direction and upright toward the inside of the first flow path, the valve mechanism comprising: a rotating shaft portion; An exhaust heat recovery device is provided, comprising: a valve body that rotates with rotation and blocks or opens the first flow path; and a shutter portion that rotates with rotation of the rotating shaft portion and blocks or obstructs the flow of exhaust gas from the inlet, wherein in a heat recovery state, the valve body of the valve mechanism blocks the first flow path and the shutter portion opens the flow of exhaust gas from the inlet, and in a heat non-recovery state, the valve body of the valve mechanism opens the first flow path and the shutter portion blocks or obstructs the flow of exhaust gas from the inlet, and in the heat non-recovery state, a gap is formed in the direction separating the inlet and the shutter portion, and in the height direction from the outside to the inside of the first flow path, the first upright portion is formed larger than the gap, and a tip of the shutter portion abuts or is close to the first upright portion in the heat non-recovery state. Effect of the Invention

[0007] According to the exhaust heat recovery device of the present invention, in the heat recovery state, it is possible to sufficiently achieve blocking of the inlet or obstruction of the gas flow while preventing corner contact between the tip of the shutter portion and the inner wall of the first flow path member. [Brief description of the drawings]

[0008] [Figure 1]FIG. 1 is a perspective view illustrating an exhaust heat recovery device according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a partially cutaway front view of the exhaust heat recovery device according to the first embodiment. [Diagram 3] FIG. 3 is a side view seen from the upstream side of the first flow passage, illustrating the heat recovery state of the exhaust heat recovery device according to the first embodiment. [Figure 4] FIG. 4 is a perspective view illustrating a valve mechanism of the exhaust heat recovery device according to the first embodiment. [Diagram 5] FIG. 5 is a partially cutaway front view of the exhaust heat recovery device according to the first embodiment. [Figure 6] FIG. 6 is a side view seen from the upstream side of the first flow passage, illustrating the exhaust heat recovery device according to the first embodiment in a heat non-recovery state. [Figure 7] FIG. 7 is a partially cutaway front view of the exhaust heat recovery device according to the second embodiment. [Figure 8] FIG. 8 is a partially cutaway front view of the exhaust heat recovery device 2 according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] [First embodiment] Hereinafter, an exhaust heat recovery device 1 according to a first embodiment of the present invention will be described with reference to the drawings.

[0010] Fig. 1 is a perspective view illustrating an exhaust heat recovery device 1 according to a first embodiment of the present invention. Fig. 2 is a front view showing a part of the exhaust heat recovery device 1 in a cutaway state. Fig. 3 is a side view showing the heat recovery state of the exhaust heat recovery device 1 shown in Fig. 2, viewed from the upstream side of a first flow path 14.

[0011] As shown in FIG. 1, the exhaust heat recovery device 1 includes a first passage member 10, a second passage member 20, and a heat exchange section 30. The first passage member 10 and the second passage member 20 are arranged in a direction parallel to the heat exchanger 30.

[0012] The first flow path member 10 has a main body 11, a first inlet portion 12, and a first outlet portion 13. The main body 11 has a hollow structure, and a first flow path 14 through which the exhaust gas flows is formed inside the main body 11.

[0013] The first inlet section 12 is an opening on one side of the main body section 11 and is connected to a flow path of exhaust gas from the engine. The first outlet section 13 is an opening on the other side of the main body section 11 and is connected to a flow path of exhaust gas. The first inlet section 12 is located upstream of the first outlet section 13 in the exhaust gas flow.

[0014] The main body 11 is formed with a first upstream opening 15 serving as an outlet through which exhaust gas flows from the first flow path 14 to the second flow path 24 (see FIG. 2), and a first downstream opening 16 serving as an inlet through which exhaust gas flows from the second flow path 24 into the first flow path 14.

[0015] The second flow path member 20 is provided adjacent to the first flow path member 10. The second flow path member 20 has a main body portion 21, a second upstream opening 22, and a second downstream opening .

[0016] The main body 21 has a hollow structure, and a second flow passage 24 is formed inside the main body 21, through which the exhaust gas that has bypassed a part of the first flow passage 14 flows.

[0017] The second upstream opening 22 is located upstream of the second flow path 24, and takes in the exhaust gas that has detourged from a part of the first flow path 14 into the inside of the main body 21. The second downstream opening 23 causes the exhaust gas that has flowed inside the main body 21 to flow into the first flow path 14.

[0018] The second upstream opening 22 is connected to a first upstream opening 15 formed in the first flow path member 10 by a first communicating portion 25. In addition, the second downstream opening 23 is connected to a first downstream opening 16 formed in the first flow path member 10 by a second communicating portion 26.

[0019] The inside of the first communication portion 25, the interior of the second flow path member 20, and the inside of the second communication portion 26 form a second flow path 24.

[0020] The above-described first flow path member 10 and second flow path member 20 allow exhaust gas to be diverted from the first flow path 14 to the second flow path member 20 through the first communication portion 25. In addition, the exhaust gas that has flowed through the second flow path member 20 can be made to flow into the first flow path 14 through the second communication portion 26.

[0021] The second flow path member 20 has a heat exchange section 30. The heat exchange section 30 has a refrigerant inlet section 31, a heat exchange section main body section 32, and a refrigerant outlet section 33, and coolant flows through the heat exchange section 30 as a refrigerant. The heat exchange section 30 exchanges heat between the exhaust gas flowing through the second flow path 24 and the refrigerant.

[0022] The refrigerant inlet section 31 is a hollow tube-shaped section that connects a flow path (not shown) through which cooling water flows before cooling the engine, and the inside of the heat exchanger main body 32. The refrigerant inlet section 31 allows the cooling water, which serves as a refrigerant and is supplied from the flow path, to flow into the inside of the heat exchanger main body 32.

[0023] The refrigerant outlet 33 is a hollow tube-shaped section that connects the inside of the heat exchanger main body 32 to a flow path (not shown) that supplies cooling water to the engine. The refrigerant inlet 31 causes the cooling water that has flowed inside the heat exchanger main body 32 to flow out into the flow path.

[0024] When exhaust gas flows through a portion of the main body 21 of the second flow path member 20 that is surrounded by the heat exchanger main body 32 (a portion of the second flow path 24 that is surrounded by the heat exchanger main body 32), the heat exchanger 30 exchanges heat between the exhaust gas and the cooling water flowing inside the heat exchanger main body 32, and transfers and recovers the heat of the exhaust gas to the cooling water. Note that a state in which the valve mechanism 40 described below closes the first flow path 14 and the exhaust gas flows through the second flow path 24 to perform the heat exchange is referred to as a heat recovery state. On the other hand, a 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 referred to as a non-heat recovery state.

[0025] In the first embodiment, the first flow path member 10 has a first upright portion 17 that stands 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. It can also be said that the first upright portion 17 is disposed between the first upstream opening 15 and the first downstream opening 16 on the inner surface of the first flow path member 10. Moreover, the first upright portion 17 is formed across the first downstream opening 16 in a direction perpendicular to the flow direction of the exhaust gas.

[0026] The first flow path member 10 has a second upright portion 18 that stands up toward the inside of the first flow path 14 on the inner surface of the first flow path member 10. The second upright portion 18 is disposed on the inner surface of the first flow path member 10, on the side opposite to the surface on which the first upright portion 17 is formed. In the heat recovery state, the second upright portion 18 is located upstream of the valve body 43 (FIG. 4) of the valve mechanism 40. In addition, the second upright portion 18 is formed in a direction perpendicular to the flow direction of the exhaust gas.

[0027] In this embodiment, the first upright portion 17 is formed such that in the heat non-recovery state (FIG. 5), the height h1 from the inner surface of the first flow path member 10 is larger than the gap d1 formed in the separation direction between the first downstream opening 16 and the valve mechanism 40 (shutter portion 42). Also, in the heat recovery state of the valve mechanism 40 (FIG. 2), the second upright portion 18 is formed such that the height h2 from the inner surface of the first flow path member 10 is larger than the gap d2 in the separation direction between the inner surface of the first flow path member 10 and the valve mechanism 40 (valve body 43).

[0028] As shown in FIG. 2, the exhaust heat recovery device 1 includes a valve mechanism 40 inside the first passage member 10.

[0029] FIG. 4 is a perspective view illustrating the valve mechanism 40 of the exhaust heat recovery device 1 shown in FIG.

[0030] The valve mechanism 40 has a butterfly valve 41 for opening and closing the first flow path 14, a shutter portion 42 for blocking or obstructing 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.

[0031] A rotary shaft portion 44 is connected to the valve body 43 and is rotatably supported within the first flow path 14. The rotary shaft portion 44 is connected to a drive shaft of an actuator (not shown) as a drive portion.

[0032] The valve element 43 in the butterfly valve 41 is a plate-like member formed with a length and width sufficient to close the first flow path 14. The valve element 43 can switch between opening and closing the first flow path 14 by rotation of a rotating shaft portion 44.

[0033] The shutter portion 42 is provided on the valve body 43. The shutter portion 42 has a plate-shaped shutter main body portion 42a and a pair of connecting portions 42b. The shutter main body portion 42a closes the first downstream opening 16 in the heat non-recovery state, and opens the first downstream opening 16 in the heat non-recovery state.

[0034] The connecting portion 42b supports the shutter main body portion 42a at a distance from the valve body 43 such that the shutter main body portion 42a does not come into contact with the inner wall portion (first downstream opening 16) of the first flow path member 10 and the first downstream opening 16 can be blocked.

[0035] The shutter portion 42 has a protrusion 45 that protrudes outward in the direction of the rotation radius of the rotating valve mechanism 40. The surface of the protrusion 45 is formed in a curved shape, and in the non-heat recovery state (FIGS. 5 and 6), the protrusion 45 abuts against or is close to the inner surface of the first flow path member 10 on the downstream side of the first downstream opening 16 in the flow direction of the exhaust gas.

[0036] In the non-heat recovery state, the tip 42e (end face) of the shutter portion 42 on the upstream side in the flow direction of the exhaust gas is configured to abut on or be close to the first upright portion 17.

[0037] <Valve mechanism operation and exhaust gas flow> Next, the operation of the valve mechanism 40 and the flow of exhaust gas in the exhaust heat recovery system 1 according to the first embodiment will be described.

[0038] Fig. 5 is a partially cutaway front view of the exhaust heat recovery device 1. Fig. 6 is a side view of the exhaust heat recovery device 1 shown in Fig. 5 in a non-heat recovery state, as viewed from the upstream side of the first flow passage 14.

[0039] The valve mechanism 40 in the exhaust heat recovery device 1 can be switched between a heat recovery state (Figures 2 and 3) in which the first downstream opening 16 is opened by the shutter portion 42 and the first flow path 14 is blocked by the butterfly valve 41, and a non-heat recovery state (Figures 5 and 6) in which the first downstream opening 16 is blocked by the shutter portion 42 and the first flow path 14 is opened by the butterfly valve 41.

[0040] In the first embodiment, as shown in Fig. 5 and Fig. 6, when the valve mechanism 40 rotates so that the main surface of the valve body 43 of the valve mechanism 40 is parallel to the flow direction of the exhaust gas (see the arrow in Fig. 5) and the heat non-recovery state is entered, the tip 42e of the shutter portion 42 abuts against the surface of the first upright portion 17 on the downstream side in the exhaust gas flow direction, and the convex portion 45 formed on the shutter 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 exhaust gas flow direction. Note that in the heat non-recovery state, the tip 42e may abut against the first upright portion 17, and the convex portion 45 may be close to the inner surface of the first flow path member 10. Also, in the heat non-recovery state, the tip 42e may be close to the first upright portion 17, and the convex portion 45 may abut against the inner surface of the first flow path member 10. In the non-heat recovery state, the tip 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. "Close" here refers to a state in which they face each other with a small gap therebetween.

[0041] In this state, the exhaust gas flows into the first flow path member 10 from the first inlet portion 12 , flows through the first flow path 14 formed inside the first flow path member 10 , and flows out from the first outlet portion 13 .

[0042] On the other hand, in the heat non-recovery state, the end 43a of the valve element 43 located on the upstream side in the flow direction approaches the first upright portion 17, and the end 43b of the valve element 43 located on the downstream side in the flow direction rotates in a direction approaching the second upright portion 18, causing the valve mechanism 40 to rotate so that the main surface of the valve element 43 of the valve mechanism 40 is perpendicular to the flow direction of the exhaust gas, and the valve mechanism 40 transitions to the heat recovery state. The second upright portion 18 will be described later.

[0043] 2 and 3, in the heat recovery state, the upstream surface of the first upright portion 17 in the flow direction comes into contact with the downstream surface of the end 43a of the valve body 43 in the flow direction. Also, the downstream surface of the second upright portion 18 in the flow direction comes into contact with the upstream surface of the end 43b of the valve body 43 in the flow direction.

[0044] In this state, when exhaust gas flows into the first flow path member 10 from the first inlet portion 12, it stagnates in the space S formed by the valve body 43 and the first flow path member 10, and flows into the second flow path 24 from the first upstream opening 15 (see the arrow in Figure 2).

[0045] In the heat recovery state, either the upstream surface of the first standing portion 17 and the downstream surface of the end 43a of the valve body 43, or the downstream surface of the second standing portion 18 and the upstream surface of the end 43b of the valve body 43 may be configured to abut.

[0046] The exhaust gas flows through the second flow path 24 inside the second flow path member 20, and exchanges heat with the refrigerant flowing through the heat exchange section 30. After flowing through the second flow path 24, the exhaust gas returns to the first flow path 14 from the first downstream opening 16, flows through the first flow path, and flows out from the first outlet section 13.

[0047] <Action and effect> The exhaust heat recovery device 1 of the first embodiment comprises a first flow path member 10 having a first flow path 14 formed therein through which exhaust gas flows, a second flow path member 20 provided adjacent to the first flow path member 10 and having a second flow path 24 formed therein that bypasses part of the first flow path 14 and having a heat exchange section 30 that exchanges heat between the exhaust gas flowing through the second flow path 24 and the refrigerant, and a valve mechanism 40 disposed within the first flow path member 10 and having a butterfly valve 41 that opens and closes the first flow path 14, and a shutter section 42 that blocks or obstructs the flow of exhaust gas from the second flow path 24.

[0048] The first flow path member 10 is formed with a first upstream opening 15 as an outlet for exhaust gas from the first flow path 14 to the second flow path 24, and a first downstream opening 16 as an inlet for exhaust gas from the second flow path 24 to the first flow path 14.

[0049] The valve mechanism 40 is configured to be switched between a heat recovery state and a heat non-recovery state by rotation of a rotary shaft portion 44 that is perpendicular to the flow direction of the exhaust gas in the first flow passage 14. As described above, in the heat non-recovery state, the shutter portion 42 closes the first downstream opening 16, and the butterfly valve 41 opens the first flow passage 14. In the heat recovery state, the shutter portion 42 opens the first downstream opening 16, and the butterfly valve 41 closes the first flow passage 14.

[0050] The first flow path member 10 has a first upright portion 17 that stands toward 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 opening 16 in the first flow path 14. In addition, 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 that is generated in the separation direction between the first downstream opening 16 and the shutter portion 42 that closes the first downstream opening 16 in the heat non-recovery state.

[0051] Therefore, in the non-heat recovery state, the first standing portion 17 can block the gap d1 formed in the direction of separation between the first downstream opening 16 and the shutter portion 42. Here, when exhaust gas flows through the first flow passage 14, the flow makes it easier for the first downstream opening 16 to draw in exhaust gas from the second flow passage 24. However, in the exhaust heat recovery device 1, despite the presence of a gap between the shutter portion 42 and the first downstream opening 16, the formation of the first standing portion 17 suppresses the drawing in of such exhaust gas. This makes it possible to prevent the exhaust gas from flowing into the second flow passage 24 at the first upstream opening 15.

[0052] Therefore, it is possible to suppress the inflow of exhaust gas into the heat exchange section 30 when heat recovery from the exhaust gas is not required, and to prevent a decrease in exhaust efficiency.

[0053] In a conventional exhaust heat recovery device, the first flow path is opened and the second flow path is closed by bringing the main surface of the cylindrically formed shutter into surface contact with the inner wall of the first flow path member. However, in this structure, if there is an error in the dimensions of the shutter and the inner wall (inner circumference) of the first flow path member, a corner collision may occur in which a part of the shutter interferes with the inner wall of the first flow path member.

[0054] On the other hand, the exhaust heat recovery device 1 includes the first upright portion 17 and forms the above-mentioned gap d1, so that even if the size and positioning of the valve mechanism 40 and the first flow path member 10 are not strictly designed, there is no risk of the valve mechanism 40 coming into contact with the inner surface of the first flow path member 10 due to the rotational movement of the valve mechanism 40. The exhaust heat recovery device 1 can prevent corner contact, in which a part of the shutter portion interferes with the inner wall of the first flow path member. Moreover, the exhaust heat recovery device 1 can sufficiently block or obstruct the gas flow from the second flow path 24 at the first downstream opening 16 when the valve mechanism 40 is in a non-heat recovery state.

[0055] The first flow path member 10 has, on an inner surface opposite to the first upright portion 17, a second upright portion 18 that stands toward the inside of the first flow path 14 in a direction perpendicular to the flow direction of the exhaust gas.

[0056] The second raised portion 18 is larger than the gap d2 in the direction of separation between the inner surface of the first flow path member 10 and the butterfly valve 41 when the valve mechanism 40 is in the heat recovery state, and is formed downstream of the butterfly valve 41 when the valve mechanism 40 is in the heat recovery state.

[0057] When the valve mechanism 40 is in a heat recovery state, the second upright portion 18 can block the gap d2 in the separation direction between the inner surface of the first flow path member 10 and the butterfly valve 41 from the downstream side.

[0058] This makes it possible to prevent exhaust gas from flowing into the first flow passage 14 in a heat recovery state in which the first downstream opening 16 is opened by the shutter portion 42 and the first flow passage 14 is closed by the butterfly valve 41.

[0059] Therefore, the exhaust heat recovery device 1 can suppress leakage of exhaust gas into the first passage 14 when heat recovery from exhaust gas is required, and can prevent a decrease in heat recovery efficiency.

[0060] In the heat recovery state of the exhaust heat recovery device 1 according to the first embodiment, the surface on the downstream side in the flow direction at the end of the valve body 43 of the valve mechanism 40 abuts against the surface on the upstream side in the flow direction of the first upright portion 17. Also, the surface on the upstream side in the flow direction at the end of the valve body 43 abuts against the surface on the downstream side in the flow direction of the second upright portion 18.

[0061] As a result, the first upright portion 17 and the second upright portion 18 contribute to the positioning of the butterfly valve 41 when the valve mechanism 40 is in the heat recovery state.

[0062] Therefore, leakage of exhaust gas into the first passage 14 in a case where heat recovery from the exhaust gas is required is suppressed, and the effect of preventing a decrease in heat recovery efficiency is promoted.

[0063] Furthermore, if the valve mechanism 40 is configured to abut either the first upright portion 17 or the second upright portion 18, the positioning effect of the butterfly valve 41 in the heat recovery state of the valve mechanism 40 can be obtained.

[0064] The shutter portion 42 has a protrusion 45 that protrudes outward in the direction of the rotation radius of the rotating valve mechanism 40. When the valve mechanism 40 is in a heat non-recovery state, the protrusion 45 abuts against the inner surface of the first flow path member 10 downstream of the first downstream opening 16 in the flow direction of the exhaust gas.

[0065] The end of the valve mechanism 40 on the upstream side in the exhaust gas flow direction is likely to come into contact with the inner surface of the first flow path member 10 because the valve mechanism 40 is in advance when rotating. In contrast, according to the exhaust heat recovery device 1, the shutter portion 42 has a convex portion 45. Therefore, even if the gap between the end of the valve mechanism 40 on the upstream side in the exhaust gas flow direction and the inner surface of the first flow path member 10 is designed with a margin that does not contact, the end of the valve mechanism 40 on the downstream side in the exhaust gas flow direction abuts against the convex portion 45. As a result, the shutter portion 42 is positioned in the non-heat recovery state of the valve mechanism 40. Note that the convex portion 45 comes into contact with the inner surface of the first flow path member 10 from an obtuse angle direction, and the surface of the convex portion 45 is formed in a curved shape, so that galling (biting into the inner surface) is unlikely to occur.

[0066] [Second embodiment] Next, an exhaust heat recovery device 2 according to a second embodiment of the present invention will be described with reference to the drawings. In the second embodiment, components having the same functions as those in the first embodiment are given the same reference numbers and detailed descriptions thereof will be omitted.

[0067] 7 and 8 are partially cutaway front views of the exhaust heat recovery device 2 according to the second embodiment. Fig. 7 illustrates the valve mechanism 40 in the exhaust heat recovery device 2 in a heat recovery state, and Fig. 8 illustrates the valve mechanism 40 in a non-heat recovery state.

[0068] 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 member 70 in the flow direction of the exhaust gas.

[0069] That is, the exhaust heat recovery device 2 includes an inner member 50 that is disposed inside the first flow path member 10 and covers at least a part of the inner surface of the first flow path member 10. The inner member 50 is integrally formed with a first upright portion 51 that is folded back toward the inside of the first flow path 14 and a second upright portion 52.

[0070] In the second embodiment, the first upright portion 51 is formed so that a height H1 from the inner surface of the first flow path member 10 is larger than a gap D1 formed in the separation direction between the first downstream opening 16 and the valve mechanism 40 (shutter portion 42) when the valve mechanism 40 is in a heat non-recovery state (FIG. 8). Moreover, the second upright portion 52 is formed so that a height H2 from the inner surface of the first flow path member 10 is larger than a gap D2 in the separation direction between the inner surface of the first flow path member 10 and the valve mechanism 40 (valve body 43) when the valve mechanism 40 is in a heat recovery state (FIG. 7).

[0071] In the exhaust heat recovery device 2, when the valve mechanism 40 is in the heat recovery state, the upstream surface of the first upright portion 51 in the flow direction comes into contact with the downstream surface of the end 43a of the valve body 43 in the flow direction. Also, the downstream surface of the second upright portion 52 in the flow direction comes into contact with the upstream surface of the end 43b of the valve body 43 in the flow direction.

[0072] As a result, the first upright portion 51 and the second upright portion 52 contribute to the positioning of the butterfly valve 41 when the valve mechanism 40 is in the heat recovery state.

[0073] Therefore, the exhaust heat recovery device 2 suppresses leakage of exhaust gas into the first passage 14 when heat recovery from the exhaust gas is required, and the effect of preventing a decrease in heat recovery efficiency is promoted.

[0074] Moreover, in the exhaust heat recovery device 2 according to the second embodiment, the exhaust gas comes into contact with the inner member 50 provided inside the first passage member 10. This makes it possible to reduce the thermal stress difference caused in the first passage member 10 by the heat of the exhaust gas. This makes it possible to increase the heat resistance strength of the exhaust heat recovery device 2.

[0075] [Other embodiments] Although the embodiments of the present invention have been described above, the above-mentioned embodiments merely illustrate some of the application examples of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above-mentioned embodiments.

[0076] In the first embodiment, the fluid that cools the exhaust gas may be a fluid other than cooling water, and a medium such as a liquid or gas that is suitable for heat exchange can be applied.

[0077] In this embodiment, the valve mechanism 40 has a structure in which a pair of connecting parts 42b support both ends of the shutter main body part 42a. In contrast, for example, the connecting part 42b may be one in the center of the shutter main body part 42a. Also, a plurality of connecting parts 42b may be arranged in parallel to form a so-called louver.

[0078] In the exhaust heat recovery device 2 according to the second embodiment, the inner member 50 provided inside the first flow path member 10 may be structured to be divided along a horizontal plane including the axis of the rotating shaft portion 44 of the valve mechanism 40. Moreover, the inner member 50 may be structured to be divided along a plane perpendicular to the axis of the rotating shaft portion 44 of the valve mechanism 40. [Explanation of symbols]

[0079] 1 Exhaust heat recovery device 10 First flow path member 11 Main body 12 1st inflow section 13 First Outlet 14 First flow path 15 First upstream opening 16 1st downstream opening 17 1st standing section 18 Second standing section 20 Second flow path member 21 Main body 22 Second upstream opening 23 2nd downstream opening 24 Second Flow Stream 25 1st communication part 26 2nd connection part 30 Heat exchange section 31 Refrigerant inlet 32 Heat exchanger body 33 Refrigerant outlet 40 Valve mechanism 41 Butterfly valve 42 Shutter section 42e End of shutter part 43 Valve body 43a, 43b End of valve body 44 Rotating shaft 45 Convex 50 Inner member 51 1st standing section 52 Second standing section S space

Claims

1. An exhaust heat recovery device that recovers heat from exhaust gas discharged from an engine by heat exchange with a fluid, a first flow path member having a first flow path formed therein through which exhaust gas flows; a second flow path member provided adjacent to the first flow path member, having a second flow path formed therein that bypasses a part of the first flow path, and having a heat exchange portion that exchanges heat between the exhaust gas flowing in the second flow path and the fluid; A valve mechanism provided in the first flow path; Equipped with The first flow path member is an outlet for exhaust gas from the first flow path to the second flow path; an inlet for exhaust gas from the second flow path to the first flow path; a first upright portion that is located upstream of the inlet in the first flow path, extends in a direction perpendicular to the flow direction of the exhaust gas, and uprights toward an inside of the first flow path, The valve mechanism includes: A rotating shaft portion, a valve body that rotates in association with rotation of the rotary shaft portion and closes or opens the first flow path; a shutter portion that rotates in association with the rotation of the rotating shaft portion and blocks or obstructs the flow of exhaust gas from the inlet, In a heat recovery state, the valve body of the valve mechanism closes the first flow path, and the shutter portion opens the flow of exhaust gas from the inlet, In a heat non-recovery state, the valve body of the valve mechanism opens the first flow path, and the shutter portion blocks or obstructs the flow of exhaust gas from the inlet, In the heat non-recovery state, a gap is formed in a direction away from the inlet and the shutter portion, In a height direction from the outside to the inside of the first flow path, the first upright portion is formed larger than the gap, A tip of the shutter portion abuts or is adjacent to the first upright portion in the heat non-recovery state. Exhaust heat recovery device.

2. 2. The exhaust heat recovery system according to claim 1, the shutter portion has a convex portion that protrudes outward in a rotation radius direction of the rotating valve mechanism, the protrusion abuts against or is adjacent to an inner wall of the first flow path member downstream of the inlet in a flow direction of the exhaust gas in the heat non-recovery state, In the heat non-recovery state, rotation of the valve mechanism is restricted by at least one of the tip of the shutter portion abutting against the first upright portion or the convex portion abutting against an inner wall of the first flow path member. Exhaust heat recovery device.

3. 2. The exhaust heat recovery system according to claim 1, In the first upright portion, a downstream surface in the flow direction of the exhaust gas abuts against or faces the tip of the shutter portion, and an upstream surface in the flow direction of the exhaust gas abuts against or faces the valve body. Exhaust heat recovery device.

4. 2. The exhaust heat recovery system according to claim 1, the first flow path member has a second upright portion extending in a direction perpendicular to the flow direction of the exhaust gas and upright toward an inside of the first flow path, the second upright portion is located on an inner surface of the first flow passage on a side facing the first upright portion and upstream of the first upright portion in a flow of exhaust gas; In the heat recovery state, the first upright portion abuts or faces the valve body at an upstream surface in the flow direction of the exhaust gas. In the heat recovery state, the second upright portion abuts against or faces the valve body at a downstream surface in a flow direction of the exhaust gas, The valve body abuts against at least one of the first upright portion and the second upright portion in the heat recovery state. Exhaust heat recovery device.

5. 5. The exhaust heat recovery system according to claim 4, an inner member covering at least a portion of the inner surface; The first upright portion and the second upright portion are formed at a downstream end of the inner member in a flow direction of exhaust gas. Exhaust heat recovery device.

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