JP2015165129A - Exhaust heat recovery device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exhaust heat recovery device which prevents medium from boiling within a heat exchanger.SOLUTION: An exhaust heat recovery device includes a heat exchanger 3 carrying out heat exchange between an exhaust gas and a medium, a first flow passage 4 by which the exhaust gas passes through the heat exchanger 3, a second flow passage 5 by which the exhaust gas bypasses the heat exchanger 3, a first valve body 30 which opens and closes the second flow passage 5, and a second valve body 31 which opens and closes the first flow passage 4. The exhaust gas and the medium flow in the same direction within the heat exchanger 3. In a lower part of the heat exchanger 3 with the heat exchanger 3 installed in a vehicle, a recovery space 13 for recovering condensate water is provided.

Description

  The present invention relates to an exhaust heat recovery apparatus.

  Conventionally, as an exhaust heat recovery device for recovering exhaust heat of an internal combustion engine, a flat case is provided between a cylindrical case attached to an exhaust pipe, a bypass passage disposed in an inner center portion of the case, and the case and the bypass passage. A flat tube formed in a donut shape from a plurality of upstream sides to a downstream side, provided with an exhaust gas passage through which exhaust gas circulates between them, and a tube laminate, and the downstream side of the bypass passage is opened and closed What has a valve body is known (refer to patent documents 1).

  In this exhaust heat recovery device, when the valve body is closed, the exhaust gas flows through the exhaust gas passage from above to below, and the medium (cooling water) flows through the flat tube from below to above to heat each other. Exchange. Further, when the valve body is opened, the exhaust gas can flow through the bypass passage and the exhaust gas passage.

Japanese Patent No. 5108462

  However, in the exhaust heat recovery device of the prior art, the exhaust gas in a high temperature state before heat exchange and the cooling water whose temperature has been increased by heat exchange are heat-exchanged at the upper part of the tube stack, There is a risk of boiling water.

  Further, since the valve body only opens and closes the bypass passage, when the valve body is opened, the exhaust gas flows through the bypass passage and the exhaust gas passage, and the cooling water does not need to exchange heat at a high temperature. However, the cooling water may be heated and the cooling water may boil.

  Therefore, an object of the present invention is to provide an exhaust heat recovery apparatus that solves the above-described problems.

In an exhaust system such as an internal combustion engine, a heat exchanger that performs heat exchange between exhaust gas and a medium, a first flow path through which the exhaust gas passes through the heat exchanger, and the exhaust gas bypasses the heat exchanger. A second flow path, a first valve body for opening and closing the second flow path, and a second valve body for opening and closing the first flow path,
The exhaust gas and the medium circulate in the same direction in the heat exchanger,
A recovery space for recovering condensed water is provided in a lower part of the heat exchanger in a vehicle-mounted state.

  The invention according to claim 2 is the invention according to claim 1, wherein the heat exchanger has a plurality of fluid passages through which the exhaust gas flows, and the fluid passages are arranged in parallel from the upstream side toward the downstream side. It is characterized by having set up.

  The invention according to claim 3 is characterized in that, in the invention according to claim 1 or 2, the exhaust gas circulates from below to above in the heat exchanger in a vehicle-mounted state. is there.

  According to a fourth aspect of the present invention, in the first, second, or third aspect of the invention, the second flow path is provided in a central portion of the case, a communication hole is provided in a lower portion of the second flow path, and the second The recovery space is provided below the flow path, the second flow path and the first flow path communicate with each other through the recovery space, and the first valve body is provided on the downstream side of the communication hole. To do.

  The invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein the recovery space communicates with the downstream side of the heat exchanger in the first flow path or the second flow path. It is characterized by that.

  The invention described in claim 6 is characterized in that, in the invention described in any one of claims 1 to 5, fins are provided in the fluid flow path.

  According to the present invention, the exhaust gas and the medium flow in the same direction in the heat exchanger, so that the high temperature medium after heat exchange exchanges heat with the low temperature exhaust gas after heat exchange. Therefore, boiling of the medium can be suppressed.

  Further, by providing a first valve body that opens and closes the second flow path and a second valve body that opens and closes the first flow path, the exhaust gas can exchange heat when heat exchange is unnecessary. Inflow to the container side can be suppressed, the medium that has reached a high temperature can be further prevented from receiving heat, and boiling of the medium can be suppressed.

1 is a front view of an exhaust heat recovery apparatus according to Embodiment 1 of the present invention. The top view of FIG. The left view of FIG. FIG. 3 is a cross-sectional view taken along line AA in FIG. 2. Sectional drawing of the state which opened the 1st valve body from the state of FIG. BB sectional drawing of FIG. The CC sectional view taken on the line of FIG. The DD sectional view taken on the line of FIG. The EE sectional view taken on the line of FIG. FF sectional view taken on the line of FIG. The GG sectional view taken on the line of FIG. The longitudinal cross-sectional view of the exhaust heat recovery apparatus of Example 2 of this invention. HH sectional view taken on the line of FIG. JJ sectional view taken on the line of FIG. The left view of the exhaust heat recovery apparatus of Example 3 of this invention. KK sectional drawing of FIG. The longitudinal cross-sectional view of an example of the exhaust heat recovery apparatus of Example 4 of this invention. LL sectional view taken on the line of FIG. FIG. 19 is a cross-sectional view illustrating another example of the exhaust heat recovery apparatus according to the fourth embodiment of the present invention and corresponding to FIG. 18. FIG. 19 is a cross-sectional view illustrating another example of the exhaust heat recovery apparatus according to the fourth embodiment of the present invention and corresponding to FIG. 18.

The best mode of the present invention will be described based on an embodiment shown in the drawings.
[Example 1]
1 to 11 show a first embodiment of the present invention.

  The exhaust heat recovery apparatus 1 according to the first embodiment is disposed in an exhaust system of a vehicle or the like that uses an internal combustion engine. An upstream exhaust pipe (not shown) is provided at an upstream side of an inflow port 1a. A downstream exhaust pipe (not shown) is connected to 1b. In addition, the figure shows a state when the exhaust heat recovery apparatus 1 is mounted on a vehicle, and the upper side of FIG. 1 is the top side and the lower side is the ground side.

  As shown in FIG. 4, the exhaust heat recovery apparatus 1 has a case 2, and a heat exchanger 3, a first flow path 4 passing through the heat exchanger 3, and the heat exchanger 3 are included in the case 2. A second flow path 5 that bypasses is provided. The second flow path 5 communicates with the upstream exhaust pipe and the downstream exhaust pipe.

  As shown in FIGS. 1 to 3, the case 2 includes a cylindrical main body 2 a and a reduced diameter portion 2 b provided on the downstream side of the main body 2 a. 3 to 6, the second flow path 5 is formed by a cylindrical tube having both ends open, and as shown in FIG. 5, the second flow path 5 is disposed at the center of the main body 2 a of the case 2. Yes.

  Two heat exchangers 3 are provided between the main body 2 a of the case 2 and the second flow path 5 so as to be located on both sides of the axis of the second flow path 5. As shown in FIG. 8, both the heat exchangers 3 and 3 are formed in the circular arc shape centering on the axial center of the main-body part 2a. The heat exchanger 3 has a medium flow path 3a through which a medium such as cooling water of a cooling system such as an internal combustion engine flows, and a fluid flow path 3b through which an exhaust gas fluid flows. As shown in FIGS. 1 to 5, the medium flow path 3a has a medium inlet 10a and a medium outlet 10b, and the medium inlet 10a and the medium outlet 10b are connected to a cooling system such as an internal combustion engine. . Thereby, in the heat exchanger 3, heat exchange can be performed between the medium and the exhaust gas.

  In a state where the exhaust heat recovery device 1 is installed in a vehicle or the like, as shown in FIGS. 1 and 4, the medium inlet 10 a is located below the second flow path 5, and the medium outlet 10 b is set in the second flow path 5. It is provided so that it may be located above. The medium flows in from the medium inlet 10a, branches into the left and right medium flow paths 3a, 3a at the branching section 10c, and flows upward in the medium flow paths 3a, 3a from the lower side to the upper side. It merges and is discharged from the medium outlet 10b.

  A cross section perpendicular to the axis of the main body 2a of the case 2 in the fluid flow path 3b is formed in an arc shape as shown in FIG. Further, as shown in FIG. 4, a plurality of fluid flow paths 3b are provided in parallel from the upstream side toward the downstream side. Although the number of the fluid flow paths 3b is arbitrary, in this embodiment, the left and right heat exchangers 3, 3 are each provided with four fluid flow paths 3b. Moreover, although the shape of the fluid flow path 3b is formed arbitrarily, it is preferable to form the outer edge part 3c of the inner peripheral surface in a curved surface shape.

  In the main body 2a of the case 2, a recovery space 13 for recovering condensed water generated when the exhaust gas performs heat exchange or the like in the fluid flow path 3b is provided in the lower part of the heat exchanger 3, and the heat exchanger 3 Is provided with a space 14 where exhaust gases flowing through the left and right fluid flow paths 3b merge. The fluid flow path 3b communicates with the recovery space 13 and the space 14, and the fluid flow path 3b, the recovery space 13 and the space 14 etc., the 1st flow path 4 is comprised. Thus, the heat exchangers 3 and 3 are provided on both sides in the case 2 and are not provided in the lower part of the case 2.

  As shown in FIGS. 4 and 6, a communication hole 18 is formed in the lower part of the second flow path 5, and the second flow path 5 communicates with the recovery space 13 through the communication hole 18 and a heat exchanger. 3 fluid flow paths 3b.

  A junction 21 where the second flow path 5 and the first flow path 4 merge is provided downstream of the communication hole 18. The second flow path 5 is formed with a first communication portion 24 that communicates the second flow path 5 and the merging portion 21. Further, the first flow path 4 is formed with a second communication portion 25 that communicates the space 14 of the first flow path 4 and the merging portion 21. The second communication part 25 is formed so as to be positioned above the first communication part 24. The second communication part 25 is formed in a housing 26 provided on the downstream side of the space 14. In the housing 26, only the upstream and downstream second communication portions 25 are opened, and the upstream opening communicates with the space 14.

  As shown in FIG. 9, a valve shaft 27 is provided on the upstream side of the second communication portion 25 so as to penetrate the left and right walls of the housing 26. As shown in FIGS. 4 and 5, the downstream end portion of the housing 26 is formed in an arc shape centering on the valve shaft 27, and the second communication portion 25 is formed in the arc portion.

  The valve shaft 27 is supported by bearings 29 and 29 provided on both sides in the housing 26. A bearing case 34 is provided on the outer periphery of the bearings 29 and 29 over the entire left and right direction of the first flow path 4. The housing 26 and the bearing case 34 prevent the exhaust gas in the first flow path 4 from coming into contact with the valve shaft 27.

  A pair of arm portions 30a, 30a formed on the swing arm type first valve body 30 is fixed to the valve shaft 27 protruding leftward and rightward in the axial direction from the housing 26, and the valve shaft 27 is rotated forward and backward. The first valve body 30 can be rotated forward and backward to open and close the second flow path 5. As shown in FIG. 10, the pair of arm portions 30 a and 30 a are provided in the axial direction of the valve shaft 27 so as to be longer than the length of the second communication portion 25 in the left-right direction. On the side surface of the second flow path 5 of the first valve body 30, a sealing material 30 b that contacts and separates from the first communication portion 24 is fixed.

  As shown in FIG. 9, the valve shaft 27 is provided so as to penetrate the case 2, and a seal member 28 is provided on the outer periphery of the valve shaft 27 and so as to penetrate the case 2. The seal member 28 has a labyrinth structure that prevents the exhaust gas from leaking out of the case 2.

  Conventionally, in an exhaust heat recovery apparatus in which a bearing is provided so as to penetrate the case, the bearing needs to suppress leakage of exhaust gas to the outside of the case in addition to supporting the valve shaft. Therefore, the bearing becomes large. On the other hand, in the present embodiment, the bearing 29 and the seal member 28 are configured as separate members, and the bearing 29 is provided in the case 2, so that the seal member 28 does not need a function of the bearing, and the exhaust gas is not generated. Since it suffices if leakage from the case 2 can be suppressed, the axial length of the seal member 28 can also be shortened. Further, since the bearing 29 only needs to consider the durability as a bearing, the diameter of the bearing 29 can be made smaller than the diameter of the bearing of the conventional exhaust heat recovery device, and the exhaust heat recovery device 1 can be reduced. It can be made smaller than the conventional exhaust heat recovery device.

  In the first valve body 30, a second valve body 31 is formed integrally with the first valve body 30 so as to be positioned between the arm portions 30 a and 30 a. The second valve body 31 is formed in an arc shape centered on the valve shaft 27, and the second valve body 31 is formed on the downstream side portion of the housing 26 by rotating the valve shaft 27 forward and backward. The second communication part 25 can be opened and closed by moving in the vertical direction along the part. The upstream side surface of the second valve body 31 may or may not be provided with a sealing material. In this embodiment, no sealing material is provided.

  The first valve body 30 and the second valve body 31 rotate integrally around the valve shaft 27, and when the first valve body 30 is opened as shown in FIG. Is closed to close the second communication portion 25. Also, as shown in FIG. 4, when the first valve body 30 is closed, the second valve body 31 is opened and the second communication portion 25 is opened. Is to be released.

  The junction 21 and the recovery space 13 communicate with each other through a discharge hole 23a formed at the lower end of the partition wall 23 provided between them, and the condensed water recovered in the recovery space 13 passes through the discharge hole 23a. After being discharged to the merging portion 21, it is discharged to the outside together with the exhaust gas.

  As shown in FIG. 11, a medium flow path 32 that guides the medium in the medium flow path 3 a to the heat receiving portion of a thermo-element 36 that is a temperature-actuated actuator provided outside the case 2 is provided above the heat exchanger 3. Is provided. Wax is stored in the heat receiving portion. Note that the heat receiving portion of the thermo element 36 may be provided directly in the medium flow path 3 a of the heat exchanger 3.

  A rod 38 urged toward the thermo element 36 by the urging member 37 is in contact with the distal end portion of the thermo element 36. When the wax in the thermo element 36 reaches a predetermined temperature or more, it thermally expands, its tip portion expands, and the rod 38 is pushed and moved by the tip portion, whereby the valve shaft 27 rotates, as shown in FIG. As described above, the first valve body 30 is opened to open the second flow path 5, and the second valve body 31 is closed to close the first flow path 4.

  Further, when the wax in the thermo element 36 becomes lower than a predetermined temperature, the wax contracts, the tip of the wax contracts, the rod 38 is urged by the urging member 37, and the valve shaft 27 rotates, so that FIG. As shown, the first valve body 30 is closed to close the second flow path 5, and the second valve body 31 is opened to open the first flow path 4.

  When the medium of the heat exchanger 3 is lower than a predetermined temperature, the second flow path 5 is closed and the first flow path 4 is opened as shown in FIG. After passing through the communication hole 18 from the second flow path 5, it passes through the recovery space 13, the fluid flow path 3 b of the heat exchanger 3, and the space 14, and flows from the second communication section 25 to the merging section 21. .

  The condensed water generated when the exhaust gas is heat-exchanged easily moves downward in the fluid flow path 3b by its own weight and is recovered into the recovery space 13, and then exhausted through the discharge hole 23a and the junction 21. The heat recovery apparatus 1 is discharged downstream. In addition, the fluid flow path 3b is arranged in parallel from the upstream side to the downstream side, and the condensate is easily discharged into the recovery space 13 by being formed in an arc shape that can flow in the vertical direction. When gas (bubbles) is generated due to boiling of the medium in the path 3a, the gas easily moves upward, and the gas in the medium flow path 3a is easily released upward.

  Further, when the outer edge 3c of the inner peripheral surface of the fluid flow path 3b is formed in a curved shape, the fluid always hits the outer edge 3c of the inner peripheral surface when the fluid flows in the fluid flow path 3b. The turbulent flow of the flowing exhaust gas is promoted, and the heat exchange efficiency of the heat exchanger 3 can be improved.

  On the other hand, when the medium of the heat exchanger 3 is at a predetermined temperature or higher, the second flow path 5 is opened and the first flow path 4 is closed as shown in FIG. Then, it passes through the second flow path 5 and flows to the junction 21.

  Since the heat receiving portion of the thermo-element 36 that is a temperature-actuated actuator comes into contact with the medium in the medium flow path 3a of the heat exchanger 3, the thermo-element responds immediately to the temperature of the medium in the heat exchanger 3. 36 operates and it can prevent that the medium temperature of the heat exchanger 3 becomes high too much.

  The second valve body 31 is disposed between the pair of arm portions 30a, 30a of the first valve body 30, and the first valve body 30 and the second valve body 31 are integrally formed, whereby the second valve body 31 is formed. Since 31 can be arranged in the rotation space of the first valve body 30, it can be made smaller than the conventional exhaust heat recovery device. Moreover, since the 2nd valve body 31 can be simultaneously manufactured in series with the material between the arm parts 30a and 30a of the 1st valve body 30 in the material which manufactures the 1st valve body 30, the material of the 1st valve body 30 The yield and the cost and man-hours can be reduced.

  By providing the recovery space 13 at the lower part of the heat exchanger 3, road surface interference of the heat exchanger 3 can be suppressed when the exhaust heat recovery device 1 is mounted at the lower part of the vehicle.

  Since the bearings 29 and 29 are provided and supported on the housing 26 in the case 2, it is only necessary to provide the sealing member 28 on the outer peripheral wall of the case 2 at the portion through which the valve shaft 27 penetrates. Since the length in the direction of the valve shaft 27 can be shortened, and the bearings 29 and 29 only need to ensure durability as a bearing, the diameter of the bearing 29 can be reduced, and the exhaust heat recovery device 1 can be reduced in size.

  Further, since the exhaust gas flows from the lower side to the upper side in the fluid flow path 3b and the medium flows from the lower side to the upper side in the medium flow path 3a, the high-temperature exhaust gas exchanges heat with the low-temperature medium. As in the prior art, the medium can be prevented from boiling.

  In addition, the first valve body 30 is opened to open the second flow path 5, and the second valve body 31 is closed to close the first flow path 4. When heat exchange is not required, the exhaust gas is prevented from flowing into the heat exchanger 3, and unlike the prior art, the reheating of the high-temperature medium is suppressed and the boiling of the medium is suppressed. Can do.

  Note that the temperature-actuated actuator may be bimetal or shape memory alloy, and the valve body may be rotated by changing the shape thereof.

  A valve system that opens and closes according to the flow rate of exhaust gas is well known in the exhaust system as a so-called variable valve, and an arbitrary mechanism can be used.

  Moreover, although the 1st valve body 30 and the 2nd valve body 31 were integrally formed, you may form the 1st valve body 30 and the 2nd valve body 31 separately.

[Example 2]
12 to 14 show a second embodiment of the present invention.

  In the first embodiment, the space 14 is provided in the upper part of the case 2 and the heat exchanger 3 is not provided in the upper part of the case 2, but this space 14 is not provided, as shown in FIGS. Moreover, the upper part of the left and right heat exchangers may be communicated with each other, and the heat exchanger 41 having the recovery space 13 may be formed in the lower part.

  As shown in FIG. 12, the heat exchanger 41 of the second embodiment is integrally formed in an arc shape in which a recovery space 13 portion provided at the lower end is cut out. The heat exchanger 41 has a medium flow path 41a through which a medium flows and a fluid flow path 41b through which exhaust gas flows. The medium that has flowed from the medium inlet 10a flows into the medium flow path 41a after passing through the branch portion 10c, and the medium that has passed through the medium flow path 41a is located above the medium flow path 41a. It is discharged from the communicating medium outlet 10b.

  As shown in FIG. 13, the cross section orthogonal to the axis of the main body 2a of the case 2 in the fluid flow path 41b is formed in an arc shape in which the recovery space 13 portion is cut out. Further, as shown in FIG. 12, a plurality of fluid flow paths 41b are provided in parallel from the upstream side toward the downstream side. Although the number of fluid flow paths 41b is arbitrary, in this embodiment, four fluid flow paths 41b are provided. Moreover, although the shape of the fluid flow path 41b is arbitrarily formed, it is preferable to form the outer edge portion 41c of the inner peripheral surface in a curved shape, and the outer edge portion 41c of the inner peripheral surface is thus formed in a curved shape. Therefore, when the fluid flows in the fluid flow path 41b, the fluid always hits the outer edge portion 41c of the inner peripheral surface, so that the turbulent flow of the exhaust gas flowing is promoted and the heat exchange efficiency of the heat exchanger 41 is improved. I can do it.

  As shown in FIGS. 12 to 14, a substantially semicircular discharge channel 45 is formed on the downstream side of the heat exchanger 41. The discharge channel 45 communicates with the collection space 13 and the housing 26.

  When the medium of the heat exchanger 41 is lower than the predetermined temperature, the second flow path 5 is closed and the first flow path 4 is opened as shown in FIG. After passing through the communication hole 18 from the second flow path 5, the heat flows through the recovery space 13 to the fluid flow path 41 b of the heat exchanger 41, and the exhaust gas flows upward through the discharge flow path 45. After the movement, the second communication part 25 of the housing 26 flows out to the joining part 21.

  On the other hand, when the medium of the heat exchanger 41 is equal to or higher than a predetermined temperature, the exhaust gas flows through the second flow path 5 to the junction 21 as in the first embodiment.

  Since other structures are the same as those of the first embodiment, the description thereof is omitted.

  Also in the second embodiment, the same operations and effects as the first embodiment are exhibited.

[Example 3]
15 and 16 show a third embodiment of the present invention.

  In the first and second embodiments, the communication hole 18 is provided in the lower part of the second flow path 5, but without the communication hole 18, as shown in FIGS. A branch portion 51 is provided to branch into the first flow path 4 and the second flow path 5, the medium branch section 10 c is not provided, and two medium inlets 10 a are provided on the left and right sides of the axis of the case 2, and directly from the medium inlet 10 a. Alternatively, the medium may flow into the medium flow path 41a.

  Since other structures are the same as those of the second embodiment, description thereof is omitted.

  Also in the third embodiment, the same operations and effects as those of the second embodiment are exhibited.

[Example 4]
17 to 20 show a fourth embodiment of the present invention.

  Fins may be provided in the fluid flow paths 3b and 41b of the exhaust heat recovery apparatus 1 of the first to third embodiments.

  For example, as shown in FIGS. 17 and 18, corrugated fins 51 may be provided in the fluid flow path 3b. The corrugated fin 51 is formed by bending a flat plate in the vertical direction of the exhaust heat recovery device 1, and is configured by a connecting surface 51c that connects the one end surface 51a, the other end surface 51b, and the one end surface 51a and the other end surface 51b. The axis of the fin 51 (exhaust gas flow direction) is formed in an arc shape curved along the axis of the fluid flow path 3b. One end surface 51a and the other end surface 51b of the corrugated fin 51 are provided so as to contact the inner peripheral surface of the fluid flow path 3b.

  Since other structures are the same as those in the first to third embodiments, description thereof is omitted.

  Also in the fourth embodiment, the same operations and effects as the first to third embodiments are exhibited.

  Furthermore, by providing the corrugated fins 51 in the fluid flow path 3b as described above, the heat exchange area between the exhaust gas and the medium can be increased as compared with the case where the corrugated fins 51 are not provided, and the exhaust gas The amount of heat received from the medium to the medium increases, and the heat exchange efficiency can be improved.

  Note that the shape and structure of the fins provided in the fluid flow paths 3b and 41b are arbitrary, and the offset fin 52 as shown in FIG. 19 or the axial direction of the fluid flow path 3b as shown in FIG. Polygonal fins 53 bent in multiple stages may be provided on substantially the entire axial direction of the fluid flow path 3b.

[Other Examples]
When the exhaust heat recovery apparatus 1 is mounted on a vehicle, the recovery space 13 may be positioned below. For example, the exhaust heat recovery apparatus 1 illustrated in FIG. It may be mounted on the vehicle in an inclined state.

  Further, if the exhaust gas and the medium circulate in the same direction in the heat exchangers 3 and 41 and a recovery space 13 for recovering condensed water is provided in the lower part of the heat exchangers 3 and 41, the heat exchanger 3, 41, the shape of the flow paths 3a, 3b, 41a, 41b, the structure and arrangement of the first flow path 4 and the second flow path 5 can be arbitrarily set. In addition, it is preferable to arrange the plurality of fluid flow paths 3b and 41b in the heat exchangers 3 and 41 in parallel from the upstream side to the downstream side.

  Further, in the above-described embodiment, the temperature operation actuator is used. However, any actuator can be used as long as it is an actuator without being limited to the temperature operation actuator. For example, a negative pressure actuator or an electric actuator can be used.

  In addition, the present invention is not limited to a heat recovery device (heat collector, oil warmer, etc.) in a narrow sense whose main purpose is heat recovery to a medium, but is also a heat exchanger (exhaust cooler or EGR) whose main purpose is cooling exhaust gas. Coolers etc.) are also included as heat recovery devices. Furthermore, the application target is not limited to an internal combustion engine such as a vehicle, but can be applied to an exhaust system of a device that generates any exhaust gas such as a general-purpose engine or a stationary combustion device.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and any design changes that do not depart from the spirit of the present invention are included in the present invention. It is.

DESCRIPTION OF SYMBOLS 1 Exhaust heat recovery apparatus 3,41 Heat exchanger 3b, 41b Fluid flow path 4 1st flow path 5 2nd flow path 13 Recovery space 18 Communication hole 30 1st valve body 31 2nd valve body 51,52,53 Fin

Claims (6)

In an exhaust system such as an internal combustion engine, a heat exchanger that performs heat exchange between exhaust gas and a medium, a first flow path through which the exhaust gas passes through the heat exchanger, and the exhaust gas bypasses the heat exchanger. A second flow path, a first valve body for opening and closing the second flow path, and a second valve body for opening and closing the first flow path,
The exhaust gas and the medium circulate in the same direction in the heat exchanger,
An exhaust heat recovery apparatus, wherein a recovery space for recovering condensed water is provided at a lower part of the heat exchanger in a vehicle-mounted state.   The exhaust heat recovery apparatus according to claim 1, wherein the heat exchanger has a plurality of fluid flow paths through which the exhaust gas flows, and the fluid flow paths are arranged in parallel from the upstream side to the downstream side. .   The exhaust heat recovery apparatus according to claim 1 or 2, wherein the exhaust gas flows from the lower side to the upper side in the heat exchanger in a vehicle-mounted state.   The second flow path is provided in a central portion of the case, a communication hole is provided in a lower part of the second flow path, the recovery space is provided below the second flow path, and the second flow is provided via the recovery space. The exhaust heat recovery apparatus according to claim 1, wherein the passage and the first flow path communicate with each other, and the first valve body is provided on the downstream side of the communication hole.   The exhaust heat recovery apparatus according to any one of claims 1 to 4, wherein the recovery space communicates with a downstream side of the heat exchanger in the first flow path or the second flow path. .   The exhaust heat recovery apparatus according to any one of claims 1 to 5, wherein fins are provided in the fluid flow path.

Images