JP5795923B2 - Heat exchanger - Google Patents

Description

  The present invention relates to a heat exchanger that warms water with the heat of exhaust gas.

  When the gas engine is operated, exhaust gas is generated. In order to efficiently use the heat energy of the exhaust gas, water is heated with the heat of the exhaust gas. A heat exchanger is used to warm water with exhaust gas (see, for example, Patent Document 1 (FIG. 3)).

Patent document 1 is demonstrated based on the following figure.
As shown in FIG. 14, the heat exchanger 200 includes a catalyst carrier 201 that purifies exhaust gas, a catalyst case 202 that holds the catalyst carrier 201, a first cylinder 203 that surrounds the catalyst case 202, It consists of a second cylinder 204 surrounding one cylinder 203 and a plurality of exhaust gas passage pipes 205 provided between the first cylinder 203 and the second cylinder 204.

  Exhaust gas generated in the gas engine is purified by flowing through the catalyst carrier 201 from the front side of the drawing toward the back side. The purified exhaust gas flows between the heat shielding cylinder 206 and the first cylinder 203 on the outer periphery of the catalyst case 202 from the back side to the front side of the drawing, and further, the exhaust gas passage pipe 205 is directed from the front side to the back side of the drawing. Flowing.

  On the other hand, water flows between the first cylinder 203 and the second cylinder 204 and on the outer periphery of the exhaust gas passage pipe 205. Heat of the exhaust gas is transferred to water through the exhaust gas passage tube 205 and the first cylinder 203.

By the way, both ends of the exhaust gas passage pipe 205 are fixed to plate-like members by welding. That is, it is necessary to perform welding for the number of exhaust gas passage pipes 205. On the other hand, if the number of exhaust gas passage pipes 205 is reduced in order to reduce the number of processing steps, the heat transfer area is reduced and the heat transfer efficiency is lowered.
It is desired to provide a heat exchanger with high heat transfer efficiency and a small number of processing steps.

JP 2000-257415 A

  An object of the present invention is to provide a heat exchanger that has high heat transfer efficiency and is easy to assemble.

The invention according to claim 1 is a substrate connected to an exhaust gas inlet through which exhaust gas is introduced, a catalyst case supported by the substrate and holding a catalyst carrier, and a first cylinder surrounding the catalyst case, A heat exchanger comprising a second cylinder surrounding the first cylinder and a third cylinder enclosing the second cylinder, the outer circumferential surface of the catalyst case and the inner circumference of the first cylinder The first gas flow path through which the exhaust gas that has passed through the catalyst carrier flows toward the base is formed between the outer peripheral surface of the first cylindrical body and the inner peripheral surface of the second cylindrical body. A space between the outer peripheral surface of the second cylinder and the inner peripheral surface of the third cylinder is exhaust gas that has passed through the first gas flow path. with flowing toward the formed in the bottom of the body exhaust gas outlet is a second gas flow path is discharged to the outside, the second gas flow path And communicates with the first gas flow channel by the communicating path provided on the base side than the end of the waterway, the substrate includes a first member connected to the inlet port, the first member A hollow body formed by joining with a second member arranged on the downstream side of the base body, the inner periphery of the base is the communication path, the second gas flow path and the communication path, The plurality of communication holes formed in the second member communicate with each other, or the first gas flow path and the communication path communicate with each other through a plurality of communication holes formed in the first cylindrical body. The plurality of communication holes are formed such that the flow passage area increases as the distance from the exhaust gas discharge port increases .

In the invention according to claim 2, a base connected to an exhaust gas inlet into which exhaust gas is introduced, a catalyst case supported by the base and holding a catalyst carrier, and a first cylinder surrounding the catalyst case, A heat exchanger comprising a second cylinder surrounding the first cylinder and a third cylinder enclosing the second cylinder, the outer circumferential surface of the catalyst case and the inner circumference of the first cylinder The first gas flow path through which the exhaust gas that has passed through the catalyst carrier flows toward the base is formed between the outer peripheral surface of the first cylindrical body and the inner peripheral surface of the second cylindrical body. A space between the outer peripheral surface of the second cylinder and the inner peripheral surface of the third cylinder is exhaust gas that has passed through the first gas flow path. A second gas flow path that flows toward an exhaust gas discharge port formed at the bottom of the body and is discharged to the outside. The first cylinder is connected to the first gas flow path by a communication path provided on the base side from the end of the water channel, and the central axis of the second cylinder is concentrically arranged with the first cylinder and the The exhaust tube is disposed so as to be away from the water discharge port formed in the second tube with respect to the central axis of the third tube, and the exhaust gas discharge port is disposed in the first tube relative to the water discharge port. The cylindrical body and the third cylindrical body are disposed so as to sandwich the central axis .

  The invention according to claim 3 is characterized in that the second member is formed integrally with either the end of the first cylinder or the end of the second cylinder.

  In the invention which concerns on Claim 4, the 3rd cylinder is joined by the same junction part as the 1st member and the 2nd member, It is characterized by the above-mentioned.

  In the invention which concerns on Claim 5, the 2nd member is integrally formed in the edge part of the 3rd cylinder, It is characterized by the above-mentioned.

  In the invention according to claim 1, the second cylinder is surrounded by the third cylinder, and the second exhaust gas flow path is formed between the second cylinder and the third cylinder. Since the second cylinder is surrounded by the third cylinder and the space between the second cylinder is an exhaust gas flow path, the exhaust gas can flow over the entire outer peripheral surface of the second cylinder. Since exhaust gas flows through the entire outer peripheral surface of the second cylinder, a large heat transfer area can be secured. A large heat transfer area enables efficient heat exchange.

On the other hand, the third cylinder surrounding the second cylinder is one member. The third cylinder is joined after the second cylinder is surrounded by the third cylinder. If only one third cylinder is welded, the number of processing steps is significantly reduced as compared with the case of joining a plurality of exhaust gas passage pipes.
That is, the heat exchanger according to the present invention has high heat transfer efficiency and a small number of processing steps.

In addition, by eliminating the exhaust gas passage pipe, the width of the water channel between the first cylinder and the second cylinder can be set according to the flow rate of water. Since the width of the water channel can be determined by the flow rate of water, the heat exchanger can be downsized as compared with the case where the exhaust gas passage pipe is used.
In addition, the inner periphery of the base formed in a hollow shape is a communication path. By using the inner periphery of the base body as a communication path, the heat exchanger can be reduced in size and the number of parts can be reduced as compared with the case where a separate communication path is formed.
In addition, the exhaust gas can be caused to flow through the entire second gas flow path by narrowing the flow path area at a part where the exhaust gas easily flows and widening the flow path area at a part where the exhaust gas hardly flows. By flowing the exhaust gas throughout, the heat exchange efficiency can be further increased.

In the invention according to claim 2, the second cylinder is surrounded by the third cylinder, and the second exhaust gas flow path is formed between the second cylinder and the third cylinder. Since the second cylinder is surrounded by the third cylinder and the space between the second cylinder is an exhaust gas flow path, the exhaust gas can flow over the entire outer peripheral surface of the second cylinder. Since exhaust gas flows through the entire outer peripheral surface of the second cylinder, a large heat transfer area can be secured. A large heat transfer area enables efficient heat exchange. On the other hand, the third cylinder surrounding the second cylinder is one member. The third cylinder is joined after the second cylinder is surrounded by the third cylinder. If only one third cylinder is welded, the number of processing steps is significantly reduced as compared with the case of joining a plurality of exhaust gas passage pipes. That is, the heat exchanger according to the present invention has high heat transfer efficiency and a small number of processing steps. In addition, by eliminating the exhaust gas passage pipe, the width of the water channel between the first cylinder and the second cylinder can be set according to the flow rate of water. Since the width of the water channel can be determined by the flow rate of water, the heat exchanger can be downsized as compared with the case where the exhaust gas passage pipe is used.
Furthermore, the flow channel area on the water discharge port side was narrowed, and the flow channel area at the site away from the water discharge port was widened. Reduce the area of the flow path that passes through the shortest distance from the water inlet to the water outlet. On the other hand, the channel area of the part far from the water discharge port and difficult to flow of water is expanded. Thereby, water can be made to flow more uniformly over the entire circumference between the first cylinder and the second cylinder. By flowing water more uniformly, water can flow smoothly and the efficiency of heat exchange can be improved.
In addition, since the central axis is shifted, the flow area of the second gas flow path formed between the second cylinder and the third cylinder is reduced to the exhaust gas discharge pipe side (exhaust gas discharge port). Narrow at the side) and wide at the site away from the exhaust gas exhaust pipe. Reduce the area of the flow path that passes through the shortest distance to the exhaust gas discharge pipe. On the other hand, the flow passage area of the part far from the exhaust gas discharge pipe and difficult to flow the exhaust gas is expanded. Thereby, exhaust gas can be flowed more uniformly over the perimeter between a 2nd cylinder and a 3rd cylinder. By flowing the exhaust gas more uniformly, the exhaust gas can flow smoothly and the efficiency of heat exchange can be increased.

  In the invention which concerns on Claim 3, the 2nd member is integrally formed in either the edge part of a 1st cylinder, or the edge part of a 2nd cylinder. By forming the first cylinder or the second cylinder integrally with the second member, the number of parts can be reduced and the number of assembling steps can be reduced.

  In the invention which concerns on Claim 4, the 3rd cylinder is joined by the same junction part as the 1st member and the 2nd member. By combining the joining portions in one place, the first member, the second member, and the third cylindrical body can be joined by a single joining operation. By joining together, assembly man-hours can be further reduced.

  In the invention which concerns on Claim 5, the 2nd member is integrally formed in the edge part of the 3rd cylinder. By forming the third cylindrical body integrally with the second member, it is possible to reduce the number of parts and the assembly man-hours.

It is a perspective view of the heat exchanger which concerns on this invention. 1 is a cross-sectional view of a heat exchanger according to Embodiment 1. FIG. It is a disassembled perspective view of the base | substrate and 1st case which concern on this invention. It is an expanded view of a 1st case. It is a bottom view of a base. FIG. 6 is a sectional view taken along line 6-6 of FIG. It is explanatory drawing from introduction of exhaust gas to passing through a catalyst carrier. It is explanatory drawing until it is discharged | emitted after exhaust gas passes a 1st gas flow path. It is a figure which compares the heat exchanger which concerns on this invention, and a comparative example. It is sectional drawing of the heat exchanger which concerns on Example 2. FIG. It is sectional drawing of the heat exchanger which concerns on Example 3. FIG. It is sectional drawing of the heat exchanger which concerns on Example 4. FIG. It is sectional drawing of the heat exchanger which concerns on Example 5. FIG. It is a figure explaining the basic composition of the conventional technology.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.

First, Embodiment 1 of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the heat exchanger 10 includes a base 11 and a plurality of cases (details will be described later) supported by the base 11 and through which exhaust gas or water flows.
An exhaust gas inlet 12 for introducing exhaust gas into the base 11 is formed. A flange 13 for attaching the heat exchanger 10 is joined to the exhaust gas inlet 12.
The detail of the heat exchanger 10 is demonstrated with the following figure.

  As shown in FIG. 2, the heat exchanger 10 includes a base 11, a cylindrical catalyst carrier 15 that is supported by the base 11 and purifies exhaust gas, and a catalyst case 16 that surrounds and holds the catalyst carrier 15, A first case 17 surrounding the catalyst case 16, a second case 18 surrounding the first case 17 and supported by the lower surface of the base 11, and a side surface of the base 11 surrounding the second case 18 A third case 19 supported by the bottom case, an exhaust gas discharge pipe 22 connected to the bottom end of the third case 19 for discharging exhaust gas, and a water penetrating toward the center of the bottom surface of the second case 18. And a water discharge pipe 24 which is joined to the upper end of the side surface of the second case 18 and discharges water.

  The base 11 includes a first member 26 to which the catalyst case 16 is bonded to the lower surface, and a second member 27 to be bonded to the first member 26. The base 11 is formed in a hollow shape by superimposing the first member 26 and the second member 27. By forming it in a hollow shape, exhaust gas can flow into the inside of the substrate 11.

  The first case 17 joined to the second member 27 includes a cylindrical first cylinder 28 surrounding the catalyst case 16 and a lower end of the catalyst carrier 15 joined to the lower end of the first cylinder 28. And a first bottom portion 29 covering the same. The 1st case 17 can be manufactured by welding the 1st steel cylinder 28 and the 1st bottom part 29 which were shape | molded by press molding.

  The second case 18 is integrally formed at the lower end of the second cylinder 31 and the second cylinder 31 that is welded to the lower surface of the second member 27 and surrounds the first cylinder 28. And a second bottom portion 32 that closes the lower end of the second bottom portion 32.

  The third case 19 is formed integrally with the third cylinder 33 that is joined to the side surface of the second member 27 and surrounds the second cylinder 31, and the lower end of the third cylinder 33. And a third bottom portion 34 that closes the lower end of the first bottom portion 34.

  The first member 26 constituting the base 11 includes a bottom 36 and a wall portion 37 extending from the periphery of the bottom 36 toward the second member 27. An exhaust gas inlet 12 for introducing exhaust gas is formed from an opening formed in the center of the bottom 36. The exhaust gas inlet 12 is formed integrally with the first member 26.

  The second member 27 includes a bottom 38 and a wall 39 that rises from the periphery of the bottom 38 toward the first member 26. An opening is formed in the center of the bottom 38, and the first cylinder 28 is joined to the opening. Further, a plurality of communication holes 42 a and 42 e that communicate the inside of the base body 11 and the inside of the third cylinder 33 are formed in a portion of the bottom 38 on the outer side in the circumferential direction than the second cylinder 31.

  The first member and the second member may employ a structure in which both the bottom and the wall are overlapped with a member having only the bottom and a member having the bottom and the wall superimposed on each other. That is, any shape can be adopted as long as it is hollow. In addition, it is possible to change the shape as appropriate for easy welding, such as welding after extending the wall portions in the outer peripheral direction, or to butt weld each other with the wall portions it can.

An exhaust gas restricting portion 28 a that protrudes from the first cylindrical body 28 toward the catalyst case 16 and restricts the flow path of the exhaust gas when the tip contacts the catalyst case 16 is formed. That is, the exhaust gas flows meandering so as to avoid the portion where the exhaust gas restricting portion 28a is formed. Details will be described later.
A bulging portion 29 a that bulges toward the catalyst carrier 15 is formed at the center of the first bottom portion 29.

The second cylinder 31 includes a general portion 31a whose lower end is closed by the second bottom portion 32, and a diameter-expanded portion 31b to which the diameter is increased from the general portion 31a and the water discharge pipe 24 is joined. A water discharge port 31c to which the water discharge pipe 24 is joined is formed in the enlarged diameter portion 31b.
The second bottom portion 32 has a water introduction port 32a through which water is introduced at the center. The water introduction pipe 23 is connected to the water introduction port 32a.

  The third cylinder 33 includes a general portion 33a whose lower end is closed by the third bottom portion 34, and a diameter-expanded portion 33b whose diameter is increased from the general portion 33a. A water discharge opening 33c through which the water discharge pipe 24 passes is formed in the enlarged diameter portion 33b. The water discharge opening 33c is formed in accordance with the position where the water discharge port 31c is formed.

  The third bottom portion 34 is formed with a stepped portion 34a that protrudes toward the second bottom portion 32 and contacts the bottom portion of the second bottom portion 32, and a water introduction opening for allowing the water introduction pipe 23 to pass through the center of the stepped portion 34a. 34b is formed. Further, an exhaust gas discharge port 34c for discharging exhaust gas is formed at the end of the third bottom portion 34, and the exhaust gas discharge pipe 22 is joined to the exhaust gas discharge port 34c.

  The water introduction opening 34b is formed in accordance with the position where the water introduction port 32a is formed. When the stepped portion 34 a contacts the second bottom portion 32, the strength of the second bottom portion 32 can be increased. Since the water introduction port 32a is provided at a portion where the strength of the second bottom portion 32 is increased and the water introduction tube 23 is supported, the water introduction tube 23 can be supported with high strength.

The central axis 45 of the general portion 31a of the second cylindrical body 31 is shifted with respect to the central axis 44 of the catalyst carrier 15 in a direction away from the water discharge port 31c.
On the other hand, the centers of the exhaust gas inlet 12, the first cylindrical body 28, and the third cylindrical body 33 coincide with the central axis 44 of the catalyst carrier 15. The reason why the central axis 45 of the second cylinder 31 is shifted will be described later.

  Between the outer peripheral surface of the catalyst case 16 and the inner peripheral surface of the first cylindrical body 28, a first gas passage 46 through which exhaust gas flows upward in the drawing, the outer periphery of the first cylindrical body 28, and the second cylindrical body 31. Between the outer circumference of the water channel 47 and the outer circumference of the second cylinder 31 and the inner circumference of the third cylinder 33, the exhaust gas flows downward in the figure. The inside of the base 11 formed in the second gas flow path 48 and the hollow shape is a communication path 49 that connects the first gas flow path 46 and the second gas flow path 48.

That is, the second gas flow path 48 is connected to the first gas flow path 46 by a communication path 49 provided closer to the base body 11 than the upper end portion of the water path 47.
The inner periphery of the base body 11 formed in a hollow shape is a communication path 49. By using the inner periphery of the base 11 as the communication path 49, the heat exchanger 10 can be reduced in size and the number of parts can be reduced as compared with the case where a separate communication path is formed.
Details of the first case 17 will be described with reference to the next figure.

  As shown in FIG. 3, a plurality of exhaust gas restricting portions 28 a are formed in the first cylinder 28. By being formed in a part of the cylindrical first cylindrical body 28, the exhaust gas restricting portion 28a has a substantially C shape in plan view. Each of these exhaust gas regulating portions 28a is formed in the same shape, and is formed at two places at the same height in the height direction. When the two exhaust gas restricting portions 28a formed at the same height are arranged in one stage, such exhaust gas restricting portions 28a are formed in four stages.

  Although the number of stages of the exhaust gas restricting portion 28a is arbitrary, it is desirable that the exhaust gas restricting portion 28a be arranged as described in the next figure. The first cylinder 28 will be described in more detail with reference to the next drawing.

  FIG. 4 is a view of the first cylindrical body 28 developed and viewed from the inside, and the exhaust gas restricting portion 28a protrudes toward the front side of the drawing. The lengths of the passages 28b between the restricting portions that are formed between the exhaust gas restricting portions 28a and 28a in the same stage (left and right in the drawing) and through which the exhaust gas passes are all α.

  A midpoint between the restricting portion passages 28b and 28b formed in the same step is defined as C1. The length P between the two middle points C1 is equal to the length of the half circumference of the first cylinder 28. That is, the midpoint C1 of the inter-regulator passage 28b and the midpoint C1 of the inter-regulator passage 28b are formed 180 degrees apart. The exhaust gas restricting portions 28a formed 180 degrees apart are formed symmetrically with the central axis (FIG. 1, reference numeral 44) of the first cylinder 28 interposed therebetween.

  The midpoint C1 of the inter-regulator passage 28b coincides in the height direction with the midpoint C2 of the exhaust gas restrictor 28a in the adjacent step (the vertical direction in the drawing). That is, they are arranged 90 degrees out of phase with respect to the exhaust gas restricting portion 28a at the adjacent stage.

  The length β of the exhaust gas restricting portion 28a, the length (1/2) α from one end of the exhaust gas restricting portion 28a to the middle point C1 of the passage 28b between the restricting portions, and the distance between the other end of the exhaust gas restricting portion 28a and the restricting portion When the length (1/2) α to the midpoint C1 of the passage 28b is set, the length obtained by adding these is β + (1/2) α · 2 = P is one pitch. In this case, one pitch is 180 °, and it can be said that the exhaust gas restricting portion 28a is arranged 90 ° out of phase with the exhaust gas restricting portion 28a of the adjacent stage.

One pitch is 120 °, and the phase is shifted by 60 ° with respect to the adjacent exhaust gas restricting portion. One pitch is 90 °, and the phase can be shifted by 45 ° with respect to the adjacent exhaust gas restricting portion.
In order to suppress the influence of pressure loss, the communication hole has an opening area so that the volume flow rate at the exhaust gas temperature when passing through the communication hole does not become a resistance against the cross-sectional area of the gas flow path before and after the communication hole. Value is set.
Details of the communication holes (FIG. 2, reference numerals 42a and 42e) opened in the second member (FIG. 2, reference numeral 27) will be described with reference to the following drawings.

  As shown in FIG. 5, a plurality of types of communication holes 42 a to 42 e are opened in the bottom 38 of the second member 27. The communication holes 42a to 42e have different sizes, the smallest communication hole 42a has a circular shape, and the other communication holes 42b to 42e have an oval shape. The sizes of the communication holes 42a to 42e increase in alphabetical order from a to e. The maximum communication hole 42e is formed with the central axis 44 interposed therebetween with respect to the minimum communication hole 42a.

  The smallest communication hole 42a is disposed above the exhaust gas discharge port (FIG. 2, symbol 34c). If all the communication holes have the same size, a large amount of exhaust gas flows from the communication holes arranged above the exhaust gas discharge port.

  The size of the communication holes 42a to 42e was increased and the flow path area was increased as the distance from the exhaust gas discharge port was increased. The exhaust gas can flow through the entire second gas flow channel (FIG. 2, reference numeral 48) by narrowing the flow channel area at the part where the exhaust gas easily flows and widening the flow channel area at the part where the exhaust gas hardly flows. . By flowing the exhaust gas throughout, the heat exchange efficiency can be further increased.

In addition, the shape of a communicating hole is arbitrary and these combinations can also be changed suitably. For example, a plurality of holes having the same size can be formed and adjusted according to the arrangement of these holes.
Details of the second gas flow path (FIG. 2, reference numeral 48) and the water channel (FIG. 2, reference numeral 47) will be described with reference to the next drawing.

  As shown in FIG. 6, the catalyst carrier 15, the catalyst case 16, the first cylinder 28, and the third cylinder 33 are arranged concentrically around the central axis 44. On the other hand, the central axis 45 of the second cylindrical body 31 is shifted from the central axis 44 in a direction away from the water discharge port 31c. By shifting the central axes 44 and 45 by t, the channel area of the water channel 47 on the water discharge port 31c side is narrow (σ1), and the channel area at a part away from the water discharge port 31c is wide (σ2). Forming.

  Further, the center axis 44 of the third cylinder 33 is shifted in a direction away from the exhaust gas discharge pipe 22 (exhaust gas discharge port) with respect to the center axis 45 of the second cylinder 31. As a result, the flow area of the second gas flow path 48 on the exhaust gas discharge pipe 22 side is narrow (σ3), and the flow area of the part away from the exhaust gas discharge pipe 22 is wide (σ4).

  An exhaust gas discharge pipe 22 (exhaust gas discharge port) is disposed with the central shaft 44 sandwiched with respect to the water discharge port 31c. By disposing the central axis 44 therebetween, it is possible to satisfy σ1 <σ2 and σ3 <σ4.

  As shown by the arrow (1) in FIG. 7, the exhaust gas introduced from the exhaust gas inlet 12 first flows in the catalyst carrier 15 toward the lower side of the drawing. As indicated by the arrow (2), the exhaust gas is purified by flowing through the catalyst carrier 15. The exhaust gas that has flowed through the catalyst carrier 15 flows from the lower end of the catalyst carrier 15 toward the first gas flow path 46.

  By forming the bulging portion 29 a in the first bottom portion 29, the exhaust gas can flow smoothly between the catalyst case 16 and the first cylindrical body 28. That is, the bulging portion 29a serves as a guide for guiding the flow of exhaust gas.

  As shown in FIG. 8, the purified exhaust gas passes through the first gas passage 46 from the bottom to the top of the drawing. The exhaust gas bypasses the exhaust gas restricting portion 28a and flows upward. The exhaust gas that has passed through the first gas flow path 46 reaches the inside of the substrate 11.

  The exhaust gas that has reached the inside of the base 11 passes through the communication passage 49 and flows downward from the communication holes 42a and 42e. The exhaust gas that has passed through the communication holes 42a and 42e passes through the second gas passage 48 downward in the drawing. The exhaust gas that has flowed to the lower end of the second gas passage 48 is discharged to the outside through the exhaust gas discharge port 34c.

  On the other hand, the water introduced from the water inlet 32a passes through the water channel 47 upward in the drawing. The water that flows upward is discharged to the outside from the water discharge port 31c. The water is warmed through the first bottom portion 29 by the heat of the exhaust gas discharged downward from the catalyst carrier 15, and through the first cylinder 28 by the heat of the exhaust gas passing through the first gas flow path 46. And heated by the heat of the exhaust gas passing through the communication passage 49 via the second member 27 and heated by the heat of the exhaust gas passing through the second gas passage 48 via the second cylinder 31. .

  Since the second cylinder 31 is surrounded by the third cylinder 33 and this space is used as an exhaust gas flow path (second gas flow path 48), the exhaust gas can flow over the entire outer peripheral surface of the second cylinder 31. it can. Since exhaust gas flows through the entire outer peripheral surface of the second cylinder 31, a large heat transfer area can be secured. A large heat transfer area enables efficient heat exchange.

  On the other hand, the third cylinder 33 surrounding the second cylinder 31 is one member. The third cylinder 33 is joined after the second cylinder 31 is surrounded by the third cylinder 33. Compared to the case of joining a plurality of exhaust gas passage pipes, the number of man-hours can be reduced and the assembling work becomes easy.

  A bulging portion 29 a is formed in the first bottom portion 29. By forming the bulging part 29a, it can be made to flow by a jet and the flow path area of water can be taken large. By increasing the water flow path area, the flow rate of water can be increased. A large flow rate of water prevents a rapid rise in water temperature and prevents water from boiling. By preventing the water from boiling, water can flow smoothly and heat can be exchanged efficiently.

  In addition, a water inlet 32a is formed below the bulging portion 29a, and water is introduced toward the bulging portion 29a. That is, the water before being heated by the exhaust gas is caused to flow toward the bulging portion 29a. Since the exhaust gas having a high temperature that has just passed through the catalyst carrier 15 flows in the vicinity of the bulging portion 29a, heat can be efficiently recovered and the occurrence of boiling can be more reliably prevented.

  Furthermore, the flow channel area on the water discharge port 31c side was narrowed, and the flow channel area at a site away from the water discharge port 31c was widened (see also FIG. 6). By reducing the area of the flow path (left side of the drawing) that passes through the shortest distance from the water inlet 32a to the water outlet 31c, the flow rate of water that passes through the shortest distance is reduced. On the other hand, the flow area of the part (right side of the drawing) that is far from the water discharge port 31c and is difficult to flow is increased, and the flow rate of water is increased. Thereby, water can be flowed more uniformly over the entire circumference between the first cylinder 28 and the second cylinder 31. By flowing water more uniformly, water can flow smoothly and the efficiency of heat exchange can be improved.

  In addition, the flow path area of the second gas flow path 48 formed between the second cylindrical body 31 and the third cylindrical body 33 by shifting the central axis (FIG. 2, reference numerals 44 and 45). Can be narrow at the exhaust gas exhaust pipe 22 side (exhaust gas exhaust port 34c side) and wide at a part away from the exhaust gas exhaust pipe 22 (left side in the drawing). By reducing the area of the flow path that passes through the shortest distance to the exhaust gas discharge pipe 22, the flow rate of the exhaust gas that passes through the shortest distance is reduced. On the other hand, the flow area of the part far from the exhaust gas discharge pipe 22 and difficult to flow the exhaust gas is expanded, and the flow rate of the exhaust gas is increased. Thereby, exhaust gas can be made to flow more uniformly over the entire circumference between the second cylinder 31 and the third cylinder 33. By flowing the exhaust gas more uniformly, the exhaust gas can flow smoothly and the efficiency of heat exchange can be increased.

  As shown in the comparative example of FIG. 9A, the heat exchanger 210 warms water by the exhaust gas passing through the gas flow path 211 and the exhaust gas passing through the exhaust gas passage pipe 213 disposed in the water path 212. It is done. The diameter D1 of the heat exchanger 210 is set to a size that allows water to flow smoothly in consideration of the diameter D2 of the exhaust gas passage pipe 213. That is, the width of the water channel 212 is set to be larger than D2 at least.

On the other hand, as shown in the embodiment of FIG. 9B, in the heat exchanger 10 according to the present invention, water is warmed by the exhaust gas passing through the first and second gas flow paths 46 and 48. The width of the water channel 47 of the heat exchanger 10 is set to a width that allows water to flow smoothly. The width of the second gas channel 48 is set to a width that allows the exhaust gas to flow smoothly. Since the second gas channel 48 surrounds the entire circumference of the water channel 47, a large channel area can be ensured even with a small width. That is, the second gas passage 48 can flow the exhaust gas sufficiently smoothly even if the width is small. For this reason, the diameter D3 of the heat exchanger 10 can be made smaller than the diameter D1 of the heat exchanger 210 which concerns on a comparative example. That is, the heat exchanger 10 can be downsized as compared with the case where the exhaust gas passage pipe 213 is used.
Another embodiment will be described in detail in the following figures.

Next, a second embodiment of the present invention will be described with reference to the drawings.
FIG. 10 shows a cross-sectional configuration of the heat exchanger according to the second embodiment, corresponding to FIG.
As shown in FIG. 10, in the heat exchanger 60, the second member 62 constituting the base body 61 is formed integrally with the first case 63. More specifically, the second member 62 is formed integrally with the end portion of the first cylindrical body 64. The first cylinder 64 is formed with an exhaust gas restricting portion 64a and a passage 64b between restricting portions.

  The effect of the present invention can also be obtained when the second member 62 is formed integrally with the first cylindrical body 64. That is, it can be said that the heat exchanger 60 has high heat transfer efficiency and can be easily assembled.

In addition, since the first cylindrical body 64 is formed integrally with the second member 62, the number of parts can be reduced and the number of assembly steps can be reduced.
Still another embodiment will be described with reference to the following figure.

Next, Embodiment 3 of the present invention will be described with reference to the drawings.
FIG. 11 shows a cross-sectional configuration of the heat exchanger according to the third embodiment, corresponding to FIG.
As shown in FIG. 11, in the heat exchanger 70, the third case 75 is joined at the same joint portion 74 as the first member 72 and the second member 73 constituting the base 71. A second case 76 is integrally formed with the second member 73, and the first case 77 is joined to the second case 76.

  More specifically, the second member 73 is formed integrally with the end portion of the second cylinder 81. The third cylinder 82 is joined at the same joining portion 74 as the first member 72 and the second member 73.

  The effect of the present invention can also be obtained when such a heat exchanger 70 is used. That is, it can be said that the heat exchanger 70 has high heat transfer efficiency and can be easily assembled.

In addition, since the second cylinder 81 is formed integrally with the second member 73, the number of parts can be reduced and the number of assembly steps can be reduced.
Furthermore, the 1st member 72, the 2nd member 73, and the 3rd cylinder 82 can be joined by one joining operation | work by putting together the junction part 74 in one place. By joining together, assembly man-hours can be further reduced.

  The first member 72 and the exhaust gas inlet 84 are connected via an arc-shaped connecting portion 85. By forming the connecting portion 85 in an arc shape, the flow of the exhaust gas can be smoothly spread, and the exhaust gas can be sent to the entire surface of the catalyst carrier 15. In addition, the circular arc shape can prevent stress due to the heat of the exhaust gas from concentrating on the connecting portion 85. Furthermore, the number of parts can be reduced by integrally forming the exhaust gas introduction port 84, the connecting portion 85 that spreads the introduced exhaust gas, and the first member 72 (base 71).

  In the first case 77, a first cylindrical body 86 and a first bottom portion 87 are integrally formed. The distal end portion 86c of the first cylinder 86 is extended toward the second cylinder 81 and brought into contact with the inner peripheral surface of the second cylinder 81, and then the first cylinder 86 is joined to the second cylinder 81. ing. Moreover, the bulging part 87a formed in the 1st bottom part 87 is formed in cross-sectional view trapezoid shape. 86a is an exhaust gas restricting portion, and 86b is a passage between restricting portions.

  The 2nd cylinder 81 consists only of the general part 81a, and the water discharge port 81c is formed in this general part 81a. The water inlet 88 a of the second bottom portion 88 is formed in a stepped portion 88 b that protrudes toward the third case 75.

The 3rd cylinder 82 consists only of the general part 82a, and the water discharge opening part 82c is formed in this general part 82a. A stepped portion 89 a, a water introduction opening 89 b, and an exhaust gas discharge port 89 c are formed in the third bottom portion 89, and the stepped portion 89 a is in contact with the stepped portion 88 b of the second bottom portion 88.
Still another embodiment will be described with reference to the next figure.

Next, a fourth embodiment of the present invention will be described with reference to the drawings.
FIG. 12 shows a cross-sectional configuration of the heat exchanger of the fourth embodiment, corresponding to FIG.
As shown in FIG. 12, in the heat exchanger 90, a second member 92 that constitutes the base 91 and a third case 93 are integrally formed. More specifically, the second member 92 is formed integrally with the end of the third cylinder 94.

The effect of the present invention can also be obtained when the second member 92 is formed integrally with the third cylinder 94. That is, it can be said that the heat exchanger 90 has high heat transfer efficiency and can be easily assembled.
In addition, since the third cylindrical body 94 is formed integrally with the second member 92, the number of parts can be reduced and the number of assembly steps can be reduced.

  The first cylindrical body 96 constituting the first case 95 has an extended joint portion 96 c extending toward the first member 26, and the extended joint portion 96 c is joined to the lower surface of the first member 26. ing. Communication holes 96d and 96h that allow the first gas flow path 46 and the communication path 49 to communicate with each other are formed in a part of the extended joint portion 96c. Reference numeral 96a denotes an exhaust gas restricting portion, and 96b denotes a passage between restricting portions. The communication holes 96d and 96h are holes having different sizes, and the details are as described in FIG.

  The second cylinder 98 constituting the second case 97 is composed only of the general part 98a, and a water discharge port 98c is formed in the general part 98a. Such a second cylinder 98 is joined to the first cylinder 96.

The 3rd cylinder 94 consists only of the general part 94a, and the water discharge opening part 94c is formed in the general part 94a.
Still another embodiment will be described with reference to the following figure.

Next, a fifth embodiment of the present invention will be described with reference to the drawings.
FIG. 13 shows a cross-sectional configuration of the heat exchanger of Example 5, corresponding to FIG.
As shown in FIG. 13, in the heat exchanger 100, a second member 92 that constitutes the base 91 and a third case 93 are integrally formed. More specifically, the second member 92 is formed integrally with the end of the third cylinder 94.

The effect of the present invention can also be obtained when the second member 92 is formed integrally with the third cylinder 94. That is, it can be said that the heat exchanger 100 has high heat transfer efficiency and can be easily assembled.
In addition, since the third cylindrical body 94 is formed integrally with the second member 92, the number of parts can be reduced and the number of assembly steps can be reduced.

  The 2nd cylinder 102 which comprises the 2nd case 101 consists of only the general part 102a, and the water discharge port 102c is formed in this general part 102a. The water discharge port 102 c extends in an inclined state toward the third case 93. Since the water discharge port 102 c is inclined, the water discharge pipe 104 to be inserted into the water discharge port 102 c is inserted with an inclination with respect to the third case 93. By inclining the water discharge pipe 104 with respect to the third case 93, when welding the water discharge pipe 104 to the water discharge port 102c, the tip of the welding torch can be easily exposed.

  The heat exchanger according to the present invention can be applied to a cogeneration apparatus and other uses. In the heat exchanger according to the present invention, it is desirable to use cooling water as water, and an optimum type of medium can be used depending on the application.

  The heat exchanger of the present invention is suitable for a cogeneration apparatus.

  10, 60, 70, 90, 100 ... heat exchanger, 11, 61, 71, 91 ... base, 12, 84 ... exhaust gas inlet, 15 ... catalyst carrier, 16 ... catalyst case, 26, 72 ... first Member, 27, 62, 73, 92 ... second member, 28, 64, 86, 96 ... first cylinder, 31, 81, 98, 102 ... second cylinder, 33, 82, 94 ... third cylinder 46, first gas channel, 47, water channel, 48, second gas channel, 49, communication channel.

Claims (5)

A base connected to an exhaust gas introduction port into which exhaust gas is introduced, a catalyst case supported by the base and holding a catalyst carrier, a first cylinder surrounding the catalyst case, and surrounding the first cylinder A heat exchanger comprising a second cylinder and a third cylinder surrounding the second cylinder,
Between the outer peripheral surface of the catalyst case and the inner peripheral surface of the first cylindrical body is a first gas flow path through which exhaust gas that has passed through the catalyst carrier flows toward the base,
Between the outer peripheral surface of the first cylindrical body and the inner peripheral surface of the second cylindrical body is a water channel through which water flows,
Between the outer peripheral surface of the second cylindrical body and the inner peripheral surface of the third cylindrical body, an exhaust gas exhaust port in which exhaust gas that has passed through the first gas flow path is formed at the bottom of the third cylindrical body And a second gas flow path that is discharged to the outside,
The second gas flow path is communicated with the first gas flow path by a communication path provided closer to the base than the end of the water channel ,
The base is a hollow body formed by joining a first member connected to the introduction port and a second member disposed on the downstream side of the first member;
The inner periphery of the base is the communication path,
The second gas flow path and the communication path are communicated via a plurality of communication holes formed in the second member, or the first gas flow path and the communication path are the first Communicated through a plurality of communication holes formed in the cylinder,
The plurality of communication holes are formed such that a flow passage area increases as the distance from the exhaust gas discharge port increases . A base connected to an exhaust gas introduction port into which exhaust gas is introduced, a catalyst case supported by the base and holding a catalyst carrier, a first cylinder surrounding the catalyst case, and surrounding the first cylinder A heat exchanger comprising a second cylinder and a third cylinder surrounding the second cylinder,
Between the outer peripheral surface of the catalyst case and the inner peripheral surface of the first cylindrical body is a first gas flow path through which exhaust gas that has passed through the catalyst carrier flows toward the base,
Between the outer peripheral surface of the first cylindrical body and the inner peripheral surface of the second cylindrical body is a water channel through which water flows,
Between the outer peripheral surface of the second cylindrical body and the inner peripheral surface of the third cylindrical body, an exhaust gas exhaust port in which exhaust gas that has passed through the first gas flow path is formed at the bottom of the third cylindrical body And a second gas flow path that is discharged to the outside,
The second gas flow path is communicated with the first gas flow path by a communication path provided closer to the base than the end of the water channel,
The central axis of the second cylindrical body is away from the water discharge port formed in the second cylindrical body with respect to the central axes of the first cylindrical body and the third cylindrical body arranged concentrically. Placed and
The heat exchanger according to claim 1, wherein the exhaust gas discharge port is arranged with respect to the water discharge port with a central axis of the first cylinder and the third cylinder interposed therebetween . 2. The heat exchanger according to claim 1, wherein the second member is formed integrally with either the end of the first cylinder or the end of the second cylinder. The heat exchanger according to claim 1 or 3, wherein the third cylinder is joined at the same joint as the first member and the second member. It said second member, the heat exchanger according to claim 1, characterized in that it is integrally formed on an end portion of the third tubular member.

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