JP6866772B2 - How to manufacture the exhaust manifold - Google Patents

Description

The present invention relates to a method for manufacturing an exhaust manifold.

Patent Document 1 discloses a conventional exhaust manifold. This exhaust manifold includes a manifold body and a cylinder. The manifold body is made of metal and has a plurality of inlets and one outlet. The tubular body is housed in a manifold and extends in a tubular shape from each inlet to the outlet. The cylinder is a rigid body made of ceramic.

This exhaust manifold is mounted on the engine. As a result, the exhaust gas discharged from the engine flows into each inflow port. Then, this exhaust gas is guided to the outlet by circulating inside the cylinder. In this way, the exhaust gas flows out from the outlet to the outside of the exhaust manifold.

By the way, since the exhaust gas discharged from the engine becomes hot, the exhaust manifold is required to have heat resistance to the heat of the exhaust gas. In this respect, since the exhaust manifold described in Patent Document 1 is made of ceramic, the heat resistance to the heat of the exhaust can be ensured by the cylinder. Therefore, this exhaust manifold exhibits heat resistance to the heat of the exhaust.

Jikkenhei 6-63822

However, in order to reduce the weight of vehicles provided with an exhaust manifold, the exhaust manifold is required to be lighter. In this respect, it is difficult to reduce the weight of the conventional exhaust manifold because the cylinder is a rigid body made of ceramic and the cylinder itself has an appropriate weight.

Further, in this exhaust manifold, the coefficient of thermal expansion differs between the metal manifold body and the ceramic cylinder. Therefore, when the manifold body is thermally deformed, the stress at that time acts on the cylinder. As a result, there is a concern that the cylinder may be damaged in the manifold body.

The present invention has been made in view of the above-mentioned conventional circumstances, and provides an exhaust manifold capable of achieving weight reduction while ensuring heat resistance to exhaust heat and exhibiting high durability. This is an issue that needs to be resolved.

The exhaust manifold of the present invention includes a manifold body formed of metal and having an inflow port into which the exhaust gas discharged from the engine flows in and an outflow port in which the exhaust gas flowing in from the inflow port flows out to the outside.
It is provided with a tubular body housed in the manifold main body, extending in a tubular shape from the inlet to the outlet, and internally guiding the exhaust.
The cylindrical body is characterized by being formed by a fabric material having flexibility and having a heat resistance against heat of the exhaust.

In the exhaust manifold of the present invention, the cloth material forming the cylinder has heat resistance to the heat of the exhaust and also has flexibility. Therefore, the cylinder formed of this cloth material can ensure heat resistance against the heat of the exhaust gas. Here, in this exhaust manifold, since the cylinder body is formed of a cloth material, the weight of the cylinder body can be reduced as compared with the case where the cylinder body is formed of a rigid ceramic body, for example.

Further, since this cylinder has flexibility, even if the manifold body is thermally deformed, the cylinder can be deformed in the manifold body. That is, in this exhaust manifold, if the manifold body is thermally deformed and the stress at that time acts on the cylinder body, the cylinder body bends in the manifold body, and the stress acting on itself can be released. As a result, in this exhaust manifold, even if the manifold body is thermally deformed, the cylinder body is not easily damaged by it.

Therefore, the exhaust manifold of the present invention can realize weight reduction while ensuring heat resistance to the heat of the exhaust, and can exhibit high durability.

In particular, in the exhaust manifold of the present invention, the manifold body is located outside the cylinder because the cylinder is housed inside the manifold body. As a result, even if the exhaust leaks from the cylinder, the exhaust stops between the cylinder and the manifold body, so that the exhaust does not leak to the outside of the exhaust manifold.

It is preferable that a space for separating the manifold body and the cylinder is formed between the manifold body and the cylinder. In this case, due to the heat insulating effect of the air existing in the space, the heat of the exhaust gas circulating in the cylinder is difficult to be transferred to the manifold body. As a result, it becomes difficult for the exhaust gas to be dissipated to the outside through the manifold body, so that it is possible to prevent the exhaust gas circulating in the cylinder from being unnecessarily cooled. Further, by separating the manifold body and the cylinder body by the space, it is possible to suppress the noise when the exhaust gas flows through the cylinder body from leaking to the outside of the manifold body.

Further, it is preferable that the space is filled with whiskers having heat resistance to the heat of the exhaust gas. In this case, the heat of the exhaust gas circulating in the cylinder can be made difficult to be transmitted by the manifold body. Further, the whiskers filled in the space can make it difficult for the noise generated when the exhaust gas flows through the cylinder to leak to the outside of the manifold body.

It is preferable that a separating member for separating the manifold body and the cylinder is provided between the manifold body and the cylinder. In this case, it is possible to preferably form a space between the manifold body and the cylinder.

The exhaust manifold of the present invention can realize weight reduction while ensuring heat resistance to the heat of the exhaust, and can exhibit high durability.

FIG. 1 is a cross-sectional view showing the exhaust manifold of the first embodiment. FIG. 2 is a cross-sectional view showing a state in which the cylinder is housed in the manifold main body with respect to the exhaust manifold of the first embodiment. FIG. 3 is a cross-sectional view showing a cross section taken along the line AA of FIG. 1 with respect to the exhaust manifold of the first embodiment. FIG. 4 is a cross-sectional view showing a cross section of the exhaust manifold of the second embodiment in the same direction as that of the third embodiment. FIG. 5 is a cross-sectional view showing a cross section of the exhaust manifold of the third embodiment in the same direction as that of FIG.

Hereinafter, Examples 1 to 3 embodying the present invention will be described with reference to the drawings.

(Example 1)
As shown in FIG. 1, the exhaust manifold of the first embodiment includes a manifold main body 1 and a tubular body 3. This exhaust manifold is mounted on the engine 100 of the vehicle and is arranged in the engine room ER. In FIG. 1, in order to facilitate the explanation, the engine 100 is shown in a simplified manner and is shown by a virtual line.

In FIG. 1, the front-rear direction and the left-right direction are defined with reference to the posture of the exhaust manifold when it is mounted on the engine 100. Then, in FIGS. 2 and 2, the front-rear direction and the left-right direction are defined corresponding to FIG. The front-rear direction and the left-right direction are examples, and are appropriately changed depending on the posture of the exhaust manifold.

The manifold body 1 shown in FIGS. 1 and 2 is formed by casting cast iron, and has a substantially cylindrical shape in which an outer peripheral surface 1a and an inner peripheral surface 1b are formed. Further, the manifold main body 1 has first to fourth inlets 11a to 11d and outlets 11e. The first to fourth inflow ports 11a to 11d are arranged on the right side of the exhaust manifold 1, that is, on the engine 100 side, respectively, and the first inflow port 11a, the second inflow port 11b, and the third inflow port are arranged from the front to the rear. The inlet 11c and the fourth inlet 11d are arranged in this order. The first to fourth inflow ports 11a to 11d have the same configuration, and are open toward the engine 100 side while being continuous with the inner peripheral surface 1b. Further, on the inner peripheral surface 1b, the first recess 111 is formed in an annular shape on the left side of the first inflow port 11a, and the second recess 112 is formed in an annular shape on the left side of the second inflow port 11b. Similarly, on the inner peripheral surface 1b, the third recess 113 is formed in an annular shape on the left side of the third inflow port 11c, and the fourth recess 114 is formed in an annular shape on the left side of the fourth inflow port 11d. ..

The outlet 11e is located on the left side of the manifold main body 1, that is, on the opposite side of the first to fourth inflow ports 11a to 11d, and is arranged substantially in the center of the manifold main body 1 in the front-rear direction. The outflow port 11e is continuous with the inner peripheral surface 1b and opens toward the opposite side of the first to fourth inflow ports 11a to 11d. The outlet 11e communicates with the first to fourth inlets 11a to 11d, respectively. Further, on the inner peripheral surface 1b, a fifth recess 115 is formed in an annular shape on the right side of the outlet 11e. The shape of the manifold main body 1 can be appropriately designed according to the position where the exhaust manifold is mounted on the engine 100, the position of the muffler 101 connected to the outlet 11e, and the like. Further, the manifold body 1 may be formed of another metal.

As shown in FIG. 1, the tubular body 3 is housed in the manifold main body 1. The tubular body 3 is made of a cloth material having heat resistance to the heat of exhaust gas and having flexibility. In this exhaust manifold, ceramic cloth, which is a public product, is used as the cloth material. This ceramic cloth is smaller than the manifold body 1 and is formed in a shape substantially similar to that of the manifold body 1. As a result, the tubular body 3 is smaller than the manifold main body 1 and has a shape substantially similar to that of the manifold main body 1. More specifically, the tubular body 3 has an outer peripheral surface 3a and an inner peripheral surface 3b formed therein, and extends in a tubular shape from the first to fourth inflow ports 11a to 11d of the manifold main body 1 to the outflow port 11e. Further, the tubular body 3 has first to fourth inflow guide portions 31a to 31d and outflow guide portions 31e which are continuous with the inner peripheral surface 3b, respectively. The first to fourth inflow guide portions 31a to 31d are located on the right end side of the tubular body 3, and are arranged in the first to fourth inflow ports 11a to 11d, respectively. The first to fourth inflow guide portions 31a to 31d have the same configuration, and are open toward the engine 100 side as in the first to fourth inflow inlets 11a to 11d. The outflow guide portion 31e is located on the left end side of the tubular body 3 and is arranged in the outflow port 11e. The outflow guide portion 31e opens in the same direction as the outflow port 11e, that is, toward the opposite side of the first to fourth inflow guide portions 31a to 31d. The outflow guide units 31e communicate with the first to fourth inflow guide units 31a to 31d, respectively. In FIG. 1, the thicknesses of the manifold body 1 and the cylinder 3 are exaggerated for the sake of simplicity. The same applies to FIGS. 2 to 5.

Further, as shown in FIG. 1, first to fourth circlips 5a to 5d are provided in the first to fourth inflow guide portions 31a to 31d, respectively. Further, a fifth circlip 5e is provided in the outflow guide portion 31e. The first to fifth circlips 5a to 5e are fitted in the first to fifth recesses 111 to 115, respectively. Details of these 1st to 5th circlips 5a to 5e will be described later.

A plurality of spacers 7 are provided on the outer peripheral surface 3a of the tubular body 3. Each spacer 7 is an example of a "separation member" in the present invention. Each spacer 7 is formed by bundling ceramic threads into a spherical shape. Each spacer 7 is attached to the outer peripheral surface 3a by being sewn to the outer peripheral surface 3a. The shape, number, and material of each spacer 7 can be appropriately designed.

Further, as shown in FIGS. 1 and 3, in this exhaust manifold, the inner peripheral surface 1b of the manifold body 1 and the outer peripheral surface 3a of the cylinder 3 are in a state where the cylinder 3 is housed in the manifold body 1. A space 9 is formed between them. Air exists in the space 9. As a result, at the location where the space 9 is formed in the manifold body 1, the cylinder 3 is separated from the manifold body 1, and the inner peripheral surface 1b of the manifold body 1 and the outer peripheral surface 3a of the cylinder 3 are not in contact with each other. It has become. That is, at the place where the space 9 is formed, an air layer exists between the manifold main body 1 and the tubular body 3.

This exhaust manifold is manufactured as follows. First, as shown in FIG. 2, the above-mentioned manifold main body 1 is prepared, and the first to fourth traction members 13a to 13d are prepared. The first traction member 13a includes a string-shaped first main body portion 131a and a first holding member 131b fixed to one end side of the first main body portion 131a. The second to fourth traction members 13b to 13d have the same configuration as the first traction member 13a, and are fixed to each one end side of the second to fourth main body portions 132a to 134a and the second to fourth main body portions 132a to 134a, respectively. It is composed of the second to fourth holding members 132b to 134b.

Next, the first holding member 131b is positioned outside the outlet 11e by passing the first traction member 13a from the first inlet 11a of the manifold body 1 to the outlet 11e. Similarly, the second holding member 132b is positioned outside the outflow port 11e by passing the second traction member 13b from the second inflow port 11b to the outflow port 11e. Further, the third holding member 133b is positioned outside the outflow port 11e by passing the third traction member 13c from the third inflow port 11c to the outflow port 11e. Further, the fourth holding member 134b is positioned outside the outlet 11e by passing the fourth traction member 13d from the fourth inlet 11d to the outlet 11e.

Then, by causing the first to fourth inflow guide portions 31a to 31d of the cylinder body 3 to hold the first to fourth holding members 131b to 134b, respectively, the cylinder body 3 and the first to fourth traction members 13a are held outside the manifold main body 1. ~ 13d are connected.

Next, in FIG. 1, the tubular body 3 is shown in FIG. 1 so that the tubular body 3 can pass through the outlet 11e by utilizing the flexible property of the cloth material constituting the tubular body 3, that is, the ceramic cloth. By putting them together smaller than the initial state shown, the contracted state shown in FIG. 2 is obtained. In this state, as shown by the white arrows in the figure, the first to fourth main bodies 131a to 134a are pulled to the right side of the manifold main body 1 from the outside of the first to fourth inflow ports 11a to 11d, respectively. As a result, the tubular body 3 enters the manifold main body 1 from the outlet 11e side. Then, by further pulling the first to fourth main bodies 131a to 134a to the right side of the manifold main body 1, the first inflow guide portion 31a is guided to the first inflow port 11a by the first pulling member 13a. Similarly, the second inflow guide portion 31b is guided to the second inflow port 11b by the second traction member 13b, and the third inflow guide portion 31c is guided to the third inflow port 11c by the third traction member 13c. Further, the fourth inflow guide portion 31d is guided to the fourth inflow port 11d by the fourth traction member 13d.

In this way, the first to fourth inflow guides 31a to 31d are guided to the first to fourth inflow ports 11a to 11d, respectively, so that the outflow guides 31e are located in the outflow port 11e. In this way, the tubular body 3 is housed in the manifold main body 1.

Next, the first to fourth circlips 5a to 5d are inserted into the first to fourth inflow guide portions 31a to 31d while being elastically deformed from the basic shape in the product state. As a result, these first to fourth circlips 5a to 5d are restored to their basic shapes at the positions where the first to fourth recesses 111 to 114 are present. At this time, as shown in FIG. 1, the first circlip 5a is fitted into the first recess 111 with a part of the first inflow guide portion 31a sandwiched in the first recess 111. Similarly, the 2nd to 4th circlips 5b to 5d also have the 2nd to 4th recesses 112 to 112 in a state where a part of the 2nd to 4th inflow guide portions 31b to 31d is sandwiched in the 2nd to 4th recesses 112 to 114 respectively. It is fitted in 114. Further, the fifth circlip 5e is inserted into the outflow guide portion 31e while being elastically deformed from the basic shape. Similarly, the fifth circlip 5e is also restored to the basic shape at the position where the fifth recess 115 exists, so that the fifth recess is sandwiched in the fifth recess 115 with a part of the outflow guide portion 31e. It is fitted in 115. As a result, the 1st to 5th circlips 5a to 5e function as fixing members, and the 1st to 4th inflow guides 31a to 31d are fixed in the 1st to 4th inflow ports 11a to 11d, respectively, and the outflow guides are fixed. 31e is fixed in the outlet 11e. In this way, the tubular body 3 is prevented from coming off from the manifold main body 1. In this state, the first to fourth holding members 131a to 134a are removed from the first to fourth inflow guide portions 31a to 31d, respectively, and the connection between the tubular body 3 and the first to fourth traction members 13a to 13d is released. After the connection between the tubular body 3 and the first to fourth traction members 13a to 13d is released, the tubular body 3 may be prevented from coming off from the manifold main body 1 by the first to fifth circlips 5a to 5e. .. Further, the first to fourth inflow guide portions 31a to 31d are fixed in the first to fourth inflow ports 11a to 11d by members other than the first to fifth circlips 5a to 5e, and the outflow guide portions 31e are fixed to the outflow port. It may be fixed within 11e.

Next, by attaching the manifold main body 1 to an air supply device (not shown), compressed air is supplied from the air supply device to the first to fourth inflow ports 11a to 11d. This compressed air is guided to the outflow port 11e from the first to fourth inflow ports 11a to 11d by flowing through the cylinder 3, and flows out from the outflow port 11e to the outside of the manifold main body 1. In this way, the compressed air circulates in the cylinder 3 to expand the cylinder 3, so that the cylinder 3 is restored from the contracted state to the initial state. As a result, as shown in FIGS. 1 and 3, each spacer 7 comes into contact with the inner peripheral surface 1b of the manifold main body 1. Therefore, a space 9 is formed between the inner peripheral surface 1b and the outer peripheral surface 3a of the tubular body 3. After that, the exhaust manifold is completed by removing the manifold main body 1 from the air supply device.

The exhaust manifold thus manufactured is mounted on the engine 100 and is arranged in the engine room ER of the vehicle. Further, the first to fourth inflow ports 11a to 11d communicate with the exhaust port (not shown) of the engine 100. Further, in the exhaust manifold, the outlet 11e is connected to the muffler 101. These engines 100 and muffler 101 are public products, and detailed description of the configuration will be omitted. Further, in FIG. 1, for ease of explanation, the muffler 101 is also illustrated by a virtual line. The outlet 11e may be connected to the supercharger.

Then, in the exhaust manifold, when the engine 100 is operated, the exhaust gas discharged from the engine 100 flows into the first to fourth inflow ports 11a to 11d, respectively, as shown by the broken line arrow in FIG. The exhaust gas that has flowed into the first to fourth inflow ports 11a to 11d is guided to the outflow port 11e by the tubular body 3 by circulating from the inside of the first to fourth inflow guide portions 31a to 31d to the inside of the outflow guide portion 31e. .. Then, the exhaust gas reaching the outlet 11e is circulated from the outlet 11e to the muffler 101 outside the exhaust manifold, and is discharged to the outside of the vehicle through the muffler 101.

In this exhaust manifold, the ceramic cloth forming the cylinder 3 has heat resistance to the heat of the exhaust and is flexible. Therefore, the cylinder 3 is ensured to have heat resistance to the heat of the exhaust gas. In particular, since the exhaust manifold uses a ceramic cloth, it is possible to secure the same heat resistance in the cylinder 3 as in the case of a rigid ceramic body. Further, in this exhaust manifold, a space 9 is formed between the inner peripheral surface 1b of the manifold body 1 and the outer peripheral surface 3a of the cylinder 3 in a state where the cylinder 3 is housed in the manifold body 1. At the place where the space 9 exists, the manifold main body 1 and the tubular body 3 are separated from each other. As a result, due to the heat insulating effect of the air existing in the space 9, the heat of the exhaust gas circulating in the cylinder 3 is difficult to be transferred to the manifold main body 1.

Further, in this exhaust manifold, since the cylinder body 3 is formed of a ceramic cloth, it is possible to reduce the weight of the cylinder body 3 as compared with the case where the cylinder body 3 is formed of a rigid ceramic body, for example. ..

Further, since the tubular body 3 has flexibility, even if the manifold main body 1 is thermally deformed, the tubular body 3 can be deformed in the manifold main body 1. That is, in this exhaust manifold, if the manifold body 1 is thermally deformed and the stress at that time acts on the cylinder 3, the cylinder 3 bends in the manifold body 1 to release the stress acting on itself. it can. As a result, in this exhaust manifold, even if the manifold body 1 is thermally deformed, the cylinder 3 is less likely to be damaged.

Therefore, the exhaust manifold of the first embodiment can realize weight reduction while ensuring heat resistance to the heat of the exhaust, and can exhibit high durability.

In particular, in this exhaust manifold, the manifold body 1 is located outside the cylinder 3 because the cylinder 3 is housed in the manifold body 1. As a result, even if the exhaust gas leaks from the cylinder body 3, the exhaust gas stops between the cylinder body 3 and the manifold body 1, that is, in the space 9, and therefore leaks into the engine room ER outside the exhaust manifold. Never.

Further, since air exists in the space 9 of this exhaust manifold, it is difficult for the exhaust flowing in the cylinder 3 to be dissipated into the engine room ER through the manifold main body 1 due to the heat insulating effect of the air. Therefore, in this exhaust manifold, it is possible to prevent the exhaust gas circulating in the cylinder 3 from being unnecessarily cooled. As a result, when the outlet 11e is connected to the muffler 101 as described above, the catalyst (not shown) provided in the muffler 101 is heated to the required temperature at an early stage by the heat of the exhaust gas. Is possible. Further, when the outlet 11e is connected to the supercharger, the supercharger can be operated suitably, so that the output of the engine 100 can be improved more preferably.

Further, by forming the space 9, the exhaust manifold can suppress the noise when the exhaust flows through the cylinder 3 from the manifold main body 1 into the engine room ER. Therefore, this exhaust manifold is also excellent in quietness.

Further, in this exhaust manifold, since a plurality of spacers 7 are provided between the inner peripheral surface 1b of the manifold main body 1 and the outer peripheral surface 3a of the tubular body 3, each of these spacers 7 provides the inner peripheral surface 1 of the manifold main body 1. It is possible to preferably form a space 9 between the peripheral surface 1b and the outer peripheral surface 3a of the tubular body 3. Further, since each spacer 7 is formed of a ceramic thread, each spacer 7 itself is also lightweight. Further, in this exhaust manifold, the heat of the exhaust flowing in the cylinder 3 is difficult to be transferred to the manifold main body 1 through each spacer 7.

(Example 2)
The exhaust manifold of the second embodiment includes the cylinder 4 shown in FIG. 4 instead of the cylinder 3 of the exhaust manifold of the first embodiment. The cylinder 4 is composed of a first cylinder 41 and a second cylinder 43 provided in the first cylinder 41, and has a double structure of the first cylinder 41 and the second cylinder 43. It has become. Further, in this exhaust manifold, a whisker 15 is provided between the manifold body 1 and the cylinder 4. The whiskers 15 have heat resistance to the heat of exhaust gas.

Similar to the above-mentioned cylinder 3, the first cylinder 41 and the second cylinder 43 constituting the cylinder 4 are also made of ceramic cloth. As a result, the first cylinder 41 and the second cylinder 43 also have heat resistance and flexibility. The first tubular body 41 has a substantially cylindrical shape in which an outer peripheral surface 41a and an inner peripheral surface 41b are formed. Each configuration including the shape of the first tubular body 41 is the same as that of the tubular body 3. Further, similarly to the tubular body 3, a plurality of spacers 7 are attached to the outer peripheral surface 41a of the first tubular body 41.

The second tubular body 43 has a substantially cylindrical shape in which an outer peripheral surface 43a and an inner peripheral surface 43b are formed. The second tubular body 43 is smaller than the first tubular body 41 and is formed in a shape similar to that of the first tubular body 41. As a result, each configuration of the second tubular body 43 is the same as that of the first tubular body 41. Further, a plurality of spacers 17 are attached to the outer peripheral surface 43a of the second tubular body 43. Each spacer 17 is also formed by bundling ceramic threads in a spherical shape, and is sewn to the outer peripheral surface 43a. Further, each spacer 17 is formed to be smaller than each spacer 7. The shape, number, and material of each spacer 17 can be appropriately designed. Further, each spacer 7 and each spacer 17 may be formed of different materials.

Although detailed illustration is omitted, in forming the exhaust manifold, the tubular body 4 contracts from the initial state in the same manner as the tubular body 3 in a state where the second tubular body 43 is provided in the first tubular body 41. It is considered to be in a state. Then, the tubular body 4 is housed in the manifold main body 1 in the same manner as the exhaust manifold of the first embodiment. At this time, the whisker 15 is filled between the manifold body 1 and the cylinder 4. Then, in the cylinder 4, the second cylinder 43 is restored to the initial state by circulating compressed air in the second cylinder 43, and each spacer 17 comes into contact with the inner peripheral surface 41b of the first cylinder 41. .. As a result, the in-cylinder space 19 is formed between the inner peripheral surface 41b of the first tubular body 41 and the outer peripheral surface 43a of the second tubular body 43. Further, in the tubular body 4, compressed air is also circulated in the in-cylinder space 19. As a result, the first tubular body 41 is also restored to the initial state, and each spacer 7 comes into contact with the inner peripheral surface 1b of the manifold body 1. In this way, similarly to the above-mentioned tubular body 3, the space 9 is between the manifold main body 1 and the tubular body 4, and more specifically, between the inner peripheral surface 1b of the manifold main body 1 and the outer peripheral surface 41a of the first tubular body 41. Is formed.

Here, in this exhaust manifold, since the whiskers 15 are provided between the manifold main body 1 and the tubular body 4, the space 9 is filled with not only air but also whiskers 15. Then, similarly to the tubular body 3, the tubular body 4 is also prevented from coming off from the manifold main body 1 by the first to fifth circlips 5a to 5e. In this way, the exhaust manifold is completed. The other configurations of the exhaust manifold are the same as those of the exhaust manifold of the first embodiment, and the same configurations are designated by the same reference numerals and detailed description of the configurations will be omitted.

In this exhaust manifold, the exhaust gas that has flowed into the first to fourth inflow ports 11a to 11d is guided to the outflow port 11e by the cylinder body 4. At this time, the exhaust gas circulates in the second cylinder 43. Here, since the in-cylinder space 19 exists between the second cylinder 43 and the first cylinder 41, the first cylinder 41 and the second cylinder 43 are separated from each other, and the second cylinder 43 is separated. It is difficult for the heat of the exhaust gas circulating inside to be transferred to the first cylinder 41. As described above, in this exhaust manifold, the cylinder body 4 has a double structure of the first cylinder body 41 and the second cylinder body 43, so that higher heat resistance to the heat of the exhaust can be exhibited. It is possible. Further, since the tubular body 4 has a double structure of the first tubular body 41 and the second tubular body 43, it is more difficult for the exhaust gas to leak from the tubular body 4. Here, since both the first cylinder 41 and the second cylinder 43 are made of ceramic cloth, the weight of the cylinder 4 can be reduced even with such a double structure.

Further, in this exhaust manifold, the whiskers 15 filled in the space 9 exert a heat insulating effect. Therefore, as compared with the exhaust manifold of the first embodiment, in this exhaust manifold, the heat of the exhaust gas circulating in the cylinder 4 is less likely to be transmitted by the manifold main body 1. Therefore, in this exhaust manifold, the exhaust gas circulating in the cylinder 4 is less likely to be dissipated by the engine room ER through the manifold body 1, and the exhaust gas circulating in the cylinder 4 is less likely to be cooled. Further, since the whisker 15 has heat resistance to the heat of the exhaust gas, the whisker 15 is less likely to be deteriorated by the heat of the exhaust gas circulating in the cylinder 4.

Further, since the whisker 15 is filled in the space 9, the noise generated when the exhaust gas flows through the cylinder 4 is less likely to leak into the engine room ER. Therefore, this exhaust manifold can exhibit higher quietness than the exhaust manifold of the first embodiment. Other actions in this exhaust manifold are similar to those of the exhaust manifold of Example 1.

(Example 3)
As shown in FIG. 5, in the exhaust manifold of the third embodiment, unlike the exhaust manifold of the first embodiment, a plurality of convex portions 1c are integrally formed on the inner peripheral surface 1b of the manifold main body 1. Each convex portion 1c projects substantially hemispherically from the inner peripheral surface 1b toward the tubular body 3 side. Each convex portion 1c is also an example of the "separation member" in the present invention. The shape and number of each convex portion 1c can be appropriately designed.

Further, in this exhaust manifold, the spacer 7 is not attached to the outer peripheral surface 3a of the tubular body 3. Then, in this exhaust manifold, each convex portion 1c comes into contact with the outer peripheral surface 3a of the tubular body 3, so that the manifold main body 1 and the tubular body 3 are separated from each other. In this way, even in this exhaust manifold, a space 9 is formed between the inner peripheral surface 1b of the manifold main body 1 and the outer peripheral surface 3a of the tubular body 3. As with the exhaust manifold of the first embodiment, by attaching the spacer 7 to the outer peripheral surface 3a of the tubular body 3, the manifold main body 1 and the tubular body 3 are separated by each convex portion 1c and each spacer 7 to create a space 9. It may be formed. Other configurations of this exhaust manifold are the same as those of the exhaust manifold of the first embodiment.

In this exhaust manifold, each convex portion 1c can be formed at the same time when the manifold body 1 is cast. Therefore, as compared with the case where each spacer 7 is attached to the outer peripheral surface 3a of the tubular body 3, the exhaust manifold can be manufactured more easily. Other actions in this exhaust manifold are similar to those of the exhaust manifold of Example 1.

In the above, the present invention has been described with reference to Examples 1 to 3, but the present invention is not limited to the above Examples 1 to 3, and can be appropriately modified and applied without departing from the spirit thereof. Needless to say.

For example, the exhaust manifold may be formed by appropriately combining the configurations of the exhaust manifolds of Examples 1 to 3.

Further, in the exhaust manifold of Example 1, the cylinder body 3 is formed of a ceramic cloth, but the present invention is not limited to this, and any cloth material having heat resistance and flexibility against the heat of the exhaust is a cloth other than the ceramic cloth. The tubular body 3 may be formed of the material. The same applies to the exhaust manifolds of Examples 2 and 3.

Further, in the exhaust manifold of the first embodiment, the manifold main body 1 has the first to fourth inflow ports 11a to 11d. However, the present invention is not limited to this, and depending on the configuration of the engine 100, the manifold main body 1 may have only the first inflow port 11a, and the inflow port may be provided in addition to the first to fourth inflow ports 11a to 11d. You may have. At this time, the tubular body 3 is provided with an inflow guide portion according to the number of inflow ports of the manifold main body 1. The same applies to the exhaust manifolds of Examples 2 and 3.

Further, in the exhaust manifold of the first embodiment, the compressed air is circulated in the cylinder 3 to restore the contracted cylinder 3 to the initial state. However, the present invention is not limited to this, and the contracted cylinder 3 may be restored to the initial state by circulating the exhaust gas discharged from the engine 100 into the cylinder 3. The same applies to the exhaust manifolds of Examples 2 and 3.

Further, in the exhaust manifold of the first embodiment, the tubular body 3 extends in a tubular shape from the first to fourth inflow ports 11a to 11d of the manifold main body 1 to the outflow port 11e. However, the present invention is not limited to this, and the tubular body 3 may extend in a tubular shape between the first to fourth inflow ports 11a to 11d of the manifold main body 1 and the outflow port 11e. Therefore, with respect to the exhaust manifold of the first embodiment, the tubular body 3 is provided only in the places between the first to fourth inflow ports 11a to 11d to the outflow port 11e where heat resistance to the heat of the exhaust is particularly required. It may be configured. The same applies to the exhaust manifolds of Examples 2 and 3.

Further, in the exhaust manifold of the second embodiment, the tubular body 4 is not limited to the double structure, but may have a triple structure or a quadruple structure. Further, between the first to fourth inflow ports 11a to 11d to the outflow port 11e, the tubular body 4 has a double structure, a triple structure, or a quadruple structure only in a place where heat resistance to the heat of the exhaust is particularly required. It may be a structure. Further, the tubular body 4 may be configured without forming the in-cylinder space 19.

Further, in the exhaust manifold of the second embodiment, the whisker 15 does not necessarily have to be filled in the entire space 9, and is heat resistant to the heat of the exhaust between the first to fourth inlets 11a to 11d to the outlet 11e. The whisker 15 may be filled in the space 9 only in a place where the property is particularly required.

The present invention can be used for pipes and the like for circulating high-temperature fluids.

1 ... Manifold body 1c ... Convex part (separation member)
3 ... Cylinder 7 ... Spacer (separation member)
9 ... Space 11a-11d ... 1st to 4th inlets (inflows)
11e ... Outlet 15 ... Whisker 100 ... Engine

Claims (1)

A manifold body formed of metal and having an inflow port into which the exhaust gas discharged from the engine flows in, and an outflow port in which the exhaust gas flowing in from the inflow port flows out to the outside.
It is made of a cloth material that has heat resistance to the heat of the exhaust and is flexible, is housed in the manifold body, extends in a tubular shape from the inlet to the outlet, and internally exhausts the exhaust. It is a method of manufacturing an exhaust manifold equipped with a guiding cylinder.
The manifold body and the string-shaped traction member are prepared, and the traction member is inserted into the manifold body so that one end of the traction member is located outside the outlet, while the traction member and others. The process of locating the end outside the inlet and
A step of bending the cylinder outside the manifold body to bring the cylinder into a contracted state smaller than the initial state.
A step of connecting one end of the traction member to the contracted cylinder outside the outlet.
By pulling the other end of the traction member from the outside of the inflow port, the tubular body in the contracted state is made to enter the manifold main body from the outflow port, and the tubular body is introduced into the manifold main body. The process of accommodating and
A method for manufacturing an exhaust manifold, which comprises a step of restoring the tubular body housed in the manifold main body from the contracted state to the initial state.

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