Exhaust emission control device

Abstract

To firmly fix an exhaust emission control device to inside of an exhaust pipe.SOLUTION: An exhaust emission control device includes a body. The body includes a reactor part and a first support part. The reactor part extends in a right / left direction and includes spaces through which exhaust gas passes in a forward / backward direction. PMs included in exhaust gas are removed by plasma when passing through the spaces. The first support part extends in the forward / backward direction and is connected to a left end of the reactor part. Length in the forward / backward direction of the first support part is longer than that in the forward / backward direction of the reactor part.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an exhaust gas purification device.

Background Art

[0002] As an invention related to a conventional exhaust gas purification device, for example, a plasma reactor described in Patent Document 1 is known. This plasma reactor has a structure in which a plurality of dielectrics and a plurality of electrodes are laminated. Such a plasma reactor is disposed in an exhaust pipe.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, there is a desire to firmly fix the plasma reactor described in Patent Document 1 in a pipe.

[0005] Therefore, an object of the present invention is to firmly fix an exhaust gas purification device in an exhaust pipe.

Means for Solving the Problems

[0006] A first aspect is that the exhaust gas purification device includes a main body, the main body includes a reactor part and a first support part, the reactor part extends in the left-right direction, and a space through which exhaust gas passes in the front-rear direction is provided, PM contained in the exhaust gas is removed by plasma when passing through the space, the first support part extends in the front-rear direction and is connected to the left end of the reactor part, The length of the first support portion in the front-rear direction is longer than the length of the reactor portion in the front-rear direction. It is an exhaust gas purification device.

[0007] The second side surface is The main body further includes a second support portion. The second support portion extends in the front-rear direction and is connected to the right end of the reactor portion. The length of the second support portion in the front-rear direction is longer than the length of the reactor portion in the front-rear direction. It is the exhaust gas purification device described in the first side surface.

[0008] The third side surface is The exhaust gas purification device is disposed in the exhaust pipe. The exhaust gas purification device further includes a first holding member and a second holding member. The first holding member is in contact with the upper surface of the first support portion and the upper surface of the exhaust pipe. The second holding member is in contact with the lower surface of the first support portion and the lower surface of the exhaust pipe. It is the exhaust gas purification device described in the first side surface or the second side surface.

[0009] The fourth side surface is The first holding member is in contact with the upper surface of the reactor portion. The second holding member is in contact with the lower surface of the reactor portion. It is the exhaust gas purification device described in the third side surface.

Advantages of the Invention

[0010] According to the present invention, the exhaust gas purification device can be firmly fixed in the exhaust pipe.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

MODE FOR CARRYING OUT THE INVENTION

[0012] (Embodiment) [Structure of Exhaust Gas Purification Device 10] The structure of the exhaust gas purification device 10 according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of the exhaust gas purification device 10. FIG. 2 is an exploded perspective view of the main body 12. FIG. 3 is a perspective view of the main body 12 of the exhaust gas purification device 10. FIG. 4 is a perspective view of the exhaust gas purification device 10 and the exhaust pipe 100.

[0013] In this specification, the direction in which the ceramic layers 36-1 to 36-n, 38-1 to 38-n, and 40-1 to 40-n-1 shown in FIG. 3 are laminated is defined as the vertical direction. Also, the direction in which the exhaust gas flows is defined as the rear direction. The vertical direction, the left-right direction, and the front-rear direction are orthogonal to each other. Note that the vertical direction, the left-right direction, and the front-rear direction in this specification are examples and do not have to coincide with the vertical direction, the left-right direction, and the front-rear direction of the vehicle.

[0014] The exhaust gas purification device 10 removes PM (Particulate Matter) from the exhaust gas discharged from the internal combustion engine of the vehicle. As shown in FIG. 1, the exhaust gas purification device 10 includes a main body 12, a first holding member 14, a second holding member 16, a third holding member 18, and a fourth holding member 20.

[0015] As shown in FIG. 2, the main body 12 includes a reactor section 30, a first support section 32, and a second support section 34. The main body 12 has an H shape when viewed from below. The reactor section 30 extends in the left-right direction. The reactor section 30 has a rectangular parallelepiped shape and has an upper surface, a lower surface, a left surface, a right surface, a front surface, and a rear surface. Each of the upper surface, lower surface, left surface, right surface, front surface, and rear surface of the reactor section 30 is rectangular.

[0016] In the reactor section 30, a plurality of spaces 50-1 to 50-n, 51-1 to 51-n, 52-1 to 52-n, 53-1 to 53-n through which exhaust passes rearward are provided. n is a natural number. The plurality of spaces 50-1 to 50-n, 51-1 to 51-n, 52-1 to 52-n, 53-1 to 53-n extend in the front-rear direction so as to connect the front surface and the rear surface of the reactor section 30. The plurality of spaces 50-1 to 50-n, the plurality of spaces 51-1 to 51-n, the plurality of spaces 52-1 to 52-n, and the plurality of spaces 53-1 to 53-n are arranged in this order from left to right. Also, the spaces 50-1 to 50-n are arranged in this order from top to bottom. The spaces 51-1 to 51-n are arranged in this order from top to bottom. The spaces 52-1 to 52-n are arranged in this order from top to bottom. The spaces 53-1 to 53-n are arranged in this order from top to bottom.

[0017] The first support section 32 extends in the front-rear direction. The first support section 32 has a rectangular parallelepiped shape and has an upper surface, a lower surface, a left surface, a right surface, a front surface, and a rear surface. Each of the upper surface, lower surface, left surface, right surface, front surface, and rear surface of the first support section 32 is rectangular. The first support section 32 is connected to the left end of the reactor section 30. In the present embodiment, the central portion in the front-rear direction of the right surface of the first support section 32 is joined to the left surface of the reactor section 30. Therefore, the first support section 32 protrudes forward and backward from the reactor section 30. The length L2 in the front-rear direction of the first support section 32 is longer than the length L1 in the front-rear direction of the reactor section 30.

[0018] The second support portion 34 extends in the front-rear direction. The second support portion 34 has a rectangular parallelepiped shape and has an upper surface, a lower surface, a left surface, a right surface, a front surface, and a rear surface. Each of the upper surface, the lower surface, the left surface, the right surface, the front surface, and the rear surface of the second support portion 34 is rectangular. The second support portion 34 is connected to the right end of the reactor portion 30. In the present embodiment, the central portion in the front-rear direction of the left surface of the second support portion 34 is joined to the right surface of the reactor portion 30. Therefore, the second support portion 34 protrudes forward and backward from the reactor portion 30. The length L3 of the second support portion 34 in the front-rear direction is longer than the length L1 of the reactor portion 30 in the front-rear direction.

[0019] As shown in FIG. 3, the main body 12 is a laminate. The main body 12 includes ceramic layers 36-1 to 36-n, 38-1 to 38-n, 40-1 to 40-n-1 and electrode layers 42-1 to 42-n, 44-1 to 44-n, 46-1 to 46-n, 48-1 to 48-n. The ceramic layers 36-1, 38-1, 40-1, 36-2, 38-2, 40-2 ··· 36-n, 38-n are laminated in this order from top to bottom.

[0020] The ceramic layers 36-1 to 36-n, 38-1 to 38-n, 40-1 to 40-n-1 have an H shape when viewed downward, similar to the main body 12. However, spaces 50-1, 51-1, 52-1, 53-1 are provided in the ceramic layer 40-1. The spaces 50-1, 51-1, 52-1, 53-1 are arranged at intervals in this order from left to right. The ceramic layers 40-2 to 40-n-1 also have the same structure as the ceramic layer 40-1.

[0021] The materials of the ceramic layers 36-1 to 36-n, 38-1 to 38-n, 40-1 to 40-n-1 as described above are dielectric materials. The dielectric materials are, for example, ceramics such as alumina, zirconia, and aluminum nitride.

[0022] The electrode layers 42-1 to 42-n, 44-1 to 44-n, 46-1 to 46-n, and 48-1 to 48-n have a rectangular shape when viewed from below. The electrode layers 42-1 to 42-n, 44-1 to 44-n, 46-1 to 46-n, and 48-1 to 48-n are provided inside the reactor section 30. Specifically, the electrode layers 42-1, 44-1, 46-1, and 48-1 are provided on the upper main surface of the ceramic layer 36-1. The electrode layers 42-1, 44-1, 46-1, and 48-1 are arranged in this order at intervals from left to right. The electrode layers 42-1, 44-1, 46-1, and 48-1 do not overlap with the spaces 50-1, 51-1, 52-1, and 53-1 when viewed from below. Note that the electrode layers 42-2 to 42-n, 44-2 to 44-n, 46-2 to 46-n, and 48-2 to 48-n have the same structure as the electrode layers 42-1, 44-1, 46-1, and 48-1. As a result, spaces 50-m, 51-m, 52-m, and 53-m are respectively located between two adjacent electrode layers 42-m, 44-m, 46-m, 48-m and electrode layers 42-m+1, 44-m+1, 46-m+1, 48-m+1 in the vertical direction. m is an integer from 0 to n-1.

[0023] The materials of the electrode layers 42-1 to 42-n, 44-1 to 44-n, 46-1 to 46-n, and 48-1 to 48-n as described above are metals. The metals are, for example, tungsten and platinum.

[0024] As shown in FIG. 1, the first holding member 14 is provided on the main body 12. The first holding member 14 has the same H-shaped configuration as the main body 12 when viewed from below. The first holding member 14 is in contact with the upper surface of the reactor section 30, the upper surface of the first support section 32, and the upper surface of the second support section 34. Therefore, the first holding member 14 covers the entire upper surface of the main body 12.

[0025] The second holding member 16 is provided below the main body 12. The second holding member 16 has the same H-shaped configuration as the main body 12 when viewed from below. The second holding member 16 is in contact with the lower surface of the reactor section 30, the lower surface of the first support section 32, and the lower surface of the second support section 34. Therefore, the second holding member 16 covers the entire lower surface of the main body 12.

[0026] The third holding member 18 is provided on the left of the main body 12. The third holding member 18 is in contact with the left surface of the first support portion 32. The fourth holding member 20 is provided on the right of the main body 12. The fourth holding member 20 is in contact with the right surface of the second support portion 34. As described above, the first holding member 14, the second holding member 16, the third holding member 18, and the fourth holding member 20 surround the main body 12 when viewed in the forward direction. However, chamfers are provided at the corners of the first holding member 14, the second holding member 16, the third holding member 18, and the fourth holding member 20 when viewed in the forward direction.

[0027] However, the front and rear surfaces of the main body 12 are not covered by the first holding member 14, the second holding member 16, the third holding member 18, and the fourth holding member 20.

[0028] The first holding member 14, the second holding member 16, the third holding member 18, and the fourth holding member 20 have a structure in which ceramic fibers are hardened. Therefore, the first holding member 14, the second holding member 16, the third holding member 18, and the fourth holding member 20 are softer than the main body 12. Thereby, the first holding member 14, the second holding member 16, the third holding member 18, and the fourth holding member 20 function as protective members for protecting the main body 12.

[0029] The exhaust gas purification device 10 as described above is disposed in the exhaust pipe 100 as shown in FIG. 4. The exhaust pipe 100 has a rectangular shape when viewed in the forward direction. Therefore, the inner peripheral surface of the exhaust pipe 100 has an upper surface, a lower surface, a left surface, and a right surface. The upper surface faces downward. The lower surface faces upward. The left surface faces rightward. The right surface faces leftward. Also, chamfers are provided at the corners of the exhaust pipe 100.

[0030] The first holding member 14 is in contact with the upper surface of the exhaust pipe 100. The second holding member 16 is in contact with the lower surface of the exhaust pipe 100. The third holding member 18 is in contact with the left surface of the exhaust pipe 100. The fourth holding member 20 is in contact with the right surface of the exhaust pipe 100. Also, the chamfered corner in the exhaust purification device 10 is in contact with the chamfered corner in the exhaust pipe 100.

[0031] Next, the operation of the exhaust purification device 10 will be described. An alternating voltage is applied to the electrode layers 42-1 to 42-n, 44-1 to 44-n, 46-1 to 46-n, 48-1 to 48-n. However, different polarities of high voltage are applied to the vertically adjacent electrode layers 42-m, 44-m, 46-m, 48-m and the electrode layers 42-m+1, 44-m+1, 46-m+1, 48-m+1. Thereby, plasma is generated between the vertically adjacent electrode layers 42-m, 44-m, 46-m, 48-m and the electrode layers 42-m+1, 44-m+1, 46-m+1, 48-m+1. Therefore, the PM contained in the exhaust is removed by the plasma when passing through the spaces 50-1 to 50-n, 51-1 to 51-n, 52-1 to 52-n, 53-1 to 53-n.

[0032] [Effect] According to the exhaust purification device 10, the exhaust purification device 10 can be firmly fixed in the exhaust pipe 100. FIG. 5 is a perspective view of the exhaust purification device 210 and the exhaust pipe 100 according to the comparative example.

[0033] The exhaust purification device 210 includes a main body 212, a first holding member 214, and a second holding member 216. The main body 212 has a plate shape having a front main surface and a rear main surface. The first holding member 214 and the second holding member 216 have a rectangular annular shape when viewed in the forward direction. The first holding member 214 is in contact with the front main surface of the main body 212. The second holding member 216 is in contact with the rear main surface of the main body 212.

[0034] The exhaust gas purification device 210 as described above is press-fitted into the exhaust pipe 100. The upper surface, lower surface, left surface, and right surface of the exhaust gas purification device 210 are in contact with the inner peripheral surface of the exhaust pipe 100. And it is fixed to the exhaust pipe 100 by metal fittings 110a and 110b provided in the exhaust pipe 100. Specifically, the metal fittings 110a and 110b have an L shape. The metal fittings 110a and 110b are fixed to the left surface and right surface of the exhaust pipe 100 by welding. The metal fittings 110a and 110b regulate the movement of the exhaust gas purification device 210 in the front-rear direction by contacting the front main surface of the second holding member 216.

[0035] By the way, in the exhaust gas purification device 210, it is difficult to firmly fix the exhaust gas purification device 210 to the exhaust pipe 100. More specifically, the upper surface, lower surface, left surface, and right surface of the exhaust gas purification device 210 are in contact with the inner peripheral surface of the exhaust pipe 100. Therefore, if the areas of the upper surface, lower surface, left surface, and right surface of the exhaust gas purification device 210 are increased, the exhaust gas purification device 210 can be firmly fixed to the exhaust pipe 100. However, if the length of the exhaust gas purification device 210 in the front-rear direction increases in order to increase the areas of the upper surface, lower surface, left surface, and right surface of the exhaust gas purification device 210, the exhaust resistance increases.

[0036] Therefore, in the exhaust gas purification device 10, the length L2 of the first support portion 32 in the front-rear direction is longer than the length L1 of the reactor portion 30 in the front-rear direction. Thereby, the areas of the portions located above and below the first support portion 32 in the first holding member 14 and the second holding member 16 that contact the exhaust pipe 100 become larger. Therefore, the exhaust gas purification device 10 can be firmly fixed to the exhaust pipe 100. Furthermore, since the length L1 of the reactor portion 30 in the front-rear direction is short, an increase in the exhaust resistance is suppressed.

[0037] Further, the length of the reactor section 30 of the exhaust gas purification device 10 in the left - right direction can be made longer than the length of the reactor section of the exhaust gas purification device 210 in the left - right direction. More specifically, in the exhaust gas purification device 210, in order to fix the exhaust gas purification device 210 to the exhaust pipe, the upper surface, lower surface, left surface, and right surface of the exhaust gas purification device 210 are in contact with the inner peripheral surface of the exhaust pipe 100. In this case, in order to increase the areas of the upper surface, lower surface, left surface, and right surface of the exhaust gas purification device 210, the area of the reactor section becomes smaller. That is, the length of the reactor section in the left - right direction becomes shorter.

[0038] Therefore, in the exhaust gas purification device 10, the first support portion 32 and the second support portion 34 extend in the front - rear direction. Thus, if the lengths L2 and L3 of the first support portion 32 and the second support portion 34 in the front - rear direction are increased, even if the lengths of the first support portion 32 and the second support portion 34 in the left - right direction become shorter, the area where the exhaust gas purification device 10 contacts the exhaust pipe 100 is maintained. As a result, the length of the reactor section 30 in the left - right direction can be made longer.

[0039] In the exhaust gas purification device 10, the first holding member 14, the main body 12, and the second holding member 16 are stacked in the vertical direction. Therefore, when the exhaust gas purification device 10 is press - fitted into the exhaust pipe 100, the first holding member 14 is pushed downward by the upper surface of the exhaust pipe 100, and the second holding member 16 is pushed upward by the lower surface of the exhaust pipe 100. As a result, the first holding member 14, the main body 12, and the second holding member 16 are firmly held by the exhaust pipe 100 so as not to be separated. As a result, in the exhaust gas purification device 10, the metal fittings 110a and 110b of the exhaust gas purification device 210 are unnecessary.

[0040] According to the exhaust gas purification device 10, the occurrence of delamination between ceramic layers is suppressed. More specifically, in the main body 212, in the portion that overlaps with the first holding member 214 and the second holding member 216 in the front-rear direction, no electrodes and spaces are provided. In other words, in the main body 212, the regions where no electrodes and spaces are provided are located above and below the regions where electrodes and spaces are provided. In this case, the number of stacked layers of the main body 212 increases. When the number of stacked layers of the main body 212 increases, insufficient crimping is likely to occur during the manufacture of the main body 212. As a result, delamination between ceramic layers is likely to occur in the main body 212.

[0041] Therefore, in the exhaust gas purification device 10, the main body 12 does not overlap with the first holding member 14 and the second holding member 16 in the front-rear direction. Thus, the volume of the region where no electrodes and spaces are provided in the reactor unit 30 is minimized. Thus, an increase in the number of stacked layers of the main body 12 is suppressed, and the occurrence of delamination between ceramic layers is suppressed.

[0042] In the exhaust gas purification device 10, while firmly fixing the exhaust gas purification device 10 in the exhaust pipe 100, the PM removal performance of the exhaust gas purification device 10 can be improved. More specifically, in order to improve the PM removal performance of the exhaust gas purification device 10, the areas of the front and rear surfaces of the reactor unit 30 may be increased. However, when the areas of the front and rear surfaces of the reactor unit 30 increase, the length of the first support portion 32 and the second support portion 34 in the left-right direction becomes shorter, so the area where the exhaust gas purification device 10 contacts the exhaust pipe 100 becomes smaller. That is, it becomes difficult to firmly fix the exhaust gas purification device 10 in the exhaust pipe 100.

[0043] However, in the exhaust gas purification device 10, the first support portion 32 and the second support portion 34 extend in the front-rear direction. Therefore, if the lengths L2 and L3 of the first support portion 32 and the second support portion 34 in the front-rear direction are increased, the area where the exhaust gas purification device 10 contacts the exhaust pipe 100 becomes larger. That is, the exhaust gas purification device 10 can be firmly fixed in the exhaust pipe 100. As described above, in the exhaust gas purification device 10, while firmly fixing the exhaust gas purification device 10 in the exhaust pipe 100, the PM removal performance of the exhaust gas purification device 10 can be improved.

[0044] (Other Embodiments) The exhaust gas purification device according to the present invention is not limited to the exhaust gas purification device 10 and can be modified within the scope of the gist thereof.

[0045] Note that in the exhaust gas purification device 10, the main body 12 may not include the second support portion 34.

[0046] Note that the exhaust gas may flow forward.

[0047] Note that the first support portion 32 may protrude only in the forward direction from the reactor portion 30, or may protrude only in the rearward direction from the reactor portion 30.

[0048] Note that the second support portion 34 may protrude only in the forward direction from the reactor portion 30, or may protrude only in the rearward direction from the reactor portion 30.

[0049] Note that the first holding member 14 may not be in contact with the upper surface of the reactor portion 30. In this case, a member different from the first holding member 14 is in contact with the upper surface of the reactor portion 30 and the upper surface of the exhaust pipe 100.

[0050] Note that the second holding member 16 may not be in contact with the lower surface of the reactor portion 30. In this case, a member different from the second holding member 16 is in contact with the lower surface of the reactor portion 30 and the lower surface of the exhaust pipe 100.

Description of Reference Numerals

[0051] 10: Exhaust Gas Purification Device 12: Body 14: First holding member 16: Second holding member 18: Third holding member 20: Fourth holding member 30: Reactor section 32: First support section 34: Second support section 36-1 to 36-n, 38-1 to 38-n, 40-1 to 40-n-1: Ceramic layer 42-1 to 42-n, 44-1 to 44-n, 46-1 to 46-n, 48-1 to 48-n: Electrode layer 50-1 to 50-n, 51-1 to 51-n, 52-1 to 52-n, 53-1 to 53-n: Space 100: Exhaust pipe

Claims

1. The exhaust gas purification device includes a main body, The main body includes a reactor section and a first support section, The reactor section extends in the left-right direction, and a space through which exhaust gas passes in the front-rear direction is provided, PM contained in the exhaust gas is removed by plasma when passing through the space, The first support section extends in the front-rear direction and is connected to the left end of the reactor section, The length of the first support section in the front-rear direction is longer than the length of the reactor section in the front-rear direction, Exhaust gas purification device.

2. The exhaust gas purification device is disposed in an exhaust pipe, The exhaust gas purification device further includes a first holding member and a second holding member, The first holding member is in contact with the upper surface of the first support section and the upper surface of the exhaust pipe, The second holding member is in contact with the lower surface of the first support section and the lower surface of the exhaust pipe, The exhaust gas purification device according to Claim 1.

Images