JP2011185162A - Exhaust emission control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device supplying ozone generated by an ozone generation device into an exhaust pipe in a short time while preventing a failure of the ozone generation device. <P>SOLUTION: A circular opening portion 10 is formed in an end face 4b of a case 4a of the ozone generation device 4, and an opening peripheral edge 11 is provided along the opening portion 10. A disc-shaped filter member 7 is provided inside the opening peripheral edge 11. A circular hole portion 13 is formed in the exhaust pipe 2, and a hole peripheral edge 14 is provided along the hole portion 13. The opening peripheral edge 11 is inserted into the hole peripheral edge 14 and welded thereto along a contact area between the end face 4b of the case 4a and the end face of the hole peripheral edge 14 to form a connection portion 6. The ozone generation device 4 is connected directly to the exhaust pipe 2 in the state of locating the filter member 7 between the exhaust pipe 2 and itself. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an exhaust gas purification apparatus for an internal combustion engine.

  For example, Patent Documents 1 and 2 disclose exhaust gas purification apparatuses that purify NOx and particulate matter (PM) using ozone as an oxidizing agent. These exhaust gas purification apparatuses include an ozone generation apparatus that generates ozone. The ozone generation apparatus includes a pair of electrodes facing each other, applies a voltage between these electrodes, and air between these electrodes. To generate ozone.

JP 2008-75638 A JP 2006-257948 A

  However, in the exhaust gas purifying apparatus described in Patent Document 1, the ozone generator is connected to the exhaust pipe via the ozone discharge pipe, and the ozone generator is located away from the exhaust pipe. Since it takes time to be supplied from the device to the exhaust pipe, even if the amount of NOx discharged from the engine increases rapidly, even if the ozone supply amount of the ozone generator is increased accordingly, the exhaust pipe There was a time lag in the actual increase in the amount of ozone supplied to the plant, and there was a problem that it was not possible to respond quickly to a rapid increase in NOx. In addition, in the exhaust gas purification device described in Patent Document 2, the discharge port of the ozone generation device is directly connected to the exhaust pipe. However, since exhaust gas containing PM flows in the exhaust pipe, the exhaust gas flows into the ozone generation device. The problem was that it would flow in and cause a failure of the ozone generator.

  The present invention has been made to solve such problems, and provides an exhaust gas purifying device that can supply ozone generated by an ozone generator into an exhaust pipe in a short time and prevent failure of the ozone generator. The purpose is to do.

An exhaust gas purification apparatus according to the present invention includes exhaust gas purification means provided in an exhaust pipe through which exhaust gas discharged from an internal combustion engine flows, an ozone generation device that generates ozone, and a filter member. A filter member is provided directly in the pipe and in the connection between the ozone generator and the exhaust pipe. Since the ozone generating device is directly connected to the exhaust pipe, the distance from the ozone generating device to the exhaust pipe is shortened, and the filter member is provided in the connecting portion between the exhaust pipe and the ozone generating device. The member prevents PM in the exhaust gas from flowing into the ozone generator.
The ozone generation device includes an opening and an opening peripheral edge provided along the opening. The exhaust pipe includes a hole and a hole peripheral edge provided along the hole. The opening periphery and the hole periphery may be combined with each other and fixed.
The filter member may be provided in any one of the opening periphery and the hole periphery.
The ozone generation device includes an opening and an opening peripheral edge provided along the opening, the exhaust pipe includes a hole, and the connection portion is fixed while the opening peripheral is inserted into the hole. May be configured.
The filter member may be provided in the opening periphery.
The ozone generation device includes an opening, the exhaust pipe includes a hole and a hole peripheral part provided along the hole, and the connection part is fixed while the hole peripheral part is inserted into the opening. May be configured.
The filter member may be provided in the hole periphery.
An exhaust gas blocking means may be provided between the ozone generator and the filter member.

  According to the present invention, since the ozone generator is directly connected to the exhaust pipe, the distance from the ozone generator to the exhaust pipe is shortened, so that the ozone generated by the ozone generator can be quickly transferred to the exhaust pipe. Since the filter member is provided in the connection portion between the exhaust pipe and the ozone generation device, the filter member prevents PM in the exhaust gas from flowing into the ozone generation device. Can be prevented.

1 is a schematic configuration diagram of an internal combustion engine provided with an exhaust gas purification apparatus according to Embodiment 1 of the present invention. FIG. 6 is an enlarged cross-sectional view showing a modification of the configuration in which the ozone generator and the exhaust pipe are connected in the exhaust gas purifying apparatus according to Embodiment 1. FIG. 6 is an enlarged cross-sectional view showing a modification of the configuration in which the ozone generator and the exhaust pipe are connected in the exhaust gas purifying apparatus according to Embodiment 1. FIG. 5 is an enlarged cross-sectional view showing another modification of the configuration in which the ozone generator and the exhaust pipe are connected in the exhaust gas purifying apparatus according to Embodiment 1. FIG. 6 is an enlarged cross-sectional view showing a modification of the configuration in which the ozone generator and the exhaust pipe are connected in the exhaust gas purifying apparatus according to Embodiment 2. FIG. 6 is an enlarged cross-sectional view showing a modification of the configuration in which the ozone generator and the exhaust pipe are connected in the exhaust gas purifying apparatus according to Embodiment 2. FIG. 9 is an enlarged cross-sectional view showing another modification of the configuration in which the ozone generator and the exhaust pipe are connected in the exhaust gas purifying apparatus according to Embodiment 2. FIG. 9 is an enlarged cross-sectional view showing a modification of the configuration in which the ozone generator and the exhaust pipe are connected in the exhaust gas purifying apparatus according to Embodiment 3.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
Embodiment 1 FIG.
FIG. 1 shows a schematic configuration diagram of an internal combustion engine equipped with an exhaust gas purifying apparatus according to Embodiment 1 of the present invention. An exhaust pipe 2 through which exhaust gas flows is connected to a diesel engine 1 that is an internal combustion engine. The exhaust pipe 2 is provided with a NOx storage catalyst 3 that is an exhaust gas purification means. Further, on the upstream side of the NOx storage catalyst 3, the ozone generator 4 is directly connected to the exhaust pipe 2, and a connecting portion 6 is configured between the ozone generator 4 and the exhaust pipe 2. A filter member 7 is provided inside the connecting portion 6. The ozone generator 4 has a pair of electrodes 8 and 8 provided so as to face each other with a gap therebetween, and each of the electrodes 8 and 8 is connected to the power supply device 5 by an electric wire.

As shown in FIG. 2 (a), the ozone generator 4 has a cylindrical case 4 a having an outer diameter D. A circular opening 10 is formed on one end face 4b of the case 4a, and a cylindrical opening peripheral edge 11 is provided along the opening 10 so as to protrude from the end face 4b. A disc-shaped filter member 7 having a diameter the same as the inner diameter d _1i of the opening peripheral edge 11 is provided inside the opening peripheral edge 11. On the other hand, a circular hole portion 13 is formed in the exhaust pipe 2, and a cylindrical hole peripheral edge portion 14 protrudes from the exhaust pipe 2 outward in the radial direction of the exhaust pipe 2 along the hole portion 13. Is provided. The outer diameter d _1o of the opening peripheral portion 11 is substantially the same as the inner diameter d _2i of the hole peripheral portion 14, and the opening peripheral portion 11 can be inserted into the hole peripheral portion 14. Further, the outer diameter d _2o of the hole peripheral portion 14 is the same as the outer diameter D of the case 4a. Further, the length L ₁ of the opening peripheral edge 11 in the direction protruding from the end face 4 b is substantially the same as the length L ₂ of the hole peripheral edge 14 in the radial direction of the exhaust pipe 2.

  As shown in FIG. 2 (b), the opening peripheral edge 11 is inserted into the hole peripheral edge 14 and welded along the contact portion between the end face 4 b of the case 4 a and the end face of the hole peripheral edge 14. Part 6 is configured. That is, the connecting portion 6 is configured by combining the opening peripheral edge portion 11 and the hole peripheral edge portion 14 together and fixing them. Thereby, since the ozone generator 4 is directly connected to the exhaust pipe 2, the distance from the ozone generator 4 to the exhaust pipe 2 becomes as short as possible.

  As described above, since the ozone generating device 4 is directly connected to the exhaust pipe 2, the distance from the ozone generating device 4 to the exhaust pipe 2 is shortened, so that the ozone generated by the ozone generating device 4 can be reduced in a short time. The filter member 7 can be supplied to the exhaust pipe 2, and the filter member 7 is provided in the connection portion 6 between the exhaust pipe 2 and the ozone generator 4, so that the PM in the exhaust gas can be supplied to the ozone generator 4. Since the inflow is prevented, a failure of the ozone generator 4 can be prevented.

  In Embodiment 1, the hole peripheral edge portion 14 is provided so as to protrude outward in the radial direction of the exhaust pipe 2 from the exhaust pipe 2, but is not limited to this form. As shown in FIG. 3, the hole peripheral edge portion 14 ′ may be provided so as to extend toward the inside of the exhaust pipe 2. In this case, the opening peripheral edge portion 11 is inserted into the hole peripheral edge portion 14 ′, and welding is performed along the contact portion between the end surface 4b of the case 4a and the end surface of the hole peripheral edge portion 14 ′, whereby the connecting portion 6 is configured. Is done.

  In the first embodiment, the hole peripheral edge portion 14 protrudes outward in the radial direction of the exhaust pipe 2 from the exhaust pipe 2, or the hole peripheral edge portion 14 ′ extends toward the inside of the exhaust pipe 2. However, it is not limited to this form. As shown in FIG. 4, a hole peripheral portion 14 ″ having the same thickness as the wall thickness of the exhaust pipe 2 may be provided along the hole 13 inside the hole 13. The connection portion may be configured by inserting the opening peripheral edge portion 11 into the hole portion 13 and welding along the contact portion between the end surface 4b of the case 4a and the outer peripheral surface of the exhaust pipe 2 without providing the portion.

  In the first embodiment, the opening peripheral edge 11 and the hole peripheral edge 14 are fixed by welding, but the present invention is not limited to this form. A male screw part is formed on the outer peripheral surface of the opening peripheral part 11 and a female screw part is formed on the inner peripheral surface of the hole peripheral part 14, and the ozone generating device 4 is rotated by inserting the opening peripheral part 11 into the hole peripheral part 14. Thus, the opening peripheral edge portion 11 and the hole peripheral edge portion 14 may be fixed by screwing the male screw portion and the female screw portion.

Embodiment 2. FIG.
Next, an exhaust gas purification apparatus according to Embodiment 2 of the present invention will be described. In the following embodiments, the same reference numerals as those in FIGS. 1 to 4 are the same or similar components, and thus detailed description thereof is omitted.
The exhaust gas purifying apparatus according to Embodiment 2 of the present invention is connected to Embodiment 1 by providing the filter member 7 inside the hole periphery 14 and inserting the hole periphery 14 into the opening periphery 11. The part 6 is configured.

As shown in FIG. 5A, a circular opening 10 is formed on one end surface 4 b of the case 4 a of the ozone generator 4, and a cylindrical opening peripheral edge 11 is formed along the opening 10. It is provided so as to protrude from the ozone generator 4. On the other hand, a circular hole portion 13 is formed in the exhaust pipe 2, and a cylindrical hole peripheral edge portion 14 protrudes from the exhaust pipe 2 outward in the radial direction of the exhaust pipe 2 along the hole portion 13. Is provided. The inner diameter d _1i of the opening peripheral edge 11 is substantially the same as the outer diameter d _2o of the hole peripheral edge 14, and the hole peripheral edge 14 can be inserted into the opening peripheral edge 11. A circular filter member 7 having a diameter equal to the inner diameter d _2i of the hole peripheral portion 14 is provided inside the hole peripheral portion 14.

  As shown in FIG. 5B, by inserting the hole peripheral portion 14 into the opening peripheral portion 11 and welding along the contact portion between the end surface of the opening peripheral portion 11 and the outer peripheral surface of the exhaust pipe 2, A connection unit 6 is configured. Thereby, since the ozone generator 4 is directly connected to the exhaust pipe 2, the distance from the ozone generator 4 to the exhaust pipe 2 becomes as short as possible, and the connection between the exhaust pipe 2 and the ozone generator 4 is possible. By providing the filter member 7 in the part 6, the filter member 7 prevents the PM in the exhaust gas from flowing into the ozone generator 4. Therefore, also in the second embodiment, the same effect as in the first embodiment can be obtained.

  In the second embodiment, the opening peripheral edge 11 is provided so as to protrude from the ozone generator 4, but is not limited to this form. As shown in FIG. 6, the opening peripheral edge 11 ′ may be provided so as to extend toward the inside of the ozone generator 4. Further, as shown in FIG. 7, an opening peripheral portion 11 ″ having the same thickness as the wall thickness of the case 4a may be provided along the opening 10. Furthermore, without providing the opening peripheral portion. The connecting portion may be configured by inserting the hole peripheral portion 14 into the opening 10.

  In the second embodiment, the opening peripheral edge 11 and the hole peripheral edge 14 are fixed by welding, but the present invention is not limited to this form. A male screw portion is formed on the outer peripheral surface of the hole peripheral portion 14 and a female screw portion is formed on the inner peripheral surface of the opening peripheral portion 11. The hole peripheral portion 14 is inserted into the opening peripheral portion 11 to rotate the ozone generator 4. Thus, the opening peripheral edge portion 11 and the hole peripheral edge portion 14 may be fixed by screwing the male screw portion and the female screw portion.

  In the first and second embodiments, the opening 10 and the hole 13 are each circular, but are not limited to this shape. As long as they have the same shape, any shape such as a square may be used. The opening peripheral edge portion 11 and the hole peripheral edge portion 14 are also provided along the opening portion 10 and the hole portion 13, respectively, and thus have the same shape as the opening portion 10 and the hole portion 13.

  In the first and second embodiments, the opening peripheral edge portion 11 and the hole peripheral edge portion 14 insert the opening peripheral edge portion 11 into the hole peripheral edge portion 14 or insert the hole peripheral edge portion 14 into the opening peripheral edge portion 11. However, the present invention is not limited to this form. You may combine by welding the contact part so that the end surface of the opening peripheral part 11 and the end surface of the hole peripheral part 14 may contact | connect, or to each of the end surface of the opening peripheral part 11 and the end surface of the hole peripheral part 14 These may be combined by forming arbitrary concave and convex shapes that can be fitted to each other and welding the contact portions so that the concave and convex shapes are fitted to each other. That is, you may combine the opening peripheral part 11 and the hole peripheral part 14 with what kind of form.

Embodiment 3 FIG.
Next, an exhaust gas purification apparatus according to Embodiment 3 of the present invention will be described. The exhaust gas purifying apparatus according to Embodiment 3 of the present invention is different from Embodiment 1 in that exhaust gas blocking means is provided between the ozone generator 4 and the filter member 7.
As shown in FIG. 8, an open / close valve 30 serving as an exhaust gas blocking means is connected to the end surface 4b of the case 4a. The on-off valve 30 may be any form of valve such as a manual valve or a solenoid valve. The opening / closing valve 30 is provided with an opening peripheral edge 11 on the side opposite to the ozone generator 4, and a filter member 7 is provided inside the opening peripheral edge 11. Other configurations are the same as those of the first embodiment.

  Similarly to the first embodiment, the opening peripheral edge portion 11 is inserted into a hole peripheral edge portion 14 (see FIG. 2 (a)) provided in the exhaust pipe 2 (see FIG. 2 (a)) and welded. The ozone generator 4 is connected to the exhaust pipe 2 in a state where the on-off valve 30 is disposed between the pipe 2 and the pipe 2. When there is no need to supply ozone depending on the operating condition of the diesel engine 1 (see FIG. 1), it is possible to reliably prevent PM in the exhaust gas from flowing into the ozone generator 4 by closing the on-off valve 30. In the third embodiment, the distance from the ozone generator 4 to the exhaust pipe 2 is short, and the filter member 7 is provided between the exhaust pipe 2 and the ozone generator 4. 1 can be obtained.

  In the third embodiment, the filter member 7 is provided inside the opening peripheral portion 11 and the opening peripheral portion 11 is inserted into the hole peripheral portion 14. However, the present invention is not limited to this configuration. The filter member 7 may be provided inside the hole periphery 14 and the hole periphery 14 may be inserted into the opening periphery 11. Further, instead of fixing the opening peripheral edge 11 and the hole peripheral edge 14 by welding, a male screw part and a female screw part are provided in the opening peripheral edge part 11 or the hole peripheral edge part 14, and the male screw part and the female screw part are screwed together. The opening peripheral edge 11 and the hole peripheral edge 14 may be fixed.

  In Embodiment 3, the open / close valve 30 that communicates and shuts off the ozone generator 4 and the exhaust pipe 2 is employed as the exhaust gas shut-off means. However, the present invention is not limited to this. Any type of exhaust gas can be used as long as it blocks the flow of ozone into the ozone generator 4, for example, a check that ensures the flow from the ozone generator 4 to the exhaust pipe 2 but blocks the flow in the reverse direction. It may be a valve.

  In the first to third embodiments, the connection between the opening peripheral edge portion 11 and the hole peripheral edge portion 14 is performed by welding or screwing the male screw portion and the female screw portion provided in the welding peripheral portion. It is not limited. An arbitrary method such as a known adhesive or a fixing member may be employed as long as it can be reliably fixed in a state where the opening peripheral edge portion 11 and the hole peripheral edge portion 14 are combined with each other. In the first to third embodiments, the NOx occlusion catalyst 3 has been described as an example of the exhaust gas purifying means. However, the present invention is not limited to this. The exhaust gas purification means may be an SCR catalyst of a urea SCR system or a diesel particulate filter (DPF).

  DESCRIPTION OF SYMBOLS 1 Diesel engine (internal combustion engine), 2 exhaust pipe, 3 NOx occlusion catalyst (exhaust gas purification means), 4 ozone generator, 6 connection part, 7 filter member, 10 opening part, 11, 11 ', 11 "opening peripheral part, 13 hole part, 14, 14 ', 14 "hole peripheral part, 30 on-off valve (exhaust gas cutoff means).

Claims (8)

Exhaust gas purification means provided in an exhaust pipe through which exhaust gas discharged from the internal combustion engine flows;
An ozone generator for generating ozone;
A filter member,
The exhaust gas purification device, wherein the ozone generator is directly connected to the exhaust pipe, and the filter member is provided in a connection portion between the ozone generator and the exhaust pipe. The ozone generator includes an opening and an opening peripheral edge provided along the opening,
The exhaust pipe includes a hole portion and a hole peripheral portion provided along the hole portion,
The exhaust gas purification device according to claim 1, wherein the connection portion is configured by combining and fixing the peripheral edge portion of the opening and the peripheral edge portion of the hole.   The exhaust gas purifying apparatus according to claim 2, wherein the filter member is provided inside one of the peripheral edge of the opening and the peripheral edge of the hole. The ozone generator includes an opening and an opening peripheral edge provided along the opening,
The exhaust pipe includes a hole,
The exhaust gas purifying apparatus according to claim 1, wherein the connection portion is configured such that the peripheral edge portion of the opening is inserted into the hole portion and fixed.   The exhaust gas purifying apparatus according to claim 4, wherein the filter member is provided in the peripheral edge of the opening. The ozone generator includes an opening,
The exhaust pipe includes a hole portion and a hole peripheral portion provided along the hole portion,
The exhaust gas purifying apparatus according to claim 1, wherein the connection portion is configured by inserting and fixing the peripheral edge portion of the hole into the opening portion.   The exhaust gas purifying apparatus according to claim 6, wherein the filter member is provided in a peripheral portion of the hole.   The exhaust gas purification apparatus according to any one of claims 1 to 7, wherein an exhaust gas blocking means is provided between the ozone generator and the filter member.

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