JP2003172119A - Exhaust emission control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simultaneously eliminate failures in a conventional three-piece type exhaust emission control device. <P>SOLUTION: This device is provided with a filter cassette 23 unitized by integrally holding a particulate filter 6 by an inner shell 22, a first outer cylinder 25 arranged opposite to the cassette 23 and a second outer cylinder 28 internally fixing and equipped with an outer shell 26 slidably and internally receiving and holding the cassette 23. The second outer cylinder 28 is formed to have an outside diameter larger than that of each flange 25a and 23a for the mutual first outer cylinder 25 and cassette 23. A contact ring 29 for latching a flange 23a of the cassette 23 when inserting the cassette 23 into the shell 26 from an anti-flange 23a side is provided on an inner periphery of a first outer cylinder 25 opposite end part in the second outer cylinder 28. Both of the flanges 25a and 23a are attachably/detachably fastened on the contact ring 29. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust emission control device.

[0002]

2. Description of the Related Art Particulate Matter (Particulate Matter) emitted from a diesel engine is
Soot composed of carbonaceous matter and SO composed of high boiling hydrocarbon components
The main component is the F component (Soluble Organic Fraction), and a slight amount of sulfate (mist-like sulfuric acid component) is also included in the composition. As a measure for reducing this type of particulates, FIG. As shown in, the exhaust pipe 4 through which the exhaust gas 3 from the diesel engine 1 flows
It is considered to equip the particulate filter 6 in the middle of.

In the example shown here, oxidation is carried out in a muffler 5 of an exhaust pipe 4 in which exhaust gas 3 discharged from a diesel engine 1 (internal combustion engine) of an automobile via an exhaust manifold 2 flows. The case where a catalyst regeneration type particulate filter 6 in which a catalyst is integrally supported is accommodated is illustrated. The particulate filter 6 is shown.
The filter case 7 that holds the outer wall of the muffler 5 is configured as an outer cylinder.

That is, the muffler 5 is enlarged as shown in FIG.
Between the inlet pipe 8 and the outlet pipe 9 of the above, a storage space of a required size defined by the dispersion plates 10 and 11 having a large number of communication holes is secured, and the particulate filter 6 is placed in this storage space. Are to be accommodated.

The particulate filter 6 has a porous honeycomb structure made of ceramic, and the inlets of the flow passages 6a partitioned in a grid pattern are alternately plugged, and the inlet is not plugged. The outlet of the passage 6a is plugged so that only the exhaust gas 3 that has permeated through the porous thin wall 6b that defines each passage 6a is discharged to the downstream side.

The particulates collected on the inner surface of the porous thin wall 6b of the particulate filter 6 are self-combusted and removed in an operating region where the exhaust gas temperature is high, or if necessary. Although it will be burned and removed with the help of some heating means provided, the particulate filter 6 will gradually accumulate ash generated by combustion in the cylinder due to the lubricating oil, and therefore particulates will be collected. It is necessary to directly clean the filter 6 by air cleaning, water cleaning, or the like, or replace it with a new particulate filter 6.

For this reason, the filter case 7 is divided into a front portion 12, an intermediate portion 13 and a rear portion 14 and the bolts 15 and nuts 1 are separated from each other by the flanges 12a, 13a and 14a.
A structure in which the particulate filter 6 is detachably fastened is adopted, and the particulate filter 6 can be appropriately removed together with the intermediate portion 13 for cleaning or replacement.

In the intermediate portion 13 of the filter case 7, the particulate filter 6 is restrained from moving in the axial direction by engaging the outer edges of the inlet end face and the outlet end face of the particulate filter 6 with the end plates 17. In addition, the outer peripheral surface of the net material 18 is held by a net material 18 (cushion material) formed by weaving a metal wire material such as stainless steel. The sealing material 19 is interposed so as to prevent the bypass of the exhaust gas 3.

[0009]

However, in such a three-part conventional structure, the intermediate portion 13 holding the particulate filter 6 must be removed unless the bolts are fastened at the two front and rear attachment / detachment points. Therefore, there is a problem that the particulate filter 6 cannot be easily cleaned or replaced, and
The flanges 12a, 13a, 14 are attached at two front and rear attachment / detachment points.
In addition to the fact that a is required, it causes an increase in weight, and since there are more places where sealing is required, it becomes difficult to maintain the airtightness, and it takes time and effort for the fastening work to easily cause mistakes such as forgetting to close the bolt 15. It was

Further, in the case where the conventional muffler arrangement space is used to provide a sound deadening function together with the purpose of mounting the muffler on the vehicle, interference with the frame is avoided and an appropriate minimum ground height (load) is set. As a result of the maximum outer diameter for ensuring the (clearance) being defined by the flanges 12a, 13a, 14a, the body portion of the filter case 7 forming the outer cylinder of the muffler 5 becomes thinner by the amount of the flanges 12a, 13a, 14a. There is also a problem that the volume of the silencing chambers 20 and 21 formed before and after the particulate filter 6 becomes small.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a new exhaust gas purification device capable of simultaneously solving various problems in the conventional three-division type exhaust gas purification device. There is.

[0012]

DISCLOSURE OF THE INVENTION The present invention is an exhaust gas purifying apparatus which is installed in the middle of an exhaust pipe to remove particulates in exhaust gas, and which holds a particulate filter integrally by an inner shell. A unitized filter cassette, a first outer cylinder arranged so as to face the filter cassette, and a second outer cylinder internally fixedly equipped with an outer shell capable of slidably fitting and holding the filter cassette. A first outer cylinder and a filter cassette are formed with flanges that are abutted against each other at opposite end portions of the first outer cylinder and the filter cassette, and the second outer cylinder is formed so that the outer diameter is larger than the respective flanges. In the second outer cylinder, an abutment ring for locking the flange of the filter cassette when the filter cassette is inserted into the outer shell from the side opposite the flange is provided. Provided circumferentially opposite end portion of the one outer cylinder, is characterized in that it said entered into the flanges of the contact ring and the second outer tube and filter cassettes detachably.

Thus, in this way, the first outer cylinder can be removed from the second outer cylinder only by releasing the fastening state between the contact ring of the second outer cylinder and the flanges of the first outer cylinder and the filter cassette. It becomes possible to remove the filter cassette from the outer shell in the second outer cylinder by separating it from the cylinder, and it becomes possible to easily clean or replace the particulate filter.

Further, by consolidating the attachment / detachment locations into one location, it is possible to reduce the number of flanges and reduce the weight, and the number of locations requiring sealing is reduced, so that the airtightness can be easily maintained. Furthermore, the labor required for the fastening work is saved, and negligence such as forgetting to close the bolts is less likely to occur.

Further, in the present invention, the end of the second outer cylinder facing the first outer cylinder is formed so as to project toward the first outer cylinder side with respect to the contact ring, and the first outer cylinder and the filter cassette are formed. It is preferable that a gap be secured between the outer peripheral surfaces of both flanges and the end portion of the second outer cylinder facing the first outer cylinder.

[0016] With this structure, the fastening portion between the flange of the first outer cylinder and the flange of the filter cassette or between the flange of the filter cassette and the contact ring of the second outer cylinder is loosened by any chance. Even if the generated exhaust gas leaks from one another, the leaked exhaust gas collides with the inner peripheral surface of the end portion of the second outer cylinder facing the first outer cylinder and is guided to the gap. A flow of exhaust gas in a relatively safe direction is formed along the body of the first outer cylinder, and the risk of surrounding components being exposed to high-temperature exhaust gas and burning out is avoided.

Further, it is preferable that the inner spaces of the first outer cylinder and the second outer cylinder form a muffling chamber. By doing so, the muffler can also have a muffling function so that the conventional muffler can be arranged. It becomes possible to mount it on a vehicle that uses space, and yet, while maintaining the maximum outer diameter that is not much different from the conventional three-part type, the outer diameter of the inner space on the second outer cylinder side is secured to ensure a large silencer chamber. It is possible to increase the capacity.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

1 to 4 show an example of an embodiment for carrying out the present invention, and the portions denoted by the same reference numerals as those in FIG. 6 represent the same things.

In the exhaust gas purification apparatus of the present embodiment shown in FIGS. 1 to 4, a filter cassette 23 unitized by integrally hugging the particulate filter 6 with the inner shell 22, and a front stage of the filter cassette 23. A first outer cylinder 25 that is disposed in the inner wall of the filter housing 23 to define a muffling chamber 24, and an outer shell 26 that slidably fits and holds the filter cassette 23 therein, and a filter cassette that is fitted and held in the outer shell 26. A second outer cylinder 28 that defines a silencing chamber 27 behind 23.

Further, flanges 25a and 23a that are abutted against each other are formed at the mutually opposing ends of the first outer cylinder 25 and the filter cassette 23, and the outer diameter is larger than these flanges 25a and 23a. The second outer cylinder 28 is formed so that.

Further, an abutment ring 29 is provided on the inner circumference of the second outer cylinder 28 on the front end side so as to engage the flange 23a of the filter cassette 23 when the filter cassette 23 is inserted into the outer shell 26 from the front side. , The stud bolts 3 are provided at a plurality of circumferential positions of the contact ring 29.
0 is projected toward the front, and the nut 3 is passed through the stud bolts 30 through the flanges 25a and 23a.
The first outer cylinder 25, the filter cassette 23, and the second outer cylinder 28 can be removably assembled at one place by fastening with 1.

Here, particularly in the present embodiment, the front end of the second outer cylinder 28 is formed so as to project forward of the contact ring 29, and both flanges of the first outer cylinder 25 and the filter cassette 23 are formed. A gap S is secured between the outer peripheral surfaces of 25a and 23a and the front end portion of the second outer cylinder 28.

The holding structure of the particulate filter 6 with respect to the inner shell 22 of the filter cassette 23 is substantially the same as the conventional case described above, and the outer edges of the inlet side end face and the outlet side end face of the particulate filter 6 are end. It is locked by the plate 17 so as to be restrained from moving in the axial direction, and the outer peripheral surface portion thereof is held by a net material 18 (cushion material) formed by weaving a metal wire material such as stainless steel. A sealing material 19 is provided at an intermediate position in the axial direction of the net material 18 so that the exhaust gas 3 can be prevented from bypassing.

Further, the structure for holding the filter cassette 23 with respect to the outer shell 26 of the second outer cylinder 28 will be described in detail. The front end portion (the front end portion in the insertion direction) of the filter cassette 23 is fixed and held by the flange 23a as described above. While firmly fixed, the rear end of the filter cassette 23 (the rear end in the insertion direction) is located inside the outer shell 26 that faces the outer periphery of the rear end of the inner shell 22 when the filter cassette 23 is mounted. The guide ring 32 is press-fitted into and held by a guide ring 32 provided on the circumferential surface. The guide ring 32 has a tapered shape in which the diameter gradually decreases in the insertion direction of the filter cassette 23, and the tip end thereof is formed. The inner shell 22 is narrowed down so as to substantially match the outer periphery of the rear end portion.

Moreover, a stopper ring 33 is formed on the outer peripheral surface of the inner shell 22 at a position shifted forward from the rear end portion by a required length so as to form a brim, and the stopper ring 33 and the guide ring are provided. Between the ring 32 and a net material 34, which is formed by weaving a metal wire material such as stainless steel,
The (cushion material) is interposed so as to be held by the filter cassette 23 when the filter cassette 23 is mounted.

Further, the outer shell 26 and the inner shell 2
A net material 35 similar to the net material 34 is interposed at the front side of the space formed between the two materials, and the ceramic material is provided in the space between the front and rear net materials 35, 34. Mat material 36 made of heat-resistant fiber such as fiber
(Cushion material that also has a sealing function) is interposed.

In the figure, 37 and 38 are heat insulating materials for suppressing the temperature drop of the particulate filter 6,
Reference numerals 39 and 40 denote gaskets, respectively.

Thus, if the exhaust emission control device is constructed in this manner, the first outer cylinder 25 can be simply released by releasing the fastening state between the abutment ring 29 and the flanges 25a and 23a by the stud bolt 30 and the nut 31. The filter cassette 23 can be extracted from the outer shell 26 in the second outer cylinder 28 by separating the filter cassette 23 from the second outer cylinder 28, and the particulate filter 6 can be easily cleaned and replaced.

Further, by consolidating the attachment / detachment locations into one location, the number of flanges can be reduced and the weight can be reduced, and the number of locations requiring sealing can be reduced, making it easy to maintain airtightness. As a result, the labor required for the fastening work can be saved, and negligence such as forgetting to close the nut 31 is unlikely to occur.

Further, particularly in this embodiment, it is assumed that the fastening portion between the flanges 25a and 23a or between the flange 23a and the contact ring 29 is loosened and the exhaust gas 3 leaks out. Also, the leaked exhaust gas 3 collides with the inner peripheral surface of the front end portion of the second outer cylinder 28 and is guided to the gap S, and the exhaust gas 3 along the body portion of the first outer cylinder 25 in a relatively safe direction. Therefore, the risk that the peripheral parts are exposed to the high temperature exhaust gas 3 and burned is avoided in advance.

Further, it is possible to secure a large outer diameter of the muffling chamber 27 behind the particulate filter 6 while maintaining the maximum outer diameter which is not much different from the conventional three-part type, so that the muffling chamber has a conventional capacity. It will be greatly increased.

As described above, according to the present embodiment, the first outer cylinder 25 is separated from the second outer cylinder 28 only by releasing the fastening state between the contact ring 29 and the flanges 25a, 23a. Since the cassette 23 can be pulled out, cleaning and replacement of the particulate filter 6 can be easily performed, moreover, the number of flanges can be reduced to achieve weight reduction, and a portion requiring sealing can be reduced to provide an airtight seal. The safety can be improved by facilitating the retention of the properties, omitting the time and effort required for the fastening work, and making it difficult for the nut 31 to forget to close the nut 31.

Further, even if the exhaust gas 3 leaks out due to looseness at the joints between the flanges 25a and 23a or between the flanges 23a and the contact ring 29, the leaked exhaust gas will leak out. Since the flow of No. 3 can be changed by the front end portion of the second outer cylinder 28 in a relatively safe direction along the body of the first outer cylinder 25, peripheral parts are exposed to the hot exhaust gas 3 and burned out. It is possible to avoid the possibility of occurrence of the noise, and to secure a large outer diameter of the muffling chamber 27 behind the particulate filter 6 while maintaining the maximum outer diameter which is not much different from the conventional three-part type. Capacity can also be increased.

The exhaust gas purification apparatus of the present invention is not limited to the above-mentioned embodiment, and it is not necessary to have a muffler as a muffling function, and the exhaust gas is not shown in the drawings. Needless to say, the flow may be reversed, and other various changes may be made without departing from the scope of the present invention.

[0036]

According to the exhaust gas purification apparatus of the present invention described above, various excellent effects as described below can be obtained.

(I) According to the invention described in claim 1 of the present invention, the fastening state between the abutment ring of the second outer cylinder and the both flanges of the first outer cylinder and the filter cassette is simply released. Since the one outer cylinder can be separated from the second outer cylinder and the filter cassette can be extracted from the outer shell in the second outer cylinder, cleaning and replacement of the particulate filter can be easily performed.

(II) According to the invention described in claim 1 of the present invention, the number of flanges can be reduced and the weight can be reduced by consolidating the attachment / detachment locations at one location, and a seal is required. The safety can be improved by reducing the number of parts to facilitate maintaining the airtightness, save the labor required for the fastening work, and prevent the negligence such as forgetting to close the bolt or the like from occurring.

(III) According to the invention described in claim 2 of the present invention, between the flange of the first outer cylinder and the flange of the filter cassette, or between the flange of the filter cassette and the contact ring of the second outer cylinder. Even if looseness occurs in the fastening portion between the exhaust gas and the exhaust gas leaking from one another, the leaked exhaust gas flow is caused by the end portion of the second outer cylinder facing the first outer cylinder. Since it is possible to change to a relatively safe direction along the body of the first outer cylinder, it is possible to avoid the risk of surrounding components being exposed to high-temperature exhaust gas and burning.

(IV) According to the invention described in claim 3 of the present invention, by providing the muffler with the sound deadening function, the conventional muffler can be mounted on a vehicle utilizing the space for arranging the muffler. Moreover, it is possible to increase the capacity of the muffling chamber by maintaining a large outer diameter of the internal space on the second outer cylinder side while maintaining the maximum outer diameter that is not much different from the conventional three-part type.

[Brief description of drawings]

FIG. 1 is a partial sectional view showing an example of an embodiment for carrying out the present invention.

FIG. 2 is an enlarged sectional view showing a fixed state of a front end portion of the filter cassette shown in FIG.

FIG. 3 is an enlarged sectional view showing a fixed state of a rear end portion of the filter cassette of FIG.

FIG. 4 is a perspective view showing a state in which the first outer cylinder and the second outer cylinder of FIG. 1 are separated.

FIG. 5 is a schematic view showing a conventional example.

6 is a partial cross-sectional view showing a detailed structure of the filter case of FIG.

[Explanation of symbols]

3 exhaust gas 4 exhaust pipe 6 Particulate filter 22 Inner Shell 23 Filter cassette 23a flange 24 Noise reduction chamber (exhaust diffusion chamber) 25 First outer cylinder 25a flange 26 Outer shell 27 Noise reduction chamber (exhaust gas collection chamber) 28 Second outer cylinder

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Makoto Tsujida             3-1, Hinodai, Hino City, Tokyo 1 Hino             Inside the automobile corporation (72) Inventor Hisashi Tohsaka             3-1, Hinodai, Hino City, Tokyo 1 Hino             Inside the automobile corporation (72) Inventor Toshiki Oya             3-1, Hinodai, Hino City, Tokyo 1 Hino             Inside the automobile corporation (72) Inventor Daisuke Shirai             3-12-3 Nakamachidai, Tsuzuki-ku, Yokohama-shi, Kanagawa             Universal Cata Systems Co., Ltd. F-term (reference) 3G090 AA02 BA01 BA08 EA01                 4D058 JA32 JB06 KA03 KA16 KC22                       SA08

Claims (3)

[Claims] 1. An exhaust purification device, which is provided in the middle of an exhaust pipe to remove particulates in exhaust gas, comprising a filter cassette unitized by integrally holding a particulate filter with an inner shell. A first outer cylinder arranged so as to face the filter cassette, and a second outer cylinder fixedly equipped with an outer shell capable of slidably fitting and holding the filter cassette therein,
The first outer cylinder and the filter cassette are formed with flanges that are abutted against each other at mutually opposing ends, and the second outer cylinder is formed so that the outer diameter is larger than the respective flanges, and the filter shell is provided with respect to the outer shell. A contact ring that locks the flange of the filter cassette when the filter is inserted from the side opposite to the flange is provided on the inner periphery of the end of the second outer cylinder facing the first outer cylinder, and the contact ring and the second outer cylinder are provided. And an exhaust purification device characterized in that both flanges of the filter cassette are detachably fastened. 2. An outer peripheral surface of both flanges of the first outer cylinder and the filter cassette, wherein an end of the second outer cylinder facing the first outer cylinder is formed so as to project beyond the contact ring toward the first outer cylinder. And a gap is secured between an end portion of the second outer cylinder facing the first outer cylinder.
The exhaust emission control device according to. 3. The exhaust emission control device according to claim 1 or 2, wherein the internal spaces of the first outer cylinder and the second outer cylinder form a muffling chamber.