JP2602092Y2 - Particulate trap - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a particulate trap for purifying exhaust gas from an engine of an automobile or the like.

Here, a particulate trap (Part
iculate Trap) refers to a device that adsorbs and collects particulate matter such as carbon particulates contained in the exhaust gas of an engine, purifies the exhaust gas and then discharges it. Device ".

[0003] After traveling, the particulate trap needs to be regenerated, ie, an operation of removing trapped particulate matter is required, and there have been various structural problems in the prior art.

[0004]

2. Description of the Related Art Examples of the disclosure of the structure of a particulate trap are disclosed in JP-A-59-153913, JP-A-2-118121, and JP-A-4-217.
No. 17 publication.

FIG. 3 shows a cross-sectional view of a particulate trap according to the prior art. In the figure, C is a main body of the particulate trap, that is, a can body. The can body C is usually made of metal having a cylindrical or elliptical cylindrical shape, and has an exhaust gas inlet a and an exhaust gas outlet b.
And a flange B, respectively, to the exhaust gas flow upstream and downstream exhaust passages. FIG. 3 is a sectional view assuming that the particulate trap is cut along a vertical plane passing through the axis of the can C.

In FIG. 1, reference numeral 1 denotes a trap filter (collecting filter), 2 denotes a heater wire (heating wire), 3 denotes a heat insulating material for holding a heater, 4 denotes a heat insulating material, 5 denotes a heater terminal, and 6 denotes a heater terminal. A temperature sensor 13 is a diffuser (diffuser) of the can body C.

[0007] The following is a description of particulate matter according to the prior art.
The operation of the trap will be described. Particulate /
The operation of the trap has two aspects. The first is a particulate matter collecting operation, and the second is a regenerating operation.

First, the first particulate matter trapping operation is an essential operation of the particulate trap mainly performed during traveling. In FIG. 3, the exhaust gas flowing from the exhaust gas inlet a flows in from the exhaust gas inflow surface of the trap / filter 1 on the side near the exhaust gas inlet a, and particles such as carbon fine particles mixed therein. Substances are adsorbed. The purified exhaust gas is discharged into the atmosphere via the exhaust gas outlet surface of the trap filter 1 on the side close to the exhaust gas outlet b and the exhaust gas outlet b.

A large number of horizontal lines shown in the trap filter 1 are a collection of thin walls (hereinafter, a space formed by enclosed walls is called a cell). FIG. 4 is an enlarged sectional view assuming that one of the cells is cut along a plane passing through its axis. The wall material is a porous ceramic, which is formed by a pore wall E, a cell opening e, and a plugging material F as shown in the figure. , Penetrating from inside the cell to outside the cell. Therefore, the exhaust gas flowing from the cell opening e follows the path shown by the arrow in the figure and passes through the myriad of pores and is discharged. At this time, the particulate matter mixed in the exhaust gas passes through the pores. It cannot pass and is absorbed here. The set of filter cells in FIG. 3 is arranged such that the cell openings e of the adjacent filter cells and the plugging material F are alternately arranged.

Next, the second regenerating operation is an auxiliary operation of the particulate trap mainly performed in the garage after traveling. That is, due to the particulate matter trapping operation performed during traveling, the pores are filled with the adsorbed particulate matter, and if used continuously without any treatment, the pores are blocked by the particulate matter and the exhaust gas is exhausted. Is difficult to use and cannot be used. Therefore, the particulate trap after the particulate matter trapping operation needs to be treated so that the particulate matter adsorbed on the trap filter is removed and used again with good performance. This measure is reproduction, and the operation for reproduction is the reproduction operation.

The regenerating operation is usually performed by connecting a power source outside the automobile to the heater terminal 5 in FIG. As shown in the figure, the heater wire 2 is disposed so as to be very close to or in contact with the outer periphery of the trap filter 1 and is fixed by a heater holding insulating material 3. The temperature of the heater can be detected by the temperature sensor 6, and the inner wall of the can C is covered with a heat insulating material 4 so that the exhaust gas and the heat of the heater are not conducted to the outside of the can C.

Trap filter 1 with heater wire 2
Is heated, the particulate matter is burned, vaporized and removed. At this time, the heating temperature is slowly increased, and in this case, the amount of auxiliary combustion air (air supplied for combustion) flowing through the exhaust gas inflow / outflow ports a and b is limited to perform gentle combustion. This is an essential condition for obtaining a high-performance reproduction operation.

[0013]

However, according to the above-mentioned prior art, however, "it is not easy to replace the trap filter", and since the trap filter is exposed to high-pressure exhaust gas, "high discharge" is required. It is difficult to hold and fix to withstand the gas pressure. "In addition, since the trap filter is heated directly from the outer periphery by the heater wire," a local temperature difference occurs at the outer periphery. " Cracks "and" there is a local difference in the regenerating effect due to this temperature difference ".

Therefore, the object of the present invention is to easily replace the trap filter, to withstand high pressure, to produce fine cracks on the outer peripheral portion and to reduce the regeneration effect, except for the above-mentioned disadvantages of the prior art. The aim is to provide a particulate trap that does not cause local differences.

[0015]

According to the present invention, francs are provided at both ends.
And a can body with a cylindrical body
Can body with diffuser parts arranged respectively on both sides of the body
Is constituted, and a heater wire is held in the can body.
A heater chamber is disposed, and one end of the heater chamber is provided in the heater chamber.
Make the fixed flange project outward from the can body
At the other end with an inner flange facing inward
The inner case is arranged so that it can be pulled out along the axial direction.
And a trap filter is provided in the inner case.
Is fixed, and one flange of the can body and the one die are fixed.
Between the fuser section and the fixed type franc of the inner case
The jig is pinched and bolted through a gasket,
Inner flange of the inner case and the other diffuser
A detachable flange is projected between the
And the removable flange is attached to the inner flange of the inner case.
The inside of the flange is bolted to the other end of the can.
The attachment and detachment between the lung and the other diffuser part
The outer part of the mold flange is clamped, and through the gasket
It is characterized by being bolted.

[0016]

First, for the first particulate matter collecting operation, since the trap filter is fixed in the inner case (inner housing), the trap filter withstands a high exhaust gas pressure and is held and fixed. Is done. Also, one of the flags of the can body
Between the nozzle and one of the diffusers
The fixed flange is clamped and the gasket
Since it is bolted via sealing packing)
Exhaust gas does not leak from the can. The other side of the can
Removable flange between the flange and the other diffuser
The outer part of the flange is pinched, and the bolt is
Since it is stopped , exhaust gas does not leak from the can body.

Next, for the second regeneration operation, since the trap filter is indirectly heated via the inner case wall, a local temperature difference is generated at the outer peripheral portion of the trap filter. There is no occurrence of fine cracks and no local difference in reproduction effect. When replacing the trap filter, first replace the can
After removing the diffuser part, remove the bolt and remove
By removing the mold flange from the inner case,
Pull out the filter from the can with the inner case
You.

[0018]

FIG. 1 is a partial sectional view showing the structure of an embodiment of a particulate trap according to the present invention. In the figure, cans
The body D is provided on both sides of the can body D1 and the can body D1.
And diffusers 13 and 13
You. The can body body D1 is made of a cylindrical or elliptical cylindrical metal.
With flanges D2 and D3 formed at both ends, respectively.
Become. Also, one diffuser located on the left side of FIG.
A flange 13A is formed in the portion 13 corresponding to the flange D2.
And the other diffuser section 13 located on the right side of FIG.
A flange 13B is formed corresponding to the flange D3.
I have. The diffusers 13 and 13 have an exhaust gas inlet a and an exhaust gas outlet b, respectively, and are connected to the exhaust gas upstream and downstream exhaust passages via a flange A and a flange B, respectively. Same as the prior art.
In addition, FIG. 1 is a side view showing the appearance of the particulate trap for a portion above a horizontal plane passing through the axis of the can body D, and the lower portion also passes through the axis of the can D. FIG. 4 is a cross-sectional view assuming that the lower half of the particulate trap is cut in a vertical plane.

In the figure, 1 is a trap filter, 2 is a heater wire, 3 is a heat insulating material for holding a heater made of asbestos (asbestos), 4 is a heat insulating material also made of asbestos, 5 is a heater terminal, and 6 is a temperature. It is a sensor .

As a new part, 7 is an inner case, 8 is a heater chamber, 9 is a wire mesh (wire mesh), 10 is a fixed flange, 11 is a detachable flange, and 12 is a gasket made of asbestos.

As shown in FIG . 1 and FIG.
The data chamber 8 is arranged. Inner case in heater room 8
7 is arranged so as to be able to be pulled out along the axial direction. I
A fixed type flange 10 is provided at one end of the female case 7.
Toward the outside of the can body D and at the other end
The inner flange 7A is formed inward. Said b
Inner flange 7A of the inner case 7 and the other diffuser part
13, the detachable flange 11 is projected outside the can body D.
It is arranged. The trap filter 1 is fixed in the inner case 7, and the heater wire 2 is held in the heater chamber 8. Since the trap filter 1 is fixed in the inner case 7, even if the trap filter 1 is exposed to a high exhaust gas pressure, the trap filter 1 is mechanically firmly held. In order to make the temperature distribution on the outer periphery of the trap filter 1 more uniform and at the same time protect the outer periphery mechanically, in this embodiment, the heat conductivity and the buffering property are provided between the trap filter 1 and the inner wall of the inner case 7. A good wire mesh 9 is inserted. Further, since the heater wire 2 is held and fixed in the heater chamber 8 in the vicinity of the inner case 7 and the heat generated by the heater wire 2 does not reach the can D, the heater chamber 8 has The heat insulating material 3 is filled. Since the heater chamber 8 is completely covered with the wall and is isolated from the exhaust flow, the particulate matter in the exhaust gas does not adhere to the heater wire 2 and does not cause a short circuit or a short circuit. Furthermore, can body D
Is covered with the heat insulating material 4, so that the exhaust gas and the heat of the heater are not conducted to the can D.

One flange D2 of the can body D and one flange D2
The inner case 7 is located between the fuser 13 and the flange 13A.
Fixed type flange 10 is sandwiched and
Bolted. Inner case 7 inner flange
The inner part 11A of the detachable flange 11 is bolted to 7A.
ing. The other flange D3 of the can D and the other diffuser
Between the detachable flange 11 and the flange 13B of the
Outer part 11B is clamped and bolts are inserted through gasket 12.
It has been stopped. Accordingly, when it is difficult to regenerate the trap filter 1 or when it is necessary to use a trap filter 1 that has already been regenerated because there is not enough time to regenerate, etc., the operation of removing or tightening the bolt 14 is performed. , trap filter 1 is replaced easily and in a short time together with the inner case 7. Moreover, since the bolting is performed via the gasket 12 , the exhaust gas does not leak from the can body D after the fastening.

[0023] Then, when replacing the trap filter 1 first after removal of the diffuser portion 13 of the can body D, by removing the bolts 14 of the detachable flange 11,
It can be withdrawn in together and the inner case 7 on the left side of the can body D.

FIG. 2 shows the diffuser section as described above.
After having removed the 13, a trap filter 1 fixed to the inner case 7 together with the inner case 7, showing the way of extracting from the can body D to the left of the can body D, the status of each separate member schematically It is a partial sectional view. The method for creating this partial cross-sectional view is exactly the same as that in FIG.

[0025]

As described above, according to the present invention, the trap filter is firmly held against high exhaust gas pressure, is easy to replace, and the exhaust gas does not leak from the can body. A particulate trap that does not cause fine cracks on the outer peripheral portion of the filter and does not cause a local difference in regeneration effect can be realized.
Also, when the trap filter is difficult to regenerate or regenerate
Trap fills that have already been played because there is no time to spare
If you want to use a bolt, remove or tighten the bolt
The trap filter with the inner case.
Can be easily and quickly replaced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

2 is a partial cross-sectional view of the way of extracting the trap filter.

FIG. 3 is a cross-sectional view of a conventional particulate trap.

FIG. 4 is a sectional view of a filter capillary.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Trap filter 2 Heater wire 3 Heat insulation material for heater 4 Heat insulation material 5 Heater terminal 6 Temperature sensor 7 Inner case 8 Heater room 9 Wire mesh 10 Fixed flange 11 Removable flange 12 Gasket 13 Diffuser part 14 Bolt

Continuation of the front page (72) Inventor Tadashi Ishii 1-chome, 1-chome, Ageo-shi, Saitama Nissan Diesel Kogyo Co., Ltd. (56) References JP-A 2-31330 (JP, U) JP-U 4-76921 ( (JP, U) Shokai Sho 61-74616 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) F01N 3/02 F01N 7/18 F01N 9/00

Claims (1)

(57) [Scope of request for utility model registration] 1. A cylinder having flanges formed at both ends.
Shaped can body, and placed on each side of the can body
And a diffuser section, the heater chamber having a heater wire held in the can body.
Is disposed inside the heater chamber with a fixed flange at one end.
To the outside of the can body and the inner end to the other end.
The inner case with the flange facing inward is the axis
The trap filter is fixed inside the inner case.
And one of the flanges of the can body and the one of the diffuser portions.
Between the fixed type flange of the inner case
And the inner case is bolted via a gasket.
A detachable flange is projected between the
Placed on the inner flange of the inner case,
The inner portion is bolted, and the other flange of the can body and the other diffuser portion
Between, the outer portion of the detachable flange is sandwiched,
A particulate trap which is bolted through a gasket .