JPS6118175Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an improvement in a catalytic converter for purifying automobile exhaust gas.

(Prior Art) Generally, an automobile exhaust system has a long conduit 1 that communicates with an exhaust manifold (not shown), as shown in FIG. A catalytic converter 2 is provided, and a muffler 3 is provided downstream thereof.

As shown in FIG. 2, a conventional catalytic converter 2 has a structure in which a catalyst main body 5 is housed in a casing 4 via a holding member 6 made of stainless wire mesh. The holding material 6 functions as a buffer material for the catalyst body 5. In addition, the axial end of the catalyst body 5 is designed to prevent exhaust gas from passing between the catalyst body 5 and the casing 4, to prevent the catalyst body 5 from moving in the axial direction, and to provide a buffering function. A cushioning material 7 is attached around the part. This buffer material 7 is a material called a stainless steel sponge made by compressing thin stainless steel wire, or a material made by compressing glass wool, rock wool, etc.
It is denser and almost impermeable to exhaust gases. Note that in order to easily attach and detach such a catalytic converter 2 to and from the conduit 1, the casing 4 is
Pipe joint flanges 9 are formed at both axial ends of the pipe.

The casing 4 is composed of a pair of shells 4a and 4b that are integrated into a cylindrical body. each shell 4
As shown in FIG. 3, a and 4b have mating surface flange portions 10a and 10b formed at their joint portions to protrude in the radial direction. And this pair of Ciel 4
a and 4b are body portions 8 formed approximately at the center in the axial direction;
The catalyst main body 5 was housed inside through a stainless steel wire mesh 6, and then the middle skins were placed together (hereinafter referred to as
The mating surface flange portions 10a and 10b are brought into abutment by abbreviated as "middle matching"). After that, the pipe fitting flange 9 is fitted to both ends of the shells 4a, 4b in the axial direction, and the respective mating surface flange portions 10a, 10b and the pipe fitting flange 9 are fitted.
The catalytic converter 2 is assembled by brazing or welding the joints.

(Problems to be Solved by the Invention) However, since the catalyst body 5 is made of ceramic, it is difficult to make the outer diameter dimension accurately constant, and the catalyst body 5 has variations in manufacturing dimensions. I had no choice but to use it. For this reason, for example,
After the catalyst body 5, which is formed larger than the design dimensions, is housed in the shells 4a and 4b and the shells 4a and 4b are aligned, when fitting the flanges 9, 9 to both ends, the catalyst body 5 is The outer periphery is each shell 4a,
The catalyst body 5 was strongly pressed by the inner circumferential wall of the catalyst body 4b, causing cracks or distortions, and there was a risk that the catalyst body 5 would be damaged during use. In addition, the catalyst body 5, which is formed smaller than the design size, is attached to the shells 4a and 4b.
If the catalyst body 5 was housed inside the casing, the holding force of the catalyst body 5 would be insufficient, and there was a risk that the catalyst body 5 would shift toward the inside of the casing.

As described above, the conventional casing 4 cannot absorb variations in the manufacturing dimensions of the catalyst body 5, and it takes a lot of effort to eliminate this and produce a predetermined product.

This invention was made in view of the above points,
Even if there is some variation in the manufacturing dimensions of the catalyst body, the casing side will change to match the catalyst body.
To provide a catalytic converter that can be installed in a casing without distorting or damaging the catalyst body and without rattling.

(Means for Solving the Problems) In order to achieve the above object, the present invention stores a catalyst main body in a body located approximately at the axial center of a casing formed by fitting a pair of shells together. , forming a diff user part that continuously reduces the casing diameter from both ends of the body part, and fixing a pipe fitting flange to a flange connecting end formed at at least one end in the axial direction of the casing constituted by these parts. In the catalytic converter, a side edge extending in the circumferential direction is formed at the mating surface of the pair of shells, and the side edge formed on one shell is made closer to the side edge formed on the other shell. is formed to be wide in the radial direction, and the other side edge is slidably accommodated within the one side edge, and between the body of either or both of the shells and the flange connection end. The invention is characterized in that a notch is formed in the mating surface portion of the differential user portion located at , and both side edges formed on the pair of shells and the mating surface portion are fixed to each other.

(Function) According to the present invention having such a configuration, even if the outer diameter of the catalyst body is formed to be slightly larger or smaller due to manufacturing errors, when the catalyst body is fitted together and housed within the body of the casing, the side edges of the pair of shells that make up the casing slide circumferentially to absorb the manufacturing errors, so that the catalyst body can be installed within the casing without being distorted or damaged, and without any rattling.

(Example) An example of the present invention will be described below with reference to the drawings.

4 and 5 are exploded perspective views showing an example of the catalytic converter according to the present invention, and the same members as those shown in FIGS. 2 and 3 are given the same reference numerals.

This catalytic converter 20 or Atsupashiel 21
A casing 21 consisting of a and a lower shell 21b
A large-diameter body 8 is formed approximately at the center of the casing 21 in the axial direction to accommodate the catalyst main body 5 having a flat, oval cross section. Diffuser parts 22, 22 are formed to continuously reduce the casing diameter. moreover,
In this embodiment, small-diameter cylindrical parts 25a having substantially the same diameter as the small-diameter conduit 1 shown in FIG. 1 are formed at both ends of the diff user parts 22, 22. The casing 21 formed in this way has
Pipe coupling flanges 9, 9 are fixed to the flange connecting end 25b at the end of the small diameter cylindrical portion 25a, and the small diameter conduit 1 shown in FIG. 1 is connected via these flanges 9, 9. It's summery.

Both shells 21a and 21b of this casing 21
There are no mating surface flanges 10a, 10b as shown in FIG.
Side edges 23a and 23b are formed extending in the circumferential direction, and these are configured to come into sliding contact with each other. That is, as shown in FIG.
When the side edge 23b of the shell 1b is formed wider in the radial direction than the side edge 23a of the shell 21a, and the two shells are aligned in the middle, the side edge 2 of the shell 21a
3b slides into the lower shell 21b.

However, this mating surface portion 23 is similar to the small diameter cylindrical portion 25.
a. In the flange connecting portion 25 where the flange 9 is attached, the circumferential end surfaces 24 thereof are not in sliding contact but are in contact with each other, and this portion is inscribed in the bore 9a of the pipe fitting flange 9. ing.

Further, the flange connecting end portion 25 configured in this manner
A notch 26 is formed in the mating surface portion 23 of the duplex user portion 22 between the body portion 8 and the body portion 8. The reason for providing this notch 26 is that in the body 8,
The attupa shell 21a and the lower shell 21b have different diameters so that they slide into contact with each other and overlap, whereas the differential user part 22 and the small diameter cylindrical part 25a
In this case, the mating surface parts 23, 23 are not brought into sliding contact and overlapped, but their circumferential end faces 24 are brought into contact with each other. This is due to the fact that it is necessary to provide a discontinuous point at which the diameter of the mating surface portions 23, 23 changes. That is, at the cut 26, the front and rear diameters of the mating surface portion 23 are different, and on the body 8 side, both the mating surface portions 22, 23 of the upper and lower shells are formed with the different diameters. The side edges 23a and 23b overlap, and on the side of the small diameter cylindrical portion 25, the diameters are made the same and they abut at the end surface 24.

Furthermore, if the catalyst body 5 is formed larger or smaller than the designed dimensions, or if it is not a regular elliptical cylinder but is distorted, the overlapping state of the upper and lower shells 21a and 21b will be This appears as vertical deformation in the short diameter direction of the main body 5, and in the latter case, both shells 2 are distorted due to horizontal distortion in the long diameter direction or longitudinal distortion in the axial direction.
This appears as left and right, front and back deformation of 1a and 21b, but such deformation is absorbed by the notch 26.

Furthermore, since the flange 9 is tightly attached to the flange connecting end 25b, it is press-fitted with a fairly strong force, but the stress caused by this press-fitting is absorbed by the notch 2.
6, the signal is not transmitted to the trunk 8.

When the catalyst main body 5, which is molded to have an outer diameter slightly larger than the design dimension, is housed in the casing 21, the side edges 23 formed on each shell 21a, 21b of the body 8 slide in the circumferential direction. It becomes possible to absorb manufacturing errors in the catalyst body 5 and to hold the catalyst body 5 without applying abnormal pressure to the catalyst body 5.

In addition, when storing the catalyst main body 5 molded with an outer diameter slightly smaller than the design dimension in the casing, the side edge 23 of the upper shell 21a in the body 8 is circumferentially inserted into the side edge 23 of the lower shell 21b. The catalyst body 5 can be held without creating an unnecessary gap between the catalyst body 5 and the casing 21 by sliding in the direction. In the small diameter cylindrical portion 25a, since the circumferential end surfaces 24 of the small diameter cylindrical portion 25a abut each other, one shell does not enter the other shell. A notch 26 is provided to prevent the small diameter cylindrical portion 25a and the body portion 8 from deforming integrally.

Note that, from the purpose of the present invention, the notch 26 is
Since it is necessary that they overlap at least in the body part 8, it is desirable to form it in a portion that moves from the body part 8 to the differential user part 22. However, depth of cut 2
6 does not necessarily have to be this part, and may be formed anywhere as long as the mating surface part 23 of the differential user part 22 is formed due to production and design considerations.

In this way, after installing the catalyst body 5, which is not manufactured to the same design dimensions, into the shell 12 so as not to apply unnecessary stress, the pipe fitting flange 9 is press-fitted into the flange connection end 25b, Furthermore, each mating surface part, that is, the overlapping fitting part of the body part 8, the abutting part of the diffuser part 22 and the small diameter cylindrical part 25, the press-fit part of the pipe fitting flange 9, and the notch 26 are made by brazing, welding, etc. Stick to it,
Complete the catalytic converter.

In this embodiment, a small-diameter cylindrical portion is provided adjacent to the differential user portion, but the small-diameter cylindrical portion may be omitted and the differential user portion may be continuously inclined from the body portion to the flange connection end.

(Effects of the invention) As is clear from the above explanation, according to the invention, when a catalyst body with a large manufacturing error is housed in a casing of a predetermined shape, The formed side edges slide against each other in the circumferential direction, absorbing manufacturing errors in the catalyst body, and fixing the catalyst body within the casing without distorting or damaging the catalyst body, and without rattling it. becomes possible. Moreover, since a notch is formed between the body of the casing and the flange connection end, even if the flange for a pipe fitting is tightly attached to the flange connection end, it can be press-fitted with quite strong force.
Stress due to this press-fitting is not transmitted to the body, and damage to the catalyst body that occurs conventionally when fitting a pipe joint flange to a flange connection end can be avoided.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a general exhaust system, Fig. 2 is a front view showing a cross section of the upper half of a conventional catalytic converter, Fig. 3 is a cross-sectional equivalent view taken along the - line in Fig. 2, and Fig. 4 is a perspective view showing a general exhaust system. The figure is an exploded perspective view showing one embodiment of the present invention, and FIG. 5 is a sectional view showing the assembled state of the same embodiment.
6 is a sectional view taken along the - line in FIG. 5, and FIG. 7 is an enlarged view of section A in FIG. 5. 5... Catalyst body, 8... Body, 9... Pipe joint flange, 20... Catalytic converter, 21... Casing, 21a... Atsupashiel, 21b...
Loisiel, 22...Deaf User Club, 23...
Matching surface portions, 23a, 23b...Side edge portions, 25a...
...Small diameter cylindrical part, 25b...Flange connection end, 2
6...notch.

Claims (1)

[Scope of utility model registration request] The catalyst main body 5 is housed in a body part 8 located approximately at the center in the axial direction of the casing 21 formed by bringing together a pair of shells 21a and 21b, and the casing diameter is continuously reduced from both ends of the body part 8. In the catalytic converter, the pipe fitting flange 9 is fixed to a flange connecting end 25 formed at at least one end in the axial direction of a casing constituted by the diff user parts 22, 22 having a diameter. Side edges 23a and 23b extending in the circumferential direction are formed on the shell mating surface portion 23, and a side edge 23b formed on one shell 21b and a side edge 23a formed on the other shell 21a.
The other side edge portion 2 is formed wider in the radial direction than the
3a is slidably accommodated in one side edge 23b, and the differential user portion located between the body 8 and the flange connection end 25 of one or both of the shells 21a, 21b. A catalytic converter characterized in that a notch 26 is formed in the mating surface portion 23, and both side edge portions 23a, 23b formed on the pair of shells and the mating surface portion are fixed to each other.