JPS61274829A - Assembly method of catalytic converter - Google Patents

Abstract

PURPOSE:To make it possible to prevent catalytic carrier bodies from breakage by constituting a shell with both ends of built-in assembled bodies fixed to the inner faces of both half bodies of a shell remaining the built-in assembled bodies compressed at a constant load in their axial direction and with both half bodies of the shell welded to be combined. CONSTITUTION:With the opposed ends of catalytic carrier bodies 2 lying next to each other, elastic rings 13 are brought into contact, between which a set plate 14 is provided. And with the peripheral edge sections of the end faces at the sides where both catalytic carrier bodies 2 are separated from each other, the elastic rings are brought into contact which are supported by end face set plates 15 fixed to the inner faces of both ends of a shell3 in their axial direction. And each part to be contained in the shell 3 is collected in assembling a catalytic converter composing built-in assembled bodies 16. That is, the built-in assembled bodies 16 are composed in such a way that the elastic rings 13, catalytic carrier bodies 2, elastic rings 13, and end face set plates 15 are brought into contact with both sides the set plate 14 at the middle in order respectively.

Description

Detailed Description of the Invention A6 Object of the Invention (1) Industrial Field of Application The present invention relates to a cylindrical shell formed by welding together circumferential ends of a pair of shell halves each having an arcuate cross section. A plurality of catalyst carriers supporting a catalyst while allowing gas flow are housed and arranged on the same axis at intervals, and each catalyst carrier is placed on both axial end faces of each catalyst carrier. The present invention relates to a method of assembling a catalytic converter in which elastic rings for elastically holding the converter are abutted from both ends in the axial direction.

(21 Prior Art) Conventionally, in such a catalytic converter, as shown in FIG.
The catalyst carrier 2, which has elastic rings 13 in contact with the peripheral edges of both axial end faces thereof, is fitted into the positioning grooves 26.

(3) Problems to be Solved by the Invention Incidentally, the elastic ring 13 is compressed when fitting into the positioning groove 26 and holds the catalyst carrier 2 with its elastic force, but the elastic ring 13 has a large elastic force. If it is too much, the catalyst carrier 2 may be damaged. For this reason, it is necessary to strictly define the axial length 11 of the positioning groove 26 and the length 12 of the catalyst carrier 2, but this is actually difficult in terms of production technology.

In addition, the purification characteristics of a catalytic converter in which a plurality of catalyst carriers 2 are arranged depends on the distance between each catalyst carrier 2! 3, but in the conventional shell 25, the shell 25 is pressed, so the accuracy of the positioning grooves 26 and the spacing 14 cannot be expected to be very high, and as mentioned above, the position of the catalyst carrier 2 is also unstable. Therefore, the interval 14 is also unstable.

Furthermore, since the positioning groove 26 is provided in the shell 25, a constriction is created, and in order to ensure durability that can withstand stress concentration on the constriction, the thickness of the shell 25 must be made relatively large. No.

The present invention was made in order to solve the above-mentioned conventional problems, and it is possible to maintain a constant spacing between each catalyst carrier even if the dimensional accuracy of the shell is relatively poor (even if the dimensional accuracy of the shell is relatively poor), and it is possible to prevent damage to the catalyst carriers. It is an object of the present invention to provide a method for assembling a catalytic converter, which prevents this and also allows durability and reliability to be obtained even if the thickness of the shell is made relatively small.

B0 Structure of the Invention (1) Means for Solving the Problems In the method of the present invention, a set plate is interposed between the elastic rings that contact the opposing end surfaces of adjacent catalyst carriers, so that a plurality of catalyst carriers are arranged in a straight line. an elastic ring is arranged in the shell, and elastic rings are also brought into contact with the end faces of the catalyst carrier at both ends in the arrangement direction, thereby forming an insert assembly to be housed in the shell;
Both ends of the insert assembly are fixed to the inner surfaces of both shell halves while the insert assembly is compressed with a constant load in the axial direction, and the shell halves are welded together to form a shell. did.

(2) Action By compressing the insert assembly with a constant load in the axial direction, each catalyst carrier is held by the elastic rings on both sides under a constant load, and the elastic rings and the set The dimensional accuracy of the plate is improved (thereby, the spacing between each catalyst carrier is constant. Moreover, since it is fixed to both shell halves at both ends of the insert assembly and both shell halves are joined, each catalyst carrier is The carriers are housed in the shell while keeping the distance between them constant, and the shell only needs to be cylindrical, and the plate thickness can be relatively thin.

(3) Examples Examples of the present invention will be explained below with reference to the drawings.
First, in FIG. 1 showing an embodiment of the present invention, this catalytic converter is installed, for example, in the middle of the exhaust system of a vehicle internal combustion engine, and a casing 1 has a plurality of catalyst carriers, for example, a pair of catalyst carriers 2. 2 are housed and arranged coaxially with a space between them. Both catalyst carriers 2, 2 support the catalyst while allowing the flow of exhaust gas, and are formed in a cylindrical shape, and as the exhaust gas flows through these catalyst carriers 2, 2, the EC in the exhaust gas is reduced. , CO and NOx are removed by promoting oxidation and reduction reactions.

The casing 1 has end cones 4 and 5 at both ends of the shell 30.
are welded together, and a flange 6.7 for joining to the middle of the exhaust pipe is fixed to both end cones 4.5.

In FIG. 2, the shell 3 is formed into a cylindrical shape by welding together shell halves 8 and 9 having semicircular cross sections. That is, joint flanges 10 and 11 that abut each other are integrally provided at both circumferential ends of both shell halves 8 and 9, and by abutting and welding these joint flanges 10 and 11, the shell is assembled. 3 is formed.

A ring-shaped peripheral surface protection member 12 made of an elastic material is interposed between the outer peripheral surface of each catalyst carrier 2, 2 and the inner peripheral surface of the shell 3, respectively. This peripheral surface protection member 12 is formed by, for example, knitting thin metal wires into a mesh shape, and serves to prevent the catalyst carrier 2.degree. 2 from being destroyed by vibration.

An elastic ring 1 is provided on the periphery of the opposing end surfaces of both catalyst carriers 2, 2.
3.13 are abutted and these elastic rings 13.
A set plate 14 is interposed between 13. The set plate 14 is formed into a ring shape with a substantially U-shaped cross section that opens inward.

Further, an elastic ring 13 having the same shape as the elastic ring 13 is provided at the peripheral edge of the end face of both the catalyst carriers 2, 2 on the sides that are separated from each other.
．． 13 are in contact with each other, and these elastic rings 13,1
3 is supported by end face set plates ts and is fixed to the inner surfaces of both axial ends of the shell 3.

These end face set plates 15.15 are formed into a ring shape with a cross-sectional shape, and are welded and fixed to the inner surface of the shell 3 at the position where each elastic ring 13 is compressed with a constant load. . As a result, each catalyst carrier 2, 2 is held with a constant elastic force from both ends in the axial direction.

Each part housed in the shell 3 is assembled for assembly of the catalytic converter.1. An interpolation aggregate 16 is constructed.

That is, the interpolation assembly 16 is
The elastic ring 13/catalyst carrier 2, the elastic ring 13, and the end face set plate 15 are abutted on both sides of 40 in this order.

Next, to explain the operation of this embodiment, when assembling the catalytic converter, the insert assembly 16 is prepared as shown in FIG. Ingredients 17. suppressed with a constant load by ill,
Compress. This compressive force is set to such an extent that damage to each catalyst carrier 2 due to the elastic force exerted by each elastic ring 13 can be avoided.

With the interpolation assembly 16 compressed in this way, the shell halves 8 and 9 are placed over the interpolation assembly 16 from both sides, and the interpolation assembly 1
6 both end face set play) 15. i5 to shell half 8,
The shell 3 is fixed by welding to the inner surfaces of both axial ends of the shell 9, and the shell halves 8 and 9 are welded to each other to form the shell 3. Thereafter, the pressed state by the pressing jigs 17 and 18 is released.

When welding i5.15 to the shell halves 8゜9, a plurality of holes are drilled at intervals in the circumferential direction at both ends of the shell halves 8 and 90, and the end faces are welded from the outside. Plate) 15.15 may be welded, or spot welding may be used. Further, the center set plate 14 may be welded to both shell halves 8, 9, or may be in a free state relative to both shell halves 8, 9.

Thereafter, the catalytic converter assembly process is completed by welding the entcos 74, 5 having flanges 6.degree. 7 to both axial ends of the shell 3.

According to such an assembly procedure, the catalyst carriers 2, 2 can be held under a constant load, regardless of the processing accuracy of the shell 3, that is, the shell halves 8, 9, and the length of the catalyst carrier 2°2. Therefore, damage to the catalyst carriers 2, 2 can be prevented.

In addition, since the set plate 14 and each elastic ring 13 are formed by single-piece processing, high-precision processing is possible. The interval between them is always constant.

Therefore, it is easy to set the interval to a value that can maximize the purification performance.

Furthermore, the longitudinal dimensional accuracy of the shell 3 and the shell halves 8, 9 is relatively rough because both ends of the insert assembly 16 are welded and fixed to the shell halves 8, 9, which is advantageous in terms of production technology. It is.

Moreover, since the shell 3 is formed in a cylindrical shape, there is no fin (therefore, stress concentration does not occur), so the plate thickness can be relatively thin.

FIG. 4 shows another embodiment of the present invention, and parts corresponding to those in the previous embodiment are given the same reference numerals.

Shell 3/ is formed by welding together a pair of shell halves 81 and 91, and these shell halves 8/ and 9/ are
A semi-conical portion 23.24 is integrally connected to one end of the semi-cylindrical portion 19.20 via a shoulder portion 21.22.

In this embodiment, the interpolation assembly 16'l is the same as the end face set plate 15 at one end of the interpolation assembly 16 in the previous embodiment.
It is formed by omitting the interpolation assembly 16' during assembly.
The elastic ring 13 on one end side of both shell halves g/, 9/
, and presses the insert assembly 16' from the other end side with a constant load.

While maintaining the suppressed state, the end face set plate 15 on the other end side of the interpolation assembly 16' is inserted into the shell half 8'.

9', and both shell halves 8'.

9 are welded and connected to each other to form a shell 3', and after releasing the suppressed state, an end cone 5 is attached to the other end of the shell 3'.
The assembly process is completed by welding and joining.

This embodiment can also provide the same effects as the above-mentioned embodiments.

In each of the above embodiments, a catalytic converter having a pair of catalyst carriers has been described, but the present invention is also applicable to a converter having three or more catalyst carriers.

C0 Effects of the Invention As described above, according to the method of the present invention, a plurality of catalyst carriers are arranged in a straight line by interposing a set plate between the elastic rings that contact the opposing end surfaces of adjacent catalyst carriers, respectively. Elastic rings are also in contact with the end faces of the catalyst carrier at both ends in the arrangement direction to form an insert assembly to be housed in the shell, and the insert assembly is compressed with a constant load in the axial direction. Both ends of the insert assembly are fixed to the inner surfaces of both shell halves, and both shell halves are welded together to form a shell, so that the catalyst carrier can be loaded with an appropriate load regardless of the dimensional accuracy of the shells. The catalyst carrier can be maintained in a heated state, the production technology is easy, quality can be stabilized and costs can be reduced, and damage to the catalyst carrier can be prevented. Further, the distance between the catalyst carriers can be kept constant, and the purification performance can be improved. Furthermore, the shell can be made into a simple cylindrical shape, thereby preventing the occurrence of stress concentration, so that the plate thickness can be made relatively thin, thereby reducing weight and cost.

[Brief explanation of the drawing]

Figures 1 to 3 show one embodiment of the present invention.
The figure is a longitudinal side view of the catalytic converter, and Figure 2 is the n of Figure 1.
-II line sectional view, FIG. 3 is a vertical sectional view showing the assembled state, FIG. 4 is a vertical sectional side view of a catalytic converter according to another embodiment of the present invention, and FIG. 5 is a longitudinal sectional view of the main part of the conventional technology. It is a diagram. 2... Catalyst carrier, 3, 3'... Shell, 8.8'
, 9°9'...Half shell, 13...Elastic ring,
14...Set plate, 16, 16'...Interpolated assembly patent applicant Honda Motor Co., Ltd. Procedural Amendment (Mutsu) December-2, 1985

Claims (1)

[Claims] In a cylindrical shell formed by welding together the circumferential ends of a pair of shell halves each having an arcuate cross section, a plurality of catalyst carriers supporting a catalyst while allowing gas flow are spaced apart from each other. A method for assembling a catalytic converter in which the catalyst carriers are housed and arranged on the same axis, and elastic rings for elastically holding each catalyst carrier from both axial ends are in contact with both axial end faces of each catalyst carrier. In this method, a plurality of catalyst carriers are arranged in a straight line by interposing a set plate between the elastic rings that contact opposite end faces of adjacent catalyst carriers, and elastic rings are also provided on the end faces of the catalyst carriers at both ends in the arrangement direction. are brought into contact with each other to form an interpolation assembly to be housed in the shell, and with the interpolation assembly compressed with a constant load in the axial direction, the insertion assembly is placed on the inner surface of both shell halves. A method for assembling a catalytic converter, characterized in that both ends are fixed and both shell halves are welded together to form a shell.