JP2001030019A - Manufacture of storage case of exhaust gas purifying catalyst - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the axial length of an inclined wall part of a tip reduced cylindrical part while ensuring the axial length of an exhaust gas purifying catalyst, and to suppress generation of machining defects such as wrinkles on the inclined wall part of the tip reduced cylindrical part. SOLUTION: In a manufacturing method of a storage case of an exhaust gas purifying catalyst 80, a metal cylindrical body 1 haring one end 1a and the other end c extended in the direction of the axial P1 to form an opening and its inner part forming catalyst storage space 1d is spinning-formed using a tool, a stepped shoulder part 15 which is along the direction orthogonal to the axis P1 of the cylindrical body 1 and opposite to an end part 80e of the exhaust gas purifying catalyst 80 or a holding member 83 is formed on one end 1a side of a circumferential wall of the cylindrical body 1, the shoulder part 15 is contracted from a small diameter part to an opening of one end 1a, and a tip contracted cylindrical part 14 having an inclined wall part 14a inclined to the axis P1 of the cylindrical body 1 is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a case for accommodating an exhaust gas purifying catalyst.

[0002]

2. Description of the Related Art A housing case for housing an exhaust gas purifying catalyst has a central axis P as shown in FIG.
One end 100a and the other end 100c extending in the direction c are opened, and the inside is formed by a metal cylindrical body 100 which becomes a catalyst accommodating space 100d. In order to increase the purification performance of the exhaust gas purification catalyst, it is necessary to increase the diameter size and the shaft length size of the exhaust gas purification catalyst housed in the cylinder 100. Therefore, in this housing case, the diameter and the axial length of the catalyst housing space 100d for housing the exhaust gas purifying catalyst are set to be large.

Further, while increasing the diameter of the catalyst accommodating space 100d, the end of the accommodating case at the one end 100a or the other end 100c is outwardly moved toward the distal end opening in order to improve the mountability of the accommodating device such as a vehicle. A front-end contracted tube portion 110 having an inclined wall portion 110a having a smaller diameter and a front-end contracted tube portion 120 also having an inclined wall portion 120a are formed.

As shown in FIG. 11, which is a cross section of the conventional case, the housing case has a first cross section C formed by press forming and has a first flange portion 151.
A member 150 and a second member 160 having a flange portion 161 having a cross section C shape also formed by press forming are formed, and the flange portion 151 of the first member 150 and the second member 16 are formed.
The flange portion 161 is assembled in a state where the flange portion 161 is abutted with each other, and thereafter, is formed by a cylindrical welded product integrally joined by welding.

Japanese Patent Laid-Open No. 11-147138 (1)
In 999), a processing tool having a plurality of rolls arranged in a circumferential direction and a cylinder as a processing object were used, and the center axis of the cylinder and the revolving axis of the roll were relatively eccentric. A technique for performing spinning in this state is disclosed. According to this technique, the reduced diameter tube can be formed in a state where the center axis of the reduced diameter tube is eccentric with respect to the center axis of the cylindrical body.

Japanese Patent Application Laid-Open No. 11-151535 (1)
In 999), a processing tool in which a plurality of rolls are arranged in the circumferential direction and a cylindrical body as a processing object are used, and the center axis of the cylindrical body and the revolving axis of the roll are relatively inclined. A technique for performing spinning is disclosed. According to this technique, the reduced diameter tube can be formed in a state where the center axis of the reduced diameter tube is inclined with respect to the center axis of the cylindrical body.

[0007]

FIG. 10 and FIG. 1 described above.
In the case where the housing case is formed by welding as shown in FIG. 1, first, the first member 150 and the second member 160 are formed into a predetermined shape by press forming, and then the flange portion 15 is formed.
Each member 150, 160 in a state where
And the members 150 and 160 are joined by welding. In this case, the number of manufacturing steps increases and the cost increases. Moreover, the flange portions 151 and 161
Requires extra mounting space. Further, if the welding is not complete, there is a risk of exhaust gas leakage at the boundary between the members 150 and 160.

In recent years, as shown in FIG. 12, the present inventors have performed spinning molding on the peripheral wall of a cylindrical body 200 using a metal cylindrical body 200 having a straight cylindrical shape having the same diameter over the entire length. , The end of the cylindrical body 200
Therefore, a method for manufacturing a housing case for housing an exhaust gas purifying catalyst by forming the above is being developed. Tip contraction part 2
10 has an inclined wall portion 211 that is inclined so as to reduce the diameter toward the tip.

By forming the peripheral wall of the casing for accommodating the exhaust gas purifying catalyst by spinning as described above, the flange portion requiring an extra mounting space can be eliminated, and the welding step is eliminated or simplified. And the manufacturing cost can be reduced. Further, various effects can be obtained such that the risk of exhaust gas leakage at the boundary between the members 150 and 160 can be avoided.

By the way, when forming the inclined wall portion 211 constituting the distal contracted tube portion 210 by spinning, if the inclination angle θ6 of the inclined wall portion 211 of the distal contracted tube portion 210 with respect to the center axis Pc of the cylinder 200 is large. In other words, if the diameter reduction ratio of the inclined wall portion 211 of the distal end reduced cylinder portion 210 is high, depending on the material of the cylindrical body 200, the processing speed at the time of spinning molding, etc. Processing defects (processing defects) may occur.

Therefore, in order to suppress the above-described processing defects, the front-end contracted cylinder portion 21 with respect to the center axis Pc of the cylinder 200 is required.
It is effective to reduce the inclination angle θ6 of the 0 inclined wall portion 211, in other words, to adopt a measure to reduce the diameter reduction ratio of the inclined wall portion 211 of the distal end contraction tube portion 210.

However, when such a measure is adopted, the axial length La of the inclined wall portion 211 of the distal end contraction portion 210 becomes large, and as a result, the overall length Ld of the storage case becomes larger.
, And the mountability of the storage case in a partner device such as a vehicle is deteriorated.

Further, while maintaining the total length Ld of the storage case constant, the axial length L
When a is lengthened, processing defects such as wrinkles are reduced,
The axial length Le of the catalyst accommodating space 200d for accommodating the exhaust gas purifying catalyst is shortened, which leads to a reduction in the axial length of the exhaust gas purifying catalyst, which tends to reduce the purifying effect, which is not preferable.

Further, the above-mentioned Japanese Patent Application Laid-Open No. 11-147138
And Japanese Patent Application Laid-Open No. 11-151535, when applied to a case for accommodating an exhaust gas purifying catalyst,
The problem that the mountability of the storage case to the partner device such as a vehicle is reduced and the tendency of the purification effect of the exhaust gas purification catalyst to be reduced remain unchanged.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and it is possible to reduce the axial length of the inclined wall portion of the distal end reduced portion while securing the axial length of the exhaust gas purifying catalyst. It is an object of the present invention to provide a method of manufacturing a case for accommodating an exhaust gas purifying catalyst, which can suppress the occurrence of processing defects such as wrinkles on an inclined wall portion of the portion.

[0016]

According to a first aspect of the present invention, there is provided a method of manufacturing a casing for an exhaust gas purifying catalyst, comprising: a metal tube having one end and the other end extending in the center axis direction and having an inside serving as a catalyst housing space; Body, using a working tool for spinning molding pressed against the outer surface of the peripheral wall of the cylindrical body, an operation of rotating the working tool around a central axis of the cylindrical body, and applying the working tool to the cylindrical body The spinning molding is performed by the operation of moving toward the center of the cylindrical body, and along the direction perpendicular to the central axis of the cylindrical body, and the end of the exhaust gas purifying catalyst or the step facing the holding member holding the exhaust gas purifying catalyst. An inclined shoulder is formed on at least one end of a peripheral wall of the cylindrical body, and further, the diameter of the shoulder is reduced from the small diameter portion of the shoulder toward the opening, and the inclined body is inclined with respect to a central axis of the cylindrical body. Wall And forming a tip reduced cylindrical portion having.

According to a second aspect of the present invention, there is provided a method for manufacturing a casing for an exhaust gas purifying catalyst, comprising: a metal tubular body which is open at one end and the other end extending in the direction of the central axis and has a catalyst containing space inside; Using a processing tool for spinning molding pressed against the outer surface of the peripheral wall, rotating the processing tool around a central axis of the cylinder, and moving the processing tool toward the cylinder. By performing spinning molding, along a direction perpendicular to the axis of the center axis of the cylindrical body, the end of the exhaust gas purification catalyst or the stepped shoulder facing the holding member that holds the exhaust gas purification catalyst,
Formed on at least one end side of the peripheral wall of the cylindrical body, and further formed an intermediate reduced cylindrical portion having a wall portion extending from the small diameter portion of the shoulder toward the opening, and thereafter, The central axis of the cylindrical body is inclined with respect to the main axis, and in this state, the intermediate reduced cylinder portion is subjected to spinning with the processing tool, and the central axis of the cylindrical body before the shoulder portion is formed. It is characterized in that a tip-end contracted tube portion having a slanted central axis line and having a slanted wall portion whose diameter is reduced toward the opening is formed.

According to a third aspect of the present invention, there is provided a method of manufacturing a casing for an exhaust gas purifying catalyst, comprising: a metal tubular body which is open at one end and the other end extending in the direction of a central axis and has a catalyst containing space inside; Using a processing tool for spinning molding pressed against the outer surface of the peripheral wall, rotating the processing tool around a central axis of the cylinder, and moving the processing tool toward the cylinder. By performing spinning molding, along a direction perpendicular to the axis of the center axis of the cylindrical body, the end of the exhaust gas purification catalyst or the stepped shoulder facing the holding member that holds the exhaust gas purification catalyst,
Formed on at least one end side of the peripheral wall of the cylindrical body, and further formed an intermediate reduced cylindrical portion having a wall portion extending from the small diameter portion of the shoulder toward the opening, and thereafter, The center axis of the cylinder is eccentric and inclined with respect to the main axis, and in this state, the intermediate reduced cylinder portion is subjected to spinning with the machining tool, and the center of the cylinder before forming the shoulder portion It is characterized in that the distal end contracted tube portion having a central axis line inclined and eccentric with respect to the axis and having an inclined wall portion reduced in diameter toward the opening is formed.

According to the method for manufacturing the case for accommodating the exhaust gas purifying catalyst according to the first to third aspects of the present invention, the stepped shoulder portion is formed along the direction perpendicular to the central axis of the cylindrical body. When the shoulder portion is formed along the direction perpendicular to the axis as described above, the diameter reduction start point of the distal end contraction portion shifts radially inward in the direction perpendicular to the axis. For this reason, even when the axial length of the inclined wall portion of the distal end contraction portion is suppressed, the inclination angle of the inclined wall portion of the distal end contraction portion with respect to the center axis of the cylinder becomes small. In other words, the diameter reduction ratio of the inclined wall portion of the distal end reduced cylinder portion is reduced, and processing defects such as wrinkles are reduced.

When the exhaust gas purifying catalyst is accommodated in the accommodating case, the stepped shoulder faces the end of the exhaust gas purifying catalyst or the holding member that holds the exhaust gas purifying catalyst.
Therefore, the shoulder is preferably reinforced. According to the method for manufacturing an exhaust gas purifying catalyst housing case according to the present invention, as described above, the stepped shoulder extends along the direction perpendicular to the central axis of the cylindrical body. High degree of processing when spinning. Therefore, the ratio of the work hardening is high in the shoulder portion, and the hardness is increased and strengthened by the work hardening.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for manufacturing a case for accommodating an exhaust gas purifying catalyst according to the present invention will be described with reference to an embodiment shown in FIG. As shown in FIG. 9, by the spinning molding, a stepped shoulder portion 15 is formed on one end 1 a side of the cylindrical body 1 along a direction perpendicular to the central axis P <b> 1 of the cylindrical body 1.
Is formed. When the shoulder portion 15 is formed along the direction perpendicular to the axis in this manner, the diameter reduction start point M of the inclined wall portion 14a of the distal reduced tube portion 14 is smaller than that in the case where the shoulder portion 15 is not formed. It moves radially inward in the direction perpendicular to the axis of the body 1.

As described above, in order to keep the purification performance of the exhaust gas purifying catalyst housed in the housing case high, it is necessary to make the axial length L2 of the exhaust gas purifying catalyst as long as possible. In addition, in the housing case for housing the catalyst, it is necessary to minimize the axial length L1 of the housing case for reasons such as reducing the size and improving the mountability. Therefore, it is necessary to set the axial length L3 of the inclined wall portion 14a of the distal end contracted tube portion 14 so as not to be as long as possible.

Even in such a case, if the shoulder portion 15 is formed along the direction perpendicular to the axis, and if the distal end contraction tube portion 14 extends from the small diameter portion of the shoulder portion 15, the shoulder portion 15 Is not formed, the inclination angle θ1 of the inclined wall portion 14a of the distal end contraction tube portion 14 with respect to the central axis P1 of the cylindrical body 1 can be reduced. In other words, it is possible to reduce the diameter reduction ratio of the inclined wall portion 14a of the diameter-reduced leading end reduced tube portion 14.

As a result, when spinning the inclined wall portion 14a, it is possible to suppress the occurrence of processing defects such as wrinkles on the inclined wall portion 14a of the distal end contraction tube portion 14. Further, since it is possible to suppress a sudden change in the flow path area through which the exhaust gas flows, the flow of the exhaust gas can be smoothed.

In FIG. 9, the contour of the inclined wall portion 14 a of the distal end contraction tube portion 14 when the shoulder portion 15 is not formed is indicated by a virtual line R. In this case, the inclination angle θ2 of the inclined wall portion 14a of the distal end contraction tube portion 14 with respect to the center axis P1 of the cylindrical body 1 is equal to the angle θ1.
(Θ2> θ1). When the inclination angle θ2 is large, the rate of change in the degree of processing increases during spinning molding, so that processing defects such as wrinkles are likely to occur when the inclined wall portion 14a is formed by spinning molding, and the exhaust gas is smoothed. It is difficult to secure a proper flow.

Although it depends on the material of the cylinder 1, the processing conditions, the flow state of the exhaust gas, the required exhaust gas purification capacity, the cost, etc., when the outer diameter of the cylinder 1 is 100,
As shown in FIG. 9, when the size of one side of the shoulder portion 15 formed on both sides in the radial direction is K2, if K2 is exemplified, K2 is, for example, 2 to 20, 3 to 15, especially 4 to 1.
Can be zero. However, it is not limited to this.

According to the method for manufacturing a case for accommodating an exhaust gas purifying catalyst according to the present invention, for example, the following mode can be adopted.

(1) After forming the shoulder portion, in forming the front end contraction tube portion, an eccentric operation of moving the cylinder with respect to the processing tool along a direction perpendicular to the central axis of the cylinder is performed. It is possible to adopt a form in which the center axis of the tip contraction tube portion is eccentric with respect to the center axis of the tube body before forming the shoulder portion. By performing the eccentric operation, it is possible to form a front-end contracted tube portion having a wall portion that is eccentric with respect to the center axis of the cylinder body before forming the shoulder portion.

(2) After forming the shoulder portion, in forming the front end contraction tube portion, an embodiment is employed in which the cylinder is tilted with respect to the center axis of the cylinder before the shoulder portion is formed. can do. By performing the tilting operation, it is possible to form a front-end contracted cylindrical portion having a central axis inclined with respect to the central axis of the cylindrical body before forming the shoulder portion.

Both the eccentric operation and the tilt operation described above can be performed together. By performing both the eccentric operation and the tilting operation, it is possible to form a front-end contracted cylinder portion having an eccentric and inclined central axis with respect to the central axis of the cylindrical body before forming the shoulder portion.

(3) The reduced-end cylindrical portion has an inclined wall portion which is reduced in diameter from the small-diameter portion of the shoulder toward the opening and which is inclined with respect to the center axis of the cylindrical body, and a small-diameter portion of the inclined wall portion. And a wall extending along the central axis of the cylindrical body and extending toward the opening. In this case, since a wall portion is formed along the central axis of the cylindrical body from the small diameter portion of the inclined wall portion toward the opening, the straight pipe portion at the tip of the exhaust pipe to be connected is provided in the housing case. It becomes easy to fit and connect.
Further, the distal end contracted tube portion may be configured such that the whole is inclined and reduced in diameter toward the opening.

(4) After forming the front-end contracted cylinder portion as described above, the other end of the cylindrical body such that the end of the exhaust gas purification catalyst or the holding member holding the exhaust gas purification catalyst faces the shoulder. An exhaust gas purification catalyst is accommodated in the catalyst accommodation space from the opening. Thereafter, by spinning the processing tool around the central axis of the cylinder and by moving the processing tool toward the cylinder, spinning is performed on the peripheral wall on the other end side of the cylinder,
The second end reduced tube portion can be formed by reducing the diameter of the peripheral wall on the other end side of the cylindrical body. In this case, in order to form both the one end side and the other end side of the cylindrical body by spinning, a distal end reduced cylindrical part is formed at one end side of the cylindrical body, and a second distal end reduced cylindrical part is formed at the other end side of the cylindrical body. Can be formed.

(5) An embodiment in which the cylinder is made of an iron-based, for example, ferrite-based or austenitic-based stainless steel as a base material can be adopted. A ferritic or austenitic stainless steel can ensure plastic deformation of the cylindrical body during spinning and heat resistance during use. In addition, in the case of austenitic stainless steel, in addition to strengthening by work hardening, martensitic formation by work-induced transformation and, consequently, martensitic strengthening can be expected. In some cases, the material of the cylindrical body may be a carbon steel type, another alloy steel type, an aluminum alloy, a titanium alloy, or any material that can be spin-formed.

(6) As the exhaust gas purifying catalyst held in the housing case, a carrier having a large number of pore passages made of a metal or a ceramic is used as a catalyst substance (for example, at least one of platinum, rhodium and para-radium). ) Can be employed. The exhaust gas purifying catalyst is generally mounted on a vehicle, but may be mounted on industrial equipment that generates exhaust gas.

(7) If necessary, spinning can be performed with a cylindrical mandrel arranged inside the cylindrical body.

(8) The size of the cylindrical body can be appropriately selected according to the application, and the outer diameter is 40 to 300 mm.
In particular, 70 to 150 mm, the plate thickness is 0.5 to 5 mm,
In particular, it can be 1.5 to 2 mm, but is not limited to this.

[0037]

(Embodiment 1) A first embodiment of the present invention will be described below with reference to the drawings.

First, the spinning molding device 5 used in the present embodiment will be described with reference to FIGS. The spinning molding apparatus 5 includes a base table 50 extending in a horizontal direction, and a moving table 53 having a slider 52 movably provided in the directions of arrows Y1 and Y2 along a rail portion 51 of the base 50.
A rotary table 54 rotatably provided around a vertical axis Pm on a moving table 53 for tilting operation to be described later, and a positioning device mounted on the rotary table 54 for positioning the cylindrical body 1 which is an object to be processed. Device 55 and a chuck device 57 having a pair of upper and lower chuck means 56 which are mounted on the rotary table 54 and hold the cylindrical body 1 which is a processing object.
And a chuck cylinder 58 for lifting and lowering the upper chuck means 56 to release and chuck the chuck, and a parallel movement for moving the moving table 53 together with the chuck device 57 in the directions of arrows Y1 and Y2 to perform an eccentric operation described later. And a motor 59.

Further, as shown in FIG. 2, the spinning molding device 5 includes a slider which is held on a rail portion 60 of a base 50 so as to be movable in the directions of arrows X1 and X2 (directions orthogonal to the directions of arrows Y1 and Y2). A headstock 62 having a head 61;
2 and a main shaft moving motor 6 for moving the main shaft 63 in the directions of arrows X1 and X2.
4, a machining tool 66 mounted at the tip of the main shaft portion 63 so as to be movable in the radial direction, that is, along the directions of arrows D1 and D2, and by rotating the main shaft portion 63 around its main axis P5. A drive motor 68 for revolving and rotating the processing tool 66 is provided. The processing tools 66 are formed of a material having high wear resistance, and a plurality (for example, a total of three) of the processing tools 66 are arranged at equal intervals around its own revolution axis.
Note that the number of working tools 66 can be increased or decreased as necessary.

As shown in FIG. 3A, the cylindrical body 1 which is the object to be machined before the spinning used in this embodiment.
Is made of metal having one end 1a and the other end 1c extending in the direction of the center axis P1 and having an inside serving as a catalyst housing space 1d, and has a center axis P1.

The cylindrical body 1 before spinning is formed by cutting a long metal cylinder in series, has a straight cylindrical shape, and is set so that the thickness and the outer diameter are almost the same over the entire length. I have. The material of the cylinder 1 can be iron-based, for example, ferrite-based or austenitic-based stainless steel.

First, in performing spinning molding, FIG.
As shown in (A), the cylindrical body 1 is a horizontal axis type, and the outer peripheral portion 1w of the cylindrical body 1 is sandwiched and fixed by a pair of chuck means 56. At this time, the center axis P1 of the cylindrical body 1 and the main axis P5 of the main shaft portion 63 (that is, the revolution axis of the machining tool 66) are made to coincide.

In this state, each machining tool 6 shown in FIG.
6 is rotated around the main axis P5, that is, the center axis P1 of the cylindrical body 1 at a predetermined rotational speed. Even if the processing tool 66 rotates and revolves, the cylindrical body 1 as a processing object is fixed and does not rotate.

Then, in order to perform the spinning molding, the working tool 66 is moved along the direction perpendicular to the axis of the cylinder 1, that is, the arrow D1.
An operation is performed to push the working tool 66 toward the peripheral wall of the cylindrical body 1 by pushing the working tool 66 in the direction at a predetermined speed. As a result, the plurality of processing tools 66 gradually decrease in orbital radius, and FIG.
(A) Outer peripheral portion 1 on one end 1a side of peripheral wall of cylindrical body 1
w to perform spinning molding. As a result,
As shown in FIG. 3B, a stepped shoulder portion 15 is formed on one end 1 a side of the peripheral wall of the cylindrical body 1. The shoulder 15 has a ring shape coaxial with the center axis P1 of the cylinder 1 and extends in a direction perpendicular to the center axis P1 of the cylinder 1.

Since the shoulder 15 has a large outer diameter change rate, when forming the shoulder 15, it is necessary to increase the pushing amount of the working tool 66. As shown in FIG. 4 described later, the shoulder portion 15 is an end portion 80e of the exhaust gas purification catalyst 80 or a portion facing the holding member 83 that holds the exhaust gas purification catalyst 80.

Further, in this embodiment, as shown in FIG. 3B, the reciprocating movement of the working tool 66 from the pressing start area Hs to the pressing end area Hf is repeated a plurality of times, and the cylinder 1
A first intermediate reduced cylinder portion 11 is formed on one end 1a side of the first intermediate compressed cylinder portion 11. The first intermediate reduced cylinder portion 11 has a straight cylindrical shape narrower than the diameter of the cylindrical body 1 before processing, and has substantially the same outer diameter over its axial length. The central axis of the first intermediate cylinder portion 11 is P1
And the central axis of the unreduced diameter portion of the cylindrical body 1 is also P1,
These correspond to the main axis P5 of the main shaft portion 63. After forming the first intermediate reduced cylinder portion 11 as described above, the processing tool 66 is moved in the direction of arrow D2 to expand and retract.

Next, as shown in FIG. 3 (C), while the cylinder 1 held by the chuck means 56 is being chucked, the cylinder 1 is moved together with the chuck means 56 to the main axis P5 of the main shaft portion 63. , An eccentric operation of performing parallel movement along the direction of arrow Y1 is performed. In this state, while rotating and revolving the processing tool 66, the processing tool 66 is pushed in the radial direction, that is, the direction of the arrow D <b> 1, and the first intermediate reduced cylinder portion 11 is pressed.
And spinning is performed. Thereby, the second intermediate reduced cylinder portion 12 is formed on one end 1a side of the cylindrical body 1.
After the second intermediate reduced cylinder portion 12 is formed in this way, the processing tool 66 is moved to expand in the direction of arrow D2, and the second intermediate reduced cylinder portion 1 is moved.
Evacuate from 2.

The second intermediate reduced cylinder portion 12 has an intermediate inclined wall portion 1 which is gradually reduced in diameter toward one end 1a and is inclined.
2a and an intermediate neck portion 12c extending in a straight cylindrical shape from a small diameter portion of the intermediate inclined wall portion 12a. Middle neck 1
The center axis P2 of 2c corresponds to the main axis P5 of the main shaft portion 63 and the center axis P1 of the unreduced diameter portion of the cylinder 1 (corresponding to the center axis P1 of the cylinder 1 before forming the shoulder 15). It is eccentric with respect to. The diameter of the neck 12c is substantially the same over its axial length.

As described above, in order to move the cylindrical body 1 in parallel with ΔY, the parallel movement motor 59 shown in FIG.
Is translated. In some cases, the positioning device 55 may be used. Although ΔY can be selected as appropriate, the cylinder 1
Is preferably set to be equal to or less than the radius of

Next, as shown in FIG. 3 (D), with the cylindrical body 1 held by the chuck means 56 still being chucked, together with the chuck means 56, the central axis of the unreduced diameter portion of the cylindrical body 1 P1 is the angle θ with respect to the main axis P5 of the main shaft 63.
Perform a tilt operation to tilt.

That is, the cylinder 1 is inclined with respect to the central axis P1 of the cylinder 1 before the shoulder 15 is formed. The angle θ can be appropriately selected, and can be set to any one of, for example, 3 to 45 degrees.

In the state where the tilting operation is performed as described above, the plurality of processing tools 66 are pushed in the radial direction, that is, the direction of arrow D1 while rotating and revolving the processing tools 66 in the same manner as described above, and the second intermediate reduced cylinder portion is formed. The spinning molding is performed by pressing against the peripheral wall of No. 12. As a result, the center axis P of the unreduced diameter portion of the cylinder 1
A front-end contracted tube portion 14 having a center axis inclined with respect to 1 is formed on one end 1a side of the tube 1.

After forming the distal end contraction portion 14 in this manner,
The processing tool 66 is detached from the front end reduced tube portion 14. Thereby, a storage case is formed.

As shown in FIG. 3D, the distal end contracted tube portion 14
Is provided with an inclined wall portion 14a that is inclined while reducing its diameter toward the one end 1a, and a neck portion 14c that extends in a straight cylindrical shape from a small diameter portion of the inclined wall portion 14a. Neck 14c
Are set so that their diameters are substantially the same over their axial length.

In this embodiment, in order to incline the cylinder 1 at the angle θ as described above, the rotary table 54 shown in FIG.
Is rotated about the vertical axis Pm. In the present embodiment, as shown in FIG. 3D, no spinning molding is performed on the other end 1c side of the cylindrical body 1.

When spinning is completed by performing the above-described operation, the cylinder 1 is detached from the chuck means 56. Thereafter, as shown in FIG. 4, a monolithic exhaust gas purifying catalyst 80 is inserted into and accommodated in the catalyst accommodating space 1d of the cylindrical body 1 serving as an accommodating case. In this state, the ring-shaped holding member 83 is housed between the peripheral wall of the cylindrical body 1 serving as the housing case and the exhaust gas purifying catalyst 80, and the holding ability of the exhaust gas purifying catalyst 80 is enhanced.

The holding member 83 generally has a function of alleviating impact on the exhaust gas purifying catalyst 80,
It is formed of a heat-resistant aggregate of fibers or wires or a porous body having a group of pores so that a dimensional tolerance function or the like can be exhibited. Ceramic fibers, metal wires, and the like can be used as the heat-resistant fibers or wires. As the porous body, a foam, particularly a foam having heat resistance can be used.

When the exhaust gas purifying catalyst 80 is housed in the housing case in this way, as shown in FIG.
Faces the end 80e of the outer box 80b of the exhaust gas purifying catalyst 80 and the holding member 83. Thereby, the holding ability of holding the exhaust gas purifying catalyst 80 is enhanced. The exhaust gas purifying catalyst 80 includes a catalyst main body 80a having an exhaust gas purifying function, and an outer box 80b surrounding the catalyst main body 80a from outside.

The catalyst body 80a includes a carrier having a support layer such as an alumina layer forming a pore passage, and a catalyst supported on the support layer. Since the shoulder portion 15 is bent along a direction perpendicular to the axis, the shoulder portion 15 is unlikely to be an original passage for exhaust gas. Further, the outer box 80b of the exhaust gas purifying catalyst 80 itself does not carry a catalytic metal. Therefore, even if the shoulder portion 15 facing the end portion 80e of the outer box 80b is formed, the influence on the exhaust gas purification performance can be avoided.

Thereafter, as shown in FIG. 4, a lid member 19 is welded to the other end 1c of the cylindrical body 1. When the storage case is mounted on a vehicle, the lid member 19 is connected to the internal combustion engine side, and the distal end contracted tube portion 14 is connected to the muffler side. Therefore, the exhaust gas discharged from the internal combustion engine flows in the order of the lid member 19, the exhaust gas purifying catalyst 80, and the front end reduced cylinder portion 14. When the exhaust gas passes through the fine flow passage of the exhaust gas purification catalyst 80, the exhaust gas is purified.

Note that, due to the mounting space in the vehicle, the axial length L1 of the storage case (see FIG. 4) is set so as not to become excessively large as described above.
In order to maintain the catalytic performance of the exhaust gas purifying catalyst 80 high, the axial length L2 of the exhaust gas purifying catalyst 80 is considerably required, and is set so as not to be excessively short. Therefore, the inclined wall portion 1 of the distal end contraction tube portion 14 of the storage case 1
The length of the shaft length dimension L3 of 4a cannot be too long.

The imaginary line Rs in FIG. 4 shows the contour of the front end contracted tube portion 14 when the shoulder portion 15 is not formed. Shoulder 15
Is not formed, as compared with the case where the shoulder portion 15 is formed, the reduced-diameter start end of the inclined wall portion 14a shifts radially outward, so that the center of the unreduced-diameter portion of the cylindrical body 1 is shifted. Axis P1
Angle θ3 of the inclined wall portion 14a of the tip contraction tube portion 14 with respect to
_{0, θ4 0} increases.

In this respect, in this embodiment, a stepped shoulder portion 15 is formed along the axis perpendicular to the central axis P1 of the unreduced diameter portion of the cylindrical body 1, and the tip of the reduced-tube portion 14 is inclined. it can be shifted to the radially inward side in the condensation-diameter starting M _O of the tubular body 1 the axis-perpendicular direction of the wall portion 14a. Therefore, as can be understood from FIG. 4, the inclination angles θ3 and θ4 of the inclined wall portion 14a of the distal end contraction tube portion 14 with respect to the center axis P1 of the cylinder 1 can be reduced.

[0064] Judging from the drawing of Figure 4 according to the present embodiment, the inclination angle .theta.3 inclined surface 14a of the case of forming the shoulder portion 15 is about 30 inclination angle .theta.3 ₀ in the case of not forming the shoulder 15 It was 40%, the inclination angle .theta.4 inclined surface 14a of the case of forming the shoulder portion 15 is about 60% to 70% of the inclination angle .theta.4 ₀ in the case of not forming the shoulder 15.

As described above, the inclination angle θ3 of the inclined wall portion 14a,
When θ4 is reduced, the diameter reduction ratio of the inclined wall portion 14a can be reduced. Therefore, the inclined wall portion 1 of the tip contraction tube portion 14
When spinning 4a, generation of processing defects such as wrinkles can be suppressed.

The storage case manufactured in this embodiment is suitable for a type in which the length of the axial length L3 of the inclined wall portion 14a of the distal end contraction tube portion 14 is limited to a small size because of the mounting space in the vehicle.

As described above, in this embodiment, since the inclination angles θ3 and θ4 of the inclined wall portion 14a of the distal end contraction portion 14 with respect to the center axis P1 of the cylindrical body 1 can be reduced, exhaust gas flows. In the direction, the reduction rate of the flow path area formed by the inclined wall portion 14a of the distal end contraction portion 14 can be reduced as much as possible, which can contribute to smooth flow of exhaust gas.

Further, in the present embodiment, the peripheral wall of the front-end contracted tube portion 14 subjected to spinning, that is, the inclined wall portion 14a
Further, since the neck portion 14c is strengthened by work hardening, the neck portion 14c is not easily deformed even when an unexpected external force acts.

As described above, when the exhaust gas purifying catalyst 80 is accommodated in the accommodating case, as shown in FIG. 4, the stepped shoulder portion 15 is connected to the end 80e of the outer box 80b of the exhaust gas purifying catalyst 80. Alternatively, the holding member 83 that holds the exhaust gas purification catalyst 80 faces. For this reason, the exhaust gas purifying catalyst 80
It is preferable that the vicinity of the shoulder portion 15 is reinforced in order to increase the holding ability of the head. In this respect, in the present embodiment, the shoulder portion 15 is reinforced by work hardening as in the case of the distal end contracted tube portion 14 (that is, the inclined wall portion 14a and the neck portion 14c), and the holding capacity of the exhaust gas purification catalyst 80 can be increased. it can.

According to the test conducted by the present inventors, the cylindrical body 1
If the material is ferritic stainless steel,
The hardness of the portion not subjected to spinning is generally about 150 to 170 in Vickers hardness, but the portion subjected to spinning such as in the vicinity of the shoulder portion 15 is generally 210 to 170 in Vickers hardness. The hardness was increased to about 250, and it was strengthened.

If the material of the cylindrical body 1 is austenitic stainless steel, not only strengthening by work hardening,
Strengthening accompanying martensitic transformation by processing-induced transformation can also be achieved, and the ability to hold the exhaust gas purification catalyst 80 can be enhanced.

(Embodiment 2) Embodiment 2 is performed under basically the same conditions as Embodiment 1. Therefore, the second embodiment has the same operation and effect as the first embodiment. Hereinafter, the different parts will be mainly described.

In the first embodiment, as described above, the eccentric operation is performed, the spinning molding is performed on the cylindrical body 1 in which the eccentric operation has been performed, and then the tilt operation is performed. Spinning molding is performed on the cylindrical body 1 to form the front-end contracted cylindrical portion 14.

In the second embodiment, as shown in FIGS. 5 (A) to 5 (C), the cylinder 1 having the shoulder portion 15 and the first intermediate reduced cylinder portion 11 is moved with respect to the main axis P5 of the main shaft portion 63. The eccentric operation and the tilting operation are performed together, and the first intermediate reduced cylinder portion 1 of the cylindrical body 1 is formed.
The spinning molding is performed on the peripheral wall of the first workpiece by the processing tool 66.

That is, as shown in FIG. 5 (A), the cylindrical body 1 is a horizontal axis type, and the outer peripheral portion 1w of the cylindrical body 1 is
6 and fix it. At this time, the center axis P1 of the cylinder 1
And the main axis P5 of the main spindle 63 (the revolving axis of the machining tool 66). In this state, as shown in FIG. 5B, an operation of revolving the processing tool 66 around the central axis P1 of the cylindrical body 1 at a predetermined rotation speed is performed. The cylindrical body 1, which is a processing object, is fixed and does not rotate.

Then, in order to perform spinning, the working tool 66 is moved along the direction perpendicular to the central axis P1 of the cylindrical body 1, that is, in the direction of arrow D1, and the working tool 66 is moved toward the peripheral wall of the cylindrical body 1. Perform the operation. As a result, the processing tool 66 is pressed against the outer surface on the one end 1a side of the peripheral wall of the cylindrical body 1 to perform spinning forming, and the stepped shoulder portion 15 is formed on one end 1a side of the peripheral wall of the cylindrical body 1. The shoulder 15 extends in a direction perpendicular to the axis with respect to the central axis P1 of the cylinder 1.

Next, as can be understood from FIG.
With respect to the main axis P5 of the main shaft portion 63, an eccentric operation for moving the central axis P1 of the non-reduced diameter portion of the cylindrical body 1 in parallel is performed, and an inclination operation for tilting the angle θ is performed.

In this state, while the processing tool 66 is rotated and revolved, the processing tool 66 is pressed against the peripheral wall of the second intermediate reduced cylinder portion 12 to perform spinning molding. As a result, the tip reduced cylinder portion 14 having a center axis eccentric and inclined with respect to the center axis P1 of the unreduced diameter portion of the cylinder 1 is formed. Thereby, a storage case is formed. In this embodiment, the other end 1c of the cylindrical body 1 is not subjected to spinning.

When the spinning molding is completed, the cylinder 1 is detached from the chuck means 56. After that, similarly to the first embodiment, the exhaust gas purifying catalyst 80 of the monolith type is pushed into the storage case and stored. Then, as in the first embodiment,
The lid member 19 is joined to the other end 1c side of the cylindrical body 1 by welding.

(Embodiment 3) Hereinafter, Embodiment 3 will be described with reference to FIG.
A description will be given with reference to (A), (B), and (C). The third embodiment has basically the same configuration as the first embodiment, and therefore has basically the same operation and effect. Hereinafter, a description will be given focusing on a portion different from the first embodiment.

In the third embodiment, the eccentric operation and the tilting operation are performed in the same procedure as in the first embodiment, and the front-end contracted tube portion 14 having the inclined wall portion 14a as shown in FIG. 1 is formed on one end 1a side.

Next, the cylinder 1 is detached from the chuck means 56, and the exhaust gas purifying catalyst 80 is accommodated in the catalyst accommodation space 1d from the opening on the other end 1c side of the cylinder 1 as shown in FIG. I do. When the exhaust gas purifying catalyst 80 is housed in the catalyst housing space 1d in this way, the opening on the other end 1c side of the cylindrical body 1 is set to the upper side, and the opening on the one end 1a side is set to the lower side. The exhaust gas purifying catalyst 80 is housed together with the holding member 83.

In the state where the exhaust gas purifying catalyst 80 is accommodated in the catalyst accommodating space 1d in this manner, the end portion 80e or the holding member 83 of the exhaust gas purifying catalyst 80 faces the shoulder 15 as in the first embodiment. As a result, the ability to hold the exhaust gas purifying catalyst 80 is improved.

Next, as shown in FIG. 6C, the cylinder 1 is again held by the chuck means 56, and the machining tool 66 is moved to the cylinder 1 again.
And the operation of moving the processing tool 66 along the direction perpendicular to the axis of the cylindrical body 1, whereby spinning is performed on the peripheral wall on the other end 1 c side of the cylindrical body 1. As a result, the diameter of the peripheral wall on the other end 1c side of the cylindrical body 1 is reduced, and the shoulder 15
While forming the ring-shaped second shoulder 17 similar to the above,
A second distal end contracted tube portion 18 extending from the small diameter portion of the second shoulder portion 17 is formed.

In the third embodiment, the shoulder 15 and the second shoulder 17 face the end portion 80e of the exhaust gas purifying catalyst 80 or the holding member 83, so that the holding performance of the exhaust gas purifying catalyst 80 is improved. ing.

In the third embodiment, the front end contracted tube portion 14 is formed on one end 1a side of the cylinder 1 by spinning, and the other end 1c of the cylinder 1 is formed on the other end 1c side by spinning. Since the two front end contracted tube portions 18 are formed, both the front end contracted tube portion 14 and the second front end contracted tube portion 18 can be strengthened by work hardening. That is, the housing case of the present embodiment has both ends in the axial direction reinforced. Therefore, even if an unexpected external force acts, it is difficult to deform. Of course, the shoulder 15 and the second shoulder 17 are also reinforced by work hardening.

In the third embodiment, the second tip contracted tube portion 18
Is formed, the central axis P of the non-reduced diameter portion of the cylindrical body 1 is formed.
1 or may be formed eccentrically with respect to the center axis P1 of the unreduced diameter portion of the cylindrical body 1, or the cylindrical body 1 It may be formed eccentric and inclined with respect to the center axis P1 of the reduced diameter portion.

The second distal end contraction portion 18 is provided with an inclined wall portion 18a having a gentle inclination with respect to the center axis P1 of the cylinder 1, but the present invention is not limited to this. The outer diameter may be substantially the same over the axial length of the cylindrical portion 18.

(Embodiment 4) Hereinafter, Embodiment 4 will be described with reference to FIG.
A description will be given with reference to (A), (B), and (C). The fourth embodiment has basically the same configuration as the first embodiment, and therefore has basically the same operation and effect. Hereinafter, a description will be given focusing on a portion different from the first embodiment.

In the fourth embodiment, the first step is performed first. In the first step, as in the first embodiment, a straight cylindrical body 1 shown in FIG. 7A having a uniform diameter over the axial length is used. Then, as shown in FIG. 7B, the shoulder 15 is formed in a ring shape on the peripheral wall of the cylindrical body 1 by spinning. Further, in the first step, the intermediate contracted tube portion 24 is formed coaxially with the tube 1 by spinning. Intermediate cylinder 2
4 has an intermediate inclined wall portion 24a which is inclined while reducing its diameter toward the one end 1a, and an intermediate neck portion 24c extending from a small diameter portion of the intermediate inclined wall portion 24a. Middle neck 24
c is set so that the diameter is substantially the same over its axial length. The intermediate constricted tube portion 24 formed in the first step,
That is, the intermediate inclined wall portion 24a and the intermediate neck portion 24c are concentric with the unreduced diameter portion of the cylindrical body 1.

Next, the second step (inclination operation) is performed. That is, in the second step, the rotary table 54 of the spinning molding device 5 on which the cylindrical body 1 is mounted is rotated by a predetermined angle about the vertical axis Pm while the cylindrical body 1 is kept chucked by the pair of chucking means 56. Thereby, the center axis P1 of the unreduced diameter portion of the cylindrical body 1 is inclined with respect to the main axis P5 of the main shaft portion 63 of the machining tool 66. With the center axis P1 of the non-reduced diameter portion of the cylindrical body 1 inclined with respect to the main axis P5 of the main shaft portion 63, the processing tool 66 is pushed in the radial direction, that is, the direction of arrow D1 while rotating and revolving. , Middle cylinder part 2
4 is subjected to spinning. As a result, FIG.
As shown in (B), the central axis P of the unreduced diameter portion of the cylindrical body 1
A front-end contracted tube portion 14 having a center axis inclined with respect to 1 is formed on one end 1a side of the tube 1.

The tip-end contracted tube portion 14 has an inclined wall portion 14a which is inclined while decreasing in diameter toward the one end 1a, and an inclined wall portion 1 which is inclined.
4a and a neck portion 14c extending from the small diameter portion.
The neck portion 14c is set so that its diameter is substantially the same over its axial length. In the fourth embodiment, the above-described eccentric operation is not performed.

(Embodiment 5) Hereinafter, Embodiment 5 will be described with reference to FIG.
A description will be given with reference to (A), (B), (C), and (D). The fifth embodiment has basically the same configuration as the fourth embodiment, and therefore has basically the same operation and effect. Hereinafter, a description will be given focusing on portions different from the fourth embodiment.

The first step of the fifth embodiment is basically the same as the first step of the fourth embodiment. That is, in the first step,
A cylindrical body 1 of a straight cylindrical shape shown in FIG. Then, as shown in FIG. 8B, the shoulder 15 is formed in a ring shape on the peripheral wall on the one end 1a side of the cylindrical body 1 by spinning. Further, in the first step, the intermediate reduced cylinder portion 34 is formed coaxially on one end 1a side of the cylindrical body 1 by spinning. The intermediate reduced tube portion 34 includes an intermediate inclined wall portion 34a that is inclined while reducing its diameter toward one end 1a,
An intermediate neck portion 34c extending from the small-diameter portion of the intermediate inclined wall portion 34a. The intermediate neck portion 34c is set so that its diameter is substantially the same over its axial length. The intermediate contracted tube portion 34 is concentric with the unreduced diameter portion of the tube 1.

Next, in this embodiment, the second step (inclination operation) and the third step (eccentric operation) are executed together. That is, while the cylinder 1 having the intermediate reduced cylinder portion 34 is being chucked by the pair of chucking means 56, the rotary table 54 of the spinning molding device 5 is rotated around the vertical axis Pm, and the cylinder 1 is rotated. A second step (inclination operation) of inclining the central axis P1 of the unreduced diameter portion with respect to the main axis P5 of the main shaft portion 63 is executed. At the same time, a third step (eccentric operation) of moving the moving table 53 of the spinning molding device 5 to move the central axis P1 of the unreduced diameter portion of the cylindrical body 1 in parallel to perform eccentricity is executed. In the state where the second step (eccentric operation) and the third step (eccentric operation) are performed in this manner, spinning is performed on the intermediate reduced cylinder portion 34 of the cylindrical body 1.

As a result, as shown in FIG. 8 (C), the front-end contracted tube portion 14 having a center axis eccentric and inclined with respect to the center axis P1 of the unreduced diameter portion of the tube body 1 One end 1a
Form on the side. The distal end contracted tube portion 14 has an inclined wall portion 14a which is inclined while reducing its diameter toward one end 1a, and a neck portion 14c extending from a small diameter portion of the inclined wall portion 14a. The diameter of the neck portion 14c is substantially the same over its axial length.

Next, the cylindrical body 1 having the front end reduced cylinder portion 14 formed at one end 1a is detached from the chuck means 56, and the exhaust gas purifying catalyst 80 is inserted into the catalyst accommodating space 1d from the opening at the other end 1c side of the cylindrical body 1. To accommodate. When the exhaust gas purifying catalyst 80 is accommodated in the catalyst accommodating space 1d in this manner, the opening on the other end 1c side of the cylindrical body 1 is set to the upper side, and the opening on the one end 1a side is set to the lower side, although not particularly shown. Then, the exhaust gas purifying catalyst 80 is housed in the catalyst housing space 1d together with the holding member 83.

In the state where the exhaust gas purifying catalyst 80 is accommodated in the catalyst accommodating space 1d, the exhaust gas purifying catalyst 80
Alternatively, since the holding member 83 faces the shoulder portion 15, the holding ability for the exhaust gas purification catalyst 80 is enhanced.

Next, as shown in FIG. 8D, the cylinder 1 containing the exhaust gas purifying catalyst 80 is held upside down again on the pair of chuck means 56, and the processing tool 66 is
And an operation of moving the processing tool 66 toward the cylindrical body 1, whereby spinning is performed on the peripheral wall on the other end 1 c side of the cylindrical body 1.

As a result, as shown in FIG. 8D, the peripheral wall on the other end 1c side of the cylindrical body 1 is reduced in diameter to form a second shoulder 17 having a ring shape similar to the shoulder 15, and Second shoulder 17
A second distal end contracted tube portion 18 extending from the small diameter portion is formed.

In the fifth embodiment, the shoulder portion 15 and the second shoulder portion 17 face the end portion 80e of the exhaust gas purifying catalyst 80 or the holding member 83, and the holding performance of the exhaust gas purifying catalyst 80 is improved. ing. In the fifth embodiment, the front end contraction portion 14 is formed on one end 1a side of the cylindrical body 1 by spinning, and the other end 1c of the cylindrical body 1 is formed.
On the side, the second tip contraction portion 18 is formed by spinning, so that the tip contraction portion 14 and the second tip contraction portion 1 are formed.
8 can be strengthened by work hardening. That is, the housing case of the present embodiment has both ends in the axial direction reinforced. Therefore, even if an unexpected external force acts, it is difficult to deform. Of course, the shoulder 15 and the second shoulder 1
7 is also strengthened by work hardening.

In the fifth embodiment, the second front end contracted tube portion 18
Is formed, the central axis P of the non-reduced diameter portion of the cylindrical body 1 is formed.
1 or may be formed eccentrically with respect to the center axis P1 of the unreduced diameter portion of the cylindrical body 1, or the cylindrical body 1 It may be formed eccentric and inclined with respect to the center axis P1 of the reduced diameter portion.

Further, the second tip contracted tube portion 18 according to the fifth embodiment.
Is provided with an inclined wall portion 18a having a gentle inclination with respect to the central axis P1 of the cylindrical body 1, but is not limited to this. The same straight tube shape can be used.

(Other Embodiments) In addition, the method of the present invention is not limited to the embodiments described above and shown in the drawings, but can be carried out with appropriate modifications without departing from the scope of the invention. For example, in the above-described embodiment, the eccentric operation and the tilting operation are performed by moving the cylindrical body 1. However, the present invention is not limited to this, and the main shaft portion 63 having the processing tool 66 is translated or tilted. A mode of performing an eccentric operation and an inclining operation may be adopted.

[0105]

According to the method for manufacturing the exhaust gas purifying catalyst accommodating case according to the first to third aspects of the present invention, a stepped shoulder portion is formed along a direction perpendicular to the central axis of the cylindrical body. . When the shoulder portion is formed along the direction perpendicular to the axis as described above, the diameter reduction start point of the distal end contraction portion shifts radially inward in the direction perpendicular to the axis. For this reason, even when the axial length of the inclined wall portion of the distal end contraction portion is suppressed, the inclination angle of the inclined wall portion of the distal end contraction portion with respect to the center axis of the cylindrical body can be reduced. In other words, it is possible to reduce the diameter reduction ratio of the inclined wall portion of the distal end reduced cylinder portion.

As described above, the stepped shoulder extends along the direction perpendicular to the central axis of the cylindrical body, so that the degree of processing is high when spinning is performed by a processing tool. Therefore, the ratio of the work hardening is high in the shoulder portion, and the hardness is increased and strengthened by the work hardening. Of course, the front end contraction portion is also reinforced by work hardening.

Further, when at least one of the eccentric operation and the tilting operation described above is performed, the diameter and the direction of the front-end contracted tube portion can be changed, so that the mountability to a partner device such as a vehicle can be improved. Can be.

According to the method of manufacturing the exhaust gas purifying catalyst accommodating case according to the second aspect of the present invention, since the eccentric operation is performed, the center axis of the reduced-end cylindrical portion can be eccentric with respect to the cylindrical body. It is possible to improve the mountability to the partner device such as.

According to the method of manufacturing the exhaust gas purifying catalyst accommodating case according to the third aspect of the present invention, since both the eccentric operation and the tilt operation are performed, the diameter and the direction of the front-end contracted tube portion can be changed. It is possible to improve the mountability to the partner device such as.

[Brief description of the drawings]

FIG. 1 is a front view showing a spinning forming apparatus having a chuck means according to a first embodiment.

FIG. 2 is a side view of the spinning molding apparatus according to the first embodiment.

FIG. 3 is a schematic diagram showing each step of spinning molding according to Example 1.

FIG. 4 is a cross-sectional view of the storage case according to the first embodiment.

FIG. 5 is a schematic view showing each process of spinning molding according to Example 2.

FIG. 6 is a schematic diagram showing each process of spinning molding according to Example 3.

FIG. 7 is a schematic view showing each step of spinning molding according to Example 4.

FIG. 8 is a schematic view showing each step of spinning molding according to Example 5.

FIG. 9 is a side view of a storage case schematically illustrating the operation and effect of the present invention.

FIG. 10 is a perspective view showing a partial cross section of a housing case housing a catalyst according to a conventional technique.

FIG. 11 is a cross-sectional view of an accommodating case accommodating a catalyst according to the related art.

FIG. 12 is a side view schematically showing a storage case which does not have a shoulder portion but has an inclined wall portion according to a mode invented by the present inventors.

[Explanation of symbols]

In the figure, 1 is a cylindrical body, 1a is one end, 1c is the other end, 1d is a catalyst accommodating space, 11 is a first intermediate reduced cylinder portion, 12 is a second intermediate reduced cylinder portion, 14 is a front reduced cylinder portion, and 14a is Inclined wall portion, 14c is a neck portion, 15 is a shoulder portion, 17 is a second shoulder portion, 18 is a second reduced end cylinder portion, 5 is a spinning molding device, 66 is a processing tool, 80 is an exhaust gas purification catalyst, and 80e is an end. Reference numeral 83 denotes a holding member.

Claims (7)

[Claims] 1. A metal cylindrical body which is open at one end and the other end extending in the direction of the central axis and has an inside as a catalyst accommodating space,
Using a working tool for spinning molding pressed against the outer surface of the peripheral wall of the tubular body, rotating the working tool around a central axis of the tubular body, and moving the working tool toward the tubular body By performing the spinning molding by the operation to be performed, along the axis perpendicular to the central axis of the cylindrical body,
An end of the exhaust gas purifying catalyst or a stepped shoulder facing a holding member for holding the exhaust gas purifying catalyst is formed on at least one end of a peripheral wall of the cylindrical body. And forming a front end reduced cylinder portion having a slanted wall portion inclined with respect to a center axis of the cylindrical body, the diameter decreasing from the center toward the opening. 2. The method according to claim 1, wherein, in forming the front end contraction section, an eccentric operation of moving the cylinder along a direction perpendicular to an axis of the cylinder is performed. A method of manufacturing a case for accommodating an exhaust gas purifying catalyst, wherein a center axis is eccentric with respect to a center axis of the cylindrical body before forming the shoulder. 3. The inclining operation according to claim 1 or 2, wherein in forming the distal end contraction portion, an inclination operation of inclining the cylinder with respect to a center axis of the cylinder before forming the shoulder portion is performed. A method of manufacturing a casing for an exhaust gas purifying catalyst, characterized in that a center axis of the front contraction portion is inclined with respect to a center axis of the cylinder before forming the shoulder portion. 4. A metal cylindrical body which is open at one end and the other end extending in the direction of the center axis and has a catalyst housing space inside,
Using a working tool for spinning molding pressed against the outer surface of the peripheral wall of the tubular body, rotating the working tool around a central axis of the tubular body, and moving the working tool toward the tubular body By performing the spinning molding by the operation to be performed, along the axis perpendicular to the central axis of the cylindrical body,
An end of the exhaust gas purifying catalyst or a stepped shoulder facing a holding member for holding the exhaust gas purifying catalyst is formed on at least one end of a peripheral wall of the cylindrical body, and further, a small diameter portion of the shoulder is formed. Forming an intermediate constricted cylinder portion extending toward the opening, and thereafter, inclining the center axis of the cylindrical body with respect to the main axis of the processing tool, and in this state, performing the machining on the intermediate condensed cylindrical portion. A spinning process is performed by a tool to form a tip reduced cylinder portion having a center axis inclined with respect to a center axis of the cylinder before forming the shoulder portion and having an inclined wall portion decreasing in diameter toward the opening. A method for manufacturing a casing for accommodating an exhaust gas purifying catalyst. 5. A metal cylindrical body which is open at one end and the other end extending in the direction of the central axis and has an inside as a catalyst accommodating space,
Using a working tool for spinning molding pressed against the outer surface of the peripheral wall of the tubular body, rotating the working tool around a central axis of the tubular body, and moving the working tool toward the tubular body By performing the spinning molding by the operation to be performed, along the axis perpendicular to the central axis of the cylindrical body,
An end of the exhaust gas purifying catalyst or a stepped shoulder facing a holding member for holding the exhaust gas purifying catalyst is formed on at least one end of a peripheral wall of the cylindrical body, and further, a small diameter portion of the shoulder is formed. Forming an intermediate constricted tube portion extending toward the opening, and thereafter, eccentrically inclining and inclining the center axis of the cylindrical body with respect to the main axis of the processing tool, and in this state, the intermediate constricted tube A slanted wall portion having a central axis inclined and eccentric with respect to a central axis of the cylindrical body before forming the shoulder portion, and having a diameter decreasing toward the opening, A method for manufacturing a case for accommodating an exhaust gas purifying catalyst, comprising forming a leading end reduced cylinder portion having a shape. 6. The exhaust gas purifying catalyst according to claim 1, wherein the end member of the exhaust gas purifying catalyst or the holding member that holds the exhaust gas purifying catalyst is formed after the front end contracted tube portion is formed. Storing the exhaust gas purification catalyst in the catalyst storage space from the other end opening of the cylindrical body so as to face the shoulder, and then rotating the processing tool around a central axis of the cylindrical body; An operation of moving the processing tool toward the cylindrical body, thereby performing spinning on the peripheral wall on the other end side of the cylindrical body, reducing the diameter of the peripheral wall on the other end side of the cylindrical body, and reducing the diameter of the second distal end. A method for manufacturing a case for accommodating an exhaust gas purifying catalyst, comprising forming a reduced cylinder portion. 7. A case for accommodating an exhaust gas purifying catalyst according to any one of claims 1 to 6, wherein said cylindrical body is made of a ferritic or austenitic stainless steel as a base material. Method.