JP2957176B1 - Manufacturing method of double structure container - Google Patents

Abstract

Abstract: PROBLEM TO BE SOLVED: To provide a double-structured container having a gap between an inner cylinder and an outer cylinder, to simultaneously perform cross-sectional deformation of the inner and outer cylinders maintaining the gap by spinning on the first floor, thereby facilitating the production. Reduce costs. SOLUTION: An inner cylinder 4A is disposed inside an outer cylinder 4B while maintaining a gap 4C, and a spinning process is performed on the outer cylinder 4B while holding a solid inclusion 4D in at least one section of the gap 4C in the cylinder axis direction. Then, the cross sections of the inner cylinder 4A and the outer cylinder 4B are simultaneously changed.

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 double-structured container, and more particularly to a method for manufacturing a double-structured container by simultaneously changing the cross-sectional shapes of an inner cylinder and an outer cylinder.

[0002]

2. Description of the Related Art In an exhaust system part of an automobile, for example, a muffler or a catalytic converter, an integral inner cylinder whose cross-sectional shape continuously changes in the axial direction and an integral inner cylinder whose both ends are tapered. An insulated tube structure in which an outer cylinder and an outer cylinder are concentrically arranged with a gap therebetween is often used.

[0003] In particular, in a catalytic converter, as shown in FIG. 14, a metal inner cylinder 10 in which a simple catalyst 101 is fitted and tapered reduced diameter portions 102 and 103 are provided at both ends.
4 and a metal outer cylinder 107 having tapered reduced-diameter portions 105 and 106 at both ends.
It is common practice to provide a gap 108 between the reference numerals 07 (see, for example, JP-A-6-101465).

As a method of manufacturing the catalytic converter shown in FIG. 14, a method of reducing the diameter of the outer cylinder 107 by holding a predetermined gap 108 outside the inner cylinder 104 whose diameter has been reduced in advance is not suitable. There is a problem that it is difficult and the production cost increases. In particular, the bottleneck is the molding of the outer cylinder 107. In other words, it is desired to form the outer cylinder 107 having a cross-sectional shape which follows the cross-sectional change of the inner cylinder 104 to a certain extent and keeps a desired gap 108, so that the desired gap 108 is formed over the entire length in the axial direction. Integrated outer cylinder 1
07 was extremely difficult to mold.

[0005] Therefore, as a convenient manufacturing method, an outer cylinder formed in a half-shape in a monaka shape in the axial direction is arranged outside a pre-molded inner cylinder with a space secured, and the two monaka bodies are welded together. Although the technique of joining by means of welding is generally used, expensive equipment such as a press die and a welding device is required, and the pressing step and the welding step require a great deal of labor and time.

Therefore, by avoiding the above-described manufacturing method, as shown in FIG.
02, a reduced diameter portion 204 is formed at the base of the outer cylinder 203, and these two cylinders 201 and 203 are fitted as shown in FIG. 15 to obtain a double-tube catalytic converter having a predetermined gap 205. A manufacturing technique has been proposed (for example, Japanese Patent Application Laid-Open No. 9-108576).

However, in the manufacturing method shown in FIG. 15, contact between the enlarged diameter portion 202 of the inner cylinder 201 and the outer cylinder 203 and contact between the reduced diameter portion 204 of the outer cylinder 203 and the inner cylinder 201 cannot be avoided. Since heat transfer occurs from the contact portion, the gap 2
There is a problem that the heat insulating effect is reduced even when the heat insulating structure is provided by providing the heat insulating structure 05.

As a method of manufacturing a thermos, there is a method in which an inner cylinder having only one side opened and an outer cylinder having only one end opened are each formed in an arbitrary cross section by spinning, and these are polymerized. For example, JP-A-10-15
631 and JP-A-7-284452.

However, in this manufacturing method, spinning of the inner cylinder and the outer cylinder is required, which complicates the process and requires a separate step of reducing the diameter of the outer cylinder after inserting the inner cylinder. Ease of processing and reduction of processing cost cannot be achieved by this method.

From the above, it is possible to easily and inexpensively manufacture a double-structured container having a predetermined gap between the inner cylinder and the outer cylinder, and in which the inner cylinder and the outer cylinder are integrally formed in a sectional shape. The way was craving.

[0011]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for manufacturing a double-structured container which meets the above-mentioned craving. The inner cylinder is arranged while maintaining the gap, and the outer cylinder is subjected to spinning while holding the solid inclusion in at least one section in the cylinder axis direction in the gap, thereby simultaneously changing the cross section of the inner cylinder and the outer cylinder. It is characterized by the following.

In the present invention, the cross section of the outer cylinder is changed by the pressing force by rotating the inner and outer cylinders holding the solid inclusions around the cylinder axis and pressing the spinning roller against the outer cylinder for spinning. Further, a force is transmitted from the outer cylinder to the inner cylinder via a deformable solid inclusion held in the gap, and the cross section of the inner cylinder changes simultaneously. Thereby, the inner and outer cylinders can be simultaneously formed into a desired cross-sectional shape by one spinning process.

According to a second aspect of the present invention, the inner cylinder is arranged in the outer cylinder while maintaining a gap in the outer cylinder, and the solid cylinder is held in at least one section of the gap in the axial direction of the cylinder. The spinning process is performed so that the cross sections of the inner cylinder and the outer cylinder are simultaneously changed eccentrically with respect to the cylinder axis of the material of the inner and outer cylinders.

In the present invention, the inner and outer cylinders eccentrically changed with respect to the cylinder axis of the material can be simultaneously formed by one spinning process by the same operation as the first invention.
According to a third aspect of the present invention, the inner cylinder is arranged in the outer cylinder with a gap kept therebetween, and a spinning process is performed on the outer cylinder with the solid inclusion sandwiched in at least one section of the gap in the cylinder axis direction. In which the cross sections of the inner cylinder and the outer cylinder are simultaneously bent and changed with respect to the cylinder axis of the material of the inner and outer cylinders.

In the present invention, the inner and outer cylinders bent and changed with respect to the cylinder axis of the material can be simultaneously formed by a single spinning process by the same operation as the first invention. According to a fourth aspect of the present invention, in the first, second, or third aspect, a metal core is inserted into at least one section of at least one of the inner cylinder and the outer cylinder. is there.

In the present invention, furthermore, by inserting the core metal during spinning, by inserting the core metal between the inner cylinder and the outer cylinder or into the inner cylinder, excessive deformation of the inner cylinder and the outer cylinder is prevented. it can.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the solid inclusion is a solidified state of a heat-meltable resin or a thermoplastic resin. It is.

In the present invention, the solid inclusions are further heated to soften and melt, thereby filling the solid inclusions into the voids before the forming of the inner and outer cylinders and filling the solid inclusions after the forming. Can be easily removed.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described based on the embodiments shown in FIGS.

First, a spinning machine for carrying out the manufacturing method of the present invention will be described with reference to FIGS. FIG.
FIG. 2 is a partially cutaway side view of the spinning machine, FIG. 2 is a plan view of the same part cut away, and a material (work) drive unit 2 is provided on one side of the fixed base 1 and on the other side. Is provided with a roll drive unit 3.

[0021] On the base 1 of the material drive unit 2 side, the direction parallel to the revolution axis X ₅ of the roll 28 (referred to as X direction) X-direction slide rail 5 Article 2 parallel along later It is fixed. An X-direction slider 6 is mounted on the X-direction slide rail 5 so as to be slidable in the X-direction, and a ball spline shaft 8 is screwed to a boss 7 provided on the X-direction slider 6, and a motor or the like is provided. By rotating the ball spline shaft 8 forward and backward by a desired amount by the driving means 9, the X direction slider 6 can be moved forward and backward by a desired amount in the X direction.

On the X-direction slider 6, a Y-direction is set along a horizontal direction (hereinafter referred to as a Y-direction) orthogonal to the X-direction.
Two directional slide rails 10 are fixed in parallel. A Y-direction slider 11 is slidably mounted on the Y-direction slide rail 10 in the Y-direction. Further, the Y
A bed 30 is mounted and fixed on the directional slider 11, and a ball spline shaft 15 is screwed into a boss 14 fixed to the lower surface of the bed 30. The ball spline shaft 15 is desirably driven by driving means 16 such as a motor. By rotating the bed forward and backward, the bed 30 can be moved forward and backward by a desired amount in the Y direction.

The bed 30 is provided with a rotation driving means 31 such as a motor, and the rotation driving means 31
The rotary drive shaft 31a of the rotary member protrudes vertically above the bed 30. By the rotation driving means 31 and the rotation driving shaft 31a,
It constitutes means for tilting the material 4.

A clamp device 1 is provided on the upper surface of the bed 30.
The lower clamp 13 is slidably mounted, and the drive shaft 31a is fixed to the lower clamp 13. The rotation drive shaft 31a is rotated by forward and reverse rotation of the rotation drive shaft 31a. The lower clamp 13 rotates forward and backward in a horizontal plane around the center.

The bed 30 has a rotating drive shaft 31 thereon.
An arc-shaped guide groove 32 having a center at a is formed, and a guide roller 33 projecting from the lower surface of the lower clamp 13 is rotatably fitted in the guide groove 32. Further, the rotation drive shaft 31a has its axis is as shown in FIG. 2, is set in a position at right angles with the tube axis X ₄ of the material 4 to be placed on the lower clamp 13 to be described later.

On the upper surface of the lower clamp 13, a semicircular clamp surface 13a for supporting the lower half surface of the material 4 is provided. When the material 4 is placed on the clamp surface 13a, the cylinder axis X4 of the material ₄ will be described later. be exactly the same height and the axis X ₅ of the rotary shaft 21 is formed. Further, an upper clamp 17 having a clamp surface 17a formed on the lower surface thereof for pressing and holding the upper semicircle of the material 4 is disposed on the lower clamp 13 such that the upper clamp 17 can be moved up and down. The upper clamp 17 descends, and the upper clamp 17 and the lower clamp 13 clamp the material 4 to a set position in a non-rotatable manner, and the upper clamp 17 raises the material. 4 can be attached and detached.

A stopper 19 is provided at a rear portion of the clamp device 12, and by positioning the rear end of the material 4 against the stopper 19, the material 4 can be easily positioned in the axial direction. The stopper 19 is moved in phase with the clamping device 12 provided in the lower clamp 13, for example, also be positioned adjustably configured in the cylinder axis X ₄ direction of the material 4.

Next, the roll driving section 3 will be described.
A rotating equipment unit 20 is installed on the base 1,
A rotation shaft 21 is provided rotatably with its axis centered in the X direction. The rotating shaft 21 is configured to be rotated in one direction via a belt 23 by a motor 22 that is a rotation driving unit. A roll holder 2 is provided on the material drive unit 2 side of the rotary shaft 21.
4 is fixed, the roll holder 24 is rotated about the axis X ₅ of the rotary shaft 21 by the rotation of the rotary shaft 21.

The rotary equipment section 20 is provided with trajectory changing means for changing the driving trajectory of the roll. The trajectory changing means includes a cylinder 25 as a driving means and a roll holder at the tip of a rod 25a of the cylinder 25. And a ring plate 26 provided in the roll holder 24 so as not to hinder the rotation of the roller 24. The ring plate 26
Is formed in an annular shape concentric with the rotary shaft 21, and the inner surface at the front end thereof is formed as a tapered surface 26 a expanding outward.

The roll holder 24 is provided with a plurality of, in the illustrated embodiment, three brackets 27, the axes of which are arranged in the X direction, and are arranged at equal intervals in the circumferential direction of the roll holder 24. Further, each bracket 27 is provided with a roll holder 24.
Is provided movably axis X ₅ of radially centered. Further, a tapered surface 27a is formed along the tapered surface 26a inside the roll holder 24 of each bracket 27, and a roll 28 is provided at the outer end of each bracket 27 so as to freely rotate (self-rotate). ing.

Although not shown, each of the brackets 2
7 is provided with a means for constantly biasing the roll holder 24 to the outer peripheral side thereof, for example, a return spring.
When the ring plate 26 is moved forward (to the left in FIG. 1) by the cylinder 25, the brackets 27, that is, the rolls 28 are closed and moved by the same amount in the axial direction of the rotary shaft 21 by the tapered surfaces 26a, 27a. When the ring plate 26 is moved backward (to the right in FIG. 1), the brackets 27, that is, the rolls 28 are moved outward by the same amount by the two tapered surfaces 26a, 27a.

Next, a method of manufacturing a double-structured container by simultaneously deforming the inner cylinder and the outer cylinder in cross section using the spinning machine will be described. FIG. 4 shows a first embodiment of the manufacturing method.

FIG. 4A shows a first step, in which a metal outer cylinder 4B made of metal and having a larger diameter than the inner cylinder 4A is arranged concentrically outside the inner cylinder 4A made of metal. And these two cylinders 4
A state in which solid inclusions 4D are filled in an annular space 4C having a predetermined width formed between A and 4B is shown. The material in this state is referred to as a material 4.

As the solid inclusions 4D, for example, a heat-meltable resin is used, and when filling the solid inclusions 4D, the inner and outer cylinders 4A and 4B are formed so that a predetermined gap 4C is formed therebetween. And one end of the gap 4C is closed by an appropriate means, and a resin in a heated and molten state is poured into the gap 4C from the other open end, and is cooled and solidified to form a solid inclusion 4D between the inner and outer cylinders 4A and 4B. Intervene.

The solid inclusion 4D has a good filling property and a good discharging property, and can be deformed to some extent when filled to a solid state, and has a small compressibility (an incompressible material). Is preferable, and the above-mentioned heat-fusible resin is preferable, but other resins may be used. Note that the melting point of the heat-meltable resin is desirably higher than the temperature of the raw material 4 raised by spinning. As the heat-meltable resin, for example, those commercially available under the trade name "Seal Peal Hot" can be used.

Next, as shown in FIG. 4 (B), the process shifts to a second step in which the material 4 is clamped by the clamping device 12 of the spinning machine and the end of the material 4 is reduced in diameter. Before the diameter reduction operation, the ring plate 26 of the spinning machine is located to the right of the position shown in FIG.
Numeral 8 is open to the outside of the outer diameter of the material 4.

The clamp surface 13 of the lower clamp 13
a, the material 4 is fitted and mounted on the
Then, the rear end is brought into contact with a stopper 19 set at a predetermined position, and thereafter, the driving means 18 is operated to move the upper clamp 17 downward, and the raw material 4 is non-rotatably clamped by the upper and lower clamps 13, 17. Further, the clamping device 1 is driven by the driving means 16.
2 of the Y-direction position, an extension of the axis of the rotary drive shaft 31a is set at a position intersecting the extension line of the axis X ₅ of the rotary shaft 21.

If necessary, as shown in FIG. 4B, the core metal 51 is inserted into the inner cylinder 4A on the spinning side. The cored bar 51 includes a reduced diameter portion 51a corresponding to the reduced diameter of the inner cylinder 4A, a tapered portion 51b positioned outside the reduced diameter portion 51a,
The large diameter portion 51c is located outside the large diameter portion 51c.
1 c is formed to have an outer diameter substantially equal to the inner diameter of the material 4.

[0039] In the following, the drive means 9, along the X direction by rotating the ball spline shaft 8 in one direction parallel to the clamping device 12 to the axis X ₅ of the rotary shaft 21 moves to the right in FIG. 1, As shown in FIG. 4B, each roll 28 is positioned at the starting point A of the diameter reduction of the material 4.

From this state, the motor 22 as the driving means is
To rotate the roll holder 24 in one direction and actuate the driving means 25 to advance the ring plate 26 to close the revolving locus of each roll 28 toward the center of the roll holder 24; 9 is driven to rotate the ball spline shaft 8 in the other direction, and the clamp device 12 is retracted to the left in FIG.

[0041] Thus, each roll 28 is the revolving locus diameter gradually decreases with revolves around the cylindrical axis X ₅ while rotating pressed against the outer peripheral surface of the outer tube 4B in material 4,
Spinning is performed from the diameter reduction start point A as shown in FIG.

The outer cylinder 4B is reduced in diameter by this spinning process, and the deformation force is transmitted to the inner cylinder 4A via the solid inclusion 4D, so that the inner and outer cylinders 4A, 4B and the solid inclusion 4D are simultaneously deformed.

That is, the elemental cylinder portion 4a of the inner and outer cylinders 4A and 4B
A tapered portion 4b which is reduced in diameter from above and a neck portion 4c extending from the tip of the tapered portion 4b are formed in series with the solid inclusion 4D held between the inner and outer cylinders 4A and 4B.

When the core metal 51 is inserted during the spinning, the diameter reduction of the neck 4c is accurately performed by the diameter reduction portion 51a of the core metal 51. Further, as shown in FIG.
Move along the tapered portion 51b as shown by the arrow in the figure, and separate from the large-diameter portion 51c of the metal core 51 outward. Next, FIG.
The inner and outer cylinders 4A and 4B are cut at the portion C shown in (B), and the waste margin 4e is removed.

Next, as a third step, the raw material 4 formed in the second step is removed from the clamp device 12, inverted in the axial direction, and clamped again by the clamp device 12. As shown in FIG. 4C, the other cylindrical end of the material 4 on the side opposite to the processed side is subjected to spinning to reduce the diameter in the same manner as in the second step. At this time, if necessary
The core metal 51 is used as in the second step. Next, FIG.
The inner and outer cylinders 4A and 4B are cut at the portion D shown in FIG. 4C, and the throwaway portion 4f is removed. The cutting of the inner and outer cylinders 4A and 4B in the second step and the third step may be performed together after the third step. Although the above-mentioned disposal margins 4e and 4f are not always necessary, it is desirable to provide the disposal margins 4e and 4f and cut and remove them in order to accurately form the shape of the cylinder end.

As described above, both ends of the raw material 4 are reduced in diameter by the two spinning processes. Then, after the molding, the molded article is removed from the clamp device 12, and the solid inclusion 4D may be left as the final product in the void 3C in the third step.
As shown in (D), as the fourth step, solid inclusions 4D
May be removed, and a product in which a gap 4C is formed between the inner and outer cylinders 4A and 4B may be used as a final product.

When the solid inclusion D4 is a heat-melted resin, by heating the product in the fourth step, the solid inclusion 4 can be melted and easily flowed out. When a member having excellent heat insulation properties, for example, a heat insulating mat is used as the solid inclusion 4D, it is desirable to leave it as it is, but when it is used as a container for an exhaust system of an automobile, high heat resistance is required. Therefore, the solid inclusions 4D are removed.

FIG. 4D formed as described above.
In the above product, both ends of the inner and outer cylinders 4A and 4B are connected to another connecting pipe or the like such that a gap 4C is held between them.

FIG. 5 shows a manufacturing method according to the second embodiment. The second embodiment is an embodiment in which the interior is accommodated in the inner cylinder 4A of the first embodiment, and shows an example in which the present invention is applied to a catalytic converter of an exhaust system of an automobile.

As a first step of FIG.
In the first step of the first embodiment shown in (A), the catalyst carrier 50 is inserted or press-fitted. After that, a second step (FIG. 5B), a third step (FIG. 5C), and a fourth step (FIG. 5D) similar to those of the first embodiment are performed, as shown in FIG. As shown,
A double pipe having the catalyst carrier 50 therein and having a gap 4C between the inner and outer cylinders 4A and 4B is manufactured.

The core metal 51 is not always necessary, and may be optionally used as needed. FIG. 6 shows a third embodiment.

In the third embodiment, an interior material such as the catalyst carrier 50 as in the second embodiment is accommodated, and one end of the inner and outer cylinders 4A and 4B is connected to a gap between the inner and outer cylinders 4A and 4B. 4
This is an embodiment in the case of extending long with C, for example, in the case of integrally providing a resonance type muffler at the rear of the catalytic converter 50 of the second embodiment. In FIG. 6, a range indicated by reference numeral 54 is a portion of the resonance type muffler.

The manufacturing process of the third embodiment is basically the same as the manufacturing process of the second embodiment, except that a resonance hole 52 is formed in the inner cylinder 4A in advance, and the inner hole 4A is formed at the time of spinning. As the core metal 51 described in the second embodiment, a core metal whose insertion portion is extended is used, and the resonance hole 52 is formed at the extension portion by the inner cylinder 4A.
So as to block from inside.

The inner and outer cylinders 4 formed according to the third embodiment.
One end of each of A and 4B, for example, the left end in FIG. 6, is fixed to another connecting pipe, while the other end, for example, the right end in FIG.
A wire net ring 53 for holding the outer cylinder 4B and the outer cylinder 4B so as to be movable with each other is sandwiched, so that the inner cylinder 4A and the outer cylinder 4B can follow each other due to the difference in thermal expansion between them.

In the embodiment of FIG. 6, the catalyst carrier 5
The thickness (gap distance between the inner and outer cylinders) of the gap 4C on the left side (A side) from 0 is gradually changed. Reduce the diameter,
The inner cylinder 4A is inserted into the outer cylinder 4B, and the reduced diameter portion of the inner cylinder 4A is held by holding means (not shown), and a gap between the inner cylinder 4A and the outer cylinder 4B is provided on the right side (B side) of the catalyst carrier 50. 4C is filled with the solid inclusion 4D, and the outer cylinder 4B is subjected to the spinning process as described above.

In the product manufactured in the third embodiment, the exhaust gas is purified by the catalyst carrier 50 and the exhaust noise is reduced by the resonance hole 5.
2 flows into the gap 4C in the resonance type muffler portion 54, and the gap 4C becomes a resonance space and is silenced. In addition, the voids 4C also exhibit the original heat insulating effect.

As described above, by arbitrarily setting the filling range of the solid inclusions 4D and the use range and shape of the core bar 51, the inner and outer cylinders 4A and 4B having the voids 4C can be formed as desired.

FIG. 7 shows a fourth embodiment. The fourth embodiment shows an example of manufacturing a double pipe in which the axes of the inner cylinder 4A and the outer cylinder 4B are mutually eccentric.

As a manufacturing method of this embodiment, an inner cylinder 4A and an outer cylinder 4B are used in the first step of the first and second embodiments.
Are mutually eccentrically desired, the solid inclusions 4D are filled in the voids 4C, and then manufactured by the same steps as described in the first and second embodiments.

FIG. 8 shows a sixth embodiment. The sixth embodiment is an example in which one reduced diameter portion and the other reduced diameter portion of the double cylinder (container) are eccentric.

The manufacturing process will be described. First, as shown in FIG. 5 (A), as the raw material 4, a solid inclusion 4D is interposed between the inner cylinder 4A and the outer cylinder 4B, and an inner material such as a catalyst carrier 50 is used in the inner cylinder 4A. I do.

In FIG. 1, before the tube reduction operation, the ring plate 26 is located on the right side of the position shown in FIG.
Each roll 28 is retracted and opened outside the outer diameter of the material 4.

The clamp surface 13 of the lower clamp 13
a unprocessed material 4 is fitted and mounted on the
With the stopper 19 set at a predetermined position.
Then, the drive means 18 is operated to move the upper clamp 17
Moves down and material 4 cannot be rotated by upper and lower clamps 13 and 17
To be pinched. Further, the rotation driving means 31 is operated to
The cylinder unit X of the material 4 sandwiched between the_FourTurns
Shaft core X of shaft 21 _FiveAnd rotate in parallel. Change
Then, the driving device 16 is operated to move the clamp device 12
Shaft 4 of material 4_FourIs the axis X of the rotating shaft 21_FiveNihei
And the specified amount OF₁(See FIG. 9 (A)).
(Fset) in the Y direction.

Next, the ball spline shaft 8 is rotated in one direction by the driving means 9 to move the clamp device 12 to the right side in FIG. 1 along the X direction, and the material 4 is moved in parallel with its cylindrical axis. The material 4 is moved forward (to the right in FIG. 1) by a predetermined amount toward the roll holder 24 to start the diameter reduction start point A of the material 4 (see FIG. 9A).
Is positioned at each roll.

From the state shown in FIG. 9A, the motor 22 as the driving means is driven to rotate the roll holder 24 in one direction, and the driving means 25 is operated to advance the ring plate 26 so that each roll 28 is moved forward. Is closed in the direction of the center of the roll holder 24, and the driving means 9 is driven to rotate the ball spline shaft 8 in the other direction. Retract to the left.

[0066] Thus, each roll 28 is the revolving locus diameter gradually decreases with revolves around the cylindrical axis X ₅ while rotating pressed against the outer peripheral surface of the outer tube 4B in material 4,
As shown in FIG. 9B, spinning is performed from the diameter reduction start point A. At this time, the revolution axis X ₅ of the roll 28 Material 4
Because from the tube axis X ₄ are eccentric only OF _1, spinning in-cylinder ends, as shown in FIG. 9 (B), blank 4
Is plastically deformed in the base pipe portion (barrel portion) 4a of the tubular shaft X ₄ from OF ₁ only eccentric the revolution axis X ₅ the court and the axial head conical tapered portion 4b.

After the tapered portion 4b is formed, the roll 4 is kept closed and the material 4 is continuously retracted, so that the tip of the tapered portion 4b has the cylindrical shaft X
₄ a cylindrical neck portion 4c to parallel and the revolution axis X ₅ axes
Are formed by plastic deformation.

Then, the material 4 and the roll 28 are moved backward by the movement reverse to the forward movement of the diameter reduction movement, and this one reciprocating movement is regarded as one pass, and the first spinning process is completed. After completion of the first spinning process, the rolls 28 are returned to the open position, the driving means 9 is operated to rotate the ball spline shaft 8 in one direction, and the material 4 is clamped together with the clamp device 12 into the cylinder. The roll 28 is further advanced by a predetermined amount in parallel with the axis, and each roll 28 is positioned at the point B in FIG. 9C. Further, the driving means 16 is operated to rotate the ball spline shaft 15 in one direction, and the material 4 is further moved together with the clamp device 12 in the Y direction by a predetermined amount, as shown in FIG. Eccentricity OF ₂ between the cylindrical axis X ₄ and the axis of the rotary shaft 21, that is, the revolving axis X ₅ of the roll 28.
The larger than the eccentricity OF _1.

In this state, the amount of closing movement of the roll 28 is made larger than that in the first step, and the same spinning process is performed. Thus, the tapered portion 4b is a frustoconical about the axis X ₅ which eccentric by OF ₂ weight than Mototo portion (barrel portion) 4a tube axis X ₄ of the blank 4, and a large taper angle It is plastically deformed into the tapered portion 4b. After forming the tapered portion 4b, the roll 4 is kept closed and the material 4 is continuously retracted, so that the neck portion 4c having a smaller diameter than that of FIG.
Is molded.

By the above steps, the end portion (right side portion in FIG. 8)
A reduced diameter portion 4d integrally formed with the eccentric taper portion 4b and the eccentric neck portion 4c is formed. In the spinning process,
The outer cylinder 4B is reduced in diameter and its deformation force is transmitted to the inner cylinder 4A via the solid inclusion 4D, and the inner and outer cylinders 4A and 4B are deformed.
And the solid inclusions 4D are simultaneously deformed.

That is, the elemental cylinder portion 4a of the inner and outer cylinders 4A and 4B
A tapered portion 4b which is reduced in diameter from above and a neck portion 4c extending from the tip of the tapered portion 4b are formed in series with the solid inclusion 4D held between the inner and outer cylinders 4A and 4B.

Next, the raw material 4 formed in the above step is removed from the clamp device 12, turned over in the axial direction, and held again by the clamp device 12, and the raw material on the side opposite to the side processed in the above step is removed. The other end of the cylinder 4 is spinned in the same manner as described above to reduce the diameter.

At this time, in FIG. 1, the cylindrical shaft X ₄ of the raw material 4 and the shaft center X ₅ of the rotary shaft 21 are positioned concentrically and are subjected to spinning, thereby obtaining the left side of FIG. The tapered portion 4b and the neck 4c, which are concentric with the elementary tube portion 4a, are formed.

After the above-mentioned molding, the molded article is removed from the clamp device 12, and the solid inclusion 4D may be left as it is in the gap 4C as the final product in the third step. As shown, the solid inclusion 4D may be removed, and a product in which a gap 4C is formed between the inner and outer cylinders 4A and 4B may be used as a final product.

FIG. 10 shows a seventh embodiment. The seventh embodiment shows an example in which a reduced diameter portion and a neck portion at both ends are eccentrically bent. The manufacturing process in this embodiment will be described.

In FIGS. 1 and 2, before the diameter reduction operation, the ring plate 26 is located on the right side of the position shown in FIG. 1, and each roll 28 is formed of the material 4 as shown in FIG. It retracts outside the outer diameter.

Then, the clamp surface 13 of the lower clamp 13
4A, the same material 4 as that of FIG. 4A is fitted and placed, and the rear end of the material 4 is brought into contact with a stopper 19 set at a predetermined position. 17 and lower the material 4 to the upper and lower clamps 1
At 3 and 17, it is pinched non-rotatably. Further, the Y-direction position of the clamping device 12 by the drive means 16, as shown in FIG. 11 (A), an extension of the axis of the rotary drive shaft 31a is an extension of the axis X ₅ of the rotary shaft 21 intersecting Set to the position you want. Further, the rotation driving means 31 is actuated, and as shown in FIG. 11 (A), the cylinder axis X ₄ of the material 4 is horizontally shifted by a predetermined angle θ _{1 with} respect to the axis X ₅ of the rotating shaft 21. The clamp device 12 is tilted horizontally so as to be tilted.

Next, the ball spline shaft 8 is rotated in one direction by the driving means 9 to move the clamp device 12 rightward in FIG. 1 along the X direction parallel to the axis X ₅ of the rotary shaft 21. As shown in FIG. 11A, each roll 28 is positioned at the starting point A of diameter reduction of the material 4.

From this state (the state shown in FIG. 11A), the motor 22 as the driving means is driven to rotate the roll holder 24 in one direction, and the driving means 25 is operated to advance the ring plate 26. The revolving locus of each roll 28 is closed in the direction of the center of the roll holder 24, and the driving means 9 is driven to rotate the ball spline shaft 8 in the other direction so that the clamping device 12 is moved together with the material 4 in the X direction. It is retracted to the left in FIG.

[0080] Thus, each roll 28 is the revolving locus diameter gradually decreases with revolves around the cylindrical axis X ₅ while rotating in press contact with the outer peripheral surface of the material 4, Fig from condensation-diameter starting point A 14 ( Spinning is performed as shown in B). At this time, since the tube axis X ₄ of the material 4 is inclined by theta ₁ with respect to the revolution axis X ₅ of the roll 28, spinning in-cylinder ends, as shown in FIG. 11 (B), blank 4 Mototo portion (barrel portion) 4a revolution axis X which only inclined theta ₁ from the cylinder axis X ₄ of the
It is plastically deformed into a frusto-conical tapered portion 4b with ₅ as an axis.

[0081] Furthermore, after forming of the tapered portion 4b, by subsequently retracted in the X-direction material 4 maintains a closed position of the roll 28, the front portion of the tapered portion 4b, the workpiece 4 cylinder axis X ₄ cylindrical neck portion 4c having axes of revolution shaft X ₅ inclined by theta ₁ and is formed by plastic deformation.

Then, the material 4 and the roll 28 are moved backward by the movement reverse to the forward movement of the diameter reduction movement, and the first reciprocating movement is regarded as one pass, thereby completing the first spinning process. After the completion of the first spinning process, the rolls 28 are returned to the open position, the driving means 9 is operated to rotate the ball spline shaft 8 in one direction, and the clamping device 12 is rotated.
At the same time, the material 4 is further advanced in the X direction by a predetermined amount, each roll 28 is positioned at the point B in FIG. 11C, and the rotation drive shaft 31 is operated to further tilt the material 4 together with the clamp device 12 by a predetermined amount. Then, as shown in FIG.
Tube axis X ₄ and the axis of the rotating shaft 21 of the material 4, i.e., the angle theta ₂ between the revolution axis X ₅ of the roll 28 is larger than the angle theta ₁ of the first step.

In this state, the amount of closing movement of the roll 28 is made larger than that in the first step, and the same spinning process is performed. Thus, the has been tapered portion 4b is formed in the first step, Mototo portion of the raw material 4 (barrel) 4a axes X ₅ inclined by theta ₂ from the cylinder axis X ₄ in truncated cone shape with the center of And is plastically deformed into a tapered portion 4b having a large taper angle. Further, after molding of the tapered portion 4b, by subsequently retracted in the X-direction material 4 maintains a closed position of the roll 28, the front portion of the tapered portion 4b, around the axis X ₅ above, and The neck 4c having a smaller diameter than the first step is formed.

By the above steps, as shown in FIG.
The X ₄ on an end portion of the trunk 4a whose axes, reduced diameter portion 4d formed integrally with the tapered portion 4b and neck portion 4c about the axis X ₅ that is inclined relative to the axis X ₄ is molded.

Next, the material 4 reduced in diameter by the above process
13 is again reversed and clamped by the clamp device 12, and the same spinning process is performed as described above, so that the tapered portions 4d, 4d and the neck portions 4c, 4c, which are eccentrically bent at both ends, as shown in FIG. Can be molded.

Then, after the molding, the product is taken out from the clamp device 12, and the solid inclusion 4D may be left as it is in the void 3C as a final product. Alternatively, as shown in FIG. 4D may be removed and a product having a gap 4C formed between the inner and outer cylinders 4A and 4B may be used as a final product.

The solid inclusions 4D in the above embodiment were used.
May use a thermoplastic resin. Further, a heat insulating member may be used instead of this resin. When this heat insulating member is used, it is preferable to press-fit the heat insulating member around the inner cylinder 4A of the raw material 4 into the outer cylinder 4B with the heat insulating member wound and fixed. Furthermore, since a heat insulating material is originally required in a muffler or a catalytic converter, it is not necessary to remove the solid inclusions 4D even after the forming process. In such a case, the step of removing the solid inclusions 4D can be omitted.

Further, as the solid inclusions 4D, ice which has been frozen after water has been injected into the voids 4C may be used, or metal particles (shots) may be used. In the above embodiment, the core is inserted into the inner cylinder 4A, but the core may be inserted into the outer cylinder 4B.

In each of the above embodiments, the material 4 is moved in the cylinder axis direction during spinning. However, the material 4 may be fixed and the spinning roller 28 may be moved in the cylinder axis direction. May also be moved. Further, a drive locus of the roller, that is, a means for continuously controlling the roller in the deformation direction is also optional.

In each of the above embodiments, the spinning roller 28 is revolved while the material 4 is fixed.
May be rotated around its axis and the core metal 51 may also be rotated in the same way, so that the spinning roller 28 rotates without revolving, and moves in the radial direction and the cylinder axis direction. Each of the above embodiments is an example of application to a container of an exhaust system part of an automobile. However, the present invention is also applicable to a general-purpose container and a daily necessity such as a pot, and the application is limited. It does not do.

[0091]

As described above, according to the first aspect of the present invention, a double-structured container having a gap between the inner and outer cylinders is simultaneously deformed into a desired cross section by a single spinning process. Therefore, the processing can be facilitated and the processing time can be shortened, and the processing cost can be greatly reduced.

According to the second aspect of the present invention, the inner and outer cylinders which are eccentrically changed with respect to the cylinder axis of the material can be manufactured with the above effects. According to the third aspect of the present invention, the inner and outer cylinders bent and changed with respect to the cylinder axis of the material can be manufactured with the above-described effects.

According to the fourth aspect of the present invention, furthermore, the inner and outer cylinders can be prevented from being excessively changed by the cored bar, and a desired sectional shape can be reliably obtained. Further, by selecting the arrangement of the core metal, it is possible to change the deformation amount of the inner and outer cylinders to form different cross-sectional shapes, and it is also possible to make the cross-sectional shapes of the inner and outer cylinders different by one spinning process.

According to the fifth aspect of the present invention, the work of filling and removing solid inclusions can be performed easily and quickly, and the work efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an example of a spinning machine used in a manufacturing method of the present invention.

FIG. 2 is a partially broken plan view of FIG.

FIG. 3 is a schematic perspective view of a clamp portion and a roll portion of the material in FIG.

FIGS. 4A to 4D are process diagrams showing a first embodiment of the present invention.

FIGS. 5A to 5D are process diagrams showing a second embodiment of the present invention.

FIG. 6 is a longitudinal sectional view showing a third embodiment of the present invention.

FIG. 7 is a transverse sectional view showing a fourth embodiment of the present invention.

FIG. 8 is a longitudinal sectional view showing a fifth embodiment of the present invention.

FIGS. 9A to 9C are process diagrams in the embodiment of FIG. 8;

FIG. 10 is a longitudinal sectional view showing a sixth embodiment of the present invention.

FIG. 11 is a process chart in the embodiment in FIG. 10;

FIG. 12 is a perspective view of a material formed by the method of FIG. 10;

FIG. 13 is a diagram showing a state in which the contraction step of FIG.
0 is a diagram illustrating a product according to the example of FIG.

FIG. 14 is a longitudinal sectional view showing a first conventional manufacturing method.

FIG. 15 is a longitudinal sectional view showing a second conventional manufacturing method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 4 ... Element cylinder 4A ... Inner cylinder 4B ... Outer cylinder 4C ... Void 4D ... Solid inclusion 12 ... Clamping device 28 ... Spinning roller 51 ... Core metal

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-11-147138 (JP, A) JP-A-11-151535 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B21D 22/16 B21D 51/18 B21D 53/84 F01N 3/28 301 F01N 7/18

Claims (5)

(57) [Claims] An inner cylinder is provided in an outer cylinder with a gap maintained therein, and a spinning process is performed on the outer cylinder in a state where solid inclusions are sandwiched in at least one section of the gap in the cylinder axis direction. And simultaneously changing the cross section of the outer cylinder. 2. An inner cylinder, wherein an inner cylinder is disposed inside an outer cylinder while maintaining a gap, and spinning is performed on the outer cylinder in a state in which solid inclusions are sandwiched in at least one section of the gap in the cylinder axis direction. Wherein the cross section of the outer cylinder and the outer cylinder are simultaneously changed eccentrically with respect to the cylinder axis of the material of the inner and outer cylinders. 3. An inner cylinder is provided in the outer cylinder with a gap maintained therein, and spinning is performed on the outer cylinder in a state where solid inclusions are sandwiched in at least one section of the gap in the cylinder axis direction. And a cross section of the outer cylinder is bent and changed obliquely with respect to a cylinder axis of a material of the inner and outer cylinders. 4. The method according to claim 1, wherein a core is inserted into at least one section of at least one of the inner cylinder and the outer cylinder. 5. The method for producing a double-structure container according to claim 1, wherein the solid inclusion is a solidified state of a heat-meltable resin or a thermoplastic resin.