JP2000317532A - Method for forming tube end and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a reduced diameter part which is offset to the axial center of the main body part of a tube in a tube end part. SOLUTION: This device consists of work holding means for holding a work W consisting of a metallic tube and a rotating part for rotating the work holding means. By executing spinning by pressing a roller against the outer periphery of the end part of the work while revolving the work W around the rotating shaft of a rotating part by decentering the axial center X5 of the work holding means from the axial center X4 of rotation of the rotating part, the reduced diameter part is formed on the work.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for forming a pipe end, and more particularly to a method and an apparatus for eccentrically reducing the end of a metal pipe by spinning.

[0002]

2. Description of the Related Art As a method of forming a reduced diameter portion at an end of a cylindrical metal tube material (hereinafter referred to as a work), a conventional method shown in FIG.
As shown in the figure, the work 100 is supported by the chuck 102 of the rotation support means 101, and the axis X _{1 of the} work 100 is supported.
While rotating about -X ₁ , one or a plurality of processing rolls 103 arranged on the side to be reduced are radially moved around the axis X ₁ -X ₁ to reduce the diameter. It is known that a diameter-reduced portion 106 composed of a tapered portion 104 and a neck portion 105 is formed by spinning while being moved in the X ₁ -X ₁ direction. ing.

[0003]

The above-mentioned FIG.
In addition to a tube in which a raw tube portion (diameter portion) of the work 100 and a reduced diameter portion 106 are formed with X ₁ -X ₁ being coaxial as shown in FIG. 13, a raw tube portion 201 of a work 200 as shown in FIG. There is a demand for a pipe or a container in which the axis X ₂ -X ₂ and the axis X ₃ -X ₃ of the tapered portion 202 and the neck 203 are eccentric (offset) by a predetermined amount OF.

For example, when used as an outer tube of a muffler for an automobile, its mountability is improved, and when used as a container of an exhaust gas purifying device, the mountability is improved to bring the container closer to the engine side to reduce the catalyst temperature. Helps to reduce the climb time.

[0005] However, the conventional method of spinning shown in FIG. 12 cannot form a pipe or a container in which the tapered portion 202 or the neck 203 is eccentric as shown in FIG.

Therefore, conventionally, in manufacturing such eccentric tubes and containers, the tapered portion 202 and the neck portion 203 are formed separately from the base tube portion 201 by press working to form a plurality of press-formed bodies. Is used in combination. However, according to such a construction method, since different operations are required, the production is difficult, the production cost is increased, and the strength as high as the integral molding cannot be expected. Therefore, a method of integrally and easily forming the eccentric tube or container shown in FIG. 13 is desired.

Accordingly, an object of the present invention is to provide a method and apparatus for forming a pipe end satisfying such a craving.

[0008]

According to a first aspect of the present invention, there is provided a work holding means for holding a work made of a metal tube, and a rotating means for rotating the work holding means. The center of the workpiece holding means is decentered from the axis of rotation of the rotating part, and the workpiece is revolved around the rotating axis of the rotating part. Forming a reduced-diameter portion on a workpiece.

According to a second aspect of the present invention, in the first aspect, the spinning is performed by moving the work holding means in a radial direction from the rotation axis of the rotating portion in multiple stages. A method for forming a pipe end, characterized in that:

According to a third aspect of the present invention, in the first aspect, the spinning is performed while the work holding means is continuously moved in a radial direction from a rotation axis of the rotating portion. A method for forming a pipe end, characterized in that:

According to a fourth aspect of the present invention, there is provided an apparatus used in the method for forming a pipe end, comprising: a rotating portion; and a work holding means for holding the work in parallel with a rotation axis of the rotating portion. Eccentric means for transmitting the rotation of the rotating part to the work holding means and moving the work holding means eccentrically with respect to the rotation axis of the rotating part, and pressing against the end of the work held by the work holding means. And a roller.

According to a fifth aspect of the present invention, in the fourth aspect of the present invention, the eccentric means is provided with a pipe end which is configured to be able to move an eccentric amount by an arbitrary amount and to fix the moving position. It is a molding device.

According to a sixth aspect of the present invention, in the fourth aspect, the arbitrary amount of eccentric movement and fixation can be performed during rotation of the work holding means. This is a device for forming a pipe end.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the embodiments shown in FIGS.

FIG. 1 is a longitudinal sectional view of a molding apparatus according to the present invention, and FIG.
Is a sectional view taken along line AA in FIG. 1, and FIG. 3 is a plan sectional view of FIG. A main shaft rotating unit 3 is fixedly provided on a base 1 and has a main shaft rotating unit 3 horizontally penetrated therethrough, and is rotatably supported by a main bearing 4. and rotates around the core X _4. The spindle rotating unit 3 is appropriately rotated by a rotation driving means. In the embodiment shown in the figure, a pulley 5 is provided at the rear of the spindle rotating unit 3 and is rotated by a driving motor 6. . Further, a flange portion 3a is integrally formed at a front portion of the spindle rotating portion 3.

A guide member 8 constituting the eccentric means 7 is fixed to the flange 3a. On the front side of the guide member 8, the direction of the guide surface 9 across the axis X ₄ of the spindle rotation part 3 located on both sides perpendicular to the axis X ₄ are formed two parallel. A guide piece 12 of a T-slot 11 is slidably provided in a recess 10 forming the guide surface 9.

[0017] The T-slot 11, as shown in FIG. 4, at the center thereof, said forming a hole 13 parallel to the axis X ₄ of the spindle rotation part 3, guide rectangular as viewed in the rear in the axial direction The piece 12 is formed up and down, and a disk-shaped flange 14 is integrally formed at the front part. With such a configuration, the T-slot 11 is arranged along the guide surface 9 so that the axis X ₄
From the radial direction.

A holding plate 15 for slidably guiding and holding the T slot 11 is fixed to the guide member 8. Further, an annular body 16 is fixed to the outer periphery of the guide member 8 and the holding plate 15.

The T-slot 11 has a ball screw 17
Are screwed in a penetrating state in parallel with the guide surface 9, and the T-slot 1 is rotated by forward and reverse rotation of the ball screw 17.
2 reciprocates in the left-right direction in FIG. 2, that is, in the radial direction from the rotation axis X ₄ , so that the axis X ₅ of the T-slot 11 coincides with the axis X ₄ of the main spindle rotating unit 3, It can be made eccentric (offset).

Both ends of the ball screw 17 are rotatably supported by the annular body 16. Further, the ball screw 17
A motor 18 serving as a rotation driving means provided on the annular body 16
The rotation is made forward and reverse. The motor 18
The forward and reverse rotation amount is controlled by numerical control, and the forward and reverse rotation amount of the ball screw 17 is controlled to control the reciprocating movement amount of the T slot 11.

A slip ring 19 for supplying power and a control signal to a motor 18 is fixed to the outer periphery of the annular body 16. Further, a brush 20 for supplying power and a control signal to the motor 18 is in contact with the slip ring 19. In addition, the rotation of the main shaft rotating unit 3 causes the motor 18 to rotate due to the centrifugal force acting on the T slot 11.
A disc brake 21 for canceling the rotational force acting on the motor 18 is provided so that the rotation of the motor 18 can be locked.

A work holding means 22 is fixedly provided on the flange 14 of the T slot 11. The work holding means 22 includes an openable and closable chuck 24 having a work insertion hole 23 formed in the center thereof, and a mechanism for driving the chuck 24 to open and close. The work holding means 22 may be fixed to the T slot 11 using a commercially available chuck mechanism. The opening and closing of the chuck 24, that is, the clamping and unclamping may be performed manually, or may be externally controlled by using a well-known automatic mechanism using electric power, hydraulic pressure, pneumatic pressure, or the like.

The work insertion hole 23 is formed so that its axis is coaxial with the axis of the T-slot 11. When the work W is inserted into the work insertion hole 23 and held by the chuck 24, The axis X ₅ of the work W is coaxial with the axis of the T slot 11.

Therefore, when the T-slot 11 is moved by the rotation of the ball screw 17, the axis X
₅ is adapted to eccentricity in the radial direction in a parallel state with respect to the rotation axis X ₄ of the main spindle rotating part 3.

A spinning roller 25 is disposed in front of the work holding means 22. The spinning roller 25 is rotatably (rotated) provided on a bracket 26. The bracket 26 is driven by driving means (not shown).
Rear direction B along the axis X ₄ of the spindle rotation part 3, D to C and orthogonal, and moved in the E direction, the spinning rollers 25 with the movement of the bracket 26 B,
It moves in the C direction and the D and E directions.

Next, the forming direction of the pipe end will be described. First, the case where the pipe end is eccentrically processed by one spinning process will be described.

As shown in FIGS. 1 to 3, T slot 1
In a state where the axis X _{5 of} the first work piece, that is, the axis of the work insertion hole 23 of the chuck 24 in the work holding means 22 is aligned with the axis X ₄ of the main spindle rotating section 3, the work (base tube) is inserted into the work insertion hole 23. ) W is inserted, the chuck 24 is closed, and the work W is clamped. In this state, the amount of eccentricity (offset) in which the axis X ₅ of the work W matches the axis X ₄ of the main shaft rotating unit 3 is zero.

Next, the motor 18 is rotated to rotate the ball screw 17 by a predetermined amount by numerical control.
The slot 11 is moved in the radial direction from the axis X ₄ along the guide surface 9 by a predetermined amount, the rotation of the motor 18 is stopped at a predetermined position, and the stop position is locked by the disk brake 21.

As a result, as shown in FIGS.
The work holding means 22 fixed to the T slot 11 also moves by the same amount in the same direction as described above, and the axis X _{5 of the} clamped work W is moved a predetermined distance OF from the rotation axis X ₄ of the main spindle rotating unit 3.
Fixed in a state separated only in parallel, that is, in an eccentric (offset) state.

After that, the drive motor 6 is rotated to rotate the spindle rotating unit 3. Accordingly, the workpiece W, as shown in FIG. 8, revolves around the rotational axis X ₄ of the spindle rotation part 3 in one direction H.

In the revolving state of the work W, the spinning roller 25 is driven by driving means (not shown) as shown in FIG.
7, the workpiece W is advanced to the diameter reduction start point F of the work W. From this diameter reduction start point F, the movement of the spinning roller 25 in the centripetal direction E and the retreating direction C is linked, and the arrow in FIG. The trajectory G shown is moved. Accordingly, the spinning roller 25 is pressed against the outer periphery of the revolving work W, and the spinning roller 25 moves in the pressed state, so that the end of the work W is tapered and the tapered portion W ₁ neck W ₂ which is eccentric relative to the axis X ₅ of earlier work W is formed.

FIG. 9 shows a tube formed by such diameter reduction processing. In FIG. 9, W ₁ is the tapered portion, W
Reference numeral ₂ denotes the neck. Incidentally, the eccentricity amount of the neck portion W ₂ of said rotation axis X ₄ of axis X ₅ and the main shaft rotation portion 3 of the workpiece W
And the diameter of the tapered portion W ₁ and the diameter of the neck portion W ₂ can be controlled by the path G of the spinning roller 25.
Can be managed by

As described above, when the eccentricity is achieved by one spinning process, the characteristic ridge line W shown in FIG.
With ₃ is formed, an opening-side end face of the neck portion W ₂ in FIG. 1
It is formed obliquely as shown as W ₄ 0. The diagonal portion is appropriately cut off.

The work W may be inserted and set with the work holding means 22 eccentric (offset) as shown in FIGS. Next, a case where eccentric spinning is performed in multiple stages will be described.

[0035] In this case also, the same rotation of the main shaft rotation portion 3 with the axis X ₅ of the workpiece holding means 22 by eccentric relative to the rotational axis X ₄ of the spindle rotation part 3 is offset the workpiece W To revolve the work W and move the spinning roller 25 in the centripetal direction and the axial direction to reduce the diameter of the work W by eccentricity. , And the movement of the spinning roller 25 is performed in multiple stages in synchronization with the multi-stage movement of the workpiece W.
The diameter reduction ratio with respect to the diameter of the base tube is gradually increased.

By this multi-step processing, the overall shape of the final tapered portion is substantially the same as the tapered shape of the one-time eccentric processing, and the same neck is formed. The tapered shape in the middle of the tapered portion is different from the above-mentioned processing.

That is, the ridge line W shown in FIG._ThreeAppears
Instead, the tapered portion W as shown in FIG. ₁Multi-stage trace of diameter reduction
W_FiveRemains. This diameter trace W_FiveReduces the amount of eccentricity at one time
Increase the number of steps and reduce
Trace W_FiveBecomes inconspicuous. In addition, once at the pipe end
As in the case of the eccentric movement of_FourIs formed,
This oblique part W_FourThe degree of inclination of the eccentric movement
Smaller than the case. This oblique part W_FourExcise as appropriate
You.

Next, a case where the spinning process is continuously performed will be described. This processing is a method in which the multi-step processing is made continuous. The work W is set from the state of FIG. 1 where the work W is set with the axis X ₅ of the work holding means 22 coinciding with the axis X ₄ of the spindle rotating unit 3. The spinning roller 25 is moved in the centripetal direction and the axial direction while W is revolving and eccentrically moving, so that the workpiece W is continuously reduced in diameter. As a result, a taper portion and a neck portion are formed.
As shown in 1 (a) and (b), the tapered portion W ₁ is smooth and ideal shape is less oblique portion W ₄ of the end of the neck portion W ₂ as described above is obtained.

During the spinning process,
An arbitrary diameter can be reduced by offsetting the work holding means 22 by an arbitrary amount at an arbitrary timing.

[0040]

As described above, according to the first aspect of the present invention, the spinning is performed while the work is eccentric and revolved, so that the work body and the work main body are positioned at the end of the work. The cored tapered portion and the reduced diameter portion of the neck can be formed in a continuous state. Therefore, the manufacturing operation is easier and the manufacturing cost can be reduced as compared with the conventional method in which a plurality of press-formed bodies are combined and welded, and the strength can be increased by integrally forming the product. .

According to the second aspect of the present invention, the processing step can be subdivided into a plurality of steps and the processing can be performed little by little. According to the third aspect of the invention, the reduced diameter portion can be formed smoothly.

According to the fourth aspect of the present invention, it is possible to provide an apparatus which can be used in the molding method according to the first aspect. According to the fifth aspect of the present invention, it is possible to provide an apparatus that can be used in the molding method according to the second aspect.

According to the sixth aspect of the present invention, the amount of eccentricity can be continuously increased during one diameter reduction process, so that a product in which the reduced diameter portion is continuously deformed into a smooth tapered shape can be provided. .

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a molding apparatus according to the present invention, showing a state in which the axis of a work coincides with the axis of a rotating unit.

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is a plan sectional view in FIG. 1;

FIG. 4 is a perspective view of a T slot in FIG. 1;

FIG. 5 is a longitudinal sectional view of the apparatus of FIG. 1, in which the axis of the work is eccentric with respect to the axis of the rotating unit.

FIG. 6 is a sectional view taken along line AA in FIG. 5;

FIG. 7 is a plan sectional view in FIG. 5;

FIG. 8 is a diagram showing a revolving locus of a work according to the present invention.

FIG. 9 shows a product formed according to the present invention;
(A) is a perspective view, (b) is a side view, (c) is a cross-sectional view taken along line II in (a), and (d) is a cross-sectional view taken along line JJ in (a).

FIG. 10 is a side view showing a product manufactured by multi-stage eccentric processing in the present invention.

11A and 11B are side views showing two examples of a product manufactured by continuous eccentricity processing in the present invention.

FIG. 12 is a longitudinal sectional view showing a conventional end tube forming apparatus.

FIG. 13 is a side sectional view of a work showing a reduced diameter portion to be formed according to the present invention.

[Explanation of symbols]

 W Work 3 Rotating part 7 Eccentric means 11 T slot 17 Ball screw 18 Motor 22 Work holding means 25 Roller

Claims (6)

[Claims] A work holding means for holding a work made of a metal tube, and a rotating part for rotating the work holding means, wherein the work holding means is eccentric in its axis relative to the rotation axis of the rotating part. A roller is pressed against the outer periphery of the end of the work while rotating around the rotation axis of the rotating portion, and spinning is performed to form a reduced diameter portion in the work. 2. The method according to claim 1, wherein the spinning is performed by moving the work holding means in a radial direction from the rotation axis of the rotating portion in multiple stages. 3. The method according to claim 1, wherein said spinning is performed while continuously moving said work holding means in a radial direction from a rotation axis of said rotating part. 4. A rotating part, a work holding means for holding a work in parallel with a rotation axis of the rotating part, and transmitting the rotation of the rotating part to the work holding means and connecting the work holding means to the rotating part. An apparatus for forming a pipe end, comprising: an eccentric means for eccentrically moving with respect to a rotation axis; and a roller for pressing against an end of a work held by a work holding means. 5. The apparatus according to claim 4, wherein said eccentric means is configured to be able to move an eccentric amount by an arbitrary amount and to fix its moving position. 6. An apparatus according to claim 4, wherein said arbitrary amount of eccentric movement and fixation can be performed during rotation of the work holding means.