KR20150026823A - A forging swing press - Google Patents

Abstract

Provided is a swing press for forging capable of remarkably reducing a forming load. A press includes an eccentric shaft (8) mounted on a press frame (1) to be rotatable; a cone rod (11) lifted by being connected to the eccentric shaft (8); and a bed (2) carrying a lower mold (36), wherein an oscillation guide adding an oscillating motion to the lifting motion of the cone rod (11) is disposed, the lower surface of an upper mold (16) mounted on the lower surface of the cone rod (11) forms a curved surface progressively becoming convex downward, and the curved surface changes along the direction of the oscillating motion. The cone rod (11) oscillates by the oscillation guide while being lifted in accordance with the rotation of the eccentric shaft (8), such that the upper mold (16) mounted on the lower surface of the cone rod (11) also oscillates to come in contact with and press the lower mold (36) from one end portion to the other end portion in order. The forming partially occurs from one end portion to the other end portion of the upper mold (16), thereby requiring small pressing force, and being sufficient if a driving source is small.

Description

[0001] A forging swing press [0002]

The present application claims priority based on Japanese Patent Application No. 2013-181407 filed on September 2, 2013. The entire contents of which are incorporated herein by reference.

The present invention relates to a swing press for forging. More particularly, the present invention relates to a new forging press of the type in which a metal mold is pivoted when a metallic material is compressed or struck by using a top and bottom mold to be formed into an arbitrary shape.

In a conventional mechanical press for forging, as shown in Non-Patent Document 1, an eccentric shaft is rotatably mounted on an upper portion of a press frame, an upper end of the con rod is mounted on an eccentric shaft, And the rotational motion of the eccentric shaft given by the driving source is converted into the reciprocating motion of the slide. Further, the slide is guided by the gib mounted on the frame to satisfy the straightness of the reciprocating movement of the slide.

The upper mold is mounted on the lower surface of the slide converted to the reciprocating motion, and the upper mold is pressed by the upper and lower molds so as to approach the lower mold fixed on the bed.

The above structure is conventional, and in these conventional mechanical presses for forging, the upper mold is characterized in that the lower surface of the upper mold is lowered while maintaining its level. In this molding process, the upper and lower die sizes gradually become smaller over the entire width of the metal mold, and the load rises sharply as the bottom dead center becomes closer to the maximum at the bottom dead center. When the entire surface of the upper and lower molds is pressed uniformly in this manner, the load becomes larger than when the mold is pressed to a part of the mold.

It is necessary to select a press facility having a nominal capacity equal to or higher than the maximum load occurring at the bottom dead center, and to use large facilities in response to a large load.

In recent years, a press driven by a servo motor has been developed. However, since a hot forging press requires high-speed forming, a large motor torque is required.

As a result of intensive investigation under the theme of reduction in press load, the present inventors have found that, by forging the upper mold to partially pressurize the upper and lower molds and to continuously displace them, the forging is gradually molded to reduce the load required for forging I found that I could.

[0004] As a press for rocking the slide, there is a conventional technique disclosed in Patent Document 1. [0005] This prior art is for the purpose of causing a single crankshaft to perform a plurality of slide operations with different bottom dead center positions and motions.

The structure is such that a con rod connected to the eccentric portion of the crank shaft and each plunger type slide slidably fitted to a plurality of plunger guides arranged in parallel are linked by a link so that the lower end of the con rod is rotated And is fitted in a corresponding shape bearing member for guiding the lower end portion of the lower end portion to be rotatable about the center of rotation.

However, in this conventional technique, the slide is pivoted, but the upper mold itself does not rock, and the upper mold descends to the bottom dead center in a parallel posture with respect to the lower mold and presses down.

Therefore, it is not the same as a conventional mechanical press in that it presses the entire surface of the metal mold, so that the problem of a large press load can not be solved.

Prior art literature

(Patent Literature)

Patent Document 1: JP-A-6-55295

(Non-patent document)

Non-Patent Document 1: Plastic Forming Series "Forging" 321-326 First Edition, August 30, 1995 CORONA PUBLISHING CO., LTD.

In view of the above circumstances, the present invention has been completed on the basis of a completely new idea based on the results of intensive study of the present inventors, and it is an object of the present invention to provide a forging swing press capable of greatly reducing a forming load.

A swing press for forging according to a first aspect of the present invention includes an eccentric shaft rotatably mounted on a press frame, a con rod having one end connected to the eccentric shaft and reciprocating in a predetermined direction by rotation of the eccentric shaft, And a swinging guide for swinging the reciprocating motion of the con rod, wherein the second mold is mounted on the other end side of the con rod, and the surface of the second mold Or the surface of the first mold has a curved surface that is convex toward the counter metal mold, and the curved surface changes along the direction of the swing motion.

In the forging swing press of the second invention, in the first invention, the swing guide rotatably supports the other end side of the con rod, and reciprocating motion in the predetermined direction in accordance with the reciprocating motion of the con rod And a guide portion extending in the predetermined direction provided in the press frame, and the guide portion guides the reciprocating operation in the predetermined direction of the guided body.

In the forging swing press of the third invention, in the first or second invention, the second mold is mounted on the other end side of the con rod so as to face the first mold, and the parting of the second mold And the line coincides with the center of rotation of the other end of the con rod.

The forging swing press of the fourth invention is characterized in that, in the first, second or third invention, the driving source of the eccentric shaft is a servo motor.

The forging swing press according to the fifth aspect of the present invention is the swing press according to the fourth aspect of the present invention, further comprising a control device for controlling the drive source, wherein the control device controls the second mold so that, And an on-off control section for controlling the on-off control from the over-position to maintain the on-control until the forming of the second mold is finished beyond the bottom dead center.

The swing press for forging according to the sixth aspect of the present invention is the swing press for forging according to the fourth aspect of the present invention, further comprising a control device for controlling the driving source of the eccentric shaft, And a rotation angle control unit for rotating the rotation of the eccentric shaft at a low speed.

The swing press for forging according to a seventh aspect of the present invention is the swing press according to the fourth aspect of the present invention, which comprises a shut height adjusting mechanism for adjusting a shut height and a control device for controlling the driving source of the eccentric shaft, Stop control of the eccentric shaft.

The forging swing press of the eighth invention is characterized in that the swing press of the eighth invention is provided with a rotating mechanism for rotating the first mold on a plane perpendicular to a predetermined direction on the fixed portion.

According to the first aspect of the present invention, since the con rod is moved up and down by the swing guide in accordance with the rotation of the eccentric shaft, the upper mold attached to the lower surface of the con rod is also pressed against the lower mold sequentially from one end toward the other end. At this time, since the lower surface of the upper mold (or the upper surface of the lower mold) has a convex curved surface (or a convex curved surface), the pressing force with respect to the material on the lower mold in the regions before and after the bottom dead center of the upper mold, So that the same pressing effect as that of forging using an ordinary metal mold can be obtained. Further, since the molding proceeds sequentially from one end of the upper and lower molds to the other end, the pressing force may be small, and it is sufficient that the driving source is small.

The concept of the first invention, in which the upper and lower molds do not mold at once but progresses slowly, is innovative, and furthermore, miniaturization and cost reduction of the press obtained thereby are remarkable.

According to the second aspect of the present invention, the guide portion provided in the press frame guides the guided body mounted on the lower end of the con rod. At this time, since the guided body is guided to ascend and descend, the coned rod ascends and descends in accordance with the rotation of the eccentric shaft, and at the same time, the lower end of the coned rod oscillates. As a result, the upper mold can be forged while being in contact with the lower mold sequentially from the one end toward the other end.

According to the third invention, since the parting line of the upper mold coincides with the rotation center of the guided body, the movement of the upper mold also causes the up-down motion and the swing motion relative to the rotation center of the guided body, It is possible to substantially eliminate the positional shift in the forward and backward directions with respect to the molding position of the mold.

According to the first invention, since the forming load becomes small, it is possible to use a servo motor having no large output as a driving source. Therefore, by using the servo motor as in the fourth invention, it is possible to exhibit high controllability, to change the on / off point of the power source, to enable low-speed switching, and to enable repetition of normal and reverse operation. As a result, a mechanical press for forgings excellent in controllability can be obtained.

According to the fifth invention, it is possible to apply pressure not only from the bottom dead center of the upper mold to just under the bottom dead center but also by applying a driving force from immediately below the bottom dead center to thereafter. The pressurizing force can be applied to both of the pressing process of the pressurizing process of the pressurizing process.

According to the sixth aspect of the present invention, in the region where the acceleration of the con rod is large, the con rod swings at a high angular speed, so that it is easy to scatter the lubricant largely. However, if the rotation in this region is made low, easy to do.

According to the seventh aspect of the invention, the eccentric shaft is electrostatically charged, the material on the lower mold is successively brought into contact with the other end of the upper mold from the one end to the other end to reduce the shut height once the eccentric shaft is stopped, A series of molding operations for pressing the material on the lower mold sequentially from the other end of the upper mold toward one end can be repeated. By performing such repeated molding, the material can be forged to a desired shape while reducing the load.

According to the eighth aspect of the present invention, when the material of the lower mold is once pressed and then the lower mold is rotated in the horizontal plane by the rotation mechanism, portions which could not be initially pressed can be pressed. Therefore, even if the material is wider than the upper and lower molds, the mold can be forged.

1 is a front view of a forging swing press according to an embodiment of the present invention.
2 is a sectional view taken along the line II-II in Fig.
3 is a sectional view taken along line III-III in Fig.
4, (a) is a plan view of the con rod, and (b) is a front elevational view.
5 (a) is a side view of the con rod, and Fig. 5 (b) is a sectional view taken along the line VV in Fig.
In Fig. 6, (a) and (b) are explanatory views of the swing motion of the con rod.
Fig. 7 is an explanatory view of an operating state during the time when the conoid and the upper mold arrive after the bottom dead center.
Fig. 8 is an explanatory view of the swing motion from when the con rod and the upper mold reach the bottom dead center before the bottom dead center.
9 is an explanatory diagram of an upper mold and a lower mold according to an embodiment.
10 is an explanatory diagram of an upper mold and a lower mold according to another embodiment.
11 is an explanatory diagram of an embodiment in which the lower mold 36 is rotated.

Next, an embodiment of the present invention will be described with reference to the drawings.

1 and 2, the basic structure of a forging press P for forging will be described first.

Reference numeral 1 denotes a press frame, which comprises a lower bed 2, a crown 3 above the column, and four columns 4 connecting the crown 3 and the lower column.

In each column 4, a tie rod 5 passes, whereby the bed 2 and the crown 3 are tightly fastened. The side frames 6 are fixed between the front and rear columns 4 and 4 on the left side and the side frames 6 are also mounted between the front and rear columns 4 and 4 on the right side.

As shown in Figs. 1 and 3, in the upper portion of the left and right side frames 6, 6, a hole is formed in which the bush 7 is inserted, and an eccentric shaft 8 is rotatably inserted in the hole . The eccentric shaft 8 shown in the drawing is a well-known structure composed of an eccentric portion 8a at the center portion and shaft portions 8b and 8b at both sides thereof.

The eccentric shaft 8 is connected at its end to a motor 9 serving as a driving source. A variety of motors can be used without limitation, but it is preferable to use a servomotor with good controllability. When the servomotor 9 is used, a control device 10 composed of a computer or the like is connected thereto.

A coned rod 11 is connected to the eccentric portion 8a of the eccentric shaft 8. Unlike the conventional press structure, the present invention does not have a slide used in a conventional forging press. And is characterized in that a specific structure is given to the coned rod 11 without using a slide.

First, the structure of the coned rod 11 itself will be described with reference to Figs. 4 and 5. Fig.

The coned rod 11 has a structure in which two right and left vertical blocks 12 and 12 are connected by a horizontal block 13 at a longitudinally central portion.

Holes 14 and 14 passing through the eccentric portion 8a of the eccentric shaft 8 are formed on the upper portions of the left and right vertical blocks 12 and 12, respectively.

An upper mold 16 (corresponding to a second mold in the claims) is provided on the lower surface of the right and left vertical blocks 12 and 12, specifically, on the lower surface of the horizontal block 13, through a mold holder 15 Respectively.

Next, a swing guide for swinging the con rod 11 will be described.

The rocking guide is composed of the guided body 20 on the side of the con rod 11 and the guide groove 25 on the press frame side (see Figs. 1 to 3).

On the outer surfaces of the lower ends of the left and right vertical blocks 12, 12, guided bodies 20 are respectively provided. This guided body 20 is constituted by a guide block 21 which is a rectangular body and a bearing 22 sandwiched between the centers of the guide block 21.

A support shaft 23 protruding outward is formed at the lower ends of the left and right vertical blocks 12 and 12. A bearing 22 of the to-be-guided body 20 is rotatably supported on the support shaft 23 Respectively.

As shown in Fig. 3, a guide groove 25 is formed inside the lower portion of the side frame 6 so as to extend in the vertical direction. 2, the guide groove 25 is formed at a central position in the width direction (longitudinal direction) of the side frame 6. As shown in Fig. In other words, the axial center position of the eccentric shaft 8 and the center of the guide groove 25 coincide with each other in the forward and backward directions of the press (up and down directions of the paper surface in Fig. 2). However, in the present invention, the " guide portion " in the claims is not limited to the guide groove as in the present embodiment, and any other guide mechanism can be used.

The guided body (20) is fitted in the guide groove (25) and is slidable up and down. Therefore, when the con rod 11 is lifted and lowered in accordance with the rotation of the eccentric shaft 8, the guided body 20 at the lower end is raised and lowered without being eccentric. However, the rotational motion of the upper portion of the coned rod 11 accompanying the rotation of the eccentric shaft 8 is absorbed by the bearing 22.

As shown in Fig. 1, a mold holder 35 is provided on the upper surface of the bed 2, and a lower mold 36 (corresponding to a second mold described in the claims) is mounted on the upper surface thereof.

1 is a state in which the upper mold 16 is lowered to the bottom dead center position. In this state, the lower surface of the upper mold 16 and the upper surface of the lower mold 36 are closest to each other, and the lower surface of the upper mold 16 in this state is divided into a parting line L16 for dividing the upper and lower molds, Respectively.

The parting line L16 coincides with the axial center of the guided body 20. However, there is no exact match or there may be some deviation. However, its advantages will be described later.

6 (a) and 6 (b) show the operation of lifting and swinging the coned rod 11 as the eccentric shaft 8 rotates.

6 (a), since the eccentric portion 8b of the eccentric shaft 8 is directly below, the coned rod 11 is at the lowest position. That is, the upper mold 16 becomes the bottom dead center position.

6B shows a state in which the eccentric portion 8b of the eccentric shaft 8 is rotated counterclockwise by 270 DEG from the top dead center position. At this time, the upper portion of the con rod 11 moves to the left, but the lower guided body 20 is fitted in the guide groove 25 of the press frame (side frame 6) . As a result, the coned rod 11 is inclined as a whole to the left.

When the eccentric portion 8b of the eccentric shaft 8 rotates in a direction opposite to that shown in Figure 6 (b) (i.e., counterclockwise from the bottom dead center), the coned rod 11 as a whole has an upper- Lt; / RTI >

The above operation means that the lower surface of the con rod 11 swings like a seesaw. During this operation, the guide block 21 ascends and descends in the guide groove 25, and the bearing 22 allows the cone rod 11 to tilt (rocking motion).

In Fig. 7, I represents the position of 30 deg. Before the bottom dead center of the upper mold 16, II represents 10 deg. From the bottom dead center, III represents the bottom dead center position, IV represents 10 deg. After the bottom dead center, Indicates the position of 30 degrees after the bottom dead center.

When the eccentric shaft 8 rotates in the counterclockwise direction, the con rod 11 is changed in posture from the leftward inclination to the upright and rightward inclination. At this time, the lower surface of the upper mold 16 is inclined to the left in the drawing at the I position, the inclination angle at the II position decreases, horizontally at the III position, and at the IV position, To take a right downward inclined posture. That is, in accordance with the ascending and descending of the con rod 11, the upper mold 16 performs the rocking motion indicated by I to V described above. In addition, the movement trajectory of the lower surface of the upper mold 16 becomes convex curved surface upward.

However, the upward movement path of the guided body 20 is guided by the guide groove 25 even when the swinging is performed in this manner, so that the upper mold 16 does not cause a deviation with respect to the lower mold 36. [

Fig. 8 is an enlarged view of the states I to III in Fig. The swing angle? Of the upper mold 16 necessary for molding is determined according to the ratio of the eccentric amount of the eccentric shaft 8 to the length H of the coned rod 11. The appropriate swing angle is determined by the eccentric amount of the eccentric shaft 8 and the length H of the con rod 11 as shown in FIG. 5, since the proper swing angle at the start of the molding is changed according to the properties, shape, And may be given by selection.

In the case where one material is sequentially processed and molded in one process as in the present invention, the upper and lower molds are brought into contact at one point at each time of molding, and the motion of the con rod near the bottom dead center And upward and downward movement), it is preferable that the upper mold has a geometric shape in which the upper mold is basically continuously contacted with the lower mold throughout the molding region.

In order to obtain such a mold shape, it is preferable that: a) the lower surface of the upper mold is curved downwardly and the upper surface of the lower mold is flat; and b) the upper surface of the upper mold is made flat and the upper surface of the lower mold is curved upward There are two ways of doing this.

Fig. 9 shows the upper mold 16 and the lower mold 36 of the type of a). The position of the upper mold surface when the inclined surface [theta] of the upper mold 16 changes in the range of 30 to 0 degrees is shown.

The lower surface 16f of the upper mold 16 has a downwardly convex curved surface as is clear from a comparison with a flat line L16 connecting both ends of the upper mold 16. The curved surface of the upper mold 16 (From one end) to the right end (the other end) in the drawing. This curved surface is the inverted shape of the locus (see Fig. 7) drawn by the lower surface of the upper mold 16 in the vicinity of the bottom dead center.

The upper surface 36f of the lower mold 36 is finished in a flat, non-curved plane. However, all of the upper and lower molds should be molds that are shaped so that the positions of the upper and lower molds correspond precisely during the swinging motion of the upper mold.

In the present invention, since the molding using the mold proceeds sequentially from one end of the upper and lower molds to the other end during one process, the pressing force may be small. Therefore, it is sufficient that the driving source of the press is small. It is also possible to reduce forging sound.

Since the parting line L16, which is the dividing surface of the upper and lower molds, coincides with the axial center of the guided body 20, the movement of the upper mold also causes the up-and-down motion and the oscillating motion with respect to the rotational center of the guided body, It is possible to substantially eliminate the positional deviation in the front-rear direction with respect to the molding position of the upper surface of the lower mold.

As shown in Fig. 1, the present embodiment includes a control device 10 for controlling the operation of the servo motor 9. As shown in Fig. The control device 10 is constituted by a computer or the like and has an on / off control section 10A, a rotation angle control section 10B and a forward rotation control section 10C have.

The on-off control unit 10A controls the upper mold 16 to turn on at the position exceeding the top dead center, maintains the ON control until the upper mold 16 passes the bottom dead center and the molding is completed, To do. However, the on-off control unit 10A does not control to turn on the upper mold 16 beyond the top dead center, but may control the on-off control before turning on. That is, the on-off control section 10A controls the upper mold 16 from a position exceeding the top dead point at the latest after the molding in the previous cycle is completed.

When the on-off control is performed, the pressing force can be applied not only from the bottom dead center of the upper mold 16 to just under the bottom dead center but also from the bottom dead center to the bottom dead center. The pressing force can be applied to both the first pressing step and the second pressing step, thereby improving the processing efficiency and increasing the forming accuracy.

The rotation angle control section 10B controls the rotation angle of the eccentric shaft 8 in the vicinity of the bottom dead center of the eccentric shaft 8 in a region where the angular velocity of the con rod 11 is large, 8 is rotated at a low speed.

This control of the rotational angle makes it easy to scatter the lubricant oil at a high angular velocity in a region where the angular speed of the con rod 11 is large. The speed at the time of collision can be suppressed and scattering of the lubricating oil can be easily prevented.

In the present embodiment, a shut height adjusting device for adjusting the shut height is provided. The shut-hight adjusting device can be a known one without any limitations. For example, an eccentric sleeve is provided in the journal portion of the eccentric shaft 8, an eccentric sleeve is provided between the eccentric portion 8a of the eccentric shaft 8 and the connecting hole of the con rod 11, A wedge adjusting mechanism may be provided on the ball screw 2 side, a wedge adjusting mechanism may be provided between the ball stud and the lower die 36, and the like.

The present embodiment further includes a forward reverse rotation control section 10C. The forward-reverse control section 10C performs forward-reverse control to control the stopping, stopping, and reversing of the eccentric shaft 8.

When the shut-height adjustment and the forward-reverse control are combined, the eccentric shaft 8 is electrically charged to press the material on the lower mold 36 sequentially from one end of the upper mold 16 to the other end, It is possible to perform a series of molding operations in which the shuttle is made smaller and then the eccentric shaft 8 is reversed to sequentially bring the material on the lower mold 36 into contact with the other end of the upper mold 16 one by one. By repeating such pendulum motion, press forging becomes possible, and by performing such press forging, the material can be forged to a desired shape while reducing the load.

Next, another embodiment of the present invention will be described.

In the above-described embodiment, the mold shape is finished with the lower surface of the upper mold 16 being curved downwardly convexly. In the present embodiment, the mold shape is the type of b). 10, the upper surface 36f of the lower mold 36 is finished in a convex curved surface upward, and changes along the direction of the swing motion of the upper mold 16. As shown in Fig. That is, this curved surface has the same shape as the locus (see Fig. 7) drawn by the lower surface of the upper mold 16 near the bottom dead center, as is clear from comparison with the flat line L36 connecting both ends of the lower mold.

9 shows the position of the upper mold side when the inclination angle [theta] of the upper mold 16 changes in the range of 30 to 0 degrees.

The lower surface 16f of the upper mold 16 is finished in a flat plane. However, all of the upper and lower molds should be molds that are shaped so that the positions of the upper and lower molds correspond precisely during the swinging motion of the upper mold.

Also in this embodiment, as in the above-described embodiment, since the molding proceeds sequentially from one end of the upper and the lower mold toward the other end, the pressing force may be small and the driving source may be small. It is also possible to reduce forging sound.

In the above embodiment, the lower mold 36 is fixed on the bed 2. In this embodiment, as shown in Fig. 11, the lower mold 36 is rotatable on the bed 2 in a horizontal plane.

That is, the lower mold 36 is fixed to the lower mold holder 35 or the appropriate rotating base 37, and the lower mold holder 35 and the rotating base 37 are rotated It is possible.

For example, even when the width W16 of the upper mold 16 is narrower than the width of the forged product, when the rounded fork such as a gear is finished, the uncut portion is machined can do. By repeating this operation several times, it is possible to process a wide forging product using a small-sized metal mold.

1: Press frame
2: Bed
3: Crown
6: Side frame
8: Eccentric shaft
9: Servo motor
10: Control device
11: Con rod
16: Upper mold
20:
25: Guide groove
36: Lower mold

Claims (8)

A press machine comprising: an eccentric shaft rotatably mounted on a press frame; a con rod having one end connected to the eccentric shaft and reciprocating in a predetermined direction by rotation of the eccentric shaft; and a fixture for fixing the first mold ,
And a swinging guide for swinging the reciprocating motion of the con rod,
A second mold is mounted on the other end side of the con rod,
Wherein the surface of the second metal mold or the surface of the first metal mold has a curved surface that is convex toward the counter metal mold and the curved surface changes along the direction of the rocking motion. The method according to claim 1,
Wherein,
A guided body rotatably supporting the other end side of the con rod and reciprocating in the predetermined direction in accordance with the reciprocating movement of the con rod,
And a guide portion provided in the press frame and extending in the predetermined direction,
Wherein the guide portion guides the reciprocating movement in the predetermined direction of the to-be-guided body. 3. The method according to claim 1 or 2,
The second mold is mounted on the other end side of the con rod so as to be opposed to the first mold,
And the parting line of the second mold coincides with the center of rotation of the other end side of the coned rod. 3. The method according to claim 1 or 2,
Wherein the driving source of the eccentric shaft is a servo motor. 5. The method of claim 4,
And a control device for controlling the driving source,
The control unit controls to turn on the second mold at a position beyond the top dead point at the latest after the molding in the previous cycle is completed and maintains the on control until the molding of the second mold exceeds the bottom dead center And an on-off control unit for performing an off control subsequently. 5. The method of claim 4,
And a control device for controlling the driving source of the eccentric shaft,
Wherein the control device includes a rotation angle control section for rotating the rotation of the eccentric shaft at a low speed in a region where the angular speed of the con rod is large other than the vicinity of the bottom dead center of the eccentric shaft. 5. The method of claim 4,
A shut height adjusting mechanism for adjusting a shut height and a control device for controlling a driving source of the eccentric shaft,
Wherein the control device is a forward-reverse-rotation control section for controlling the electric power stopping, stopping, and reversing of the eccentric shaft. The method according to claim 1,
And a rotating mechanism for rotating the first mold on a plane perpendicular to a predetermined direction on the fixed portion.

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