JP2010179365A - Buckling prevention structure for flange forming machine of tubular material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a buckling prevention structure which prevents a tubular material from buckling inside during flange forming of the tubular material. <P>SOLUTION: In the flange forming machine, an end part of the tubular material is expanded and bent to a low angle of 60° or less by a primary roller with a conical shape having its rotation axis inclined to the revolution central axis, and then bent to about 90° by a secondary roller with the conical shape having its rotation axis inclined to the revolution central axis. The flange forming machine is characterized in that the primary roller has the primary roller body with a trapezoidal conical shape contracting toward its top and a buckling prevention roller having an inverted conical part attached on the top of the body. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a buckling prevention machine for preventing a buckling from occurring on the inside of a pipe material in a bristle forming machine used for bridging and forming an end portion of a metal pipe material.

The end of the tube is expanded and bent at a low angle of 60 ° or less with a conical primary roller having a rotation axis inclined toward the revolution center axis, and then the rotation axis inclined toward the revolution center axis In the tubular material forming machine that bends at about 90 ° by the conical secondary roller, buckling defects are likely to occur inside the joint between the collar and the tube body.
Up to now, it is considered that buckling occurs in a bending process of about 90 ° for a secondary roller, and the present applicant has proposed a technique shown in Patent Document 1.
However, a detailed investigation and study of the true cause of the tube material buckling inward during the rib forming revealed that the cause of the buckling lies in the low-angle widening bending process by the primary roller.
The contents will be described with reference to FIG.
When the tube 1 is clamped and the end 1a is expanded and bent at about 40 ° by the primary roller 230, the disk-shaped cored bar 150 is inserted, but the tip 230a of the primary roller 230 and the cored bar 150 are Since a small gap d is formed between them, it has been clarified that a buckling starting point 1b is generated so as to enter the gap, and as a result, a large buckling is caused in a bending process of about 90 ° by the secondary roller.
This is because the tip of the primary roller 230 needs to enter the inside of the tube in order for the primary roller 230 to expand and bend the end of the tube by revolving and rotating, but the core metal interferes at that time. This is because the gap d is necessary to avoid the problem.
In addition, in order to avoid interference with the tip of the primary roller, a spring may be provided on the tip of the core so that the core is retracted in the S direction. When the gap occurs, the gap d is the cause.

JP 2003-39118 A

  An object of this invention is to provide the buckling prevention structure which prevents that a pipe material buckles inside at the time of pipe forming of a pipe material.

In the buckling prevention structure according to claim 1, the end of the tube material is expanded and bent at a low angle of 60 ° or less with a conical primary roller having a rotation axis inclined toward the revolution center axis. In the tube forming machine for tube material which is bent at about 90 ° by a conical secondary roller having a rotation axis inclined toward the revolution center axis, the primary roller has a truncated cone shape with a reduced diameter at the tip side. It has the following roller main-body part and the buckling prevention roller which has the reverse cone part attached to the front-end | tip of the said main-body part, It is characterized by the above-mentioned.
Here, since the primary roller and the secondary roller have the rotation shaft inclined toward the revolution center axis, the primary roller and the secondary roller rotate while revolving around the revolution center axis. .
In the present invention, the primary roller is rotatably attached to a support column supporting the primary roller, and the rotation axis center of the primary roller is eccentric inward with respect to the revolving track of the revolving support column center. You may attach freely.
With such a structure, when the primary roller is advanced to the inside of the pipe, the primary roller is rotatable with respect to the support column and the primary roller mounting rotation shaft is deviated inward and outward from the center of the support column on which the primary roller revolves. Therefore, the primary roller is pushed by the inner wall of the pipe material and revolves while maintaining an eccentric state so that the rotation shaft is at the innermost side.
Accordingly, it is possible to cope with the tube material having a diameter smaller than the tube diameter that can be accommodated when the rotation shaft of the primary roller is attached to the center of the column.

  In the buckling prevention structure according to claim 3, the end of the tube material is expanded and bent at a low angle of 60 ° or less with a conical primary roller having a rotation axis inclined toward the revolution center axis. In a tubular material forming machine that bends at about 90 ° by a conical secondary roller having a rotation axis inclined toward the revolution center axis, a buckling prevention jig that is inserted inside the tube material, The buckling prevention jig has a disk-like plate to be inserted inside the tube material, and the disk-like plate has an escape groove portion that squeezes the tip of the primary roller.

In the present invention, an anti-conical buckling prevention roller is provided at the tip of the primary roller, or a relief groove portion into which the tip of the primary roller enters is formed in a disk-like plate inserted inside the tube material. It is possible to prevent the buckling starting point from being generated in the low-angle bending process by the secondary roller, and to prevent the tube material from buckling inward when the secondary roller is bent by about 90 ° thereafter.
Further, it is possible to prevent a problem that the pipe material bites inward when the conventional buckling prevention jig is used, and the jig cannot be removed from the inside of the pipe material.
Further, if the primary roller is rotatably mounted so that the center of rotation of the primary roller is decentered inward with respect to the revolving track of the center of the support of the primary roller, the rotation of the primary roller when inserting it into the tube material is performed. Since the shaft is automatically decentered so that the shaft is on the innermost side, tube material with a smaller diameter than before can be pulled out.

The side surface schematic diagram of a bridging molding processing machine is shown. The plane schematic diagram of a bridging molding processing machine is shown. The flow of processing by the primary roller and the secondary roller is shown. The enlarged view of the edge part of a pipe material is shown. The structural example of a buckling prevention jig | tool is shown. The flow of rib forming using a buckling prevention jig is shown. The structural example of a buckling prevention roller is shown. The flow of the bridging forming using the buckling prevention roller is shown. An example in which the rotation axis of the primary roller is eccentric with respect to the center of the column is shown. An example of a conventional buckling prevention jig is shown.

A structural example of the rib forming machine 10 will be described below with reference to the drawings.
1 shows a side view, FIG. 2 shows a plan view, and FIG. 3 (a) shows a state in which the end portion of the pipe material is expanded to about 40 ° and bent outward by a primary roller 30. 3 (b) shows a state where the secondary roller 40 is further bent into a flange shape up to about 90 °.
As shown in FIGS. 1 and 2, an upper clamp 51 and a lower clamp 52 are provided so that an end 1a of a tube material 1 as a workpiece protrudes inward by a predetermined length at one end (right side in FIG. 1) of the processing machine. The base plate 11 is disposed so as to face the clamp means, and four guide rods 14 are provided between the base plate 11 and the clamp means.
It has a first plate 12 on the base plate side and a second plate 13 on the clamping means side that move forward and backward along the four guide rods 14.
The first plate 12 is controlled to move forward and backward by a primary cylinder rod 16 a of a primary cylinder 16 supported by the base plate 11.
The second plate 13 is moved forward and backward by the cylinder rod 17a of the secondary cylinder 17 supported by the first plate.
A rotating gear plate 23 is rotatably attached to the first plate 12, and the rotating gear plate 23 is transmitted through the intermediate gear 22 by the main shaft gear 21 driven by the main shaft motor 20.
The rotating gear plate 23 has a primary roller 30 through a support 31 toward the clamping means side.
The support column 31 is attached through the driven plate 15, and the driven plate 15 is rotatably attached to the second plate 13.
A secondary roller 40 is attached to the driven plate 15 via a support base 41.

Since the primary roller 30 and the secondary roller 40 are eccentric in the direction perpendicular to the axis of the rotary gear plate 23 and are inclined toward the center of the axis, they are revolved by the rotation of the rotary gear plate 23. The primary roller 30 and the secondary roller 31 can rotate about the roller axis.
The driven plate 15 slides along the guide rod 14 and the sub guide rod 18, and the relative position of the primary roller 30 and the secondary roller 31 in the axial direction is changed by the forward and backward movement of the cylinder rod 17 a of the secondary cylinder 17. It is controlled.

Next, the flow of rib forming will be described with reference to FIG.
FIG. 3A shows a step of expanding and bending the collar portion 2 outward by about 40 ° by the primary roller 30, and an enlarged view thereof is shown in FIG.
The primary roller 30 has a substantially conical shape, and revolves and rotates so that the side surface of the cone is expanded from the inside to the outside of the end portion 1 a of the tube material 1.
At this time, it is possible to increase or decrease the magnitude of the bending R of the joint portion between the collar portion and the main pipe by adjusting the advance amount and the sliding contact pressure of the primary roller 30.
Therefore, it becomes possible to set the bending R in accordance with a material having a small elongation, a material that is easily broken, a thickness, and the like, and the versatility of the tapping process is high.

As the next step of expanding and bending the end 1a of the tube material to a low angle of 60 ° or less with the primary roller 30, the second plate 13 is advanced by the secondary cylinder 17.
When the second plate 13 moves forward, the side surface portion of the secondary roller comes into contact with the end portion of the pipe material, and the collar portion is bent by about 90 ° by revolution and rotation to complete the collar portion 2.

FIG. 5 shows an example in which the buckling prevention jig 5 according to the present invention is used for rib forming.
As shown in FIG. 5 (c), the buckling prevention jig 5 connects a shaft 5 c to a disk-shaped disk plate 5 a, and a male scoop part 5 e is formed at the tip of the shaft 5 c to form a column 31 of the primary roller 30. It can be screwed to the attachment part 32 provided in the.
An escape groove 5b into which the tip 30a of the primary roller 30 enters is formed on the outer peripheral portion of the side surface of the disk plate 5a on the primary roller 30 side as shown in an enlarged view in FIG.
The escape groove portion 5b has a ring-like recess shape.
Further, a spring disposition portion 5d may be provided on the inner side of the tube material of the disk plate 5a so as to be retractable in the S direction, thereby preventing interference with the tips of the primary roller and the secondary roller.
In FIG. 5, reference numeral 53 denotes an attachment provided on the clamp side.
Bending is performed so as to press against the attachment 53 when the secondary roller is bent at about 90 °.
The flow of molding is shown in FIG.
Since the buckling prevention jig 5 is attached to the column 31 of the primary roller 30, as shown in FIG. 6A, when the primary roller 30 is advanced, the buckling prevention jig 5 is placed inside the tube material 1. Inserted.
Next, as shown in FIG. 6B, a low-angle bending of about 40 ° is performed, and then the secondary roller 40 is bent to about 90 ° to form the collar portion 2.

FIG. 7 shows an example in which the buckling prevention roller 131 according to the present invention is used for rib forming.
The buckling prevention roller 131 is attached to the tip of a truncated cone-shaped main body portion 130a with a reduced diameter at the tip of the primary roller 130 so as to be able to rotate in alignment with the axial center of the primary roller 130.
The buckling prevention roller 131 has an inverted conical part 131a whose diameter is increased and constrains the inside of the tube material 1. The reverse conical part 131a and the conical side surface 130b of the primary roller main body part 130a are bent at a low angle. Form the bending angle.
The buckling prevention roller 131 and the primary roller main body are attached to each other so as to be freely rotatable, and the circumferential speed of the buckling prevention roller 131 located inside the tube and the circumferential speed of the primary roller in contact with the collar portion. Even if a difference occurs, the buckling prevention roller 131 and the primary roller 130 follow and rotate.
This prevents the scratches on the surface of the pipe material from being generated.
FIG. 8 shows a flow of molding using the primary roller 130 to which such a buckling prevention roller 131 is attached.
As shown in FIG. 8B, the primary roller 130 is expanded and bent at a low angle of about 40 °, and the secondary roller 40 is bent to about 90 ° as shown in FIG. 8C. And the collar part 2 is formed.
Since the primary roller was prevented from generating a buckling start point, the occurrence of buckling inward was eliminated even during processing by the secondary roller 40.

Next, an example in which the primary roller is rotatably attached to the support and the center of the rotation axis of the primary roller is automatically decentered inward with respect to the support center will be described with reference to FIG.
A mounting plate 132 is rotatably mounted to the primary roller column 31 via a bearing 132a or the like.
The primary roller main body 130a is attached to the attachment plate 132 through a height adjusting jig 133 so as to be rotatable by a bearing 133a.
The side surface of the primary roller main body 130a has a truncated cone shape whose diameter is reduced at the front end side, and the buckling prevention roller 131 having an inverted conical side surface 131a whose diameter increases at the front end side with the connecting portion R as a boundary. Is formed.
The tip end side of the buckling prevention roller 131 is a conical portion 131b having a reduced diameter.
When the conical portion 131b on the tip side of the primary roller is inserted into the inside of the tube material 1, the mounting plate 132 is rotatable with respect to the support column 31, so that the conical portion 131b is pushed by the tube material. The roller main body 130a is automatically decentered so as to be located on the innermost side.
Therefore, with respect to the trajectory of the orbit the center 0 ₁ of column 31 of the primary roller revolves, the primary roller revolves while maintaining a state where the rotation axis center 0 ₂ is decentered innermost.
By adopting this structure, it is possible to cope with a pipe material having a diameter smaller than that of the pipe material that can be dealt with in the embodiment shown in FIG. 7 (example in which the rotation axis of the primary roller is aligned with the center of the support column).

DESCRIPTION OF SYMBOLS 1 Tubing material 1a End part 2 Collar part 5 Buckling prevention jig 5a Disc plate 5b Escape groove part 5c Shaft 10 Collapsible molding machine 11 Base plate 12 1st plate 13 2nd plate 14 Guide rod 15 Follower plate 16 Primary cylinder 17 2 Next cylinder 18 Sub guide rod 20 Main shaft motor 21 Main shaft gear 23 Rotating gear plate 30 Primary roller 31 Strut 32 Mounting portion 40 Secondary roller 41 Support base 51 Upper clamp 52 Lower clamp 130 Primary roller 131 Buckling prevention roller

Claims (3)

  The end of the tube is expanded and bent at a low angle of 60 ° or less with a conical primary roller having a rotation axis inclined toward the revolution center axis, and then the rotation axis inclined toward the revolution center axis In a tubular material forming machine that bends approximately 90 ° by a conical secondary roller having a primary roller, the primary roller has a truncated cone-shaped primary roller main body with a reduced diameter on the tip side, and a tip of the main body. A buckling prevention structure comprising an attached buckling prevention roller having an inverted conical portion.   The primary roller is rotatably attached to a support column that supports the primary roller, and the rotation shaft center of the primary roller is eccentrically attached inward to the revolution track of the revolving support column center. The buckling prevention structure according to claim 1, wherein the buckling prevention structure is provided. The end of the tube is expanded and bent at a low angle of 60 ° or less with a conical primary roller having a rotation axis inclined toward the revolution center axis, and then the rotation axis inclined toward the revolution center axis In a tube forming machine for tubular material that is bent at about 90 ° by a conical secondary roller having
Has a buckling prevention jig to be inserted inside the pipe,
A buckling prevention structure characterized in that the buckling prevention jig has a disk-like plate to be inserted inside the pipe material, and the disk-like plate has an escape groove part that squeezes the tip of the primary roller.

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