JPH0417732B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a method for minimizing bending of a shape material suitable for use in, for example, a train structure.

[Background of the invention]

A bending method using a conventional holding machine will be explained with reference to FIG. 1 is a material before processing, 2 is a bending machine, 3 is a bending die, and 4 is a rotation center of the bending machine 2 in the bending die 3.

In the bending method, the material 1 is attached to the bending mold 3 as shown in the figure, and the bending plate 2 is simply rotated about the rotation center 4 to the position 2' in the direction of the arrow. Therefore, the bending machine 2 bends the material 1 while rubbing it, and the material 1 is at the position 1'.

Next, a bending method using a tangential bender will be explained with reference to FIG. 5 is the mold material, 6 is the upper mold, 7
8 is a fixed plate on which the mold material 5 is pressed by the upper mold 6;
9 is a bending die, 9 is a bending die mounting plate, and 10 is a bending plate.

The profile 5 is attached to a fixed plate 7. Bending mold 8
rotates along the upper die 6 while making rolling contact. The bending die mounting plate 9 is rotatably supported by a bending disk 10 to provide rolling contact. In this case, the bending machine 10 moves around the radius center of the upper die 6, thereby moving the shape material 5 and the bending die 8.
This is a rolling contact.

The method shown in FIG. 1 above cannot be applied to flanged shapes, which are the object of the present invention, and
Although the method shown in FIG. 2 is intended for shaped materials, buckling occurs and cannot be applied particularly when the radius of curvature is small.

However, for example, in the case of a thin plate bone member with a Z-shaped cross section used in a train structure, the above conventional method cannot be applied because buckling occurs.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a bending method that prevents the occurrence of buckling at the edge of a profile when bending is performed at an extremely small curvature.

[Summary of the invention]

The present invention applies tension to a shape material set in a bending die, simultaneously pressurizes and restrains the shape material in the thickness direction of the web and in the direction of the center of rotation, and maintains the above state by applying a bead provided on the pressure die to the shape material. The material is bent along a bending die while being deformed under pressure.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 3 to 8. In the figure, 11 is a thin plate Z-shaped cross section used for example in a train structure, 12 is a bending die, 13 is a bending center that is the center of the radius of curvature R of the bending die 12, and 14 is a horizontal pressure applied to the profile 11. It is a pressurizing type that is pressurized as shown by arrows 15 and 16 in the direction and vertical pressurizing direction, and rotated as shown by arrow 17. Thus, during bending, the shape material 11 is placed in the bending die 12 with an appropriate tension 18 applied thereto. In this state, the mold material 11 is moved by the arrows 5 and 5 by the pressure mold 14.
Pressure is applied in the horizontal and vertical directions indicated by 6, and the horizontal direction of pressure is always in the direction of the bending center 13. Note that the tension 18 is adjusted as appropriate depending on the shape and material of the mold material 11.

The structure of the pressure mold 14 will be explained with reference to FIGS. 4, 5, and 6. The pressing mold 14 has a semicircular vertical pressing surface bead 19 at a portion that presses the web surface of the mold material 1 (the pressing direction is the vertical pressing direction indicated by arrow 6), and this bead 19 is bent. It has a tapered shape from the outside to the inside in the radial direction, and the bead thickness is thicker on the outside and becomes thinner toward the inside. and,
A semicircular horizontal pressure surface bead 20 is also provided at the portion where the flange surface (flange on the outside in the bending radius direction) of the profile 11 is pressed, and unlike the bead 19, this is not tapered.

When bending the shape material 11, the pressure mold 14 is held pressed against the shape material 11 placed under tension in the bending mold 12 as shown by arrows 15 and 16, and rotated around the bending center 13 as shown in the arrow 17. Perform rotational movement to perform radius bending. At this time, the pressurizing die 14 is in a state of rolling the mold material 1 by the beads 19 and 20 provided on the mold material 11 side. This will be explained with reference to FIGS. 7 and 8.

That is, the web and flange face plate thickness (outside of the bending radius direction) of the profile 11 are locally pressed and rolled by the beads 19 and 20 of the pressure die 14, and the thickness of the profile 1 is reduced. This causes the pressurized part to stretch.

As described above, the shape material 1 is subjected to tension and is bent while being stretched at its outer edge by the pressure mold 14, so that bending with a minimum radius of curvature can be performed while preventing the occurrence of buckling.

〔Effect of the invention〕

According to the present invention, it is possible to perform extremely small bending without causing buckling deformation in the shape material, and there is an effect that the bending area can be expanded compared to the conventional method.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of the bending method using a holding machine, Fig. 2 is a plan view of the bending method using a tangential bender, Fig. 3 is a three-dimensional view showing an embodiment of the bending method according to the present invention, and Fig. 4 is a front view of the pressurized type, Fig. 5 is a side view of the pressurized type, and Fig. 6 is a 4th view of the pressurized type.
7 is a sectional view taken along the line AA in FIG. 3, and FIG. 8 is a sectional view taken along the line C-C in FIG. 7. 11... Shape material, 12... Bending die, 13... Bending center, 14... Pressing die, 15... Arrow (horizontal pressing direction), 16... Arrow (vertical pressing direction), 17...
Arrow (rotation direction of pressure mold), 19... bead for vertical pressure surface, 20... bead for horizontal pressure surface.

Claims (1)

[Claims] 1 Apply tension to the shape material set in the bending die, simultaneously pressurize and restrain the shape material in the direction of the thickness of the web and in the direction of the center of rotation, maintain the above state, and pressurize the shape material with the bead provided in the pressure die. A method for extremely small bending of a shape material, characterized by bending it along a bending die while deforming it.