JPS6344449B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for bending a thin extruded material such as an aluminum sash frame material. This invention relates to a method that allows deformation and wrinkle-free deformation of the material.

For handrail members that are sufficiently thick and have a relatively simple cross-sectional shape, such as a "" shape, a bending method is known in which the paired members are hugged together and bent as one, thereby canceling out the torsion. It is being However, it is extremely difficult to bend a thin profile material with a complicated cross-sectional shape, such as an aluminum sash frame material, and conventional techniques have been unable to avoid twisting and deformation in the cross-section. For example, when bending a thin-walled profile 1 having a complicated cross-sectional shape as shown in FIG. Even if the web 1A was bent together with the web 1A, it was not possible to avoid deformations such as overall twisting (arrow A), collapse of the end portion 1B (arrow B), and buckling of the web 1A (arrow C). . The reason for this is that the thin walls make it impossible to resist deformation other than bending even if the end portions are assembled together. Another reason is that if the cross-sectional shape is complicated, it is not possible to restrain all the necessary parts (for example, the groove 1C, etc.) by binding, so deformation cannot be completely prevented.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems and provide a method for bending thin-walled profiles. In particular, the present invention not only makes it possible to bend thin-walled profiles in a plane parallel to the web, which has been highly desired and difficult in the past.
It is an object of the present invention to provide a method that allows bending in any plane.

To this end, the present invention involves placing a pair of mold materials parallel to each other, and in this state, casting the entire mold material with a synthetic resin that can be plastically deformed, has an appropriate hardness, and has a melting point lower than the recrystallization temperature of the mold material. After bending the synthetic resin casting body thus obtained using a bending means, the casting body is heated to a temperature lower than the recrystallization temperature of the molding material to soften the synthetic resin and forming the molding material. It is characterized by being extracted from within the synthetic resin.

Embodiments of the present invention will be described below with reference to FIGS. 2 to 10.

Figures 2-5 schematically illustrate the steps of the invention. That is, here the case is shown in which the shape material 1 shown in FIG. 1 is bent in a plane parallel to its web 1A, but the pair of shape materials 1 and 1 to be bent are first shown in FIG. The bending reference planes, that is, the webs 1A in this case, are arranged parallel to each other and are opposed to each other and held by suitable means. At this time, it is preferable that the vertical relationship (in the drawing) of the illustrated shapes 1, 1 is appropriately determined based on the cross-sectional shape of the shapes. Moreover, the distance between the two mold members is set appropriately, and it is also possible for the two mold members to be in contact with each other.

Next, as shown in FIG. 3, the entire mold members 1, 1 are cast-in with synthetic resin in this arrangement to form a cast-in body 10. The synthetic resin used here is
It is required to be plastically deformable to enable the subsequent bending process, and to be appropriately hard so as to prevent deformation other than bending of the shapes 1, 1 during the bending process. In addition, in order to avoid adversely affecting the physical properties such as the strength of the mold material made of aluminum in the casting process, it is necessary to use a synthetic resin whose melting point is lower than the recrystallization temperature of the mold material. Furthermore, it is preferable that the material has adhesive properties that allow it to adhere closely to the mold material during bending, a low shrinkage rate, and the ability to soften at a relatively low temperature. As an example, the casting temperature when the main ingredients are ethylene and wax is approximately
Synthetic resins with a softening point of about 100°C at 120-130°C can be used. It is preferable that the cast-in body 10 is a columnar member having a quadrilateral cross section as illustrated.

As shown in FIG. 4, the cast-in body 10 cast in synthetic resin is subjected to the required bending process using a normal bending process, here using a bending machine equipped with three rollers 20, 21, and 22. I do. In the illustrated embodiment, therefore, the surface 10 of the casting body 10
A, 10B must be essentially perpendicular to the plane of web 1A.

The cast-in body 10 which has been bent as a whole in this manner is then heated to, for example, above the softening point of the synthetic resin by an appropriate heating means, and the softened synthetic resin portion 11 is peeled off as shown in FIG. By doing this, the mold materials 1 and 1 are taken out. Of course, if necessary, the synthetic resin stuck to the surface of the mold material can be wiped off with a solvent such as toluene.

As is clear from the above-mentioned basic characteristics of the present invention, the mold material 1 is not bent as a single unit, but as a relatively hard cast-in body 10 that is plastically deformable and formed by being cast-in with synthetic resin. Processed. Therefore, each part of the profile 1, for example the end part 1
B and the groove portion 1C are all maintained in a predetermined shape by synthetic resin, and deformation other than twisting or bending can be prevented as much as possible. Moreover, as a result of combining the pair of shape members, it is possible to obtain a perfect matching of bending states and an effect of canceling out torsion.

Here, as shown in FIG. 6, the shrinkage δ of the synthetic resin usually occurs on the surface of the cast-in body 10 obtained in the cast-in process. If such a retraction occurs, an undesirable stress f is generated as shown in FIG. 7 during the bending process using the roller, and this causes deformation of the profile 1 other than bending. Therefore, caution is required on this point. However, on the contrary, as shown in FIG.
By forming A into a gentle convex shape, it is possible to eliminate the retraction δ, adjust the stress distribution in this part in relation to the tension generated during bending, and prevent undesirable deformation of the shape material. In addition, as shown in FIG. 9, the margin dimension α of the synthetic resin on the side 10A of the casting body 10 which is the outside of the bend is set larger than the margin dimension β of the surface 10B which is the inside of the bend, and the bending process is performed. It is also preferable to resist deformation caused by tension that sometimes acts.
However, if each mold material is cast in the opposite direction (web 1
To move A and 1A toward the upper and lower ends), conversely, the margin dimension β on the inner surface 10B side may be made larger. Incidentally, as shown in FIG. 10, when the synthetic resin is cast, spacers 30 made of stainless steel, for example, are interposed at both ends, thereby allowing the cast-in body 10 to be cast correctly.

As described above, the present invention is characterized in that the mold material to be bent is first cast in synthetic resin, and after the cast body is bent, the mold material is removed from the synthetic resin, so that the mold material is extremely thin and complicated. Even if the cross-sectional shape is large, it can be bent very easily and accurately, and twisting and other undesirable deformations can be prevented. Therefore, the range of application of the thin-walled profile material can be expanded, and many industrially advantageous effects can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing conventional problems in bending thin profile materials. 2 to 5 are perspective views showing each basic step of the present invention. FIG. 6 and FIG. 7 are cross-sectional views showing problems in forming a cast-in body.
FIGS. 8 to 10 are cross-sectional views showing modified embodiments of the cast-in body. 1... Shape material, 1A... Web, 10... Cast-in body, 20, 21, 22... Roller, 30... Spacer.

Claims (1)

[Claims] 1. A method of bending a thin-walled shape material such as an aluminum sash frame material, in which a pair of shape materials are placed parallel to each other, and in this state, the entirety of both shape materials is plastically deformed. Cast in a synthetic resin that has a suitable hardness and a melting point lower than the recrystallization temperature of the mold material,
After bending the synthetic resin cast-in body obtained in this way using a bending means, the cast-in body is heated to a temperature lower than the recrystallization temperature of the mold material to soften the synthetic resin and synthesize the mold material. A method for bending a molded material, which is characterized by taking it out from within the resin. 2. The method for bending a shape material according to claim 1, characterized in that the synthetic resin is a synthetic resin whose main components are ethylene and wax and whose softening point is approximately 100°C. 3. The method of bending a profile according to claim 1, wherein a roller-type bending machine is used as the bending means. 4. The method for bending a mold material according to claim 1, characterized in that a spacer is interposed between both ends of the mold material when the mold material is cast-in.