JPH10192992A - Method for bending long size metal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively prevent the generation of the deformation of cross-section shape or wrinkles following to bending of a metal and to easily and inexpensively produce a bending article having the high value of goods by fitting a restricting dummy, bending the long size metal in this fitting state and then removing the restricting dummy. SOLUTION: A mandrel 3 is inserted in a body part 10, respective fin like projection parts 11a, 11b are fitted with restricting dummies 2A, 2A providing proper fitting grooves 21, after bending them in this state, the restricting dummies 2A, 2A are removed. Therefore, each restricting dummy 2A is bent as one body with the metal 1A, however, the fin like projection parts 11a, 11b clamped with the grooves 21 are restricted and not allowed to change the shape except the bending direction, on the result, the circular arc like bending article without generating incline or wrinkles on the fin like projection parts 11a, 11b is easily obtained. Further, the restricting dummies 2A, 2A are easily taken out from the metal 1A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for bending a long metal material such as an extrusion material or a roll forming material into a curved shape such as an arc shape. It is used for processing into arch-shaped sashes at the opening of buildings, arc-shaped frames at the ceiling of the solarium, and the like.

[0002]

2. Description of the Related Art Conventionally, in bending a long metal material such as an extrusion material or a roll forming material, the long metal material has a hollow portion as a means for preventing deformation of a cross-sectional shape due to the bending. In such a case, a method of inserting a mandrel (core rod) into the hollow portion and constraining the other outer peripheral portion by a bending die is generally adopted.

However, the conventional deformation preventing means has insufficient binding force. In particular, when the long metal material has a fin-shaped projection continuous in the longitudinal direction on the outer periphery of the main body, the projection is not suitable. Even if the long metal material has a rectangular cylindrical shape, even if the long metal material has a rectangular cylindrical shape, if the length of one side of the rectangle is large, insert a mandrel into the hollow part There is a problem that wrinkling on the side surface along the inside (concave side) of the bending is inevitable even when the processing is performed.

As another means for preventing deformation, there is a method in which the outside of a long metal material is wrapped with a low melting point alloy and bent. However, in this method, it is necessary to melt and remove the low melting point alloy by heating after the processing. Therefore, there is a problem that it is very troublesome and the processing cost is high.

[0005]

SUMMARY OF THE INVENTION In view of the above-mentioned circumstances, the present invention provides a method of bending a long metal material by using a simple means to reduce the deformation of the cross-sectional shape of the metal material and the occurrence of wrinkles. It is intended to provide a method that can be effectively prevented without using the method.

In order to achieve the above object, in the bending of a long metal material according to the first aspect of the present invention, at least a part of the outer periphery of the long metal material has a fitting portion adapted to the outer shape thereof. And fitting the restraining dummy made of a material that can bend and capable of expressing a restraining force, bending the long metal material in this fitted state, and then removing the restraining dummy. The configuration is adopted. That is, according to this configuration, since the long metal material is bent while the outer periphery is restrained by the restraining dummy, deformation of the cross-sectional shape and generation of wrinkles are prevented. Further, since the restraining dummy is merely fitted to the long metal material, mounting before processing and removal from the metal material after processing can be performed very easily.

According to a second aspect of the present invention, in the bending of the long metal material according to the first aspect, the long metal material has a fin-like projection continuous in the longitudinal direction on the outer periphery of the main body. The protruding portion is fitted with a restraining dummy, and the long metal material is bent in a plane including the protruding direction of the fin-shaped protruding portion. In the case of bending such a long metal material, the fin-shaped projections are particularly subjected to a large expansion and contraction action. However, since the projections are restrained by the restraining dummy, deformation and wrinkling are prevented. Will be.

According to a third aspect of the present invention, in the bending of the long metal material according to the first aspect, the long metal material has a rectangular cylindrical shape, and the restraining dummy has a U-shaped cross section fitted to the metal material. It has a configuration to make. In this case, even if the long metal material is thin and has a large rectangular dimension, and therefore easily deforms due to bending, the deformation of the cross-sectional shape and the generation of wrinkles are prevented by the restraining force of the restraining dummy. Will be.

According to a fourth aspect of the present invention, in the bending of the long metal material according to any one of the first to third aspects, the restraining dummy is an extruded material of aluminum or an alloy thereof, a roll forming material, a hard synthetic resin or a hard synthetic resin. It consists of a kind selected from rubber moldings. Therefore, a restraining dummy having a fitting portion shape suitable for a long metal material to be bent can be mass-produced at low cost.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION A long metal material to which the bending method of the present invention is applied is generally metal in terms of material and is not particularly limited in form. Extrusion mold materials made of alloys, as well as linear roll forming materials in which uneven portions that are continuous in the longitudinal direction are formed by roll printing pressure on various metal rods and strips, and among these, particularly in form and dimensions It is preferable to use a material having a portion where deformation of the cross-sectional shape or wrinkling is likely to occur due to bending.

For example, in the case of a long metal material having a fin-shaped protrusion continuous in the longitudinal direction on the outer periphery of a main body such as a cylinder or a channel, an arc-shaped or the like is formed in a plane including the protruding direction of the fin-shaped protrusion. When bending into a curved shape, deformation of the main body can be prevented by inserting a mandrel, but the fin-like projections located inside (concave side) of the bend with respect to the main body are reduced by shortening the longitudinal dimension. Shrinkage wrinkles are generated, and the fin-like projections located on the outer side (convex side) are liable to be deformed such that the fin-like projections are pulled down and inclined by the extension of the same size. In addition, even a simple rectangular cylindrical long metal material having no fin-shaped protrusions, a thin metal material having a large rectangular side length, for example, an aluminum or its alloy extruded material generally has a thickness of 2 mm.
In the case of one having a side of 40 mm or more, even if a mandrel is inserted into the inside and bending is performed, a shape change, in particular, generation of wrinkles on the side surface along the inside of the bending is inevitable.

However, according to the bending method of the present invention,
The bending process is performed in a state where the restraining dummy is fitted to at least a part of the outer periphery of the long metal material that is liable to cause the deformation and wrinkles of the cross-sectional shape due to the bending as described above, so that the deformation and the wrinkles of the cross-sectional shape are reduced. Prevent occurrence. That is, the restraining dummy is bent integrally with the metal material, but the outer peripheral portion of the metal material restrained by the restraining dummy is prevented from changing its shape other than in the bending direction, so that the deformation and wrinkling do not occur. By removing the restraining dummy after bending, a bent product having high commercial value can be obtained. Further, since the restraining dummy is merely fitted to the long metal material, it can be very easily mounted before processing and removed from the metal material after processing.

The restraining dummy restrains only a portion of the outer periphery of the long metal material which is liable to undergo a shape change or wrinkles. For example, in the case of the long metal material having the fin-like protrusion, the fin-like protrusion is particularly used. In the case of a long rectangular metal material having a large thickness on one side, it is only necessary to fit so as to restrict the side part, which is the inside of the bend. The entire outer periphery of the metal material may be wrapped. In the case where the long metal material has a hollow portion, a mandrel may be inserted into the hollow portion in the same manner as in the related art, and a bending process may be performed by fitting a restraining dummy to the outer periphery. As the bending means, various methods such as a roll forming method which have conventionally been used when a long metal material is formed into a curved shape such as an arc shape can be adopted.

The restraining dummy has a fitting portion adapted to the outer shape of the long metal material to be bent, and can be bent integrally with the metal material along with the bending of the metal material so that the restraining force can be reduced. Any material can be used as long as it is bendable and capable of exhibiting a binding force, and can be a metal material such as an extruded material of aluminum or an alloy thereof, or a concave portion serving as a fitting portion such as a groove. This is preferable because a linear roll forming material formed by a roll printing pressure, a molded product made of a hard synthetic resin or a hard rubber can be mass-produced at low cost. Further, in particular, a restraining dummy made of aluminum or an alloy thereof or a thermoplastic synthetic resin has an advantage that a material that has been subjected to bending and deformed by bending can be melted and reused. 1 shows a long metal material (1A) used in one embodiment. This long metal material (1A)
Are fin-shaped protrusions (11a) perpendicular to the side surfaces and continuous in the longitudinal direction at the center positions of the left and right sides of the main body (10) in the form of a rectangular tube. ) (11b). Then
As shown by the imaginary line in FIG.
One fin-like projection (11a) is inside the bend (concave side),
When the other fin-like projection (11b) is bent into an arc shape having the same outer side (convex side), as shown in FIG. 2, the mandrel (3) is inserted into the main body (10) as in the conventional case. At the same time, each of the fin-like projections (11a) and (11b) has a groove (21) having a groove (21) that fits into each of them.
A) After fitting (2A) and performing bending in this state, the restraining dummy (2A) (2A) is removed. As a result, each restraining dummy 2A is bent integrally with the metal material 1A, but the fin-like projections (11a) and (11b) sandwiched between the grooves (21) are restrained, and a change in shape other than the bending direction is allowed. However, the fin-like projections (11a) (1
An arc-shaped bent product without the inclination and wrinkle of 1b) can be easily obtained. Bending restraint dummy (2A)
(2A) can be easily removed from the metal material (1A).

FIG. 3 shows a long metal material (1B) used in a second embodiment of the bending method according to the present invention. The long metal material (1B) is made of an extruded material of aluminum or an alloy thereof, and has a simple rectangular cylindrical shape without fin-like projections as the metal material (1A) of the first embodiment. It is as thin as 2 mm or less, and the dimension of one side is as large as 40 mm or more. When this long metal material (1B) is bent into an arc shape, a mandrel (3) is inserted inside and
A pair of U-shaped constraining dummies (2) having concave portions (22) corresponding to the half-divided size of the metal material (1B)
B) (2B) is fitted so as to surround the outside of the metal material (1B), bending is performed in this state, and then both restraining dummies (2B) and (2B) are removed. This allows
Although both restraining dummy members (2B) and (2B) are bent integrally with the metal material (1B), the metal material (1B) does not change its cross-sectional shape or wrinkle because the entire outer periphery is restrained. Thus, a bent product having a good appearance can be easily obtained. Further, the restraining dummies 2B, 2B after bending can be easily removed from the metal material (1B).

In the first embodiment, a long metal material having one fin-like projection (11a) and one fin-like projection (11b) on both left and right sides of a rectangular cylindrical main body (10) is exemplified. According to the present invention, various long metal materials having different formation positions, numbers, widths, thicknesses, and the like of the fin-shaped protrusions are provided with a groove having an appropriate fitting corresponding to the fin-shaped protrusions. By using the dummy, the bending process can be performed without causing deformation or wrinkles in the fin-like projections. In addition, the bending method of the present invention
In a long metal material having these fin-shaped protrusions, the main body forms a hollow portion such as a cylinder, an elliptic cylinder, or a polygon other than a quadrangle, and further, the main body has a non-cylindrical frame such as a channel. The present invention is also applicable to those having a continuous shape, such as a screw groove, on the inner surface or the outer surface of the long metal material regardless of the presence or absence of the fin-shaped protrusion.

[0017]

According to the first aspect of the present invention, in the bending of a long metal material, the deformation of the cross-sectional shape and the occurrence of wrinkles due to the bending of the metal material can be effectively prevented by extremely simple and inexpensive means. And a method for easily and inexpensively producing a bent product having high commercial value.

According to the second aspect of the present invention, in the bending of the long metal material, particularly, the long metal material having a fin-shaped projection continuous in the longitudinal direction on the outer periphery of the main body is provided. When the metal material is bent in a plane including the protruding direction of the fin-like projections, it is possible to reliably prevent the fin-like projections from being deformed or wrinkled.

According to the third aspect of the present invention, in the above-mentioned bending process for a rectangular cylindrical long metal material, the metal material is particularly thin and large in rectangular size which is easily deformed by bending. However, the deformation and wrinkles can be reliably prevented.

According to the fourth aspect of the present invention, in the bending of the long metal material, a restraining dummy used to prevent a change in shape and wrinkles of the metal material can be obtained at a low cost. There is an advantage that the processing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view of a long metal material applied to a first embodiment of a bending method according to the present invention.

FIG. 2 is a perspective view showing a fitting state of a restraining dummy to a long metal material in the first embodiment.

FIG. 3 is a cross-sectional view showing a fitting state between a long metal material and a restraining dummy applied to a second embodiment of the bending method of the present invention.

[Explanation of symbols]

 1A, 1B: Long metal material 10: Main body 11a, 11b: Fin-like projection 2A, 2B: Restriction dummy 21: Groove (fitting portion) 22: Recess (Mating part) 3 ・ ・ ・ Mandrel

Claims (4)

[Claims] Claims: 1. At least a part of the outer periphery of a long metal material,
Fitting a restraining dummy made of a material capable of expressing a restraining force that can be bent with a fitting portion adapted to the outer shape,
A method for bending a long metal material, comprising bending the long metal material in the fitted state and removing the restraining dummy. 2. The elongated metal material has a fin-shaped projection on the outer periphery of the main body in the longitudinal direction, and a restraining dummy is fitted to the fin-shaped projection, and the elongated metal material is attached to the fin-shaped projection. 2. The method for bending a long metal material according to claim 1, wherein the bending is performed in a plane including the projecting direction of the portion. 3. The method of bending a long metal material according to claim 1, wherein the long metal material is a rectangular cylinder, and the restraining dummy has a U-shaped cross section fitted to the metal material. 4. The restraining dummy is made of one selected from an extruded material of aluminum or an alloy thereof, a roll forming material, a molded product of a hard synthetic resin or a hard rubber.
4. The method for bending a long metal material according to any one of items 1 to 3.