JPH06126338A - Method for bending sheet material with flange - Google Patents

Abstract

PURPOSE:To bend neatly a sheet material, such as steel sheet and synthetic resin sheet or the like having a bent flange on one side of the edge by absorbing the curvature of an excess part that is generated in the internal angle side of the flange, in the case of forming a curved part on the sheet including the flange and bending the sheet to the side of the flange. CONSTITUTION:On the sheet material 10, a bending area 14 is defined which has the same length as the arc of a prescribed curved part 15; and a trapezoid depression part 30 is formed which has the upper base 31 along the bending area 14 on the flange 13 located in the bending area 14 and which has the lower base 33 longer than the upper base 31 on the outer edge 17 of the flange 13. By adding force to the flange 13 along the bending area 14, the bottom face 34 of the depression part 30 is further deformed into a valley shape, making the side 32 of the trapezoid closer to it, and a folded part 20 is formed in the cut part 30 so as to form a valley part 22 along the bisector 21 of the depression part 30; and the final bending is performed by absorbing the bent excessive length part of the flange in this folded part 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plate material such as an iron plate or a synthetic resin plate having a bent flange on one side of an edge of a main body,
The present invention relates to a method of forming a curved portion in the main body of a plate material with the flange included and bending it toward the flange side. Specifically, it absorbs the bending of the extra length part that occurs in the side surface of the corner of the flange during bending. It is about a method of folding and folding.

[0002]

2. Description of the Related Art Generally, a plate material such as an iron plate or a synthetic resin plate having a bent flange on one side of an edge of a main body is frequently used in a simple structure having a flange as a frame. However, as shown geometrically in FIG. 4 a), when the main body 2 of the plate material 1 is bent at a right angle while the flange 3 for maintaining the strength is included, the flange 3 is bent in a random manner. When the bending process is performed, a surplus length portion that irregularly folds is formed on the entry corner side of the flange 3, so that the flanges 3 on both sides of the folding curve 4 are provided with right-angled triangular cutout portions 5 corresponding to the surplus length portion. The extra length part is absorbed especially in the outer surface side direction of the flange, and the flange 3 is restored by joining the end edge of the cut portion 5 by welding or the like. However, although this method is theoretically acceptable, in a practical method, the plate material 1 has a thickness, and the bent edge of the flange 3 from the main body portion 2 and the bending curve 4 provided on the plate material 1 are used.
Since a small curved surface is formed on the outer surface of
The processing of the cut portion 5 of the flange 3 requires not only a complicated cutting process, but also a high degree of skill in the process of restoring the smooth flange 3.

Further, the cutout portion 5 is cut out at a portion corresponding to the flange 3 at the end edge of the main body portion 2, and then the flange 3 is formed.
Even if the notch edge is joined by bending, the fact that the joining of the bending and the restoration is complicated is the same, and a step other than the bending is required. Further, when the bending process is performed along the curved portion having the width in the direction of the flange 3 on the bent portion on the outer surface side of the main body portion 2, the above method theoretically requires the obtuse angle in the bending curve 4. This must be followed by the theory that the bend and the acute triangular cutout are continuous along the curved portion for an infinitely small bent surface, which is not a practical method in terms of work efficiency.

On the other hand, as shown in FIG. 4b), a cut line 7 is provided at a right angle to the flange 3 on one side of the curved portion 6, and the flange 3 on the other side is separated by the length of the curved portion 6. The cut line 8 is formed in an arc shape in the width direction of the flange 3 from the position,
By cutting out the cut lines 7 and 8 to form the cutout portion 5 ′, it is possible to prevent the extra length portion from being generated. However, when joining the arc portion and the length portion of the bending portion 6, Joining along the small bent curved surface formed on the outer surface of the fold from the main body portion 2 of the flange 3 is more complicated and difficult than the above triangular notch. As another means, the above-described method cuts off the flange 3 of the extra length portion of the curved portion 6 along the two cut lines 7 at right angles and the fold from the main body portion 2 to form the curved portion 6. After bending the
The cut portion can be closed by the small piece of the flange member formed in a fan shape and the same bending process can be performed, but there is no great difference in the complexity of the work.

[0005]

In the actual bending of plates, the occurrence of elongation of the material itself is taken into consideration. Especially, the deformation in which a small curved surface is formed on the projecting corner side is As long as the generation of surplus material on the corner side is not hindered, it may be understood as a simple bend, and especially for a simple bend along a straight line, an extension or a small curved surface may be ignored. Therefore, regarding the various bending techniques as described above, in the bending process in the case where a flange is provided at the end edge of the main body portion, the excess length portion is cut off mainly as a treatment of the excess material portion. According to the present invention, when a plate member having a flange on one side of an end edge of a main body is bent by forming a curved portion on the main body, the plate is processed without cutting an extra length portion generated in the flange, and is smoothly folded. It is intended to provide a method of performing bending.

[0006]

In order to solve the above problems, the technical means adopted by the present invention are an iron plate, a synthetic resin plate, etc. having a bent flange on one side of the end edge of the main body. In the method of forming a curved portion in the main body portion in the direction orthogonal to the flange and bending the plate material to the flange side, a bending region equal to the arc length of the predetermined bending portion is formed in the bending portion of the plate material. And a trapezoidal recess having an upper base along the bending region and an outer edge of the flange being a lower base longer than the upper base, is formed in the flange located within the range of the bending, By applying force to the flange along the area, the bottom surface of the recess is further deformed into a valley shape, the hypotenuse of the trapezoid is brought closer, and a recess is formed to form a valley along the center bisector of the recess. A fold is formed on this part, and the extra bending length of the flange is inside this fold. Is characterized in that the bent and yield.

[0007]

[Operation] According to the present invention, a bending region forming a predetermined curved portion is defined in the main body portion of the plate material including the flange, and the trapezoidal shape is first formed along the flange located inside the bending region. A recess is formed and the formation of this trapezoidal recess provides a preliminary deformation prior to bending the curved portion of the body. This deformation first occurs in the subsequent bending process.
This is a precondition that the outer surface side of the flange does not deform due to processing. At this time, all of this deformation is formed by the deformation of the plate part of the flange, and the flange located within the range of the bending area has a step portion following the bending edge of the flange, but it is already out of the plane of the flange. Since it has been deformed, no extra length of material is generated along this step. Then, even in the hypotenuse of the trapezoid, a step is formed in the plane of the flange, but no extra length of material is generated along this step.

Therefore, when a force is applied to bend the bending region, when the bending of the main body portion extends to the flange portion, the recessed portion is out of the surface of the flange without generating an extra length portion in the surface of the flange. The internal stress easily flows to the bottom of the recess because it is deformed into a deformed shape, and the recess is deformed to form a valley along the bisector of the center of the recess. Form a fold. However, during this period, the flow of force due to bending moves to a portion with less resistance,
Since there are no parts that interfere with each other, until the final deformation is reached, it produces the same effect as if the cutout part was provided on the flange part to absorb the occurrence of the extra length part, and the actual bending process is smooth. Therefore, on the outer surface of the flange, there is no spatial problem due to deformation, and no defect occurs.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the drawings showing the embodiments. FIG. 1 shows an iron plate bent according to the present invention,
FIG. 3 is a perspective view of a plate material such as a synthetic resin plate, and FIG. 2 is a perspective view in a process before bending the plate material. In FIG. 1, the plate material 10 has a flange 13 formed by bending one end 12 of the main body portion 11 at a right angle, and the main body portion 11 of the plate material 10 is folded in a direction orthogonal to the flange 13. A bending region 14 is set, and a bent curved portion 15 is formed on the side including the flange 13. A fold portion 20 is formed on the in-plane bent portion 16 of the flange 13. In the state of FIG. 2, the bending area 1
4 is set, the main body 11 is not bent yet, and the flange 13 is formed on the plate member 10, but the main body 11 is flat. A trapezoidal recess 30 is formed on the upper surface of the flange 13 along the bending region 14.

Next, FIG. 3 shows the details of the concave portion 30,
a) is a plan view, and b) is a front view on the flange 13 side. As shown in the figure, the trapezoid of the concave portion 30 has a bent region 14
The upper base 31 is a side of the flange 13 that is parallel to the and has a substantially equal length and is separated from the bent edge of the flange 13.
7 has hypotenuses 32, 32 extending toward the outer edge 17 side, and the portion of the outer edge 17 between the ends is formed as a lower base 33, and the flange 13 is bent from the surface of the flange 13 before processing. It has a bottom surface 34 formed in parallel with 13, and its forming means is suitably formed by pressing, but is not particularly limited.

The upper base 31 of the trapezoidal recess 30 is the bending region 1.
4 has a step 35 between the bent edge of the flange 13 and the bottom surface 34, and the hypotenuse 32 has a step 36 between the top surface and the bottom surface 34 of the flange 13. The step portion 35 is formed to include a step portion 37 that is folded back with respect to the main body portion 11 within a range processed by the deformation of the flange 13 in consideration of the rigidity of the bent edge of the flange 13. Part 36
Forms an elongated triangle between the surface of the flange 13 and the bottom surface 34. Therefore, if the oblique side 32 of the concave portion 30 is set to the direction of 45 degrees that forms the triangular cutout portion on the flange 13, the step portion 36 connecting the oblique side 32 and the bottom surface 34.
Gradually changes the angle between the bent edge of the flange 13 and the outer edge 17.

To form a curved portion 15 in the bending region 14 of the plate member 10 with a flange formed as described above and bend it toward the flange side, by applying a force to the bending region 14 of the flange 13, The entire plate material 10 is curved toward the flange 13 side. Further, on the bottom surface 34, a bisector 21 may be provided by engraving or the like at the center in the lengthwise direction of the bending region 14 so that the deformation is promoted by an applied force to guide the formation of the valley 22. It is advantageous. When the bending region 14 of the main body 11 is applied with a bending force, when the bending of the main body 11 reaches the flange 13, an extra length 23 is generated in the surface of the flange 13, but the extra length 23 is generated. Already has a bottom surface 34 of the recess 30
Therefore, the internal stress easily flows into the concave portion 30, and the concave portion 30 is deformed to form the valley 22 with the bisector 21 at the center thereof as a guide line.
If it is further accelerated, a large fold 20 is formed. However, during this period, the flow of force due to bending gradually moves to a portion with less resistance and there are no portions that interfere with each other. Therefore, until the final deformation is reached, it is as if a cut portion was provided on the flange 13 portion to provide an extra length. The same effect as absorbing the occurrence of the part is produced, and the actual bending process is smooth,
On the outer surface of the flange 13, there are no spatial problems due to deformation, and no defects occur.

[0013]

The method of bending a plate member with a flange according to the present invention includes a plate member such as an iron plate or a synthetic resin plate having a bent flange on one side of the end of the main body in the direction perpendicular to the flange. In the method of forming a curved portion on the flange and bending it to the flange side, a bending area equal to the arc length of the predetermined bending portion is defined in the bending portion of the plate material, and the flange located inside the bending area is defined. A trapezoidal recess having an upper base along the bend region and an outer edge of the flange being a lower base longer than the upper base is formed, and the recess is formed by applying force to the flange along the bend region. The bottom surface is further deformed into a valley shape, the hypotenuses of the trapezoids are brought closer to each other, and a fold is formed in the recess so as to form a valley along the center bisector of the recess, and the flange of the flange is formed in this fold. Since it bends by absorbing the extra bending length, basically Only by providing a step of forming a recess in the flange portion, in particular, it can improve the bending processing method of a plate material having a curved portion. In addition, it is possible to avoid the occurrence of an irregular extra length portion in the flange due to the deformation when forming the recessed portion, and it has an absorbing action equivalent to that of forming the cut portion in the flange. Also, a fold is formed on the corner side of the curved portion, but since it is guided by the deformation of the recessed portion, it does not project to the outer surface of the flange,
Not only is there no spatial problem due to deformation, the actual bending process is smooth, and complicated work and skill are not required for flange cutouts and restoration after bending, which can impair aesthetics. Absent.

[0014]

[Brief description of drawings]

FIG. 1 is a perspective view of a plate material such as an iron plate and a synthetic resin plate bent according to the present invention.

FIG. 2 is a perspective view in a process before bending a plate material.

3A and 3B show details of a recessed portion, in which a) is a plan view and b) is a front view on a flange side.

4A and 4B are views for explaining a conventional technique of a plate material bending process, wherein a) is a perspective view of a plate material in which a part of a flange is cut off, and b) is a diagram for forming a curved portion. It is a perspective view of the plate material of the system which cuts off the flange when bent to the side.

[0015]

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plate material 2 Main body part 3 Flange 4 Folding curve 5 Excision part 6 Curved part 7, 8 Cut line 10 Plate material 11 Main body part 12 End edge 13 Flange 14 Bending area 15 Curved part 16 Bending part 17 Outer edge 20 Folding part 21 etc. Divided line 22 Valley 23 Extra length 30 Recessed portion 31 Upper base side 32 Oblique side 33 Lower bottom side 34 Bottom surface 35, 36 Stepped portion 37 Stepped portion

Claims (2)

[Claims] 1. A plate material such as an iron plate or a synthetic resin plate having a bent flange on one side of an edge of the main body portion, and a curved portion is formed in the main body portion in a direction orthogonal to the flange to bend the plate material to the flange side. In the method, a bending area equal to the arc length of the predetermined curved portion is defined in the bending portion of the plate material, and a flange located inside the bending area has an upper base along the bending area, Form a trapezoidal recess with the outer edge of the flange as a lower base that is longer than the upper base, and further deform the bottom of the recess into a valley shape by applying force to the flange along the bending region, Form a fold in the recess so as to form a valley along the center bisector of the recess, and absorb and bend the extra bending length of the flange in the fold. A method for bending a plate material with a flange, characterized by: 2. The flange concave portion has a stepped portion connected to the flange on three sides of an upper base side and oblique sides on both sides, and has a bottom surface having an outer edge of the flange as a lower base side to be a deformed flange. The bending process of the flanged plate material according to claim 1, wherein the bottom surface is provided with a guide wire so as to be deformed in a valley shape, and the folding portion is formed by a bending force. Method.