JPH11138211A - Offset bending device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To raise workability by reducing the dimension of the height of offset bending and enabling working by one process. SOLUTION: This device is a working device for executing offset bending work for bending and forming the edge on one side of a metallic sheet 1 into a crank shape and a punch 2 having a crank part 2a for fixing the edge side of the metallic sheet 1 into the crank shape, slide cam 3 which is sliding moved in the direction of the crank part 2a of the punch 2 and also has a taper-shaped cam part, pressing cam 5 for pressing and energizing by bringing an working part 5a into contact with the taper-shaped cam part 3a of the slide cam 3 and knockout 6 on which the metallic sheet 1 is placed and also which is lowered by pressing with the punch 2 are at least provided. By energizing by the pressing cam 5 by pressing it against the taper-shaped cam part 3a of the slide cam 3, the slide cam 3 is slid on the side of the punch 2 and, on the other hand, in the process where the metallic sheet 1 is lowered together with the knockout 6 by pressing with the punch 2, pressing force is acted in the direction of the crank part 2a of the punch 2 with the slide cam 3 and the edge side of the metallic sheet 1 is bent and formed into the crank shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an offset bending apparatus for offset bending an edge of a metal plate.

[0002]

2. Description of the Related Art When offset bending is performed on an edge of a metal plate, a processing method shown in FIGS. 8 to 10 is known. FIG. 8A shows an apparatus for bending the edge side of a metal plate by press working. That is, the guide portion 21 and the knockout 22 are provided on the fixed side of the press machine,
A punch 23 is provided on the movable side of the press. Then, after the flat metal plate 20 is placed on the guide portion 21 and the knockout 22 as shown by a dashed line, the punch 2
As the knockout 22 descends, the metal plate 20 is subjected to the first bending as shown in FIG. Thereafter, as shown in FIG. 9, the bending position 20a apart from the edge of the metal plate 20 is bent in the direction indicated by the arrow by a known method, and is erected to perform offset bending on the edge of the metal plate 20. Is done.

As another processing method, an arrow-shaped bending processing shown in FIG. 10 is known. That is, first, as the first processing, the edge side of the metal plate 20 is bent in a substantially arrow shape so that the bending angle becomes 90 degrees as shown in the figure, and then, as the second processing, the end of the metal plate 20 is formed. By erecting the bent portion away from the edge, the edge of the metal plate 20 is subjected to offset bending.

[0004]

However, these conventional offset bending processes have the following technical problems.

First, in the working method shown in FIG. 8, as a first bending work, the punch 23 is lowered and the flat metal plate 20 is forcibly punched while sliding on the corner of the guide portion 21. 8A, there is a problem that the side surface of the metal plate 20 indicated by a circle in FIG. 8A is scratched and loses commercial value. Further, when the metal plate 20 is pushed between the punch 23 and the guide portion 21, the metal plate 20 is stretched, and there is a problem that the plate thickness t of the bent portion is reduced. Further, the height dimension h of the offset bending shown in FIG. 9 cannot be made three times or less the thickness of the metal plate 20 in the normal bending, and it has been impossible to perform the offset bending with a small dimension.

On the other hand, in the case of the arrow-shaped bending shown in FIG. 10, although the edge of the metal plate 20 can be bent with a relatively small bending dimension, the metal plate 20 is bent from the edge in the second step. There has been a problem that the height dimension of the offset bending in which the separated bent portion 20b is erected cannot be less than three times the thickness of the metal plate 20. As described above, it is virtually impossible to perform offset bending with small dimensions by any of the conventional processing methods, and a serious problem that a metal plate subjected to offset bending cannot be used in various devices that are becoming smaller in size. There is. Further, the processing methods shown in FIGS. 8 to 10 both require the first and second steps for offset bending, and there is also a problem that the cost is necessarily increased.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and it is possible to reduce the height of offset bending and to perform processing by one process. It is an object of the present invention to provide an offset bending apparatus capable of improving the bending property.

[0008]

Means for Solving the Problems In order to achieve the above object, the invention according to claim 1 is a processing apparatus for performing an offset bending process for bending at least one edge of a metal plate into a crank shape. A metal plate, a punch having a crank portion for determining an edge side of the metal plate in a crank shape, a slide cam having a tapered cam portion while sliding in the direction of the crank portion of the punch,
The slide cam includes at least a pressing cam for pressing and pressing the action portion against the tapered cam portion of the slide cam, and a knockout for placing the metal plate and descending by pressing the punch. While the pressing cam is urged against the tapered cam portion to slide the slide cam toward the punch, the slide cam is knocked out and the metal plate is lowered by pressing the punch. It is characterized in that an end side of the metal plate is bent into a crank shape by applying a pressing force in a part direction.

According to the present invention, in the process of lowering the metal plate by pressing the punch, the slide cam applies a pressing force in the direction of the crank portion of the punch to bend the edge of the metal plate into a crank shape. Offset bending can be performed in a single step, so that manufacturing costs can be reduced and workability can be improved. In addition, since the bending is performed by the pressing force of the slide cam, the workpiece can be processed with high accuracy even when the height of the offset bending is small. Further, since the metal plate is bent by the slide cam while the metal plate is lowered, the commercial value can be increased without causing a sliding scratch on the metal plate.

Further, the invention according to claim 2 is characterized in that a tapered surface is formed on the action portion of the pressing cam, and this tapered surface is slidably abutted on the tapered cam portion of the slide cam. . Therefore, by changing the taper angle of the action portion of the pressing cam and the taper angle of the tapered cam surface of the slide cam, the movement amount and the pressing force of the slide cam can be appropriately set.

Further, the invention according to claim 3 is characterized in that the tapered cam portion of the slide cam is set at an angle of one half of the bending angle of the metal plate with respect to the slide direction. Therefore, since the slide cam presses from the center when the metal plate is bent, even if the thickness of the metal plate changes, the variation in the bending angle is reduced, and the bending accuracy is improved.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below in detail based on an embodiment shown in the drawings.

1 to 3 show an offset bending apparatus according to the present invention. FIG. 1 shows an example of a final state processed by the offset bending apparatus. FIG. 2 shows an initial state of the offset bending processing. FIG. 3 shows an intermediate state.

First, the configuration of the offset bending apparatus will be described. Reference numeral 2 denotes a punch, and the punch 2 is attached to a vertically movable part of a press (not shown).
On one side of a lower end of the punch 2, a crank portion 2a for forming an edge side of a metal plate 1 described later into a crank shape is formed. Reference numeral 3 denotes a slide cam, which is housed in a guide groove 4a of the fixed frame 4 and is slidably movable left and right in the direction of the crank 2a of the punch 2, as shown in FIG.

Further, a tapered cam portion 3a having an angle of 45 degrees with respect to a horizontal plane is formed on the right shoulder of the slide cam 3. 5 is a pressing cam, which is a slide cam 3
The action portion 5a is brought into contact with the tapered cam portion 3a to press and urge the working portion 5a downward.
Attached to a movable part that moves up and down of a press machine (not shown). Reference numeral 6 denotes a knockout, which is configured so that the metal plate 1 is placed and the punch 2 presses the punch 2 to slide down the inner surface of the hole 4b of the fixed frame 4 and move down. Reference numeral 7 denotes an urging spring formed of a coil spring or the like, which normally urges the knockout 6 to the position shown in FIG.

Next, a process of offset bending the metal plate 1 into a crank shape by using the offset bending apparatus will be described. First, in the initial state,
The punch 2 of the offset bending apparatus is located at a position higher than the upper surface of the fixed frame 4. In this initial state, the metal plate 1 to be subjected to offset bending is inserted into the fixed frame 4, and the metal plate 1 is positioned and placed on the knockout 6 and the upper surface of the slide cam 3.

After that, the punch 2 and the pressing cam 5
As shown in (2), the fixing frame 4 descends while sliding on the inner surface of the hole 4b. When the punch 2 presses the metal plate 1, the knockout 6 moves down together with the metal plate 1 against the urging force of the urging spring 7 due to the pressing of the punch 2. At this time, the action portion 5a of the pressing cam 5 descends in the direction indicated by the arrow 3, and presses and biases the tapered cam portion 3a of the slide cam 3. Due to the urging force of the pressing cam 5, the slide cam 3 slides on the action portion 5a, and thereby slides to the left in the drawing at right angles to the direction of the urging force of the pressing cam 5.

When the metal plate 1 is lowered in this manner, the edge of the metal plate 1 comes into contact with the shoulder of the slide cam 3, and
As shown in (2), the punch 2 bends from the lower end of the crank portion 2a. In this state, the pressing force p1 downward in the figure due to the lowering of the punch 2 and the pressing force p2 to the left in the drawing of the slide cam 3 due to the pressing of the pressing cam 5 act on the edge side of the metal plate 1. In this state, the downward pressing force p is substantially applied to the slide cam 3 against the edge of the metal plate 1.
1 and the pressing force P2 to the left, a vector-combined biasing force P
Is equivalent to generating

Since the biasing force P of the slide cam 3 is directed toward the inner angle of the crank portion 2a of the punch 2, the position of the crank portion 2a between the bent point on the edge side of the bent metal plate 1 and the edge is changed. The metal plate 1 is pressed toward the inner corner, and finally the metal plate 1 is bent in a crank shape as shown in FIG.

Thereafter, when the punch 2 is raised and the pressing cam 5 is raised, the slide cam 3 is returned to the right side in the figure by the tension spring 8 and returns to the initial state. When the metal plate 1 is taken out of the offset bending apparatus in this state, a final product shown in FIG. 4 is completed.

When the offset bending process is performed on the metal plate 1 by the offset bending device described above, the slide cam 3 is substantially vector-combined with the biasing force P with respect to the right angle of the crank portion 2a of the punch 2. As a result, the edge of the metal plate 1 is pressed at an angle of about 45 degrees. Therefore, two edges are formed on the edge side of the metal plate 1 by one process.
Since the bending process can be performed at each location and the bending process is performed by the biasing force P in the oblique direction obtained by the vector synthesis, the conventional 2
The accuracy can be greatly improved as compared with the bending process in the process. Further, the stress on the metal plate 1 can be minimized by the urging force P.

FIG. 6 shows a second embodiment of the offset bending apparatus according to the present invention. In the second embodiment, both ends of the metal plate 1 can be simultaneously subjected to offset bending. That is, the punch 12 attached to a vertically movable part of a press machine (not shown) has crank portions 12a and 12b formed on both sides of a lower end for forming both ends of the metal plate 1 into a crank shape. Also, the crank portion 12 of the punch 12
a, a pair of slide cams 13, 1
4 is accommodated in the guide groove 4 a of the fixed frame 4. Each of the pair of slide cams 13 and 14 has a guide groove 4a.
The slide cams 13 and 14 are provided with tension springs (not shown) for always returning to the left and right origin positions, respectively.

Further, tapered cam portions 13a and 14a having an angle of 45 degrees with respect to a horizontal plane are formed on the shoulders of the slide cams 13 and 14, respectively.
The action portions 15a and 16a of the fifth and the 16 are brought into contact with each other, and are urged downward. The base ends of the pressing cams 15 and 16 are attached to a vertically movable movable portion of a press (not shown) together with the punch 12. Further, since the knockout 6 is used to press and bias the knockout 6 and is similar to the above-described embodiment, the description thereof is omitted.

Next, a description will be given of a step of offset bending the metal plate 10 into a crank shape at both end sides using the offset bending apparatus. However, the description of the steps similar to those in the above-described embodiment will be repeated. Only the steps unique to the second embodiment will be described.

Knockout 6 and slide cams 13, 1
The punch 12 and the pressing cams 15 and 16 are lowered toward the metal plate 1 placed and placed on the upper surface of 4 as shown by arrows in FIG. The metal plate 1 descends together with the knockout 6 against the urging force of the urging spring 7. At the same time, the action parts 15a and 16a of the pressing cams 15 and 16 are lowered in the direction of the arrow,
The third and fourth tapered cam portions 13a and 14a come into contact with each other and are pressed and urged. The slide cams 13 and 14 slide toward the center by the urging force of the press cams 15 and 16.

As the metal plate 1 descends, both ends of the metal plate 1 are bent by contacting the shoulders of the slide cams 13 and 14. Thereafter, similarly to the above-described embodiment, the pressing force due to the lowering of the punch 12 and the sliding pressing force of the slide cams 13 and 14 due to the pressing of the pressing cam 5 act on the edge side of the metal plate 1 respectively. The urging force resulting from the vector synthesis is directed toward the inner angles of the crank portions 12a and 12b of the punch 12. As a result, the slide cams 13 and 14
Are pressed toward the inner corners of the crank portions 12a and 12b, respectively, and finally, the offset bending process in which both ends of the metal plate 1 are bent in a crank shape is completed.

According to the second embodiment, the metal plate 1
Is characterized in that offset bending can be performed in one step on both end sides. In some cases, offset bending may be performed once on both edge sides of the metal plate 1 and then, for example, the center portion may be cut off to reduce the manufacturing cost. The offset bending process performed on the both edge sides of the metal plate 1 is not necessarily parallel, but may have an arbitrary angle.

FIGS. 7A and 7B show a modified example of the offset bending apparatus according to the present invention. FIG. 7 (A)
Is a modified example of the second embodiment, in which the bending angle of the offset bending process performed on both end sides of the metal plate 1 is set to an angle other than 90 degrees. That is, the angles of the crank portions 12a and 12b formed on both sides of the lower end of the punch 12, the inner angle θ1 of one of the crank portions 12a is set to 60 degrees,
The inner angle θ2 of the other crank portion 12b is set to 120 degrees. Also, a crank portion 12a of the punch 12,
The outer angles of the pair of slide cams 13 and 14 corresponding to 12b are also set to the same angles as 60 degrees and 120 degrees, respectively. Further, the action portion 15a of the pressing cam 15, and
The angle of the tapered cam portion 13a of the slide cam 13 is set to 30 degrees, which is one half of the inner angle θ1 of the crank portion 12a. Also, the action portion 1 of the other pressing cam 16
6a and a tapered cam portion 14a of the slide cam 14
Is set to a half of 60 degrees with respect to the inner angle θ2 of the crank portion 12b.

When the punch 12 and the pressing cams 15 and 16 are lowered and the metal plate 1 is pressed by the punch 12 in the same manner as in each of the above-described embodiments, the pressing force by the lowering of the punch 12 and the pressing force by the pressing cam 5 Slide cam 13, 1
The urging force resulting from the vector composition of the slide pressing force of No. 4 acts so as to be directed toward the center of the inner corners of the crank portions 12 a and 12 b of the punch 12. For this reason, even if the inner angle θ1 of the crank portion 12a of the punch 12 is set to an acute angle, the slide cams 13 and 14 press the edge sides of the metal plate 1 toward the centers of the inner angles of the crank portions 12a and 12b, respectively. Therefore, the metal plate 1 can be easily subjected to the offset bending process bent in a crank shape. As described above, since the slide cams 13 and 14 are pressed from the center of the inner angles of the crank portions 12a and 12b, the slide cams 13 and 14 are always pressed from the center of the bending angle even if the thickness of the metal plate 1 is different. The feature is that the variation in the angle due to the change in thickness is eliminated, and the bending accuracy is further improved. .

FIG. 7B shows a modification of the first and second embodiments, in which multi-stage offset bending is performed. That is, the crank part 2a formed at the lower end of the punch 2 is formed in two steps as shown in the figure,
The slide cam 3 corresponding to the crank portion 2a of the punch 2 is also formed in two stages. As described above, when the metal plate 1 is processed by the offset bending processing having the multi-stage configuration,
Since the slide cam 3 presses the edge side of the metal plate 1 toward the inner angle of each multi-stage crank portion 2a, the metal plate 1
Can be easily subjected to multi-stage offset bending.

As described above, the present invention has been specifically described based on the embodiments. However, the present invention is not limited to the above embodiments, and may be variously modified without departing from the gist thereof. Needless to say. For example, in each of the above-described embodiments, a tapered cam portion having an angle of 45 degrees with respect to a horizontal plane is formed on the right shoulder of the slide cam, and the action portion of the pressing cam is brought into contact with the tapered cam portion. The tapered cam portion can be set at any angle other than 45 degrees. Since the pressing force of the slide cam against the crank portion of the punch can be changed by this angle, it can be appropriately set according to the thickness and hardness of the metal plate or the capability of the press.

In each of the above embodiments, a tapered cam portion is formed on the right shoulder of the slide cam, and the action portion of the pressing cam is brought into contact with the tapered cam portion in a surface-joined state to urge the slide cam. However, the action portion of the pressing cam may be formed in, for example, a semi-cylindrical shape, and may be slid in a line-joined state to urge the pressing portion. Further, even if the tapered cam portion formed on the slide cam is not flat, it may be curved concavely or convexly so that the pressing force of the slide cam against the crank portion of the punch is changed in accordance with the process of machining. Good.

[0033]

According to the present invention described above, in the process of pressing the metal plate by the punch, the slide cam exerts a pressing force in the direction of the crank portion of the punch, so that the offset is applied to the edge of the metal plate in one step. Bending can be performed, and workability can be improved. In addition, since the bending is performed by the pressing force of the slide cam, the workpiece can be processed with high accuracy even when the height of the offset bending is small. Furthermore, since the metal plate is bent by the slide cam while the metal plate is lowered, the commercial value can be increased without causing sliding scratches on the metal plate.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an offset bending apparatus according to the present invention.

FIG. 2 is a cross-sectional view showing an initial state of offset bending according to the present invention.

FIG. 3 is a cross-sectional view showing an intermediate state of offset bending according to the present invention.

FIG. 4 is a perspective view showing a final product subjected to offset bending by the offset bending apparatus according to the present invention.

FIG. 5 is a plan view showing a fixing frame of the offset bending apparatus according to the present invention.

FIG. 6 shows a second embodiment of the offset bending apparatus according to the present invention.
FIG. 4 is a cross-sectional view showing an embodiment of the present invention.

FIGS. 7A and 7B are cross-sectional views illustrating a modified example of the offset bending apparatus according to the present invention.

FIG. 8 is a sectional view of a main part showing a conventional offset bending apparatus;

FIG. 9 is an explanatory view showing a conventional offset bending method;

FIG. 10 is an explanatory view showing another method of the conventional offset bending method,

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Metal plate 2 Punch 3 Slide cam 3a Tapered cam part 4 Fixed frame 5 Pressing cam 6 Knockout 7 Urging spring P Pressing force

Claims (3)

[Claims] 1. A processing apparatus for performing an offset bending process for bending at least one edge of a metal plate into a crank shape, comprising: a metal plate; and a crank portion for determining an edge side of the metal plate into a crank shape. , A slide cam that slides in the direction of the crank portion of the punch and has a tapered cam portion, and a pressing force for pressing and urging the tapered cam portion of the slide cam by contacting the action portion. A cam, and at least a knockout for placing the metal plate and descending by pressing the punch, pressing the pressing cam against the tapered cam portion of the slide cam to push the slide cam toward the punch. On the other hand, in the process of knocking out and lowering the metal plate by the pressing of the punch, the slide cam causes the punch of the punch to slide. An offset bending apparatus characterized in that an end side of the metal plate is bent into a crank shape by applying a pressing force in a direction of a rank. 2. A tapered surface is formed on the action portion of the fixed cam,
2. The offset bending apparatus according to claim 1, wherein said tapered surface is slidably contacted with a tapered cam portion of a slide cam. 3. The offset bending apparatus according to claim 1, wherein the tapered cam portion of the slide cam is set at an angle of one half of a bending angle of the metal plate with respect to the sliding direction.