JPH10202321A - Pressing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the surface of a work from being damaged by eliminating the displacement of the rotation angle of each rotary cam and the difference of deflecting amount of each back-up punch which are generated caused on the difference of load applying to each rotary cam in plural numbers of rotary cam mechanism arranged continuously, and preventing the generation of step difference between the adjoining rotary cams and the back-up punches. SOLUTION: This pressing device is used by continuously arranging plural numbers of rotary cam mechanisms 10 of the composition where a circular column shaped rotary cam 18 is assembled against a lower die holder 14 freely rotating around the axial line, and a part of the outside circumference face of this rotary cam is born with a back-up punch 16 fixed on the lower die holder 14, and the back-up punches 16 of mutually adjoining in each rotary cam mechanism 16 are connected mutually with connecting members (block key 30).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a press forming apparatus for performing press working on metal panel parts for vehicles and the like.

[0002]

2. Description of the Related Art Heretofore, there has been known a press forming apparatus which employs a rotary cam mechanism as a press forming apparatus for bending a panel-shaped work. In this rotary cam mechanism, a cylindrical rotary cam is assembled to a lower die holder provided in a lower die of a press molding device so as to be rotatable around its axis, and a part of the outer peripheral surface of the rotary cam is formed. It is received by a backup punch fixed to the lower mold holder. In the forming operation, when the work is set on the rotary cam and the backup punch and the upper die of the press forming apparatus is lowered, the slide cam provided on the upper die is fixed to the rotary cam. It moves along the guide plate in a direction intersecting the descending locus of the upper die. This makes it possible to bend the work to a negative angle, but the formed work can be easily removed from the lower mold side by rotating the rotary cam to its standby position.

Depending on the shape of the work, a plurality of rotary cam mechanisms may be continuously arranged and used.
As one example, a technique disclosed in Japanese Patent Publication No. 8-256 is known. In this technique, an arc curve portion of a target work is divided into linear portions that can be machined by one rotary cam mechanism, and individual rotary cam mechanisms are arranged in these divided portions.

[0004]

However, since the rotary cam mechanisms described above are independent of each other, the backup punches of the rotary cam mechanisms are also fixed to the respective lower mold holders with bolts and knock pins. Absent. Therefore, if the load applied to the rotary cams of the respective rotary cam mechanisms differs individually depending on the molding conditions, there will be a slight difference in the rotational position of the rotary cams adjacent to each other or the amount of deflection of the backup punch in each rotary cam mechanism. As a result, a step is formed between the adjacent rotary cam and the backup punch, which causes a damage to the surface of the work.

SUMMARY OF THE INVENTION An object of the present invention is to provide a rotary cam mechanism in which a plurality of rotary cam mechanisms are arranged in a row. Another object of the present invention is to eliminate the difference in the amount of bending between the backup punches, to prevent the occurrence of a step between the adjacent rotating cams and the backup punches, and to prevent the surface of the work from being damaged.

[0006]

According to the first aspect of the present invention,
A configuration in which a cylindrical rotary cam is rotatably mounted around an axis of the lower die holder, and a part of the outer peripheral surface of the rotary cam is received by a backup punch fixed to the lower die holder. A press forming apparatus using a plurality of rotary cam mechanisms arranged in a row, wherein backup punches adjacent to each other in each of the rotary cam mechanisms are connected to each other by connection members.

Since the backup punches of the adjacent rotary cam mechanisms are connected to each other by the connecting members as described above, the load applied to the rotary cams of each rotary cam mechanism is different depending on molding conditions. In addition, there is no deviation in the rotation angle of each rotary cam and no difference in the amount of bending of each backup punch. As a result, the step between the adjacent rotary cam and the backup punch is maintained at almost zero, and the surface of the work is prevented from being damaged.

[0008]

Embodiments of the present invention will be described below. FIG. 1 is a sectional view showing a part of the press forming apparatus. Rotary cam mechanism 10 shown in this drawing
Is mainly constituted by a lower mold holder 14, a backup punch 16, and a cylindrical rotating cam 18. The lower die holder 14 is a lower die substrate 1 of a press device.
2, and the lower die holder 14 has an arc-shaped support surface 15 opened at the upper surface thereof. The rotating cam 18 is rotatably supported on the support surface 15 around its axis.

The backup punch 16 is fixed to the lower die holder 14 with bolts and knock pins (both not shown) while receiving a part of the outer peripheral surface of the rotary cam 18. The rotating cam 18 has two surfaces that are partially cut out and are substantially orthogonal to each other. A guide plate 19 is fixed to one surface, and a molding portion 18a is formed on the other surface. I have. A panel-shaped workpiece 40 to be bent is set on the rotating cam 18 and the backup punch 16. The work 40 has a portion that has already been processed in the previous step, and this portion can be received by the uneven surface 17 of the backup punch 16.

[0010] The upper mold holder 20 of the press molding apparatus includes:
The slide cam 22 is slidably mounted in the direction of arrow A in FIG. A formed tip 24 having a shape corresponding to the formed portion 18a of the rotary cam 18 is provided at an end of the slide cam 22.
Are fixed, and the molding portion 18a and the molding tip 24 are fixed.
Thus, the work 40 can be bent. On the other hand, the lower surface of the pad 26 has a shape corresponding to the uneven surface 17 of the backup punch 16, and can be brought into contact with the uneven surface 17 while sandwiching the work 40 therebetween.

FIG. 2 is a plan view showing an example of use of the rotary cam mechanism 10 together with a work 40. In the case where the processed portion is a continuous curve like the work 40 shown in this drawing, the curved portion is divided into four linear portions that can be processed by one rotary cam mechanism 10 (divided into four parts), and , Rotary cam mechanisms 10A to 10D are continuously arranged.

FIG. 2 and the aforementioned rotary cam mechanisms 10
As is apparent from FIG. 3 in which one of A to D is shown in a perspective view, the backup punches 16 adjacent to each other in each of the rotary cam mechanisms 10A to 10D are connected by a block key 30 (connection member). . Accordingly, even when the thrust load applied to the rotary cam 18 in the direction indicated by the arrow B in FIG. 1 during the processing of the workpiece 40 described below differs among the rotary cam mechanisms 10A to 10D individually, The amount of deflection is the same.

When the work 40 is processed by the press forming apparatus, the rotary cam mechanisms 10A to 10D are used.
The work 40 is set on each of the rotary cams 18 and the backup punch 16 in the above. At this time, as already described, the portion of the work 40 already processed in the previous process is the uneven surface 1 of the backup punch 16.
Set to 7. In this state, the rotary cam mechanisms 10 </ b> A to 10 </ b> A
By driving a 10D air cylinder (not shown), etc.
The rotating cam 18 is rotated counterclockwise in FIG. 1 with respect to the lower mold holder 14 and the backup punch 16,
Set at a predetermined rotation position.

With the lowering of the upper die of the press forming apparatus, the pad 26 is moved to the uneven surface 17 of the backup punch 16.
The work 40 of the part received by the above is pressed down from above, and the slide cam 22 is
Then, the upper die moves along a guide plate 19 fixed to the rotating cam 18 in a direction (rightward in FIG. 1) intersecting with the vertical downward locus of the upper die. Thus, the workpiece 40 is bent at a negative angle by the forming portion 18a of the rotary cam 18 and the forming tip 24 of the slide cam 22 in each of the rotary cam mechanisms 10A to 10D, and the forming is completed at the bottom dead center of the upper die.

After the molding is completed, the rotary cams 18 of the rotary cam mechanisms 10A to 10D are rotated in the clockwise direction in FIG. 1 in reverse to the above, and stopped at a predetermined standby position in parallel with the rise of the upper mold. By rotating the rotary cam 18 to the standby position in this manner, the formed workpiece 40 can be easily removed from the forming part 18a of the rotary cam 18 even if the workpiece 40 is bent at a negative angle as described above. Can be.

At the time of the above-mentioned molding, the thrust load indicated by the arrow B in FIG. It may be different depending on the rotating cams 18 of 10A to 10D. Due to this, each rotating cam 1
If there is a difference between the rotation angle of 8 and the amount of deflection of each backup punch 16, the surfaces a and b of the work 40 shown in FIG. 1 may be damaged.

However, in this embodiment, as described above, in each of the rotary cam mechanisms 10A to 10D, the adjacent backup punches 16 are connected to each other by the block key 30, so that the rotation angle of each of the rotary cams 18 and The difference in the amount of deflection of the backup punch 16 is eliminated, and the step between them is maintained at almost zero, thereby preventing the surface of the work 40 from being damaged.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a part of a press molding apparatus.

FIG. 2 is a plan view showing a use example of a rotary cam mechanism together with a work.

FIG. 3 is a perspective view showing one of the rotary cam mechanisms.

[Explanation of symbols]

 10 Rotary cam mechanism 14 Lower mold holder 16 Backup punch 18 Rotating cam 30 Block key

Claims (1)

[Claims] 1. A cylindrical rotary cam is rotatably mounted around an axis of a lower die holder, and a part of the outer peripheral surface of the rotary cam is received by a backup punch fixed to the lower die holder. A press forming apparatus using a plurality of rotary cam mechanisms having a configuration that is continuously arranged, wherein backup punches adjacent to each other in each of the rotary cam mechanisms are connected to each other by a connection member. A press forming apparatus characterized by the above-mentioned.