JP2000233232A - Press forming device for flange - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a rotation angle and a press stroke of a rotary punch that control the forming of the flange part, as much as possible in order to cope with high speed production of a transfer press, etc. SOLUTION: While rotating and driving a rotary punch 13 by a slide cam 5 of an upper die side, by driving the slide cam 5 with a collapse punch 12, a flange part F2 is bent-formed with a shape angle. Even when the rotary punch 13 is reversed after the flange part F2f is formed, since a flange forming part 13a is not completely come out from the flange part F2, the whole collapse punch 12 is retreated by a hydraulic cylinder 14.

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 forming a flange, and more particularly to a press forming apparatus having an acute angle formed on an end portion of a panel previously drawn and formed into a predetermined shape as typified by an outer panel of an automobile. The present invention relates to a press forming apparatus for forming a so-called inverse-shaped flange portion which is caught in a pressing direction.

[0002]

2. Description of the Related Art A front fender panel W of an automobile as shown in FIGS. 4 and 5 has a flange portion F1 formed on an upper edge thereof for connection with a hood ridge panel, and a wheel arch portion Wa. The flange portion F2 is also formed in a portion corresponding to. In particular, since the flange portion F2 of the wheel arch portion Wa is formed at an acute angle θ with respect to the base material surface, the flange portion F2 is formed by, for example, a collapse cam structure disclosed in Japanese Utility Model Laid-Open No. 185019/1984. In addition to the press forming apparatus described above, a press forming apparatus having a rotary punch structure as shown in FIG. 6 is used.

The forming of the flange portion F2 by the rotary punch structure press forming apparatus can be understood as a process in which a part of the collapse cam (punch) itself in the collapse cam structure is replaced with a rotary rotary punch 6. As shown in FIG. 6, a front fender panel (hereinafter referred to as a work) W drawn in advance.
Is pressed and restrained by the punch 2 on the lower die 1 side and the pad 4 on the upper die 3 side, and the slide cam 5 on the upper die 3 side is integrated with the rotary punch 6 as the upper die 3 is lowered. 7 to rotate the rotary punch 6. When the drive plate 7 contacts the drive cam surface 2a of the punch 2, the rotary punch 6
Then, the slide cam 5 is slid and driven by the drive cam surface 2a, and the flange portion F2 is bent by cooperation of the slide cam 5 and the rotary punch 6.

When the upper die 3 is raised as shown in FIG. 7, the rotary punch 6 reversely rotates by the force of a return spring (not shown), whereby the flange forming portion 6a of the rotary punch 6 is formed. Since the workpiece W comes out of the flange portion F2 having the inverse shape and its interference is avoided, the work W can be taken out from the rotary punch 6 upward.

[0005]

In the press forming apparatus having such a rotary punch structure, it is easy to remove the flange forming portion 6a from the formed flange portion F2, but the length L of the flange portion F2 (see FIG. 5), the rotation angle of the rotary punch 6 required for extracting the flange forming portion 6a increases, and as a result, the press stroke S shown in FIG. 7 increases. Even when applied, there is naturally a limit in increasing the operating speed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and a press forming apparatus based on a conventional rotary punch structure and capable of reducing the rotation angle of the rotary punch and hence the press stroke. It is something to offer.

[0007]

According to the first aspect of the present invention, an upper end of a work is cooperated with an upper die and a lower die while a work is pressed and restrained by a pad on an upper die side and a lower die. Press forming apparatus for bending and forming a flange portion at an acute angle to the upper portion, wherein the upper die has an upper holder, a pad elastically supported by the upper holder so as to be vertically movable, and also slidably supported by the upper holder. And a slide cam driven by sliding contact with the drive cam surface of the lower die, while the lower die is mounted on the lower holder, and a flange portion after molding and a flange portion are formed. A collapsed punch that is slid at a predetermined timing to release the engagement with the rotary punch, and is rotatably supported by the collapsed punch around the center of a circle whose tangent is the length of the flange to be formed. Sa Rutotomoni, wherein are rotary drive in accordance with the vertical movement of the slide cam is characterized in that it is composed of a rotary punch which governs the forming of the flange portion directly in cooperation with the slide cam.

[0008] The invention described in claim 2 is the first invention.
The collapse punch in the invention described in (1) is characterized in that it is slid and driven by the operation of a hydraulic cylinder such as hydraulic or pneumatic.

Therefore, according to the first aspect of the present invention,
The forming of the flange portion by the cooperation of the slide cam and the rotary punch is basically performed under the same behavior as the conventional rotary punch structure. When the press stroke is reduced and the rotation angle of the rotary punch is reduced, even if the rotary punch is reversed to come out of the formed flange portion, the flange formed portion of the rotary punch is completely removed from the flange portion. I can't get out.
Therefore, by rotating the rotary punch together with the collapse punch after the rotation of the rotary punch, the flange forming portion of the rotary punch completely comes out of the formed flange portion for the first time. Thus, even when the present invention is applied to, for example, a transfer press, it becomes possible to easily perform the flange processing without impairing the high-speed productivity.

Here, as in the invention according to claim 2,
If the collapse punch slide operation is performed by a hydraulic cylinder such as an air cylinder or a hydraulic cylinder, only the operation timing of the collapse punch need be adjusted, and the slide operation of the collapse punch itself is a press operation. Does not hinder the high-speed operation of the transfer press.

[0011]

According to the first aspect of the present invention, the radius of rotation and the angle of rotation of the rotary punch and thus the press stroke can be made much smaller than those of the prior art, so that the productivity of the transfer press and the like is particularly excellent. In the case where the present invention is applied to a press machine that has been used, there is an effect that high-speed productivity of press working for forming an inverse-shaped flange portion can be maintained.

According to the second aspect of the present invention, the sliding operation of the collapse punch is performed by the hydraulic cylinder, so that the sliding operation of the collapse punch does not depend on the pressing operation of the press machine itself. Therefore, there is an effect that the productivity can be further improved.

[0013]

1 to 3 show a preferred embodiment of the present invention. The structure of the lower die is different from that of the conventional structure shown in FIGS.

As shown in FIG. 1, the upper die 3 is provided with an upper holder 8.
And a pad 4 supported by the upper holder 8 so as to be vertically movable.
And a slide cam 5 also slidably supported on an inclined slide guide surface 8a of the upper holder 8. The pad 4 is moved upward by a predetermined amount relative to the upper holder 8 so that a downward elastic force is applied by a fluid-filled elastic means 9 serving as a pressure source, and the slide cam 5 is described later. The slide operation is performed within the range of the stroke S1 by sliding contact with the drive cam surface 12a. The slide cam 5 has an inclined cam surface 5a, and a return force in the direction of arrow a is applied by a return spring (not shown).

On the other hand, the lower die 10 includes a lower holder 11, a collapse cam type collapse punch 12 slidably supported on an inclined slide guide surface 11 a of the lower holder 11, and a rotary provided on the collapse punch 12. And a punch 13. Collapse punch 13
Has an inclined drive cam surface 12a, and slides within the range of the stroke S2 according to, for example, the expansion and contraction operation of the hydraulic cylinder 14. The rotary punch 13 is rotatably supported by a cylindrical guide surface 12b formed in the center of the collapse punch 12, and has a tip end adjacent to the concave portion 15 having a substantially rectangular cross section. Flange F2 in cooperation
In addition to the formation of a flange forming portion 13a which directly controls the molding, a drive plate 7 is integrally fixed to the other end. The rotary punch 13 is rotatable forward and reverse between a forward rotation limit position shown in FIG. 1 and a reverse rotation limit position shown in FIG. 2, and its rotation center P is approximately tangent to the flange portion F2 to be formed. The return force in the direction of arrow b is applied to the rotary punch 13 by a return spring (not shown).

According to the press-forming apparatus having the above-mentioned construction, as shown by the broken line Q in FIG.
After positioning on the upper mold 2, the upper mold 3 is lowered. At this time,
Since the hydraulic cylinder 14 is in the extended state, the collapse punch 12 is held at the ascending limit position along the slide guide surface 11a. That is, FIG. 3 shows a state in which the upper die 3 has risen after the molding of the flange portion F2, but before the molding of the flange portion F2, the components of the press die are in the same state as in FIG.

When the upper die 3 descends, first, the cam surface 5a of the slide cam 5 comes into contact with the drive plate 7 on the rotary punch 13 side (the same state as in FIG. 2), and the slide cam 5 contacts the drive plate 7. The rotary punch 13 gradually rotates forward by the contact, and the drive plate 7 contacts the drive cam surface 12a of the collapse cam 12, whereby the rotary punch 13 is finally positioned at the forward rotation limit position shown in FIG. And the rotary punch 13
The pad 4 comes in contact with the work W and restrains it with pressure slightly later than the position of the pad 4 is positioned at the forward rotation limit position.

As described above, the state in which the drive plate 7 is in contact with the drive cam surface 12a is the state in which the cam surface 5a of the slide cam 5 is indirectly in contact with the drive cam surface 12a via the drive plate 7. From meaning,
When the upper mold 3 is still lowered from this state, the slide cam 5 is driven by the drive cam surface 12a and relatively moves upward along the slide guide surface 8a, but the tip thereof has a concave portion on the rotary punch 13 side. Enter 15. As a result, the cooperation between the rotary punch 13 and the slide cam 5 causes the flange portion F2 to be bent and formed at an acute angle to the base material as shown in FIG.

When the upper die 3 reaches the bottom dead center due to the bending of the flange portion F2 and the upper die 3 starts to rise again from the bottom dead center, the drive plate 7 on the rotary punch 13 side is moved as shown in FIG. By gradually moving away from the drive cam surface 12a of the collapse punch 12, the rotary punch 13 performs a reverse rotation operation. Even if the rotary punch 13 reaches the reverse rotation limit position, the flange forming portion 13a of the rotary punch 13 does not completely come out of the flange portion F2 just formed, and the flange portion F2 is still caught in the pressing direction. In a so-called inverse state (a state shown in FIG. 2).

Then, after the slide cam 5 is completely separated from the drive plate 7, the hydraulic cylinder 14 contracts as shown in FIG. 3, and the rotary punch 13 moves together with the collapse punch 12 in the Slides to the position, and the flange part F
The flange forming portion 13a of the rotary punch 13 comes out of 2 and the relationship of the inverse is released. Thereafter, the work W can be taken out from the lower mold 10 by pushing up the whole work W directly above by a lifter or the like (not shown).

As described above, according to the present embodiment, the structure in which the rotary punch 13 is attached to the slide-type collapse punch 12 makes it clear from the comparison with FIG. The rotation angle can be greatly reduced, and as a result, the press stroke for driving the rotary punch 13 to rotate can also be significantly reduced as compared with the conventional one (stroke S in FIG. 7). Become.

Although the above embodiment has been described with reference to the example of flange processing of a front fender panel, it goes without saying that the present invention can be applied to flange processing of various panels other than the front fender panel.

[Brief description of the drawings]

FIG. 1 is a view showing a preferred embodiment of a press molding apparatus according to the present invention, and is an explanatory sectional view showing a state when an upper die reaches a bottom dead center.

FIG. 2 is an explanatory cross-sectional view showing a state when the upper die has risen by a predetermined amount from the state of FIG. 1;

FIG. 3 is an explanatory sectional view showing a state where the upper die is further raised from the state of FIG. 2 and the slide cam is separated from the drive plate;

FIG. 4 is an explanatory front view showing an example of a front fender panel of an automobile.

FIG. 5 is a sectional view taken along the line AA of FIG. 4;

FIG. 6 is an explanatory sectional view showing an example of a conventional press forming apparatus having a collapsed cam structure.

FIG. 7 is a sectional explanatory view showing a state when the upper die has risen from the state of FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 3 ... Upper mold 4 ... Pad 5 ... Slide cam 7 ... Drive plate 8 ... Upper holder 10 ... Lower mold 11 ... Lower holder 12 ... Collapse punch 12a ... Drive cam surface 13 ... Rotary punch 13a ... Flange forming part 14 ... Hydraulic cylinder ( Fluid pressure cylinder) F2: Flange W: Work (front fender panel)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B21D 37/08 B21D 37/08

Claims (2)

[Claims] 1. A press for bending and forming a flange portion at an end of a work at an acute angle in cooperation with the upper and lower dies while pressing and restraining the work with a pad on an upper die side and a lower die. A molding device, wherein the upper die is in sliding contact with an upper holder, a pad elastically supported by the upper holder so as to be vertically movable, and a drive cam surface of the lower die which is also slidably supported by the upper holder. The lower die is mounted on the lower holder, and a predetermined shape is set to release the engagement between the molded flange portion and the rotary punch described later. A collapsed punch that is slid and driven at a timing, and is rotatably supported by the collapsed punch about the center of a circle having a tangent to the length of the flange to be formed, and the slide cam is moved up and down. Cooperating flanging press-molding apparatus characterized by being composed of a rotary punch which governs the forming of the flange portion directly by the driven rotating said slide cam in accordance with the. 2. The flange forming press forming apparatus according to claim 1, wherein the collapse punch is slid by an operation of a hydraulic cylinder.