JPH01162526A - Press forming method - Google Patents

Abstract

PURPOSE:To form an inverted flange on tow adjacent sides with high accuracy by providing a projecting seat on a corner part of a work in which both flanges intersect with each other, and also, providing a bend part on the peripheral part of one side of the work and executing the flange bending by the upper and the lower bending edges, while holding a general surface containing the projecting seat by a pad. CONSTITUTION:A projecting part 33 is formed in a corner part of a work 22 corresponding to a part where an inner flange 11 and an outer flange 13 intersect with each other, a projecting seat 31 is provided on its apex part, and also, a bend part 34 is formed in the peripheral part which becomes a bend part of the outer flange 13. Also, in the corner part of the work 22, a notch 35 is provided, and between the projecting seat 31 and the bend part 34, a gap S is formed. In this state, when said work 22 is placed on the lower die bending edge 21 and held by a pad 23, and the upper die edge 24 is allowed to descend, the bend part 34 is bent in the anti-press direction, and the outer flange 13 is formed. Simultaneously, the other peripheral part being adjacent to the bend part 34 is brought to flange bending in the press direction, and the inner flange 11 is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a press-forming method, and more particularly to a method for press-forming oppositely bent flanges on two adjacent sides.

(Prior Art) An example of a molded product having this type of bent flange is an inner side roof panel (hereinafter simply referred to as an inner panel) arranged inside a quarter panel of an automobile. As shown by reference numeral 1 in FIGS. 10 to 14, storage space 4 is provided inside the quarter panel 2 in a pair on the left and right, forming a trunk room 3 together with the lower bag 6, and providing a storage space 4 for tools and the like between the quarter panel 2 and the quarter panel 2. The 0-inch panel l to be formed (FIG. 11) is made by spot welding the inner flange 11 provided at the upper end to the quarter panel 2.
2) and a flat portion 12 provided at the tip (front of the vehicle) is fixed to the quarter wheel house panel 5 by spot welding. Inner panel 1 again. In order to improve safety and strength, an outer flange 13 is provided at the rear end (free end).

The inner 7 flange 11 has to be directed towards the inside of the vehicle in order to be spot welded to the quarter panel 2, while the outer flange 13 has to be directed towards the outside of the vehicle in order to avoid getting caught. As such, the in-number panel l requires oppositely oriented flanges 11, 13 on two adjacent sides.

The outer flange 13 is made of a bent piece that forms a groove 14 in relation to press forming, which will be described later.
4 protrudes into the re-drink room 3 from the general surface A by a height h (usually 7 to 10+ am), which causes the space of the trunk room 3 in the vehicle width direction to be narrowed.

In order to obtain the outer panel l by press forming, conventionally, first, primary forming including outline cutting and drawing is performed, followed by secondary forming including flange bending and hole punching. That's what I was doing.

More specifically, the outer shape and the plate surface shape are determined by the primary molding, and the inner flange 11 and the outer flange 13 are simultaneously bent in the secondary molding of this primary molded product, and the holes 15 are bent simultaneously. .15... (Fig. 13) is also performed simultaneously. The bending of the outer flange 13
As shown in FIGS. (a) and (b), a workpiece (primary molded product) 22 is placed on the lower mold curved blade 21 and held down with a pad 23, and a groove is formed in the lower mold curved blade 21. The upper mold curved blade 24 is inserted into 21a, and the end of the workpiece is bent into a 0-shaped cross section.
A groove 14 or outer flange 13 is formed. At this time, as shown in FIG.
By leaving the part a as it is and pressing this part a with the pad 23, the ridgeline of the inner flange 11 which is to be bent at the same time is clearly exposed.

By the way, the presence of the groove 14 causes the space in the trunk room 3 in the vehicle width direction to be narrowed as described above, so if it can be omitted, it will be extremely advantageous in terms of space. Therefore, as shown in FIG. 18, for example, a cushion 25 is provided inside the lower mold curved blade 21a, and this cushion 25 and the upper mold curved blade 24 are used to hold the workpiece.
While holding the workpiece 22, lower the workpiece 22 and press in the press direction P.
The outer flange 13 is formed by bending the flange in the opposite direction (anti-pressing direction), or as shown in FIG. Place one end of the work 22 on the pad 23 and bend the flange directly in the opposite direction to the press to form the outer flange 1.
It is conceivable to adopt a method of forming 3.

(Problems to be Solved by the Invention) However, the method using the cushion 25 (first method)
According to Fig. 6), during molding, the cushion 25 descends, making it impossible to punch holes and process the inner flange 11 at the same time. This results in a significant increase in manufacturing costs. On the other hand, the pad 2
According to the method of direct flange bending according to No. 3 (FIG. 17), the workpiece 22 becomes inclined as shown by the broken line, and when pressed with the pad 23, the workpiece becomes misaligned or deformed. The quality of the molded product will be significantly impaired, and molding of the inner flange 11 will also become difficult.

The present invention has been made in view of the above-mentioned conventional problems.
without increasing the press forming process or deteriorating formability.
It is an object of the present invention to provide a press forming method that can effectively bend a flange in the opposite direction.

(Means for Solving the Problems) A feature of the present invention for solving the above problems is that in the method of press-forming bending flanges in opposite directions on two adjacent sides, A convex seat protruding in the counter-pressing direction is provided at the corner of the corresponding workpiece, and a bending part that is bent in the counter-pressing direction is provided on the periphery along one side of the workpiece, and the general surface including the convex seat is provided. The key point is that the upper and lower curved blades work together to bend the flange while holding it down with a pad.

(Function) In the press forming method having the above configuration, by providing the convex seat, the parting portion of both flanges can be effectively pressed by the pad, and the ridge line of the bent flange can be clearly seen. Furthermore, by providing the bending portion in advance on the workpiece, the workpiece will not be displaced or deformed even when pressed with a pad, and the flange can be bent without forming a groove.

(Example) Hereinafter, an example of the present invention will be described based on the accompanying drawings. This example is intended for the inner side roof panel (inner panel) of an automobile, and in the following figures, the same parts as those shown in Figs. 10 to 17 are given the same reference numerals. , the explanation thereof will be omitted here.

5 to 7 show the inner panel l obtained by the press molding method of the present invention and its assembled state. Outer flange 1 formed at the free end of the inner panel 1
3 rises directly from the general surface, and the conventional groove 14 is omitted.

That is, since the groove 14 is omitted, the space within the trunk room 3 in the vehicle width direction is expanded. Further, a convex seat 31 is provided at the intersection of the outer flange 13 and the inner flange 11 of the inner panel l. This convex seat 31 is formed in advance by primary forming described later, and the outer flange 13 is connected to the convex seat 31 via a local recess 32, and the unidirectional force flange 11 is ! is directly connected to. Note that the height h of the outer 7 flange 13 and the convex seat 31 from the general surface A is higher than that of the conventional groove 14.
and C are the same height (7 to 10t+w).

In order to obtain the inner panel 1 as described above, as shown in FIG. A protrusion 33 is formed at the corner of the corresponding workpiece 22, and the convex seat 31 is provided on the top of the protrusion 33, and a bent part 34 is provided at the circumferential part where the outer flange 13 is bent.
The convex portion 33 and the bent portion 34 that form the press are protruded or bent in a direction opposite to the pressing direction P (FIG. 2). Further, a rectangular notch 35 is provided at the corner of the workpiece 22, and the convex seat 31 and the bent portion 3 facing this notch 35
A predetermined gap s (5 to 1hm) is formed between the end face of 4 and the end face of 4.

Next, as shown in FIGS. 2 and 3, the workpiece 22 is placed on the lower mold curved blade 21 and held down by the pad 23, and the upper mold curved blade 24 is lowered. At this time, the pad 23 is also used to press the convex portion 33 including the convex seat 31 (first
(shaded area in the figure), FIG. 2 is a cross-sectional line L1 including the convex portion 33
(Figure 1).

Fig. 3 shows the holding state at the cross-sectional line L2 of the general surface A (first
Fig. 3 shows the holding state along the curve shown in Fig. 2, and in both cases, only the bent portion 34 protrudes above the stepped portion 21b of the lower mold curved blade 21. Then, as the upper die curved blade 24 descends, the bent portion 34 is bent in the opposite direction to the pressing direction, and as shown in FIG. 4, the outer seven flange 13 is formed. At this time, a local recess 32 is formed in a portion adjacent to the convex portion 33 with the convex portion 33 serving as a wall, but in other portions, the outer flange 13 stands directly up from the general surface. Also, at the same time as bending the flange of the bending portion 34, the same upper mold bending blade 2
4, the other peripheral portion adjacent to the bent portion is flange-bent in the press direction P, and an inner flange 11 is formed there. At this time, since the convex seat 31 is also pressed by the pad 23, the inner flange 11
The ridgeline becomes clear. In addition, in the inner panel 1 formed in this way, the intersection of both flanges is opened due to the presence of the convex seat 31, and as shown in FIG. 7, the spot W can be set up to the end, making it stronger. It can be assembled into.

Incidentally, if the bent portion 34 is simply provided at the circumferential portion of the outer flange 13 as shown in FIG. 8, without providing the convex seat 31 as described above, the bent portion 34
It is not possible to press the inside of the bending line of the inner flange 11 with the pad 23, so that the pressure of the pad 23 is limited to the shaded area in the figure, and the ridge line of the inner flange 11 becomes unclear. This will cause deformation due to shackle. Further, as shown in FIG. 9, if a part a' of the eel side A is simply provided adjacent to the bent part 34, the connecting part C between the part a and the bent part 22a will be left unfilled. This causes wrinkles to occur. In other words, in either case, there is a problem with formability,
It becomes difficult to obtain molded products of good quality.

In addition, in the above embodiment, an example of application to an inner side roof panel arranged inside a quarter panel of an automobile was described, but the molded product to which the present invention is applied is not limited to this, and two adjacent Of course, the present invention can also be applied to other molded products having oppositely bent flanges on the sides.

(Effects of the Invention) As described above in detail, according to the press forming method according to the present invention, the parting portions of both flanges can be effectively pressed by the pad using the convex seat, and The presence of the bent portion can prevent displacement and deformation of the workpiece, and has the effect of allowing flanges facing in opposite directions to be formed on two adjacent sides with high accuracy. In addition, since flange bending can be performed with the upper φ curved blade, it is also possible to perform hole punching at the same time, improving the processing efficiency of press forming, and further eliminating the need for grooving, expanding the range of applications for molded products. However, the present invention has great effects overall.

[Brief explanation of the drawing]

FIG. 1 is a perspective view schematically showing the shape of a workpiece used in the present invention, FIGS. 2 to 4 are cross-sectional views showing an embodiment of the press forming method according to the present invention, and FIGS. 5 to 7 5 shows a molded product (inner side roof panel) obtained by the press molding method of the present invention, FIG. 5 is an assembly diagram, FIG. 6 is a perspective view, FIG. 7 is an enlarged perspective view of main parts, and FIG. Figure 9 and Figure 9 are perspective views illustrating examples of problems when a convex seat is not provided, and Figure 1.
Figures 0 through 14 show conventional inner side roof panels, Figures 10 and 12 are assembly drawings, and Figures 1 and 12 are assembly drawings.
Figure 3 is a perspective view, Figure 14 is an enlarged perspective view of main parts, and Figure 15 is a perspective view.
Figures (a) and (b) are cross-sectional views showing an implementation mode of a conventional press-forming method, and Figs. 16 and 17 are cross-sectional views showing modified examples of the conventional press-forming method. 11... Inner flange, 13... Outer flange 22
... Workpiece, 21 ... Lower mold curved blade 23 ...
Pad, 24...Upper curved blade 31...Convex seat,
34...Bending part Fig. 1 Fig. 5 Fig. 6 Fig. 8 Fig. 10 Fig. 16 (b) Fig. 17

Claims (1)

[Claims] (1) In a method of press-forming bending flanges in opposite directions on two adjacent sides, a convex seat protruding in the opposite pressing direction is provided in advance at the corner of the workpiece corresponding to the area where both flanges intersect, and the workpiece A bending part is provided on the periphery along one side to bend in the opposite direction to the press, and the upper and lower curved blades work together to bend the flange while pressing the general surface including the convex seat with a pad. A press molding method characterized by: