JPS63108921A - Drawing die device for thin plate like work - Google Patents

Abstract

PURPOSE:To avoid to cause on a work the traction part not coming into contact with a die and to prevent the generation of a wrinkle by energizing a blank holder with its springing toward the upper part and locating it upper than the movable punch in a natural state. CONSTITUTION:When an upper die 1 is descended, a holder face 9 is abutted to the blank part 7 of a work 3 and the blank part 7 is pinched between a holder face 9 and blank holder 14. With further descent of the upper die 1 the work 3 is worked by a forming face 8 and 1st and 2nd movable punches 12, 13 and after a flat part 4 and a 2nd crest part 6 being formed a 1st crest part 5 is formed by a fixed punch 11 and the forming face 8 according to the descent of the 1st and 2nd movable punches 12, 13. In this case, since the work 3 is pinched by the 1st and 2nd movable punches 12, 13 and the forming face 8 of the upper die 1 at both sides of the 1st crest part 5 no traction part is caused on the work 3 at the part abutting to the face of the die nor any drawing wrinkle is caused.

Description

Detailed Description of the Invention A1 Objective of the Invention +l) Industrial Field of Application The present invention involves drawing a thin plate-like workpiece to form a flat part in the center and an upwardly protruding part located outside the flat part. and a second peak that is raised upward outside the first peak and is at approximately the same level as the flat part with a smaller protrusion than the first peak. This invention relates to a drawing die device for thin plate-shaped workpieces.

(2) Conventional technology Conventionally, in such an apparatus, after holding the outer edge of the workpiece, the flat part, the first peak part and the second peak part are formed at once, or the first peak part is drawn and then the flat part is formed. It is common to mold the portion and the second mountain portion.

(3) Problems to be Solved by the Invention However, with the above-mentioned conventional method, drawing wrinkles occur on the workpiece at the tensile part that does not come into contact with the mold during drawing of the first mountain part, and these wrinkles occur even when forming is completed. Wrinkles may not be removed and the product may lose its marketability. This tendency is especially common when drawing workpieces made of relatively soft materials such as aluminum plates, and even if wrinkles can be crushed,
The shape of the wrinkles remains.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a drawing die device for thin plate-like workpieces that prevents the occurrence of wrinkles.

B1 Structure of the Invention (Means for Solving Problems 11) The present invention comprises a molding surface having a shape corresponding to the upper surface of the flat portion, the first ridge portion, and the second ridge portion, and a holder surface continuous to the outer edge of the molding surface. an upper mold which can be raised and lowered by having a lower surface; a fixed punch fixedly disposed below the upper mold to form the first mountain part in cooperation with the molding surface; a flat part which cooperates with the molding surface; a first movable punch which is disposed so as to be movable up and down inside the fixed punch to form a molding surface and which is elastically biased upward so as to protrude above the fixed punch in a natural state; The second movable punch is arranged so as to be movable up and down outside the fixed punch in order to cooperate with each other to form the second mountain part, and in a natural state, the second movable punch is arranged upwardly so as to be at almost the same level as the first movable punch which is in its natural state. A second movable punch which is elastically energized; is disposed so as to be movable up and down outside the second movable punch in order to cooperate with the holder surface to hold the outer edge of the workpiece under pressure, and in a natural state, and a blank holder elastically biased upward so as to protrude above the first and second movable punches in a state.

(2) Effect When the outer edge of the workpiece is placed on the blank holder and the upper die is lowered, the outer edge of the workpiece is first held between the holder surface and the blank holder, and as the upper die is further lowered, the first and second The movable punch and the molding surface of the upper mold form a flat part and the second peak part on the same level, and as the upper mold further descends, the fixed punch and the molding surface mold the first peak part.

Therefore, the workpiece does not have any tensile parts that do not contact the mold (and the generation of wrinkles is also prevented).

(3) Example Hereinafter, an example of the present invention will be explained with reference to the drawings. First, in FIG. A thin metal workpiece 3 is drawn by the cooperation of the lower die 2 and the upper die 1.

That is, in FIG. 2, the workpiece 3 has a flat part 4 at the center, a first ridge 5 located outwardly surrounding the flat part 4, and a second ridge 5 located outside the first ridge 5. It is drawn to have a first peak part 6 and a first peak part 5.
The second ridge portion 6 has a relatively large amount of bulge and is bulged upward from the outer edge of the flat portion 4, and the second ridge portion 6 has a bulge amount smaller than the first ridge portion 5 so as to be at almost the same level as the first ridge portion 4. The outer edge of the mountain portion 5 bulges upward. Furthermore, a blank portion 7 is provided outside the second peak portion 6, that is, at the outer edge of the workpiece 3, to be cut out after drawing completion.

The upper mold 1 is driven up and down by a lifting drive means (not shown), and its lower surface corresponds to the upper surfaces of the flat part 4, the first peak part 5, and the second peak part 6 after the drawing process of the workpiece 3. A molding surface 8 having such a shape and a holder surface 9 connected to the outer edge of the molding surface 8 corresponding to the blank portion 7 of the workpiece 3 are formed. Furthermore, the molding surface 8 and the holder surface 9 are coated with a synthetic resin.

The lower mold 2 includes a fixed base 10, a fixed punch 11 fixed on the base 10 to cooperate with the molding surface 8 of the upper mold 1 to form the first peak 5, and a molding surface 8. A first movable bunch 12 is arranged to be movable up and down inside the fixed punch 11 in order to cooperate with each other to form the flat part 4, and a second movable bunch 12 cooperates with the molding surface 8 to form the second mountain part 6.
A second movable punch 13 is arranged to be movable up and down outside the fixed punch 11 to form a blank part 7 of the workpiece 3 in cooperation with the holder surface 9.
Blank holder 1 is arranged to be movable up and down on the outside of 3.
4, and the upper surfaces of the fixed punch 11, the first movable punch 12, the second movable punch 13, and the blank holder 14 are coated with synthetic resin.

The first movable punch 12 is supported by a plurality of cushion pins 15 that vertically move through the base IO, and in a natural state is located above the fixed punch 11 and is fired upward. energized. Further, the second movable punch 13 is supported by a cushion pin 16 that passes through the base 10 in a vertically movable manner, and is directed upward so as to be at approximately the same level as the first movable punch 12 in its natural state. The bullet is energized. Further, the blank holder 14 is resiliently biased upward by a gas cushion 17 interposed between it and the base 10, and the blank holder 14 is in a natural state without applying any external force. It is located above certain first and second movable punches 12 and 13.

Next, to explain the operation of this embodiment, when drawing the work 3, as shown in FIG. 1, the work 3 is placed on the lower mold 2 with the upper mold 1 and the lower mold 2 separated. do. That is, since the blank holder 14 is at the uppermost position in the lower mold 2, the blank portion 7 at the outer edge of the workpiece 3 is placed on the blank holder 14.

Next, when the upper die l is lowered, the holder surface 9 first comes into contact with the blank part 7 of the workpiece 3, and the blank part 7 of the workpiece 3 contacts the holder surface 9 and the blank holder 1 as shown in FIG.
It is sandwiched between 4.

When the upper mold 1 is further lowered in this state, as shown in FIG. 4, the molding surface 8 and the first and second movable punches 12.
After the workpiece 3 is processed by the first and second movable punches 12.1 and the flat part 4 and the second peak part 6 are formed, the first and second movable punches 12.1
3 descends, the first peak portion 5 is formed by the fixed punch 11 and the forming surface 8.

At this time, the workpiece 3 is pressed between the first and second movable punches 12.13 and the molding surface 8 of the upper mold 1 on both sides of the first peak 5, and the portions that do not come into contact with the mold are In this case, no tensile parts are generated in the workpiece 3, and no drawing wrinkles are generated.

When the upper mold 1 descends to the lowest position as shown in FIG.
It is molded into a shape having a peak 5 and a second peak 6.

C0 Effects of the Invention As described above, the device of the present invention has a molding surface having a shape corresponding to the upper surface of the flat portion, the first peak portion, and the second peak portion, and a holder surface connected to the outer edge of the molding surface on the bottom surface. an upper mold that can be raised and lowered; a fixed punch fixedly arranged below the upper mold to form the first mountain part in cooperation with the molding surface; fixed to form a flat part in cooperation with the molding surface; a first movable punch which is disposed so as to be vertically movable inside the punch and which is resiliently biased upward so as to protrude above the fixed punch in a natural state; It is disposed so as to be movable up and down outside the fixed punch to form two peaks, and is elastically biased upward to be at approximately the same level as the first movable punch in its natural state. a second movable punch;
The second part cooperates with the holder surface to hold the outer edge of the workpiece under pressure.
a blank holder disposed outside the movable punch so as to be vertically movable and elastically biased upward to protrude above the first and second movable punches which are in a natural state; ; After the outer edge of the workpiece is held between the holder surface and the blank holder, a flat part and a second peak part are formed according to the lowering of the upper mold, and the first peak part with a relatively large amount of protrusion is Since both sides are held and finally drawn, it is possible to avoid the generation of tensioned parts that do not come into contact with the mold, and to prevent the occurrence of wrinkles as much as possible.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Figure 1 is a vertical sectional side view of the apparatus of the present invention, Figure 2 is a vertical sectional view of a workpiece, and Figures 3, 4, and 5 show the drawing process. FIG. 2 is a vertical sectional side view corresponding to FIG. 1 for sequentially explaining.

Claims (1)

[Claims] A thin plate-shaped workpiece is drawn and formed to form a flat part in the center, a first peak part located outside the flat part and raised upward, and a first peak part with a smaller amount of protrusion than the first peak part. In a drawing die device for a thin plate-like workpiece, the flat part, the first peak part, and the second peak part are formed to form a second peak part that protrudes upward on the outside of the part and is substantially on the same level as the flat part. an upper mold having a molding surface having a shape corresponding to the upper surface and a holder surface connected to the outer edge of the molding surface on the lower surface and which can be raised and lowered;
A fixed punch is fixedly disposed below the upper die to form a peak; a fixed punch is disposed so as to be movable up and down inside the fixed punch to form a flat part in cooperation with the forming surface; a first movable punch that is resiliently biased upward to protrude above the fixed punch; a second movable punch that cooperates with the molding surface;
The first punch is arranged to be movable up and down outside the fixed punch to form a peak, and is in a natural state.
a second movable punch that is elastically biased upward to be at almost the same level as the movable punch; a blank holder which is movably arranged and biased upward so as to protrude above the first and second movable punches which are in a natural state; A drawing die device for thin plate workpieces.