JPS602132B2 - Deep drawing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a deep drawing method employed in hydraulic deep drawing and ordinary deep drawing.

For example, in the hydraulic deep drawing method, as shown in Fig. 1, a pressure chamber 2 provided on the side of a die 1 is filled with a liquid 3, and a blank 4 that has been refinished is placed on the top surface of the die 1 using a blank holder 5. After holding it, push the punch 6 (downward)
This is a processing method that performs deep drawing. In this processing method, high pressure is generated in the pressure chamber 2 by pushing the punch 6, and the blank 4 is strongly pressed against the punch 6. Further, the compressed liquid 3 is forcibly discharged from between the die blanks to the receiving tray 7 side, thereby lubricating the gap between the die blanks. There is no problem if the drawn Arashi-an shape part by such hydraulic deep drawing method is in one place, but for example, as shown in Fig. 2 and Fig. 3, there is no problem.
When molding a product having multiple drawing sections 8 at once, there are the following drawbacks. In other words, since the material is squeezed using the fixed die 1 and punch 6, a sufficient amount of material is not supplied to the center portion 9 of the product between the drawing portions 8, so that the wall thickness of the center portion 9 is reduced. Therefore, a product having a deep drawn portion 8 cannot be obtained. The present invention provides a deep drawing method that can solve the above problems.

The principle of the invention is as follows.

In other words, in products molded using the conventional method, a certain degree of depth is secured by reducing the thickness of the central part 9 of the product, but if you look closely, you will notice that the arrows in Figure 2 As shown, the material also flows from the drawing section 8. In order to actively cause this material flow, the present invention has the following steps:
A mechanical external force is applied from the outer periphery of the blank in the direction in which the material flows. Therefore, when forming parallel drawn parts, the present invention is capable of simultaneously pushing a plurality of punches and moving the blank relative to each other in the direction between the punches. The compressive force that causes compression in the direction of . It is configured to be added to the outer periphery of the blank, and can prevent material flow from the center of the blank to the drawing section, and can actively cause material flow from the outer periphery of the blank to the drawing section. , it is possible to form parallel deep drawn parts without reducing the plate thickness at the center of both drawn parts. Hereinafter, a hydraulic deep drawing method which is an embodiment of the present invention will be explained based on FIGS. 4 to 9.

In FIG. 4 to FIG. 6, the die is fixed at one end, with a partition wall 11 in the center and pressure chambers 12A on both sides.
12B is formed.

Reference numeral 13 indicates the liquid contained in the pressure chambers 12A and 12B.

14 is an elevating body on the press side, and punches 15A and 15B corresponding to the pressure chambers 12A and 12B are vertically provided from the lower surface thereof. 16 is a plank holder disposed outside the punches 15A, 15B, and 17 is a blank.

Reference numerals 18A and 18B are push plates whose inner ends are connected to the outer peripheral portions 17a and 17 of the blank 17 in the direction between the punches 15A and 15B.
It is arranged so as to correspond to the bush.

The thickness of these push plates 18A and 18B is the same as that of blank 1.
7, and is configured to be guided between the lower guide members 19A, 19B attached to the die 1 and the upper guide members 20A, 20B attached to the blank holder 16. . Reference numerals 21A and 21B are push plate holders made by joining both sides of the push plates 18A and 18B from the outer ends, and the guide portions 19A, 20A, 19B, and 20B are connected to each other through spaces 22A and 22A formed in the center.
It will be arranged so that it will guide you.

And the press plate holders 21A, 21B are the punches 15A,
It is configured to be movable so as to apply compressive force to the outer circumferential portions 17a, 17b as 15B is pushed in. Fourth
Figures 6 to 6 show the state before deep drawing.

That is, a blank 17 is placed on the die 10 and held by a blank holder 16. At this time, the inner ends of the push plates 18A, 18B are in contact with the outer peripheral portions 17a, 17b. In this state, lower the elevating body 14 and punch the punch 15.
Push in A and 15B and move on to the desired deep drawing. At this time,
As it narrows down, the push plate holders 21A, 21B move forward, and an external force acts on the plank 17 via the push plates 18A, 18B so that it is compressed from the outer circumferential portions 17a, 17b. The material is forcibly fed (feeded) to the center in the direction between the punches 15A and 15B. In this case, the push plates 18A, 18
The elastic seat wind of B is a problem, but this is the guide section 19A.
, 20A, 19B'20B and press plate holders 21A, 21
This can be solved by a combination configuration with B. By completely narrowing down, the states shown in FIGS. 7 to 9 are obtained. In the embodiment, a manufacturing method having two drawing sections is shown, but it is also possible to draw three or more sections by increasing the number of pressure chambers, punches, etc. As mentioned above, it applies a mechanical external force in the direction in which the material flows.
The effect of this external force is expressed by the following equation.

. =. o+0,1P …………[1}Here, 〇 is the first
This is the blank stress at part E in Figure 0.

o is the stress required to squeeze the blank 17 from the flange portion F, 0 is the additional resistance caused by sliding the blank 17 on the punch seat G, and P is the compressive stress applied to the outer periphery of the blank. That is, by applying a compressive force to the outer periphery of the blank, the stress in the B part is relaxed and it becomes difficult to break, and it becomes possible to draw it deeper. Also the 9th
As shown by the imaginary line in the figure, it is possible to squeeze deeply just by applying compressive force locally. This is the stress necessary to squeeze the blank 17 from the flange part F. This is because o becomes high in this part (dice corner part), so even if compressive force is applied only to this part, 0 in equation '1' can be effectively reduced. As described above, according to the deep drawing method of the present invention, when forming parallel drawn parts, a compression force that compresses the blank in the direction between the punches is applied to the outer peripheral part of the blank while simultaneously pushing a plurality of punches. Because of this, during deep drawing, the material is forcibly fed from the outer circumference side to the center part in the direction between the punches, and multiple drawing parts can be sufficiently filled at the same time without reducing the wall thickness in this center part. It is possible to obtain products that are narrowed down to a certain depth.

Although the present invention can be successfully used in ordinary deep drawing, it is particularly effective when used in hydraulic deep drawing. In other words, in hydraulic deep drawing, there is no contact between the die shoulder and the blank, and the friction between the die and blank is reduced, making it easier to push the material into the die.

[Brief explanation of drawings]

Figure 1 is a vertical cross-sectional view showing the deep drawing of a subordinate column, Figure 2 is a vertical cross-sectional view of the product to be obtained, Figure 3 is a plan view of Figure 2, and Figure 4 is a vertical cross-sectional view of the product to be obtained.
9 to 9 show one embodiment of the present invention, FIG. 4 is a longitudinal sectional front view before deep drawing, FIG. 5 is a sectional view taken along line A-A in FIG. 4, and FIG. 6 is B-B in FIG. -B sectional view, FIG. 7 is a vertical sectional view after deep drawing is completed, FIG. 8 is a CC sectional view in FIG. 7, FIG. 9 is a DD sectional view in FIG. 7, and FIG. It is an action explanatory diagram. 10... Dice, 11... Partition wall part, 12A, 12B
...pressure chamber, 13...liquid, 14...elevating body, 1
5A, 15B... Punch, 16... Blank holder,
17... Blank, 18A, 18B... Push plate, 19
A, 198, 20A, 20B...Guide member, 21A, 2
1B...Press plate holder. Figure 1 Figure 2 Figure 3 Figure 4 Figure 6 Figure 5 Figure 7 Figure 8 Figure 9 Figure 10

Claims (1)

[Claims] 1. When forming the parallel drawn parts, a compression force is applied to the outer circumferential portion of the blank to compress the blanks in directions facing each other in the direction between the punches while simultaneously pushing in a plurality of punches. Deep drawing method.