JPS6257719A - Pess die device - Google Patents

Abstract

PURPOSE:To extremely easily form a die with high accuracy without difficult die sinking and mating work by forming a die form face by transferring the shape of a punch on the hard resin layer which is hardened at room temp. CONSTITUTION:The hard synthetic resin layer 9 that a punch shape is transferred is formed on the recessed part 7 of the die 1 of a press die device. In order to form this resin layer 9, a urethane resin, etc. is filled up by pouring from a filler hole 10 after filling a filler 11 in the gap by setting the die main body 1a and punch 2 in a shut height state. Consequently the resin layer 9 on which the punch shape is transferred is obtd. on the inner face of the recessed part 7. In case of the press the forming is performed with the resin layer 9 effecting the pressing force onto the blank by being compressed by the thickness part of the blank. The die forming face can therefore be formed extremely easily and accurately without troublesome works.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a press mold apparatus for press forming a thin metal plate using a punch and a die.

(Conventional technology) Conventionally, the punches and dies of press equipment are die-sinked from cast iron (FO material) or other metal materials by machining, then finished by hand, and then tested. Corrections were made through alignment work. However, in order to reduce the labor and cost of mold production, rubber punches were used. Filled with die and punch T-manufacturing.

(Problems to be Solved by the Invention) Manual finishing and correction work for die-sinking a die made of cast iron is extremely difficult because it involves machining the inner surface of a recess. Since it is not possible to secure all parts, skill is required, and this is the reason why type gR is expensive. However, with the method using a rubber punch, it is difficult to form into an accurate shape due to the formation of dents in the detailed shape, and concrete dies and punches are not suitable for manufacturing small-scale press parts or prototype press parts. It could not be used for mass production.

(Means for Solving the Problems) The present invention solves the above-mentioned problems using extremely simple means. The surface of the mold body is covered with a hard synthetic resin layer on which the molding surface of the other mold is transferred in the shaft height state, and during the molding process, the hard synthetic resin layer is compressed by the thickness of the workpiece in the shirt height state. The feature is that the workpiece is pressurized.

(Example) In Figures 1 to 3, (lli die, (2) is punch, (31i blank holder is fully shown), punch (2) is fixed on machine base (4), and n1 bunch (2) is shown. Blank holder (31'k) on the outer periphery [Insert cushion bin (51'
It is supported vertically movably on the machine base (4) via the machine base (4), and the -10,000 die (11) is attached downward to the elevating frame (6) above the machine base (4).

The die (1) has a recess (7) facing the upper surface of the punch (2).
) and the die face part (8) facing the die holder (3)
A main body made of cast iron or other metal (1&) having
) fixed within the NFT hard synthetic resin layer (9). The material used to form the hard synthetic resin layer is, for example, urethane resin (abbreviated as KDF) that hardens at room temperature, which is the main component of ureol (registered trademark of Nippon Ciba Geigy Co., Ltd.) 6414A'. The subsequent sear D hardness (ISO868) is preferably about 65 to 70, the elongation to break is about 100 to 150%, the thickness is about 1 On, and when the blank with a thickness of t-O, a is pressed, it is 0. .6t
With a strain of ~1.2t, i.e. with a deformation of about 10%.
Other synthetic resins may be used as long as they can provide a compression pressure of 5-3-OK&/Im.

f! in the recess (7) of the die body (1a). l! To form the Iit composite resin layer (9), set the die body (1&) and punch (2) to the shaft height state as shown in Fig. 1, and connect the lower part of the recess (7) and the punch (2). As shown in Fig. 2, fill the gap αυ and inject the synthetic resin liquid from the injection hole αI while discharging the air through the air vent α2 and filling the synthetic resin liquid with light. is a hard plate with the punch shape transferred [@r coated with a resin layer (9)]
Ru.

During the pressing operation, the blank W is stretched with scissors n5 along the protruding part of the punch as shown in Figure 3 and Figure 5.
Next, as shown in Fig. 4, the molding surfaces of the die (1) and punch (2) contact the blank W all the time, and the hard urethane resin (91) is pressed by the thickness of the blank W in the state of the shaft height. The blank W is pressed against the punch (2) by applying force, and the punch shape and die shape are transferred to the blank W to perform a highly accurate forming process.

Next, the forming operation of the present invention will be further explained with reference to FIGS. 5 to 8.

Figure 5 shows m material 5PO (J Engineering S) used for automobile bodies.
) The steel material shown in the stress-strain diagram has a strain of approximately 0.2%.
When the yield point is reached and the strain exceeds about 0.2%, a very small increase in stress causes a significant increase in strain.

When applied to an actual press, Figure 6 (a)
), fix the blank w2 of length 11 with the die 111 and blank holder (3), and insert the punch (2) into the same figure (b).
) When the blank W is pushed up to the position shown in ), the blank W extends to It, even in the area where the distortion is small! When entering the plastic working area and reaching the state shown in the figure (0), it will be on a nearly horizontal line exceeding 0.2% in Figure 5, and parts with large curvature that require heavy working will also be hard synthetic. The pressing force P from the resin layer sufficiently molds the molded material, and in the state of the shaft height shown in FIG.

The stress-strain diagram of the hard synthetic resin having the above-mentioned properties is shown in the seventh figure.
n shown in the figure, the compressive stress is 1.5~ at 10% royal strain.
5kl? /m1i, which is 3 to 1 compared to general urethane.
Although it has a compressive stress of 0 times, epoxy resin and cast iron (FO
! Compared to 10), it is extremely easy to compress and deform. However, if the workpiece is the above-mentioned SPC and has a thickness of 0.8 mm, the thickness is about 10 mm.
The hard synthetic resin layer (9) is the hard synthetic resin shown in Figure 7.
It has been found that if the material has the characteristics of (1) and (2), it can be processed with high precision as the molding surface of the die.

Figure 8 shows a comparison of products obtained by pressing an automobile door skin using the die of the present invention and a cast iron die. 300° was measured from point 0 to the edge of the plate slightly below the recess Q. This part is difficult to form accurately due to the shadow of the recess Q. In the figure, a is a curve showing the change in the height of the punch, P shows a door skin molded with a die using the hard synthetic resin of the present invention, and 0 shows a door skin molded with a cast iron die. .

In the figure, it almost coincides with ffM b n ill 6, but on the other hand, the line O is the section A from point 0 to about 80 dragons and the section rlIB"t'U punch line a from 200 to 300B. There is a dent in the horizontal direction, and a sharp line and rise in the middle part.This is due to the large gap between the molds in this part, and the pressure applied in the narrow part of the gap of 7.9 m*. Wrinkles appear at the lever portions due to the elongation of the workpiece.Furthermore, even when viewed microscopically, surface irregularities due to uneven spacing are clearly visible.

The curve for this curve is extremely similar to curve a on the surface of the punch, and the smoothness of the surface is also the same as that of the punch surface, allowing for highly accurate forming. (Effects) Since the die forming surface is formed by transferring the shape of the punch to a hard resin layer that hardens at room temperature, there is no need for the difficult die-cutting, 99 hand-finishing, and 1-alignment operations required to make the die, making it extremely easy and You can make dies accurately. Since the blank is elastically suppressed by the resin layer on the die forming surface,
Smoothly molded and high precision products can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view showing the hard urethane resin layer forming process in the press mold device of the present invention, Fig. 2 is an enlarged view showing the sealing, and Figs. 3 and 4 are longitudinal cross-sectional views during and at the completion of the molding operation. Top view, Figure 5 is the stress-strain diagram of the blank, Figure 6 (a)
- (d) are explanatory diagrams of the molding operation, Figure 7 is a compressive stress-strain diagram of hard synthetic resin, and Figure 8 shows the shape of the product when used on the die of the present invention and a cast iron die. It is a line diagram. In the figure, tl...Die, (2...Punch, (3
)... Blank holder, (9)... Hard synthetic resin layer. W...Blank. 2 people Figure 1 Figure 2 Figure 4 Figure 7 Figure 6

Claims (1)

[Claims] In a press mold device equipped with a punch and a die, the surface of the mold body forming the base of one mold is coated with a hard synthetic resin layer on which the molding surface of the other mold is transferred in a shaft height state, and during the molding process, A press-type device characterized in that a hard synthetic resin layer is compressed by the thickness of the workpiece in a shaft height state to pressurize the workpiece.