JPS5820343A - Die for press forming - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a press molding mold, and in particular, a press molding mold suitable for use in molding precision molded products having a relatively complicated shape and a large amount of plastic deformation. Regarding molds for use.

Generally, when a precision molded product with a relatively complex shape and a large amount of plastic deformation is molded using a press mold,
High-strength aluminum alloys may be used and warm temperatures may be used. However, the aluminum alloy has hot brittleness and its brittle temperature range is low, so the material temperature easily rises to the brittle temperature range due to the heat of deformation due to warm press forming and the heat of friction with the mold surface. Therefore,
Cracks and cracks often occurred on the surface of press-formed products.

In order to prevent the occurrence of such splits and flaws, in conventional press molding of kernel seeds, a mold release agent is applied to the mold surface of the press mold during molding.

However, this type of conventional press molding has the disadvantage that it is not possible to maintain precise molding for a long period of time due to the buildup of mold release agent residue on the mold surface of the press mold. be. In particular, this drawback becomes more obvious as the length of the molded product increases.

SUMMARY OF THE INVENTION An object of the present invention is to provide a press molding die that eliminates the drawbacks of the prior art and is capable of continuously molding precision molded products for a long period of time.

In the present invention, a vent is formed at the bottom of the mold surface to discharge the mold release agent.

The present invention will be described in detail below with reference to the drawings.

FIG. 1 and FIG. 2 show one embodiment of the present invention, and this press molding die includes a female die 1, a male die 2, and a middle die 3.
These combinations constitute a mold surface for molding a substantially cylindrical molded product 4 which is closed at one end and has a pillar extending from approximately the center of the closed surface. That is,
The female mold 1 presses the mold surface that forms the outer circumferential surface of the cylindrical wall of the molded product 40 onto the upper mold surface of the male mold 2Fi female mold 1, and presses the mold surface that forms the outer end surface of the closed surface of the molded product 4 into the middle mold 2. The molded product 40 has a mold surface which is installed inside the female mold 1 and forms the inner circumferential surface of the cylindrical wall, the inner end surface of the closing surface portion, and the pillar portion. A dowel bottle 5 is slidably fitted directly below the column forming part of the medium mold 3, and by sliding against the medium mold 3, the female mold 1 and the medium mold 3 are separated. The molded product 4 molded on the surface is extruded from within the mold surface and released from the mold.

As shown in detail in FIG. 2, the middle mold 3 has a groove 6.
is formed on the bottom of the mold surface and the contact surface with the female mold 1, and on the lower surface of the female mold 1, a second groove 7 is connected at one end to the first groove 6 and at the other end to the atmosphere. The grooves 6 and 7 substantially constitute a ventilation hole 8 that communicates the bottom of the mold surface space of the press mold with the atmosphere.

Next, the effects will be explained.

Here, using a conventional press molding die that does not have the ventilation holes 8, a mold release agent is applied to the mold surface, and the maximum cross-sectional processing rate is 90.
When a high-strength aluminum alloy was warm press-formed at a processing temperature of 450C, about 200 to 300 pieces were formed, and the molded product 4 was formed at part ■ in Fig. 1, that is, the molded product 4.
It should be explained that the dimensions were inaccurate at the bottom end of the press and the press work stress increased about 2.5 times.

When press forming was carried out using the press forming mold attached to the above-mentioned execution hook under the same conditions, the dimensions of the molded products were accurate even when the number of molded parts exceeded 10,000, and the stress of the press work changed. was not seen. ' This is because, in the case of this embodiment, the excess mold release agent applied to the mold surface is discharged from the vent hole 8 each time, and the residue of the mold release agent is often piled up during molding. This is because it is prevented. In this way, the mold release agent is discharged,
It was confirmed visually and by the mold release agent collected from the vent hole 8 that no lamination occurred.

In addition, in the above embodiment, the case where the ventilation hole is formed by the first and second groove parts is explained, but the ventilation hole is not limited to this. may be formed. The number of ventilation holes may be at least one. Further, the present invention is not limited to the case where high-strength aluminum is used, and can be applied to other press-forming molds of this type, and may be applied even when the middle mold is omitted.

As described above, according to the present invention, a ventilation hole is provided in the lower part of the surface of the mold to discharge excess mold release agent.

This makes it possible to continuously mold precision molded products.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view showing an embodiment of the present invention, and FIG. 2 is an enlarged partial cross-sectional view of Tabe shown in FIG.

Claims (1)

[Claims] 16 In a press molding die having a relatively complex shape and having a die surface for press forming with a large amount of plastic deformation, a terminal portion of the die surface in the pressing direction communicates with the outside of the die surface. A press molding die characterized in that at least one ventilation hole is formed.