JPS58211430A - Ultra-precision resin molding mold - 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 mold for resin molding, and particularly to a mold for resin molding suitable for molding ultra-precise resin molded products.

In recent years, in many manufacturing industries, the use of plastic parts for various food components has been considered for the purpose of reducing the weight and cost of products, and research is also being conducted into using plastic parts for precision equipment such as video cameras. Naturally, such precision equipment requires high precision for its parts, and therefore,
Various studies have been conducted on the molding of ultra-precision plastic parts, and currently improvements have been made to molding technology and control functions of molding machines, increasing the fidelity to the cavity, but it is still difficult to mold with an accuracy of 1 to 5 μm. The product has not yet been molded. This is because the cavity is deformed during molding due to mold clamping force, resin molding pressure, uneven temperature distribution, etc. Among these, the one that has the greatest influence is
This is the mold clamping force. Furthermore, although this mold clamping force is applied uniformly to the mold, it is generally applied unevenly to the mold because the die plates of the molding machine that perform mold clamping are not parallel. It is taking place. If the clamping force is applied unevenly to the mold, the cavity will be distorted, making it more difficult to improve the surface precision of the molded product.

That is, in the conventional mold, as shown in the side view of FIG. 1, the parallelism between the side plate 2 of the mold and the die plate 1 is poor, so that the mold clamping force 10 of the molding machine is applied unevenly to the mold. , the force 11 applied around the cavity 3 similarly acts non-uniformly,
The cavity becomes distorted.

As a conventional method for preventing mold deformation, as shown in FIG. 2, a hydraulic plunger 5 with purple 1. A type of molding machine was invented (1978-78263), but it was not suitable for large molds because the molding machine required a space for housing the mold that was larger than the thickness of the mold. In addition, in small molds, it is impossible to use all the hydraulic plungers, which has disadvantages such as unstable mold clamping and deformation of the mold due to support at several points.

The present inventors have solved these shortcomings of the conventional technology, and have developed a complete mold that eliminates cavity deformation and produces highly accurate molded products even in a molding machine with poor parallelism between the mold and the guide plate. As a result of intensive research, we found that when the elastic plate 8 is fully inserted between the mold 2 and the tie plate 1, the mold clamping force 10 applied unevenly to the mold is absorbed by the elastic plate 8, and the force 11 applied around the cavity 3 becomes uniform.
By forming the cavity 3, the cavity 3 is not distorted and the amount of deformation is extremely reduced.

That is, an object of the present invention is to provide a complete mold for ultra-precision resin molding that can mold plastic parts that require precision of 1 to 5 μm. Pressurized by pressure means (7) A mold for resin molding having a cavity for molding, a spool for guiding the molten resin into the cavity, and a surface of the mold facing the pressure means. An ultra-precision resin molding mold characterized by being provided with an elastic plate, and a cavity for pressurizing and molding molten resin using a total pressurizing means;
In a resin molding mold having a spool for guiding molten resin into a cavity, an elastic plate is provided on the surface of the mold facing the pressure means, and the peripheral edge of the cavity of the mold is made of cemented carbide. All the features of molding are made using ultra-precision resin molds, which can be easily achieved.

The invention will now be described in detail with reference to FIGS. 4 and 5, which fully illustrate the mode of implementation of the invention.

FIG. 4 is a partial sectional view showing the first embodiment of the present invention. In Fig. 4, the cavity part where the entire resin is molded]3
In a mold for resin molding consisting of a spool part 14 that guides the resin to a cavity part 13, an elastic plate is attached to the part facing and in contact with the die plate (not shown) (6) of the molding machine, which is the pressurizing means. elastic modulus is 1
A brass plate 15'f with a pressure of 0.06 x 1010 Pa was provided. In addition, in FIG. 4, 17 is a guide pin, and 18 is an ejector pin.

The parallelism between the mold warehouse and die plate is 120μ
When the mold was clamped by attaching it to a molding machine that was out of alignment by more than m, the amount of deformation of the capitai became 8 μm or less.

FIG. 5 is a partial sectional view showing a second embodiment of the present invention. In Fig. 4, the cavity part 1 to be molded with resin is shown.
3 and a spool part 14 area that guides the resin to the cavity part 13. In the resin molding mold, an elastic plate is provided with an elastic modulus as an elastic body plate in the part that faces and contacts the goo plate (not shown) of the molding machine, which is a pressurizing means. A mold was constructed using 15 brass plates having a diameter of 10.06 x 10'' Pa and 16 tungsten carbide plates having a total elastic modulus of 53.44 x 10'' Pa around the cavity portion 13. Note that 17.degree. 18 indicates the same thing as in FIG. Similar to the first embodiment, when this mold was tightened using a molding machine in which the parallelism between the die plates was out of alignment by 120 μm or more, the amount of deformation of the capitai became 5 μm or less. .

In the present invention, the elastic plate provided on the surface of the mold facing the pressure means is not particularly limited, and it is sufficient that the pressure chipping can be adjusted to the extent that the object of the present invention is achieved.
Preferably elastic modulus 1.5X10' to 1.5X101
A 1 Pa elastic plate is suitable, and specific examples include a brass plate or a bronze plate. When the pressure means faces both sides of the mold, it is most preferable to provide the elastic plate on both sides, but the effect of the present invention will not be exerted even if the elastic plate is provided on only one side. obtain.

In addition, the cemented carbide that forms the peripheral edge of the cavity has an elastic modulus of 2. I X 10'1~5.5 X 10
1ipa alloy is suitable, and specific examples include tungsten carbide and the like.

According to the present invention, the parallelism between the die plates is 120 μm.
Even in the above-mentioned crazy molding machines, does the elastic plate attached to the side of the mold act as a damper? This makes the stress distribution caused by the mold clamping force uniform in the vicinity of the cavity, preventing the cavity from being distorted, and further reducing the amount of deformation by surrounding the entire cavity with a hard material such as cemented carbide. Therefore, it has the effect of improving the precision of resin molded products. Therefore, even with a general molding machine that does not have precision finishing, it is possible to obtain high-precision parts whose precision is on the order of μm, which has the effect of molding high-precision parts at low cost.

[Brief explanation of the drawing]

Fig. 1 is a side view illustrating the relationship between the clamping force between a conventional mold and a Goui plate; the second cause is a side view showing a conventional method for preventing mold deformation; What is the relationship between mold clamping force and Gui plate? The side view to be explained, FIG. 4, is the first embodiment of the present invention.
The partial sectional view showing the embodiment, FIG. 5, is the second embodiment of the present invention. FIG. DESCRIPTION OF SYMBOLS 1... Gui plate, 2... Mold, 3... Cavity, 4... Gui plate, 5... Hydraulic plunger, 6... Lower mold, 7... Upper mold, 8... Elastic body plate, 9... Cemented carbide, (9) 10... Mold clamping force acting on the side surface of the mold from the Gui plate, 11... Mold clamping force acting within the mold, 13...capity part, 14...spool part, 15...brass plate,
16...Tungsten carbide, 17...Guide pin, 18...Eject pin. (10) Child 1111D Mine 2 Closed Mine 4 (2) Left figure

Claims (1)

[Scope of Claims] 1. A resin molding mold having a cavity for pressurizing and molding a molten resin by a pressure means, and a spool for guiding the molten resin into the cavity;
An ultra-precision resin molding mold characterized by an elastic plate on the surface facing the pressure means. 2. In the ultra-precision resin molding mold according to claim 1, the elastic plate has an elastic modulus of 1.5X10' to 1.5X10'.
A mold that is entirely characterized by being an elastic plate of 5 x 1 n11 pa. 3.% Allowance The ultra-precision resin molding mold according to claim 1 or 2, wherein the elastic plate is a brass plate. 4. The ultra-precision resin molding mold according to claim 1 or 2, wherein the elastic plate is a bronze plate. 5. A mold for resin molding having a cavity for pressurizing and molding the molten resin by means for pressurizing the entire molten resin, and a spool for guiding the molten resin into the entire cavity, in which:
A mold for ultra-precision resin molding, characterized in that an elastic plate is provided on the surface facing the pressure means, and the peripheral edge of the cavity of the mold is made of cemented carbide. 6. In the ultra-precision resin molding mold according to claim 5, the elastic plate has an elastic modulus of 1.5X10' to 1.5X10'.
7. A mold for ultra-precision resin molding according to item 5 or 6, in which the elastic plate has a diameter of 5 x 10" Pa. A mold for ultra-precision resin molding according to claim 5 or 6, characterized in that the elastic plate is a bronze plate. 9. Any one of claims 5 to 8, 9.
In the ultra-precision resin molding mold described in , the cemented carbide has an elastic modulus of 2. In the ultra-precision resin molding mold according to any one of claims 5 to 9 of the patent claim 10, which is an alloy of 1×10” to 5.5×10 Pa, A mold characterized in that the cemented carbide is tungsten carbide.