JPH11320617A - Mold for molding and method for molding using the mold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mold for molding by which molding of fine parts can be highly precisely performed and a method for molding using the mold. SOLUTION: A fixed mold 110 and a passage 121 for passing a molding raw material when it is filled under pressure are provided and a movable mold 120 which can be tightly stuck and separated to a fixed mold 110 is provided. In addition, a transfer mold 114 which is transferrably arranged in the fixed mold 110 by the pushing pressure of the above described molding raw material filled under pressure and forms a space with approximately the same shape as the outer shape of the above described molded body between the fixed mold 110 and a movable mold 114 after transferring is provided. In addition, a projected mold 115 which is fixed on the fixed mold 110 and is arranged in a through- hole 114a provided in the transfer mold 114 and is stored in the above described through-hole before the transfer mold is transferred and is projected into the above described space after it is transferred, is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding die for producing a molded body made of a molding material to be filled under pressure and a molding method using the die.

[0002]

2. Description of the Related Art Generally, resin products are produced by an injection molding machine. With the injection molding method using this injection molding machine, the resin that is the molding material is melted and pressurized, injected and filled into the molding die, and then cooled and solidified, and the molded body is formed. This is a method of taking out a certain resin product from a molding die.

FIGS. 11A to 11E are a top view, an AA sectional side view, a bottom view, a top perspective view, and a bottom perspective view showing an example of a resin product. This resin product 1
It is used as a part of a small electronic component, is formed in a substantially rectangular parallelepiped shape, and is provided with a plurality of minute closed holes 2 extending from the upper surface to the bottom surface.

FIG. 12 is a sectional side view showing an example of a molding die used when the resin product 1 is manufactured by an injection molding machine. The molding die 10 includes a fixed core 11 which is a fixed die, and a movable core 12 which is a movable die which can move in a direction indicated by an arrow a with respect to the fixed core 11 and can be brought into close contact with and separated from the fixed core 11.

[0005] A cavity 13, which is a space in which the molten resin P is filled under pressure, is formed in the fixed core 11 in substantially the same shape as the outer shape of the resin product 1. A pin 14 for forming the hole 2 of the resin product 1 has a fixed core 11 at one end.
And the other end is disposed so as to protrude into the cavity 13. Further, the resin product 1 is placed in the cavity 13.
The eject pin 15 for projecting from the fixed core 1
1 is slidably disposed in a through hole 16 provided in the first through hole 1. The movable core 12 is provided with a gate 17 that is a passage for passing the molten resin P into the cavity 13 under pressure.

In the molding die 10 having such a configuration, since the shape of the pins 14 is a very thin columnar shape, when the molten resin P is charged into the cavity 13 under pressure, the molten resin P is exposed into the cavity 13 by the pressure. Shear stress concentrates on the root of the pin 14 which is being bent, and as shown in FIG. 12, the pin 14 may be bent, and the positional accuracy of the hole 2 of the resin product 1 may deteriorate or the hole 2 may be inclined. In the worst case, the pins 14 may be damaged. Further, even when the pin 14 is not deformed, there is a problem that the shear stress acts repeatedly at the root of the pin 14 and the life of the molding die 10 is shortened.

Therefore, as shown in FIG. 13, the shape of the root of the pin 24 exposed in the cavity 13 is formed into an R shape, and the shearing stress applied to the root of the pin 24 is dispersed, As shown in FIG.
The molding die 30 in which the shape of the pin 34 exposed inside is changed to a tapered shape to improve the strength of the pin 34 itself,
As shown in FIG. 15, a molding die in which the tip of the pin 44 is extended to be inserted into a hole 48 provided in the movable core 12 and the strength of the pin 44 is improved by holding the pin 44 at both ends. 40 are frequently used.

[0008]

The above-mentioned conventional FIG.
When the molding dies 20 to 40 shown in FIG. 15 are used, the deformation of the pins 24 to 44 can be avoided, but the shape of the hole of the resin product to be molded is the hole of the resin product 1 shown in FIG. 2 is different from the shape of FIG. That is, when the molding die 20 shown in FIG. 13 is used, the entrance of the hole of the resin product to be molded is formed into an R shape, and when the molding die 30 shown in FIG. The inner peripheral portion of the hole of the resin product to be formed is formed into a tapered shape, and a molding die 40 shown in FIG.
In the case where is used, the hole of the resin product to be molded is molded into the through hole. For this reason, there has been a problem that the design of the electronic component using the resin product must be changed, and when the design cannot be changed, the above-mentioned molding dies 20 to 40 cannot be applied.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a molding die capable of molding a fine portion with high accuracy and a molding method using the molding die. I do.

[0010]

SUMMARY OF THE INVENTION The object of the present invention is to provide a molding die for producing a molded article made of a molding material to be filled under pressure, comprising: a stationary mold; And a movable mold that can be brought into close contact with and detached from the fixed mold, and a pressing force of the molding material to be pressurized and filled. A movable mold that is movably disposed within the mold, forms a space having substantially the same shape as the outer shape of the molded body between the fixed mold and the movable mold after the movement, and is fixed to the fixed mold. And a protruding metal that is arranged in a through hole provided in the moving mold, is housed in the through hole before the moving mold moves, and protrudes into the space after the moving mold moves. And a mold.

In the present invention, the object is to fill a molding material into a molding die composed of a fixed die, a movable die, a movable die and a protruding die under pressure. A molding method for producing a molded body made of a molding material, wherein the movable mold is disposed so as to be movable in the fixed mold, and the projecting mold is fixed to the fixed mold and the movable mold is fixed to the movable mold. It is housed and arranged in the provided through-hole, the movable mold is brought into close contact with the fixed mold, the molding material is pressurized, passed through a passage provided in the movable mold, and is filled with pressure. While moving the movable mold by the pressing force of the molding material, the protruding mold is protruded from the through-hole, and is formed between the fixed mold, the movable mold, the movable mold, and the protruding mold. Filling the molding material in the space to be formed to form a molded body made of the molding material More is achieved.

According to the above configuration, the projecting mold initially stored and protected in the movable mold operates so as to gradually protrude as the molding material is filled, so that the filling pressure is reduced. It is possible to form the minute part with high precision by preventing deformation of the protruding die and the like, without being hindered.

[0013]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Note that the embodiments described below are preferred specific examples of the present invention, and therefore, various technically preferable limitations are added. However, the scope of the present invention is not limited to the following description in the following description. It is not limited to these forms unless otherwise stated.

FIG. 1 is a sectional side view showing an embodiment of a molding die according to the present invention. The molding die 100 is a fixed core 110 which is a fixed die, and a movable die which is movable with respect to the fixed core 110 in a direction indicated by an arrow a (hereinafter, referred to as an axial direction) to be able to come into close contact with and detach from the fixed core 110. And a core 120.

The fixed core 110 includes first, second, and third core bodies 111, 112, and 113 that are laminated in three layers in the axial direction.
And a movable mold that is disposed so as to be slidable in the axial direction within the first core body 111 and is filled with a molten resin under pressure to form a cavity that is a space having substantially the same shape as the outer shape of the resin product. It is roughly constituted by a movable core 114 and a core pin 115 which is disposed so as to protrude into the cavity and is a protruding die for forming a hole in a resin product.

The first core body 111 includes a moving core 114.
A through hole 111b having a step 111a into which is inserted is provided in the axial direction. The ball plunger 116 is embedded in the inner wall of the through hole 111b in a direction perpendicular to the axial direction. The second core body 112 has three through holes 112a, 112b, 112c and a closed hole 11
2d is provided in the axial direction. Then, the through hole 112
a, a guide bush 117 is fitted into the through hole 1.
One end of a core pin 115 is fixed to 12b, and an ejector pin 118 for projecting a resin product from a cavity is inserted into a through hole 112c.
One end of a spring 119 is locked to d.

The third core body 113 has two through holes 1
13a and 113b are provided in the axial direction. And
One end of the guide bush 117 is fitted into the through hole 113a, and the ejector pin 11 is inserted into the through hole 113b.
8 has been inserted. The moving core 114 has one through-hole 114 a coaxially with the through-hole 112 b of the second core body 112, and further has a guide pin 114 b on the end face on the second core body 112 side.
7 so that it can be inserted into
14 c is provided coaxially with the closed hole 112 d of the second core body 112.

Further, on the peripheral surface of the moving core 114, the first
A step 114d that engages with the step 111a of the through hole 111b of the core body 111 is provided. And the through hole 1
The core pin 115 is inserted into the closed hole 11a.
The other end of the spring 119 is locked to 4c. The movable core 120 is provided with a gate 121 which is a passage for passing the molten resin into the cavity under pressure.

A molding method using the molding die 100 having such a configuration will be described with reference to FIGS.
In the initial state, as shown in FIG.
0 is away from the fixed core 110 and
Is pressed by the restoring force of the spring 119 and the step 1
14d is abutted on the step 111a of the first core body 111.

At this time, the movable core 12 of the movable core 114
The end face on the 0 side is slightly recessed from the end face on the movable core 120 side of the first core body 111, and the tip face of the core pin 115 is substantially flush with the end face on the movable core 120 side of the movable core 114. In this state, the peripheral surface of the core pin 115 is protected by the movable core 114. Further, the ball plunger 116 is disengaged from the movable core 114, and the tip surface of the ejector pin 118 is substantially flush with the end surface of the second core body 112 on the first core body 111 side.

First, as shown in FIG.
Moves in the axial direction, and the end face of the movable core 120 comes into close contact with the end face of the fixed core 110. Next, as shown in FIG. 4, the molten resin P is pressed to pass through the gate 121, the spring 119 is elastically deformed by the pressing force of the molten resin P charged and filled, and the movable core is guided by the guide pin 114b. 114 is moved in the axial direction in the through hole 111b of the first core body 111.

Then, the molten resin P is filled into a space formed by the end face of the movable core 120, the peripheral face of the through hole 111b of the first core body 111, and the end face of the movable core 114, that is, into the cavity. With the movement of the moving core 114, the core pin 115 protrudes from the through hole 114a into the cavity. Then, as shown in FIG.
The filling of the molten resin P is stopped at the stage where the end face of No. 4 hits the end face of the second core body 112. At this time, the ball plunger 116 fits into a concave portion provided on the peripheral surface of the moving core 114, and holds the position of the moving core 114.

At this time, the shape of the cavity is substantially the same as that of the resin product, and the shape of the portion of the core pin 115 protruding from the through hole 114a is substantially the same as the hole of the resin product. . Therefore, by cooling the molding die 100 in this state, the molten resin P can be solidified to form the resin product PP.

After cooling the molding die 100, as shown in FIG. 6, the movable core 120 is separated from the fixed core 110, and the sprue S solidified in the gate 121 of the movable core 120 is taken out and discarded. Then, as shown in FIG. 7, the ejector pins 118 protrude from the end surface of the second core body 112 to press the moving core 114, and the ball plunger 116 is moved from the concave portion provided on the peripheral surface of the moving core 114. remove.

Subsequently, the movable core 114 is further pressed by the restoring force of the spring 119 and the pressing force of the ejector pin 118, and is guided by the guide pin 114b.
The moving core 114 is inserted into the through hole 111b of the first core body 111.
The moving core 114 is moved in the axial direction until the step 114d of the moving core 114 comes into contact with the step 111a of the through hole 111b.
At this time, the resin product PP is the movable core 1 of the movable core 114.
20 and pushed out from the end face of the first core body 111 on the movable core 120 side, and the core pin 1
15 is extracted from the hole H of the resin product PP, and the resin product PP is finally discharged from the molding die 100.

As described above, the core pin 115, which is initially housed and protected in the movable core 114, operates so as to gradually project from the movable core 114 into the cavity as the molten resin P is charged. The filling pressure is not directly applied to the core pin 115, and the deformation or the like of the core pin 115 is prevented, so that the hole H of the fine resin product PP can be formed with high precision.

FIG. 8 is a sectional side view showing a second embodiment of the molding die of the present invention. The same components as those of the molding die shown in FIG. I do. The molding die 200 has basically the same configuration as the molding die 100 shown in FIG.
The configuration is different in that a hydraulic mechanism 201 and a hydraulic controller 202 are provided instead of the ejector pin 118 and the spring 119. According to the molding die 200 having such a configuration, the filling of the molten resin P and the resin product P
Since the operation such as the removal of P can be finely controlled, high-precision injection molding can be performed regardless of the type of the molten resin P and the shape of the resin product PP.

FIG. 9 is a sectional side view showing a third embodiment of the molding die of the present invention. The same components as those of the molding die shown in FIG. I do. The molding die 300 has basically the same configuration as the molding die 200 shown in FIG. 8, but differs in that a moving core 314 is provided for forming a hole in a resin product. Has become. According to the molding die 300 having such a configuration, it can be used when the resin product has multiple holes.

FIG. 10 is a sectional side view showing a fourth embodiment of the molding die of the present invention. The same components as those of the molding die shown in FIG. I do. This molding die 400 has basically the same configuration as the molding die 300 shown in FIG. 9, but differs in that a moving core 414 is provided for forming an oblique hole in a resin product. It has a configuration. Molding mold 40 having such a configuration
According to 0, it can be used when the resin product is multi-stage and has inclined holes. In each of the embodiments described above, the side on which the moving core and the like are provided is configured as a fixed mold, but the same effect can be obtained by configuring the side on which the moving core and the like are provided as a movable mold. be able to.

[0030]

As described above, according to the present invention, it is possible to form a fine portion with high precision, so that, for example, the yield of electronic components can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional side view showing an embodiment of a molding die of the present invention.

FIG. 2 is a first cross-sectional side view for explaining a molding method using the molding die of FIG. 1;

FIG. 3 is a second sectional side view for explaining a molding method using the molding die of FIG. 1;

FIG. 4 is a third cross-sectional side view for explaining a molding method using the molding die of FIG. 1;

FIG. 5 is a fourth sectional side view for explaining a molding method using the molding die of FIG. 1;

FIG. 6 is a fifth sectional side view for explaining a molding method using the molding die of FIG. 1;

FIG. 7 is a sixth sectional side view for explaining a molding method using the molding die of FIG. 1;

FIG. 8 is a sectional side view showing a second embodiment of the molding die of the present invention.

FIG. 9 is a sectional side view showing a third embodiment of the molding die of the present invention.

FIG. 10 is a sectional side view showing a fourth embodiment of the molding die of the present invention.

FIG. 11 is a top view showing an example of a general resin product,
A sectional view taken along the line A, a bottom view, a top perspective view, and a bottom perspective view.

FIG. 12 is a sectional side view showing an example of a conventional molding die.

FIG. 13 is a sectional side view showing a second example of a conventional molding die.

FIG. 14 is a sectional side view showing a third example of a conventional molding die.

FIG. 15 is a sectional side view showing a fourth example of a conventional molding die.

[Explanation of symbols]

100: Mold for molding, 110: Fixed core, 11
DESCRIPTION OF SYMBOLS 1 ... 1st core body, 112 ... 2nd core body, 1
13: Third core body, 114: Moving core, 11
5: core pin, 116: ball plunger, 1
17: guide bush, 118: ejector pin, 119: spring, 120: movable core,
121 ・ ・ ・ Gate

Claims (4)

[Claims] 1. A molding die for producing a molded body made of a molding material to be pressure-filled, comprising: a stationary mold; and a passage for passing the molding material under pressure. A movable mold that can be brought into close contact with and detached from the fixed mold; and a movable mold disposed in the fixed mold by a pressing force of the molding material to be filled under pressure. And a movable mold that forms a space having substantially the same shape as the outer shape of the molded body between the movable mold and the movable mold, and a movable mold fixed to the fixed mold and in a through hole provided in the movable mold. And a projecting die that is disposed in the through-hole before the moving die moves, and protrudes into the space after the moving die moves. 2. The molding die according to claim 1, wherein the movable die is urged by an elastic member. 3. The molding die according to claim 1, wherein said movable die is urged by pressure generating means. 4. A molding method in which a molding material is pressure-filled into a molding die composed of a fixed die, a movable die, a movable die, and a protruding die to form a molded body made of the molding material. Wherein the movable mold is disposed so as to be movable in the fixed mold, and the protruding mold is fixed to the fixed mold and housed and arranged in a through hole provided in the movable mold. The movable mold is brought into close contact with a fixed mold, and the molding material is pressurized and passed through a passage provided in the movable mold. While moving the mold, the projecting mold is made to protrude from the through hole, and the molding material is filled in a space formed between the fixed mold, the movable mold, the movable mold, and the projecting mold. And forming a molded body made of the molding material.