JP2007237665A - Manufacturing method of resin molding - Google Patents

Abstract

The present invention provides a resin injection molding method in which a molded product can be easily taken out without being damaged.
A plurality of molds includes a mold opening step of injecting a resin into a cavity formed by mold closing of a plurality of molds, molding the resin, and then opening the molds. The first mold having the mold opening in the first direction and having the concave or convex portion 20b in the region facing the cavity, and the plurality of second molds each performing the mold opening in a direction different from the first direction. The mold opening step includes a first mold for releasing the first mold from the molded body in a state where a part of the concave portion or the convex portion 20b can be anchored to the molded body 4 of the resin. A method having a release sub-step and a second release sub-step for releasing the plurality of second molds 3 from the molded body 4 while maintaining the moorable state is used.
[Selection] Figure 2

Description

  The present invention relates to a method for producing a resin molded body having a concave portion or a convex portion, and particularly to a method for taking out a thermosetting resin molded body.

  In the production of a resin molded body having a concave portion or a convex portion, because of its shape, it is difficult to take out the molded body only by closing and opening a pair of molds, and a slide core is often used together. And the molded object formed by hardening the thermosetting resin etc. which were inject | poured in the cavity is generally taken out from a metal mold apparatus through the mold opening process of a metal mold | die shown in FIG. FIG. 4 is a schematic cross-sectional view showing the mold opening process of the resin molded body.

  For example, in the case of molding a molded body 94 having a cross-sectional shape in contact with a semicircular portion as shown in FIG. 4, molds 91 and 92 having convex portions 910b and 920b are used. The mold opening process for taking out 94 is as follows. First, when the molds 91 and 92 are opened, the molded body 94 is released from the fixed mold 91 having the convex portions 910b (FIG. 4A), and further the movable mold 92 having the convex portions 920b is molded. The mold is released from the body 94 (FIG. 4B). Next, a pair of slide cores 93 are slid in a direction perpendicular to the mold opening direction of the molds 91 and 92 via an angular pin (not shown) provided in the molds 91 and 92, and the molded body 94. Is released from the mold (FIG. 4C), and the molded body 94 is taken out.

In this way, as a simple method of taking out a molded body having a concave portion or a convex portion, a method of opening the pair of molds 91 and 92 as described above and moving the slide core 93 performed after the mold opening is performed. Is known, for example, from JP-A-60-38116. According to this method, when the molds 91 and 92 are released from the molded body 94, the molded body 94 is sandwiched between the slide cores 93, so that the molded body 94 can be released without swinging.
JP 60-38116 A

  However, when the molded body 94 is released from the slide core 93 in the mold opening process, the molded body 94 is separated while being supported only by the slide core 93. Therefore, the resin constituting the molded body 94 is one of the slides. When the core 93 is in close contact with the core 93, the molded body 94 is pulled in the moving direction of the slide core 93, and swings immediately after the mold release to come into contact with the slide core 93, the molds 91, 92, etc. and may be damaged. is there.

Thus, in order to prevent the molded body 94 from being deformed by the movement of the slide core 93, use of a release agent, processing of the slide core surface, and the like can be considered.
This invention is made | formed in view of the above subject, Comprising: It aims at providing the manufacturing method of the resin molding which can be taken out easily, without a molded object receiving damage.

In the present invention, the following means are used to solve the above problems.
After injecting resin into a cavity formed by mold closing of a plurality of molds and molding the resin, the mold has a mold opening step for opening the molds. A first mold having the mold opening in one direction and having a concave or convex portion in the region facing the cavity, and a plurality of second molds each opening the mold in a direction different from the first direction are included. The mold opening step includes a first release sub-step for releasing the first mold from the molded body in a state in which a part of the concave portion or the convex portion can be moored to the molded body of the resin, and the mooring A method having a second release sub-step for releasing the plurality of second molds from the molded body while maintaining a possible state is used.

  It is preferable that the mold opening direction of the plurality of second molds is a direction substantially orthogonal to the first direction. Each of the plurality of second molds is provided with a hole, and an angular pin that is inserted through the hole is provided. In the first release sub-step, the mold opening of the first mold is performed. The plurality of second molds are maintained in the closed state by the angular pins, and in the second mold release sub-step, the mold opening distance of the first mold is set to the first mold sub It is preferable that the plurality of second molds be moved by the angular pin by making the size larger than the step.

In addition, it is preferable to use a thermosetting resin for the resin.
Here, the “moorable state” means a state in which the concave portion or the convex portion of the first mold is moored to the molded body when the molded body is pulled in any mold opening direction of the second mold. Means.
Further, regarding “the mold opening direction of the second mold”, the two second molds may be opened in one direction (opposite direction), but may be opened in two directions. Further, three or more second molds may be opened in three or more directions. In this case, these multiple directions are all directions different from the first direction.

  When using the manufacturing method characterized by the mold opening step as in the present invention, in the first mold release sub-step, the first mold is released while the molded body is sandwiched between the plurality of second molds. The molded body does not swing. Further, when the plurality of second molds are released from the molded body, even if the constituent resin of the molded body is in close contact with the slide core and the molded body moves together with the second mold, Since a part is moored in the recessed area of the molded body, a part of the first mold serves to limit the movement of the second molded body. Therefore, even if the molded body swings due to the tensile force of the second mold, it is limited to a limited range, so that the molded body is not damaged.

Therefore, a good product state can be ensured without damage to the molded body when taken out. In particular, the present invention is preferable because it can be easily implemented without adding new functions and configurations to the molding apparatus or the like, and can provide a high-quality molded body without increasing the manufacturing cost.
In particular, when each of the mold opening directions of the second mold is substantially orthogonal to the first direction, the first mold has a great effect of suppressing the movement of the molded body based on the movement of the second mold. In particular, if the convex part of the first molding die that faces the concave part formed in the cavity protrudes in a direction orthogonal to the mold opening direction of the second molding die, This is desirable because the effect of suppressing movement can be increased.

  In addition, the structure of the mold apparatus using the angular pin allows the movement of the second mold to be stopped in the case of the mold opening of the first mold in the first mold release sub-step. In the case of mold opening of the first mold in the two mold release sub-step, it is preferable because the structure of the second mold can be released and the manufacturing method according to the present invention can be easily performed.

Hereinafter, embodiments according to the present invention will be described with reference to the drawings. In the present embodiment, as an example, a method of manufacturing a resin molded body in a mold apparatus using a thermosetting resin is used.
1. Overall process This manufacturing method includes a molding step of a thermosetting resin molding and a mold opening step for taking out the molding. In this manufacturing method, a mold apparatus (hereinafter simply referred to as “apparatus”) 10 shown in the schematic cross-sectional view of FIG. 1 is used. The vertical mold (Y direction) upper fixed mold 1 and the lower movable mold 2 perform mold closing or mold opening in the vertical direction, and between these molds 1 and 2, the fixed mold 1 The slide core 3 is moved in the horizontal direction (X direction) via the angular pin 5 provided in the above. In addition, as the angular pin 5, the thing including the rectilinear part 5a extended | stretched along a Y direction and the inclination part 5b inclined by the predetermined angle from the Y direction is used.
(1-1) Molding Process In the molding process, the mold of the apparatus 10 is first closed, and a space formed by the fixed mold 1, the movable mold 2, and the pair of slide cores 3 by the mold closing, so-called A cavity 6 is formed. Each of the fixed mold 1 and the movable mold 2 is provided with a fixed nest 1b and a movable nest 2b, which are hemispherical projections, and the opposing portion of the slide core 3 is predetermined from the nests 1b and 2b. It has a shape along the shape of the inserts 1b and 2b at a distance. Therefore, the space occupied by the cavity 6 in the present embodiment is formed in contact with the substantially bowl shape.

Then, a resin such as a thermosetting resin such as silicone resin is injected and filled into the cavity 6 so that the molds 1 and 2 have a predetermined temperature and are cured by heating to form a molded body 4 (for example, an optical lens). ). Here, the thermosetting resin is fed from an external injection cylinder (not shown) or the like, and is not melted for a certain period of time and is heated and melted to a temperature at which it can flow.
(1-2) Mold opening process Next, in the mold opening process, the molds 1 and 2 are opened to release the molds 1 and 2 from the molded body 4, and the slide core 3 is further molded. Release from 4. The release order will be described with reference to FIG. This figure is a schematic sectional view showing a mold opening process of the molded body 4.

The mold opening is started from the mold closed state. Specifically, first, the molded body 4 is released from the fixed mold 1 in the direction of the arrow (FIG. 2A). The mold release is performed by integrally moving the molded body 4, the movable mold 2, and the slide core 3, and the rectilinear portion of the angular pin 5 is placed in the oblique hole portion 3 b provided in the slide core 3. Only 5a is present.
Next, the movable mold 2 is released from the molded body 4 by a minute distance L1 in the mold opening direction of the molds 1 and 2 (arrow direction in FIG. 2A) (FIG. 2B). At the time of mold release, the molded body 4 and the slide core 3 are in an integrated state, and the movable mold 2 is moved relative to the molded body 4, so that the molded body 4 is released without swinging. Can be typed. At this time, the minute distance L1 is set to a distance at which the inclined portion 5b of the angular pin 5 does not enter the inclined hole 3b so that the distal end portion 20b of the movable insert 2b remains in the recessed region of the molded body 4. .

  Thereafter, as shown in FIG. 2C, the slide core 3 and the movable mold 4 are opened so that the inclined portion 5b of the angular pin 5 enters the inclined hole portion 3b. As a result, as shown in the drawing, the inclined portion 5b enters the inclined hole portion 3b, so that the slide core 3 slides in the horizontal direction. Therefore, the slide core 3 is released from the molded body 4 in the horizontal direction in a state in which the movable nest 2b and the molded body 4 can be moored with a separation distance of L2 (> L1).

Furthermore, the mold release distance of the slide core 3 with respect to the molded body 4 is increased by continuing the mold opening of the movable mold 2 (FIG. 2D). Thereby, it becomes possible to take out the molding 4 which is not supported from the slide core 3.
The details of releasing the slide core 3 from the molded body 4 will be described below.
2. Release of Slide Core The release of the slide core 3 from the molded body 4 will be specifically described with reference to FIG. FIG. 3 is a schematic cross-sectional view of an essential part of the molded body 4 and the slide core 3. In the present embodiment, the following steps are performed for releasing the slide core 3 from the molded body 4.

  First, as a first step, the movable nest 2b is released from the molded body 4 by a minute distance L1. In FIG. 3A, the slide core 3 released from the molded body 4 is shown, but when the movable insert 2b of the movable mold 2 is released from the molded body 4 by a minute distance L1 in the first step. The slide core 3 is not released from the molded body 4 (indicated by a dotted line in the figure). The minute distance L1 is a size that does not escape from the recessed area of the molded body 4.

  Next, as a second step, the slide core 3 is released from the molded body 4. The mold release of the slide core 3 in this step is to increase the mold opening distance of the movable mold 2, that is, the mold release distance between the movable insert 2b and the molded body 4 as shown in FIG. Do it by expanding to. As a result, the inclined portion 5b of the angular pin 5 enters the inclined hole 3b of the slide core 3, and the slide core 3 slides. However, from the first step to the end of the second step, the tip portion 20b of the movable nest 2b remains in the recessed region of the molded body 4 as shown in the drawing, that is, the molded body 4 is moved in the horizontal direction ( It is essential that the concave portion of the molded body 4 be moored to the movable insert 2b when moved in the X direction).

  With this slide, the pair of slide cores 3 are released from the molded body 4. At this time, if the movable nest 2b is completely removed from the concave portion of the molded body 4, the molded body 4 is supported only by the slide core 3 when the slide core 3 is released. Under the influence of the adhesive force with the body 4, the molded body 4 moves in a state where it is adhered to the slide core 3. In addition, when the molded body 4 is not completely cured, the molded body 4 is swung by a tensile force at the time of release, and is damaged due to contact with the convex portion of the slide core 3. Occurs. However, as in the present embodiment, when the slide core 3 is released from the mold, the tip 20b of the movable insert 2b remains in the recessed area of the molded body 4, so that the molded body 4 is temporarily attached to the slide core 3. Even if the molded body 4 is in close contact with the slide core 3 and receives a stress that moves in the X direction as the slide core 3 slides, the distal end 20b of the movable insert 2b is anchored in the recess and the molded body. Plays the role of stopping the movement of 4. Therefore, since the swing of the molded body 4 can be suppressed to a small level, there is no problem that the molded body 4 comes into contact with the slide core 3 and is damaged. Specifically, when the molded body 4 is swung when the slide core 3 is released from the molded body 4, when the tip 20b of the movable insert 2b does not remain in the recess (conventional form), Since the rocking is large, the surface of the molded body 4 (the part other than the inner surface of the concave portion) may come into contact with the slide core 3 or may further rock the molded body 4 until it contacts the molds 1, 2, etc. However, since the tip 20b remains in the recess of the molded body 4 as in the present embodiment, the molded body 4 is formed between the tip 20b of the movable nest 2b and the inner surface of the recess of the molded body 4. If rocking is performed by a separation distance secured at the time of mold release, the rocking is suppressed by the movable nest 2b. Thereby, the molded body 4 does not swing significantly. Of course, the molded body 4 is not deformed or destroyed.

  As for the remaining ratio of the distal end portion 20b of the movable insert 2b, a predetermined ratio is appropriately left in consideration of the molding material of the molded body 4, its thickness, the slide speed of the slide core 3, and the like. It is desirable. In the present invention, as long as even a part of the fixed insert 20b remains in the recessed area of the molded body 4 (S portion in FIG. 3B), it suppresses unnecessary movement and swinging of the molded body 4. Can be fulfilled. On the other hand, the release distance of the tip 20b is indispensable to be larger than 0, but the smaller the value, that is, the larger the amount the movable nest 2b occupies in the recessed area of the molded body 4 is desirable.

In the present embodiment, only the movable nest 2b remains in the recess of the molded body 4 and the method of restricting the movement of the molded body 4 along the sliding direction of the slide core 3 is employed. Even if it is set so that the fixed nest 1b of the fixed mold 1 remains in the concave region of the molded body 4 that faces the mold when releasing, the same or a larger effect of suppressing the movement and swinging of the molded body 4 can be obtained. Can be applied.
3. Others In the present embodiment, it is described that the molded body 4 having the concave portion is molded by the mold having the convex portion 20b. On the contrary, the molded body having the convex portion is formed using the mold having the concave portion. In the case of molding, the same effect can be obtained by releasing the slide core in a state where a part of the mold having the recess is moored to the projection of the molded body in the release step.

  Further, although a silicone resin is used as the thermosetting resin, other thermosetting resins may be used. In addition, regarding the shape of the molded body, the number of concave portions or convex portions may be one or more. In the above description, the number of the slide cores 3 is two, and the slide cores 3 move in directions opposite to each other by 180 degrees at the time of mold release, but may not necessarily be opposite to each other by 180 degrees. Further, the number of slide cores 3 may be three or more, and the slide cores 3 may move in different directions. In addition, as long as it is a mold apparatus that forms at least a cavity with a pair of molds and another pair of molds, the same effect can be obtained, and other shapes may be used. Of course, the number of molds and slide cores forming the cavity is not limited to the above-described contents, and may be larger. In addition, the operating direction of the mold and the slide core may not be the direction in which they intersect each other as long as it does not interfere with the removal of the molded body.

  Further, regarding the other configuration of the mold apparatus, in the present embodiment, the slide core is configured to slide via the angular pin, but a configuration using a hydraulic system or an air system may be used. In this embodiment, a metal mold is used as the mold, but the present invention is not limited to this, and other materials may be used.

  Since the molding method of the present invention can be used in a mold opening process for taking out molded bodies of various shapes, it is useful not only for thin film molding in the optical field but also in other fields. high.

It is a cross-sectional schematic diagram of the metal mold apparatus which concerns on this embodiment. It is a cross-sectional schematic diagram which concerns on the mold opening process for taking out the molded object of this embodiment. It is a principal part cross-sectional schematic diagram of the molded object which concerns on this embodiment. It is a cross-sectional schematic diagram which concerns on the mold opening process for taking out the molded object of the conventional form.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fixed mold 2 Movable mold 3 Slide core 4 Molding body of thermosetting resin 5 Angular pin 6 Cavity

Claims (4)

Injecting resin into a cavity formed by mold closing of a plurality of molding dies, and after molding the resin, a mold opening step of opening the plurality of molding dies,
In the plurality of molds, the mold is opened in a first direction, and a plurality of molds are opened in a direction different from the first direction, each having a concave or convex portion in a region facing the cavity. Of the second mold, and
The mold opening step includes
A first mold release sub-step for releasing the first mold from the molded body in a state in which a part of the concave portion or convex portion can be moored to the molded body of the resin;
A second molded sub-step for releasing the plurality of second molding dies from the molded body while maintaining the moorable state. A method for producing a resin molded body. 2. The method for producing a resin molded body according to claim 1, wherein a mold opening direction of the plurality of second molding dies is a direction substantially orthogonal to the first direction. A hole is provided in each of the plurality of second molding dies, and an angular pin that is inserted through the hole is provided.
In the first mold release sub-step, the first mold is opened and the plurality of second molds are maintained in the closed state by the angular pins.
In the second mold release sub-step, the plurality of second mold dies are moved by the angular pins by making the mold opening distance of the first mold larger than that of the first mold release sub-step. The manufacturing method of the resin molding of Claim 1 or 2 characterized by these. A thermosetting resin is used as the resin. The method for producing a resin molded body according to any one of claims 1 to 3.

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