JP3075300B2 - Mold device for two-color molding of cover in cassette tape storage case and two-color molding method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-color molding apparatus and a two-color molding method for a cover in a cassette tape storage case.

[0002]

2. Description of the Related Art A cassette tape storage case is constructed by pivoting a cover on a base. This cover has a pocket portion into which the side portion on the head corresponding portion side or the opposite side portion is inserted when the cassette tape is stored. When the cover is injection-molded with a resin, the pocket portion has an undercut shape in the opening and closing direction of the fixed mold member and the movable mold member, so that the pocket portion is formed by the slide core. . Conventionally,
The cover is entirely formed of one kind of transparent resin. However, recently, there is a demand for two-color molding of the cover in order to improve the appearance and the commercial value. For example, it is demanded that only a portion of a cover facing a label or the like of a stored cassette tape be made transparent and other portions be made opaque. However,
As described above, since the cover has a pocket portion and a slide core must be used for forming the pocket portion, it is not easy to form the cover in two colors.

[0003]

As described above, as described above,
In the cassette tape storage case, the entire cover is formed of one kind of transparent resin, but it is desired to form the cover in two colors. However, since the cover has a pocket portion and a slide core must be used for molding the pocket portion, a two-color molding of the cover requires a device such as a metal mold. Therefore, an object of the present invention is to enable two-color molding of a cover by devising a mold configuration and an operation method thereof.

[0004]

According to the present invention, there is provided a method for two-color molding of a cover in a cassette tape storage case according to the first aspect of the present invention. A pocket portion is formed between a second surface portion bent from the edge of the second surface portion and a third surface portion bent from the edge of the second surface portion and opposed to the first surface portion. A first mold member forming an outer surface of the first surface portion on the side opposite to the pocket portion, and forming the first surface portion and the first surface member with respect to the first mold member. A second mold member intersecting the three surface portions and movable in a direction parallel to the second surface portion and forming outer surfaces of the second surface portion and the third surface portion; and a second mold member with respect to the second mold member. The pocket is movable in a direction parallel to the first surface portion and the third surface portion. A third mold member forming the inner surface of the portion and the first surface portion, and a fourth mold member penetrating the third mold member so as to be movable in a direction intersecting the moving direction thereof and forming the inner surface of the first surface portion. The mold member is clamped by using a two-color molding mold apparatus having the mold member of the first embodiment, and the cavity wall of the fourth mold member is brought into contact with the cavity wall of the first mold member. Thereby, a first cavity is formed between the mold members, the first cavity is filled with a first resin, and after the first resin is solidified, the fourth mold member is removed. The first mold member, the fourth mold member, and the first resin filled in the first cavity are moved by moving the cavity wall until the cavity wall comes to a position that becomes the inner surface of the first surface portion of the cover. A second cavity is formed between the two, and the second cavity is filled with a second resin. Then, after the second resin is solidified, the fourth mold member is moved out of the movement locus of the third mold member, and then the first mold member and the second mold member are moved. The mold is opened, and the third mold member is moved out of the movement locus of the molded pocket portion of the cover when the mold is released to release the cover.

[0005] A two-color molding die apparatus for a cover in a cassette tape storage case according to a second aspect of the present invention is the first type.
A surface portion, a second surface portion bent from an edge of the first surface portion, and a third portion bent from an edge of the second surface portion and opposed to the first surface portion.
A two-color molding die apparatus for a cover having a pocket portion formed between the first surface portion and the cover and pivotally attached to the base to form a cassette tape storage case. 1 mold member, and outer surfaces of the second surface portion and the third surface portion which are movable with respect to the first mold member in a direction intersecting with the first surface portion and the third surface portion and in parallel with the second surface portion. And a second mold member that moves in a direction parallel to the first surface portion and the third surface portion with respect to the second mold member to form inner surfaces of the pocket portion and the first surface portion. A third mold member, and an inner surface of the first surface portion which is movably penetrated by the third mold member in a direction intersecting the moving direction thereof and which is movable outside the movement locus of the third mold member. Moveable to a fourth mold member forming the second mold member Its cavity walls the fourth die member provided is that a stopper for stopping the position in which the inner surface of the first face of the cover.

[0006]

In the two-color molding device and the two-color molding method for the cover in the cassette tape storage case according to the present invention, the third surface for forming the pocket portion of the cover has the first molding member and the second molding member. In the same manner as in the related art, the third mold member can move in the direction parallel to the first surface portion and the third surface portion with respect to the second mold member. Forms an inner surface of the pocket portion. Despite having such a third mold member, the third mold member is movable in a direction intersecting the moving direction so that a different color portion can be formed on the first surface portion of the cover. A penetrated fourth mold member is provided. That is, the first cavity is formed between the mold members by bringing the cavity wall of the fourth mold member into contact with the cavity wall of the first mold member, and the first cavity is formed in the first cavity. And then moving the fourth mold member until the cavity wall comes to a position where the cavity wall becomes the inner surface of the first surface portion of the cover, whereby the first mold member and the fourth mold member are moved. A second cavity is formed between the first cavity and the first resin filled in the first cavity, and the second cavity is filled with the second resin to perform two-color molding. As it is, the third mold member cannot move because it is obstructed by the fourth mold member,
At the time of mold release, the fourth mold member is further moved and extracted from the third mold member, so that the third mold member can be extracted from the pocket portion.

In the two-color molding die apparatus for the cover of the cassette tape storage case according to the second aspect of the present invention,
When filling the cavity with the second resin, the fourth mold member is stopped by the stopper at a position where the cavity wall becomes the inner surface of the first surface portion of the cover, and when the mold is released, the stopper is moved. By moving the fourth mold member, the third
From the mold member.

[0008]

An embodiment of the present invention will be described below with reference to the drawings. First, the configuration of the cassette tape storage case will be described with reference to FIG. In FIG. 1, reference numeral 1 denotes a cassette tape, and the cassette tape 1 has a head corresponding portion 2 on one side along the longitudinal direction. Also,
Reference numeral 6 denotes a cassette tape storage case.
Is composed of a base 7 and a cover 9 pivotally connected to the base 7 via a hinge portion 8. In addition,
The direction of the rotation axis of the base 7 and the cover 9 coincides with the longitudinal direction of the base 7 and the cover 9. The cover 9 includes a rectangular flat plate-shaped first surface portion 11, a slender rectangular flat plate-shaped second surface portion 12 that is bent vertically from one edge along the longitudinal direction of the first surface portion 11, and a longitudinal surface of the second surface portion 12. A third surface 13 in the form of an elongated rectangular flat plate bent perpendicularly from one edge along the direction and opposed to the first surface 11, and along the short direction of the first surface 11, the second surface 12 and the third surface 13. It comprises a pair of fourth surface portions 14 that connect the edges together. Thus, between the first surface portion 11, the second surface portion 12, the third surface portion 13, and the fourth surface portion 14, the pocket portion into which the side portion on the head corresponding portion 2 side or the opposite side portion of the cassette tape 1 is inserted. 15 are formed. And the cover 9 is
It is a color molded product. That is, a transparent window portion 16 is partially formed in the first surface portion 11, and
The portion other than the window 16 is opaque.

Next, the configuration of a mold for forming the cover 9 in two colors will be described with reference to FIGS. The mold 21 includes a fixed mold member (first mold member) 22 that forms an outer surface of the first surface portion 11 of the cover 9 on the side opposite to the pocket portion 15.
A movable mold member (second mold member) 23 forming the outer surfaces of the second surface portion 12, the third surface portion 13, and the fourth surface portion 14, and the window portion 16 in the pocket portion 15 and the first surface portion 11 A first slide core (third mold member) 24 forming the inner surface of
A second slide core (a fourth mold member) 25 forming the inner surface of the window portion 16 and a further slide core (not shown) for forming the hinge portion 8 in the fourth surface portion 14; It has. The fixed mold member 22 and the movable mold member 23 are relatively perpendicular to the illustrated vertical direction, that is, orthogonal to the first surface portion 11 and the third surface portion 13 and to the second surface portion 12 and the fourth surface portion 14. It moves in a parallel direction and opens and closes. Further, the first slide core 24 is attached to the movable mold member 23 in the horizontal direction in the drawing, that is, the first surface portion 11 and the third surface portion.
It is supported movably in a direction parallel to 13 and orthogonal to the second surface portion 12 and the fourth surface portion 14. The first slide core 24 has an inclined hole 27 into which an angular pin 26 fixed to the fixed mold member 22 is slidably inserted. These angular pins 26 and inclined holes
27 is inclined rightward downward in the drawing, whereby the first slide core 24 moves rightward when the fixed mold member 22 and the movable mold member 23 open the mold, It moves in the opposite direction when closing the mold. Further, the second slide core 25 is slidably fitted in a slide core storage space 28 formed in the movable-side mold member 23 in the vertical direction in the figure, and is fitted to the first slide core 24. It penetrates through holes 29 formed and overlapping the storage space 28 during mold clamping. The second slide core 25 has a leg 30 projecting downward. Further, the fixed-side mold member
A stopper storage space 31 is formed in the storage space 22 so as to be continuous below the slide core storage space 28, and a stopper 32 is fitted into the storage space 31 so as to be slidable in the left-right direction in the figure. This stopper 32 is a leg that protrudes upward.
33. When the stopper 32 moves to the left in the figure, the leg 30 of the second slide core 25 and the leg 33 of the stopper 32 face each other. When the stopper 32 moves to the right in the figure, both legs The parts 30, 33 are located off. At the same time, the height of the second slide core 25 including the leg 30 in the illustrated vertical direction is from the upper wall of the cavity of the fixed mold member 22 to the upper surface of the leg 33 of the stopper 32 at the time of mold clamping. It is smaller than the distance by the thickness of the window 16 of the cover 9. Further, a fluid pressure (hydraulic or pneumatic) cylinder device 34 for driving the second slide core 25 is assembled to the movable mold member 23. The moving piston rod 35 is connected to the second slide core 25 through a through hole 36 formed in the stopper 32. Further, a hydraulic cylinder device 37 for driving the stopper 32 is also attached to the movable mold member 23. Are linked. Thus, with the above configuration, the fixed mold member 22, the movable mold member 23, and the first slide core 24 are clamped, and the cavity wall 25a on the upper surface of the second slide core 25 is fixed to the fixed mold member. When the fixed mold member 22 and the movable mold member 22 are in contact with the upper wall of the cavity of the member 22,
23, a first slide core 24 and a second slide core 25
A first cavity 41 having the shape of the cover 9 excluding the window portion 16 is formed therebetween, and is filled with a first resin described later.
Then, when only the second slide core 25 is lowered in the mold-clamped state until its leg 30 abuts against the leg 33 of the stopper 32, the fixed mold member 22, the second slide core 25 and the The first filled in the first cavity 41
Second cavity in the shape of window 16 between
42 is formed and filled with a second resin described later. Further, the fixed side mold member 22 is provided with a first gate 43 opening to the first cavity 41 and a second gate 44 opening to the second cavity 42. , 44 are provided with bushings 47, 48 having valves 45, 46 built therein. Although not shown, the inside of one bush 47 communicates with a nozzle of an injection molding machine that injects an opaque first resin, and the other bush 47
The inside of 48 communicates with the nozzle of the injection molding machine that injects the transparent second resin. Although not shown, a projecting pin is provided on the movable mold member 23 side to project and release the cover 9 as a molded product when the mold is opened.

Next, a two-color molding method using the mold 21 will be described. First, as shown in FIG. 1, the fixed-side mold member 22, the movable-side mold member 23, and the first slide core 24 are clamped, and the second slide core 25 is illustrated by a fluid pressure cylinder device. By pressing upward, the cavity wall 25a of the second slide core 25 is fixed to the fixed mold member 22.
Abut the top wall of the cavity. In this state, the fixed mold member 22, the movable mold member 23, the first slide core 24
A first cavity 41 is formed between the second slide core 25 and the second slide core 25. Then, the first resin is poured into the first cavity 41 from the first gate 43 and filled therein. Next, after the first resin in the first cavity 41 is solidified,
As shown in FIG. 2, the second slide core 25 is lowered by driving the hydraulic cylinder device 34 with the stopper 32 positioned to the left in the drawing. This second slide core 25
Is stopped when the leg 30 abuts against the leg 33 of the stopper 32. In this state, the cavity wall 25a of the second slide core 25 becomes the inner surface of the window 16 of the first surface 11 of the cover 9. And the fixed mold member 22, the second slide core
A second cavity 42 is formed between the first resin 25 filled and solidified in the first cavity 41. Then, the second resin is poured into the second cavity 42 from the second gate 44 and filled therein. At this time, a strong resin pressure is applied to the second slide core 25, but since the second slide core 25 is supported by the stopper 32, the second slide core 25 can reliably withstand the resin pressure, and the second slide core 25 twenty five
Does not shift. Then, the second cavity 41
After the second resin inside is solidified, the stopper 32 is moved rightward in the figure by driving the fluid pressure cylinder device 37 as shown in FIG. After being removed from the section 30, as shown in FIG. 4, the second slide core 25 is lowered by driving the hydraulic cylinder device 34, and is removed from the through hole 29 of the first slide core 24.
That is, the second slide core 25 is located outside the movement locus of the first slide core 24. Next, as shown in FIG. 5, the fixed mold member 22 and the movable mold member 23 are opened. Accordingly, the first slide core 24 moves rightward in the figure without being hindered by the second slide core 25 and is removed from the pocket portion 15 of the formed cover 9. At the same time, the cover 9 is protruded by the protruding pin and is released. At this time, the first slide core 24
Has already moved out of the movement locus of the pocket portion 15 of the cover 9 at the time of release, and does not hinder release.

As described above, according to the embodiment, since the third surface portion 13 of the cover 9 has an undercut shape with respect to the opening and closing direction of the fixed mold member 22 and the movable mold member 23, the first surface portion is formed. The slide core 24 is provided, but the second slide core 25 penetrating the first slide core 24 is provided, so that the first surface portion 11 of the cover 9 has a different color from other portions of the cover 9. The transparent window portion 16 can be formed. Then, by forming the cover 9 in two colors in this manner, the appearance of the cover 9 is improved, and the commercial value thereof can be increased. By the way, the second slide core 25
The above three positions must be taken: the position when forming the first cavity 41, the position when forming the second cavity 42, and the position when releasing the mold. A strong resin pressure is applied to the second slide core 25 at the intermediate position where the second cavity 42 is formed. However, in the above embodiment, the stopper 32 that moves in the direction orthogonal to the direction in which the second slide core 25 moves,
Since the second slide core 25 is held at the position where the second cavity 42 is formed, it is possible to reliably withstand the resin pressure even though this position is an intermediate position of the movement of the second slide core 25. Can be. Further, since the second slide core 25 is configured to move out of the movement locus of the first slide core 24, the first slide core 24 can be moved irrespective of the second slide core 25. The space to be provided near the cavities 41 and 42 to allow the movement of the mold member can be reduced.

Note that the present invention is not limited to the above-described embodiment, and various modifications can be made. For example,
The cassette tape storage case 6 of the above-described embodiment is
Although the rotation axis direction of the cover 7 and the cover 9 coincides with the longitudinal direction of the base 7 and the cover 9, they may coincide with the short direction. In this case, a pocket is formed at the longitudinal end of the cover, and the longitudinal end of the cassette tape is inserted into this pocket.

[0013]

According to the present invention, when forming a cover having a pocket portion, the cover portion is formed by forming the pocket portion.
Despite providing a third mold member that moves in a direction intersecting the opening and closing direction of the first mold member and the second mold member, a fourth member penetrating through the third mold member is provided. Is provided, and the fourth mold member is moved in two stages,
The first resin and the second resin are sequentially filled, and at the time of releasing the cover, which is a molded product, the fourth mold member is connected to the third resin.
By not hindering the movement of the mold member, the cover having the pocket portion can be formed in two colors, and the appearance of the cover can be improved and its commercial value can be increased. become. Further, since the fourth mold member is moved out of the movement locus of the third mold member, the third mold member can be moved irrespective of the fourth mold member. The space to be provided near the cavity for allowing the movement of the mold member can be reduced, and the strength of the mold near the cavity can be increased.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a two-color molding die apparatus according to an embodiment of the present invention when a first cavity is formed.

FIG. 2 is a cross-sectional view when a second cavity is formed.

FIG. 3 is a cross-sectional view showing a state where a stopper is removed from the second slide core.

FIG. 4 is a sectional view showing a state where a second slide core is removed from the first slide core;

FIG. 5 is a cross-sectional view when the mold is opened and a molded product is released from the mold.

FIG. 6 is a perspective view of the cassette tape storage case.

[Explanation of symbols]

 6 Cassette Tape Storage Case 7 Base 9 Cover 11 First Surface 12 Second Surface 13 Third Surface 15 Pocket 21 Mold 22 Fixed Mold Member (First Mold Member) 23 Movable Mold Member (Second Mold Member) Mold member) 24 First slide core (third mold member) 25 Second slide core (fourth mold member) 32 Stopper 41 First cavity 42 Second cavity

Claims (2)

(57) [Claims] A first surface portion, a second surface portion bent from an edge of the first surface portion, and the first surface portion bent from an edge of the second surface portion.
A two-color molding die apparatus for a cover, wherein a pocket portion is formed between a third surface portion facing the surface portion and is pivotally attached to the base to constitute a cassette tape storage case.
A first mold member forming an outer surface on the side opposite to the pocket portion of the surface portion, and moving in a direction intersecting the first surface portion and the third surface portion and parallel to the second surface portion with respect to the first mold member; A second mold member capable of forming outer surfaces of the second surface portion and the third surface portion; and a second mold member movable in a direction parallel to the first surface portion and the third surface portion with respect to the second mold member. A third mold member forming an inner surface of the pocket portion and the first surface portion, and a third mold member penetrating the third mold member movably in a direction intersecting the moving direction thereof to form an inner surface of the first surface portion. The mold member is clamped using a two-color molding mold device having the fourth mold member and the cavity wall of the fourth mold member is brought into contact with the cavity wall of the first mold member. By contacting, a first cavity is formed between the mold members,
The first cavity is filled with a first resin, and the first resin is filled in the first cavity.
After the resin is solidified, the first mold member and the fourth mold member are moved by moving the fourth mold member until the cavity wall comes to a position where the cavity wall becomes the inner surface of the first surface portion of the cover. And a first resin filled in the first cavity, a second cavity is formed, the second cavity is filled with a second resin, and after the second resin is solidified, The fourth mold member is moved out of the movement locus of the third mold member, and then the first mold member and the second mold member are opened, and the third mold member is opened. A two-color molding method for a cover in a cassette tape storage case, wherein a mold member is moved to a position outside a movement locus at the time of release of a molded pocket portion of a cover to release the cover. 2. A first surface portion, a second surface portion bent from an edge of the first surface portion, and the first surface portion bent from an edge of the second surface portion.
A two-color molding die apparatus for a cover, wherein a pocket portion is formed between a third surface portion facing the surface portion and is pivotally attached to the base to constitute a cassette tape storage case.
A first mold member forming an outer surface on the side opposite to the pocket portion of the surface portion, and moving in a direction intersecting the first surface portion and the third surface portion and parallel to the second surface portion with respect to the first mold member; A second mold member capable of forming outer surfaces of the second surface portion and the third surface portion; and a second mold member movable in a direction parallel to the first surface portion and the third surface portion with respect to the second mold member. A third mold member forming an inner surface of the pocket portion and the first surface portion; and a third mold member movably penetrated through the third mold member in a direction intersecting the moving direction thereof and moving the third mold member. A fourth mold member movable outside the locus and forming the inner surface of the first surface portion; and a fourth mold member movably provided on the second mold member, the fourth mold member having a cavity wall formed of a cover. A stopper provided at a position to be an inner surface of the first surface portion. Two-color molding die apparatus of the cover in Totepu storage case.