JP2882169B2 - Molding - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molded product such as a cover of a compact disk storage case.

[0002]

2. Description of the Related Art FIG. 4 shows an example of a conventional compact disk storage case. This compact disc storage case is a thin type for storing two discs. In FIG. 1, reference numeral 1 denotes a compact disk, which has an opening 2 at the center. The compact disk storage case includes a base 6 and a pair of covers 7 rotatably supported on both sides (upper and lower surfaces in the figure) of the base 6. Compact disc 1 between cover 7
Are detachably accommodated. The base 6 is a resin molded product, and has a substantially rectangular substrate portion 11 positioned in parallel with the compact disk 1 stored therein.
Side walls 12 formed on both left and right edges of the substrate portion 11, respectively.
It consists of These side walls 12 are formed in both directions (upward and downward in the drawing) orthogonal to the substrate portion 11 and have a substantially T-shaped cross section with the substrate portion 11.
At the center of the substrate portion 11, there are formed disk holding portions 13 projecting from both sides of the substrate portion 11 to hold the compact disk 1 detachably. These disk holding portions 13 are composed of a plurality of claws radially positioned and capable of being elastically displaced in the radial direction thereof, and are engaged with the opening holes 2 of the compact disk 1 in a freely detachable manner. Further, finger insertion holes 14 are formed at four corners of the substrate portion 11 so that the compact disk 1 can be gripped when the disk 1 is attached or detached. Further, the front and rear side edges of the substrate portion 11 are formed as protruding edges 15 projecting in opposite directions to each other, and the outer surface of the protruding edge 15 is provided so that a finger can be put on the cover 7. A depression 16 is formed. At the same time, both side edges 12 are provided on both side walls 12.
The bearing holes 17 are formed respectively corresponding to the base plates 11 with the recessed engagement receiving portions 18 therebetween.
Are formed on the inner surfaces, respectively.

The two covers 7 are molded products of a transparent resin, and have the same shape. As shown in FIGS. 5 to 7, each cover 7 has a substantially rectangular first surface portion 21 positioned in parallel with the compact disk 1 stored therein, and parallel left and right ends of the first surface portion 21. A second surface portion 22 bent perpendicularly from the edge, and a third surface portion 23 bent perpendicularly from the rear edge of the first surface portion 21 to the same side as the second surface portion 22.
And a fourth bend perpendicularly from an end edge of the third surface portion 23 opposite to the first surface portion 21 and facing in parallel with the first surface portion 21.
It consists of a surface part 24. The second surface portion 22 and the third
The surface portion 23 and the fourth surface portion 24 are integrally continuous. On the outer surface of both the second surface portions 22, a support shaft 25 is provided at an end on the third surface portion 23 side.
Are respectively formed to protrude. And these spindles 25
Are rotatably fitted in opposed bearing holes 17 of the base 6, and a cover 7 is pivotally mounted on the base 6. Further, a pair of long holes 26 are respectively formed in the second surface portions 22 along the first surface portion 21. As a result, the edge of each of the second surface portions 22 along each of the long holes 26 is the second edge.
The elastic piece 27 is elastically displaceable in a direction intersecting with the surface portion 22. Further, a bulging portion bulging in an arc shape to a position facing the first surface portion 21 is provided at a central portion in a longitudinal direction of each elastic piece 27.
28 are formed respectively. These bulging portions 28 are for holding a label on the inner surface side of the first surface portion 21 together with the fourth surface portion 24. In the conventional cover 7, the width of the elastic piece 27 is constant from the center in the longitudinal direction to both ends. In addition, locking projections 29 are formed on the outer surfaces of the two elastic pieces 27 located apart from the fourth surface portion 24, respectively. The locking projections 29 are engaged with the engagement receiving portions 18 of the both side walls 12 of the base 6 to hold the cover 7 closed with respect to the base 6. A cutout portion 30 is formed at the edge of both second surface portions 22 between the elastic pieces 27.

Next, a mold apparatus for molding the cover 7 will be described with reference to FIGS. This mold apparatus includes a fixed mold member 31, a movable mold member 32, a first slide core 33, and a plurality of second slide cores 34. A cavity 35 having the shape of the cover 7 is formed between the side mold member 31, the movable mold member 32, the first slide core 33, and the second slide core 34. The fixed mold member 31 has a gate 36 opening to the cavity 35.
Are formed. The fixed mold member 31 includes a cover 7.
The outer surface of the first surface portion 21 is formed. The movable mold member 32 is parallel to the second surface portion 22 and the third surface portion 23 and perpendicular to the fourth surface portion 24 with respect to the fixed mold member 31 (the vertical direction in FIGS. 6 and 7). ) To form the outer surfaces of the third surface portion 23 and the fourth surface portion 24. The first slide core 33 is a movable mold member.
The first surface portion 21, the second surface portion 22, and the third surface portion 24 are parallel to the second surface portion 32 and are movable in a direction perpendicular to the third surface portion 23. The inner surface and the inner surface of the elastic piece 27 are formed. The second slide core 34 is attached to the movable mold member 32 so as to be movable in a direction parallel to the first surface portion 21 and orthogonal to the second surface portion 22. The outer surface of the piece 27 is formed. That is, the second slide core 34
Has a convex portion 41 forming the elongated hole 26 and a convex portion 42 projecting further from the convex portion 41 and forming an outer surface of the elastic piece 27. On the other hand, the first slide core 33 has a concave portion 43 in which the convex portion 42 of the second slide core 34 is fitted and forms a surface other than the outer surface of the bulging portion 28. Angular pins 46, 47 fixed to the fixed mold member 31 are slidably inserted into the slide cores 33, 34, whereby the fixed mold member 31 and the movable mold member 31 are moved. In association with opening and closing with the movable mold member 32, the slide core 33,
34 move. The diameter of the through hole 46 of the first slide core 33 is larger than the diameter of the angular pin 48 inserted into the through hole 46. Accordingly, when the fixed mold member 31 and the movable mold member 32 start opening the mold, the movement start of the second slide core 34 is delayed more than the movement start of the first slide core 33. .
Locking blocks 50 and 51 for holding the slide cores 33 and 34 are fixed to the fixed mold member 31. FIG. 5 shows a moving direction of the slide cores 33 and 34 when the mold is opened. In the figure, arrow a indicates the direction of movement of the first slide core 33, arrow b1 indicates the direction of movement of the second slide core 34 for one second surface 22, and arrow b2 indicates the other second surface. This is the moving direction of the second slide core 34 for 22. The second slide core 34 may be provided one for the whole second surface portion 22. May be provided.

Next, the operation of the above configuration will be described. When the cover 7 is formed, as shown in FIGS. 6 and 7, the fixed mold member 31 and the movable mold member 31 are used.
The fixed side mold member 31, the movable side mold member 32, the first slide core 33 and the second slide core
A cavity 35 is formed between 34. After that, the molten resin is poured into the cavity 35 from the gate 36. And
After the resin filled in the cavity 35 is solidified, the fixed mold member 31 and the movable mold member 32 are opened. With the opening of the mold, first, the fixed-side mold member 31 separates from the molded cover 7. At the same time, as shown by a chain line in FIG. 7, the angular pin 47 fixed to the fixed-side mold member 31 is used.
In the direction in which the second slide core 34 is separated from the second surface portion 22 and the first slide core 33 of the cover 7
Move to b1 and b2. Next, after the convex portion 42 of the second slide core 34 comes off from the concave portion 43 of the first slide core 33, that is, the second slide core 34 is moved to the first slide core 33.
After moving to a position that does not hinder the movement of the
An angular pin 46 fixed to 31 abuts on the right side of the peripheral surface of the through hole 48 of the first slide core 33 in the drawing, and is driven by the angular pin 46 to cause the first slide core 33 to move to the third surface portion 23. Move in the direction a away from. Then, as shown by a chain line in FIG. 6, after the first slide core 33 comes off from between the first surface portion 21 and the fourth surface portion 24, it is protruded by a protruding member (not shown), and the cover 7 is movable. It is separated from the side mold member 32 and the first slide core 33. By the way, the bulging portion 28 on the second surface portion 22 of the cover 7 is
Is bulged to a position opposed to the first surface portion 21, and therefore bites into the recess 43 before the movement of the first slide core 33 when the mold is opened, and the first slide core when the mold is opened. An undercut occurs in the moving direction of the core 33. Therefore, as the first slide core 33 moves at the time of opening the mold, as shown by a chain line in FIG.
Is elastically displaced outward, so that the bulging portion 28
From the recess 43 of the slide core 33. That is, the first
When the first slide core 33 moves,
The swelling portion 28 is forcibly pulled out of the opening.

[0006]

When the cover 7 of the compact disk storage case is formed as described above, the bulging portion 28 is moved by the first slide core 33 in a direction perpendicular to the moving direction (vertical direction in the drawing). Of the recess 43 along with the movement of the first slide core 33.
When the swelling portion 28 comes off while being elastically displaced, the elastic piece 27 having the swelling portion 28 cannot be freely displaced in the vertical direction in the figure, and the upper and lower surfaces of the elastic piece 27 Rub. As a result, a force is applied to the elastic piece 27 in the vertical direction in the figure, and the elastic piece 27 is distorted.
Is easily damaged by cracks. In particular, cracks are likely to occur at the bases at both ends of the elastic piece 27, and in some cases, the bases may be broken. Moreover, in the conventional cover 7, the width of the elastic piece 27 is constant from the center in the longitudinal direction to both ends, and the strength of the base of the elastic piece 27 where cracks are apt to occur is weak, and The elastic piece 27 is liable to be damaged since the central portion of the bulging portion 28 having a larger undercut amount in the moving direction of the first slide core 33 is less likely to be deformed.

The present invention is intended to solve such a problem, and the second surface portion and the third surface portion are bent to the same side from the edge of the first surface portion like a cover of a compact disk storage case. At the same time, the fourth surface portion facing the first surface portion is bent from the edge of the third surface portion, and an elastic piece is formed in the second surface portion by a long hole along the first surface portion. In a molded product having a bulging portion bulging to an opposing position, a mold member forming the inner surface of each of the surface portions moves along the first surface portion and the second surface portion during molding, and An object of the present invention is to prevent the elastic pieces from being damaged such as cracks when the bulging portion is forcibly removed.

[0008]

In order to achieve the above object, the present invention provides a first surface portion, a second surface portion bent from a pair of parallel edges of the first surface portion, and a first surface portion. A third surface portion bent from the other edge to the same side as the second surface portion, and a fourth surface portion bent from the edge of the third surface portion and opposed to the first surface portion.
And a long hole is formed in the second surface along the first surface, and an edge of the second surface along the long hole is formed as an elastic piece. In the molded article having a bulging portion bulging to a position facing the first surface portion, the elastic piece is formed in a shape having a width gradually increasing from a center toward both ends.

[0009]

In the molded article of the present invention, when the molded article is released from the mold at the time of molding, for example, the mold member forming the inner surface of each surface of the molded article moves along the first surface and the second surface. Then, the bulging portion bulging from the second surface portion to a position facing the first surface portion is elastically displaced in a direction in which the elastic piece having the bulging portion intersects with the second surface portion. Is forcibly removed from the mold member forming the inner surface of the mold. At this time, the elastic piece has a shape that gradually increases in width from the center toward both ends, and the strength of the roots at both ends of the elastic piece, which tends to cause cracks, is high, and the elastic member has an underside with respect to the moving direction of the mold member. Since the central portion of the bulge having a larger cut amount is easily deformed, the elastic piece is prevented from being damaged.

[0010]

Hereinafter, one embodiment of the molded article of the present invention will be described.
This will be described with reference to FIG. The molded product of this embodiment is the cover 7 of the compact disk storage case. Since the cover 7 has substantially the same configuration as the cover 7 described above with reference to FIGS. 4 to 6, the corresponding parts are denoted by the same reference numerals and description thereof will be omitted. In the following description, FIG. 4 to FIG. 6 are also cited. In FIG. 1, which is a side view showing a part of the second surface portion 22 of the cover 7, reference numeral 61 denotes a long hole, 62 denotes an elastic piece, and 63 denotes a bulging portion. It is almost the same. However, the edge of the elastic piece 62 on the first surface portion 21 side (upper side in the drawing) is a concave edge 64 curved in a smooth arc shape and concavely. Thus, the width of the elastic piece 62 in the direction (vertical direction in the drawing) orthogonal to the first surface portion 21 gradually increases from the center in the longitudinal direction to the root portions at both ends.

FIG. 2 shows an example of a mold apparatus for molding the cover 7. This mold device has substantially the same configuration as that of the mold device shown in FIGS. 5 to 7 described above, and the corresponding parts are denoted by the same reference numerals and description thereof will be omitted. . In the mold apparatus shown in FIG. 2, the second slide core 34 has a convex portion 66 forming the long hole 61 of the cover 7, and an elastic piece 63 projecting further from the convex portion 66.
The shape with the convex portion 67 forming the outer surface of the long hole 61 as described above.
And one that matches the shape of the elastic piece 63. On the other hand, also in the first slide core 33, the convex portion 67 of the second slide core 34 is fitted at the time of mold clamping, and the shape of the concave portion 68 forming a surface other than the outer surface of the bulging portion 63 is changed to the convex portion 67 and the convex portion 67. Bulge
It fits the shape of 63.

Next, the operation of the above configuration will be described. When the cover 7 is formed, the fixed-side mold member
With the mold opening between the movable mold member 31 and the movable mold member 32, as shown by a chain line in FIG. 2, after the convex portion 67 of the second slide core 34 comes off the concave portion 68 of the first slide core 33, 1 slide core
33 moves along the first surface portion 21 and the second surface portion 22 in the direction a away from the third surface portion 23. At this time, the elastic piece 62 having the bulging portion 63 is elastically displaced outward in the direction intersecting with the second surface portion 22, so that the bulging portion 63 is forcibly pulled out of the concave portion 68 of the first slide core 33. Is done.

According to the structure of the embodiment, since the width of the elastic piece 62 gradually increases from the longitudinal center of the elastic piece 62 to the roots at both ends, the elastic piece 62 which is liable to crack is originally formed. The strength of the base part of the base is improved. Further, since the width of the central portion of the bulging portion 63 having a larger undercut amount in the moving direction of the first slide core 33 is small, the central portion of the bulging portion 63 is easily deformed. From these facts, when the bulging portion 63 is forcibly removed from the concave portion 68 along with the movement of the first slide core 33 when the mold is opened, the elastic piece 62
Can be prevented from being damaged.

FIG. 3 shows another example of a mold apparatus for molding the cover 7. In this mold apparatus, the second
In the slide core 34, the convex portion 69 forming the elongated hole 61 of the second surface portion 22 of the cover 7 is extended, and this convex portion 69 is at least the first portion of the bulging portion 63 of the elastic piece 62 when the mold is clamped. The entire surface (upper surface in the drawing) on the surface portion 21 side is located between the inner surface of the first surface portion 21 facing this surface. On the other hand, the first slide core 33 has a concave portion 70 into which the convex portion 69 is fitted at the time of mold clamping.

In the mold apparatus shown in FIG. 3, the convex portions 67 and 69 of the second slide core 34 are formed by the concave portions 68 and 69 of the first slide core 33, as shown by a chain line in FIG. 70
, That is, the second slide core 34 is
To the position where the movement of the slide core 33 is not hindered, and the swelling portion 63 of the elastic piece 62 and the first surface portion 21 facing the swelling portion 63.
After moving until the protrusion 69 comes off from the inner surface of the
Slide core 33 moves along the first surface portion 21 and the second surface portion 22 in the direction a away from the third surface portion 23. At this time,
The bulging portion 63 is formed in the concave portion of the first slide core 33 by the elastic piece 62 being elastically displaced outward along the first surface portion 21.
It is forcibly removed from 68. At that time, as described above,
Since the convex portion 69 of the second slide core 33 is removed from between the inner surface of the first surface portion 21 where the bulging portion 63 faces the bulging portion 63,
The elastic piece 62 can be freely displaced in a direction approaching the first surface 21 (upward in the figure). In conjunction with this, the friction between the first slide core 33 and the surface (lower surface in the drawing) of the elastic piece 62 opposite to the first surface portion 21 is reduced, that is, the lower surface of the elastic piece 62 with respect to the lower surface in the drawing. Since the resistance applied from the first slide core 33 is reduced, the force applied to the elastic piece 62 in the vertical direction in the figure is also reduced, and the elastic piece 62 is smoothly displaced in the direction along the first surface 21. Thereby, the elastic piece
The occurrence of distortion in the elastic piece 62 is prevented, and the occurrence of breakage such as a crack in the elastic piece 62 is more reliably prevented.

It should be noted that the present invention is not limited to the above embodiment, and various modifications can be made. For example,
The present invention is not limited to the cover 7 of the compact disc storage case as described above, and the second surface portion and the third surface portion are bent to the same side from the edge of the first surface portion, and the second surface portion and the third surface portion are bent from the edge of the third surface portion. A fourth surface portion facing the first surface portion is bent, and an elastic piece is formed in the second surface portion by a long hole along the first surface portion, and a bulging portion bulging to a position facing the first surface portion is formed on the elastic piece. It can be applied to formed molded articles in general.

[0017]

According to the present invention, the second surface portion and the third surface portion are bent to the same side from the edge of the first surface portion, and the fourth surface portion facing the first surface portion from the edge of the third surface portion. Is bent, and an elastic piece is formed in the second surface portion by a long hole along the first surface portion, and a bulging portion bulging to a position facing the first surface portion is formed on the elastic piece. Is formed in a shape that gradually increases in width from the center to both ends, so that the strength of both ends of the elastic piece, which tends to crack due to displacement from the beginning, increases, and the center of the bulging part is easily deformed. Therefore, when the mold member forming the inner surface of each of the surface portions moves along the first surface portion and the second surface portion during molding and the bulging portion is forcibly removed from the mold member, a crack or the like in the elastic piece may occur. Can be prevented from being damaged.

[Brief description of the drawings]

FIG. 1 is a side view of an embodiment of a molded product of the present invention, showing a vicinity of an elastic piece of a cover of a compact disc storage case which is a molded product.

FIG. 2 is a cross-sectional view showing an example of a mold device for molding the cover.

FIG. 3 is a cross-sectional view showing another example of a mold device for molding the cover.

FIG. 4 is a perspective view of a conventional compact disk storage case.

FIG. 5 is a bottom view of the cover.

FIG. 6 is a cross-sectional view showing an example of a conventional mold apparatus for molding a cover, and corresponds to a cross section AA in FIG.

7 is a cross-sectional view of the same, and corresponds to a BB cross section of FIG. 5;

[Explanation of symbols]

 7 Cover (molded product) 21 First surface 22 Second surface 23 Third surface 24 Fourth surface 61 Long hole 62 Elastic piece 63 Swelling portion

Claims (1)

(57) [Claims] 1. A first surface portion, a second surface portion bent from a pair of parallel edges of the first surface portion, and a second surface portion bent from another edge of the first surface portion to the same side as the second surface portion. A third surface portion and a fourth surface portion bent from an edge of the third surface portion and opposed to the first surface portion.
And a long hole is formed in the second surface along the first surface, and an edge of the second surface along the long hole is formed as an elastic piece. In a molded product having a bulging portion bulging to a position facing the first surface portion, the elastic piece is formed to have a shape whose width gradually increases from a center toward both ends.