JPH0761668B2 - Mold device for molding half case for floppy disk - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a mold device for molding a half case for a floppy disk, which molds a half case for accommodating a disk-shaped storage disk body.

[Conventional technology]

Conventionally, when molding this type of half case for a floppy disk, a gate (injection port) is provided at a position corresponding to the four corners of the surface of the half case, and molten resin is supplied from the four-point gate into the cavity. Then, the half case is molded, and therefore, the molten resin injected from the four gates flows toward the central portion of the half case.

[Problems to be solved by the invention]

However, in the case of molding with a four-point gate as described above, especially in a half case (upper case) where there is no through hole in the central portion, degassing in the central portion is likely to be insufficient, and There is a wet surface,
Alternatively, there is a problem that pressure is not uniformly applied to the molded product, and the molded product is warped.

The present invention has been made in view of the above circumstances, and an object thereof is to allow the resin to smoothly flow in the cavity and to smoothly perform degassing,
It is an object of the present invention to provide a mold device for molding a half case for a floppy disk, which can prevent defects such as a wetting surface and warpage in a molded product.

[Means for solving problems]

In order to achieve the above-mentioned object, the present invention provides two injection ports for the molten resin into the cavity, and stores these injection ports in a portion of the shutter area that is covered by a normal shutter for storing a storage disk body. It is arranged on the engraving surface of the die corresponding to the positions outside the portion and on both sides of the window for introducing the magnetic head.

[Work]

In the mold device for molding the half case for the floppy disk of the present invention, the injection port to the cavity of the molten resin is arranged on the engraved surface of the mold in a portion of the shutter area that is covered by the normal shutter, No traces of the inlet are exposed. Further, since the inlet is arranged outside the storage portion of the storage disk body, the trace of the inlet does not interfere with the storage of the storage disk body. further,
Since two injection ports are provided and these injection ports are arranged on both sides of the window for introducing the magnetic head, the molten resin is sufficiently supplied to the thin portion and the flow of the molten resin is uniform. Orientation is adjusted so that pressure is uniformly applied to each part, and degassing is smoothly performed.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a sectional view showing a part of a mold device for molding an upper case 1 for a floppy disk as shown in FIGS. 2 and 3. The upper case 1 is formed in a substantially square thin-walled surface, and a surface 1a has a shutter area 1b for mounting the shutter 6 and a label area 1c for sticking a label. Each is formed to be slightly depressed from the other portions. Further, the upper case 1 is formed with a window portion 1d for introducing a magnetic head and a hole portion 1e for a light protector, respectively. further,
On the inner surface 1f side of the upper case 1, an outer frame portion 1g is formed over substantially the entire outer edge portion thereof, and an arc-shaped rib portion 1h is formed so as to be continuous with the outer frame portion 1g. The inner side of the rib portion 1h is a disc body storage portion 1i for storing a disc-shaped storage disc body, and the outer side of the rib portion 1h is the lower left portion of FIG. A spring storage portion 1j for storing a spring for biasing the shutter 6 to the right.

The mold for molding the upper case 1 configured as described above is
As shown in FIG. 1, a fixed template 2 having an engraved surface for forming the surface 1a of the upper case 1, and an inner surface 1f of the upper case 1.
And a movable mold plate 3 having an engraved surface for forming a mold, and an injection port (gate) 5 for injecting a molten resin into a cavity 4 formed between these mold plates 2 and 3 is shown in FIG. As shown in FIG. 3, the shutter area 1b of the upper case 1 is covered with the shutter 6 urged by the spring (shown as a gate mark 1k in FIG. 2) and shown in FIG. As shown in FIG. 3, the outer case 1i of the upper case 1 is located as close to the center 7 of the upper case 1 as possible (in FIG. 3, a convex portion facing the gate mark 1k).
(Indicated as 1l) and two positions separated on both sides of the window 1d for introducing the magnetic head are formed on the engraved surface of the fixed template 2. In FIG. 1, the upper case 1 in the cavity 4 shows a cross section taken along the line I-I in FIG. 2 and a cross section taken along the line I′-I ′ in FIG. Shows.

When the upper case 1 for a floppy disk is molded using the mold apparatus configured as described above, the fixed mold plate 2 and the movable mold plate 3 are closed as in the conventional case, and both mold plates are closed. 2,
Molten resin is supplied from a pair of injection ports 5 into the cavity 4 formed by 3. At this time, since the injection port 5 is arranged in a portion of the shutter area 1b of the upper case 1 covered by the shutter 6, the trace of the injection port 5 is not exposed. Further, since the injection port 5 is arranged outside the disk body storage portion 1i, the trace of the injection port 5 does not interfere when the storage disk body is stored. Further, two injection ports 5 are provided, and the injection ports 5 are arranged at positions separated from each other on both sides of the window for introducing the magnetic head, so that the molten resin is sufficiently supplied to the thin portion. , The flow of the molten resin is in one direction (indicated by the two-dot chain line arrow in FIG. 2)
The pressure is evenly applied to each part, and degassing is easily performed. Therefore, it is possible to obtain a product of good quality without causing defects such as a wetting surface and warpage of the molded product.

Although the molding of the upper case 1 has been described in the above embodiment, the lower case has substantially the same structure as that of the upper case 1 except that the central case has a through hole. Even in the molding of the lower case, it is clear that a smooth resin flow can be secured even if there is a through hole in the central portion by providing the molten resin injection port in the same portion as above. That is, when molding the lower case, the same operational effects as those of the upper case 1 can be obtained, and the present invention can be applied.

〔The invention's effect〕

As described above, according to the present invention, the injection port for the cavity of the molten resin is arranged on the engraved surface of the mold in the portion of the shutter area that is covered by the normal shutter, so that the trace of the injection port is exposed. It has the effect of not doing. Further, since the injection port is arranged outside the storage portion of the storage disk body, there is an effect that the trace of the injection port does not interfere with the storage of the storage disk body. Furthermore, two injection ports are provided, and these injection ports are arranged at positions separated from each other on both sides of the window for introducing the magnetic head. Therefore, the molten resin injected from this injection port is
The gas is discharged smoothly by supplying the resin sufficiently to the thin wall and smoothing the resin flow, and it is possible to prevent defects such as wetting and warpage in the molded product, and also the number of gates. It has an excellent effect that it is possible to reduce the number of parts and realize a large number of pieces.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention, FIG. 2 and FIG.
The figure shows an example of an upper case molded using the mold apparatus of the present invention. FIG. 2 is a plan view seen from the surface side of the upper case, and FIG. 3 is a bottom view seen from the inner surface side of the upper case. is there. 1 ... Upper case, 1a ... Surface, 1b ... Shutter area, 1i ... Disc housing, 2 ... Fixed template, 3 ... Possible template, 4 ... Cavity, 5 ... Filling port (Gate), 6 ... Shutter, 7 ... Center.

Claims (1)

[Claims] 1. A molten resin is supplied to a cavity in a mold, and a shutter area portion for mounting a shutter, a window portion for introducing a magnetic head, and a storage portion for storing a disk-shaped storage disk body are provided. A mold apparatus for molding a half case for a floppy disk, comprising: two injection ports into the cavity for the molten resin;
These inlets are located on the engraved surface of the mold corresponding to the positions outside the storage part of the storage disk body and on both sides of the window for introducing the magnetic head in the part of the shutter area that is normally covered by the shutter. A mold device for molding a half case for a floppy disk, which is arranged.