JP2001341171A - Injection molding apparatus for injection-molding molded article having ultrathin-walled part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an injection molding apparatus for injection molding a molded article having an ultrathin-walled part, capable of being simply cleaned when a solid in gas is bonded to the tip part of a gas venting pin or the periphery thereof to close a gas discharge route, without detaching a mold from the injection molding apparatus or disassembling the mold. SOLUTION: The tip part of a gas venting pin 16 is notched longitudinally and a corresponding mating piece 16a is mated with this notch part 16b to constitute the tip part. The tip part of the gas venting pin 16 is made freely accessible with respect to a cavity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to injection molding of a molded article having an ultra-thin wall, such as a memory card. More specifically, without disassembling the mold,
The present invention relates to an injection molding device capable of cleaning a tip portion of a degassing pin.

[0002]

2. Description of the Related Art In recent years, with the development of electronic devices, audio devices for music and the like have been developed, and very thin and small memory cards have been required. A memory card is called an IC card, a stick memory card, a smart card, or the like, and has a micro IC chip (electronic component) incorporated therein. This type of memory card must be made of a synthetic resin and have a rigid form in consideration of protection and handling of the internal IC chip.

The portion of the memory card on which the IC chip is mounted is an ultra-thin portion of 0.7 mm or less. In the injection molding of a memory card having such an ultra-thin portion, in order to injection-mold a molded product having an ultra-thin portion, a gas vent hole is provided in a thin portion forming portion constituting a mold of the molded product. At the same time, a vertically separated gas vent pin is inserted into the gas vent hole, and the gas in the cavity is determined from the gap between the gas vent pin and the gas vent hole and the gap at the joint of the gas vent pin. An injection molding apparatus for forcibly discharging the waste gas is used.

However, in the conventional injection molding apparatus, the solid content contained in the exhaust gas adheres to the joint of the pin serving as a gas vent path and the gap between the pin and the hole, particularly the tip of the pin. However, the deposits obstruct the path for degassing, and as a result, the gas in the cavity cannot be sufficiently depleted, resulting in difficulties in high-precision molding. Therefore, in the conventional injection molding apparatus, it is necessary to perform a cleaning operation of removing the mold at regular intervals and disassembling the mold to remove the adhered matter attached to the tip of the pin. And the productivity was greatly hindered.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides an injection molding apparatus capable of cleaning a tip portion of a degassing pin without disassembling a mold. It is intended for.

[0006]

Means for Solving the Problems In order to achieve the above object, the present inventors, when injection molding a molded article having an ultra-thin portion, for example, a memory card, use an ultra A gas vent hole is provided in the thin portion forming portion, and a gas vent pin is inserted into this gas vent hole,
In an injection molding apparatus configured to discharge gas in a cavity from a gap between the degassing pin and the degassing hole, a tip portion of the degassing pin is allowed to protrude and retract into the cavity, and the An injection molding apparatus characterized in that the tip can be disassembled. In addition, the present invention has proposed an injection molding apparatus characterized in that the degassing pin is caused to move in and out with the pushing operation of the extrusion mechanism of the apparatus.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an injection molding apparatus according to the present invention will be described in detail according to embodiments shown in the drawings.

FIG. 1 shows a memory card 1 as a molded article molded by the injection molding apparatus of the present invention. The memory card 1 has an ultra-thin portion 2 on which an IC chip is mounted. Hereinafter, the injection molding apparatus of the present invention will be described by taking the injection molding of the memory card 1 as an example.

As shown in FIGS. 2 and 3, an injection molding apparatus (hereinafter simply referred to as an apparatus) 11 of the present invention includes a mold 12 and a filling mechanism (illustration) for filling a cavity C of the mold 12 with a molten resin. No), a gas discharge mechanism including a gas discharge path (not shown) for discharging gas in the cavity C, and an extruding mechanism 14 for moving a gas release pin 16 described later up and down.

The device 11 of the present invention has a characteristic portion in the mold 12. That is, the mold 12 includes an upper mold (not shown), a lower mold 12a, and an extrusion plate 12c.
The upper mold (not shown) and the lower mold 12a are provided with a thin portion forming portion 12b for forming an ultra thin portion. A gas vent hole 15 is provided in the thin portion forming portion 12b of the lower mold 12a.

As shown in FIGS. 2 and 3, the gas vent hole 15 is a substantially cylindrical hole penetrating the lower mold 12a in the thickness direction, and a gas vent pin 16 is provided in the gas vent hole 15. Inserted. The top surface of the tip of the gas vent pin 16 is fixed at a position where the surface on the cavity C side of the thin portion forming portion 12b of the lower mold 12a is flat.

The gas vent pin 16 has a structure in which the tip portion can be disassembled in the vertical direction. In the case of the degassing pin 16 shown in FIGS. 4, 5 and 6, the tip of the pin 16 is notched in the vertical direction, and the tip is formed by fitting a matching piece 16a corresponding to the notch 16b. It is supposed to be. The disassembly structure of the tip portion of the pin 16 is not limited to the one shown in FIGS. 4 to 6. For example, an engagement protrusion is provided on the inner surface of the matching piece pin 16 a, and the matching piece 16 a is connected to the pin 16 tip portion. The notch 16b can be freely changed, for example, by providing an engagement hole for engaging with the engagement protrusion.

When the gas venting pin 16 is inserted and fixed in the gas venting hole 15, the gap between the gas venting pin 16 and the gas venting hole 15, the cutout portion 16 b at the tip of the gas venting pin 16 and the mating piece are formed. A slight gap 17a, 17b is formed at the joint of 16A, and these gaps 17a, 17b are formed.
The gas in the cavity C of the mold 12 is discharged through 7b.

An air reservoir 18 is provided inside the distal end portion of the degassing pin 16, and gas in the cavity C discharged through the gaps 17 a and 17 b enters the air reservoir 18. . Further, the side surface of the gas vent pin 16 is provided with a diameter smaller than that of the distal end portion, and a passage 17c serving as a gas discharge path is formed between the gas vent pin 16 and the gas vent hole 15. The gas in the air reservoir 18 enters the passage 17c from below the air reservoir 18 and is discharged out of the device 11 via a gas discharge path (not shown) provided in the device 11 connected to the passage 17c. Has become.

In this case, a vacuum pump (not shown) is connected to a gas discharge path (not shown) of the apparatus 11, and the gas in the cavity C is subjected to a negative pressure by the vacuum pump (not shown). Are forcibly discharged.

The tip of the pin 16 has a cavity C
It is possible to appear inside. The structure for causing the pin 16 to protrude and retract into the cavity C is arbitrary. In the embodiment shown in FIGS. 4 to 6, the lower end of the pin 16 is pushed by the pushing mechanism 14 already provided in the device 11, and the pushing plate 1 of the mold 12 is pushed.
2c was pushed out, and the pin 16 was moved up and down in conjunction with this. The mechanism for causing the pins to move in and out is not limited to this, and a new hydraulic cylinder may be provided in the device 11 and the pins 16 may be moved up and down by the cylinder.

In the apparatus 11 configured as described above, when the pin 16 needs to be cleaned, the pushing mechanism 14 is required.
Thus, the tip of the degassing pin 16 protrudes into the cavity C, the screw 19 at the tip of the protruding pin 16 is loosened, the fitting piece 16a is removed from the notch 16b, and the tip is disassembled. The solid matter attached to the tip of the pin 16 can be cleaned very easily.

It should be noted that the present invention is not limited to the embodiment shown in the drawings. For example, the gas vent pin can be freely disassembled in a vertical direction and a horizontal direction. Can be changed.

[0019]

According to the injection molding apparatus of the present invention, when cleaning is required, the tip of the degassing pin is projected into the cavity without disassembling the mold, and the projected tip is disassembled. It can be easily cleaned and maintenance is extremely easy.

[Brief description of the drawings]

[Figure 1] Memory card

FIG. 2 is an injection molding apparatus.

FIG. 3 is an injection molding apparatus.

Fig. 4 Shape of vent pin

Fig. 5 Shape of vent pin

FIG. 6 shows the shape of a vent pin.

[Explanation of symbols]

 12: Die 12a: Die 12b: Thin-walled portion 12c: Extruded plate 14: Extrusion mechanism 15: Degassing hole 16: Degassing pin 16a: Mating piece 16b: Notch 17a, 17b: Void 17c: Passage 18: Air Pool 19: Screw

Claims (2)

[Claims] In order to injection-mold a molded product having an ultra-thin portion, a gas vent hole is provided in an ultra-thin portion forming portion constituting a mold of the molded product, and a gas vent pin is provided in the gas vent hole. In an injection molding apparatus that discharges gas in the cavity from the gap between the gas vent pin and the gas vent hole, the tip of the gas vent pin is allowed to protrude and retract into the cavity, An injection molding apparatus, wherein a tip portion of the degassing pin can be disassembled. 2. The injection molding apparatus according to claim 1, wherein the degassing pin is caused to move up and down with the pushing operation of the pushing mechanism of the apparatus.