JPH10286846A - Molding device of disc molded article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the galling between an ejector and a male cutter by a method wherein the ejector of a movable mold is arranged outside a fixed sleeve, which is provided at the outer periphery of the male cutter and, at the same time, the outer periphery is set to be larger than the outer periphery of the inner peripheral stamper keeper of a fixed mold. SOLUTION: The ejector 22 of a movable mold is arranged outside a fixed sleeve 23, which is provided at the outer periphery of a male cutter 24. At the same time, the outer periphery of the ejector 22 is set to be larger than the outer periphery of the inner peripheral stamper keeper 12 of a fixed mold 10. The ejector 22 of the movable mold 20 is arranged outside and through the fixed sleeve 23. Thus, the direct interference of the male cutter 24 with the ejector 22, which has slid against the male cutter, is evaded, resulting in allowing to eliminate the cause of scoring. At the same time, by arranging the ejector 22 outside the fixed sleeve 23, the ejection at the portion further outward from the center hole portion, which is formed with the male cutter 24, becomes possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for molding a disk molded product, and more particularly to an improvement in an ejector mechanism thereof.

[0002]

2. Description of the Related Art For example, when molding a disk molded product such as a CD or DVD, as shown in FIG. 3 of the accompanying drawings, a stamper S is attached to a fixed side mirror block 51 of a fixed mold 50 to perform molding. Have been done. In the drawing, reference numeral 52 denotes a stamper inner peripheral holder (note that a stamper outer peripheral holder is not shown);
4 represents a sprue bush. Reference numeral 60 denotes a movable type, 61 denotes a movable mirror block, 62 denotes a fixed sleeve, 63 denotes an ejector, 64 denotes a male cutter, 65 denotes a center pin, C denotes a disk molded product cavity, and G denotes a gate.

In this disk forming apparatus, first,
As shown in FIG. 3, the resin material M is injected and filled into the disc molded product cavity C from the sprue hole of the sprue bush 54. After the injection is completed, the male cutter 64 and the center pin 65 of the movable die 60 move forward to cut the gate. Then
As shown in FIG. 4, the movable die 60 is moved, and after the mold is opened, the ejector 63 and the center pin 65 are advanced, and the disk molded product D (and the sprue molded portion P) is protruded from the movable mirror block 61.

[0004] Generally, the molding of this type of disk molded product D is generally performed in the above steps. In this conventional molding, when the disk molded product D protrudes after the gate cut, the ejector is ejected. In some cases, galling may occur in 63, or mold release unevenness or warpage of the disk molded product D may occur.

[0005] As shown in the figure, the ejector 63 is disposed directly adjacent to the male cutter 64 as a sliding member, and when the disk molded product D projects, it slides with respect to each other. Conceivable. Further, the fact that the ejector 63 is disposed immediately around the male cutter 64 means that the portion just outside the center hole of the disk molded product D is protruded by the ejector 63, and the narrow disk molded product D having a wide face plate is narrow. Since the pressing force is applied at the center, it is difficult to uniformly release the entire mold. For example, in a general disk molded product D, the diameter of the molded product is 120 mm, while the diameter of the ejector 63 is 19 mm, and the ejecting force of the ejector 63 exerts a larger force on the central portion of the molded product. It is conceivable that the product D may have warpage or mold release unevenness.

[0006]

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-mentioned problems, and occurs between the ejector and the male cutter, particularly when the disk molded product is released from the mold. An object of the present invention is to provide a novel disk molded product molding apparatus that can eliminate galling and can also eliminate warpage and mold release unevenness of a molded product.

[0007]

That is, the present invention provides:
After the molten resin material is injected into the disk molded product cavity in which the stamper is arranged on the fixed side mirror block via the inner peripheral stamper retainer provided in the fixed mold, and the male cutter provided in the movable mold is advanced to perform gate cutting, In a device in which the mold is opened and the disc molded product is protruded from the movable side mirror block by an ejector provided on the movable die, the movable type ejector is disposed outside a fixed sleeve provided on the outer periphery of the male cutter. And an outer periphery of the ejector is formed larger than an outer periphery of the inner peripheral stamper retainer of the fixed die.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a cross-sectional view of a main part during injection molding of a disk molding apparatus according to one embodiment of the present invention, and FIG. 2 is a cross-sectional view of a main part showing a protruding state of the disk molded product.

The disk molding apparatus in the embodiment is an apparatus used for molding a disk molded product such as a CD or a DVD as described above.
Denotes a fixed-side mirror block, 12 denotes a stamper inner peripheral press (note that the stamper outer peripheral press is not shown), 13 denotes a mess cutter, and 15 denotes a sprue bush. Reference numeral 20 denotes a movable type, 21 denotes a movable side mirror block, 2
2 is an ejector, 23 is a fixed sleeve, 24 is a male cutter, and 25 is a center pin. Symbol C indicates a molded product cavity, G indicates a gate, and S indicates a stamper.

[0010] This disk forming apparatus is similar to the above-described one in that the sprue bush 1 is inserted into the disk forming cavity C.
After injecting the resin material M from the sprue hole No. 5, the male cutter 24 of the movable mold 20 is advanced to cut the gate. Thereafter, the movable mold 20 is moved to open the mold, and as shown in FIG. 2, the movable ejector 22 and the center pin 25 are moved.
Moves forward to project the disk molded product D from the movable side mirror block 21 and discharge the sprue molded portion P.

In the apparatus of the present invention, as is apparent from the drawing, a movable ejector 22 is disposed outside a fixed sleeve 23 provided on the outer periphery of an male cutter 24, and the outer periphery of the ejector 22 is 10 is formed larger than the outer periphery of the inner stamper retainer 12.

That is, the ejector 22 of the movable mold 20
In the related art, as shown in FIG. 3, the is disposed directly adjacent to the male cutter, but in the present invention, the is disposed outside through the fixing sleeve 23. As a result, direct interference between the male cutter 24 and the ejector 22, which are members that slide together, can be avoided, and the cause of galling can be eliminated. At the same time, by arranging the ejector 22 outside the fixed sleeve 23, it is possible to protrude much more outside the center hole of the disk molded product formed by the male cutter 24. And most preferably,
By making the outer periphery of the ejector 22 larger than the outer periphery of the inner stamper retainer 12 of the fixed die 10, the force applied to the disk molded product D by the ejector 22 is applied to the entire surface of the disk molded product in the shape of a face plate. It is possible to prevent the molded article D from warping and releasing unevenness.

[0013]

As shown and described above, according to the present invention, it is possible to completely avoid the conventional ejector galling when the disc molded product is projected by the ejector. Also, by increasing the diameter of the protrusion by the ejector, unevenness of the pressing force of the disk molded product is minimized as much as possible. Unevenness can be prevented, and a higher quality disk molded product can be molded.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part during injection molding of a disk molding apparatus according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a main part of the disk molded product of FIG. 1 in a protruding state.

FIG. 3 is a partial cross-sectional view during injection molding of a conventional disk molding apparatus.

FIG. 4 is a partial cross-sectional view showing a protruding state of a disk molded product of the apparatus of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Fixed type 11 Fixed side mirror block 12 Stamper inner circumference presser 13 Mesquitter 15 Sprue bush 20 Movable type 21 Movable side mirror block 22 Ejector 23 Fixed sleeve 24 Osutter 25 Center pin C Molded product cavity G Gate D Disk molded product

Claims (1)

[Claims] 1. A molten resin material is injected into a disk molded product cavity in which a stamper is disposed on a fixed side mirror block via an inner peripheral stamper retainer provided on a fixed die, and an male cutter provided on a movable die is moved forward. After gate cut,
In a device in which the mold is opened and the disc molded product is protruded from the movable side mirror block by an ejector provided on a movable die, the movable type ejector is disposed outside a fixed sleeve provided on an outer periphery of the male cutter. And an outer periphery of the ejector is formed larger than an outer periphery of the inner peripheral stamper retainer of the fixed die.