JPH1119983A - Mechanism for dismounting disk substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of a couple and to eliminate troubles in sticking by the outside deformation of a disk substrate by a method in which the end surface of an ejector sleeve for ejecting the disk substrate from a mold after molding, when the disk substrate is absent, is contacted with the holding part of a tripper for holding and transferring the disk substrate. SOLUTION: A male cutter 4 is advanced with an ejector pin 5 during cooling and solidification of a molten resin packed in a cavity, after the central opening of 12 of a disk substrate 7 being formed, a movable mold 14 is opened, separated from a fixed mold, and stopped. A tripper 13 is brought near the disk substrate 7 surface of the movable mold 14, and a rubber pad 9 is attracted near the inner fringe part of the disk substrate 7, a sprue 8 is held by a sprue chuck 11. The ejector pin 5 is advanced, the sprue 8 is demolded, an ejector sleeve 3 is also advanced during the advance of the ejector pin 5, the advance distance of the ejector sleeve 3 is absorbed by the bellows-shaped extention/contraction part of the rubber pad 9. When the disk substrate is absent, the end surface of the ejector sleeve 3 contacts the rubber pad 9 to prevent curling in demolding.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ejection mechanism for ejecting a disk substrate such as a CD or a DVD from a mold after molding the disk substrate so as not to warp.

[0002]

2. Description of the Related Art Conventionally, when removing the disk substrate from a mold cavity, a rubber pad, which is a holding portion of an unloader, is sucked and held by a vacuum pressure on an inner peripheral portion of the disk substrate, and then the disk substrate is installed in a mold. The ejector sleeve thus protruded and advanced to release the disk substrate from the mold, and was conveyed to the next step by the unloader.

[0003]

In the above prior art, the position of the rubber pad on the disk substrate is
In order to securely hold the disk substrate after the suction, the disk substrate is provided as close as possible to the outer peripheral side of the disk substrate, near the inner peripheral side boundary of the signal area. On the other hand, the ejector sleeve is provided inside the stamper holder, and can be provided only at the innermost peripheral edge of the disk substrate. Therefore, the axis of the ejector sleeve does not coincide with the axis of the rubber pad, and the state shown in FIG. 4 is obtained when the disc substrate is projected. Since the position of the rubber pad holding the disk substrate is on the outer peripheral side of the outer diameter of the ejector sleeve, As the disk advances, the inner peripheral portion of the disk substrate is deformed outward by a couple. This deformation is remarkable in a DVD disk substrate to which a thin substrate having a thickness of 0.6 mm is bonded, and becomes a major obstacle in bonding.

[0004]

Therefore, the end surface of the ejector sleeve for releasing the molded disk substrate from the mold is provided when the holding portion of the unloader for holding and transferring the disk substrate and the disk substrate are not present. It was configured so as to abut, thereby preventing the occurrence of a couple.

[0005]

Embodiments of the present invention will be described in detail with reference to the drawings. The drawing is a schematic view showing a central portion of a movable mold 14 in a disk substrate molding mold.
FIG. 1 shows a central part of a movable mold 14 separated from a fixed mold (not shown) after the male cutter 4 advances to form a center opening 12 of the disk substrate 7. FIG. 2 shows that the unloader 13 is close to the movable mold shown in FIG.
This shows a state in which the elastic rubber pad 9 provided at the tip of the disk substrate 7 is attracted to the vicinity of the inner peripheral edge of the disk substrate 7 by vacuum pressure. The unloader 13 also has a sprue chuck 11 for holding the sprue 8 and carrying it out of the movable mold 14 together with the disk 7.

The movable mold 14 includes a mirror plate 1 on which the stamper 6 is placed, a stamper holder 2 which is inserted into a center opening of the mirror plate 1 to hold an inner peripheral end of the stamper 6, and a stamper holder 2. An ejector sleeve 3 slidably fitted into the coaxial inner hole 2, a male cutter 4 slidably fitted into the coaxial inner hole of the ejector sleeve 3, and a slidable member into the coaxial inner hole of the male cutter 4. It consists of a protruding pin 5 fitted and
The outer peripheral edge of the stamper 6 is held by a pressing ring (not shown). The ejector sleeve 3, the male cutter 4, and the protruding pin 5 are respectively moved back and forth by a drive unit such as a hydraulic cylinder.

The unloader 13 is driven by a pneumatic cylinder, an electric motor, or the like. When the movable mold 14 is separated from the fixed mold, the unloader 13 enters the gap to hold and transport the disk substrate 7 and the sprue 8. And the sprue chuck 11. The arms 10 are erected at a plurality of equal intervals on the same circumference, are provided with rubber pads 9 having bellows-like elastic portions at their ends, and constitute a holding portion for sucking the disk substrate 7 by vacuum pressure. . The rubber pad 9 is attached to the arm 1
The vacuum pressure can be obtained at a predetermined time by communicating with a vacuum source via an electromagnetic valve (not shown) through an internal space pipe of 0 or a separately provided hose or the like. The sprue chuck 11 is a scissor-shaped member that operates by pneumatic or electromagnetic force.
At a predetermined time, the sprue 8 is held and opened.

The operation will be described. At an appropriate time when the molten resin filled in the cavity formed by the fixed mold and the movable mold 14 (not shown) is being cooled and solidified, the male cutter 4 is moved forward together with the protruding pin 5 and the center opening of the disk substrate 7 is opened. 12 is formed. Then movable mold 1
4 is opened, stopped at a predetermined distance from the fixed mold (FIG. 1). The unloader 13 approaches the surface of the disk substrate 7 of the movable mold 14, the rubber pad 9 is attracted to the vicinity of the inner peripheral edge of the disk substrate 7, and the sprue chuck 11 holds the sprue 8. Next, the protruding pin 5 further advances to release the sprue 8. Then, the ejector sleeve 3 also starts to advance forward in synchronization with the push-out pin 5 (FIGS. 2 and 3). At this time, the ejector sleeve 3
The forward moving distance is absorbed by the bellows-like elastic portion of the rubber pad 9.

As described above, when the disk substrate 7 protrudes, the end surface of the ejector sleeve 3 pushes around the inner peripheral edge of the disk substrate 7, so that the end surface of the ejector sleeve 3 does not coincide with the axis of the rubber pad 9 as shown in FIG. In the case of a conventional take-out mechanism, the inner side of the rubber pad 9 of the disk substrate 7 warps outward due to the couple. As shown in FIG. 3, the take-out mechanism of the present invention is configured such that at least a part of the acting force by the end face of the ejector sleeve 3 and the reaction force of the rubber pad 9 are opposed to each other in the axial direction. When the disk substrate 7 does not exist, the end face of the ejector sleeve 3 is brought into contact with the rubber pad 9.

The embodiment shown and described above relates to the embodiment in which the stamper 6 is provided on the movable mold 14.
The stamper may be provided in a fixed mold. Even in that case, the present invention can be similarly applied since the protrusion and removal of the disk substrate 7 are performed by the movable mold.

[0011]

Since the mechanism for taking out the disk substrate is constructed as described above, it is possible to prevent the warpage that occurs when the disk substrate is released by advancing the ejector sleeve. An excellent disk substrate satisfying the required standard can be obtained.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing a movable mold 14 separated from a fixed mold (not shown) after a male cutter 4 advances to form a center opening 12 of a disk substrate 7;

FIG. 2 is a partial cross-sectional view showing a situation in which an unloader 13 is in proximity to a movable mold in FIG.

FIG. 3 is a partial cross-sectional view showing a state in which the ejection pin 5 and the ejector sleeve 3 are advanced to separate the sprue 8 and the disk substrate 7 in FIG.

FIG. 4 is a partial cross-sectional view showing a situation corresponding to FIG. 3 in a conventional take-out mechanism.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 mirror surface plate 2 stamper holder 3 ejector sleeve 4 oscutter 5 protruding pin 6 stamper 7 disk substrate 8 sprue 9 rubber pad 10 arm 11 sprue chuck 12 center opening 13 unloader 14 movable mold

Claims (1)

[Claims] 1. An end surface of an ejector sleeve for releasing a molded disk substrate from a mold is brought into contact with a holding portion of an unloader for holding and transferring the disk substrate when the disk substrate does not exist. A disk substrate unloading mechanism.