JPH0688293B2 - Information recording disk injection molding apparatus and mirror surface plate centering method thereof - Google Patents

Description

TECHNICAL FIELD The present invention relates to an information recording disk injection molding apparatus.

BACKGROUND ART Most transparent substrates of information recording disks such as optical disks are formed by injection molding equipment using PC (polycarbonate) or PMMA (polymethylmethacrylate) as a material.

The injection molding apparatus has a pair of mold bodies each having a mold molding surface and forming a mold space by being clamped to each other, and an injection unit for injecting a molten material to be molded into the mold space. ing. FIG. 4 shows the mold of the conventional device.

As shown in FIG. 4, the mold body is a rectangular plate-shaped mold plate 1 and a disk-shaped mold that is fixed to the main surface of the mold plate 1 with a plurality of bolts 2 to form one surface of a disk substrate to be molded. Mirror plate 3
And a mounting plate 4 in the form of a rectangular plate, which is joined to the template 1 so as to overlap with each other by bolts (not shown) and is fitted onto the mirror plate 3 to prevent the mirror plate from being displaced in the radial direction.

When assembling the template having the above-described structure, first, the mounting template 4 is overlaid on the template 1 and fastened with bolts (not shown). Then, the circular recess 4a formed in the mounting template 4
The mirror plate 3 is inserted therein and fixed to the template 1 with the bolt 2.

In the mold having the above structure, the diameter of the circular recess 4a into which the mirror plate 3 is inserted is slightly larger than the diameter of the mirror plate 3,
A gap is created between the inner peripheral surface of the circular recess 4a and the outer peripheral surface of the mirror plate 3. Therefore, the center of the mirror plate 3 can be deviated from the center of the circular recess 4a within the range of this gap, and it is not always easy to center the mirror plate 3 with high precision with respect to the circular recess 4a.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object thereof is an information recording disk injection molding apparatus capable of easily and accurately centering a mirror surface plate with respect to a template. And a method for centering a mirror plate.

An information recording disk injection molding apparatus according to the present invention comprises a template having a circular concave portion for accommodating a disk-shaped mirror surface plate on a main surface, and sandwiching the circular concave portion in two substantially perpendicular diameter directions of the circular concave portion. A mirror plate centering mechanism including a pair of contact members movably provided in each of the diametrical directions and contacting the outer periphery of the mirror plate, and position adjusting means for adjusting the position of each contact member. Is characterized by.

Further, in the mirror surface plate centering method of the information recording disk injection molding apparatus according to the present invention, the step of adjusting the position of the contact member by the position adjusting means, the inner peripheral surface of the circular recess and the outer peripheral surface of the mirror surface plate are performed. The process of inserting the foil member into the gap of
The step of fixing the mirror plate to the template by the fixing means.

Embodiments Hereinafter, an information recording disk injection molding apparatus and a method of centering a mirror surface plate thereof as an embodiment of the present invention will be described with reference to the accompanying drawings.

As shown in FIG. 1, in an information recording disk injection molding apparatus as an embodiment of the present invention, a fixed mold body 11 having a molding surface and fixed on a base (not shown), and a fixed mold body 11 on the base. It has a fixed mold body 11 and a movable mold body 12 that is provided so that the mold molding surfaces face each other and is movable in the direction of arrow S, which is a direction perpendicular to the mold molding surfaces. In addition,
Although not shown, a hydraulic cylinder is provided as a mold clamping means for moving the movable mold body 12 and clamping the fixed mold body 11 and the movable mold body 12 together.

The fixed mold body 11 includes a fixed mold plate 13, a disk-shaped fixed mirror surface plate 14 that is fastened to the main surface of the fixed mold plate 13 by a bolt 14a to form one surface of a disk substrate to be molded, and the fixed mold plate. 13
And an annular fixed mounting template 15 that is coupled to the fixed mirror surface plate 14 to prevent the fixed mirror surface plate 14 from shifting in the radial direction. A hollow cooling sleeve 16 is inserted so as to penetrate through the centers of the fixed mold plate 13 and the fixed mirror plate 14, and a cylindrical spool 17 is inserted in the cooling sleeve.
Is provided. The spool 17 is a PMMA in a molten state, which is injected by a nozzle 18 by an injection means (not shown in its entirety).
A molding material such as (polymethylmethacrylate) is guided into a mold space 19 defined by the fixed mold body 11 and the movable mold body 12.

On the other hand, the movable mold body 2 includes movable mold plates 23 and 24 which are fastened to each other by bolts (not shown) or the like, and an inner movable mold plate 23.
It is composed of a disk-shaped movable mirror surface plate 25 fastened to the main surface by a bolt 25a, and an annular movable mounting template plate 26 that is coupled to the movable template plate 23 to prevent the movable mirror surface plate 25 from shifting in the radial direction. As shown in FIG. 2, a stamper 28 that forms the other surface of the substrate to be molded is provided on the main surface of the movable mirror surface plate 25. The stamper 28 is not shown in FIG. The stamper 28 is for forming signal recording pits on the substrate to be molded, and is formed in a thin plate shape and in an annular shape.

In addition, a water channel is provided on each rear surface of the fixed mirror plate 14 and the movable mirror plate 25.
14b and 25b are formed, and the solidification of the material to be molded is promoted by the cooling water supplied into the channel by the water supply means (not shown).

The inner peripheral portion and the outer peripheral portion of the movable mirror surface plate 25, which are formed in a disk shape, are cylindrical inner circumferences for pressing and fixing the inner peripheral portion and the outer peripheral portion of the stamper 28 to the movable mirror surface plate 25, respectively. A clamp 29 and a ring-shaped outer peripheral clamp 30 are provided respectively. The outer peripheral clamp 30 has a molding surface that defines the outer peripheral surface of the substrate to be molded, and is fastened to the movable mirror surface plate 25 with bolts (not shown). Further, the inner peripheral clamp 29 has an annular protrusion 29a protruding into the mold space 19,
The inner peripheral portion of the stamper 28 is pressed against the movable mirror plate 25 by the protrusion. The inner peripheral clamp 29 is locked to the movable mold body 12 by the locking pin 32 at the clamp position, that is, the position where the stamper 28 is pressed.

Inside the cylindrical inner peripheral clamp 29, a tubular punch 34 is provided so as to be movable in an arrow S direction which is a direction perpendicular to each mold forming surface of the fixed mold body 11 and the movable mold body 12.
The tip of the punch 34 forms a part of the molding surface, in this case, a portion corresponding to the center hole of the substrate formed by cooling and solidifying the material to be molded. The punch 34 is connected to the output shaft of a hydraulic cylinder (not shown) and driven in the direction of the arrow S, and cooperates with a die 35 provided on the fixed mold body 11 side to punch a central hole of a substrate to be molded. The cooling sleeve 16 and the spool 17 arranged in the die 35 are retracted in accordance with this punching operation.

Inside the punch 34, an eject pin 36 for reciprocating in the direction of arrow S is provided for removing the portion corresponding to the center hole of the substrate, which is punched by the punch 34 and attached to the punch, from the punch 34. This eject pin
36 is also driven by a hydraulic cylinder (not shown).

A cylindrical ejector 37 and a stationary sleeve 38 are concentrically provided between the inner peripheral clamp 29 and the punch 34. The ejector 37 is for ejecting the molded substrate to separate it from the stamper 28, is movable in the direction of arrow S, and is also driven by a hydraulic cylinder (not shown). The fixed sleeve 38 is fixed to the movable mold body 12 with bolts or the like, and guides the movement of the ejector 37. Air blow grooves 37a and 38a are formed on the outer peripheral surfaces of the ejector 37 and the fixed sleeve 38, respectively. Pressurized gas is supplied to each of the air blow grooves 37a and 38a from a gas supply pump (not shown), and the pressurized gas is supplied to the inner peripheral clamp 29-fixing sleeve 38 when the molded substrate is released from the mold.
Between the ejector 37 and the fixed sleeve 38, and the molded substrate is extruded and separated from the stamper 28.

As shown in FIG. 3, a fixed mounting template 15 having a circular recess 15a for accommodating a disk-shaped fixed mirror plate 14 is provided with the circular recess 15a and two diametrical directions D _{1 of the} circular recesses perpendicular to each other. A pair of screw holes 15b and 15c are formed so as to be sandwiched at D ₂ and extend in the respective diametrical directions. Cylindrical abutting members 39 and 40 are slidably inserted into the screw holes 15b and 15c, respectively. Each of the screw holes 15b and 15c communicates with the circular recess 15a, so that each of the contact members can contact the outer peripheral surface of the fixed mirror surface plate 14 at one end. Adjustment screws 41 and 42 are screwed into the screw holes 15b and 15c, respectively, and the tips of the adjustment screws can contact the other ends of the contact members 39 and 40, respectively. The position of each contact member 39 and 40 is adjusted by operating each of these adjusting screws as described later, and the fixed mirror plate for the fixed mold plate 11 and the fixed mounting mold plate 15 is adjusted.
14 are centered.

In addition, as shown in FIG. 1, the movable mirror surface plate 25 is provided with a circular concave portion.
The movable mounting template 26 housed in 26a also has a fixed mounting template 15
Similarly, each pair of screw holes 26b and 26c
26a is defined by two diametrical directions D ₁ and D perpendicular to each other in the circular recess
₂ (illustrated in FIG. 3) so as to be sandwiched and extend in the respective diametrical directions. These screw holes 26b and 2
Cylindrical abutting members 43 and 44 are also slidably inserted in the inside of 6c, and one end of each abutting member has a movable mirror surface plate 25.
It is possible to contact the outer peripheral surface of the. Each screw hole 26b and 26c
The adjusting screws 45 and 46 are screwed into the end of the movable member so as to contact the other ends of the contact members 43 and 44, and the movable mold plate 23 and the movable mounting die are operated by operating these adjusting screws. The movable mirror plate 25 is centered on the plate 26.

Next, the operation of the information recording disk injection molding apparatus having the above configuration will be briefly described.

First, the movable mold body 12 is pressed against the fixed mold body 11 by a hydraulic cylinder (not shown) to perform mold clamping, and a mold space 19 is formed. Then, the material to be molded in a molten state is injected from the nozzle 18, and this is molded by the spool 17
You will be guided to 19. The molding material filled in the mold space 19 is solidified by cooling to form a substrate. After this,
During the piercing process, the punch 34 projects and at the same time the cooling sleeve 16 and the spool 17 retract together with the center of the substrate to be punched. A central hole is thus formed in the substrate.

After that, the fixed mold body 11 is formed together with the substrate on which the movable mold body 12 is formed.
At the same time, the eject pin 36 protrudes, and at the same time, the center portion of the substrate, which has already been punched and attached to the tip of the punch 34, is separated from the punch 34. Then, as a releasing process, a pressurized gas, in this case pressurized air, is supplied to each of the air blow grooves 37a and 38a, whereby the substrate slightly floats from the stamper 28 on the movable mirror surface plate 25. After this, the ejector 37 projects and the substrate is peeled off from the stamper 28 and collected.

Next, the assembling work of the fixed mold body 11 of the above-mentioned information recording disk injection molding apparatus will be described. The movable body 12
Since the assembling work of is almost the same as the assembling work of the fixed mold body 11, detailed description thereof will be omitted.

As shown in FIG. 3, the fixed mold plate 13 is attached to a workbench (not shown).
It is installed so that its main surface is horizontal, a fixed mounting template 15 is overlaid on the stationary template, and both are fastened with bolts (not shown). Then, the fixed mirror plate 14 is inserted into the circular recess 15a formed in the fixed mounting template 15. Fixed mirror plate 14
After being accommodated in the circular recess 15a, the adjustment screws 41 and 42 are appropriately operated to adjust the positions of the contact members 39 and 40, and the center of the fixed mirror plate 14 is aligned with the center of the circular recess 15a. To do. Since each abutting member 39 and 40 is fitted and inserted into the screw holes 15b and 15c, respectively, it can be moved only in the direction to be adjusted, and therefore, it is added to the adjusting screws 41 and 42 by an adjusting tool such as a screwdriver. The force in the rotating direction is not transmitted to the fixed mirror plate 14, and only the force in the direction to be adjusted is applied to the fixed mirror plate 14.

Circular recess 15a of the fixed mirror plate 14 by the adjusting screws 41 and 42
After the centering is completed, a small piece of foil member 48 made of titanium or the like is appropriately inserted into a space between the outer peripheral surface of the fixed mirror plate 14 and the inner peripheral surface of the circular recess 15a at a position where this can be inserted. As a result, the fixed mirror plate 14 is fixed to the fixed mounting plate 15.
Also, it is firmly fixed to the fixed mold plate 13 and is prevented from being displaced in the radial direction. The foil member 48 is prepared with various thickness dimensions such as 10 μ / m, 15 μ / m or 20 μ / m, and these are appropriately selected according to the size of the gap between the fixed mirror plate 14 and the circular recess 15a. Select and use.

After inserting the foil member 48, the bolt 14
By tightening a, the fixed mirror plate 14 is firmly fixed to the fixed mold plate 13 and the fixed mounting mold plate 15. The foil member 48 may be pulled out after this to collect it, or may be left inserted.

In this way, after the centering by the adjusting screws 41 and 42 is completed, the fixed mirror surface plate 14 is fixed by the bolt 14a after inserting the foil member 48 to prevent the fixed mirror surface plate 14 from shifting.
When the bolt 14a is tightened, the fixed mirror surface plate 14 does not shift even if slightly.

As described above in detail, in the information recording disk injection molding apparatus according to the present invention, the circular concave portion is substantially perpendicular to the circular concave portion on the template having the circular concave portion for accommodating the disk-shaped mirror surface plate on the main surface. A pair of abutting members provided so as to be sandwiched in two diametrical directions and movably in each diametrical direction and abutting on the outer periphery of the mirror plate, and position adjusting means for adjusting the position of each of the corresponding abutting members. It has a mirror plate centering mechanism.

Since the mirror plate centering mechanism is provided as described above, the mirror plate can be centered with respect to the template easily and with high accuracy. Further, since the contact member movable only in the direction to be adjusted is interposed between the position adjusting unit and the mirror surface plate to be centered by the position adjusting unit, the position adjusting unit is, for example, an adjusting screw. In this case, the force in the rotation direction applied to the adjusting screw by a driver or the like is not transmitted to the mirror surface plate, and only the force in the direction to be adjusted is applied to the mirror surface plate. Therefore, the mirror surface plate moves only in the direction to be adjusted, and does not move in the other directions at all, so that the centering can be performed extremely accurately and easily.

In the method of centering the mirror surface plate of the information recording disk injection molding apparatus according to the present invention, the step of centering the mirror surface plate with respect to the template by adjusting the position of the contact member by the position adjusting means, A process of inserting a foil member into the gap between the inner peripheral surface of the circular recess and the outer peripheral surface of the mirror plate to prevent radial displacement of the mirror plate with respect to the template, and firmly fixing the mirror plate to the template by fixing means. And the process of doing.

When the fixing means is, for example, a bolt, the mirror-finished plate, which has already been centered once by the position adjusting means, is slightly displaced each time the bolt is tightened, and the position adjusting work and the bolt tightening are performed. There is a possibility that the work and the alternating work may have to be repeated many times. As described above, in the mirror surface plate centering method according to the present invention, after the centering by the position adjusting means is completed, a foil member is fitted between the mirror surface plate and the circular recess to prevent the mirror surface from being displaced, and then the mirror is fixed by the fixing means. Since the face plate is fixed, the position adjusting operation by the position adjusting means and the fixing operation by the fixing means only have to be performed once, and the centering of the mirror surface plate can be performed quickly.

[Brief description of drawings]

FIG. 1 is a side view including a partial cross section of an information recording disk injection molding apparatus as an embodiment of the present invention, and FIGS. 2 and 3 are main parts of the information recording disk injection molding apparatus shown in FIG. FIG. 4 is an enlarged cross-sectional view and a diffusion exploded view, and FIG. 4 is a diffusion exploded view of a main part of a conventional information recording disk injection molding apparatus. Description of symbols for main parts 13 …… Fixed template 14 …… Fixed mirror plate 15 …… Fixed mounting template 23,24 …… Movable template 25 …… Movable mirror plate 26 …… Movable mounting template 28 …… Stamper 39,40,43,44 …… Abutting member 41,42,45,46 …… Adjusting screw 48 …… Foil member

Claims (3)

[Claims] 1. A mold forming surface is formed, and said mold forming surfaces are arranged so as to face each other, move relative to each other in a direction substantially perpendicular to said mold forming surface, and form a mold space by said mold forming surface. A pair of mold bodies, a mold clamping means for clamping the mold body, and an injection means for injecting a molten material to be molded into the mold space after the mold is clamped, the mold body having a circular shape on its main surface. An information recording disk injection molding apparatus comprising: a mold plate having a recess formed therein, a mirror surface plate fitted in the circular recess, and fixing means for fixing the mirror surface plate to the mold plate,
A pair of abutting members provided on the template so as to sandwich the circular recess in two diametrical directions substantially perpendicular to each other and movably in each of the diametrical directions so as to abut the outer circumference of the mirror plate. An information recording disk injection molding apparatus having a mirror surface plate centering mechanism comprising a member and position adjusting means for adjusting the position of each of the abutting members. 2. The information recording disk injection molding apparatus according to claim 1, wherein the position adjusting means is an adjusting screw which is screwed into the template and slidably contacts the abutting member at a tip portion thereof. 3. A step of adjusting the position of the contact member by the position adjusting means, and a step of inserting a foil member into a gap between the inner peripheral wall surface of the circular recess and the outer peripheral surface of the mirror plate.
3. The method of centering a mirror plate in an information recording disk injection molding apparatus according to claim 1, comprising a step of fixing the mirror plate to the template by the fixing means.