JPH03100940A - Method and jig for aligning core of optical disk - Google Patents

Abstract

PURPOSE:To suppress the accuracy of core deviation within a prescribed range by inserting divided cylindrical pins, which are divided into two, into the central holes of two optical disks, moving the disks in the reverse direction to an axial direction and changing the diameter of a circumscribed circle composed of the two-divided cylindrical pins. CONSTITUTION:Since one divided cylindrical pin 31 is equipped with an inclined surface 1 to the axial direction, the falling pressure of a pressing pin 51 not only lowers the pin 31 against a cylindrical pin return spring 44 but also presses the side of another divided cylindrical pin 32. However, since the pin 32 is restricted by a divided ring 41, with the fall of the pin 31, a divided ring 42 supporting the pin 31 is moved in a side surface direction. With the fall of the pin 31, at first, the outer peripheral circle of the pin 31 brought into contact with central holes 14 and 24 of a center hub and further, disk substrates 11 and 21 are horizontally moved in the same direction. When a circumscribed circle 2 formed by the both semi circles of the pins 31 and 32 is equal with the central holes 14 and 24, the amount of the core deviation is within the tolerance of the both center hubs and the cores of the substrates 21 and 11 are aligned.

Description

Detailed Description of the Invention (a) Field of Industrial Application The present invention relates to an alignment method and an alignment method used for bonding optical discs using uneven pits formed from transparent synthetic resin plates as signal recording media. This relates to a matching jig.

(B) Prior Art The misalignment accuracy of the bonding of two optical disc substrates must be kept within the so-called tracking accuracy, which is the position control of the head of a device that reads signals recorded on the optical disc.

For example, 1K Publication No. 1983-71956 and Utility Model Publication No. 1987-71956
Japanese Patent No. 26628 discloses an apparatus for bonding both substrates together by limiting their outer diameters using a plurality of positioning claws or the like. Since the board is a resin molded product using an injection molding machine,
The larger the outer diameter, the greater the deformation of the substrate. For this reason, centering work based on outer diameter reference alignment became difficult, and bonding within the required accuracy was almost impossible.

Therefore, the bonding method based on the inner diameter using the center hole provided in the substrate has been conventionally used.
The method disclosed in Japanese Patent No.-247934 corresponds to this.

(C) Problems to be Solved by the Invention However, these methods require the diameter of the center hole to be a certain size. The diameter of the center hole is 4mm.
This method cannot be applied when bonding two optical disk substrates to which a center hub is pre-attached.

In other words, the center hub could only be attached after the two boards were pasted together. Bonding the boards! i
When attaching the center hub to the board, it is necessary to read the traces transferred to the board during molding and find the center position of the groove. Conventionally, it was not possible to remove the center hub with high accuracy.

The present invention provides an optical disk that can suppress the misalignment accuracy of the bonded ribs of both optical disk substrates to within the tracking accuracy of an optical disk signal reading device, regardless of whether or not a center hub is attached to the substrate in advance. The object of the present invention is to provide an alignment method and an alignment jig.

(D) Means for Solving 1JAH The present invention is a center that takes advantage of the fact that the diameter of the circumscribed circle formed when a rod-shaped pin is divided diagonally into two and moved forward and backward along an inclined surface increases and decreases. The above problem is solved by aligning and bonding two disk substrates together using a matching jig. That is, the optical disc centering method of the present invention involves aligning two optical discs having center holes (14 and 24).
11 and 21), which uses split cylindrical pins (31 and 32) that have a diameter slightly smaller than the diameter of the center hole and are divided into two by a plane that is inclined with respect to the axis. By inserting the two optical discs into the center holes and moving them in opposite directions in the axial direction, alignment is achieved by changing the diameter of the circumscribed circle (2) formed by the two split cylindrical pins. In addition, in the centering jig of the present invention, the upper die jig is provided with a retaining pin (51) attached with a retaining ring (52) for preventing removal, and the lower die jig is provided with a retaining pin (51) attached to the axial center. A cylindrical pin (31
and 32), a split ring (41) that is divided into two along a plane parallel to the axis, holds a split cylindrical pin on its inner circumferential surface, and is prevented from disassembling by the contractile force of a retaining spring (43) provided on its outer circumference. and 42), and a cylindrical pin return spring (44) which functions to restore the relative axial movement of the divided cylindrical pins.

Note that the symbols in parentheses indicate corresponding members in the embodiments described later.

(E) 1% The method for aligning an optical disk according to the present invention and the alignment of the optical disk using the alignment jig are performed as follows. First, two optical disk substrates (+11 and 21) are held by an upper mold jig (61) and a lower mold jig (62), respectively, and overlapped.

At this time, there is a slight gap (3) between both disk boards.
is provided, and both disk substrates are in a state in which horizontal movement is possible to correct misalignment. When bonding one disk substrate together and applying pressure, first the lower surface of the press plate (63)
hits the head of the presser pin (51) attached to the upper die jig, and the pressure is further transmitted to the tip of one of the split cylinder pins (31), so as the lower surface of the press plate descends, one of the split cylinders The pin (31) also descends. ffl!
The vertical movement of one split cylindrical pin (32) is restricted by a split ring (41). Therefore, since the - side divided cylindrical pin (31) descends along the slope (1), it also moves in the horizontal direction, and the circumscribed circle formed by the outer semicircle of each divided cylindrical pin The diameter of (2) increases as the relative movement of the split cylindrical pin in the axial direction increases.

Its outer diameter becomes larger and eventually the center hub (12 and 2
It expands until it becomes equal to the diameter of the center hole in 2).

At this time, the center holes of both disk boards (correctly, the center holes of the center hub attached to the board, 14 and 24)
) is in contact with the outer circumferential circle of the split cylindrical pin, so both disk substrates are caused to move relatively horizontally, and when the diameter of the circumscribed circle becomes equal to the center hole diameter of the center hub, both disk substrates are misaligned. This means that they are facing each other in a state where there is no such thing at all.

In this state, if the pressing force on the lower surface of the press plate is adjusted so that both disk substrates are brought into close contact and pressurized, it is possible to bond the optical disks together without misalignment.

(F) Embodiment FIG. 1 shows an optical disk manufacturing apparatus using the alignment jig according to the present invention. Two disk substrates 11 and 21 are placed with their recording layer-formed surfaces facing each other, and are placed in an upper mold jig. Tool 61
A gap 3 is provided in the lower die jig 62, and the center hubs 12 and 22 are shown in a state where they have already been accommodated in their respective boards, and are not shown here. However, adhesive is applied to the recording layer side of the disk substrates 11 and 21, and the lower surface 63 of the press plate is coated with adhesive.
pressurizes the lower die jig 61 to bond both disk substrates together. A split cylindrical pin 31 passes through the center hole 14.24 provided in both center hubs 12.22, has an outer diameter slightly smaller than the center hole diameter, and is divided into two by a plane inclined with respect to the axial direction. and 32 are provided. The tip of the circular bottle 32 is partially cut out,
1*In response to the pressure lowering of the presser pin 51 described above, the cylindrical bottle 3
Only 1 receives pressure, and its downward movement can be performed against the cylindrical bottle return spring 44.

The split rings 41 and 42 are divided into two on the axial plane, constantly receive centripetal force due to the contraction force of the holding spring 43, and support the split cylindrical pins 31 and 32 on their inner surfaces. Further, the flange portion of one split ring 41 is fixed to a lower die jig 62, and the other split cylindrical tongue 32 is fixed to the bottom surface and upper end surface of the ring. Further, one of the split rings 41 is provided with a guide pin 45, which serves as a guide for the horizontal movement of the other split ring 42. Upper mold jig 61
A retaining ring 52 is attached to the lower end of the presser pin 5, which is movable up and down by receiving pressure from the lower surface 63 of the press plate.
1 is provided.

Next, the operation of this embodiment will be explained.

First, the lower surface 63 of the press plate descends and pressurizes the head of the presser pin 51. The presser pin 51 moves downward under pressure from the press plate, and presses down one of the divided cylindrical pins 31. Since one of the split cylindrical pins 31 has an inclined surface 1 with respect to the axial direction, the downward pressure of the presser pin 51 can be applied simply by lowering the one split cylindrical pin 31 against the cylindrical bottle return spring 44. In addition, lateral pressure is also generated that tries to push the other split cylindrical pin 32 outward in the lateral direction. However, since the other split cylindrical pin 32 is restrained by one of the split rings 41 fixed to the lower mold jig 62, the lowering of the one split cylindrical pin 31 causes the one split cylindrical pin 31 to fall on the inner side surface. The other supporting split ring 42 is moved laterally. Fl! ! One split ring 42 moves horizontally along a guide pin 45 fixed to one split ring 41 against a holding spring 43 that binds the split rings 41 and 42 with centripetal force. That is, the pressure applied by the press plate moves one split cylindrical pin 31 in the lateral direction while pushing it down, and moves the other split ring 42 in the lateral direction.

By lowering one of the split cylindrical pins 31, the pin 31
The outer circumference of the disk substrate 1 first comes into contact with the center holes 14 and 24 of the center hub and continues to descend.
0-divided cylindrical beam that horizontally moves 1 and 21 in the same direction〉3
When the circumscribed circle 2 formed by both semicircles 1 and 32 becomes equal to the center hub center hole 14 or 24, the centering of both disk substrates 11 and 21 is carried out with the amount of misalignment within the tolerance of both center hubs. It means that you have done it.

At this point, the lower surface 63 of the press plate presses down the upper die jig 61, eliminates the gap 3, and both disk substrates 11 and 2
By setting 1 so as to apply pressure in close contact with each other, it is possible to manufacture an optical disk in which bonding is performed without misalignment.

Note that the above description of the embodiment refers only to the case where the center hub 12.22 is attached to the disk substrate 11.21 in advance; center hole diameter 1
If the dimensions are set to be slightly smaller than 3, it is possible to manufacture an optical disk with misalignment accuracy kept below a predetermined accuracy even when disk substrates to which the center hubs 12 and 22 are not attached in advance are bonded together. One thing is clear.

(G) As described in detail, according to the optical disc centering method and centering jig according to the present invention, the center hub can be used regardless of whether or not the center hub is pre-drilled by 1 inch on the disc substrate. , it is possible to suppress misalignment accuracy during bonding to within a predetermined accuracy.

[Brief Description of the Drawings] Fig. 1 is a sectional view showing an optical disk manufacturing apparatus using the alignment jig according to the first invention, Fig. 2 is a sectional view taken along line A-A in Fig. 1, and Fig. The figure shows the situation of the center hub center hole with respect to the downward movement of the split cylindrical pin (B-B in Figure 1).
(a cross-sectional view taken along the line). 1...Slanted surface, 2...Circumcircle, 3...Gap, 1
1.21...Disk board, 12.22-Center hub, 13.23...Disk board center hole, 14.24
...Center hub center hole, 11.31.32...Divided cylindrical bin, 11°41.42...Divided ring, 43
...Holding spring, 44...Split cylindrical bottle return spring, 45...Guide pin, 51...Press pin. 52... Retaining ring for preventing removal, 61... Upper die jig, 6
2... Lower mold jig, 63... Lower surface of press plate

Claims (1)

[Claims] 1. A method for aligning two optical disk substrates each having a center hole, the substrates having a diameter slightly smaller than the diameter of the center hole, and dividing into two by a plane that is inclined with respect to the axis. By inserting the divided cylindrical pins into the center holes of the two optical discs and moving them in opposite directions relative to each other in the axial direction,
An optical disc centering method that performs centering by changing the diameter of a circumscribed circle formed by two split cylindrical pins. 2. A split cylindrical pin that has a diameter slightly smaller than the center hole diameter of the optical disc to be aligned and is divided by a plane that is inclined to the axis, and a cylinder that is divided by a plane that includes the axis and is divided by an inner cylindrical surface. A split ring that supports the pin, a retaining spring that is provided on the outer periphery of the split ring and holds the split ring together by its contractile force, and a retaining spring that is provided between the split ring and the split cylindrical pin. An optical disc centering jig comprising a cylindrical pin return spring acting to restore relative axial movement of split cylindrical pins.