JPH0449543A - Hub joining device for optical information recording medium - Google Patents

Abstract

PURPOSE:To center a hub to the center of turning of a group of disk substrates with a high precision to easily and stably join the hub in a short time by providing a disk eccentricity correcting means which can be moved in horizontal and vertical directions, a means which detects the group or an area boundary, etc. CONSTITUTION:The outer peripheral end of a substrate 10 is brought into contact with members 210a and 210b by pressing plates 212 and 213, and the substrate 10 is sucked and fixed to a face 103 by suction from a vacuum groove 107, and a hub 20 is placed on the substrate 10. Boundary positions in four directions are obtained by a group area detecting means 300. A Z table 202 is set to the 'equal' position by a fine adjustment mechanism 201, and the substrate 10 is fixed to a placing part 206 of a Y table 205 by a suction from a groove 207. The Z table 202 is set to the 'high' position, and the eccentricity of an X table 204 is eliminated by a mechanism 203. Next, the table 202 is set to the 'equal' position and the substrate 10 is sucked to the face 103. The outer peripheral end of the substrate 10 is pressed, and the hub 20 is joined to the disk substrate 10 with an ultrasonic means 400 by welding. In this case, a projecting part 22 is fused and disappears to firmly join them.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of the Invention] The present invention relates to a hub joining device for optical information recording media. The present invention relates to an apparatus for joining a hub of an optical information recording medium, which is used to join a hub to a disk substrate of an optical information recording medium in a highly accurate manner.

[Technical Background of the Invention] In recent years, optical information recording media that use high energy density beams such as laser beams have been developed and put into practical use. This optical information recording medium is called an optical disk and can be used as a video disk, an audio disk, a large-capacity still image file, and a large-capacity computer disk memory.

The basic structure of an optical disk is a disk-shaped transparent resin substrate made of plastic, glass, or the like, and a recording layer provided on this substrate. The surface of the substrate on which the recording layer is provided is coated with an undercoat layer or an intermediate layer made of a polymer material in order to improve the flatness of the substrate, improve the adhesion with the recording layer, and improve the sensitivity of the optical disc. may be provided.

Currently, for optical disks with a diameter of 130 mm (5.25 inches), an optical information recording medium using a hub (magnetically sensitive hub) is defined by the ISO standard. This optical disc is an information recording disc with an air sandwich structure in which two disc-shaped resin substrates each having a circular hole in the center and a recording layer provided on at least one side are joined with the recording layer inside, Hubs are joined to both sides. The hub plays the role of a disc clamp that ensures the secure mounting and fixing of the optical disc when the optical disc is rotated by a recording/playback device, etc. It has a clamping hole in the center and is used to hold metal pieces, etc. It is equipped with a magnetically sensitive material and is fixed by magnetic force.

Therefore, when manufacturing an optical disk, the hub must be joined so that its center of rotation precisely matches the center of rotation of the group formed on the disk substrate.

The methods for joining the hub to the disk as described above can be roughly divided into (A) fitting the hub into the circular hole provided in the center of the disk substrate so that its center is concentric with the rotation center of the group; (B) X based on the group or group area boundary of the disk substrate;
There is a method of joining the hubs using a Y table so that the center of the hub matches the rotation center of the group.

In method (A) above, joining the hub itself is relatively simple, but it is important to ensure that the circular hole in the disk substrate is not eccentric to the rotation center of the group and that the diameter of the circular hole is accurate. must be manufactured. Compared to this, the above (B
) has the advantage that the hub can be joined without being affected by the eccentricity and diameter of the circular hole in the disk substrate.

Japanese Patent Laid-Open No. 63-76131 proposes a disk hub mounting device for an optical disk that utilizes the method belonging to the above (B).

However, the device described in the above publication has several problems when put into practical use. One of them is means for detecting the boundary between the region of the disk substrate where the pregroove is formed and the region where the pregroove is not formed.

That is, in the apparatus described in the above publication, the reflectance detectors 202a and 202 shown in FIG.
b, 202c, and 202d are used to detect the boundary, but in reality, the center of rotation of the pregroove must be eccentric within 10 μm. The distance from the center to each reflectance detector is the distance from the center to 202a - the distance from the center to 2025, and the distance from the center to 202a is
020-202d from the center, and each reflectance detector must be arranged so that the error thereof is highly accurate within 2 to 3 μm.

However, it is difficult to arrange each reflectance detector with such high precision and maintain it without being affected by changes in environmental conditions.

Furthermore, when using the apparatus described in the above-mentioned publication, it is extremely difficult to join the hub to the disk substrate with good precision using the ultrasonic fusion joining method. The ultrasonic fusion bonding method is excellent for mass production because the bonding between the disk substrate and the hub is completed in an instant, and maintenance of the bonding equipment is easy because no liquid adhesive is used. This is an extremely excellent method for bonding a hub to a disk substrate, as it has many advantages, such as the fact that there is no adhesive as a foreign substance on the bonding surface, so the performance of the optical disk is less affected by changes in temperature and humidity. It is. However, it is practically undesirable that the ultrasonic fusion bonding method is difficult to use when the apparatus described in the above publication is used. Incidentally, Publication No. 1-1 only describes a method of fixing the hub using an adhesive as a means for joining the hub.

The reason why it is extremely difficult to accurately join the hub to the disk substrate by the ultrasonic fusion bonding method when using the apparatus described in the above publication is as follows. That is,
The principle of ultrasonic welding is to convert ultrasonic electrical energy into mechanical vibration energy and apply pressure at the same time to generate frictional heat on the joint surface of the disk substrate and hub, melting and welding the joint surface. be. Therefore, since the horn of the ultrasonic welding machine vibrates during welding, the nodal point (the point of the smallest amplitude) of the horn is normally held elastically using an O-ring or the like.

Therefore, it is extremely difficult to join the hub temporarily fixed to the tip of such a horn in a state where it is stably and accurately centered with respect to the rotation center of the group.

In order to solve the above-mentioned problems, the present invention makes it possible to easily and stably join a hub to a disk substrate with high efficiency and with high precision centering with respect to the rotation center of the disk substrate group. He invented a hub joining device for optical information recording media, and the applicant of this patent has already filed a patent application (Japanese Patent Application No. 1-84343).

The invention according to the above patent application provides a vacuum groove on the outer circumference for adsorbing the inner circumference of the disk substrate, a hub locking protrusion for fitting the clamping hole of the hub in the center, and A disk rotating means is provided rotatably on a spindle case fixed to a base with a spindle main shaft having a mounting surface at the upper end vertically, and a vacuum groove for adsorbing the outer periphery of the disk substrate is used to rotate the disk. A horizontally and vertically movable disk eccentricity correcting means surrounding the means and having at an upper end, a means for detecting a group or group region boundary formed on the disk substrate, and a hub are joined by ultrasonic welding. An apparatus for hub joining of optical information recording media, characterized in that it comprises at least means.

Although this hub bonding device has the excellent features described above, in some cases, when bonding a hub to a disk substrate by ultrasonic welding using this device,
Ultrasonic vibrations are transmitted to the disk substrate through the hub, and the frictional force between the disk substrate and the disk substrate mounting surface of the bonding device momentarily becomes close to zero, which may cause the disk substrate to shift laterally. In that case, the eccentricity of the hub may increase and the joining accuracy of the hub may decrease.

[Object of the Invention] The present invention provides a method for bonding a disk substrate group in a state in which it is centered with respect to the center of rotation of a disk substrate group with high precision, without using a bonding device equipped with a special highly accurate group or group area detection means. The hub can be easily joined to the disk substrate with high efficiency, and when the hub and the disk substrate are ultrasonically fused, the disk substrate is prevented from shifting laterally due to ultrasonic vibration for one minute, resulting in high precision. It is an object of the present invention to provide a hub joining device for an optical information recording medium that can stably join a hub to a disk substrate while reliably maintaining a centered state.

[Summary of the Invention] The present invention has an inner annular vacuum groove on the outer circumference for adsorbing the inner circumference of the disk substrate, and a hub locking protrusion on the center for fitting the clamping hole of the hub. established,
A disk rotating means rotatably provided on a spindle case fixed to a base with a spindle main shaft having a disk substrate mounting surface at the upper end being vertical, and a disk substrate provided at a position surrounding the disk rotating means. an outer annular vacuum groove for adsorbing the outer periphery, two disk substrate stop members provided outside the outer annular vacuum groove and within the same semicircle of the outer annular vacuum groove; The disk substrate pressing member is provided on the F side at a position outside the outer annular vacuum groove and facing the two disk substrate stopping members across the hub locking protrusion, and the disk substrate pressing member is provided in the horizontal and vertical directions. An optical information recording device comprising at least a movable disk eccentricity correction means, a means for detecting a group or group area boundary formed on the disk substrate, and a means for joining hubs by ultrasonic fusion. This is a device for hub joining of media.

DETAILED DESCRIPTION OF THE INVENTION The hub joining device of the present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 is a partially cross-sectional schematic diagram showing an embodiment of the hub joining device for optical information recording media of the present invention.

In FIG. 1, the hub joining device includes a disk rotating means fixed to the base 1, a disk eccentricity correcting means fixed to the base 1, and a group arranged above the outer periphery of the disk placed on the disk rotating means. Area boundary detection means 3
00, and ultrasonic fusion bonding means 400 disposed above the central portion of the disk rotation means.

The disk rotation means has a spindle main shaft 102 rotatably arranged vertically in a spindle case 101 fixed to a base 1, and has a disk substrate mounting surface 103 on the upper surface of the spindle main shaft 102. A disk substrate mounting section 104 is provided, and the disk substrate mounting section 1
A recess 105 large enough to accommodate the hub 20 is provided in the center of the upper surface of the 04, and the hub 2 is placed in the center of the recess 105.
Hub locking protrusion 1 for fitting the clamping hole of 0
06 is provided so as to protrude from the disk substrate mounting surface 103 and be concentric with the spindle main axis.
A timing pulley 108 is attached to the lower part of the spindle main shaft 102 and is configured to be rotated by a motor 110 via a timing belt 109. ing. The inner annular vacuum groove 107 communicates with a long hole 111 provided in the shaft of the spindle main shaft 102, and is connected to a vacuum pump (not shown) via a rotary joint 112 and a hose 113 attached to the lower end of the spindle main shaft 102. The air is being sucked by the air. The spindle main shaft 102 needs to be attached to the spindle case 101 with high rigidity to prevent axial movement and lateral wobbling, and for this purpose, it is preferable to attach it using an angular bearing, for example. The outer diameter of the tip of the hub locking protrusion 106 is the diameter of the clamping hole of the hub 20 (5
, 4mm for a 25-inch optical disc), and its clearance is 9.006mm.
It is preferable that it is within the range. In addition, the hub locking protrusion 106
It is preferable that the root portion of the tube has an outer diameter slightly smaller (about 1 mm) than the tip portion thereof. The recess 105 is a space for accommodating the hub that was joined first when joining two hubs when joining the hubs to both sides of the disk substrate 10, and when joining the first hub 20. A spacer 11 of a size corresponding to the hub is placed in the recess 105.
Enter 4. The reason why the base of the hub locking protrusion 106 is formed to have a slightly smaller outer diameter than the tip of the hub locking protrusion 106 as described above is that when joining two-piece hubs, the hub locking protrusion 106
This is to prevent movement of the disk substrate during centering from being restricted by the previously joined hub that passes through the disk. The motor 110 is preferably a stepping motor because the speed can be easily controlled and the rotation angle can be easily specified.

The disk eccentricity correction means is a known XYZ table (XYZ stage). That is, the disk eccentricity correction means includes a Z table 202 supported movably in the vertical direction by a Z direction fine movement mechanism 201 fixed to the base 1.
An X-direction fine movement mechanism 203 is fixed on the top, and an ) is fixed, and a Y table 205 is provided so as to be movable horizontally on the front and back sides of the paper in FIG. Z table 2
02, the X table 204 and the Y table 205 have a donut-like structure so as to surround the disk rotating means. The disk substrate mounting portion 206 of the Y table 205 is provided with an outer annular vacuum groove 207 for sucking the outer circumferential portion of the disk substrate 10, and the groove is sucked by a vacuum pump (not shown) via a hose 208. It has become. X table 20 outside the outer annular vacuum groove 207
A disk substrate stop member 210 is fixed to the upper surface 209 of the disk substrate 5 . The surface of the disk substrate stopping member 210 on the outer annular vacuum groove 207 side is connected to the disk substrate 1 placed thereon.
It is provided at a position such that it comes into contact with the outer peripheral end of 0. Further, an inclined surface 211 that descends toward the outer annular vacuum groove 207 is formed on the upper part of the disk substrate stop member 210 . This inclined surface 211 allows the outer circumferential portion of the disk substrate 10 to slide on the inclined surface 211 when the disk substrate 10 is placed.
The disk substrate 10 can easily enter inside the disk substrate stop member 210. Further, on the upper surface 209a of the X table 205 outside the outer annular vacuum chamber 207 on the opposite side of the part where the disk substrate stop member 2!0 is provided,
A disk substrate pressing plate support member 212 is fixed.

A disk substrate pressing plate 213 is reciprocatably attached to the disk substrate pressing plate support member 212, and a hose 214
The outer circumferential edge of the mounted disk substrate 10 can be pressed by the compressed air from the disk substrate 10, and the disk substrate pressing member 215 is composed of the disk substrate pressing plate support member 212 and the disk substrate pressing plate 213. .

The contact portion of the disk substrate pressing plate 213 with the disk substrate 10 is made of an elastic material. The portion of the disk substrate mounting portion 206 on the outer circumferential side of the outer annular vacuum groove 207 that faces the disk substrate pressing plate support member 212 has an outer circumferential edge that corresponds to the outer circumferential edge of the disk substrate 10 when the disk substrate 10 is placed thereon. In other words, the outer periphery of the disk substrate 10 is formed to slightly protrude from the disk substrate mounting portion 206. The disk substrate stopping member 210 and the disk substrate pressing plate supporting member 212 will be explained in more detail later.

Z table 202, X table 204 and X table 2
The stroke of 05 should be about ±1mm for each 5.25 inch disc, and the resolution is X table 2.
04 and the X table 205, and about 10 μm for the Z table 202. Also, Z
With the table 202, the upper surface of the disk substrate placement part 206 of the and lower than the disk substrate mounting surface 103 (“low” position). 5
．． In the case of a 25-inch disk, in the "high" position, the top surface of the disk substrate mounting section 206 is approximately 1 mm higher than the disk substrate mounting surface 103, and in the "low" position, the top surface of the disk substrate mounting section 206 is approximately 1 mm higher than the disk substrate mounting surface 103. It is approximately 1 mm lower than the substrate mounting surface 103.

The group area boundary detection means 300 detects the disk substrate 10
This is a means for detecting a boundary 12 between a group area 11 formed on the surface of a group area 11 and a portion where no group is formed. As a method for detecting the center of rotation of a group, since the light reflectance is different between the group area and the part where no group is formed, the above method is used to detect the boundary by measuring the reflectance of both. There is also a method of detecting any one track in a group area (even if the tracks are formed in a spiral shape, the track pitch is extremely small, so the tracks can be considered as concentric circles). In the present invention, either method may be adopted; in the case of the former method, a microscope, line sensor, CCD camera, etc. can be used as the group area boundary detection means 300; In some cases, optical pickups and the like can be used. 1st
In the figure, a combination of a microscope, a CCD camera, a CRT display, and a storage device is used as the group area boundary detection means 300.

As the ultrasonic fusion bonding means 400, those generally available on the market can be used. For example, an ultrasonic fusing machine can be used in which ultrasonic waves are generated by an ultrasonic transmitter 401 and transmitted through a converter 402 to an application horn 403. It has an application horn 403 with a tip shape as shown in FIG. 1, and is not of the type in which the hub 2° is attached in advance.

FIG. 2 is a top view showing the main parts of the disk rotating means and disk eccentricity correcting means in FIG. 1.

In FIG. 2, reference numbers that are the same as those shown in FIG. 1 have the same meanings as described with respect to FIG.

In FIG. 2, a hub locking projection 106 is provided at the center, four portions 105 are provided around the hub locking projection 106, and a disk substrate mounting surface 103 and an inner annular vacuum groove are provided around the recess 105. 107 is provided.

The upper surface 209 of the Y table is provided with an outer annular vacuum groove 207 outside the outer annular vacuum groove 207 (strictly speaking, an outer annular vacuum groove 207 which also serves as an outer wall of the disk substrate mounting portion 206, but for the sake of explanation below, an outer annular vacuum groove 207). A disk substrate stop member 210a and a disk substrate stop member 21 are placed outside the vacuum groove 207.
0b are fixedly provided at positions such that their surfaces on the outer annular vacuum 207 side abut against the outer circumferential ends of the disk substrates placed thereon. Further, the disk substrate stopping member 210a and the disk substrate stopping member 210b are provided so that the angle α with respect to the center of the hub locking protrusion 106 is 90°. Therefore, the disk substrate stop member 210a and the disk substrate stop member 2! Ob is within the same semicircle of the outer annular vacuum groove 207 (that is, the center line ■ in FIG.
- within the upper left half of H).

The disk substrate stop members 210a and 210b are made of a hard material such as metal, thermoplastic resin, thermosetting resin, etc., and are fixed to the top surface 209 of the Y table by, for example, screwing, gluing, or other means. is fixed to.

The upper surface 209 of the Y table further includes a hub locking protrusion 10 located between the disk board stop members 210a and 210b.
A disk substrate pressing plate support member 212 is fixedly provided on the upper surface 209a on the opposite side of the disk substrate 6.

A disk substrate pressing plate 213 is reciprocatably attached to the disk substrate suppressing plate support member 212, and a hose 214
The compressed air from the disk substrate can press the outer peripheral edge of the mounted disk substrate in the direction of arrow A toward the midpoint between the disk substrate stop members 210a and 210b. The contact portion 213a of the disk substrate pressing plate 213 with the disk substrate 10 is made of an elastic material, and the backing portion 21
3b.

Examples of the elastic material forming the contact portion 213a include natural rubber, butadiene rubber, isoprene rubber, acrylonitrile rubber, polyurethane rubber, butyl rubber, synthetic rubber such as silicone rubber, and ethylene-propylene-diene copolymer. However, any of various vulcanized rubbers and thermoplastic elastomers may be used. In particular, an elastic body with a high impact energy absorption rate and a large loss coefficient (tan δ) is preferable. A particularly preferred example of the above-mentioned elastic material is Sorposein (trade name, sold by Sanshin Kosan Co., Ltd.), which is an ether polyurethane obtained from polyol and MDI. In addition, the backing part 2
As the material of 13b, the materials exemplified above as the material of the disk substrate stopping member 210 can be mentioned.

The disk substrate pressing member 215 is a disk substrate pressing member 215.
13 is preferably capable of being pressed against the outer peripheral edge of the disk substrate with an arbitrarily controlled pressing force of up to about 10 kg/cm<2>.

As means for applying a pressing force to the disk substrate pressing plate 213, in addition to applying gas pressure such as compressed air as described above, liquid pressure may be applied, mechanical means such as a spring, or a magnet. For example, electromagnetic means such as

The contact surface of the disk substrate stopping member 210 with the outer peripheral edge of the disk substrate 10 may be a flat surface, a concave surface matching the outer circumferential arc of the disk substrate 10, or a convex surface, but depending on the outer peripheral shape of the disk substrate, Generally, there is a margin of error, and for convenience in manufacturing the disk substrate stopping member 210, it is desirable to make it flat.

Furthermore, it is conceivable to provide only one disk substrate stopping member 210 and to form the contact surface with the outer peripheral edge of the disk substrate 10 into a concave surface that matches the outer circumferential arc of the disk substrate 10; In order to fully achieve the effects of the present invention, in order to fully achieve the effects of the present invention, it is necessary to It is necessary to provide two substrate stops.

The angle α in FIG. 2 is between 60° and 150°, especially 90°.
It is preferable that it is -120 degrees.

Although FIG. 2 shows an embodiment in which one disk substrate pressing member is provided, two to three disk substrate pressing members may be provided.

Another example of the aspect of the device of the present invention in which the angle α formed by the disk substrate stopping member 210a and the disk substrate stopping member 210b with respect to the center of the hub locking protrusion 106 and the number of the disk substrate suppressing members 215 is as follows. FIG. 3 schematically shows only the disk substrate stopping member and the disk substrate pressing member.

In FIG. 3A, a disk substrate stopping member 210a and a disk substrate stopping member 210b are provided so that the angle α is 90°, and two disk substrate pressing members 21
5a and the disk substrate pressing member 215b are provided so as to face the disk substrate stopping member 210a and the disk substrate stopping member 210b, respectively.

In FIG. 3(B), a disk substrate stopping member 210a and a disk substrate stopping member 210b are provided so that the angle α is ]20°, and - disk substrate pressing members 2
Reference numeral 15 indicates a mode in which the disk substrate stopping member 210a and the disk substrate stopping member 210b are provided so as to face each other at the midpoint thereof.

In FIG. 3(C), a disk substrate stopping member 210a and a disk substrate stopping member 210b are provided so that the angle α is 90°, and two disk substrate pressing members 21
5a and the disk substrate pressing member 215b are provided to face the disk substrate stopping member 210a and the disk substrate stopping member 210b, respectively.
10a and the disk substrate stop member 210b are shown facing each other at an intermediate point.

Next, a method of joining a hub to a disk substrate using the hub joining apparatus shown in FIGS. 1 and 2 will be described.

(1) Two tables 202 by Z direction fine movement mechanism 201
to the "low" position. A spacer 1 is placed in the recess 105.
14, and place the disk substrate 10 on the disk substrate mounting surface 103 as shown in FIG.

(2) Next, actuate the disk substrate pressing member 212 to press the disk substrate 10 by the disk substrate pressing plate 213.
, whose outer peripheral ends are the disk substrate stop members 210a and 2
10b, a small force (e.g. 2 kg
/cm2 pressure). At this time, if the pressing force is too large, the disk substrate may be damaged.

(3) While pressing the disk substrate 10, suction is applied from the inner annular vacuum groove 107 to suction and fix the disk substrate 1o to the disk substrate mounting surface 103. Then release the pressure.

The hub 20 is placed on the disk substrate 1o.

As shown in a perspective view in FIG. 4, the hub 20 has a substantially annular shape, and has a clamping hole 21 formed in the center, a ring-shaped protrusion 22 on the outer periphery, and a sensitive plate on the opposite surface. A magnetic body (not shown) is attached. The hub 20 is
It is placed on the disk substrate 10 with the protrusion 22 facing down, the clamping hole 21 being fitted into the hub locking protrusion 106.

(4) Next, the position of the boundary 12 of the group area 11 is detected and stored by the group area detection means 300.

The position of the boundary 12 at this time is the boundary position in the 0° direction (Pa
). Next, the motor 110 is driven to rotate the spindle main shaft 102 through 90 degrees, and the position of the boundary 12 at that time is detected and stored. The position of the boundary 12 at this time is defined as a boundary position in the 90° direction (P 9o). Thereafter, in the same manner, the spindle main shaft 102 is rotated by 90°, and the position of the boundary 12 is detected each time.
). In this way, the boundary positions in the four directions are determined.

FIG. 5 shows these boundary positions projected on a CRT display. In Fig. 5, half of the difference (Dx) between Po and P180 is the eccentricity δ8 in the X direction, and half of the difference (Dy) between P9° and P270 is the eccentricity δ in the Y direction.
, and so on.

(5) Next, the two-direction fine movement mechanism 201 brings the Z table 202 to the "same" position. Outer annular vacuum groove 20
7 to suction and fix the disk substrate 10 to the disk substrate mounting portion 206 of the Y table 205. Next, suction from the inner annular vacuum groove 107 is stopped, and the disk substrate 10
is made free with respect to the disk substrate mounting surface 103.

(6) Next, the Z-direction fine movement mechanism 201 sets the second table 202 to the r-high position, and the X-direction fine movement mechanism 203
is activated to move the X-table 204 by the amount of eccentricity δ8 determined in (4) above in the direction in which the eccentricity becomes zero, and the Y-direction fine movement mechanism is activated to move the Y-table 205 by the amount of eccentricity δ8 determined in (4) above. It is moved by the amount of eccentricity δ7 in the direction where the amount of eccentricity becomes zero.

(7) Next, the two-direction fine movement mechanism 201 brings the Z table 202 to the “same” position, and the inner annular vacuum groove 107
The disk substrate 1o is also suctioned and fixed to the disk substrate mounting surface 103 by suction.

(8) Next, the disk substrate pressing member 215 is operated again, and the disk substrate 10 is pressed by the disk substrate pressing plate 213 with its outer peripheral end in contact with the disk substrate stopping members 210a and 210b, for example, 5 kg/ c.
Press with a pressure of about m2.

The pressing force at this time varies depending on the material and dimensions of the disk substrate, the frequency and energy of ultrasonic welding, etc., but is generally preferably 3 to 7 kg/cm<2>. If the pressing force is smaller than the above range, the vibration of the disk substrate during ultrasonic welding cannot be sufficiently absorbed, so that the object of the present invention cannot be fully achieved, and if the pressing force is larger than the above range. Otherwise, the disk substrate may be deformed.

(9) Next, with the disk substrate 10 being sucked by the inner annular vacuum groove 107 and the outer annular vacuum groove 207 &: and being pressed by the disk substrate pressing plate 213,
The ultrasonic fusion bonding means 400 is activated to fusion bond the hub 20 to the disk substrate 10 using a conventional method. At this time, the protrusion 22 melts and disappears, and the two are firmly joined.

(lO) Inner annular vacuum groove 107 and outer annular vacuum groove 20
Release the adsorption by 7 and take out the disk substrate to which the hub is joined.

Through the above process, the hub can be joined to one side of the disk substrate in a state where it is accurately centered on the center of rotation of the group of disk substrates. To bond the hub to the opposite surface of the disk substrate obtained in this way, the method is the same as described above except that the spacer 114 is removed and the disk substrate is placed so that the bonded hub is placed in the recess 105. All you have to do is connect the hub.

As is clear from the above description, when the hub is first joined to the disk substrate, the disk substrate mounting section 104
It is also possible to use a device in which the recess 105 is not formed.

Further, the optical disk may be a so-called magneto-optical disk in which a recording layer made of a magnetic layer is formed. In this case, the two resin substrates do not need to be assembled in a so-called air sandwich structure, and there is no need for inner and outer ring-shaped spacers. It goes without saying that the effects of the present invention are also exhibited in the assembly of this magneto-optical disk.

Further, the optical disk to which a hub can be joined using the apparatus of the present invention may be a so-called magneto-optical disk in which a recording layer made of a magnetic layer is formed.

As the hub and disk substrates that can be joined by the apparatus of the present invention, any known hub and disk substrates can be used as long as they can be joined by ultrasonic fusion.

The hub (magnetic hub) is not particularly limited as long as it bonds well with the disk substrate, and may be made of polycarbonate resin,
Mention may be made of thermoplastic resins such as polyacrylic resins and acetal resins.

Further, it is preferable that the hub is made of the same material as the disk substrate in consideration of the coefficient of thermal expansion and the coefficient of hygroscopic expansion.

The magnetically sensitive material required for the configuration of the hub (magnetically sensitive hub) is iron,
It is made of magnetically sensitive materials such as alloys containing iron,
It is preferable that it be made of a substance that does not easily rust. The form of the magnetically sensitive material is not particularly limited, but representative forms include magnetically sensitive pieces such as rods, plates, and rings, as well as magnetically sensitive bamboo powder in which the magnetically sensitive material is powdered. I can do it. Magnetically sensitive bamboo powder can also be kneaded into the hub material and then injection molded.

The material for the disk substrate can be arbitrarily selected from various materials conventionally used as disk substrate materials for optical information recording media, and preferably the same material as the hub.

An undercoat layer (and/or intermediate layer) may be provided on the surface of the disk substrate on the side where the recording layer is provided for the purpose of improving flatness, increasing adhesive strength, and preventing deterioration of the recording layer. .

Examples of materials used for the recording layer include Te, Zn, I
n, Sn, Zr, All, Ti%Cu.

Examples include metals such as Ge and Au%Pt; metalloids such as Bi, As, and Sb; semiconductors such as Si; and alloys thereof, or combinations thereof.

Compounds such as sulfides, oxides, borides, silicon compounds, carbides, and nitrides of these metals, semimetals, or semiconductors; and mixtures of these compounds and metals can also be used in the recording layer.

Alternatively, combinations of dyes, dyes and polymers, and dyes and the aforementioned metals and metalloids can also be used.

The recording layer may further contain various known metals, semimetals, or compounds thereof as recording layer materials.

The recording layer can be formed on the substrate-F directly or via an undercoat layer by using the above-mentioned materials by vapor deposition, sputtering, ion blasting, coating, or the like.

[Joining Example] Using the apparatus shown in FIGS. 1 and 2, hubs were bonded to both the front and back surfaces of a 5.25-inch disk substrate by ultrasonic fusion in the manner described above.

The eccentricity of the hub was measured for 100 disks joined under the same conditions. The results are shown below.

's m top - Plate plate 0 to less than 5 35 5 to less than 10 46 10 to less than 15 16 15 to less than 20 3 20 to less than 25 0 25 or more 0 [Comparative joining example 1] Using the device used in the joining example However, the disc substrate pressing plate support member 212 is not operated, that is, the pressing of the disc substrate in (2), and (8) and (9) is performed in the above method.
) Hubs were bonded to both the front and back surfaces of a 5.25-inch disk substrate by ultrasonic welding in the same manner as in the bonding example except that the disk substrates were not pressed in step 2). Therefore, this example shows the same joining example using the apparatus without the disk substrate pressing member and the disk substrate stopping member.

The eccentricity of the hub was measured for 100 disks joined under the same conditions. The results are shown below.

's m Jth [- 0 to less than 5 19 5 to less than 10 31 10 to less than 15 18 15 to less than 20 15 20 to less than 25 11 25 or more 6 It is clear from the comparison of the results of the joining example and comparative joining example 1 As shown, in Comparative Joining Example 1, six sheets had an eccentricity of 25 μm or more (outside the ISO standard) and could not be put to practical use, and even those with an eccentricity of less than 25 μm varied over a wide range and had eccentricity. The amount of eccentricity is large and the joining accuracy is poor, whereas in all the joining examples bonded using the device of the present invention, the amount of eccentricity is less than 20 μm, and the amount of eccentricity of less than 10 μm is 8
There is only one piece, and the joining accuracy is extremely excellent.

[Comparative joining example 2] An ultrasonic welding machine having a hub locking pin 404 at the center of the application horn 403° as shown in FIG. 6, and a hub locking protrusion 106 as shown in FIG. Using an ordinary XY table without a z-table and with the hub temporarily fixed to the application horn 403° by magnetic force, the process was carried out in the same manner as in [Comparative joining example 1] (using the disc substrate pressing member). Hubs were bonded to both the front and back surfaces of the disk substrate at a 10° angle by ultrasonic fusion.

The eccentricity of the hub was measured for 30 disks joined under the same conditions. The results are shown below.

"%m----Iv(-1 is ζ----0 to less than 5
2 5 to less than 10 5 10 to less than 15 4 15 to less than 20 7 20 to less than 25 3 25 or more 9 As is clear from the comparison of the results of the joining example and comparative joining example 2, in comparative joining example 2, 9 (30%) had an eccentricity of 25 μm or more and could not be put to practical use, and even those with an eccentricity of less than 25 μm varied over a wide range and had poor joining accuracy.

[Effects of the Invention] Although the hub joining device for optical information recording media of the present invention uses the ultrasonic fusion joining method which has the excellent features as described above, it is not affected by the vibrations of the ultrasonic fusion horn. The hub can be easily and stably attached to the disk board in a short period of time without being affected by the accuracy of the hole in the disk board, with the hub being precisely centered with respect to the center of rotation of the group of disk boards. Furthermore, it is possible to produce a disk of excellent quality without scratches, which is a remarkable advantage.

Furthermore, since the hub joining device for optical information recording media of the present invention does not require highly accurate alignment of the means for detecting group boundaries, the joining accuracy is stable even after long-term use without fear of deterioration. It also has the excellent effect of being able to be used in many ways.

[Implementation section] The following embodiments are preferred within the technical scope of the present invention.

2. The light source according to claim 1, wherein the disk substrate stopping member is made of a hard material, and the contact portion of the disk substrate pressing plate with the disk substrate is made of an elastic material. Device for hub joining of information recording media.

[Brief explanation of drawings]

FIG. 1 is a partially cross-sectional schematic diagram showing an embodiment of the hub joining device for optical information recording media of the present invention, and FIG. 2 is a main part of the disk rotation means and disk eccentricity correction means in FIG. 1. 3 is a top view schematically showing another aspect of the device of the present invention regarding the disk substrate stopping member and the disk substrate pressing member; FIG. 4 is a perspective view showing an example of the hub; The figure is a schematic diagram of the detected state of the boundary position of the group area of the disk substrate projected on a CRT display, and FIG. 6 is a schematic diagram of a part of the bonding apparatus used in Comparative Bonding Example 2. 1: Base, 10.10°: Disk substrate, 11 Niger loop area, 12: Boundary, 20: Hub,
21: Clamping hole, 22: Projection, 23:
Magnetically sensitive material, 101 Nissin spindle case, 102 Nissin spindle main shaft, 103: Disc substrate mounting surface, 104: Disc substrate mounting portion, 105: Recess, 106: Hub locking protrusion, 107:
Inner annular vacuum groove, 108: Timing pulley 109: Timing belt, 110: Motor, 111: Long hole, 112: Rotary joint, 113: Hose, 114 Varnish spacer, 201: Z
Directional fine movement mechanism, 202: Z table, 203: X direction fine movement mechanism, 204: X table, 205: Y table, 206: Disk substrate mounting section, 207: Outer annular vacuum groove, 208: Hose, 209:
upper surface, 210: disk substrate stopping member, 211: inclined surface, 212: disk substrate pressing plate support member, 213: disk substrate pressing plate, 214: hose, 215: disk substrate pressing member, 300 Nigel-pu region boundary detection means, 400: Ultrasonic fusion bonding means, 401: Ultrasonic transmitter, 402: Converter, 403.403°: Application horn, 404: Hub locking pin. Patent applicant: Fuji Photo Film Co., Ltd. Representative: Yasushi Yanagawa (patent attorney)

Claims (1)

[Claims] 1. An inner annular vacuum groove for adsorbing the inner circumference of the disk substrate is provided on the outer circumference, and a hub locking protrusion for fitting the clamping hole of the hub is provided at the center, and the disk substrate is mounted. A disk rotating means is rotatably provided on a spindle case fixed to a base with a spindle main shaft having a vertical surface at the upper end, and an outer circumferential portion of the disk substrate provided at a position surrounding the disk rotating means is attracted. an outer annular vacuum groove, two disk substrate stop members provided outside the outer annular vacuum groove and within the same semicircle of the outer annular vacuum groove, and the outer annular vacuum groove; A horizontally and vertically movable disk eccentricity corrector having a disk substrate pressing member on its upper surface, which is located on the outside of the hub and faces the two disk substrate stopping members across the hub locking protrusion. 1. An apparatus for joining hubs of optical information recording media, comprising at least a means for detecting a group or a group area boundary formed on the disk substrate, and a means for joining hubs by ultrasonic welding.