JP2000100123A - Optical storage medium loading apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical storage medium loading apparatus which prevents drop of holding force of an optical disk made of resin which is often seen in the optical disk recording and reproducing apparatus because a plurality of optical disks made of resin are held with pressure by a clamp ring and are tightened to a spindle hub, the optical disk generates a creep to increase distortion with passage of time due to such compressive load, and the force to tighten the optical disk to the spindle hub is reduced due to drop of disk holding force. SOLUTION: In an optical storage medium loading apparatus, an optical storage medium, which is formed by an optical storage medium 10 and a spacer ring 21 are alternately laminated to a collar type receiving surface 20a provided to the spindle hub 20 and the optical storage medium is depressed and held by a clamp ring 22 from the final end surface, is depressed and held with spring element functions (1), (5). As explained above, since the spring element functions are give to the loading apparatus, drop of optical disk holding force can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for mounting a plurality of resin optical recording media, and more particularly, to a recording / reproducing head which approaches or contacts a recording layer of an optical recording medium. The present invention relates to an apparatus for mounting a plurality of resin optical recording media used in an optical recording medium recording / reproducing apparatus for performing the above.

[0002]

2. Description of the Related Art An optical recording medium (hereinafter referred to as an optical disk) on which information can be written and / or read by a laser has a larger recording capacity and a random access than conventional recording media. It is widely used as a recording medium in fields such as audio software, computer software, game software, and electronic publishing.

[0003] Further, with the development of computer technology, the capacity of recording devices has been steadily increasing. Conventional optical disks include a read-only type (ROM), a rewritable type (RAM), and a write-once type. In these media, an optical head is provided on the side opposite to the recording surface of the optical disk substrate. The so-called substrate surface incidence method is adopted in which the reading light or the recording light emitted from the substrate passes through the substrate and reaches the recording surface. Since the optical head is provided with an objective lens movable in the direction of the focal axis by an actuator so that these lights are focused on the recording surface, the distance between the optical head and the disk is usually about 1 mm.

On the other hand, in recent years, as a recording / reproducing apparatus having a large capacity and high-speed access, an apparatus using an existing various optical disk as a hard disk has been proposed (Nikkei Mechanical 1998.05, No.524, P.58, etc.). reference). That is, a plurality of optical disks are built in, an optical head is provided to face each recording surface, and recording / reproduction is performed by so-called film surface incidence without a substrate. In the conventional substrate incidence method, the numerical aperture of the objective lens could not be increased because the aberration of the light spot increased due to the inclination of the substrate and errors in the thickness of the substrate. By increasing the numerical aperture and reducing the light spot,
Larger capacity of optical disk and high-speed access like hard disk became possible.

FIG. 4 is an example of a conventional recording / reproducing apparatus, which is a partially omitted cross-sectional view of the entire apparatus. Six double-sided recording type optical discs 10 are alternately arranged with a spacer ring 21 interposed on the outer periphery of a spindle hub 20. , And pressed and held by the clamp ring 22 from the final end face.
Note that a resin substrate is used for the substrate of the optical disk 10 as in the case of a conventional optical disk. The spindle hub 20 is rotatably supported on the spindle shaft 25 via bearings 23A and 23B integrally with the optical disc 10.

The optical head 40 is supported by a head support arm 41 so as to sandwich each optical disk 10. The laser light is transmitted to the optical head 40 up to the head end by an optical fiber (not shown). A micromirror is incorporated at the tip of the head, and the transmitted laser light is turned by the mirror toward the medium. By controlling the direction of the micro mirror, servo for recording and reproduction is performed. The support arm 41 is supported by a cylindrical arm support section 42. Further, the arm support portion 42 includes bearings 43A, 43B.
The drive means 45 is rotatably supported by a head rotating shaft 44 via a drive arm 45 and is provided on a side opposite to the support arm 41 so that the optical head 40 can reciprocate in the radial direction on the disk surface of the optical disk 10. And it is designed to swing and rotate at high speed.

The distance between the optical disk 10 and the optical head 40 differs depending on the optical head, but is usually set to 3 μm or less. In the case of a flying head in which a lens, a reflecting mirror, or an optical fiber is installed on a flying slider, in order to maintain this distance, the spring pressure of the support arm 41 that presses the slider against the disk and the buoyancy required for flying are obtained. The area and shape of the slider section can be set. Further, a contact type head in which a slider portion and a disk surface are partially in contact has been proposed.

When recording information sent from the outside, each head detects address information (physical position on the substrate) based on a pre-recorded preformat and records the information on the opposing optical disk. Record information in layers.
The information may be recorded by using only one head or both heads simultaneously. When reading information recorded on a disc, the position of the recorded information is searched for and read by a head. At this time, each head may independently perform servo adjustment on recorded information so as to maximize the reproduction signal intensity. Even when the head position when the rotation of the disk is stopped is in contact with the disk as in the so-called CSS method, it is close to or in contact with the disk only during rotation of the disk as in the dynamic loading method,
When the disk is stopped, it may be sufficiently away from the disk. In addition, in this type of recording / reproducing apparatus, it is considered that the rotation speed of the spindle hub 20 becomes a high-speed rotation of, for example, 4500 rpm to 5400 rpm, and further 7200 rpm with an increase in data transfer rate along with an increase in storage capacity.

[0009]

According to the study of the present inventors, it has been found that the following problems occur when an optical disk is used in the recording / reproducing apparatus. That is, in the optical recording medium recording / reproducing apparatus of the present invention, a plurality of resin optical disks are stacked, and the resin optical disk is pressed and held by the clamp ring, so that a compressive load is constantly applied. This compressive load causes creep, and the distortion of the resin optical disk increases with time, the holding force of the plurality of optical disks pressed and held decreases, and the force of fastening the optical disk to the spindle hub decreases. I do.

As a matter of course, the creep phenomenon becomes more remarkable as the number of optical recording media to be stacked increases. In particular,
When the recording / reproducing apparatus has been used for a long time, the temperature inside the recording / reproducing apparatus becomes high due to the heat generated by the laser, the motor, and the like, and the creep phenomenon is accelerated, so that the fastening problem of the optical disk becomes remarkable. In order to reduce the creep phenomenon, an optical disk substrate material having a small creep is required in addition to the mounting method, but there are few optimal substrate materials that can withstand practical use in manufacturing the optical disk of the present invention.

It is an object of the present invention to solve these problems and to provide an optical disk mounting apparatus suitable for use in such a recording / reproducing apparatus. That is, when mounting a plurality of optical discs on a recording / reproducing apparatus, if a specific mounting apparatus is used, even if a creep phenomenon occurs on a plurality of resin optical discs, a plurality of optical discs can be mounted on a spindle hub. We found that optical discs could be fastened without any problems.

[0012]

SUMMARY OF THE INVENTION The gist of the present invention is to sequentially stack and mount optical recording media on a flange-shaped receiving surface provided on the outer periphery of a spindle hub with a spacer ring interposed therebetween, and to clamp the optical recording medium from its final end surface. An apparatus for mounting an optical recording medium, wherein the optical recording medium is pressed and held by a ring, wherein the optical recording medium is pressed and held by imparting a spring element function.

[0013] The present invention is also an optical recording medium mounting apparatus provided with a spring element function by a disc spring.

The clamp ring has a disk shape. A protrusion is provided on a pressing surface of the clamp ring, and a plurality of screw through holes for screwing the clamp ring to the spindle hub are arranged on the circumference. An optical recording medium mounting device having a cutout portion between through holes and imparting a spring element function by the cutout portion.

Further, the spring constant of the spring element is 0.1 M
An optical recording medium mounting device having a capacity of N / m to 100 M · N / m.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An optical recording medium mounting apparatus according to the present invention will be described below in detail with reference to the drawings. FIG. 1 is a partially omitted sectional view showing an embodiment of the present invention, FIG. 2 is a perspective view of a disc spring used in the present invention, FIG. 3A is a plan view of a clamp ring used in the present invention, FIG. 4B is a cross-sectional view taken along line AA of FIG. 4A, and FIG.

First, in the embodiment shown in FIG. 1, the spindle assembly 30 of the optical recording medium recording / reproducing apparatus 50 includes a spindle hub 20, a spacer ring 21, and six optical discs 1.
0, a clamp ring 22, a spindle shaft 25, and the like. The spindle hub 20 is cylindrical, and a lower end portion 20A of the spindle hub forms a flange-shaped optical disc receiving surface. Six optical disks 10 and spacer rings 21 are alternately stacked on the outer periphery of the spindle hub 20. Further, a disc-shaped clamp ring 22 for pressing and holding the uppermost surfaces of the six optical disks is provided at the final end of the spindle hub 20. The spindle hub 20 includes a spindle shaft 25 rotatably supported via bearings 23A and 23B.

Further, in FIG. 1, the uppermost optical disc 10 "is pressed and held by the annular projection 4 provided on the clamp ring 22 via the disc spring 1 and the top spacer ring 2, and this disc spring 1 holds the optical disc. In addition, the clamp ring 22 has a cut-out portion 5, and the cut-out portion 5 allows the spring element to press and hold the optical disk. It has the effect of adding functions.

This will be described in more detail with reference to FIGS. The disc spring 1 shown in FIG. 2 is made of stainless steel or the like by press working or the like. Although FIG. 1 shows a case in which one disc spring is sandwiched, the number of the sandwiched springs and the position of the sandwiching are appropriately selected in consideration of the creep amount of the resin substrate, the pressing and holding force, and the like. When a plurality of disc springs are used, there is a method of laminating them in the same direction or using them in opposite directions, but is appropriately selected depending on the above-described creep amount, pressure holding force, and the like.

The clamp ring 22 shown in FIG. 3 is provided with six through holes 6 on the circumference for screw fastening to the spindle hub 20. Also, clamp ring 2
An annular projection 4 is formed on the pressing surface side of the outer peripheral portion of 2, and the tip of the annular projection is processed into an R shape. Further, between the through hole 6 of the screw and the annular projection 4, a concave notch 5 is formed in an annular shape on both sides. The notch 5 has an effect of imparting a spring element function when the optical disk is pressed and held.

The clamp ring 22 is made of aluminum, stainless steel or the like. When the clamp ring 22 is screwed to the spindle hub 20, the clamp ring 22 is assembled so that there is no displacement of the clamp ring 22 and a uniform tightening stress is generated on the plurality of optical disks 10. In this embodiment, in order to eliminate the displacement, the design is such that the concave portion 7 of the clamp ring 22 is fitted to the convex protrusion 8 of the spindle hub 20. This fitting gap is 0.05 to 0.1 m
About m is preferable for assembly work. In FIGS. 1 and 3, the protrusion 4 and the notch 5 are provided over the entire circumference of the disk-shaped clamp ring 22. For example, the protrusion 4 and the notch 5 are provided around the clamp ring 22. A plurality can be provided along.

Next, the fact that the tightening force of the clamp ring 22 is reduced by the creep phenomenon of the resin substrate of the optical disk 10 will be described in detail. Generally, the resin material is
Due to the tensile or compressive stress, the strain (elongation or shrinkage) increases with the passage of time, and after a certain period of time, the strain is almost in an equilibrium state. The amount of strain due to this stress is greater for tensile stress than for compression. In this mounting device, the amount of strain (shrinkage) is several percent at the maximum although the stress is compressive. If only one substrate is mounted, even this amount of distortion can be avoided by tightening the clamp ring 22, but the optical recording medium recording / reproducing apparatus mounts six optical disks, so that the amount of distortion is small. Cannot be ignored.

When contraction distortion occurs in the six optical disks 10, a gap is generated between the clamp ring 22 and the tightening portion of the optical disk 10, and the tightening force of the optical disk is reduced. As a result, the optical disk 10 becomes almost idle and cannot rotate the optical disk 10 at a desired rotation speed. This phenomenon is different from the loosening of screws that is usually called in mechanical devices.

A spring element function is provided to the clamp ring 22 or a spring element function is provided by using the disc spring 1 so that the distortion of the optical disk 10 is absorbed by these spring element functions. As a result, it is possible to prevent a decrease in the fastening force of the optical disc 10 mounted on the spindle hap 20. However, even though the spring can absorb the strain, the strain is generated, so that it is unavoidable that the initial tightening force is slightly reduced. The spring constant of the spring used in this embodiment is 0.1 M (mega) · N / m to 100
The range of M · N / m is preferred, and more preferably 10M ·
N / m to 50 M · N / m is preferable. By selecting a spring in this range, it is possible to minimize a decrease in the tightening force due to creep of the optical disk 10.

The optical disk used in the present invention is not particularly limited as long as it has a writable recording layer.
Those using a phase change method are preferred. The magneto-optical method is excellent in rewriting durability, and can be repeatedly rewritten 1 to 10 million times. The phase change method has an advantage that the optical system can be simplified because the read signal is a method of modulating the intensity of the reflected light. Also, using a dye etc. as a write-once method that can be written only once,
A writing method using drilling or deformation may be used. Further, the optical disc is provided with a preformat including coast information accessible by a head for reading and writing. Specifically, the address information includes address information such as a track address and a sector address, rotation synchronization information, and tracking servo information. A preformat used for an existing optical disc may be used as it is.

The above-mentioned preformat may be provided on both sides of a double-sided recording type optical disk, but may be provided on only one side. At the time of manufacturing a disc, usually, a mold including addresses and tracking information is prepared, a pre-formatted substrate is prepared using the mold, and a layer such as a recording layer is formed as necessary to form an optical disc. . There are various methods for manufacturing substrates, such as injection molding, casting, press molding, and methods using photo-curable resins. It is preferable. Burnishing may be performed in order to reduce protrusions on the substrate surface. In the case of a double-sided recording type optical disk, the two disks may be bonded together with an adhesive with the substrate inside. Alternatively, a substrate such as a recording layer may be formed on both sides as necessary after preparing a substrate that is preformatted simultaneously on both sides by using two molds.

[0027]

As described above, according to the present invention, in an optical disk recording / reproducing apparatus, in particular, in an apparatus for mounting a plurality of resin-made optical disks, a plurality of optical disks are always pressed and held on a spindle hub by a clamp ring and fastened. Even if the pressing force causes creep to occur on the optical disk and the distortion increases with time and the holding force of the optical disk decreases, the spring device function is provided to the mounting device as in the mounting device of the present invention. Accordingly, it is possible to prevent the holding power of the optical disk from being reduced. Therefore, the rotation of the spindle hub is reliably transmitted to a plurality of optical disks, and recording and reproduction can be performed at a desired number of rotations without causing the optical disk to idle.

[Brief description of the drawings]

FIG. 1 is a partially omitted cross-sectional view showing one embodiment of the present invention.

FIG. 2 is a perspective view of a disc spring used in the present invention.

FIG. 3 is a front view and a sectional view of a clamp ring used in the present invention.

FIG. 4 is a cross-sectional view of a conventional example in which the entire device is partially omitted.

[Explanation of symbols]

 Reference Signs List 1 disc spring 2 top spacer ring 4 annular protrusion 5 annular notch 6 screw through hole 10 optical disk substrate 20 spindle hub 20A flange-shaped receiving surface 21 spacer ring 22 clamp ring 25 spindle shaft 30 spindle assembly 50 optical recording medium recording / reproducing apparatus

Claims (4)

[Claims] 1. An optical recording medium is sequentially laminated and mounted on a flange-shaped receiving surface provided on an outer periphery of a spindle hub with a spacer ring interposed therebetween, and the optical recording medium is pressed and held by a clamp ring from its final end surface. An optical recording medium mounting device comprising: a holding device for holding an optical recording medium by imparting a spring element function. 2. The optical recording medium mounting device according to claim 1, wherein a spring element function is provided by a disc spring. 3. The clamp ring is disk-shaped, and a projection is provided on a pressing surface of the clamp ring, and a plurality of screw through holes for screwing the clamp ring to the spindle hub are arranged on the circumference, and the projection and the projection are connected to each other. 2. The optical recording medium mounting device according to claim 1, wherein a notch is provided between the screw through holes, and the notch provides a spring element function. 4. The spring constant of the spring element is 0.1 M · N /
2. The optical recording medium mounting device according to claim 1, wherein the value is from m to 100 M · N / m.