JP4181265B2 - Rotation balance correction device and disk drive device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rotation balance correction apparatus and a disk drive apparatus that automatically adjust a weight imbalance during rotation of a disk-shaped information recording medium such as a CD-ROM or DVD (digital video disk).
[0002]
[Prior art]
Conventionally, as this rotation balance correcting device, a type that is mounted on the rotor side of a motor and a type that is mounted on a clamper that holds a disk are known.
[0003]
In the disk drive device described in Japanese Patent Laid-Open No. 10-320877, a rotation balance correcting device is provided inside the clamper. This rotation balance correcting device is configured to accommodate a solid balance member in a hollow annular portion so as to be movable and to rotate integrally with a disk. When the solid balance member moves in the direction of balancing in the hollow annular portion during rotation, vibration generated during high-speed rotation of the disc can be suppressed even for the disc that is automatically balanced and eccentric. It is like that.
[0004]
[Problems to be solved by the invention]
However, since the conventional rotation balance correction device is attached to the rotor side of the motor or a small-diameter portion such as a clamper, in order to respond to the request for double the rotation speed, the current state of high-speed rotation is progressing. However, it may not be sufficient to cancel the centrifugal force generated by the unbalance of the large-diameter disk itself (hereinafter referred to as unbalance force), and the unbalance force during rotation caused by eccentricity may still remain large. . For this reason, the vibration generated during the rotation becomes large, an error in reading the information recorded on the disk may occur, and the unbalance force may not be supported by the clamp force of the clamper that supports the disk. Also, at the time of high-speed rotation, the trouble that the clamper comes off and the disk is scattered occurs.
[0005]
In addition, it is conceivable to increase the mass of the balance member in order to improve the problem that the unbalance force cannot be corrected due to the small mounting radius of the balancer. The volume of the part increases, the balance correction device itself becomes larger, and the disk drive device in which this balance correction device is used must be enlarged. Further, when such a balance member having a large mass is used, there is a problem that the balance member is prevented from moving in a smooth and precise balance direction, and the unbalance force cannot be corrected with high accuracy.
[0006]
The present invention solves the above-described conventional problems, and a rotational balance correcting device and a disk capable of improving the correction performance for canceling the unbalance force possessed by the disk itself without increasing the mass of the balance member. An object is to provide a drive device.
[0007]
[Means for Solving the Problems]
The rotation balance correction device of the present invention is a rotation balance correction device that automatically adjusts the weight imbalance of a disk-shaped information recording medium during rotation, a disk-shaped portion having at least the same diameter as the disk-shaped information recording medium, The outer periphery of the disk-shaped part includes an outer periphery having an annular hollow path and a plurality of spheres movable within the hollow path. The outer periphery of the disk-shaped part is disc-shaped information. It is located outside in the radial direction of the recording medium .
[0008]
With this configuration, it is possible to easily attach the balancer up and down by frictional force or the like simply by positioning the disk-shaped portion of the rotation balance correction device (balancer) on the disk-shaped information recording medium. Is positioned on the outer circumference side of the disc-shaped information recording medium, so that the unbalance force possessed by the disc itself can be effectively canceled and the balancer has a larger mounting radius than the conventional one, so that the balance member (sphere) It is possible to increase the correction amount for the unbalance force without increasing the mass of the lens and to improve the correction performance for more precise correction since the balance member can be easily moved by a sphere. As a result, the vibration of the disk during rotation is reduced and scattering of the disk is also prevented.
[0009]
Preferably, the disc-shaped portion in the rotation balance correcting device of the present invention has a circular recess into which the outer peripheral portion of the disc-shaped information recording medium can be fitted.
[0010]
With this configuration, the disc-shaped portion of the rotation balance correction device (balancer) is fitted to the disk-shaped information recording medium, so that the integration of the disk-shaped information recording medium and the rotation balance correction device is more reliable. It is possible to counteract the unbalance power possessed by the disk itself more effectively.
[0011]
Further preferably, in the rotational balance correcting device of the present invention, the outer peripheral portion includes an encircling portion extending from the peripheral end of the disk-shaped portion and having an upper surface opened, and an annular shape covering the upper surface of the encircling portion. And a lid.
[0012]
With this configuration, since the sphere is accommodated in the surrounding portion and covered with the lid, it is easy to accommodate the sphere in the hollow path.
[0013]
Furthermore, in the rotation balance correcting device of the present invention, it is preferable to use a steel ball as a sphere, and this configuration ensures a sufficient correction mass even if the diameter is small because the steel ball has a high specific gravity (density). It is possible but does not increase in size.
[0014]
Further preferably, the hollow path in the rotation balance correcting device of the present invention has an arc shape in which the longitudinal cross-sectional shape at least on the outer peripheral inner surface side is larger than the diameter of the sphere.
[0015]
With this configuration, if the vertical cross-sectional shape of the inner surface of the outer periphery of the hollow path is an arc shape larger than the diameter of the sphere, even if the sphere moves to the outer peripheral side of the sphere moving path due to centrifugal force during rotation, the hollow path There is only one point of contact between the inner surface outer peripheral side and the sphere, and the sphere can move in the balance direction with a smaller resistance, so that the balance correction is performed more smoothly and accurately.
[0016]
The disk drive device of the present invention is provided with a disk holding surface capable of holding a disk-shaped information recording medium to which the rotation balance correcting device according to any one of claims 1 to 4 is attached so as to be able to rotate. It is a feature.
[0017]
With this configuration, the rotation balance correcting device (balancer) of the present invention can be easily applied to the disk drive device, and the correction amount for the unbalance force during rotation can be increased for the disk drive device, too. By obtaining the effect of the present invention that improves the correction accuracy and reducing the vibration of the disk, more accurate data writing and reading can be performed on the disk.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a partially broken perspective view showing an embodiment of a rotation balance correcting device according to the present invention. FIG. 2 is a diagram showing a state in which the rotation balance correcting device of FIG. It is a longitudinal cross-sectional view of the rotation balance correction apparatus in the state. 1 and 2, the rotational balance is corrected for a circular disk-shaped information recording medium 3 (hereinafter referred to as a disk 3) placed on a disk holding surface on a turntable 2 attached to a rotating shaft of a motor 1. A disk-shaped information recording medium balancer 4 (hereinafter referred to as a balancer 4) as a device is mounted from above, and the disk 3 is fixed by a clamper 5 from above. These motor 1, turntable 2 and clamper 5 constitute a disk drive device 6, and the turntable 2 is driven to rotate by the motor 1. The balancer 4 and the clamper 5 may be formed integrally or may be configured separately.
[0019]
The balancer 4 includes a disc-like portion 42 having a circular recess 41 into which the outer periphery of the circular disc 3 can be fitted, and an annular hollow passage 43 provided around the outer peripheral end of the disc-like portion 42. The outer peripheral part 44 which has and the spherical bodies 45, such as a some steel ball which can move the inside of this hollow path 43 in the circumferential direction, are provided.
[0020]
The hollow path 43 of the outer peripheral part 44 is a spherical body moving path, and extends outward from the peripheral end of the disk-shaped part 42 and has an encircling part 431 having an upper opening, and an annular lid that covers the upper opening. The vertical cross-sectional shape of the body 432 is substantially square. The plurality of spheres 45 are easily stored in the hollow passage 43 with the lid 432 removed, and then covered with the annular lid 432 and fixed with an adhesive or the like so that the hollow passage 43 is formed. It has become. Further, the hollow path 43 that is a spherical moving path is made of a rigid material such as a light metal material whose inner surface shape hardly changes.
[0021]
The spherical body 45 has a slightly smaller size diameter so that it can move inside the longitudinal section of the hollow passage 43.
[0022]
The clamper 5 regulates the movement of the disk 3 by fitting and engaging with the central protrusion 8 of the turntable 2.
[0023]
With the above configuration, when the turntable 2 starts rotating around the axis CL together with the rotating shaft of the motor 1, the disk 3 and the balancer 4 mounted on the turntable 2 also start rotating together with the clamper 5. At this time, the disc 3 itself vibrates due to non-uniformity in the weight of the disc 3 (such as a deviation of the center of gravity due to printing on the surface of the disc 3). By moving in the balance direction opposite to the biased center of gravity position, the non-uniformity in weight of the disk 3 (bias of center of gravity) is canceled and balance correction is performed, and vibration of the disk 3 is suppressed even at high speed rotation. Stable rotation.
[0024]
As described above, according to the present embodiment, since the balancer 4 is mounted on the disk 3 and is located on the outer peripheral side, the unbalance force that the disk 3 itself holds during rotation by the balance force of the balancer 4. Since the mounting radius of the balancer 4 is larger than that provided in the clamper 5 as in the prior art, centrifugal force acts well on the sphere 45 and the mass of the sphere 45 is increased. The correction amount for the unbalance force can be increased without setting, and the correction accuracy can be improved by reducing the outer diameter of the sphere 45 and increasing the number. As a result, vibration during rotation of the disk 3 can be further reduced to prevent occurrence of reading errors and scattering of the disk 3 as in the prior art.
[0025]
In this way, an unbalance during rotation of the disk 3 can be canceled by an assembly in which the balancer 4 is mounted around the disk 3. Moreover, since the balancer 4 can be mounted around the disk 3 in a place with a large mounting radius, even a member having a small specific gravity (density) is effective instead of the steel ball of this embodiment. It can be used as a balance corrector. As a result, the balance correcting body can be formed from an elastic member such as resin or rubber, and no collision sound is generated by the spheres 45. Further, the balance correction effect is adversely affected by friction between the sphere 45 and the hollow passage 43, but since the balance correction body is the sphere 45, the influence of friction is small, and the balance correction effect is reproduced at a higher rated rotational speed. The property is also good.
[0026]
Further, it can be easily mounted by simply fitting the circular recess 41 of the balancer 4 from above the circular disk 3. Further, since the circular recess 41 of the disk-like portion 42 is fitted to the disk 3, the unification force possessed by the disk 3 itself is obtained because the integration of the disk 3 and the balancer 4 is more reliable. Can be canceled more effectively.
[0027]
Furthermore, since the plurality of spheres 45 are accommodated in the surrounding portion 431 and covered with the lid body 432, the plurality of spheres 45 can be easily accommodated in the hollow path 43.
[0028]
Furthermore, since the spherical body 45 as the balance member is a steel ball, the steel ball has a large specific gravity (density). Therefore, even if the size (size) is reduced, a sufficient correction mass can be obtained, and the outer peripheral portion 44. The hollow path 43 that is the spherical moving path can be made small.
[0029]
Furthermore, the balancer 4 of the present invention can be easily applied to the disk drive device 6, thereby increasing the correction amount for the unbalance force during rotation and improving the correction accuracy to reduce the vibration of the disk 3. The disc drive device 6 that can be provided can be provided, and thereby data can be written to and read from the disc 3 with higher accuracy.
[0030]
In this embodiment, the example in which the balancer 4 is mounted from above the disk 3 has been described. However, as shown in FIGS. 3 and 4, the balancer 7 as an example of a balance correction apparatus mounted around the disk 3 will be described below. Will be described in detail.
[0031]
The balancer 7 includes a ring member 72 having a hollow path 71 as a spherical moving path therein, and a plurality of spheres 73 accommodated in the hollow path 71. The ring member 72 is formed of a stretchable elastic body such as rubber, and an annular groove 74 for mounting a disc that can be fitted to the outer peripheral edge of the disc 3 is formed on the inner peripheral surface side of the disc 3. is doing. Further, the ring member 72 is provided with one sphere inlet 75 on the upper surface, and the sphere 73 is accommodated in the hollow passage 71 from the sphere inlet 75. The spherical body entrance 75 is closed with a lid (not shown). Further, the balancer 7 is mounted on the outer periphery of the disk 3 by using the elasticity of the ring member 72 to expand the inner diameter and mounting the balancer 7 on the outer peripheral edge of the disk 3.
[0032]
That is, as a method of attaching the balancer 7, an elastic ring member 72 is fitted in a state in which the outer peripheral edge portion on one side of the disk 3 is fitted in an annular groove 74 formed on the inner peripheral surface side of the ring member 72. The balancer 7 can be easily mounted on the disk 3 and the balancer 4 can be mounted on the disk 3 simply by accommodating the outer peripheral edge of the other side of the disk 3 in the annular groove 74. The balancer 4 can be mounted at a location where the mounting radius is large. In this case, the dimensional relationship is such that no stress acts on the ring member 72 so that the inner surface shape of the hollow path 71 is not deformed in a state where the outer peripheral edge of the disk 3 is fitted in the annular groove 74. A material having a shape memory function may also be used for the inner surface shape portion of the hollow path 71. The ring member may be made of a material having a high coefficient of thermal expansion instead of an elastic body such as rubber, and the inner diameter thereof may be enlarged / reduced using heat, or a disk is mounted using a shape memory resin or the like. The inner ring groove may be mounted on the outer periphery of the disk with its inner diameter being increased while changing the shape of the annular groove.
[0033]
In the present embodiment, the hollow passages 43 and 71 have an inner surface having a quadrangular longitudinal cross section, and when the spheres 45 and 73 are moved closer to the outer periphery of the inner surface of the hollow passages 43 and 71 during rotation, Although the example in which the inner surface of the air passage 43 and the inner surface of the sphere 73 and the inner surface of the hollow passage 71 are in contact with each other has been described, the present invention is not limited to this, and as shown in FIG. If the inner longitudinal cross-sectional shape is an arc-shaped portion 83 larger than the diameter of the sphere 82, the sphere 82 and the inner surface of the sphere moving path 81 come into contact at one point during rotation. As a result, when the sphere 81 moves during rotation, the sphere 81 can move in the balance direction with a smaller resistance, and unbalance correction is performed more smoothly and precisely. Further, in addition to the outer peripheral side of the inner surface of the hollow path 81, an arc-shaped portion 83 may be formed not only on the inner peripheral side but also on the inner peripheral side so that the longitudinal section has a shape with no corners such as an ellipse. .
[0034]
In this embodiment, the balancer 4 is manually mounted on the disk 3. However, the present invention is not limited to this, and the disk drive device 6 automatically mounts the balancer 4 on the disk 3 (not shown). It is also possible to perform it automatically using.
[0035]
Furthermore, in this embodiment, after the plurality of spheres 45 are accommodated in the groove from the upper open portion of the hollow path 43 that is a sphere movement path, the annular lid member 432 is fixed with an adhesive to close the hollow path 43. If a plurality of spheres 45 are accommodated from the upper open portion of the hollow passage 43 and then the annular lid member 432 is engaged by fitting or the like so as to be detachably fixed, the disc 3 is fixed. Accordingly, the number of the plurality of spheres 45 can be changed to perform better unbalance adjustment.
[0036]
Furthermore, in this embodiment, the sphere 45 made of steel balls is used as the balance moving body. However, the present invention is not limited to this, and the sphere 45 may be a granule, powder, or liquid, a cylindrical or rod-shaped rolling element, A spring coil or the like may be used. In short, any shape or material may be used as long as the moving body moves more smoothly and precisely in the balance direction. Therefore, if the inner surface of the hollow path 43, which is a spherical body movement path, is subjected to a surface treatment so that the friction is reduced, a smooth and precise balance movement can be achieved even with a sliding body in addition to a rolling element.
[0037]
【The invention's effect】
As described above, according to the first aspect, since the balancer is mounted on the disk and located on the outer peripheral side, the unbalance force that the disk itself holds during rotation can be easily eliminated by using the automatic balance function of the balancer. In addition, since the mounting radius of the balancer is large, the correction amount for the unbalance force can be increased without increasing the mass of the sphere, and the balance correction accuracy can be improved. As a result, vibration during rotation of the disk can be reduced and scattering of the disk can be prevented.
[0038]
According to the second aspect of the present invention, it is possible to easily mount the circular disc-shaped information recording medium simply by fitting the circular concave portion. In addition, since the circular recess is fitted to the disc-shaped information recording medium, the disc-shaped information recording medium and the rotation balance correcting device are more reliably integrated, and the unbalance force that the disc itself has. Can be canceled more effectively.
[0039]
Furthermore, according to the third aspect, since the plurality of spheres are accommodated in the surrounding portion and covered with the lid, the plurality of spheres into the hollow path can be easily accommodated.
[0040]
Furthermore, according to claim 4, if the sphere as the balance member is a steel ball, the specific gravity (density) is large, so that a sufficient correction mass can be obtained even if the size (size) is reduced. .
[0041]
Further, according to claim 5, if the cross-sectional shape inside at least the outer periphery of the hollow path is an arc shape larger than the diameter of the sphere, there is only one point of contact between the hollow path and the sphere when the sphere moves during rotation. Thus, the sphere can move in balance with a smaller resistance, and unbalance correction can be performed more quickly and accurately.
[0042]
According to the sixth aspect of the present invention, the balancer can be easily applied to the disk drive device, and the correction amount for the unbalance force at the time of rotation is increased for the disk drive device and the correction accuracy is improved. The balance correction effect of the present invention can be obtained, and the vibration of the disk can be reduced, so that more precise data can be written to and read from the disk.
[Brief description of the drawings]
FIG. 1 is a partially broken perspective view showing an embodiment of a rotation balance correcting device according to the present invention.
2 is a longitudinal sectional view of the rotation balance correcting device in a state in which the rotation balance correcting device of FIG. 1 is mounted on an information recording medium and incorporated in a disk drive device.
FIG. 3 is a perspective view showing an external configuration of a rotation balance correcting device according to another embodiment of the present invention.
4 is a longitudinal sectional view of the rotation balance correcting device in a state where the rotation balance correcting device of FIG. 3 is mounted on an information recording medium.
5 is a longitudinal sectional view showing another example of the shape of the inner surface of the hollow portion in FIGS. 1 and 4. FIG.
[Explanation of symbols]
1 Motor 2 Turntable 3 Disc Information Recording Medium (Disc)
4,7 Balancer for disc-shaped information recording media (balancer)
DESCRIPTION OF SYMBOLS 5 Clamper 6 Disk drive device 41 Circular recessed part 42 Disk-shaped part 43,71,81 Hollow path 431 Enclosed part 432 Lid member 44 Outer peripheral part 45,73,82 Sphere 72 Ring member 74 Annular groove 75 Sphere entrance 83 Arc-shaped part

Claims (5)

In a rotation balance correction device that automatically adjusts the weight imbalance of a disk-shaped information recording medium during rotation,
A disk-shaped part having at least the same diameter as the disk-shaped information recording medium;
An outer peripheral portion provided around the outer peripheral end of the disk-shaped portion, and having an annular hollow path therein;
A plurality of spheres movable in the hollow path;
With
The rotation balance correcting device according to claim 1, wherein the outer peripheral portion is located radially outside the disc-shaped information recording medium . The rotation balance correcting device according to claim 1, wherein the disk-shaped portion has a circular recess into which an outer peripheral portion of the disc-shaped information recording medium can be fitted. The outer peripheral portion includes a surrounding bending portion that is extended from a peripheral end of the disk-shaped portion and has an upper surface opened, and an annular lid that covers the upper surface of the surrounding bending portion. The rotation balance correction apparatus according to claim 1 or 2. The rotation balance correcting device according to any one of claims 1 to 3, wherein the hollow path has an arc shape in which at least a longitudinal cross-sectional shape on the outer peripheral inner surface side is larger in diameter than the diameter of the sphere. 5. A disk drive device comprising a disk holding surface capable of holding a disk-shaped information recording medium to which the rotation balance correcting device according to claim 1 is attached.

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