JPH10320906A - Imbalance suppressing device for an optical disk apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize suppression of vibration due to imbalance even when there exists an imbalance occurrence factor. SOLUTION: Imbalance detection means 5 is attached to a spindle motor 2, so that a vibration of a disk 3 along a racial direction due to imbalance can be detected. A signal which has a phase opposite to a detected signal due to vibration is outputted to imbalance adjusting means 4 as a suppression signal. Thus, the imbalance adjusting means 4 attached to a chassis 1 causes the chassis 1 to vibrate based on the suppression signal, so as to suppress vibration due to imbalance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an imbalance suppressing apparatus for an optical disc apparatus which suppresses imbalance due to eccentricity of the disc, which becomes a problem with high-speed rotation of the disc.

[0002]

2. Description of the Related Art Conventionally, an optical disc apparatus clamps a disc with a turntable and a clamper to produce a 300-p.
The laser beam is rotated at 700 ppm from pm, and at the same time, a laser beam is condensed by an objective lens and irradiated onto the disk to record and reproduce information.

Since the laser light condensed by the objective lens needs to be irradiated to a predetermined position on the disk, the position of the objective lens is controlled by an objective lens driving device or the like.

[0004] In response to the demand for shortening the recording and reproducing time on a disk, so-called double speed, quadruple speed, eight times speed,
Double-speed optical disk devices have begun to be supplied to the market, and 16-times and 20-times optical disk devices have been researched and developed.

[0005]

However, discs have an imbalance due to eccentricity, printing, etc. inherent to the disc, and imbalance also exists in a spindle motor or the like for rotating the disc. Further, when the disk is clamped, the disk is eccentrically clamped, or the disk being rotated is slipped due to insufficient clamping force of the disk, and the disk is displaced, resulting in an imbalance.

As a result, when the disk is rotated at high speed, imbalance due to these factors occurs, causing the optical disk apparatus to vibrate and sometimes resonate, so that it becomes difficult to irradiate a predetermined position of the disk with laser light. There is.

[0007] Further, it is necessary to increase the thrust of the objective lens driving device with the speeding up of the disk. However, resonance also occurs due to the high speed movement of the objective lens due to the increase in the thrust.

Furthermore, in order to rotate the disk at a high speed, it is necessary to increase the size of the spindle motor to increase the thrust. There is a problem that it is difficult to reduce the power consumption, reduce the resonance, and reduce the power consumption.

It is therefore an object of the present invention to provide an imbalance suppressing apparatus for an optical disk device that can suppress the vibration caused by the imbalance even when the above-described imbalance occurrence factor exists.

[0010]

According to the first aspect of the present invention, there is provided a spindle motor for rotating a disk, a chassis for supporting the spindle motor, and a spindle motor for rotating the disk. And an imbalance detecting means for detecting a vibration caused by the imbalance and outputting a suppression signal, and an imbalance adjusting means for reducing the vibration caused by the imbalance based on the suppression signal from the imbalance detection means. Features.

That is, the imbalance suppressing device is constituted by the imbalance detecting means and the imbalance adjusting means.
Then, the vibration generated by the imbalance is detected by the imbalance detecting means, and the suppression signal is output based on the detection signal. Then, the vibration generated by the imbalance based on the suppression signal is suppressed by the imbalance adjusting means.

According to a second aspect of the present invention, the imbalance detecting means is fixed to the spindle motor to detect radial vibration of the disk due to the imbalance. Then, a signal having a phase opposite to the detection signal due to the vibration is output to the imbalance adjusting unit as a suppression signal. Thereby, the imbalance adjusting means fixed to the chassis causes the chassis to vibrate based on the suppression signal, thereby reducing the vibration due to the imbalance.

According to a third aspect of the present invention, there is provided an imbalance detecting means comprising: a plurality of magnets supported by a holding means via an elastic member; and an imbalance detecting coil fixed to a chassis and generating an induced voltage by the magnets. And an arithmetic means for calculating an imbalance direction and an imbalance amount based on a detection signal from the imbalance detection coil, and outputting the result as a suppression signal. Further, the imbalance adjusting means is constituted by a position control coil that controls the position of the magnet based on the suppression signal to reduce vibration due to the imbalance.

According to a fourth aspect of the present invention, the imbalance detecting means is closely attached at equal intervals to a peripheral surface of a bearing for rotatably supporting the motor shaft of the spindle motor, thereby suppressing radial vibration of the motor shaft due to the imbalance. A plurality of piezoelectric elements detected via a bearing, and an arithmetic means for calculating an imbalance direction and an imbalance amount based on a signal from the piezoelectric elements and outputting the result as a suppression signal. I do.

According to a fifth aspect of the present invention, there is provided an imbalance detecting coil, wherein the imbalance detecting means is fixed to a chassis by an even number of magnets supported by a holding means via an elastic member and generates an induced voltage by the magnet. And calculating means for calculating an imbalance direction and an imbalance amount based on a detection signal from the imbalance detection coil, and outputting the result as a suppression signal. In addition, the imbalance adjusting means generates a magnetic field based on the suppression signal and applies a magnetic force to every other magnet among the even number of magnets, thereby controlling the position of the magnets and reducing vibration due to imbalance. It is characterized by comprising a position control coil.

According to a sixth aspect of the present invention, there is provided a balancer comprising a plurality of magnets provided at equal intervals on a holding means and having an imbalance detecting means, and an intermediate part between the adjacent balancers supported by the holding means via an elastic member. An imbalance detection magnet composed of a plurality of magnets, an imbalance detection coil fixed to a chassis and generating an induced voltage by at least the imbalance detection magnet, and a detection signal from the imbalance detection coil. A calculating means for calculating the imbalance direction and the imbalance amount and outputting the result as a suppression signal. Also, the imbalance adjusting means has one end fixed to the balancer and the other end fixed to the holding member, and expands and contracts based on the suppression signal, thereby controlling the position of the balancer to reduce vibration due to imbalance. It is characterized by comprising.

According to a seventh aspect of the present invention, the imbalance suppressing device includes an imbalance detecting unit and an imbalance adjusting unit. The imbalance detecting means is fixed to the spindle motor, detects the vertical vibration of the disk surface, and outputs a signal having a phase opposite to a detection signal due to the vibration as a suppression signal. Further, the imbalance adjusting means is fixed to the chassis, and the chassis is vibrated based on the suppression signal, so that the vibration due to the imbalance is reduced.

According to an eighth aspect of the present invention, the imbalance detecting means is constituted by a piezoelectric element disposed at the lower end of the motor shaft of the spindle motor and for directly detecting the axial vibration of the motor shaft due to the imbalance. Features.

According to a ninth aspect of the present invention, when information is recorded on a disk rotating at a high speed, and when the recorded information is read out, a printed pattern on the surface opposite to the recording surface of the disk is generated. In order to reduce imbalance due to imbalance, the density of ink used for printing the print pattern is adjusted.

According to a tenth aspect of the present invention, when information is recorded on a disk rotating at high speed, and when the recorded information is read out, a printed pattern on the surface opposite to the recording surface of the disk is generated. In order to reduce imbalance due to imbalance, the disk is provided with a balancer.

According to an eleventh aspect of the present invention, the balancer comprises:
It is characterized by being any one of ink, ultraviolet curable resin and seal.

According to a twelfth aspect of the present invention, the balancer comprises:
The disk is characterized by being inserted into a center hole of the disk and capable of adjusting the position in the radial direction of the disk.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic perspective view of an optical disk device provided with an imbalance suppressing device applied to the description of the present embodiment.

The optical disk device includes a turntable 7 as a holding means and a clamper (not shown). The spindle motor 2 clamps and rotates the disk 3 by using them, and irradiates the disk 3 rotating at high speed with laser light. An optical pickup 6 for recording or reproducing information on or from a disk 3, a spindle motor 2, and a chassis 1 on which the optical pickup 6 is mounted. The optical pickup 6 is mounted on a side surface of the spindle motor 2. Imbalance detecting means 5 for detecting the radial vibration of the disc accompanying the imbalance adjusting means 4 for applying vibration based on a signal from the imbalance detecting means 5 so as to cancel the vibration. .

The imbalance detecting means 5 is provided so as to detect the vibration of the optical pickup 6 in the seek direction (radial direction), and the imbalance adjusting means 4 does not transmit the radial vibration to the optical pickup 6. As described above, the vibration of the opposite phase is applied to cancel the vibration.

The position of the imbalance adjusting means 4 is preferably arranged on a line connecting the optical pickup 6 and the spindle motor 2, but the present invention is not limited to this.

Radial vibrations of the disk 3 and the spindle motor 2 rotating at high speed are detected by the imbalance detecting means 5. Then, a signal having a phase opposite to that of the detected vibration is output to the imbalance adjusting unit 4 as a suppression signal in order to cause the imbalance adjusting unit 4 to generate a vibration having a phase opposite to the detected vibration. Imbalance adjustment means 4
Vibrates the chassis 1 based on the opposite phase suppression signal.

As a result, the vibration in the radial direction due to the rotation of the disk 3 and the spindle motor 2 is canceled, and the vibration of the optical pickup 6 and the like mounted on the chassis 1 can be reduced.

Therefore, the objective lens 8 provided in the optical pickup 6 can accurately follow the signal groove (track) of the disk 3, and the reliability of data recording / reproduction is improved.

Further, even if a disc 3 that does not satisfy the eccentricity standard is set in the optical disc apparatus according to the present invention and imbalance occurs due to high-speed rotation of the disc 3, the imbalance can be canceled. become able to.

Further, even when the disk 3 slips and shifts position during rotation of the disk 3 and imbalance occurs as a result, the imbalance is always suppressed so that the imbalance is suppressed. It becomes possible to deal with the situation.

Next, a second embodiment of the present invention will be described with reference to the drawings. Note that the same components as those of the first embodiment are denoted by the same reference numerals and description thereof will be omitted as appropriate.

FIGS. 2 and 3 show the structure of the imbalance detecting means and the imbalance adjusting means according to this embodiment. FIG. 2 shows the lower surface of the turntable (the surface on which the disk is mounted is referred to as the upper surface). 3 (a) is a sectional view thereof, and FIG. 3 (b) is an enlarged view of a region A in FIG. 3 (a).

The imbalance detecting means includes an elastic member 9 (9a, 9b, 9) fixed to the lower portion of the turntable 7.
c), a magnet 10 (10a, 10b, 1) attached to the tip of the elastic member 9 and displaceable in the radial direction.
0c), an imbalance detection coil 12 and the like are fixed to an angle 13 provided on the chassis 1 below the turntable 7 and arranged so that the coil surface faces the axial direction of the turntable 7.

The imbalance adjusting means is fixed to the lower part of the turntable 7 and has a coil surface which is fixed to the magnet 1.
0 of the position control coil 11 (11
a, 11b, 11c), an imbalance direction and an imbalance amount are calculated from a signal (induction voltage) from the imbalance detection coil 12, and a suppression signal (not shown) is output to the position control coil 11 based on the calculation result. Means.

The case where three magnets 10 and three position control coils 11 are provided at equal intervals is shown, but the number is not limited to three, as will be apparent from the following description. .

In such a configuration, when there is no imbalance in the turntable 7 or the like, each magnet 10 is displaced by the same amount due to centrifugal force due to the rotation of the turntable 7.
However, when an imbalance occurs due to the eccentricity of the disk 3 or the imbalance of the turntable 7 itself, the displacement amount of each magnet 10 becomes different corresponding to the imbalance.

Generally, when the magnetic flux density interlinking a coil changes, an induced electromotive force is generated in the coil. Also,
The magnetic flux density attenuates in inverse proportion to the square of the distance from the magnet. Therefore, when the displacement of the magnet 10 changes due to the imbalance, the distance between the magnet 10 and the imbalance detection coil 12 changes, so that the induced voltage induced in the imbalance detection coil 12 changes depending on the displacement. become.

This will be described in detail with reference to FIG. FIG. 4A shows the displacement of the magnet 10 when such imbalance occurs, and FIG. 4B shows the change in the induced voltage induced in the imbalance detection coil 12 at that time. .

In FIG. 4A, the description will be made on the assumption that the turntable 7 is rotating counterclockwise and that an imbalance is generated in the direction of the magnet 10a.

In FIG. 4A, the equilibrium position of each magnet when rotated at high speed in an ideal state without imbalance is indicated by a dotted line (denoted as magnets 10a ', 10b' and 10c '). The equilibrium position of each magnet when rotating at a high speed in a certain state is shown by a solid line (described as magnets 10a, 10b, and 10c).

When the imbalance according to the above definition occurs, the magnets 10b and 10c are displaced from the magnets 10b 'and 10c' toward the axis of the turntable 7, and the magnet 10a is positioned outside the magnet 10a '.

Since the magnet 10 scans the front surface of the imbalance detection coil 12, an induced voltage is generated in the imbalance detection coil 12, and the magnet 10 a passes closest to the imbalance detection coil 12. , The induced voltage becomes maximum, and a waveform of the induced voltage as shown in FIG. 4B is obtained. Note that reference numerals a, b, and c in FIG.
Indicates that the voltage is induced by the magnets 10a, 10b, and 10c.

Therefore, the arithmetic means calculates the imbalance direction and the imbalance amount based on the peak value of the induced voltage, and outputs a suppression signal to the position control coil 11 so as to suppress the imbalance based on the calculation result. . The position control coil 11 generates a magnetic field based on the suppression signal.

As shown in FIG. 5, the magnet 10 receives a force depending on the strength and direction of the magnetic field generated in the position control coil 11.

Therefore, for example, when imbalance occurs in the direction of centrifugal force, the imbalance by the turntable 7 or the like is output by outputting a suppression signal so as to reduce the displacement of the magnet 10a. It becomes possible to suppress.

The suppression of the imbalance is achieved by the disk 3
Is performed when the disk 3 is set on the turntable 7 and rotation is started. However, it goes without saying that the disk 3 may be rotating.

In the above description, the position control coil 11
Are provided on both sides of the magnet 10, but the present invention is not limited to this. For example, as shown in FIG. 6, the magnet 10 can be provided on the rear side (the shaft core side of the turntable 7). It is.

Next, a third embodiment of the present invention will be described with reference to the drawings. Note that the same reference numerals are used for the same components in the above embodiments, and the description will be appropriately omitted.

FIG. 7A is a detailed sectional view of the turntable 7 of the optical disk device according to the present embodiment, and FIG. 7B is a perspective view showing a main part thereof.

Usually, the motor shaft 16 of the spindle motor 2
Is supported by a bearing 14 housed in a housing 17 or the like. Therefore, when an imbalance occurs due to the disk 3, the turntable 7, and the like, the imbalance is transmitted to the housing 17 via the bearing 14.

Therefore, in this embodiment, the imbalance detecting means is replaced by a plurality of piezoelectric elements 15 (15a, 15b, 15b).
c), and are arranged at equal intervals between the housing 17 and the bearing 14.

Thus, the radial force applied to the motor shaft 16 due to the imbalance is detected by the piezoelectric element 15, and the imbalance direction and the imbalance are calculated by the calculating means based on the voltage difference resulting from the difference in the force applied to each piezoelectric element 15. The balance amount is calculated and a suppression signal is output.

Then, based on the suppression signal, the position of the magnet 10 is controlled, for example, as in the first embodiment, to suppress the imbalance.

In this case, since the magnet 10 is used only as a balancer, it does not need to be a magnet, and may be a magnet (for example, a magnetic material such as iron) which receives a magnetic force by a magnetic field generated by the position control coil 11. I just need.

It goes without saying that the number of piezoelectric elements 15 is not limited to three.

Next, a fourth embodiment of the present invention will be described with reference to the drawings. Note that the same reference numerals are used for the same components in the above embodiments, and the description will be appropriately omitted.

FIG. 8A is a diagram showing the configuration of the imbalance detecting means and the imbalance adjusting means in the optical disk device according to the present embodiment.

The imbalance detecting means includes a plurality of magnets 10 (10) supported by an elastic member 9 fixed to a lower portion of the turntable 7 and provided so as to be displaceable in the radial direction.
a, 10b, 10c), and has an imbalance detection coil 12 fixed to the chassis 1 below the turntable 7 and detecting the magnetic flux of the magnet 10.

The imbalance adjusting means includes an elastic member 18 (18a, 18b, 1) between the adjacent magnets 10.
8c) supported by the balancer 20 (20a, 20b, 2)
0c), a position control coil 11 (11a, 11b, 11c) for controlling the position of the balancer 20, an arithmetic unit (not shown), and the like.

The balancer 20 does not need to be a magnet, but the present embodiment will explain a case where a magnet is used.

A method for detecting imbalance and suppressing the imbalance will be described with reference to FIGS. 8B and 8C. FIG.
FIG. 8B is a diagram schematically showing an imbalanced state.
(C) is a diagram showing an induced voltage induced in the coil by the magnet.

For convenience of explanation, it is assumed that the eccentricity occurs in the direction of the centrifugal force of the magnet 10a, and the solid line in FIG. 8B indicates the position of each magnet when there is no imbalance.
The dotted line shows the position of each magnet when there is imbalance.

In such an imbalance state,
An induced voltage as shown in FIG. 8C is induced in the imbalance detection coil 12, and the magnet 10 a comes closest to the imbalance detection coil 12 and thus has the largest peak value. The sign at the peak value indicates that the voltage is induced by the corresponding magnet or the like.

Therefore, the imbalance direction and the amount of imbalance are calculated by the calculating means from the peak value of the induced voltage by each magnet, and a suppression signal is output to the position control coil 11 to suppress the imbalance.

By controlling the position of the balancer 20, the imbalance caused by the turntable 7, the disk 3, and the like is reduced, and the magnet 10 supported by the elastic member 9 is moved to the new equilibrium position. Therefore, fine imbalance can be suppressed.

In the above description, the position adjustment of the balancer 20 is performed by the position adjustment coil 11, but as shown in FIG. 9, the piezo elements 23 (23a,
3b, 23c) and the like.

When the piezo element 23 is used, the position of the balancer 20 can be adjusted very precisely and at high speed. In addition, since the piezo element 23 mechanically regulates the position of the balancer 20, it can be externally controlled. There is an advantage that the position of the balancer 20 does not change even when pulse vibration is applied.

Next, a fifth embodiment of the present invention will be described with reference to the drawings. Note that the same reference numerals are used for the same components in the above embodiments, and the description will be appropriately omitted.

In each of the embodiments described above, it is assumed that the imbalance occurs in a direction parallel to the disk surface. However, in practice, the imbalance occurs in a direction perpendicular to the disk surface, that is, the focusing direction of the objective lens. Also occurs. In the present embodiment, the imbalance in the focusing direction is suppressed.

FIG. 10 is a schematic perspective view of an optical disk device according to the present embodiment. The optical disk device includes a turntable 7 as a holding means and a clamper (not shown), and clamps and rotates the disk 3 by these. A spindle motor 2 for rotating the disk 3, a high-speed rotating disk 3, and an optical pickup 6 for recording or reproducing information on the disk 3 by irradiating a laser beam to the disk 3, a chassis 1, on which the optical pickup 6 is mounted, and a spindle motor Imbalance detecting means 25, which is attached to the side surface of the motor 2 and detects a vibration caused by imbalance of the spindle motor 2 and the disk 3 in a direction perpendicular to the disk surface and outputs a suppression signal;
5 has an imbalance adjusting means 24 acting to cancel the vibration based on the suppression signal from the control unit 5.

The imbalance detecting means 25 detects a vibration due to the imbalance of the optical pickup 6 in the focusing direction, and outputs a signal having a phase opposite to that of the vibration as a suppression signal. The imbalance adjusting unit 24 applies vibration to the chassis 1 based on the suppression signal so as to attenuate the vibration.

The position of the imbalance adjusting means 24 is preferably arranged on a line connecting the optical pickup 6 and the spindle motor 2, but the present invention is not limited to this.

As a result, the vibration due to the imbalance in the focusing direction due to the rotation of the disk 3 and the spindle motor 2 is canceled, and the vibration of the optical pickup 6 mounted on the chassis 1 can be suppressed.

Therefore, the laser spot condensed by the objective lens can always be converged on the recording layer of the disc 3, and stable information recording and reproduction can be performed.

Next, a sixth embodiment of the present invention will be described with reference to the drawings. Note that the same reference numerals are used for the same components in the above embodiments, and the description will be appropriately omitted.

In the fifth embodiment, the vibration caused by the imbalance in the focusing direction is detected by the imbalance detecting means 25 provided on the side of the spindle motor 2. The motor is directly detected from the motor shaft.

As shown in FIG. 11, a thrust bearing 27 is provided below the motor shaft 28, and a piezoelectric element 26 is provided between the thrust bearing 27 and the housing 29 of the spindle motor 2.
Is arranged.

With the above configuration, the disk 3 rotating at a high speed
Vibration in the focus direction caused by imbalance caused by the spindle motor 2 or the like can be directly detected by the piezoelectric element 26.

Then, a signal having a phase opposite to that of the detected signal is output as a suppression signal to, for example, the imbalance adjusting means 24 according to the fifth embodiment so as to suppress the vibration in the focus direction.

Thus, the laser spot focused by the objective lens can always be focused on the recording layer of the disk 3, and stable recording and reproduction of information can be performed.

In particular, since the piezoelectric element 26 serving as the imbalance detecting means is disposed inside the spindle motor 2, the handling becomes easy and the size of the apparatus can be reduced.

Next, a seventh embodiment of the present invention will be described with reference to the drawings. In each of the embodiments described so far, the vibration due to the imbalance in the radial direction and the focusing direction due to the eccentricity of the disk is detected and the vibration is suppressed. This is to improve imbalance due to printing or the like, which is one of the causes of balance.

Various colorful designs (printed patterns) are printed on the disc. Due to differences in the layout and the like in the plane of the designs and differences in the density due to the colors of the printing inks used in the designs and the like. Imbalance is occurring.

For example, as shown in FIG. 12, patterns A, B, and C having different print patterns are formed on the surface opposite to the recording surface of the disk.
Is formed, when the disk 3 is rotated, imbalance due to printing causes imbalance, causing resonance or the like, and the disk 3 cannot be rotated at high speed.

Therefore, even if each printing pattern is different, the density of the printing ink for each printing is adjusted so that imbalance does not occur when the disk 3 is rotated, and printing is performed so that the disk 3 can be imbalanced. Do.

As a method of adjusting the density, it is possible to add a fine powder transparent member to the printing ink or to increase the thickness of the printing.

If the densities of the printing inks are different, the degree of freedom in design such as the printing area, printing position, and printing shape is widened, and the imbalance can be reduced.

In order to remove the imbalance,
As shown in FIG. 13, a transparent ink, a transparent ultraviolet curing resin, a transparent seal, or the like may be applied or affixed as the balancer 30.

Such a balancer 30 is particularly effective when the design is printed on one side of the disk 3. This is because, in such a case, the imbalance cannot be eliminated even if the density of the printing ink is adjusted.

Next, an eighth embodiment of the present invention will be described with reference to the drawings. FIG. 14 is a sectional perspective view of the disk 3. The center of the disk 3 is provided with a center hole 40 that fits into the turntable 7 or the like.

Therefore, in the present embodiment, the center hole 4
The balancer 31 such as a thin metal or a mold is sandwiched from above and below from above and below to suppress imbalance.

The balancer 31 has a plurality of adjustment holes 32.
Is formed, and an adjustment hole 3 is formed around the center hole 40 of the disk.
2, a pin hole 33 having a smaller diameter than the adjustment hole 32.
Is provided.

The body 35 inserted into the adjustment hole 32
Further, an imbalance adjustment driver 37 including a pin 36 provided at a non-center of the front end surface is prepared.

With such a configuration, the pin 36 of the imbalance adjustment driver 37 is inserted into the pin hole 33, and the body 35 is inserted into the adjustment hole 32. Then, the imbalance adjusting driver 37 is rotated to adjust the radial position of the balancer 31 so that imbalance does not occur.

As described above, it is possible to suppress imbalance due to imbalance due to printing of the disk 3 or the like.

In particular, abrasion of the center hole of the disk 3 due to the chucking of the disk 3 and the slip of the turntable 7 and the disk 3 can be reduced, and the disk 3 can be chucked with high accuracy, so that higher speed rotation is possible.

Note that the present invention is not limited to the above configuration, and may have a configuration as shown in FIG. 15, for example. In the figure, an adjustment member 38 instead of the above-described imbalance adjustment driver 37 is inserted into the adjustment hole 32 and the pin hole 33 so that the head is substantially flush with the balancer 31. .

Therefore, the position of the balancer 31 can be adjusted by rotating the adjustment member 38.

[0100]

As described above, according to the present invention, the vibration generated by the imbalance is detected by the imbalance detecting means, and the vibration is suppressed by the imbalance adjusting means. Even if an imbalance exists in the radial direction and the direction perpendicular to the disk surface, it is possible to prevent the disk, the optical pickup, and the like from vibrating, thereby improving the reliability of data recording and reproduction.

Further, by forming the imbalance detecting means by a piezoelectric element, a piezo element, or the like, the apparatus can be made compact, and the imbalance can be suppressed with high accuracy and at high speed.

Further, since the densities of the printing inks are made different, the degree of freedom of the printing area, the printing position, etc. is increased, and the imbalance can be reduced.

Further, since the balancer is provided so as to suppress the imbalance of the disk, it is possible to suppress the occurrence of imbalance due to the disk.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of an optical disc device including an imbalance suppressing device applied to the description of a first embodiment.

FIG. 2 is a main part configuration diagram of an imbalance suppressing device applied to the description of a second embodiment.

FIG. 3 is a sectional view of FIG. 2;

FIG. 4 is a diagram illustrating the operation of the imbalance suppressing device shown in FIG.

FIG. 5 is a diagram illustrating the operation of the imbalance suppressing device shown in FIG. 2;

FIG. 6 is a diagram illustrating another configuration of the imbalance suppressing device illustrated in FIG. 2;

FIG. 7 is a main part configuration diagram of an imbalance suppressing device applied to the description of a third embodiment.

FIG. 8 is a main part configuration diagram of an imbalance suppression device applied to the description of a fourth embodiment;

9 is a diagram showing another configuration of the imbalance suppressing device shown in FIG.

FIG. 10 is a schematic perspective view of an optical disc device provided with an imbalance suppressing device applied to the description of the fifth embodiment.

FIG. 11 is a main part configuration diagram of an imbalance suppressing device applied to the description of a sixth embodiment;

FIG. 12 is a main part configuration diagram of an imbalance suppressing device applied to the description of a seventh embodiment;

13 is a diagram showing another configuration of the imbalance suppressing device shown in FIG.

FIG. 14 is a main part configuration diagram of an imbalance suppressing device applied to the description of the eighth embodiment;

FIG. 15 is a diagram illustrating another configuration of the imbalance suppressing device illustrated in FIG. 14;

[Explanation of symbols]

Reference Signs List 1 chassis 2 spindle motor 3 disk 4, 24 imbalance adjustment means 5, 25 imbalance detection means 6 optical pickup 7 turntable 8 objective lens 9 (9a, 9b, 9c) elastic member 10 (10a, 10b, 10c) magnet 11 (11a, 11b, 11c) Position control coil 12 Imbalance detection coil 13 Angle 14 Bearing 15, 26 Piezoelectric element 16, 28 Motor shaft 17, 29 Housing 20 (20a, 20b, 20c), 30, 31 Balancer 23 (23a, 23a) 23b, 23c) Piezo element 27 Thrust bearing 32 Adjustment hole 33 Pin hole 35 Body 36 Pin 37 Imbalance adjustment driver 38 Adjustment member 40 Center hole

Claims (12)

[Claims] 1. A storage device for holding a disk, comprising:
A spindle motor for rotating the disk, a chassis supporting the spindle motor, imbalance detection means for detecting vibration due to imbalance and outputting a suppression signal when the spindle motor rotates, and the imbalance detection means An imbalance adjusting unit for reducing vibration due to the imbalance based on a suppression signal from the optical disc apparatus. 2. The apparatus according to claim 1, wherein said imbalance detecting means is fixed to said spindle motor to detect radial vibration of said disk due to imbalance.
A signal having a phase opposite to the detection signal due to the vibration is output as a suppression signal, and the imbalance adjusting unit is fixed to the chassis, and vibrates the chassis based on the suppression signal from the imbalance detection unit, and 2. The apparatus according to claim 1, wherein vibration due to balance is reduced. 3. An imbalance detecting means, comprising: a plurality of magnets supported on the holding means via an elastic member; an imbalance detecting coil fixed to the chassis for generating an induced voltage by the magnets; Calculating means for calculating the imbalance direction and the imbalance amount based on the detection signal from the imbalance detection coil, and outputting the result as a suppression signal; 2. The apparatus according to claim 1, further comprising a position control coil that controls a position of the magnet to reduce vibration due to the imbalance. 4. The imbalance detecting means is closely attached at equal intervals to a peripheral surface of a bearing rotatably supporting a motor shaft of the spindle motor, and detects radial vibration of the motor shaft due to imbalance. 2. The optical disk according to claim 1, further comprising: a plurality of piezoelectric elements; and an arithmetic unit that calculates an imbalance direction and an imbalance amount based on a signal from the piezoelectric elements, and outputs the result as a suppression signal. Equipment imbalance suppression device. 5. An imbalance detection means, comprising: an even number of magnets supported by the holding means via an elastic member; an imbalance detection coil fixed to the chassis to generate an induced voltage by the magnets; Calculating means for calculating an imbalance direction and an imbalance amount based on a detection signal from the imbalance detection coil and outputting the result as a suppression signal;
A position control coil that generates a magnetic field based on the suppression signal and applies a magnetic force to every other magnet among the even number of magnets, thereby controlling the position of the magnets and reducing vibration due to imbalance. 2. The apparatus for suppressing imbalance of an optical disk device according to claim 1, wherein: 6. An imbalance detecting means, comprising: a balancer comprising a plurality of magnets provided at equal intervals on the holding means; and an intermediate member supported by the holding means via an elastic member and disposed between the adjacent balancers. An imbalance detection magnet comprising a plurality of provided magnets, an imbalance detection coil fixed to the chassis and generating an induced voltage at least by the imbalance detection magnet, and a detection signal from the imbalance detection coil. Calculating means for calculating the imbalance direction and imbalance amount and outputting the result as a suppression signal, wherein the imbalance adjusting means has one end fixed to the balancer and the other end fixed to the holding member. Then, the position of the balancer is controlled by expanding and contracting based on the suppression signal to reduce vibration due to imbalance. 2. The apparatus according to claim 1, further comprising a piezo element. 7. The imbalance adjustment means, wherein the imbalance detection means is fixed to the spindle motor, detects a vertical vibration of the disk surface, and outputs a suppression signal having a phase opposite to a detection signal due to the vibration, thereby controlling the imbalance adjustment. 2. The apparatus according to claim 1, wherein the means is fixed to the chassis and vibrates the chassis based on the suppression signal to reduce vibration due to imbalance. 8. The apparatus according to claim 1, wherein the imbalance detecting means includes a piezoelectric element disposed at a lower end of the motor shaft of the spindle motor and detecting an axial vibration of the motor shaft due to the imbalance. Item 2. An imbalance suppressing device for an optical disk device according to Item 1. 9. When information is recorded on a disk rotating at high speed and when the recorded information is read, imbalance due to imbalance of the disk caused by a print pattern on the surface opposite to the recording surface of the disk is determined. An imbalance suppressing device for an optical disk device, wherein the density of ink used for printing the print pattern is adjusted to reduce the density. 10. When information is recorded on a disk that rotates at high speed, and when the recorded information is read, imbalance due to imbalance of the disk caused by a print pattern on the surface opposite to the recording surface of the disk is determined. An imbalance suppressing device for an optical disk device, wherein a balancer is provided on the disk to reduce the amount. 11. The apparatus according to claim 10, wherein the balancer is one of an ink, an ultraviolet curable resin, and a seal. 12. The optical disk apparatus according to claim 10, wherein the balancer is inserted into a center hole of the disk and is provided so as to be adjustable in position in a radial direction of the disk. apparatus.