JP2003059147A - Clamping device and motor provided with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a clamping device which can reduce disk holding defects and to provide a motor provided with the device. SOLUTION: In the clamping device C1 freely attachably and detachably holding a recording disk D by placing the recording disk D on a turntable 12 and making a clamper 14 press it with a magnetic attraction force, a table side permanent magnet 20 provided for operating that magnetic attraction force is attached to be allowed to abut on the surface of the turn table 12 opposite to the recording disk placing surface. Thus, the table side permanent magnet 20 can be highly accurately attached to the turntable.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a CD-ROM, a D
The present invention relates to a clamp device that detachably holds a removable recording disk such as a VD, MO, or FD, and a motor including the clamp device.
In particular, it relates to a configuration in which a recording disk is held by a magnetic attraction force.

[0002]

2. Description of the Related Art Usually, CD-ROM, DVD, MO, F
Detachable recording discs such as D (hereinafter simply referred to as discs) are used by mounting them on an information reproducing device for reproducing recorded information, and various discs are used by being replaced according to the information to be reproduced. (Also, some have the ability to write information to the disc). The mounted disk is mounted on a disk drive motor in the device and rotates at high speed. The disk drive motor is equipped with a clamp device that detachably holds the disk.

As a conventional clamp device used for CD-ROM and DVD, for example, the one shown in FIG. 5 is known. FIG. 5 shows a clamp device C and a motor M having the same.
Clamping device C showing half divided based on the rotation axis of
Is a sectional view and the motor M is a side view. In FIG. 4, the motor M is provided in a base B attached to a housing of an information reproducing device (not shown), and the rotary shaft 10 projects upward.

The clamp device C is fixed to the rotary shaft 10 and has a substantially disk-shaped turntable 12 for mounting the disc D, and the clamp device C descends from the information reproducing device to press the upper surface of the mounted disc D. It is composed of a clamper 14, and the disc D is sandwiched and held by the turntable 12 and the clamper 14.

The turntable 12 is made of a non-magnetic material (for example, brass), and has an annular disk mounting portion 12a and a boss portion 12b protruding in the center. Disk mount 1
A rubber member 16 is attached to the outer peripheral portion of the upper surface of 2a for stably supporting the disk D so as not to slip. The boss portion 12b includes an outer peripheral surface 12b1 having substantially the same outer diameter as the inner diameter of the center hole of the disk D, an inclined surface 12b2 that is reduced in diameter by a predetermined range from the upper end of the outer peripheral surface 12b1, and an inclined surface 12b2. Horizontal plane 12b extending horizontally from the upper end
3, the horizontal plane 12b3 is further provided with an annular recess 12c which is open to the clamper 14 side or the disc mounting surface side.

An annular magnetic plate 18 and a permanent magnet 20 are housed in the annular recess 12c, and the magnetic material 18 abuts on the bottom surface of the annular recess 12c.
0 contacts and both members 18 and 20 are fixed in a laminated form. The permanent magnet 20 serves to magnetically attract the clamper 14 described later, and the magnetic plate 18 serves to enhance the magnetic force of the permanent magnet 20. A method of fixing the magnetic plate 18 and the permanent magnet 20 to the annular recess 12c is, for example,
When the contact surfaces are filled with an adhesive and fixed, or when press-fitted and fixed in the annular recess 12c, the turntable 12 is made of synthetic resin and the permanent magnets 20 of the permanent magnet 20 are provided by locking claws provided in the annular recess 12c. When elastically pressing and fixing the upper surface, when the turntable 12 is made of synthetic resin, and a part of the annular recess 12c is welded to press and fix the upper surface of the permanent magnet 20 (using these together) Is also possible). The inclined surface 12b1 serves as a guide means for guiding the center of the disk D and the center of the turntable 12 so that they are easily aligned when the disk D is mounted on the turntable 12. The magnetic plate 10 may be omitted and only the permanent magnet 20 may be provided.

On the other hand, the clamper 14 has a substantially dish-like shape made of synthetic resin, and comprises a pressing portion for pressing the disk on the outer peripheral portion and a concave portion which is depressed in the center corresponding to the boss portion 12b of the turntable 12. An annular magnetic plate 14a is embedded in the bottom portion of the concave portion at a position facing the permanent magnet 20.

In the operation of the clamp device C, the disk D is mounted on the turntable 12, and the clamper 14 descends until the pressing portion presses the disk D. At this time, the permanent magnet 20 of the turntable 12 is connected to the magnetic plate 1 of the clamper 14.
4a and a constant distance h2 are maintained to magnetically attract the clamper 1
The pressing portion 4 always applies a pressing force for pressing the disk D, and the disk D, the turntable 12 and the clamper 1
4 is integrated and the disc D is firmly turntable 12
Fixed to. Since the clamp device C is included in the motor M, the rotation of the motor M causes the disk D to rotate in the same manner.

Although not shown, as a clamp device different from the above, a magnetic plate is provided on the turntable side and a permanent magnet is provided on the clamper side, respectively, and holds the disc by the magnetic attraction force of both, similarly to the above. Is also known.
Also in this configuration, the magnetic plate is housed in the annular recess provided in the turntable, and the permanent magnet is embedded in the clamper made of synthetic resin.

On the other hand, the clamp device C0 used for MO and FD has a structure in which a turntable 42 is provided on the rotary shaft 10 of the motor M as shown in FIG. Is different from the above holding method, the annular recess 42c provided in the turntable 42 is
The permanent magnet 40 housed in the disk is mounted on the disk D1.
The magnetic portion 44a is magnetically attracted and held.

[0011]

However, in the conventional clamping device, a holding failure may occur in which the disc is not properly attached / detached. As a cause of this,
The clamp device calculates the magnitude of the magnetic attraction force so that the clamper will not come off during rotation and that the clamp will come off easily after stopping. The distance to the opposing magnetic plate and the material of the permanent magnet are set, but in the actual product, the gap h2 between the permanent magnet and the magnetic plate (or the magnetic portion) may not be assembled accurately as designed. can give.

That is, in the clamp device C shown in FIG. 5, the permanent magnet 20 can be magnetically coupled to the turntable 12 even if any of the fixing methods described above is adopted in the annular recess 12c of the turntable 12 together with the magnetic plate 18. The thickness dimension of the plate 18 and the permanent magnet 20 and the deviation when the magnetic plate 18 and the permanent magnet 20 are fixed in the annular recess 12c (the deviation is
When press-fitting or welding, the permanent magnet 20 and the bottom portion 12c1
And a gap formed between the permanent magnet 20 and an adhesive agent, there are many error factors that hinder the positioning of the permanent magnet 20 such as the thickness of the adhesive agent and the like). Has become.

As a result, the stacking thickness h1 is likely to vary, and the upper surface of the permanent magnet 20 is accurately positioned so as to come to a position lower than the lower surface of the magnetic plate 14a, which is a predetermined position, by a predetermined distance (h2). Difficult to install. That is, the stacking thickness h1 affects not only the desired magnetic attraction force for the clamper 14 due to the distance h2 between the permanent magnet 20 and the magnetic plate 14a, but also the pressing force for the disk D. The holding failure of the disk D occurs in the clamp device C.

Also, as described above, the turntable 12
Even if the clamping device does not have the magnetic plate 10 but only the permanent magnet 20, the error factor due to the magnetic plate 10 can be deleted, but other error factors still exist, and the defective holding of the disk D is eliminated. Not a thing. Further, as described above, also in the clamper device in which the magnetic plate is provided on the turntable side, the configuration is substantially the same and the same problem occurs.

Further, in the clamp device C0 shown in FIG.
The permanent magnet 40 has an annular recess 42c of the turntable 42.
Is fixed to the turntable 42,
There are many error factors that hinder the positioning of the permanent magnet 20, such as the thickness of the permanent magnet 40 and the displacement of the annular recess 42c when the permanent magnet 40 is fixed. As a result, the stacking thickness h1 is likely to vary, and the upper surface of the permanent magnet 40 is accurately positioned so as to come to a position that is a predetermined distance (h2) below the lower surface of the magnetic portion 44a of the disk D1, which is a preset predetermined position. Difficult to install. That is, the stacking thickness h1 affects the distance h2 between the permanent magnet 40 and the magnetic portion 44a, so that the magnetic attraction force on the disk D1 cannot be obtained as desired, and also the pressing force on the disk D1 is affected. Clamp device C0
In this case, the holding failure of the disk D1 occurs.

As described above, the conventional clamping device has a structure in which the annular concave portion of the turntable provided for accommodating the permanent magnet or the magnetic plate is formed so as to open toward the clamper side (disk mounting). (A structure that opens on the same surface as the surface)
However, since the permanent magnet or the magnetic plate is abutted and fixed to the disk mounting surface side of the turntable, as a result, it is difficult to assemble the permanent magnet or the magnetic plate of the turntable with high accuracy. is there.

Therefore, the present invention is to solve the above-mentioned problems, and it is an object of the present invention to provide a clamp device and a motor having the same which can reduce defective holding of a disk.

[0018]

In order to solve the above-mentioned problems, a clamping device of the present invention comprises a turntable on which a removable recording disk is mounted, and a recording disk mounted on the turntable from above. In a clamp device including a table-side permanent magnet provided on the turntable that magnetically attracts the clamper-side magnetic material provided on the clamper for pressing, the table-side permanent magnet is
The turntable is fixed so as to come into contact with the surface opposite to the recording disk mounting surface.

Further, the table side magnetic material may be fixed so as to come into contact with the table side permanent magnet.

In such a clamp device, the table-side permanent magnet is positioned and attached by contacting the surface of the turntable opposite to the recording disk mounting surface. As a result, the mounting position of the table-side permanent magnet on the turntable is only an error factor due to the thickness dimension of the turntable and the deviation when the table-side permanent magnet is fixed.
The thickness dimension of the permanent magnet is excluded from the error factor, and the table-side permanent magnet can be positioned and attached to the turntable with high accuracy.

Further, even in the clamp device provided with the table-side magnetic material, since the magnetic material is attached to the place where the table-side permanent magnet has already been attached to the turntable, the attachment position of the permanent magnet is not changed. It does not hinder. Moreover, since the table-side permanent magnet is covered with the table-side magnetic material, not only the magnetic force of the permanent magnet is enhanced, but also the rust-preventing effect of the permanent magnet and the generation of magnetic powder are suppressed.

Another clamping device is a turntable on which a removable recording disc is mounted and a clamper-side permanent magnet provided on a clamper for pressing the recording disc mounted on the turntable from above. And a table-side magnetic material provided on the turntable that is magnetically attracted by the table, the table-side magnetic material being in contact with a surface of the turntable opposite to the recording disk mounting surface. It is characterized by being fixed.

Also in this clamp device, the table side magnetic material is positioned and attached by contacting the surface of the turntable opposite to the recording disk mounting surface. This allows
Regarding the mounting position of the magnetic material on the table side of the turntable, the only error factors are the thickness dimension of the turntable and the deviation when the magnetic material on the table side is fixed, and the thickness dimension of the magnetic material is excluded from the error factors. The magnetic material can be accurately positioned and attached to the turntable.

Further, another clamp device is provided on the turntable for magnetically attracting the turntable on which the removable recording disc is mounted and the magnetic portion provided on the recording disc mounted on the turntable. And a table-side permanent magnet, the table-side permanent magnet is fixed so as to abut on a surface of the turntable opposite to the recording disk mounting surface.

Also in such a clamp device, the permanent magnet on the table side is positioned and attached by contacting the surface of the turntable opposite to the recording disk mounting surface. As a result, the mounting position of the table-side permanent magnet on the turntable is determined by the thickness dimension of the turntable,
Also, only the deviation of the table-side permanent magnet when fixed becomes an error factor, and the thickness dimension of the permanent magnet is excluded from the error factor, and the table-side permanent magnet can be positioned and attached to the turntable with high accuracy.

Further, the turntable may be provided with a concave portion which is opened on the surface opposite to the disk mounting surface for accommodating the table-side permanent magnet or the table-side magnetic material. Thereby, the table-side permanent magnet or the table-side magnetic material is easily fixed.

Further, a resin material may be filled so as to seal the recess. As a result, the table-side permanent magnet or the table-side magnetic material can be firmly fixed to the turntable, and surface treatment for rust prevention,
The permanent magnet does not require surface treatment to prevent the generation of magnetic particles. As described above, in any of the clamp devices, the table-side permanent magnet or the table-side magnetic material in the turntable can be attached with high accuracy, so that the magnetic attraction force with the clamper is set as desired to reduce the disc holding failure. can do.
Further, in the motor equipped with each of the above-mentioned clamp devices, it is possible to reduce defective holding of the disc.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a clamp device and a motor having the same according to the present invention will be described with reference to FIGS. 1 to 3 schematically show half-sections of a clamp device for holding a removable recording disk and a motor having the same, which are similar to those described in the prior art shown in FIG. 5, and FIG. 7 is a schematic view showing a clamp device for holding the same removable disk as described in the related art shown in FIG. 6 and a judgment surface of a motor having the same. Therefore, in the following description of the present embodiment, the description will focus on the parts different from those in FIGS. 5 and 6, and the same reference numerals denote the same parts.

In the clamp device C1 of the first embodiment and the motor M including the same, as shown in FIG. 1, the annular recess 1 formed in the boss portion 12b of the turntable 12 is formed.
The mounting positions of 2c 'and the permanent magnet 20 are different from those in FIG. That is, the outer surface of the boss portion 12b is the same as the outer peripheral surface 12b of FIG.
1 and the inclined surface 12b2, the horizontal surface 12b3 is not opened but is a flat surface, and the annular recess 12c 'is formed by opening the surface opposite to the disk mounting surface of the boss 12b. That is, the annular recess 12 c ′ opens on the surface of the turntable 12 opposite to the surface facing the clamper 14. Along with this, the permanent magnet 20 (table-side permanent magnet) is housed so as to contact the bottom surface of the annular recess 12c ′ of the turntable 12, and the magnetic plate 18 (table-side magnetic material) is provided on the other surface of the permanent magnet 20. Are abutted and fixed. As a method of fixing the permanent magnet 20 and the magnetic plate 18 to the annular recess 12c ', various methods can be applied as in the conventional method.

In such a clamp device C1, the mounting position of the permanent magnet 20 on the turntable 12 is determined by the thickness dimension of the wall thickness d of the bottom portion 12c1 defining the bottom surface of the annular recess 12c 'and when the permanent magnet 20 is fixed. Of the permanent magnet 20 and the bottom portion 1 in the case of press fitting or welding.
2c1 and the gap formed between the 2c1 and the case where an adhesive agent is present, only the thickness of the adhesive agent and the like, which are all formed by fixing) are determined as error factors.

That is, when the permanent magnet 20 is attached, the error due to the thickness dimension of the permanent magnet 20 and the magnetic plate 18 which have the conventional structure and the deviation at the time of fixing them, regardless of which fixing method is used. Factors can be eliminated.

As described above, in the present embodiment, by reducing the conventional error factor, the mounting position of the permanent magnet 20 can be made accurate, and the distance h2 between the permanent magnet 20 and the magnetic plate 14a of the clamper 14 can be reduced. It can be done accurately. Moreover, it does not substantially change the mounting procedure as compared with the conventional configuration, and does not require strict dimensional control of each component, so it does not impair mass productivity or increase cost. . Furthermore, the permanent magnet 20
Has a structure in which the inner wall surface of the annular recess 12c 'and the magnetic plate 18 substantially cover the surface thereof, so that the surface treatment for preventing rust or generating magnetic particles on the surface of the permanent magnet 20 is simplified or unnecessary. can do. At this time, the magnetic plate 1
If the magnetic plate 18 including the permanent magnet 20 is sealed in the annular recess 12c ′ by filling the adhesive from the exposed surface side of the magnetic disk 8, the surface treatment can be further reduced, and the magnetic plate 18 and the permanent plate 18 The magnet 20 can be firmly fixed.

Next, as shown in FIG. 2, the clamp device C2 as a modification of the first embodiment is different in that the magnetic plate 18 provided on the turntable 12 of FIG. 1 is not provided.
Also in such a clamp device C2, the permanent magnet 20
Since the mounting position of can be set with high accuracy without any change from the configuration of FIG. 1, the same effect can be obtained. In this case, the permanent magnet 20 has an annular recess 12c '.
Since it is exposed to the opening side of the, it is desirable to perform a surface treatment for rust prevention and prevention of magnetic powder generation. Instead of performing the surface treatment, as shown by reference numeral 22 in FIG. 2, the exposed surface should be covered. You may make it fill with an adhesive agent and seal in the annular recessed part 12c '.

Next, in the clamp device C3 of the second embodiment and the motor M provided with the same, as shown in FIG.
The annular recess 1 of the turntable 12 for the embodiment of FIG.
2c 'is provided with a magnetic plate 24 (table-side magnetic material),
The difference is that the clamper 14 is provided with a permanent magnet 26 (a permanent magnet on the clamper side). Also in such a clamp device C3, the mounting position of the magnetic plate 24 can be set with high accuracy without any change from the configuration of the above-described embodiment, and therefore, the same effect can be obtained.

Next, in the clamp device C4 of the third embodiment and the motor M equipped with the same, as shown in FIG. 4, the shape of the turntable 42 and the mounting position of the permanent magnet 40 (table-side permanent magnet) are different. To do. That is, the permanent magnet 40
Are fixed so as to contact the surface of the turntable 42 opposite to the disk mounting surface. In such a clamp device C4, the mounting position of the permanent magnet 40 (the magnetic portion 44
The distance h2) between a and the permanent magnet 40 is equal to the turntable 4
The error factor is determined only by the thickness dimension d of the portion of the disk D1 facing the magnetic portion 44a of the disk D2 and the deviation when the permanent magnet 40 is fixed. That is, when the permanent magnet 40 is attached, the error factor, which is the thickness of the permanent magnet 40 and has the conventional configuration, is eliminated. Therefore, also in the present embodiment, as in the above embodiments,
Poor holding of the disc D1 can be reduced. The same applies to the case where the permanent magnet 40 is provided with a magnetic plate to enhance the magnetic force.

As described above, the clamp device C is held by the clamper which is magnetically attracted to the disc mounted on the turntable for the disc such as the CD-ROM and the DVD.
Various embodiments of both 1, C2, C3 and the clamp device C4 for magnetically attracting and holding the disc itself mounted on the turntable for discs such as MO and FD have been variously described, but the scope of the present invention is not limited thereto. It is not limited to these. For example, the turntable 12 is formed of a single member such as brass in the above embodiment, but may be formed of, for example, a synthetic resin, or the disc mounting portion and the boss portion are formed of different members. However, they may be made of different materials such as synthetic resin and metal. In the above embodiment, the turntable 12,
Although 42 is provided on the rotation shaft of the motor M, it can also be applied when the rotor of the motor M functions as a turntable.

[0037]

As described above, in the clamp device according to the first aspect of the present invention, the permanent magnets can be attached with high accuracy by reducing the error factors that hinder the positioning of the table-side permanent magnets as compared with the conventional ones. The magnetic attraction force acting between the magnet and the magnetic material on the clamper side of the clamper and the pressing force of the clamper with respect to the disk can be set accurately. Therefore, in the clamp device of the present invention, it is possible to reduce defective holding of the disk due to the mounting position of the table-side permanent magnet on the turntable.

Further, the clamp device according to claim 2 is
While increasing the magnetic force of the table side permanent magnet,
The anti-corrosion effect of the permanent magnet and the effect of suppressing the generation of magnetic powder can be obtained.

In the clamp device according to the third aspect of the present invention, by reducing the error factor that obstructs the positioning of the table-side magnetic plate as compared with the conventional case, this magnetic plate can be attached with high accuracy, and the table-side magnetic plate and the clamper can be attached. It is possible to accurately set the magnetic attraction force acting between the permanent magnets on the clamper side and the pressing force of the clamper against the disc. Therefore, with this clamp device, it is possible to reduce the holding failure of the disk due to the mounting position of the table-side magnetic material on the turntable.

The clamp device according to claim 4 is
By reducing the error factor that hinders the positioning of the table-side permanent magnet compared to the conventional method, this permanent magnet can be mounted with high accuracy, and the magnetic attraction force that acts between the table-side permanent magnet and the magnetic part of the disk is reduced. It can be set accurately. Therefore, with this clamping device,
It is possible to reduce defective holding of the disk due to the mounting position of the permanent magnet on the table side of the turntable.

Further, the clamp device according to claim 5 is
The table-side permanent magnet or table-side magnetic material is easily fixed.

Further, the clamp device according to claim 6 is
The table-side permanent magnet or table-side magnetic material can be firmly fixed, and surface treatment for rust prevention,
The permanent magnet does not require surface treatment for suppressing magnetic particles.

Further, the motor provided with the clamp device according to the seventh aspect can reduce the number of defective holding of the recording disk.

[Brief description of drawings]

FIG. 1 is a half cross-sectional view showing a first embodiment of a clamp device of the present invention and a motor including the clamp device.

FIG. 2 is a half sectional view showing a modified example of the first embodiment.

FIG. 3 is a half sectional view showing a second embodiment of a clamp device of the present invention and a motor provided with the clamp device.

FIG. 4 is a half sectional view showing a third embodiment of a clamp device of the present invention and a motor provided with the clamp device.

FIG. 5 is a half sectional view of a conventional clamp device and a motor including the same.

FIG. 6 is a half cross-sectional view of another conventional clamp device and a motor including the same.

[Explanation of symbols]

B base C1, C2, C3, C4 clamp device D, D1 disc M motor 10 rotation axis 12,42 turntable 12a Disk mounting part 12b Boss 12c 'annular recess 12c1 bottom 14 Clamper 14a Magnetic plate (magnetic material on clamper side) 18, 24 Magnetic plate (table side magnetic material) 20, 40 Permanent magnet (table side permanent magnet)

Claims (7)

[Claims] 1. A turntable on which a removable recording disk is mounted, and a turn for magnetically attracting a clamper-side magnetic material provided on a clamper for pressing the recording disk mounted on the turntable from above. In a clamping device including a table-side permanent magnet provided on a table, the table-side permanent magnet is fixed so as to come into contact with a surface of the turntable opposite to the recording disk mounting surface. Clamping device. 2. The clamp device according to claim 1, wherein the table-side magnetic material is fixed so as to come into contact with the table-side permanent magnet. 3. A turntable on which a removable recording disk is mounted, and a magnetic disk which is magnetically attracted by a clamper-side permanent magnet provided on a clamper for pressing the recording disk mounted on the turntable from above. A table-side magnetic material provided on the turntable, wherein the table-side magnetic material is fixed so as to abut on a surface of the turntable opposite to the recording disk mounting surface. Characteristic clamp device. 4. A turntable on which a removable recording disc is mounted, and a table-side permanent magnet provided on the turntable for magnetically attracting a magnetic portion provided on the recording disc mounted on the turntable. And a table-side permanent magnet is fixed so as to abut on a surface of the turntable opposite to the recording disk mounting surface. 5. The turntable is provided with a concave portion which is open on a surface opposite to a disk mounting surface in which the table-side permanent magnet or the table-side magnetic material is accommodated. The clamp device according to any one of to 4. 6. The clamp device according to claim 5, wherein a resin material is filled so as to seal the recess. 7. A motor provided with the clamp device according to claim 1.