JP2001012549A - Method and device for vibration control of rotating flat plate body and rotary machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively suppress a vibration occurring on a flat plate body due to flow action of a fluid caused when the flat plate body is rotated in the fluid about a specified axis in the direction of the thickness of the flat plate body. SOLUTION: An annular platy vibration controlling rigid part 28 is formed on the under outside of a pressed annular part 26 of a clamper 20. A vibration occurring on the vibration controlling rigid part 28 at the time of rotating is reduced to a level extremely smaller than that of a CD-ROM36. A flat surface part for access 28a on the underside of the vibration controlling part 28 is formed in an annular flat surface vertical relative to the axis line of the flat part 28. The axial position of the flat surface part for access 28a is approx. 0.3 mm upward from the pressed annular surface of the pressed annular part 26. The outside diameter of the vibration controlling part 28 is set to approx. 2/3 of the radius of the CD-ROM36.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for suppressing vibration generated by the action of a flow of a fluid generated by rotation of a rotating flat plate in a fluid.

[0002]

2. Description of the Related Art A recording disk is an example of a rotating flat plate. However, in recent years, the amount of programs and data for personal computers has increased. For example, a recording disk rotating type recording device such as a CD-ROM drive device shown in FIG. Such a CD-ROM drive device includes a CD-ROM mounted on a turntable c fixed to a rotation shaft b of a drive motor a.
By holding the non-recording portion around the center fitting hole in d between the clamper e and the non-recording portion, the rotational drive of the CD-ROM is ensured.

However, air on the surface of a recording disk such as a CD-ROM and a drive motor is disturbed by the high-speed rotation of the recording disk, and flows toward the outer peripheral side of the recording disk due to centrifugal force. As a result, a pressure difference occurs between the vicinity of the rotation center of the recording disk and the outer peripheral side. In addition, the fluid force (lift, pressure difference between the upper and lower spaces sandwiching the recording disk, etc.) received by the recording disk rotating in air (or other gas) increases more and more, causing the rotating recording disk to vibrate or deform. The "flutter phenomenon" that causes stable reading and writing of data is becoming more serious.

[0004] This flutter phenomenon is that the shape of the flow of air that rotates with the rotation of the disk does not become a perfect circle reflecting the spatial shape of the housing accommodating the recording disk. This is considered to be caused by the pressure difference caused by the vibration and deformation of the disk.

Conventionally, as a countermeasure against this kind of phenomenon, the shape of the air flowing therethrough is made positive by making the space inside the housing accommodating the recording disk symmetrical with respect to the rotation axis of the recording disk. I tried to be a circle. However, important mechanisms such as a read / write means for reading / writing data from / on a recording disk and a control circuit (for example, CD-RO)
When an optical pickup and its driving mechanism are indispensable in the M device, a space for arranging these structures is required, and a completely rotationally symmetric space cannot be created. Even if a completely rotationally symmetrical space can be created, if the recording disk is rotating at a speed higher than a certain level, the upper space with a smaller opening than the space below the recording disk (the space between the recording disk and the housing). It is known that the airflow flowing on the disk surface is not stable between the top plate and the top plate, and this unstable airflow presses the disk to cause flutter. It was not enough.

Although the generation conditions are different from those in the case of the CD-ROM described above, the same problem also occurs in other recording disks or rotating flat bodies (eg, circular saws) other than the recording disks. . The present invention has been made in view of the above-described problems in the related art, and an object thereof is to rotate a target flat body around a constant axis in a thickness direction in a fluid. METHOD AND APPARATUS FOR EFFECTIVELY SUPPRESSING VIBRATIONS GENERATED IN A TARGET PLATE DUE TO ACT OF FLUID FLOW GENERATED BY IT To provide a rotary machine for driving the rotary.

[0007]

Means for Solving the Problems (1) The method for damping a rotating flat plate according to the present invention is characterized in that the flat plate is rotated around a constant axis in its thickness direction in a fluid so as to rotate the flat plate. A method for suppressing mainly vibration in a thickness direction generated in a flat body, wherein a vibration suppression rigid portion having higher rigidity than the target flat body and vibration generated during rotation is smaller than that of the target flat body. In a state where it is opposed to and coaxial with one surface of the plate-shaped body, it is rotated at a speed equal to the rotation speed of the target plate-shaped body, and at least a predetermined amount or more between the opposing vibration suppression rigid portion and the target plate-shaped body. In an annular or circular portion extending over the radial width, the flow of fluid relative to both the vibration-damping rigid portion and the target flat plate is substantially eliminated or reduced to such an extent that the vibration can be suppressed. (Claim 1).

The fluid of interest is generally a gas, especially air.

The target flat body is usually a flat plate having a rotationally symmetric shape, generally, for example, a disk having a rotational axis symmetric shape (including a plate having a through hole at the center position) or an annular plate. Body. Needless to say, a material having some unevenness in the thickness direction may be used. Further, for example, a member supported by another member near the center portion, or a member provided with another member near the center portion may be used. Specific examples include CD-ROM, CD, MO, MD, DVD, DVD
-ROM or RAM, other optical disks, hard disks, FDs, other magnetic disks, other recording disks, and other discs or toroids that are driven to rotate about an axis, especially on one side. All or a fixed radial part (for example, 50%, 60%, 70%, 8% of the radial dimension)
A certain space facing the part of the disc or 90% or more is necessary for performing work such as reading and writing, or the working part is provided on the outer peripheral part (including the side face) of the disk or annular body. Such as those in which a structure is not arranged on at least one side, such as those required.

The rotation axis (constant axis) when the target flat body is driven to rotate is usually the center of gravity line in the thickness direction or a line close thereto.

The vibration in the thickness direction mainly generated in the target flat body by the rotational driving of the target flat body means that the target flat body is in a required environment (for example, narrow in the thickness direction of a required case or the like). In the space, especially in the space asymmetrical about the axis of rotation), the flow of the fluid generated by rotating at the required rotational speed is imbalanced or unstable in the circumferential or radial direction. Means the vibration generated by the action of the fluid flow.

It is preferable that the vibration damping rigid portion has a rotationally symmetric shape, particularly a rotational axis symmetrical shape, and rotates around the axis of symmetry. Specific examples include a disk, an annular plate, a columnar body, and a cylindrical body.

The vibration-damping rigid portion needs to be higher in rigidity than the target flat portion (for example, 1.5 times, 2 times, 3 times, 4 times or 5 times or more). It needs to be smaller than a flat body (for example, less than half, less than one third, less than one quarter, less than one fifth, less than one tenth, less than one twentieth, or less than 50 1/10 or less). In order to increase the rigidity of the disk body or the annular plate body, it is necessary to select a material having a higher rigidity or to increase the thickness as compared with the target flat body, and, for example, to increase the axial direction in the outer peripheral portion. May be provided, a large number of radial or circumferential ribs may be provided in a rotationally symmetric manner, or the thickness may be gradually increased toward the center. Further, in order to reduce the energy required for the rotation of the vibration damping rigid part, it is preferable that the vibration damping rigid part is formed of a lightweight and high rigid material such as aluminum or fiber reinforced plastic. As the material of the vibration damping rigid portion, for example, ceramics, glass, fiber reinforced alloy, other various metals, and the like can be used.

In this method, the rotational speed of the target flat plate is set such that the vibration-damping rigid portion having higher rigidity than the target flat plate is coaxial with one surface of the target flat plate. At a speed equal to or greater than a predetermined radial width (for example, 30%, 40%, 50%, 60% of the radial dimension of the target plate-shaped body) , 70%, 8
Or at least 90% or more of the annular or circular portion, the relative fluid flow to both the vibration-damping rigid portion and the target plate-like body is substantially eliminated or the vibration is suppressed. To the extent that it can be obtained.

[0015] Even during high-speed rotation of the target flat body in the fluid, one surface of the target flat body and the vibration generated during rotation having higher rigidity than the target flat body are smaller than those of the target flat body. Since the relative flow of the fluid in the annular or circular portion over the predetermined radial width between the vibration-damping rigid portions is substantially eliminated or sufficiently reduced, the target flat plate used for performing reading and writing operations, etc. Even if the fluid flow to the other side of the body or the rest of the one side of the target plate is imbalanced or unstable in the circumferential or radial direction, the action of the fluid flow The vibration generated in the target flat body due to the above is effectively suppressed.

(2-1) The method of (1) for damping the rotating flat body is as follows:
The vibration damping rigid portion has an annular or circular approaching planar portion that extends over a predetermined radial width, and the approaching planar portion approaches one side of the target plate-like body and is used for the approach. In a state where the flat portion and the target flat plate are coaxial, the damping rigid portion is rotated at a speed equal to the rotation speed of the target flat plate, and the proximity flat portion of the vibration damping rigid portion and the target flat plate are rotated. In the annular or circular portion extending over the predetermined radial width between them, the fluid flow relative to both the proximity flat portion and the target flat plate of the vibration damping rigid portion rotating at the same speed is substantially eliminated. Or the vibration can be reduced to such an extent that the vibration can be suppressed (claim 2).

The planar portion for proximity is desirably a surface perpendicular to the rotation axis of the vibration-damping rigid portion. However, as long as the vibration damping effect is not impaired, the vibration damping rigid portion may have a portion inclined or uneven with respect to a plane perpendicular to the rotation axis.

The radius of the planar portion for proximity is, for example, 40% or more and 50% or more of the radius of the target plate-shaped member in order to exhibit the vibration damping effect.
60% or more, 70% or more, or 80% or more,
In addition, in order to reduce the power required for rotating the vibration damping rigid portion, the power can be reduced to, for example, 1.2 times or less or 1.1 times or less. Preferably it is 50% or more and 1.1 times or less, more preferably 70% or more and 1 time or less.

It is desirable that the inner peripheral side of the proximity flat portion is closed between the target flat plate and another portion that rotates together with the target flat plate. The width in the direction is sufficient (for example, 5
Or 60%, 60%, 70%, 80% or 90% or more), or if the opening is sufficiently smaller than the plane portion for proximity, it can be opened. .

When the target flat plate is rotated, the gap between one side surface and the flat plate for approximation is set relative to both the flat flat plate for proximity and the target flat plate of the vibration damping rigid portion rotating at the same speed. The flow of the fluid is substantially eliminated or brought close enough to reduce the vibration. The gap in this case can be, for example, about twice or less the thickness of the target flat body. Taking the case of a CD-ROM as an example, it can be set to, for example, 0.3 mm or less.

In this method, the planar portion for proximity of the vibration damping rigid portion is brought close to the target flat plate, and the vibration damping rigid portion is rotated at a speed equal to the rotation speed of the target flat plate. In this respect, there is no danger of damaging or deforming the target flat body because the vibration generated in the body can be effectively suppressed. Can be avoided. Further, if the gap between the planar portion for proximity and the target flat plate is made sufficiently small, vibration generated in the target flat plate can be more effectively suppressed by the effect of the fluid (gas) damper.

(2-2) The method of damping the rotating flat body of (1) and (2-1) can be carried out by the following apparatus.

That is, in the vibration damping device for a rotating flat plate according to the present invention, the object flat plate mainly generates on the target flat plate when the target flat plate is rotated around a constant axis in the thickness direction in the fluid. An apparatus for suppressing vibration in the thickness direction, which has an annular or circular approaching planar portion over a predetermined radial width and has higher rigidity than the target plate-like body, and is a vibration generated at the time of rotation. A vibration-damping rigid portion smaller than the flat plate member, and the vibration-damping rigid portion is formed by moving the approaching planar portion close to one side surface of the target flat plate member and the approaching flat portion and the target flat plate member. Has a constant-speed rotation mechanism that can rotate at the same speed as the rotation speed of the target flat body in a state of being coaxial, and the proximity of the vibration damping rigid portion over a predetermined radial width of the target flat body. Target with the flat part for By damping rigidity portion and the plate-like body is rotated at a rotation speed equal mainly characterized in that the vibration in the thickness direction is suppressed to generate the subject tabular body (claim 3).

According to this vibration damping device, a vibration damping rigid portion that rotates at the same speed in an annular or circular portion over a predetermined radial width between the planar portion for proximity of the vibration damping rigid portion and the target flat plate-shaped body. In the thickness direction mainly generated in the target flat body by substantially eliminating the flow of the fluid relative to both the proximity flat portion and the target flat body or reducing it to such an extent that the vibration can be suppressed. Vibration can be suppressed.

As the same-speed rotation mechanism, for example, the following (2-
In addition to the two holding pressure holding members and the rotation support mechanism described in 3) forming the same speed rotation mechanism, the target flat plate and the vibration damping rigid part are fixed to the rotating body such as the rotating shaft or hub that is driven to rotate. In addition, a component constituting the same speed rotation mechanism can be employed.
Further, the target flat body and the vibration-damping rigid portion (or a member provided with the vibration-damping rigid portion) are coaxially coupled near the center of the target flat body (a disk-shaped recording medium or the like), and the vibration-damping rigidity is reduced. The proximity flat portion of the portion may be housed in a case such as a cartridge case in a state of being close to one side surface of the target flat body.

(2-3) The rotary flat plate vibration damping device of (2-2) is a pair of pressing members capable of holding and releasing the pressing of the central portion of the target flat plate in its thickness direction. And a rotation support mechanism that rotatably supports one or both of the clamping members around an axis in the clamping direction, and one of the clamping members includes:
In the state where the central portion of the target flat body is pressed and held in the thickness direction by the two pressing members, the proximity flat portion which is close to one side surface of the target flat body and is coaxial with the target flat body. One or both of the pressure holding members are supported by a rotation support mechanism and rotated in a state where the central portion of the target flat plate is pressed and held in the thickness direction by the both pressure holding members. Accordingly, the target plate-shaped body and the vibration-damping rigid portion can be rotated at the same rotation speed (claim 4).

The holding of the central portion of the target flat plate by the pair of pressing members is performed, for example, by holding the target flat plate between the two by pressing the two holding members magnetically. This is performed by a suction mechanism, an elastic clamping mechanism that compresses the target flat body by applying a clamping force between both clamping pressure holding members by the elastic force of an elastic member such as a tension spring or a compression spring in the axial direction. be able to.

As one of the two pressing members, for example, a turntable for rotatably supporting the target flat body (a center hole of the target flat body such as a CD-ROM or the like is fitted in the center portion thereof). The one having a center fitting projection for positioning the center position, etc.) can be adopted. As the other pressing member, for example, the vicinity of the center of the target plate-shaped body with the turntable is used. A clamper for clamping can be employed. In addition, the vibration damping rigid portion may be provided on any of the pressing members.

As the rotation support mechanism, for example, one in which one or both clamping members are fixed to a rotatably supported rotating shaft (for example, a rotating shaft of a rotary driving device such as an electric motor) can be cited.

The rotary flat plate vibration damping device may include a rotary drive device (electric motor or the like) for rotating one or both of the pressing members.

(3-1) In the method of (1), the method for damping a rotating flat plate-shaped member is such that a rigid portion capable of blocking a flow of a predetermined fluid is provided on a rigid portion for damping vibration, and one side has a predetermined size or more. The other side of the ring-shaped or circular contact surface extending in the radial direction width is substantially integrated with the vibration damping rigid portion and the flexible portion around a predetermined axis in a direction perpendicular to the contact surface of the flexible portion. When the abutting surface abuts on one side of the target flat body and the abutting surface and the target flat body are coaxial, the vibration damping rigid portion and the flexible The part is rotated substantially integrally at a speed equal to the rotational speed of the target flat body, and an annular or circular shape over a predetermined radial width of the flexible part between the opposing vibration-damping rigid part and the target flat body is formed. In part,
It is possible to substantially eliminate the flow of the fluid relative to both the vibration damping rigid portion and the target plate-like body, or to reduce the vibration to the extent that the vibration can be suppressed (claim 5).

As the flexible portion, for example, felt or sponge-like soft foam resin having elasticity in the thickness direction can be used. It is desirable that the flexible portion should maintain substantially its shape when rotated about the axis in the thickness direction. The thickness of the flexible portion can be, for example, about 1 to 3 mm. Further, the flexible portion can be supported by the vibration damping rigid portion by appropriate means. That is, for example, it can be performed by concentrically bonding the circular surface or the annular surface of the disk-shaped or annular flexible portion to one circular surface of the disk-shaped vibration-damping rigid portion.

The radius of the vibration-damping rigid portion and the flexible portion is, for example, 40% or more, 50% or more, 60% or more, 70% or more, or 80% or more of the radius of the target plate-like body in order to exhibit the vibration-damping effect. In addition, the power can be reduced to, for example, 1.2 times or less or 1.1 times or less in order to reduce the power required for rotation of the vibration suppression rigid portion and the flexible portion. Preferably it is 50% or more and 1.1 times or less, more preferably 70% or more and 1 time or less.

It is desirable that the inner peripheral side of the flexible portion is closed between the target flat plate or another portion which rotates together with the target flat plate, but the flexible portion has a sufficient radial width (for example, 50%, 60%, 70%, 8 of the radial dimension of the target flat plate
(Or part or all of 90% or more) or if the opening is sufficiently smaller than the planar portion for proximity, it can be opened.

When the flexible portion is rotated in the fluid together with the vibration damping rigid portion, the flow of the fluid is substantially prevented between the vibration damping rigid portion and the flexible portion and in the flexible portion.

In this method, the flexible portion supported by the vibration damping rigid portion is brought into contact with the target flat plate, and the vibration damping rigid portion is rotated at a speed equal to the rotation speed of the target flat plate. In this respect, there is no danger of damaging or deforming the target flat body, and the vibration-damping rigid portion and the target flat body can be slammed at this point. It is possible to avoid the phenomenon that the vibration is enlarged. In addition, it is preferable that the contact of the contact surface of the flexible portion with one side surface of the target flat plate is substantially in a non-pressed state. As long as the vibration damping effect is not impaired, there may be a portion where the contact surface does not contact the target flat body.

(3-2) The method for damping the rotating flat body in (1) and (3-1) can be implemented by the following apparatus.

That is, in the vibration damping device for a rotating flat plate according to the present invention, the target flat plate is rotated around a constant axis in the thickness direction of the target flat plate in a fluid to generate the vibration in the target flat plate. A device that mainly suppresses vibration in the thickness direction, wherein the vibration generated at the time of rotation is higher in rigidity than the target plate-like body and a vibration damping rigid part smaller than the target plate-like body,
One side is an annular or circular contact surface over a predetermined radial width and the other side rotates substantially integrally with the vibration damping rigid portion about a predetermined axis in a direction perpendicular to the contact surface. The flexible portion, which is supported by the vibration-damping rigid portion and can block the flow of a predetermined fluid, and the vibration-damping rigid portion and the flexible portion are brought into contact with one side of the target plate-shaped body. A contact-rotating mechanism that can rotate at a speed equal to the rotation speed of the target flat plate in a state where the contact surface and the target flat plate are coaxial with each other, and a predetermined or more than By virtue of the fact that the target flat body and the flexible part rotate at the same rotation speed in a state where the contact surface of the flexible part is in contact with the radial width of the target, vibrations mainly in the thickness direction generated in the target flat body are suppressed. (Claim 6).

According to this vibration damping device, both the vibration-damping rigid portion and the target flat plate-shaped body are formed in an annular or circular portion over a predetermined radial width in the flexible portion between the vibration-damping rigid portion and the target flat plate-shaped body. By substantially eliminating the flow of the fluid relative to the object or reducing the vibration to such an extent that the vibration can be suppressed, it is possible to suppress the vibration mainly in the thickness direction generated in the target flat plate.

As the same-speed rotation mechanism, for example, the following (3-
In addition to the two holding pressure holding members and the rotation support mechanism described in 3) forming the same speed rotation mechanism, the target flat plate and the vibration damping rigid part are fixed to the rotating body such as the rotating shaft or hub that is driven to rotate. In addition, a component constituting the same speed rotation mechanism can be employed.
Further, the target flat body and the vibration-damping rigid portion (or a member having the vibration-damping rigid portion) are coaxially coupled near the center of the target flat body (a disk-shaped recording medium or the like), and the vibration-damping rigid portion is formed. May be accommodated in a case such as a cartridge case in a state where the contact surface of the flexible portion supported by the contact member is in contact with one side surface of the target flat body. (3-3) The vibration damping device for a rotating flat body of (3-2) is a pair of pressing members capable of holding and releasing the pressing of the central portion of the target flat body in the thickness direction thereof, It has a rotation support mechanism that rotatably supports one or both of the pressing members around an axis in the pressing direction, and one of the pressing members is formed of a target plate-like body by the both pressing members. Equipped with a vibration-damping rigid part that supports a flexible part that has an abutment surface that is coaxial with the target flat plate while abutting on the one side surface of the target flat plate while holding the central portion in the thickness direction. When one or both of the pressing members are supported and rotated by a rotation support mechanism in a state where the central portion of the target flat plate is pressed and held in the thickness direction by the two pressing members, the target flat plate body is controlled. The vibration stiffness portions may rotate at the same rotation speed (claim 7).

Matters concerning the pinching member and the rotation support mechanism, and the one in which the rotary flat plate-shaped vibration damping device includes a rotary driving device (an electric motor or the like) for rotating one or both of the pinching members. What can be done is the same as the contents in (2-3).

(4) The rotary machine according to the present invention is a rotary machine for rotating a target flat body in a fluid around a constant axis in a thickness direction thereof, wherein the rotary machine is a rotary machine. The vibration damping device is provided for suppressing mainly the vibration in the thickness direction which is generated in the target flat plate by rotating the target flat plate (claim 8).

The target flat plate is as described above, and is usually a flat plate having a shape to be rotated. Specific examples thereof include various types of recording disks and other discs or toroids that are driven to rotate about an axis.

The rotating machine is for rotating the target flat body. For example, when the target flat body is a recording disk, the rotary machine is provided with a motor for rotating the flat disk or its motor. A recording disk drive, that is, a device or a machine that rotationally drives the target plate-like body can be used.

[0045]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a CD-ROM drive device as an example of a rotary flat plate vibration damping method and a rotary flat plate vibration damping device according to an embodiment of the present invention, and an enlarged view of a main part thereof. (Within a circle).

This CD-ROM drive mainly comprises a drive motor 10 having a vertical rotation axis 10a, a turntable 12 coaxially fixed to the upper end of the rotation axis 10a, and a turntable 12 12 has a clamper 20 disposed above.

The turntable 12 includes a drive motor 10
A rotational axis symmetrical centering on the rotational axis of the upper surface, an upper central portion, an upper portion having a truncated conical surface whose outer diameter is reduced toward the upper side, and a lower portion having a centering projection 12a having a constant outer diameter.
The outer peripheral side of the lower portion has a receiving annular plate portion 12b whose upper surface is perpendicular to the rotation axis 10a line. An annular rubber sheet 12c is provided on the outer peripheral upper surface of the receiving annular plate portion 12b in order to improve the stability of holding a CD-ROM described later. An annular back yoke 16 is arranged below the annular back yoke 16 and an annular clamp magnet 18 is arranged above the annular back yoke 16 in the annular groove 14 having an upper opening provided above the centering projection 12a. The upper surface of the clamp magnet 18 is aligned with the centering projection 12.
a is located slightly below the upper surface.

The clamper 20 disposed above the turntable 12 has a rotational axis symmetrical shape about the vertical axis, and is made of a lightweight and highly rigid non-ferromagnetic material (aluminum, fiber reinforced plastic, etc.). It comprises a clamper body 22 integrally formed and a suction disk portion 24 made of a ferromagnetic material made of an iron-based material. The clamper main body 22 is mainly a CD-R
An OM (to be described later) includes a pressing annular portion 26 for abutting against the inner peripheral portion of the OM and sandwiching the OM between the turntable 12 and a vibration damping rigid portion 28 facing the CD-ROM with a predetermined gap.

Inside the lower part of the clamping ring 26 of the clamper 20, there is provided a slanting annular part 26 a for alignment having a shape along the frusto-conical surface of the centering projection 12 a of the turntable 12. Inclined annular portion 26a at the inner periphery of annular portion 26
A suction disk portion 24 made of a ferromagnetic material is internally fixed to the upper side.

An annular plate-shaped vibration-damping rigid portion 28 is formed outside a lower portion of the clamping annular portion 26, and a flange-shaped portion 30 provided on the outer peripheral upper portion of the vibration-damping rigid portion 28 and the clamping annular portion 26. Between,
A fall prevention groove 32 is formed. The fall prevention groove 32
Inside, an annular support inner peripheral portion 34 (fixed to the device) is located in a non-contact state that does not hinder rotation of the clamper 20.

Therefore, the vibration generated in the vibration damping rigid portion 28 during rotation at the speed required for the CD-ROM drive (about 10,000 rpm) is the vibration damping rigid portion 28 and the clamping annular portion 26 supporting the same. Because of its high rigidity, the vibration of the CD-ROM 36 is extremely smaller than the vibration of the CD-ROM 36 when it is rotationally driven by a conventional ordinary driving device. The proximity planar portion 28a, which is the lower surface of the vibration damping rigid portion 28, is an annular plane perpendicular to the axis, and its axial position is the bottom surface of the clamping annular portion 26 perpendicular to the axis. Above about 0.3 mm (i.e., the gap d) from the clamping annular surface 26b. Further, the radius r of the vibration damping rigid portion 28 is the CD-ROM 36 which is a target flat body.
Is about two thirds of the radius of the vibration damping rigid portion 28,
CD-ROM made of lightweight and highly rigid material
A thickness slightly smaller than the thickness of 36 is sufficient.

The CD-ROM 36 has a central fitting hole 36.
a is fitted on the centering projection 12a and is aligned, and is placed on the receiving annular plate 12b of the turntable 12 at the non-recording portion around the center fitting hole 36a, and When the suction disk portion 24 is magnetically attracted to the clamp magnet 18 in a state where the portion 26a is fitted and aligned with the truncated conical surface of the alignment projection 12a, the clamping annular surface 26b of the clamper 20 CD-ROM 3 between the receiving annular plate portions 12b
The non-recording inner peripheral portion 6 is pinched and held in the axial direction. The suction disk part 24 is in contact with the upper surface of the centering projection 12a.

The clamping pressure of the clamper 20 on the CD-ROM 36 is released, and the turntable 12 releases the CD-ROM 3
To remove 6, the drive motor 10 provided with the turntable 12 is moved downward from the state of FIG. 1 to release the magnetic attraction between the suction disk portion 24 and the clamp magnet 18. At that time, the clamper 20 is lowered from the state shown in FIG. When the CD-ROM 36 is set on the turntable 12 and the drive motor 10 is raised, the suction disk portion 24 and the clamp magnet 18 are magnetically attracted, and the drive motor 10 and the clamper 20 are also raised. 1, the clamping annular surface 26b of the clamper 20 and the receiving annular plate 1
The non-recording inner peripheral portion of the CD-ROM 36 is clamped and held during 2b. In this case, the annular support inner peripheral portion 34 is
In a non-contact state that does not hinder the rotation of. For example, the driving motor 10 is fixed, the annular support inner peripheral portion 34 can be moved up and down, and the clamping and holding of the CD-ROM 36 and the release thereof can be performed only by the vertical movement of the clamper 20 due to the vertical movement of the annular support inner peripheral portion 34. It can also be done.

The CD-ROM 36 has its center fitting hole 36
a is fitted to the centering projection 12a and aligned, and in a state where the pressure is held between the receiving annular plate portion 12b of the turntable 12 and the clamper 20, the proximity planar shape of the vibration damping rigid portion 28 is formed. The portion 28a is about 0.3 m above the upper surface of the CD-ROM 36.
m. The clamping annular portion 26 is located on the inner peripheral portion of the vibration damping rigid portion 28, and the radius of the vibration damping rigid portion 28 is the CD-ROM 3.
It covers approximately two thirds of the radius of 6.

The turntable 12, the CD-ROM 36, and the clamper 20 can be integrally rotated by rotating the drive motor 10 at a predetermined speed in this state in the air inside the apparatus case or the like. This allows
The proximity flat portion 28a of the vibration damping rigid portion 28 is replaced with a CD-ROM.
36, the vibration-damping rigid part 28 is brought close to the upper surface of the CD-R.
The OM 36 is rotated at a speed equal to the rotation speed of the OM 36, and the air between them is substantially shaken by the vibration damping rigid part 28 and the CD-ROM 36.
It can be rotated at the same rotation speed as
There is no turbulence in the air above the ROM 36, and the airflow is stable. Therefore, without covering a portion required for data reading on the lower surface of the CD-ROM 36, the CD-ROM 3
6 can be effectively suppressed and the CD
-There is no possibility that the ROM 36 may be damaged or deformed.
Since the rigidity of the vibration damping rigid portion 28 is higher than that of the CD-ROM 36, the phenomenon that the vibration damping rigid portion 28 and the CD-ROM 36 strike (or resonate) and the vibration is expanded can be avoided. If at least one of the CD-ROM 36 and the vibration suppression rigid portion 28 vibrates, the CD-ROM
The pressure fluctuates around the vibrating portion in the space between 36 and the vibration damping rigid portion 28. Then, the air existing in the space generates a resistance in the opposite direction to the vibration of the vibrating part, and acts to suppress the vibration. The vibration generated in the CD-ROM 36 is suppressed by the so-called air damper effect. Can be.

FIGS. 2 to 4 are longitudinal sectional views of a CD-ROM drive device as another example of the embodiment of the method for damping a rotating flat plate and the device for damping a rotating flat plate according to the present invention. FIG. 2 to FIG. 4 that are the same as in FIG.
2 shows the same part as FIG. 1. A detailed description of them will be omitted.

The clamper main body 122 shown in FIGS.
Is composed of a clamping annular portion 126 and an annular outer peripheral member 127 made of a non-ferromagnetic metal plate formed by press molding. Annular outer member 1
Reference numeral 27 has a vibration damping rigid portion 128, a flange portion 130, and a falling-off prevention groove 132, and is externally fitted and fixed to the clamping annular portion 126. The proximity planar portion 12 which is the lower surface of the vibration damping rigid portion 128
8a is about 0.3 mm above the clamping annular surface 126b as in the example of FIG. The outer peripheral portion of the vibration suppression rigid portion 128 in the annular outer peripheral member 127 in FIG. 2 is flat, but in the case of FIG.
Is provided.

The clamper main body 222 shown in FIG. 4 includes a clamping annular portion 226 and a vibration damping rigid portion 228 made of fiber reinforced plastic which is externally fitted and fixed to the clamping annular portion 226. The lower surface of the vibration damping rigid portion 228 is a plane portion 228a for approach perpendicular to the axis, but the thickness of the vibration damping rigid portion 228 in the axial direction is radially inward from the outer peripheral portion for higher rigidity. The thickness is gradually increased toward. Proximity planar portion 228a
Is approximately 0.3 mm from the clamping annular surface 226b as in the example of FIG.
mm above.

FIG. 5 is a longitudinal sectional view of a CD-ROM drive device as still another example of the embodiment of the method for damping a rotating plate-like body and the device for damping a rotating plate-like body according to the present invention. FIG.
1 denote the same parts as in FIG. A detailed description of them will be omitted.

In this example, the clamper 2 shown in FIG.
0 of the vibration suppression rigid portion 28 is approximately 2
2 mm thick, a 2-mm-thick felt flexible portion 40 in the form of an annular plate is coaxially adhered and fixed to the lower surface of the vibration damping rigid portion 28. The CD-ROM 36 has a central fitting hole 3
6a is fitted and aligned with the centering projection 12a, is held between the receiving annular plate portion 12b of the turntable 12 and the clamper 20, and the contact surface which is the lower surface of the flexible portion 40 is a CD. −
It is in contact with the upper surface of the ROM 36 in a substantially non-pressed state.

The turntable 12, the CD-ROM 36, and the clamper 20 can be integrally rotated by rotating the drive motor 10 at a predetermined speed in this state in the air inside the apparatus case or the like. This allows
The contact surface of the flexible portion 40 bonded and fixed to the lower surface of the vibration damping rigid portion 28 is brought into contact with the upper surface of the CD-ROM 36, and the vibration damping rigid portion 28 and the flexible portion 40 are rotated at a speed equal to the rotational speed of the CD-ROM 36. Can be rotated. That is, due to the vibration damping rigid portion 28 and the flexible portion 40, there is substantially no air flow on the upper surface of the CD-ROM 36. Therefore, the vibration generated in the CD-ROM 36 can be effectively suppressed, and there is no possibility that the CD-ROM 36 is damaged or deformed. Also the vibration damping rigid part 28 and CD-ROM
It is possible to avoid the phenomenon that the vibrations are expanded by the striking of the vibrations 36.

It should be noted that the vertical positional relationship in the above description of the embodiment is merely for convenience of explanation based on the drawings, and does not limit the actual use state and the like. For example, the radii (r) of the vibration damping rigid portions 28 and 128 and the distances (corresponding to the gap d) from the clamping annular surfaces 26b, 126b and 226b to the planar portions 28a, 128a and 228a for proximity are also as described above and illustrated. But not
The radius r is desirably 50% or more and 1.1 times or less of the target flat body, and the gap d is desirably up to about twice the thickness of the target flat body. In addition, C is used as a rotating flat body.
Although a recording disk such as a D-ROM has been described as an example, the present invention can also be applied to a disk having another similar shape such as a circular saw.

[0064]

According to the method for damping a rotating flat plate according to the present invention, the vibration damping rigid portion is rotated at the same speed in opposition to one surface of the target flat plate, thereby forming the target flat plate in the fluid. Vibrations generated in the target plate-like body due to the action of the fluid flow generated by the body rotating around a constant axis in its thickness direction are effectively suppressed.

According to the method for damping a rotating flat body according to claim 2 and the vibration damping device for a rotating flat body according to claims 3 and 4, the planar portion for proximity of the vibration damping rigid portion is applied to the target flat body. In the state of being close to each other, it is possible to effectively suppress the vibration generated in the target flat body without causing damage or deformation of the target flat body, and the vibration damping rigid portion and the target flat body hit each other. The phenomenon that the vibration is enlarged can be avoided.

According to the method for damping a rotating flat plate according to the fifth aspect and the vibration damping device for a rotating flat plate according to the sixth and seventh aspects, the flexible portion supported by the vibration-damping rigid portion is applied to the target flat plate. In the abutted state, the vibration generated in the target flat body can be effectively suppressed without causing the target flat body to be damaged or deformed, and the vibration-damping rigid portion and the target flat body hit each other. Thus, the phenomenon that the vibration is enlarged can be avoided.

According to the rotating machine of the eighth aspect, there is no fear of causing damage or deformation of the target plate-shaped body to be rotated.
Vibration generated in the target flat body can be effectively suppressed.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a CD-ROM drive device and an enlarged view of a main part thereof.

FIG. 2 is a longitudinal sectional view of another CD-ROM drive device and an enlarged view of a main part thereof.

FIG. 3 is a longitudinal sectional view of still another CD-ROM drive device.

FIG. 4 is a longitudinal sectional view of still another CD-ROM drive device.

FIG. 5 is a longitudinal sectional view of still another CD-ROM drive device.

FIG. 6 is a longitudinal sectional view of a conventional CD-ROM drive device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Drive motor 10a Rotating shaft 12 Turntable 12a Aligning projection 12b Receiving annular plate 12c Rubber sheet 14 Annular groove 16 Back yoke 18 Magnet for clamping 20 Clamper 22 Clamper main body 24 Suction disk part 26 Clamping annular part 26a Inclined annular portion 26b Clamping annular surface 28 Vibration damping rigid portion 28a Planar portion for proximity 30 Flange portion 32 Fall-off prevention groove 34 Annular support inner peripheral portion 36 CD-ROM 36a Center fitting hole 40 Flexible portion 122 Clamper body 126 Circular annular portion 126b Clamping annular surface 127 Annular outer peripheral member 128 Vibration damping rigid portion 128a Planar portion for approach 128b Rising portion 130 Flange portion 132 Fall-off prevention groove 222 Clamp body 226 Clamping annular portion 226b Clamping annular surface 228 Vibration rigid part 228a Planar part for proximity

Claims (8)

[Claims] 1. A method for suppressing vibration mainly in a thickness direction generated in a target flat plate by rotating the flat plate in a fluid around a constant axis in a thickness direction thereof, the method comprising: A vibration-damping stiffness part that is higher in rigidity than a flat plate body and generated when rotating is smaller than the target flat plate body. Rotate at the same speed as the rotation speed of the flat plate, and in the annular or circular portion over a predetermined radial width between the opposing vibration suppression rigid portion and the target flat plate, A method of damping a rotating flat body, characterized by substantially eliminating the flow of fluid relative to both the body and reducing the vibration to a degree that can suppress the vibration. 2. The vibration-damping rigid portion has an annular or circular approaching flat portion extending over a predetermined radial width, and the approaching flat portion is close to one side surface of the target flat plate. The vibration suppression rigid portion is rotated at a speed equal to the rotation speed of the target plate-like body in a state in which the proximity flat portion and the target plate-like body are coaxial, and the proximity planar portion of the vibration suppression rigid portion is formed. In the annular or circular portion extending over a predetermined radial width between the target flat plate and the target flat plate, the relative fluid flow to both the proximity flat portion and the target flat plate of the vibration damping rigid portion rotating at the same speed. The method according to claim 1, wherein the flow is substantially eliminated or the vibration is reduced to an extent that the vibration can be suppressed. 3. An apparatus mainly for suppressing vibrations in a thickness direction generated in a target flat body by rotating the flat body in a fluid around a constant axis in a thickness direction of the target flat body. A vibration-suppressing rigid portion having an annular or circular approaching planar portion over the radial width of the vibration plate, and having higher rigidity than the target flat plate member, and vibration generated during rotation being smaller than that of the target flat plate member; The vibration-damping stiffness portion of the target plate-like body is placed in a state in which the planar portion for proximity is close to one side surface of the target plate-like body and the planar portion for proximity and the target plate-like body are coaxial. It has the same speed rotation mechanism that can rotate at the same speed as the rotation speed, and the target plate-like body in a state where the proximity flat part of the vibration damping rigid part is close to the target plate-shaped body over a predetermined radial width And the vibration suppression rigid part rotate at the same rotation speed. It allows mainly the vibration damping device of the rotating flat body, wherein the vibration in the thickness direction is suppressed to occur to the target flat body. 4. A pair of squeezing members capable of squeezing and holding squeezing a central portion of a target flat body in a thickness direction thereof, and one or both of the squeezing members of an axial center line in the squeezing direction. A rotating support mechanism that rotatably supports the object, and one of the pressing members is configured such that the central portion of the target plate is held in the thickness direction by the two pressing members in the thickness direction of the target plate. A vibration-damping rigid portion having a planar portion for proximity approaching one side of the body and being coaxial with the target plate-like body is provided, and the central portion of the target plate-like is pressed by its both pressing members in the thickness direction. 4. The rotating flat body according to claim 3, wherein one or both of the pressing members are supported by a rotation support mechanism and rotated in the held state, whereby the target flat body and the vibration damping rigid portion rotate at the same rotation speed. Vibration control device. 5. A flexible portion capable of blocking a flow of a predetermined fluid in a vibration-damping rigid portion, wherein one side is an annular or circular contact surface over a predetermined radial width. Side is supported so that the vibration damping rigid portion and the flexible portion can rotate substantially integrally around a predetermined axis in a direction perpendicular to the contact surface of the flexible portion, and the contact surface is formed in the target flat plate shape. The vibration-damping rigid part and the flexible part are substantially integrally rotated at a speed equal to the rotation speed of the target plate-shaped body while the abutment surface and the target plate-shaped body are coaxial with each other while being in contact with one side of the body. The relative fluid to both the vibration-damping rigid part and the target plate-shaped body in an annular or circular portion extending over a predetermined radial width in the flexible part between the opposed vibration-damping rigid part and the target flat-plate-shaped body To substantially eliminate the flow or reduce the vibration to the extent that it can be suppressed. Damping method of a rotating plate-shaped member according to claim 1, wherein. 6. An apparatus for suppressing mainly vibration in a thickness direction generated in a target flat body by rotating the flat body in a fluid around a constant axis in a thickness direction thereof in a fluid. A vibration-damping rigid portion that is higher in rigidity than the flat plate and generates less vibration when rotating than the target flat plate, and one side is an annular or circular contact surface that extends over a predetermined radial width. Is supported by the vibration damping rigid portion so that the side can rotate substantially integrally with the vibration damping rigid portion around a predetermined axis in a direction perpendicular to the contact surface, and is capable of blocking the flow of a predetermined fluid. Portion, the vibration-damping rigid portion and the flexible portion, the contact surface is in contact with one side of the target plate-shaped body and the contact surface and the target plate-shaped body are coaxial, the target plate-shaped The same speed rotation that can rotate at the same speed as the body's rotation speed The target flat body has a mechanism, and the target flat body and the flexible portion rotate at the same rotation speed in a state where the contact surface of the flexible portion is in contact with the target flat body over a predetermined radial width. A vibration control device for a rotating flat plate, characterized in that vibrations generated mainly in the thickness direction are suppressed. 7. A pair of squeezing members capable of holding and releasing squeezing of the central portion of the target flat plate in its thickness direction, and connecting one or both of the squeezing members to the axis of the squeezing direction. A rotating support mechanism that rotatably supports the object, and one of the pressing members is configured such that the central portion of the target plate is held in the thickness direction by the two pressing members in the thickness direction of the target plate. It has a vibration-damping rigid part that supports a flexible part that has an abutment surface that is coaxial with the target flat body while abutting on one side surface of the body. 7. The rotation according to claim 6, wherein one or both of the pressing members are rotated by being supported by a rotation supporting mechanism in a state where the pressing member is held in a state where the target plate-shaped member and the vibration damping rigid portion rotate at the same rotation speed. Vibration control device for flat body. 8. A rotary machine for rotating an object flat body in a fluid around a constant axis in a thickness direction thereof, wherein the vibration damping device according to claim 3, 4, 6, or 7 is provided. A rotating machine provided to suppress mainly vibrations in a thickness direction generated in a target flat body when the flat body is rotationally driven.