JP2000132905A - Rotary body driver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To assure safe and stable rotation of a rotary body with simplified structure by loading a rotary body, which is loaded to a shaft to integrally or mutually rotate, to the shaft side via a vibration absorbing member consisting of a flexible substance to reduce vibration of rotary body. SOLUTION: A hollow cylindrical collar 11 is fitted and fixed to a rotating shaft 3 and the center hole of the rotary body P is fixed to the external circumference side of the collar 11 via a ring type vibration absorbing member 12. The vibration absorbing member 12 is formed of a flexible substance to reduce vibration of the rotary body P. Vibration accelerating operation is alleviated when the number of rotations of shaft is increased in order to prevent large self-exciting phenomenon and reduce resonance frequency of the rotary body. Thereby, the rotating shaft easily reaches the rotating zone of low amplitude exceeding the resonance frequency. High viscosity coefficient C and low spring coefficient K of flexible substance are set in the range satisfying the relationship 1/C√mK<=M0 for the allowable limit amplitude M0 of the device when the mass of rotating body is defined as m.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotating body driving device that rotates a rotating body by a rotation driving force from a motor unit.

[0002]

2. Description of the Related Art In general, a rotary drive device in which various rotating members such as a flywheel and a recording medium disk are connected to an output portion of a motor unit to rotate at high speed is widely used in various kinds of devices. I have. In such a high-speed rotation drive device, when the center of gravity of the rotating body is at a position deviated from the center of rotation, a large vibration is generated even by a slight imbalance of the rotating body based on the center of gravity of the rotating body. Would. Since the unbalanced vibration is caused by centrifugal force, the amplitude increases as the rotational speed increases, and the rotational speed (1) corresponding to the resonance point is increased.
When the speed reaches the next critical speed, the vibration may be large enough to cause mechanical destruction.

Under such circumstances, various high-speed rotation driving devices employ a means for correcting the imbalance of the rotating body with high accuracy in minute units of about mg.cm. For example, in a grindstone spindle of a grinding machine, while monitoring the generated vibration using a vibration sensor, a fluid is driven into pockets arranged in a circumferential shape, thereby actively correcting imbalance. In addition, CD-
Since a rotating system including a removable media disk such as a ROM or a DVD has an eccentricity which is almost always required, a spindle motor of a rotary driving device handling such a high-speed rotating disk is particularly required in a high-speed rotation region. In order to cancel the eccentric center vibration, there is also one that adopts a relatively inexpensive vibration correcting device using a ball or the like, for example.

[0004]

However, in the case of the active vibration correcting device using the vibration sensor as described above, the device becomes very expensive, and it is difficult to adopt it in a wide variety of consumer devices. In practice, it is often impossible.
Further, the vibration correcting device in the latter rotary drive device for a removable medium such as a CD-ROM or DVD is configured at low cost, but tends to be unable to follow recent high-speed rotation.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a rotating body driving device which has a simple structure and can provide a good vibration absorbing function.

[0006]

In order to achieve the above object, according to the first aspect of the present invention, there is provided a shaft body, and a rotating body attached to the shaft body so as to rotate integrally or relatively to the shaft body. And a motor unit for driving the rotating body to rotate, wherein the rotating body is mounted on the shaft body side via a vibration absorbing member made of a flexible substance that reduces vibration of the rotating body. ing.

According to the second aspect of the present invention, the flexible material constituting the vibration absorbing member according to the first aspect includes a response amplitude Mn corresponding to a resonance frequency ωn of the rotating body and an allowable limit amplitude M0 of the apparatus. It has a high viscosity coefficient C and a low spring coefficient K, which are further reduced.

Further, according to the third aspect of the present invention, the high viscosity coefficient C and the low spring coefficient K of the flexible material according to the first aspect of the present invention, when the mass of the rotating body is m, the allowable limit amplitude of the device. For M0,

(Equation 2) Is set to satisfy.

Further, in the invention according to claim 4, the high viscosity coefficient C and the low spring coefficient K provided in the flexible material according to claim 3 reduce the relative phase angle θ between the vibration side and the response side. The value is set to a minimum value within a range that satisfies the condition described in claim 3 so that the value is inverted in the rotation region.

[0010] On the other hand, in the invention according to claim 5, the spring coefficient K of the flexible material according to claim 2 indicates the rotation speed Rn at the resonance point of the rotating body, The rotation speed is set in a range where the rotation speed is lower than the minimum rotation speed R0 (Rn <R0).

In the invention described in claim 6, the rotating body according to claim 1 is provided with vibration compensating means that balances rotation so as to offset the eccentricity of the rotating body.

Further, in the invention described in claim 7, the shaft body side described in claim 1 is provided with a surface falling prevention mechanism including a locking member disposed so as to be able to contact the rotating body in the axial direction. Have been.

According to the first aspect of the present invention, since the rotating body is held on the side of the shaft via the vibration absorbing member made of a flexible material, the rotation is started and the rotation speed of the shaft is gradually increased. Since the flexible material constituting the vibration-absorbing member relaxes the vibrating action at the time of causing the vibration, a large self-excitation phenomenon does not occur in the rotating body, and the vibration-absorbing material made of the flexible material is used. Since the resonance frequency is reduced by the member, a low-amplitude rotation region exceeding the resonance frequency is easily reached, and a safe and stable rotation drive is performed.

At this time, if the flexible material constituting the vibration absorbing member has the high viscosity coefficient C as in the second or third aspect of the present invention, the rotational speed may be at the resonance point. However, the vibration amplitude of the rotating body is suppressed to be lower than the allowable limit amplitude M0 of the device, and the destruction of the device is avoided.

If the spring coefficient K is low as in the second, third or fourth aspect of the present invention, the rotation speed of the rotating body exceeds the resonance frequency early, and the stable rotation is achieved. It is quickly shifted to the driving state.

Further, if the operating speed range of the rotator is set to a range higher than the speed at which resonance occurs, driving in a stable speed range becomes possible, and the drive is always performed. A good rotation state is obtained.

Further, if the vibration compensating means or the surface falling prevention mechanism is additionally provided as in the invention according to claim 6 or 7, a safer and more stable rotation drive is performed.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings. In the embodiment shown in FIG. 1, the present invention is applied to a rotating body driving device in which a high-speed rotating body P such as a polygon mirror used for a laser beam printer or the like is mounted on a motor unit M.

First, in the motor section M, the rotating shaft 3 is rotatable in a hollow cylindrical bearing sleeve 2 fixed to the base 1 by screws with a gap of several μm to several tens μm. The radial dynamic pressure bearing portions R, R are formed by the inserted dynamic pressure surface formed on the outer peripheral surface of the rotating shaft 3 and the dynamic pressure surface formed on the inner peripheral surface side of the bearing sleeve 2. I have. Further, a thrust dynamic pressure bearing portion S is constituted by a dynamic pressure surface formed on the illustrated lower end surface of the rotating shaft 3 and a dynamic pressure surface of a thrust plate 4 attached so as to cover the illustrated lower end opening of the bearing sleeve 2. Have been. The radial dynamic pressure bearing portions R, R and the thrust dynamic pressure bearing portion S are provided with a spiral-shaped dynamic pressure generating groove (not shown).

Further, a stator core 5 having radial salient pole portions is fixed to an outer peripheral portion of the bearing sleeve 2, and a driving coil 6 is wound around each radial salient pole portion of the stator core 5. I have.

On the other hand, a center hole 7a provided in a substantially cup-shaped rotor 7 is fitted and fixed to a portion of the rotary shaft 3 projecting upward from the bearing portion in the figure.
At the same time, the rotor 7 is configured to rotate integrally.
An annular flange portion 7b provided on an outer peripheral portion of the rotor 7
An annular permanent magnet 8 is fixed on the inner peripheral wall of the stator core 5 over the entire circumference. The inner peripheral wall of the annular permanent magnet 8 is radially opposed to the outer peripheral wall of the radial salient pole portion of the stator core 5 described above. The arrangement has been made.

Further, a rotating body P such as the above-mentioned polygon mirror is fixed to the upper end of the rotating shaft 3 in the figure. More specifically, a hollow cylindrical collar 11 is fitted and fixed to the rotating shaft 3 by mechanical joining means such as press-fitting, shrink-fitting, or bonding, and is attached to the outer peripheral surface side of the collar 11. The center hole of the rotating body P is fixed via a ring-shaped vibration absorbing member 12. The vibration absorbing member 12 is formed of a flexible material so as to reduce the vibration of the rotating body P. Examples of the flexible material include silicon rubber, other natural or synthetic rubber, and various resins having the following characteristics. Materials are adopted.

That is, the flexible material constituting the vibration absorbing member 12 is set to a high viscosity coefficient C and a low spring coefficient K satisfying the following conditions, and the resonance frequency ωn of the rotating body P , And a function of reducing the vibration amplitude corresponding to the resonance frequency ωn to a safe region. First, when the mass of the rotating body P is m, the resonance frequency ωn of the rotating body P is

(Equation 3) As shown in FIG. 2, a maximum response amplitude Mn is generated corresponding to the resonance frequency ωn.

That is, FIG. 2 shows the relationship between the rotational speed R (horizontal axis) and the amplitude M (vertical axis) of the rotator P, and the viscosity coefficient C and the viscosity coefficient of the flexible material constituting the vibration absorbing member 12. Although the spring coefficient K is expressed as a parameter, as shown by, for example, a curve a in the figure, the device of the apparatus corresponds to the resonance frequency ωn of the rotating body P generated at the rotation speed Rn at the resonance point. The maximum response amplitude Mn occurs. Note that the maximum response amplitude Mn at this time is expressed as a ratio to the applied amplitude.

On the other hand, the amplitude M on the response side with respect to the amplitude on the vibration side of the rotating body P is

(Equation 4) It is expressed as here,

(Equation 5) It is.

In the present invention, the response amplitude M of the rotating body P is set so as not to exceed the limit amplitude M0 allowed for the apparatus. That is, when the above equation is introduced for the condition of M ≦ M0,

(Equation 6) However, to satisfy this, the flexible material constituting the vibration absorbing member 12 is selected to have a high viscosity coefficient C and a low spring coefficient K. As a result, for example, the characteristic curve is set as shown by the curve b in FIG.
Is smaller than the allowable limit amplitude M0. The allowable limit amplitude M0 at this time is also a ratio with respect to the added amplitude.

Further, the above-described resonance frequency ω of the rotating body P
n, the resonance frequency ωn of the rotating body P
Varies in proportion to the spring coefficient K of the flexible material constituting the vibration absorbing member 12, but the spring coefficient K of the flexible material of the vibration absorbing member 12 in the present embodiment is different from the resonance frequency ω
n is set as small as possible so as to reduce n. For example, when the range of the number of rotations of the rotating body P is set to a range indicated by R0 to R1 in FIG. 2, the spring coefficient K of the flexible material of the vibration absorbing member 12 in the present embodiment corresponds to a resonance point. The rotation speed Rn is set so as to be lower than the minimum use rotation speed R0 in the use rotation region.

FIG. 3 shows the viscosity coefficient C and the spring coefficient K.
Is the relative phase angle θ between the excitation side and the response side
(Vertical axis) is expressed in relation to the rotational speed R of the rotating body P (horizontal axis). As shown in FIG.
Varies according to the viscosity coefficient C and the spring coefficient K of the flexible material constituting the vibration absorbing member 12 described above. In the present embodiment, by setting the viscosity coefficient C and the spring coefficient K as small as possible within the range of the aforementioned conditions, for example, as shown by the curve a or b in FIG. The phase angle θ is set to be reversed as rapidly as possible near the resonance point.

In this embodiment, since the rotating body P is held on the rotating shaft 3 via the vibration absorbing member 12 made of a flexible material, the rotating body P starts rotating and the rotating speed of the rotating shaft 3 is gradually increased. The vibration effect when raised to the
The vibration is mitigated by the vibration reducing action of the flexible material that constitutes 2, and as shown by the curve b in FIG. 2, for example, a safe and stable rotational drive is performed without generating a large self-excitation phenomenon. . In addition, since the resonance point is shifted to the low rotation region by the vibration absorbing member 12 made of the flexible material, it is easy to reach the low amplitude rotation region exceeding the resonance frequency, and the safe and stable rotation is achieved. Drive is performed.

Specifically, in the present embodiment, the vibration absorbing member 1
2 has a high viscosity coefficient C, so that the vibration amplitude M of the rotating body P is always larger than the allowable limit amplitude M0 of the device even when the rotation speed reaches the resonance point. Since it is kept low, the destruction of the device is reliably avoided.

In this embodiment, since the spring coefficient K of the flexible material constituting the vibration absorbing member 12 is set to be low, the rotation speed of the rotating body P exceeds the resonance frequency at an early stage. The state is quickly shifted to the rotated driving state. In particular, in the present embodiment, the vibration absorbing member 1
By setting the viscosity coefficient C of the flexible substance constituting 2 as small as possible, the relative phase angle θ is set to be sharply reversed as shown by the curve a or b in FIG. In this case, a stable rotational driving state is shifted even earlier.

Similarly, by setting the spring coefficient K of the flexible substance constituting the vibration absorbing member 12 to be low, the rotational speed range R0 to R1 of the rotating body P in this embodiment is used.
However, since it is always set higher than the rotational speed Rn at which resonance occurs, it is possible to always drive in a stable rotational region,
A better rotation state can be obtained.

Next, in the embodiment shown in FIGS. 4 and 5 in which the same components as those of the rotary drive device shown in FIG. Known vibration compensation means 20 and 30 for balancing the rotation of P are additionally provided.

First, the vibration compensating means 20 in the embodiment according to FIG. 4 has a hollow annular case 21 on the lower surface side of the outer peripheral portion of the rotating body P, , A plurality of balance balls 22
Are inserted in a freely movable state, and the balance balls 22 are arranged at positions where the eccentricity of the rotating body P is offset during rotation, thereby achieving rotational balance.

The vibration compensating means 30 in the embodiment shown in FIG. 5 includes a hollow annular case 31 on the lower surface of the outer peripheral portion of the rotating body P, , A predetermined viscous fluid 32 is injected, and at the time of rotation, the viscous fluid 32 is distributed so as to cancel out the eccentricity of the rotating body P, thereby achieving a rotational balance.

In the embodiment shown in FIGS. 4 and 5, in addition to the vibration damping action of the above-described embodiment, the vibration itself is canceled, and a more secure and stable rotational drive is performed. Will be

On the other hand, in the embodiment shown in FIGS. 6 and 7 in which the same components as those of the rotary drive device shown in FIG. The present invention is applied to a media rotation drive device using a removable media disk (hereinafter, simply referred to as a disk) M such as a DVD.

First, in the embodiment shown in FIG.
A disk holding member 41 is fitted and fixed to the rotating shaft 3, and a central boss 41 a of the disk holding member 41 is provided.
A disc-shaped flange plate 41b is integrally provided so as to extend in the radial direction from the lower end in the figure. The outer peripheral surface of the center boss 41a and the flange plate 41
A vibration-absorbing member 42 made of a flexible substance is attached on the upper surface of the drawing b in a layered manner, and a turntable 43 is fixed via the vibration-absorbing member 42. The vibration absorbing member 42
Is formed of a flexible material that reduces the vibration of the rotating body P, as in the above-described embodiments. As the flexible material, silicon rubber or other natural or synthetic rubber, various resin materials, or the like is used. Have been.

At the center of the turntable 43,
A mounting base 43a fitted into the center hole of the disk D is formed so as to protrude by a predetermined amount in the axial direction.
The center hole of the disk D is mounted along a tapered surface formed on the outer peripheral surface of the disk D, and the disk D is locked at a position corresponding to the inner diameter of the center hole.
Is adapted to be fitted to the turntable 43 in a radially immovable state.

A locking member 41c which constitutes a mechanism for preventing the disk D from falling down is provided on the outer peripheral edge of the flange plate 41b of the disk holding member 41. The locking member 41c is formed of a small projection piece protruding in the axial direction from the outer peripheral edge portion of the flange plate 41b, and is disposed so as to face the lower surface of the turntable 43 in the axial direction in the drawing. That is, when the turntable 43 rotates in a plane inclined from a horizontal plane due to the vibration when the turntable 43 and the disk D are rotationally driven together with the rotation shaft 3, the inclination angle of the turntable 43 becomes a fixed amount. When it becomes larger, the bottom side of the turntable 43 comes into contact with the tip of the locking member 41c, so that the inclination angle of the disk D does not exceed the allowable range. I have.

Further, in the embodiment shown in FIG. 7, the member 51 corresponding to the disk holding member 41 of the embodiment shown in FIG. 6 has a large-diameter flange plate 51a. A vibration absorbing member 52 made of the same flexible substance as in each of the above-described embodiments is provided on the flange plate 51a.
Are applied in layers, and via the vibration absorbing member 52,
A turntable 53 is placed.

At the center of the turntable 53,
A mounting table 53a that fits into the center hole of the disk D is formed so as to protrude by a predetermined amount in the axial direction.
The center hole of the disk D is mounted along the tapered surface formed on the outer peripheral surface of the disk D, and the disk D is locked at a position corresponding to the center hole, whereby the disk D is attached to the turntable 53. On the other hand, it is configured to be fitted in a radially immovable state.

An engaging member 51c constituting a mechanism for preventing the disk D from falling down is provided on the outer peripheral edge of the flange plate 51a of the disk holding member 51.
The locking member 51c is composed of a small projection piece that protrudes in the axial direction from the outer peripheral edge of the flange plate 51a, and is disposed so as to face the bottom surface of the turntable 53 in the axial direction. That is, when the turntable 53 rotates in a plane inclined from a horizontal plane due to vibration when the turntable 53 and the disc D are driven to rotate together with the rotating shaft 3, the inclination angle of the turntable 53 becomes larger than a certain amount. Then, the bottom surface of the turntable 53 comes into contact with the distal end portion of the locking member 51c, so that the inclination of the disk D does not exceed the allowable range.

Further, a disc holder 54 is disposed above the disc D in the figure. The disc holder 54 is formed of a disc-shaped member having a diameter slightly smaller than that of the turntable 53, and is mounted so as to abut on the center portion of the disc D to fix the disc D.
A suction portion 55 made of a predetermined magnetic material is embedded in the center of the disc press 54 so as to be exposed on the lower surface side of the disc press 54 in the drawing. The disk holder 54 and the turntable 53 are firmly fixed by being attracted in the axial direction by the permanent magnet 56 as a magnetic attraction means.

In the embodiment shown in FIGS. 6 and 7, in addition to the vibration damping action of the above-described embodiment, safer and more stable rotational driving is performed.

Next, in the embodiment shown in FIG.
The ball member 51d is used as the locking member in the embodiment according to FIG. 7 described above, whereby the movement of the turntable 53 in the radial direction is performed more smoothly.

The embodiment shown in FIGS. 9 and 10 is different from the embodiment shown in FIGS. 4 and 5 in that the eccentricity compensation mechanisms 20 and 30 are different from the embodiment shown in FIGS. , 41c in combination. Further, the embodiment shown in FIG. 11 is different from the eccentricity compensation mechanism 60 having a weight portion of a predetermined mass.
The face-fall prevention mechanisms 41, 41 in the embodiment of FIG.
These are used in combination.

Although the embodiments of the present invention made by the inventor have been specifically described above, the present invention is not limited to the above-described embodiments, and can be variously modified without departing from the gist thereof. Needless to say. For example, the rotating body to which the present invention can be applied is not limited to the polygon mirror and the media disk as in the above-described embodiment, but may be a case where various other rotating bodies such as a flywheel are used. However, the present invention can be similarly applied.

Further, the present invention is not limited to the shaft rotary type device as in each of the above-described embodiments, but can be similarly applied to a fixed shaft type device.

[0050]

As described above, according to the first aspect of the present invention, the rotation is started by holding the rotating body on the shaft body side through the vibration absorbing member made of a flexible material, thereby reducing the rotation speed of the shaft body. In addition to preventing the self-excited phenomenon in the rotating body by relaxing the vibration effect when gradually increasing, the resonance frequency is reduced so that it can easily reach the low-amplitude rotation region beyond the resonance frequency. Therefore, the rotating body can be driven safely and stably with a simple configuration, and the reliability of the rotating drive device can be improved.

Further, according to the second or third aspect of the present invention, even if the rotational speed reaches the resonance point, the vibration amplitude of the rotating body is controlled to be lower than the allowable limit amplitude M0 of the device. By making the viscous material highly viscous, it is designed to avoid destruction of the device,
The effects described above can be further enhanced.

Further, according to the second, third or fourth aspect of the present invention, the viscosity coefficient C and the low spring coefficient K are set to be small so that the relative phase angle θ between the vibration side and the response side is rapidly reversed in a low rotation region. By doing so, since the rotation speed of the rotating body is configured to exceed the resonance frequency early, it is possible to quickly shift to a stable rotation driving state, and the above-described effect can be further enhanced. .

Further, in the fifth aspect of the present invention, the spring coefficient K of the flexible material is set so that the operating speed range of the rotating body is always higher than the speed at which resonance occurs. A good rotation state can be obtained in a stable rotation region, and the above-described effects can be further enhanced.

The invention according to claim 6 or 7 is provided with a vibration compensating means for canceling the vibration or a mechanism for preventing the surface from falling in addition to the above-mentioned invention, so that a more secure and stable rotational drive can be achieved. It is possible to further enhance the effects described above.

[Brief description of the drawings]

FIG. 1 is a cross-sectional explanatory view illustrating a structure of a rotating body driving device according to an embodiment of the present invention.

FIG. 2 Rotational speed (horizontal axis) and amplitude of vibration (vertical axis) of a rotating body
FIG. 4 is a diagram showing the relationship between the vibration coefficient and the viscosity coefficient of the vibration absorbing member as parameters.

FIG. 3 is a diagram showing a relationship between a rotation speed (horizontal axis) of a rotating body and a phase angle of vibration (vertical axis) using a viscosity coefficient and a spring coefficient of a vibration absorbing member as parameters.

FIG. 4 is an explanatory cross-sectional view illustrating a structure of a rotating body driving device according to another embodiment of the present invention.

FIG. 5 is a cross-sectional explanatory view showing a structure of a rotating body driving device according to still another embodiment of the present invention.

FIG. 6 is a cross-sectional explanatory view showing a structure of a rotating body driving device according to still another embodiment of the present invention.

FIG. 7 is a cross-sectional explanatory view showing a structure of a rotating body driving device according to still another embodiment of the present invention.

FIG. 8 is a cross-sectional explanatory view showing a structure of a rotating body driving device according to still another embodiment of the present invention.

FIG. 9 is an explanatory cross-sectional view illustrating a structure of a rotating body driving device according to still another embodiment of the present invention.

FIG. 10 is an explanatory cross-sectional view showing a structure of a rotating body driving device according to still another embodiment of the present invention.

FIG. 11 is a cross-sectional explanatory view illustrating a structure of a rotating body driving device according to still another embodiment of the present invention.

[Explanation of symbols]

 P Rotating body 3 Rotating shaft 12 Vibration absorbing member 20, 30, 60 Vibration compensating means D Media disk 41, 51 Disk holding member 41c, 51c, 51d Locking member (surface falling prevention mechanism) 42, 52 Vibration absorbing member

Continuation of the front page F term (reference) 5D109 DA12 5H607 AA04 AA12 BB01 BB14 BB17 BB25 CC01 CC05 DD03 EE10 EE38 FF12 GG02 GG05 JJ08 5H621 HH01 JK17 JK19

Claims (7)

[Claims] 1. A rotating body driving device comprising: a shaft body; a rotating body mounted so as to rotate integrally or relatively to the shaft body; and a motor unit for driving the rotating body to rotate. The rotating body driving device, wherein the rotating body is mounted on the shaft side via a vibration absorbing member made of a flexible material that reduces vibration of the rotating body. 2. The flexible material constituting the vibration absorbing member,
Response amplitude Mn corresponding to resonance frequency ωn of the rotating body
2. The rotating body driving device according to claim 1, further comprising: a high viscosity coefficient C and a low spring coefficient K that reduce the vibration amplitude from the allowable limit amplitude M0 of the apparatus. 3. The high viscosity coefficient C and the low spring coefficient K of the flexible material are given by: 3. The rotating body driving device according to claim 2, wherein the range is set to satisfy the following. 4. The high viscosity coefficient C and the low spring coefficient K of the flexible material so that the relative phase angle θ between the vibration side and the response side is reversed in a low rotation region. 4. The rotating body driving device according to claim 3, wherein the minimum value is set within a range satisfying the condition. 5. The spring coefficient K of the flexible material reduces the rotation speed Rn at the resonance point of the rotating body from the lowest rotation speed R0 of the operating speed range of the rotating body (Rn <Rn).
(R0) range is set.
The rotating body driving device as described in the above. 6. The rotating body driving device according to claim 1, wherein the rotating body is provided with vibration compensating means for balancing the rotation so as to cancel the eccentricity of the rotating body. 7. The apparatus according to claim 1, wherein a surface falling prevention mechanism including a locking member disposed so as to be axially abuttable against the rotating body is provided on the shaft body side. Rotating body drive.