JP2002078280A - Spindle motor and disk drive having the same - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a spindle motor in which a thrust bearing does not generate a separate collision motion even in a vibration environment without excessively increasing a pressing force constantly while maintaining a constant height of a thrust receiver. obtain. As a result, a disk drive device free from read / write errors, noise, and reduced bearing life caused by vibration and collision is obtained. SOLUTION: The shaft includes a shaft 31, a sleeve 32 surrounding the outer periphery thereof, and a thrust receiver 33 provided at one end of the sleeve and supporting one end of the shaft. The thrust receiver 33 is elastically pressed and held on the contact surface 32b of the sleeve.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spindle motor and a disk drive equipped with the spindle motor, and more particularly to a thrust bearing having a structure in which a thrust load is received at a tip of a shaft.

[0002]

2. Description of the Related Art HD / HD
2. Description of the Related Art Disk drives using an optical disk or the like as a medium are increasing in capacity. As the recording density increases accordingly, the read / write head requires extremely precise tracking. On the other hand, computers are often used in a portable manner, and everything including the housing has to be thinned and lightened. In this case, resonance is likely to occur with respect to external vibrations of the disk drive device, and read / write reliability is impaired. Under such circumstances, countermeasures against external vibrations have become an important issue for disk drive devices.

In a disk drive, a spindle motor for mounting and driving a disk also determines read / write reliability of the disk drive. And the point is mainly in bearings. In recent years, hydrodynamic bearings have been used as bearings with small NRRO (non-repetitive runout).
As a thrust bearing combined with this, there is a thrust bearing configured with a shaft tip and a thrust receiver opposed thereto. FIG. 9 shows an example of such a hydrodynamic bearing mechanism. As shown in the figure, a rotating shaft 101 is supported by being surrounded by a sleeve 102, and one end of the shaft is supported by a thrust receiver 103.

This bearing is often used because of its simple structure and small bearing loss. However, since the shaft and the thrust receiver are supported on only one opposing surface, they have a characteristic that they are separated when a force is applied in the opposite direction. The separated collision motion is remarkable when the natural frequency of the rotor matches the natural frequency of the housing.

[0005] Therefore, in general, both are constantly pressed by utilizing a magnetic attraction force or the like. And in order to be stronger against external vibration, it is necessary to always press with a large force that can counter the separation force due to vibration.
However, if the pressing force is set too high, not only the surface pressure generated at the contact portion of the thrust bearing becomes excessive, but also the radial component force generated due to slight unevenness increases. For this reason, there have been problems such as an increase in both radial and thrust bearing loss and a reduction in the bearing life.

[0006] In order to prevent the separated collision movement between the shaft and the thrust receiver, there is a method of floating the thrust receiver with respect to the sleeve with a cushion material. FIG. 10 shows an example described in JP-A-2-273047. This is to suppress the vibration caused by the collision of the shaft 113 with the elastic washer 112 interposed between the thrust receiver 111 and the holding portion behind the thrust receiver 111. In this case, the sleeve 114 has a bottomed structure, in which a metal 115 is provided, and a ball 116 is used at the tip of the shaft. However, in this structure, the height of the thrust receiver 111 easily changes with time, so that it is not suitable for a precise disk drive. As described above, the disk drive of recent years has an increased recording capacity, and the gap between the read / write head and the disk is precisely set.
Therefore, the fluctuation of the rotor height must be kept very small.

As another means for avoiding the separated collision movement due to resonance, there is a method of changing the rigidity of the housing of the disk drive device and other parts. Although this method is effective, the degree of freedom of the change is small in a situation where priority must be given to an increase in capacity and a reduction in thickness and weight.

[0008]

SUMMARY OF THE INVENTION Therefore, the present invention is capable of controlling the natural frequency of the rotor while maintaining the height of the thrust receiver constant without excessively increasing the steady pressing force. A spindle motor capable of reducing the separated collision motion of the bearing portion is obtained. Accordingly, it is an object of the present invention to provide a disk drive device having high read / write reliability while having a large capacity, thin wall, and light weight, and having a long life and low noise.

[0009]

In order to achieve the above object, the present invention provides a shaft, a sleeve surrounding the outer periphery thereof,
A spindle motor having a thrust receiver for supporting one end of a shaft, and a positioning member on the shaft side of the thrust receiver for positioning one end of the shaft axially with respect to the sleeve, the thrust receiver being elastically pressed and held by the positioning member; It is what it was. Further, a disk drive device is constituted by using it.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention comprises: a) a shaft, a sleeve surrounding the outer periphery thereof, a thrust receiver for supporting one end of the shaft, and a thrust receiver on the shaft side of the thrust receiver. A positioning member having one end positioned axially with respect to the sleeve; and b) a spindle motor in which a thrust receiver is elastically pressed and held by the positioning member.

Thus, the thrust receiver is elastically pressed and held on the positioning member. Then, first, when external vibration is applied and the pressing force of the shaft against the thrust receiver increases, the thrust receiver moves elastically. And by reducing the reaction force by moving, at the same time,
The amplitude can be attenuated by the hysteresis loss accompanying the movement. Therefore, it is possible to prevent a separate collision movement between the shaft and the thrust receiver in a vibration environment, and it is possible to prevent generation of noise and a reduction in the life of the thrust bearing. Second, the boundary condition of the connecting portion between the thrust receiver and the positioning member is changed from the conventional fixed support to the free support.
Therefore, when external vibration is applied to such an extent that the thrust receiver does not elastically move, the support rigidity of the thrust receiver can be reduced while maintaining the position in the thrust direction, thereby lowering the resonance point of the rotor. Can be. By the above two actions, it is possible to prevent the separated collision motion without setting the steady pressing force between the shaft and the thrust receiver to an excessive value, and to extend the life of the thrust radial bearing by setting the steady pressing force low. be able to.

In addition, there is provided a positioning member on the shaft side for positioning one end thereof in the axial direction. Thereby, the axial position of the thrust receiver can be kept constant under a normal environment without vibration. At the same time, the axial position of the thrust receiver can be kept constant for a long time without causing a change with time. Therefore, the disk height can always be maintained with high accuracy, and a read error due to a disk height defect does not occur in a drive device such as an HDD or an optical disk.

According to a second aspect of the present invention, there is provided a) a shaft, a sleeve surrounding the outer periphery thereof, and a thrust receiver disposed at one end of the sleeve and supporting one end of the shaft,
b) The spindle motor has a contact surface for axially positioning one end surface of the thrust receiver on the shaft side, and c) is a spindle motor in which the thrust receiver is elastically pressed and held on the contact surface of the sleeve.

As described above, the sleeve has the abutment surface for axially positioning one end surface of the thrust receiver on the shaft side.
That is, the thrust receiving / positioning member can be formed only by providing a step portion having a diameter larger than the shaft diameter in the sleeve, which is a member constituting the radial bearing. Therefore, machining can be performed simultaneously with the radial bearing portion, which is advantageous in terms of accuracy, space, cost, and the like, and a compact and high-performance spindle motor can be configured.

According to a third aspect of the present invention, a thrust receiver is provided.
Assuming that the mass of the rotating body is M [kg], 3 × 9.8 M to 1
The spindle motor according to claim 1, wherein the spindle motor is elastically pressed and held by a force of 0 × 9.8 M [N]. That is, the pressing force is set to a numerical value within a certain range. When the pressing force is equal to or more than the lower limit, the rotor height does not change under the environment of normal operation, and is displaced only when there is a large external vibration to exert the vibration damping effect. Therefore, the rotor height can be kept constant, the disk height is always kept with high accuracy, and a read error or the like due to a defective disk height does not occur. Further, when the pressing force is equal to or less than the upper limit value, it is possible to reliably perform elastic displacement with respect to external vibration and exhibit a vibration damping effect, thereby preventing a situation in which the device does not operate in a large vibration environment. In this manner, the vibration damping effect can be reliably exerted when necessary, and the rotor height can be kept constant at normal times.

According to a fourth aspect of the present invention, there is provided the spindle motor according to any one of the first and second aspects, wherein the member for elastically pressing the thrust receiver is a metal leaf spring. The metal leaf spring can constitute a pressing member having a high spring accuracy in a small space, has little change over time, and generates little dust. Therefore, a spindle motor having a compact and stable vibration damping action can be configured.

According to a fifth aspect of the present invention, the member for elastically pressing the thrust receiver is a rubber-like elastic material.
Or a spindle motor according to any one of (2) and (3).
The rubber-like elastic material has a high vibration damping property, and even if the thrust receiver does not move in the axial direction, the rubber-like elastic substance is in close contact with the thrust receiver and dampens the vibration propagating therein. Also, no concentrated load is applied to the thrust receiver. This structure is particularly suitable for a spindle motor used in a severe environment where external vibration is large.

According to a sixth aspect of the present invention, the distance in which the thrust receiver elastically moves in the axial direction is 0.1 mm or less.
A spindle motor according to claim 1. Thus, when a large vibration or impact is applied, the rotor height does not change more than the set limit, and the disk and the recording / reproducing head opposed thereto can be protected from destruction. In addition, it has a movement range sufficient to absorb and attenuate assumed external vibrations.

The invention according to claim 7 is the invention according to claims 1 to 6
A disk drive device equipped with the spindle motor according to any one of the above. In a vibrating environment, the separation collision movement of the thrust bearing part is attenuated, and the resonance phenomenon can be avoided. Therefore, it is possible to obtain a disk drive device that does not have read / write errors, noise, and reduced life of the thrust bearing due to the collision. it can. In a normal environment where external vibrations are small, the height of the rotor can be maintained with high accuracy. Therefore, the height of the disk can always be maintained with high accuracy, and a drive device suitable for HDDs, optical disks, and the like can be obtained.

[0020]

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

(Embodiment 1) FIG. 1 is a side sectional view showing a structure of a disk drive device according to an embodiment of the present invention, FIG. 2 is a partially enlarged sectional view of a spindle motor thereof, and FIG. 4A and 4B are sectional views, and FIG. 4A is a plan view of a leaf spring disposed behind the thrust receiver, and FIG. FIG. 5 shows resonance frequency data, and (a)
(B) is for the device of the conventional example, and (c) and (d) are for the device of the present embodiment.

The disk drive shown in FIG. 1 is an HDD.
A spindle motor 20 integrally formed with the housing is formed near the center of the housing 11. The spindle motor has a structure called an in-hub type, and the motor is built in the hub 21. The hub 21 has two disks 12 mounted thereon. The two disks are separated by a ring-shaped disk spacer 13, and the whole is fixed to a hub using a disk clamp 14. One male screw 15 is used for fixing, and is screwed with a female screw (not shown) provided at the center of the hub. The housing 11 has a side wall 11a surrounding and housing the disk 12, and a cover 16 is placed on the upper surface of the housing. The disk 12 is kept in a clean environment.

Although not shown, read / write heads are arranged close to both sides of each disk 12. Then, the servo actuator precisely tracks the surface of the disk, and performs read / write. Thus, a large amount of information is stored on the disk.

FIG. 2 is a partially enlarged sectional view showing the structure of the spindle motor 20. A cylindrical stator holding portion 11b projects from the bottom surface of the housing 11 toward the inside of the housing, and a stator assembly 22 is provided on an outer surface of the stator holding portion 11b.
Is attached. The bearing assembly 30 is fixed to the inner surface of the stator holding portion 11b. On the other hand, the rotor
It has a cup-shaped hub 21 on which a disk is mounted, and a magnet 23 fixed to the inner surface of the hub. The hub 21 is fixed to a rotatable shaft 31.
The magnet 23 faces the outer peripheral surface of the stator assembly 22 described above, and is provided with a rotational force by exciting the stator assembly 22. Then, the hub 21 and the disk 12 are rotationally driven.

As can be seen from the drawing, the bearing mechanism 30 employs a hydrodynamic bearing mechanism comprising a fixed sleeve 32 and a rotating shaft 31 as a radial bearing. On the other hand, the thrust bearing adopts a pivot structure composed of a shaft and a thrust receiver 33 facing the shaft. This thrust bearing has a small load loss and a small height variation in the thrust direction. However, since the load supporting ability is exerted only in one direction, it is necessary to always press the shaft 31 and the thrust receiver 33 so as not to be separated from each other by an external force. Therefore, in this motor, the magnet 23 and the stator assembly 22 are shifted from each other in the thrust direction to generate a magnetic attractive force. Further, a ring-shaped magnetic plate 24 is placed on the housing 11 at a position close to and opposed to the end face of the magnet 23, and also generates a magnetic attractive force.

Further, details of the bearing mechanism 30 will be described. FIG. 3 shows a partially enlarged sectional view of the bearing mechanism. In the figure, the radial bearing mechanism is, as described above, the inner peripheral surface 32 of the sleeve.
a and the outer peripheral surface 31b of the shaft, and a herringbone groove is formed on either of them. The thrust bearing is composed of a spherical surface 31a at the tip of the shaft and a thrust receiver 33 opposed thereto, and a disc spring 34 is disposed behind the thrust receiver 33.
Is supporting. It has a three-stage structure. Disc spring 3
Numeral 4 denotes a circular plate formed in a conical shape as shown in FIG. 4 and provided with radial slits.

The sleeve 32 has a contact surface 32b for axially positioning one end surface 33a of the thrust receiver 33 on the shaft side. The thrust bearing 33 is formed to have an outer diameter larger than the outer diameter of the shaft and large enough to fit the contact surface 32b. The thrust receiver 33 is elastically pressed and held on the contact surface 32b of the sleeve by a disc spring 34 disposed at the back. Therefore, it can be displaced in the axial direction.

Here, the thrust receiver 33 is formed of an inelastic member and is substantially rigid. Specifically, the surface is polished smoothly using a hard member such as a ceramic material or a cemented carbide. It has good wear resistance,
At the same time, the height in the thrust direction of the rotor is kept constant with high precision against the thrust load constantly applied.

The disc spring 34 (elastic pressing means) is provided to press the surface 33b of the thrust receiver on the side opposite to the shaft with a constant force.
Is fixed to the sleeve 32 in the thrust direction by a bottom plate 35 (holding member). The bottom plate may be integrated with the sleeve or with the housing.

The sleeve 32 surrounding these positions the thrust bearing 33 in the axial direction on its contact surface 32b (positioning member), and at the same time positions the thrust receiver on the contact surface perpendicular to the shaft. Further, on the outer periphery of the contact surface, there is a wall 32c for restricting the radial movement of the thrust receiver. Further, the sleeve 32 holds a bottom plate 35 that supports the disc spring. For this purpose, the bottom plate 35 is fixed by caulking the end 32d of the sleeve. In addition,
In this embodiment, the contact surface provided on the sleeve is used as the positioning member, but may be provided separately from the sleeve. Further, the contact surface may be a very small part on the outer peripheral side of the thrust receiver.

As described above, in the present embodiment, the thrust receiver 33 is elastically pressed and held on the contact surface 32b (positioning member) provided on the sleeve. Therefore, in a vibration environment, first, when external vibration is applied and the pressing force of the shaft 31 against the thrust receiver 33 increases, the thrust receiver elastically escapes and moves. Then, the reaction force is reduced by moving, and at the same time, the amplitude is attenuated by the hysteresis loss accompanying the movement. This movement phenomenon also extends the time interval of the separated collision movement. This means that the resonance frequency of the rotor decreases.

Second, the thrust receiver 33 and the contact surface 32b
The boundary condition of the coupling portion with the (positioning member) is changed from conventional fixed support to free support. Therefore thrust receiver 33
When external vibrations that do not move elastically are applied,
While maintaining the position in the thrust direction, the support rigidity of the thrust receiver 33 can be reduced, thereby lowering the resonance point of the rotor.

By such an action, it is possible to prevent a separate collision movement between the shaft 31 and the thrust receiver 33 in a vibration environment, and to lower the resonance frequency of the rotor. Prevents generation of noise and shortening of the life of the thrust bearing. Further, it is possible to prevent the separated collision motion without setting the steady pressing force between the shaft 31 and the thrust receiver 33 to an excessive value. Therefore, the life of the thrust bearing can be prolonged because the steady pressing force can be set low and there is no separated collision motion.

Further, there is provided a positioning member on the shaft side for positioning one end thereof in the axial direction. Therefore, in a normal environment without vibration, the axial position of the thrust receiver 33 can be kept constant and the rotor height can be kept constant for a long time without a change over time. As a result, the disk height is always maintained with high accuracy, and a read error or the like due to a disk height defect in a drive device such as an HDD or an optical disk does not occur.

In this embodiment, the sleeve 32
A contact surface 32b for axially positioning one end surface of the thrust receiver on the shaft side is provided. The thrust receiving and positioning member is formed only by providing a step portion larger than the shaft diameter on the sleeve. It can be machined simultaneously with the radial bearing, which is advantageous in terms of accuracy, space and cost. Therefore, a compact and high-performance spindle motor and disk drive can be configured.

In this embodiment, the member for elastically pressing the thrust receiver is formed of a metal leaf spring (disc spring 34). The metal leaf spring can constitute a pressing member having high spring accuracy in a small space, does not change with time, and generates less dust. Therefore, a spindle motor and a disk drive having a compact and stable braking action can be constructed.

Further, in this embodiment, by selecting the stroke of the disc spring 34, the distance in which the thrust receiver elastically moves in the axial direction is set to 0.1 mm or less. Thus, when a large vibration or impact is applied, the rotor height does not change beyond the set limit, and the disk and the recording / reproducing head opposed thereto can be protected from destruction. In addition, it has a movement range sufficient to absorb and attenuate assumed external vibrations.

In this embodiment, the thrust receiver 33 is used.
Is 3 × 9.8 M, where M is the mass of the rotating body.
It is elastically pressed and held with a force of 〜１０10 × 9.8 M [N]. The environment in which the device reads and writes is mostly 3G or less in a normal use state, and rarely exceeds that. Further, it is said that there is no particular problem as long as it withstands 10 G even under particularly severe conditions in a normal use state.
Therefore, if the pressing force is set to the lower limit or more, the rotor height does not change under the environment of normal operation, and the displacement can be exerted only when there is a large external vibration to exert the vibration damping effect. The height of the rotor can be kept constant, and the height of the disk can always be maintained with high accuracy, so that a drive error such as an HDD or an optical disk does not cause a read error due to a defective disk height. On the other hand, the numerical value described in the upper limit value is a relatively large value, and the thrust receiver does not displace in an environment where the device reads and writes. However, even with this high pressing force, the boundary condition of the coupling portion is changed from the conventional fixed support to the free support, whereby the rigidity is reduced and the resonance point is changed. Lower, eg 6G
If the pressing force is not more than equivalent, the displacement is more reliably caused by the instantaneous large pressure due to the external vibration to exert the vibration damping action. In this way, the vibration damping effect can be reliably exerted when necessary, or the resonance point can be changed, and the rotor height can be kept constant during normal times.

Here, how the resonance phenomenon of the device can be reduced in this embodiment and how the noise has been reduced will be described. 5A and 5B show resonance frequency data of the rotor portion of the device, FIG. 5A is a phase diagram of a conventional example, FIG.
(C) is a phase diagram of this embodiment, and (d) is its amplitude diagram.

The difference between the conventional device and the device of the present embodiment is as follows.
8 and FIG. 3, that is, only the vicinity of the thrust receiver. The resonance frequency of the conventional rotor is shown in FIGS.
As shown in FIG. 5B, the resonance point is at 920 Hz, but in this embodiment, the resonance point is shifted to 620 Hz as can be seen from FIGS. 5C and 5D. As a result, the noise of the device has reached 40 dB (A) with its peak being close to the resonance frequency (about 900 Hz) of the housing in the past, but has been reduced to 23 dB (A) in the present embodiment. The background noise at this time was 21 to 22 dB (A).

(Embodiment 2) Next, a second embodiment of the present invention will be described. FIG. 6 is a partially enlarged sectional view of the bearing mechanism. In the figure, a shaft 31, a thrust receiver 33, and a bottom plate 35 are the same as those in the first embodiment. The sleeve 42 is almost the same, but the thrust direction gap between the thrust receiver and the bottom plate is changed according to the elastic member 44 sandwiched therebetween.

The major difference from the first embodiment is that
That is, the synthetic rubber sheet 44 is used as the elastic pressing means. A rubber-like elastic material such as a synthetic rubber sheet has a high vibration damping property. Even when the thrust receiver 33 does not move in the axial direction, the rubber-like elastic substance is in close contact with the thrust receiver and dampens the vibration propagating therein. Also, no concentrated load is applied to the thrust receiver 33. Therefore, it is resistant to destruction, and is particularly suitable for spindle motors used in severe environments with large external vibration.

(Embodiment 3) A third embodiment of the present invention will be described with reference to FIG. The figure is a partially enlarged sectional view of the bearing mechanism. As can be seen from the figure, the bottom plate 55 also has an elastic pressing function, and the center thereof presses the center of the thrust receiver 33 toward the shaft 31.

With such a structure, when the spherical portion 31a at the tip of the shaft presses the thrust receiver 33 with an extremely large force, such as when the device is dropped, the load is reduced by the bottom plate 5
5 always supports directly below. No large bending stress is generated in the thrust receiver 33. Therefore, even if a brittle material such as a ceramic material is selected for the thrust receiver 33, it is not broken. Further, of course, in a normal operating state, the present invention has a vibration noise reduction effect which is the operation effect of the present invention.

(Embodiment 4) FIG. 8 is a partially enlarged sectional view of a bearing mechanism according to a fourth embodiment of the present invention. In this example, the shaft 31 and the thrust receiver 31 are the same as those of the other embodiments, but the elastic pressing means and the structure for holding it are different.

In this embodiment, an O-ring 64 made of synthetic rubber is used as the elastic pressing member. This O-ring
The sleeve 62 is pressed against the contact surface of the sleeve and at the same time against the inner wall surface of the sleeve by the end portion (the caulking fixing portion) of the sleeve 62. Therefore, the function of preventing the lubricant of the bearing portion from leaking from the gap is exhibited, in addition to the function and effect of the elastically pressing the thrust receiver. Note that an adhesive may be filled instead of the O-ring.

Although several embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various applications and developments are possible within the scope of the present invention. In the embodiment, the description has been made of the shaft rotation type bearing mechanism. However, the present invention can be applied to a shaft fixed type bearing mechanism, and the same effects can be obtained. Magnetic force may be used as the elastic pressing force. For this purpose, a suction force to the shaft side is applied to the thrust receiver or a repulsive force is applied from the opposite direction.

[0048]

As described above, according to the present invention, while the height of the thrust receiver is kept constant, the constant impact force is not excessively increased, and the separating collision motion of the thrust bearing portion can be achieved even in a vibration environment. A small spindle motor can be obtained. As a result, it is possible to obtain a disk drive device free from read / write errors, noise, and reduced bearing life caused by vibration and collision.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing the structure of a disk drive device according to an embodiment of the present invention.

FIG. 2 is a partially enlarged sectional view of the spindle motor.

FIG. 3 is a partially enlarged sectional view of the bearing mechanism.

FIG. 4A is a plan view of a leaf spring disposed behind the thrust receiver, and FIG.

5A is a phase diagram of a conventional example of resonance frequency data of a rotor portion of a device. FIG. 5B is a phase diagram of the present embodiment of resonance frequency data of a rotor portion of a device. FIG. Figure

FIG. 6 is a partially enlarged cross-sectional view of a bearing mechanism according to a second embodiment.

FIG. 7 is a partially enlarged cross-sectional view of a bearing mechanism according to a third embodiment.

FIG. 8 is a partially enlarged sectional view of a bearing mechanism according to a fourth embodiment.

FIG. 9 is a partially enlarged sectional view showing a conventional hydrodynamic bearing mechanism.

FIG. 10 is a sectional view showing another conventional thrust bearing mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Housing 11b Stator holding part 12 Disk 20 Spindle motor 21 Hub 22 Stator assembly 23 Magnet 24 Ring-shaped magnetic plate 30 Bearing assembly 31 Shaft 31a Shaft tip 31b Spherical surface 31b Outer peripheral surface of shaft 32, 42, 52, 62 Sleeve 32a Sleeve 32c Thrust receiving contact surface of sleeve (positioning member) 32c Wall restricting radial movement of thrust receiver 32d Sleeve end (caulking fixed portion) 33 Thrust receiver 33a Shaft-side end face of thrust receiver 33b Thrust Surface opposite to the receiving shaft 34 Disc spring, metal leaf spring (elastic pressing means) 44 Synthetic rubber sheet (elastic pressing means) 35, 55 Bottom plate 64 O-ring (elastic pressing means)

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H02K 5/24 H02K 5/24 B 7/08 7/08 A F-term (Reference) 3J011 AA03 AA20 BA02 BA08 CA02 KA02 KA03 LA05 3J012 AB02 AB07 BB02 CB03 DB08 DB09 DB14 FB01 HB04 5D109 BB05 BB12 BB18 BB21 BB23 BB27 5H605 AA04 AA05 BB05 BB10 BB19 CC04 EB03 EB06 EB19 FF08 GG03 GG01 GG21 GG21 5H607 A03

Claims (7)

[Claims] 1. A shaft, a sleeve surrounding the outer periphery thereof, a thrust receiver for supporting one end of the shaft, and a positioning member which is located on the shaft side of the thrust receiver and axially positions one end of the thrust receiver with respect to the sleeve. A spindle motor having the thrust receiver elastically pressed and held by the positioning member. 2. A shaft, a sleeve surrounding the outer periphery thereof, and a thrust receiver provided at one end of the sleeve and supporting one end of the shaft, wherein the sleeve is arranged so that one end surface on the shaft side of the thrust receiver in an axial direction. A spindle motor having a contact surface for positioning the thrust receiver on the contact surface of the sleeve elastically. 3. The thrust receiver is provided with a mass of the rotating body as M [k
g], the spindle motor according to claim 1, wherein the spindle motor is elastically pressed and held by a force of 3 × 9.8 M to 10 × 9.8 M [N]. 4. The spindle motor according to claim 1, wherein the member that elastically presses the thrust receiver is a metal leaf spring. 5. The spindle motor according to claim 1, wherein the member that elastically presses the thrust receiver is a rubber-like elastic material. 6. The spindle motor according to claim 1, wherein a distance by which the thrust receiver elastically moves in the axial direction is 0.1 mm or less. 7. A disk drive on which the spindle motor according to claim 1 is mounted.