JP2003030921A - Information recording / reproducing device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] A low-cost information recording that can record and reproduce information at a high density by rotating a plane on which an information recording medium layer is formed with reduced surface runout and with high precision. A playback device is provided. SOLUTION: A disk portion having a plane on which an information recording medium layer for recording a plurality of substantially concentric recording tracks is formed, and a rotating shaft portion is integrally formed on a surface opposite to the flat surface, and a center of the rotating shaft portion is formed. By configuring a rotating disk whose axis is the center of rotation, fastening parts for the disk are not required and cost is reduced.Moreover, the perpendicularity between the rotation center and the plane on which the information recording medium layer is formed is made highly accurate, Further, by forming a dynamic pressure generating groove on either the open end side end surface of the bearing sleeve or the lower surface of the rotating disk opposed to the open end side end surface to constitute a thrust bearing portion, the rigidity of the bearing is increased, and a highly accurate disk is formed. Realization of high recording density by realizing surface runout and axial runout.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording / reproducing apparatus using an information recording medium such as a magnetic disk or an optical disk, and more particularly to an apparatus capable of recording information at high density and reproducing it.

[0002]

2. Description of the Related Art A conventional information recording / reproducing apparatus will be described below with reference to the drawings.

FIG. 8 is a schematic sectional view of the structure of the main part taken along the line A--A--A in FIG. 9, and FIG. 9 shows the disk, rotary base, rotary shaft part, rotor yoke, flange part and fastening parts of FIG. It is a schematic plan view from the upper surface of the removed part.

In FIGS. 8 and 9, a rotary shaft portion 82 is fixed to a rotary base 81 by a method such as press fitting, and a plurality of poles are magnetized to a lower surface of a flange portion 83 of the rotary base 81 via a rotor yoke 84. The rotary magnet 85 is fixed, and the rotor 86 is formed by these.

On the other hand, a ring-shaped bearing sleeve 87 having an outer peripheral surface of the rotary shaft portion 82 of the rotor 86 and an inner peripheral surface in which a minute gap is formed is formed with one end sealed by a thrust support plate 88. And is fixed to the base 89, and as shown in a partially enlarged view of FIG.
7 and the thrust support plate 88 in the recess formed in the rotor 8
The rotary shaft portion 82 of No. 6 is inserted, and a dynamic pressure lubricant 90 such as ester synthetic oil is sealed in a minute gap between the rotary shaft portion 82, the bearing sleeve 87 and the thrust support plate 88. Further, a stator 93 in which a coil 92 is wound around an iron core 91 is fixed to a base 89 by a method such as press fitting or bonding, and the rotating magnet 85 and the iron core 91 around which the coil 92 is wound are arranged to face each other. A thrust suction plate 94 is fixed to the base 89 so as to face the lower end surface of the rotary magnet 85 in the axial direction.

A thrust bearing portion 96 is formed with a dynamic pressure generating groove 95 on the upper surface of a thrust support plate 88 facing the lower end surface of the rotary shaft portion 82 of the rotor 86. Also, the rotor 86
A radial bearing portion 97 having a dynamic pressure generating groove (not shown) is formed on the inner peripheral surface of the bearing sleeve 87 which faces the outer peripheral surface of the rotary shaft portion 82 of the thrust bearing portion 96 and the radial bearing portion 97. Thus, a so-called fluid bearing is configured, and as is well known, the rotating magnet 85 is rotated by supplying an electric current to the coil 92, that is, the rotor 86 is rotated, and the rotating shaft portion 82 of the rotor 86 is rotated to move. Dynamic pressure is generated in the pressure lubricant 90, and the rotary shaft portion 82 receives the dynamic pressure in the radial direction and the axial direction, so that the rotor 86 is smoothly rotated around the rotation center 1, and the information recording / reproducing apparatus or the like is provided. A suitable disk drive motor 98 is formed.

A flat surface 801 on which an information recording medium is formed
Disc-shaped recording medium (hereinafter referred to as disc)
802 is mounted on the upper surface of the flange portion 83 of the rotary base 81, and the clamp member 803 fixes the disc 802 by pressing the screw 804 against the flange portion 83 of the rotary base 81. Disk 802 by motor 98
The disk 802 is rotated by a known method using an information conversion element such as a magnetic head (not shown) mounted on a slider or an optical pickup (not shown) equipped with an objective lens for condensing light by rotating the disk. An information recording / reproducing apparatus is configured by performing recording / reproducing on / from.

[0008]

In recent years, various information devices have been widely used, and there is an increasing need to increase the recording capacity of disks, and efforts to increase recording density have been made. In addition to being strengthened, the demand for smaller and thinner devices is increasing. Along with this, it has become necessary to improve the rotational accuracy of the disk and reduce the cost.

However, in the information recording / reproducing apparatus in which the disk is mounted on the rotary base of the disk drive motor having the above-described conventional structure, the surface runout of the flange of the rotary base and the disk and the axial center runout with respect to the center of rotation are as follows. Appearing in superposed form, it is very difficult to keep the dynamic surface runout and shaft runout of the rotating disk small, and it is necessary to manufacture each runout and shaft runout with extremely high precision. Further, there is a problem in that a fastening component for fixing the disc to the rotary table is required, resulting in an increase in cost.

The present invention solves the above-mentioned problems, forms a rotary disk in which the disk and the rotary shaft of a disk drive motor are integrally formed, and further, the open end side end surface of the bearing sleeve and the rotary disk facing it. By forming the thrust bearing part on the bottom surface, it is possible to realize downsizing and thinning, and also to achieve high-precision disk surface runout and shaft center runout to achieve high recording density. An object of the present invention is to provide an information recording / reproducing apparatus capable of reducing costs by deleting parts.

[0011]

In order to achieve this object, an information recording / reproducing apparatus of the present invention is a disk portion having an information recording medium layer for recording a plurality of recording tracks on its main surface.
And, having a rotating shaft portion on the surface opposite to the main surface of the disk portion, the central axis of the rotating shaft portion is orthogonal to the main surface of the disk portion,
A radial bearing having a rotating disk as a center of rotation and a bearing sleeve having one end closed, and a dynamic pressure generating groove formed on an inner peripheral surface of the bearing sleeve facing the outer peripheral surface of the rotating shaft portion. Section, a thrust bearing section having a dynamic pressure generating groove on at least one of the open end side end surface of the bearing sleeve and the rotary disk surface facing the open end side end surface of the bearing sleeve, and the main surface of the disk section are opposite. On the side surface,
The motor unit includes a rotary magnet fixed to the rotor yoke and a stator arranged to face the rotary magnet.

With this configuration, the fastening parts between the disc and the motor flange can be omitted, the cost can be reduced, and the perpendicularity of the main surface of the disc on which the information signal is recorded to the rotation center is very highly accurate. Therefore, it is possible to greatly reduce the surface wobbling due to the perpendicularity defect, achieve the highly accurate surface wobbling and axial wobbling of the disc, and realize the information recording / reproducing apparatus that exhibits the excellent effect of the high recording density. be able to.

In order to achieve this object, the information recording / reproducing apparatus of the present invention has a structure in which a rotating disk is integrally formed with a rotating shaft portion and a disk portion having an information recording medium layer on its main surface. .

With this structure, the perpendicularity of the main surface of the disk portion on which the information signal is recorded to the center of rotation becomes more accurate, the surface runout due to the defect of the perpendicularity can be greatly reduced, and the out-of-plane vibration can be achieved. Can be suppressed,
The recording density can be improved. Further, radial deviation with respect to the rotation center can also be suppressed to a small level, and the rotation center of a servo signal pre-transferred for accurately following a plurality of substantially concentric recording tracks on the information signal recording surface of the disk portion. The deviation of the center of rotation during actual operation of the disk unit can be suppressed to a small value, and high recording density can be achieved.

In order to achieve this object, in the information recording / reproducing apparatus of the present invention, the rotating disk has an annular wall portion surrounding the rotating shaft portion on the surface opposite to the main surface of the disk portion, An open end of a bearing sleeve is loosely fitted in an annular groove formed by the shaft portion and the wall portion, and the disk portion is rotatably supported by the thrust bearing portion.

With this structure, it is possible to obtain an effect that the dynamic pressure lubricant can be stably held and excellent performance as a fluid bearing can be exhibited.

In order to achieve this object, the information recording / reproducing apparatus of the present invention is a rotary disk having a lubricant reservoir formed on the inner peripheral surface of the annular wall of the rotary disk facing the outer peripheral surface of the bearing sleeve. Have a configuration.

With this structure, it is possible to prevent the dynamic pressure lubricant from flowing out, hold the dynamic pressure lubricant stably for a long period of time, and obtain the effect that stable performance as a fluid bearing can be exhibited. .

To achieve this object, the information recording / reproducing apparatus of the present invention has a structure in which a lubricant reservoir is formed on the inner peripheral surface of the annular wall of the rotor yoke which faces the outer peripheral surface of the bearing sleeve. .

With this configuration, it is possible to prevent the dynamic pressure lubricant from flowing out, and obtain an effect that stable performance as a fluid bearing can be exhibited.

To achieve this object, the information recording / reproducing apparatus of the present invention has a structure in which a lubricant reservoir is formed on the outer peripheral surface of the bearing sleeve.

With this configuration, it is possible to obtain the effects that the dynamic pressure lubricant can be prevented from flowing out, the durability performance of the fluid bearing can be improved, and stable performance can be exhibited.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 and FIG. 2 are schematic configuration diagrams of a main part of an information recording / reproducing apparatus showing Embodiment 1 of the present invention. FIG. FIG. 2 is a schematic cross-sectional view taken along a line, and FIG. 2 is a schematic plan view of the portion of FIG. 1 from which the rotary disk and the rotor yoke are removed, as seen from the upper surface. 1 and 2, the center of rotation 1
A disk portion 4 having an information recording medium layer 3 formed on a main surface 2 perpendicular to the axial direction and a rotary disk 6 having a solid cylindrical rotation shaft portion 5 integrally formed on the side opposite to the main surface 2. Has been formed. The disc portion 4 and the rotary shaft portion 5 may be formed integrally by separately forming members by a method such as integral formation, adhesion with an adhesive, or heat fusion. A trough-shaped ring-shaped bearing sleeve 7 having one end sealed with an outer peripheral surface of the rotary shaft portion 5 of the rotary disk 6 and an inner peripheral surface forming a minute gap is fixed to a base 8. As shown in a partially enlarged view, the rotary shaft portion 5 of the rotary disk 6 is inserted into the concave portion of the bearing sleeve 7, and a minute gap between the rotary shaft portion 5 and the bearing sleeve 7 and at least the bearing sleeve 7 are formed. In the minute gap between the open end side end surface 7a and the surface of the rotating disk 6 on which the rotating shaft portion 5 is formed (hereinafter referred to as the lower surface of the rotating disk),
For example, a dynamic pressure lubricant 31 such as ester synthetic oil is enclosed. Further, a rotor yoke 9 is fixed to a surface of the rotating disk 6 opposite to the main surface 2 of the disk portion 4, that is, a surface on the rotating shaft portion 5 side, and a ring-shaped rotating magnet 10 magnetized to a plurality of poles is bonded to the rotor yoke 9. And the like. On the other hand, the stator 13 in which the coil 12 is wound around each of the plurality of magnetic pole teeth of the iron core 11 is fixed to the base 8 by a method such as press fitting, and the rotary magnet 10 and the coil 1 are
The iron cores 11 on which 2 are wound are arranged so as to face each other. A thrust suction plate 14 made of a soft magnetic material is fixed to the base 8 so as to face the lower end surface of the rotary magnet 10 in the axial direction.

The end surface 7a of the bearing sleeve 7 facing the lower surface of the rotary disk 6 has a dynamic pressure generating groove 21 as shown in FIG. 2 and forms a thrust bearing portion 32 in FIG. Further, a radial bearing portion 33 having a dynamic pressure generating groove (not shown) is formed on the inner peripheral surface of the bearing sleeve 7 facing the outer peripheral surface of the rotary shaft portion 5 of the rotary disk 6, and a current is supplied to the coil 12. As is well known, the rotation causes the rotating magnet 10 to rotate, that is, the rotating disk 6 to rotate, and the rotation of the rotating shaft portion 5 generates a dynamic pressure in the dynamic pressure lubricant 31, which causes the bearing sleeve 7 and the rotating disk 6 to be radially rotated. The rotary disk 6 is smoothly rotated around the rotation center 1 by receiving the dynamic pressure in the axial direction and the axial direction.

The bearing sleeve 7 is used as the thrust bearing portion 32.
Since the dynamic pressure generating groove 21 is formed on the end face 7a on the open end side, the conventional example in which the dynamic pressure generating groove 95 is formed as the thrust bearing portion 96 on the upper surface of the thrust support plate 88 (FIGS. 9 and 1).
(See 0), it becomes relatively easy to integrally manufacture the trough-shaped bearing sleeve having the dynamic pressure generating groove 41,
Unlike the conventional example, the thrust support plate 88 is not required individually, which is effective in reducing the cost, and the dynamic pressure generating groove 41 is also available.
It is relatively easy to increase the surface area for forming the groove, and the position where the dynamic pressure generating groove 41 is formed has a larger radial distance from the center of rotation than the conventional example, and the bearing rigidity as the thrust bearing portion is high. It is possible to form a thrust bearing portion which is high and has stable operation.

The thrust suction plate 14 is provided so as to face the lower end surface of the rotary magnet 10, and the dynamic pressure lubricant 31 is filled in the gap formed by the recess of the bearing sleeve 7 and the rotary shaft 5 of the rotary disk 6. By doing so, regardless of any attitude difference of the information recording / reproducing apparatus, the rotating shaft portion 5 of the rotating disk 6 is caused to have a magnetic force between the rotating magnet 10 and the thrust attraction plate 14 and an atmospheric pressure around the rotating disk 6. Therefore, the dynamic pressure lubricant 31 does not come off from the recess of the bearing sleeve 7, and the dynamic pressure lubricant 31 does not flow out due to the viscosity and surface tension of the dynamic pressure lubricant 31 itself, and the dynamic pressure lubricant 31 disappears.
Even during the rotation of the rotary disk 6, the dynamic pressure of the generated dynamic pressure lubricant 31 and the self-weight of the rotary disk 6, the magnetic force between the rotary magnet 10 and the thrust suction plate 14, and the atmospheric pressure around it are smooth in a balanced state. It is something that rotates.

The dynamic pressure generating groove 41 is not formed on the open end side end surface 7a of the bearing sleeve 7 which faces the lower surface of the rotary disk 6 in the above-described embodiment (FIGS. 1, 2 and 3). Instead, as shown in FIG. 4 (a schematic plan view seen from the side opposite to the main surface of the rotary disk in FIG. 1), the dynamic pressure is applied to the portion of the lower surface of the rotary disk 6 facing the open end side end surface 7a of the bearing sleeve 7. It goes without saying that the same effect can be obtained by forming the generating groove 41.
Are formed in the same shape as the dynamic pressure generating groove 41 formed on the open end side end surface 7 a of the bearing sleeve 7. Further, the dynamic pressure generating groove 41 forming the radial bearing portion may be formed not on the inner peripheral surface of the bearing sleeve 7 but on the outer peripheral surface of the rotating shaft portion 5 facing the inner peripheral surface of the bearing sleeve 7 as described above. good.

Further, as shown in FIG. 5A, the annular wall portion 51a of the rotor yoke 51 facing the outer peripheral surface of the bearing sleeve 7 or, as shown in FIG. 5B, the annular wall portion of the rotor yoke 9. 9a, a ring-shaped lubricant reservoir 53 is formed on the outer peripheral surface of the bearing sleeve 52 which faces 9a, or FIG.
As shown in (c), the ring-shaped annular wall portion 5 having the ring-shaped lubricant reservoir 55 on the lower surface of the rotating disk 54 so that the outer peripheral surface of the bearing sleeve 52 has a minute gap.
4a may be formed so that the dynamic pressure lubricant 31 does not flow out along the outer peripheral surface of the bearing sleeve 52. In the figure, the lubricant reservoir 53 or 55 is shown as having a triangular cross section, but the lubricant reservoir 53 or 55 is not limited to this shape, and may have an arc shape or another shape.

In the above embodiment, the inside of the iron core 11 around which the coil 12 is wound (on the side of the rotation center 1) is
Although a so-called inner rotor type configuration in which the rotary magnet 10 fixed to the rotor yoke 9 is configured to face the iron core 11 has been described, as shown in FIG. 6, the iron core 62 around which the coil 61 is wound is the rotor yoke 63. It goes without saying that a so-called outer rotor type configuration may be used which is configured to face the inside of the rotary magnet 64 fixed to the. Note that, in FIG. 6, the same reference numerals as those in FIG. 1 are added to the same items to which the reference numerals shown in FIG. In FIG. 6, an iron core 62 around which a coil 61 is wound is fixed to a bearing sleeve 65 by a method such as press fitting or bonding, while a rotating magnet 64 fixed to a rotor yoke 63 is bonded to a rotating disk 66. The core 62 and the rotating magnet 64 are fixed so as to face each other. The other points are the same as those of the inner rotor type in FIG. 1, and detailed description thereof is omitted here. The iron core 62 may be fixed to the base 67 by a method such as adhesion.

Further, although the above-mentioned embodiment is shown as a so-called radial gap (circumferentially facing) type brushless motor, as shown in FIG. 7, a so-called axial gap (face-facing) type brushless motor is structured. It goes without saying that it may be formed by. Here, FIG. 7 is a schematic sectional view showing an example of a main part of an information recording / reproducing apparatus having a structure of an axial gap type brushless motor. The same reference numerals as those in FIG. 1 are attached to the same items as those to which the reference numerals shown in FIG. 1 are added.
In FIG. 7, the information recording medium layer 3 is formed on the main surface 2 perpendicular to the axial direction of the rotation center 1, and the disk portion 71 having the annular wall portion 71a on the surface opposite to the main surface and the main surface 2 are A rotary disk 72 having the rotary shaft portion 5 integrally formed on the opposite surface is formed. On the other hand, the rotary shaft portion 5 of the rotary disk 72 is formed.
A trough-shaped ring-shaped bearing sleeve 73 having one end sealed with an outer peripheral surface and an inner peripheral surface where a minute gap is formed is fixed to a base 74. Dynamic pressure generating grooves are formed in the open end side end surface 73a of the bearing sleeve 73 and the inner peripheral surface of the bearing sleeve 73, and the rotary disk 72 and the bearing sleeve 73 are formed.
The structure in which the dynamic pressure lubricant 75 is enclosed in the minute gap between the two is the same as the structure having the radial gap type brushless motor described above. The difference from this is that, as shown in FIG. 7, the rotor yoke 76 is provided on the surface of the disk portion 71 of the rotary disk 72 opposite to the main surface 2, that is, on the rotary shaft portion 5 side.
Are fixed by a method such as adhesion, and a ring-shaped rotary magnet 77 magnetized to have a plurality of poles is similarly fixed by a method such as adhesion on the rotor yoke 76. A plurality of triangular coils 7
The stator 70 wound with 9 is fixed to the base 74,
That is, the rotary magnet 77 and the coil 79 are arranged so as to face each other with a gap in the axial direction.

Further, in each of the above-described embodiments (inner rotor type, outer rotor type and axial gap type in radial gap type), a dynamic pressure lubricant is applied to the concave portion of the bearing sleeve at the time of assembly in a vacuum such as a vacuum tank. It is preferable to drop a predetermined amount and then insert the rotating shaft portion of the rotating disk into the recess of the bearing sleeve. By assembling in a vacuum, bubbles such as air contained in the dynamic pressure lubricant are removed. Furthermore, since the dynamic pressure lubricant does not contain air bubbles such as air, the air bubbles do not expand due to the ambient temperature during operation, so that more stable bearing performance can be exhibited.

As described above, according to the first embodiment, the information signal is transmitted by forming the disk portion having the information recording medium layer on the main surface and the rotary shaft portion integrally or integrally. The perpendicularity to the center of rotation of the main surface of the recorded disc is much higher than that of the conventional example in which the disc is coupled to the flange of the rotary base of the disc drive motor. The shake can be greatly reduced, out-of-plane vibration can be suppressed, and the recording density can be improved. Also, radial runout with respect to the center of rotation can be suppressed to a small level,
The discrepancy between the rotation center of the pre-transferred servo signal and the rotation center during the actual operation of the disc portion for accurately following a plurality of recording tracks of substantially concentric circles on the information signal recording surface of the disc portion can be suppressed. Therefore, high recording density can be realized. Also, by making the rotating disk double as a part of the rotor of the disk drive motor, the member that clamps the disk to the flange of the disk of the disk drive motor and the rotary table itself become unnecessary, and low cost is achieved. It is possible to reduce the thickness and at the same time reduce the thickness. Further, by forming a dynamic pressure generating groove on either the open end side end surface of the bearing sleeve or the lower surface of the rotating disk facing the open end side end surface to form the thrust bearing portion, the thrust bearing portion of the conventional example can be formed. The thrust support plate can be omitted, and cost reduction can be realized. Further, since the thrust bearing portion is formed at a position that is larger in the radial direction with respect to the center of rotation with respect to the conventional thrust shaft portion, the bearing rigidity of the thrust bearing portion is increased and the extremely high precision disc Surface wobbling can be realized, and high recording density can be realized.

[0034]

As described above, according to the present invention, the disk portion having the information recording medium layer on the main surface thereof has the rotation axis whose central axis is orthogonal to the main surface on the surface opposite to the main surface of the disk portion. A radial bearing part having a dynamic pressure generating groove in the inner circumference of a trough-shaped substantially cylindrical bearing sleeve that forms a rotary disc with integrated parts, and one of which faces the outer peripheral surface of the rotary shaft part is sealed. By forming a thrust bearing portion having a dynamic pressure generating groove on at least one of the open end side end surface and the outer peripheral surface of the rotary shaft portion of the rotating disk facing the bearing sleeve open end side end surface, an information signal for the rotation center is formed. The perpendicularity of the main surface of the disc part where is recorded is very accurate,
It is possible to greatly reduce the surface runout due to the perpendicularity defect, suppress the out-of-plane vibration, and improve the recording density. Further, radial deviation with respect to the rotation center can also be suppressed to a small level, and the rotation center of a servo signal pre-transferred for accurately following a plurality of substantially concentric recording tracks on the information signal recording surface of the disk portion. The deviation of the center of rotation during actual operation of the disk unit can be suppressed to a small value, and high recording density can be achieved.

Further, by making the rotary disk also serve as a part of the rotor of the disk drive motor, a member for clamping the disk on the flange portion of the rotary table of the disk drive motor and the rotary table itself are unnecessary, The cost can be reduced and the thickness can be reduced. Further, since the thrust bearing portion is formed at a position distant from the center of rotation in the radial direction, the bearing rigidity of the thrust bearing portion is increased, and very highly accurate surface wobbling and axial wobbling of the disk are realized. Therefore, an effect that a high recording density can be achieved can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view for explaining an outline of a configuration of a main part of an information recording / reproducing apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic plan view for explaining an outline of a configuration of a main part of the information recording / reproducing apparatus according to the first embodiment of the present invention.

FIG. 3 is a partially enlarged view for schematically explaining the configuration of a main part of the information recording / reproducing apparatus according to the first embodiment of the present invention.

FIG. 4 is a schematic plan view showing another example of the information recording / reproducing apparatus in the first embodiment of the present invention.

5A is a partially enlarged view showing another example of the shape of the rotor yoke according to the first embodiment of the present invention. FIG. 5B is a partially enlarged view showing another example of the shape of the bearing sleeve according to the first embodiment of the present invention. FIG. 6C is a partially enlarged view showing another example of the shape of the rotating disk according to the first embodiment of the present invention.

FIG. 6 is a schematic sectional view showing an example of an outer rotor type according to Embodiment 1 of the present invention.

FIG. 7 is a schematic cross-sectional view showing a configuration of a main part of an information recording / reproducing apparatus having the configuration of the axial gap type brushless motor according to the first embodiment of the present invention.

FIG. 8 is a schematic cross-sectional view showing a configuration of a main part of a conventional information recording / reproducing apparatus.

FIG. 9 is a schematic plan view showing the configuration of the main part of a conventional information recording / reproducing apparatus.

FIG. 10 is a partially enlarged view for explaining the structure of a conventional information recording / reproducing apparatus.

[Explanation of symbols]

1 rotation center 2 main surface 3 Information recording medium layer 4,71 Disc part 5 rotating shaft 6,54,66,72 rotating disk 7,52,65,73,87 Bearing sleeve 7a, 73a Open end side end face 8,67,74,89 base 9,51,63,76,84 Rotor yoke 9a, 51a, 54a, 71a Annular wall part 10, 64, 77, 85 rotating magnet 11,62,91 iron core 12, 61, 79, 92 coils 13, 70, 93 Stator 14,94 Thrust suction plate 31,75,90 Dynamic pressure lubricant 21, 41, 95 Dynamic pressure generation groove 32,96 thrust bearing 33,97 radial bearing 53,55 Lubricant reservoir 78 Printed circuit board 81 turntable 82 Rotating shaft 83 Flange 86 rotor 88 Thrust support plate 98 motor 801 plane 802 Disc-shaped recording medium (disc) 803 Clamp member 804 screw

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H02K 21/14 H02K 21/14 MF term (reference) 3J011 AA02 BA04 CA02 KA02 KA03 5D006 CB07 DA03 DA05 5D109 AA08 BA15 BA17 BA22 BB06 BB17 5H607 AA04 BB01 BB07 BB14 CC09 DD03 DD05 GG02 GG15 5H621 BB07 GA02 HH02 JK08 JK17 JK19

Claims (6)

[Claims] 1. A disk portion having an information recording medium layer for recording a plurality of recording tracks on a main surface, and a rotation shaft portion on a surface opposite to the main surface of the disk portion, The central axis of the shaft portion is orthogonal to the main surface of the disc portion, and has a rotating disc that serves as a center of rotation, and a bearing sleeve whose one end is closed, and faces the outer peripheral surface of the rotating shaft portion. A radial bearing portion in which a dynamic pressure generating groove is formed on the inner peripheral surface of the bearing sleeve, and at least one of the open end side end surface of the bearing sleeve and the rotating disk surface facing the open end side end surface of the bearing sleeve. A thrust bearing portion having a groove for generating a dynamic pressure, a rotary magnet fixed to a rotor yoke on a surface of the disk portion opposite to the main surface, and a stator arranged to face the rotary magnet. Constitution Information recording and reproducing apparatus characterized by comprising a motor portion to be. 2. The information recording / reproducing apparatus according to claim 1, wherein the rotating disc is formed integrally with the rotating shaft portion and the disc portion having an information recording medium layer on a main surface thereof. 3. The rotating disk has an annular wall portion surrounding the rotating shaft portion on a surface of the disk portion opposite to the main surface, and is formed by the rotating shaft portion and the annular wall portion. The open end portion of the bearing sleeve is loosely fitted in an annular groove portion, and the disk portion is rotatably supported by the thrust bearing portion. Information recording / reproducing apparatus described. 4. The information recording / reproducing apparatus according to claim 3, wherein a lubricant reservoir is provided on an inner peripheral surface of the annular wall portion of the rotary disk facing the outer peripheral surface of the bearing sleeve. 5. The information according to claim 1, further comprising a lubricant reservoir portion on an inner peripheral surface of an annular wall portion of the rotor yoke which faces an outer peripheral surface of the bearing sleeve. Recording / playback device. 6. The information recording / reproducing apparatus according to claim 1, further comprising a lubricant reservoir on the outer peripheral surface of the bearing sleeve.