JP2000076827A - Hard disc device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect the internal mechanism of a hard disc device and record/ reproduce proper information signals in/from a disc-type recording medium. SOLUTION: A hard disc device 1 has a disc-type recording medium 6, a spindle motor 5 which turns the disc-type recording medium 6, heads 21 and 21 by which information signals are recorded/reproduced in/from the disc-type recording medium 6 and an actuator 7 to which the heads are attached and which is transferred to position the heads at arbitrary positions of recording tracks of the disc-type recording medium. The spindle motor, the disc-type recording medium and the actuator are placed in an outer housing 2 composed of a housing 3 and a cover 4 covering the housing 4. The axial direction of the spindle motor is perpendicular to the surface direction of the cover and the spindle motor has a non-rotating part 10 fixed to the inside of the outer housing and a rotating part 12 which is rotatably supported by the non-rotating part 10. A spacing between the cover and the non-rotating part is smaller than a spacing between the cover and the rotating part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a hard disk drive. More specifically, the present invention relates to a technique for protecting an internal mechanism of a hard disk device and ensuring a proper information signal recording and reproducing operation on a disk-shaped recording medium.

[0002]

2. Description of the Related Art In recent years, the use of hard disk drives has expanded, and in addition to large-sized recording apparatuses and recording apparatuses for desktop personal computers, for example, notebook personal computers and portable computers of smaller sizes have been used. It is being used for terminals. In recent years, an IC (Integrated Circuit) memory card called a PC (Personal Computer) card size or a PC card type hard disk device having a size about the size of a card type modem has been used. Is used as needed by a user by inserting and removing it from a PC card slot of a notebook personal computer or a portable terminal.

FIGS. 7 to 9 show an outline of such a conventional hard disk drive of the PC card type.

In the hard disk drive a, a bottom cover b having a shallow dish shape and a top cover c having a shape such that the shallow dish is turned down are coupled with a chassis d interposed therebetween. Each mechanism is provided.
The circuit board e is disposed between the chassis d and the bottom cover b, that is, below the chassis d.

[0005] The chassis d has various necessary members and mechanisms,
That is, a spindle motor f, a rotary actuator g, and the like are provided. An annular support portion h is provided upright at a substantially central portion of the chassis d (see FIG. 9).

The spindle motor f has a rotor member i rotatably supported via ball bearings j, j (see FIG. 9).

The rotor member i has a disk-shaped cover portion k positioned so as to cover the ball bearings j, j and the support portion h from above, and a shaft portion l projecting downward from the center of the cover portion k.
And a protruding portion m protruding from the peripheral edge of the cover portion k are integrally formed, and the upper surface of the cover portion k and the lower surface of the top cover c are located at a predetermined small interval. A substantially annular disk clamper n is attached to a portion of the protruding portion m near the outer periphery, and a disc-shaped recording medium o is formed by the outer peripheral portion of the disc clamper n and the outer peripheral portion of the protruding portion m. , The disk-shaped recording medium o is attached to the rotor member i of the spindle motor f.

A rotor magnet p is fixed to the inner surface of the lower end of the protruding portion m of the rotor member i, and a stator member q and stator coils r, r,. Is attached.

The rotary actuator g includes a rotary portion s and a driving portion for rotating the rotary portion s, that is, a coil (not shown), a magnet (not shown) and yokes t, t (only the upper one shown in FIG. 8). Shown).

The rotating portion s includes a supported portion v supported by a support shaft u erected on a chassis d, and protruding portions w, w (FIG. 8) which are respectively protruded vertically apart from the supported portion v. Only the upper one is shown) and heads x, x (only the upper one is shown in FIG. 8) provided at the tip of the protruding parts w, w. The projections w and w have a floating head slider that floats on the disk-shaped recording medium o when the disk-shaped recording medium o is rotated. As shown in FIG. 8, the rotary actuator g is rotatably supported by the support shaft u such that the upper surface of the supported portion v covers the upper surface of the support shaft u.

In the rotary actuator g, the rotary portion s is swung by the electromagnetic force generated between the coil and the magnet, and the heads x and x are positioned on any tracks of the disk-shaped recording medium o, and the information signals Recording or reproduction is performed.

Also, some hard disk drives are equipped with a so-called direct bearing motor as a spindle motor, which can improve motor efficiency and reduce the number of parts (see FIG. 10).

A spindle motor (direct bearing motor) fa of the hard disk drive aa shown in FIG.
The lower end of the motor shaft la is fixed to the chassis d, and the upper half of the motor shaft la is the lower half (excluding the lower end).
The diameter is smaller than that of. A tubular inner ring member y is fitted to the upper half.

The rotor member ia has a substantially cylindrical shape and is rotatably supported on a motor shaft la via balls z, z,.... The motor shaft la, the inner ring member y, and the balls z, z,... Are provided on the upper surface of the central portion of the rotor member ia.
Is attached.

[0015]

In recent years, in order to further reduce the thickness of the hard disk drives a and aa, the bottom cover b and the top cover c are both thinned, or the top cover c and the rotor The gap A (see FIG. 9) or the gap B (see FIG. 10) between the member i and the rotor member ia is reduced.

However, when any external force (load) is applied to the hard disk drives a, aa, the top cover c is bent, and there is a great risk that the top cover c will come into contact with the rotor member i and the rotor member ia at the portion A in the figure. Become.

Such contact is caused by the spindle motors f and fa
There is no problem if this occurs when the motor stops, but when the spindle motors f and fa are rotating, that is, the heads x and x of the rotary actuator g are recording or reproducing information signals. In such a case, a recording error or a reproduction error occurs due to a variation in the rotation of the spindle motors f and fa. In the worst case, the rotation speed of the spindle motors f and fa decreases, and the head slider of the rotary actuator g is reduced. There is a danger that the flying height decreases and the disk-shaped recording medium o is damaged by the contact of the heads x, x with the disk-shaped recording medium o.

Normally, the spindle motors f and fa are arranged at the center of the hard disk drives a and aa where the amount of deflection when a load P is applied is large as shown in FIG. The contact described above is particularly problematic.

Similarly, hard disk devices a, a
When some external force (load) is applied to the top cover a and the top cover c bends, the top cover c comes into contact with the upper surface of the supported portion v of the rotary actuator g and hinders proper operation of the rotary actuator g. Also, a recording error or a reproduction error may occur.

SUMMARY OF THE INVENTION It is an object of the present invention to protect the internal mechanism of a hard disk device and to ensure proper recording and reproduction of information signals on a disk-shaped recording medium.

[0021]

In order to solve the above-mentioned problems, a hard disk drive according to the present invention comprises a spindle motor and a disk-shaped recording medium in an outer housing formed by a housing and a cover covering the housing. And an actuator are arranged, and the spindle motor has a non-rotating part whose axial direction is orthogonal to the surface direction of the cover body and is fixed in the outer casing, and a rotating part rotatably supported by the non-rotating part. In the hard disk drive, the distance between the cover and the non-rotating portion is smaller than the distance between the cover and the rotating portion.

Therefore, in the hard disk drive of the present invention, when a load is applied to the cover, the cover does not contact the rotating part.

Another hard disk drive of the present invention is:
To solve the above-described problem, a spindle motor, a disk-shaped recording medium, and an actuator are arranged in an outer case formed by a case and a cover body that covers the case,
In a hard disk drive, the actuator has a non-rotating part whose axial direction is orthogonal to the surface direction of the cover body and is fixed in the outer casing, and a turning part rotatably supported by the non-rotating part. The distance between the cover and the non-rotating portion is smaller than the distance between the cover and the rotating portion.

Therefore, in another hard disk drive of the present invention, when a load is applied to the cover, the cover does not contact the rotating portion.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the hard disk drive of the present invention will be described with reference to the accompanying drawings.

The hard disk device 1 is used by being mounted on a PC card slot of a notebook personal computer.

The hard disk drive 1 has an outer housing 2 in which a cover 4 is connected to a housing 3.

The housing 3 has a shallow dish shape, and has a mounting hole 3a formed substantially at the center (see FIG. 2).

The cover 4 has a shape as if a shallow dish is laid down, and is attached to the housing 3 so as to cover the upper surface of the housing 3. When the cover body 4 is attached to the housing 3, the outer housing 2 is mounted.
A spindle motor 5, a disk-shaped recording medium 6, a rotary actuator 7, and the like are arranged in the arrangement space 2a.

The spindle motor 5 comprises a base portion 8 and a main body portion 9 attached to the base portion 8 (see FIG. 3). The base portion 8 includes a concave portion 8a opened upward and a flange portion 8b protruding from the periphery of the upper end of the concave portion 8a. Are formed integrally, and the recess 8
The outer diameter of a is the same as the diameter of the mounting hole 3 a of the housing 3.

The main body 7 is a motor shaft 1 as a non-rotating part.
0, ball bearings 11 and 11, a rotor member 12 as a rotating part, and a stator member 13 (see FIG. 3).

The lower end of the motor shaft 10 is
Is fixed to the center portion of the base member by appropriate means such as caulking or bonding. Two ball bearings 11 and 11 are vertically arranged on the motor shaft 10 so as to be externally fitted, and a rotor member 12 is further externally fitted to the ball bearings 11 and 11.

The rotor member 12 includes a ball bearing 11,
A supported portion 12a which is rotatably supported by the motor shaft 10 via 11 and which has a substantially cylindrical shape and is in contact with the ball bearings 11, 11, and a clamper which protrudes outward from a position near the upper end of the supported portion 12a. A portion 12b, a disk mounting portion 12c protruding from a lower edge of the clamper mounting portion 12b, and a rotor case portion 12d protruding downward from an outer edge of the disk mounting portion 12c are integrally formed.

The upper surface of the supported portion 12a and the upper surface of the upper ball bearing 11 are located in the same plane, and the motor shaft 10 projects slightly upward from the upper surface of the upper ball bearing 11.

Accordingly, the distance L1 between the cover 4 and the motor shaft 10 is smaller than the distance L2 between the cover 4 and the uppermost surface of the rotor member 12 (see FIG. 3).

A rotor magnet 14 is fixed inside the rotor case 12d.

An annular mounting portion 8c is erected at a position near the center of the concave portion 8a of the base portion 8, and the mounting portion 8c is positioned so as to surround the lower end of the supported portion 12a of the rotor member 12. The stator member 13 is attached to the attachment portion 8c so as to be fitted to the outside, and the stator coils 13a, 13a,.

The base 8 has a recess 8 a formed in the housing 3.
And the flange portion 8b is attached to the housing 3 with the flange portion 8b in contact with the upper opening edge of the attachment hole 3a. Therefore, the motor shaft 10 is fixed to the housing 3 via the base 8.

The inner peripheral edge of the disk-shaped recording medium 6 is placed on the disk mounting portion 12c with its center hole 6a fitted outside the clamper mounting portion 12b of the rotor member 12. The disk-shaped recording medium 6 placed on the disk mounting portion 12c by the outer end of the disk clamper 15 mounted on the upper surface of the clamper mounting portion 12b of the rotor member 12.
Of the rotor member 1 while the disk-shaped recording medium 6 is held between the disk mounting portion 12c of the rotor member 12 and the disk clamper 15.
2 attached.

The disk-shaped recording medium 6 is attached to the rotor member 12 of the spindle motor 5 as described above.
It is rotated in a predetermined direction with the rotation of the spindle motor 5.

The rotary actuator 7 includes a rotary unit 16 and a driving unit for rotating the rotary unit 16, that is, the coil 1.
7, magnets 18u, 18d and yokes 19u, 19
d (see FIGS. 1 and 2).

The rotating portion 16 is a supported portion 16a supported by a support shaft 20 formed upright on the housing 3 and formed as a non-rotating portion.
And the arm portions 16b, 16b, which are vertically separated from the supported portion 16 and respectively protrude to the side, and the arm portions 16b,
The suspensions 16c, 16c protruding from the suspension 16c, the floating head sliders 16d, 16d continuous with the suspensions 16c, 16c, and the coil mounting portions 16e, 16e protruding from the supported portion 16a in a direction substantially opposite to the arms 16b, 16b. Consists of The heads 21, 21 are attached to the tips of the floating head sliders 16d, 16d. A coil 17 is mounted on the coil mounting portions 16e.

In the rotary actuator 7, the support shaft 20 slightly protrudes upward from the upper surface of the supported portion 12a of the rotary portion 16, so that the distance L3 between the cover body 4 and the support shaft 20 is equal to L3.
Is smaller than the distance L4 between the cover 4 and the rotating portion 16 (see FIG. 4).

The magnet 18u and the yoke 19u, and the magnet 18d and the yoke 19d are integrally formed (see FIG. 2). The magnet 18d and the yoke 19d are attached to the housing 3, and the yoke 19u is separated above the yoke 19d. Attached to this in state. And
The magnet 18u and the magnet 18d are respectively located above and below the coil 17 of the rotary actuator 7 with a predetermined interval.

In the rotary actuator 7, the rotary portion 16 is swung by the electromagnetic force generated between the coil 17 and the magnets 18u and 18d, and the heads 21 and 21 are positioned on any tracks of the disk-shaped recording medium 6. The recording or reproduction of the information signal is performed.

A printed circuit board 22 is mounted on the inner surface of the housing 3, and the printed circuit board 22 is located below the disk-shaped recording medium 6 mounted on the spindle motor 5 except for an extended portion described later.

The printed circuit board 22 is a so-called flexible printed circuit board having a high degree of flexibility, and includes an attached portion 23 attached to the housing 3 and an extended portion 2 extending from the attached portion 23.
4 are formed integrally with each other, and the mounting portion 23 has an arrangement hole 23a at a substantially central portion thereof. The arrangement hole 23 a is formed slightly larger than the outer diameter of the base 8 of the spindle motor 5.

The required ICs 25, 25,
... are mounted. An I / O connector 26 for electrical connection with a personal computer to which the hard disk device 1 is mounted is attached to one end of the attached portion 23.

The extending portion 24 is bent so as to be substantially perpendicular to the attached portion 23, and the tip 24 a is attached to a part of the rotary actuator 7. Then, a required current is supplied to the coil 17 of the rotary actuator 7 via the extension 24.

FIG. 5 shows a hard disk drive 1 using a direct bearing motor 5A as a spindle motor. In addition, this direct bearing motor 5A
In the description of the first embodiment, the same members as those of the spindle motor 5 described above are denoted by the same reference numerals as those of the spindle motor 5, and the description thereof is omitted.

The main body 9A of the spindle motor (direct bearing motor) 5A comprises a motor shaft 10A, inner ring members 5a, balls 5b, 5b,..., A rotor member 12A and a stator member 13.

The upper half of the motor shaft 10A has a smaller diameter than the lower half, and a cylindrical inner ring member 5a is fitted on the upper half.

The rotor member 12A has a substantially cylindrical shape and is rotatably supported on the motor shaft 10A via balls 5b, 5b,.... The inner ring member 5a and the balls 5b, 5b,...
The annular seal cover 5c is attached so as to cover. The motor shaft 10A is inserted through the center hole 5d of the seal cover 5c and protrudes upward.

Therefore, the distance L5 between the cover 4 and the motor shaft 10A is smaller than the distance L6 between the cover 4 and the uppermost surface of the rotor member 12A.

Although a small gap is formed between the seal cover 5c and the motor shaft 10A to maintain proper rotation of the rotor member 12A, the flow of air generated by the rotation of the spindle motor 5A is rotated. Since the dust is generated from the center to the outside, there is almost no possibility that dust enters the gap.

As described above, in the hard disk drive 1, the distance L1 (L5) between the cover 4 and the motor shaft 10 (10A) is determined by the distance between the cover 4 and the rotor member 12.
The distance L2 (L6) from the uppermost surface of (12A) is made smaller.

Therefore, even if the cover 4 is bent by some external force (load) when the hard disk drive 1 is driven, the motor shaft 10 (10A) which is a fixed member fixed to the housing 3 ) And does not come into contact with the rotor member 12 (12A), which is a member on the rotating side. As a result, the spindle motor 5 does not cause a variation in rotation or a decrease in the flying height of the floating head sliders 16d of the rotary actuator 7 due to the variation in rotation. Alternatively, the reproducing operation can be secured.

The cover 4 and the motor shaft 10 (10
A) and the distance L1 (L5) between the cover member 4 and the rotor member 1
The motor shaft 10 (10A) is connected to the rotor member 12 so as to be smaller than the distance L2 (L6) from the uppermost surface of the second member 12 (12A).
It is only necessary to protrude upward from (12A), and it is possible to extremely easily realize the operation of recording or reproducing an appropriate information signal on the disk-shaped recording medium 6.

Further, in the hard disk drive 1, the cover 4 and the support shaft 20 of the rotary actuator 7 are provided.
Is smaller than the distance L4 between the cover body 4 and the rotary portion 16 of the rotary actuator 7.

Therefore, even if the cover 4 is bent by some external force (load) when the hard disk drive 1 is driven, the cover 4 contacts the support shaft 20 which is a fixed member fixed to the housing 3. The rotating part 16 which is a member on the rotating side
Does not contact with As a result, the operation of the rotary actuator 7 is not hindered and the disk-shaped recording medium 6
Recording or reproducing operation of an appropriate information signal with respect to.

Further, the distance L3 between the cover 4 and the support shaft 20 is defined as the distance L3 between the cover 4 and the uppermost surface of the rotating portion 16.
In order to make it smaller than 4, it is only necessary to protrude the support shaft 20 upward from the rotating part 16, and it is possible to extremely easily realize the operation of recording or reproducing an appropriate information signal on the disk-shaped recording medium 6. .

In addition, in the hard disk drive 1, the motor shaft 10 (10A) of the spindle motor 5 (5A)
A) and the support shaft 20 of the rotary actuator 7 is
, The motor shaft 10 (10A) and the support shaft 2
The hard disk drive 1 can be made thinner because a dedicated chassis for mounting each of the components 0 is not required and no chassis is required.

Further, since a dedicated chassis for mounting each component is not required, the hard disk drive 1
The number of parts can be reduced.

In the above description, an interval is formed between the cover 4 and the motor shaft 10 or the motor shaft 10A, and this interval is made smaller than the interval between the cover 4 and the rotor member 12 or the rotor member 12A. Does not form any gap between the cover body 4 and the motor shaft 10 or the motor shaft 10A. Member 1
You may make it not contact with 2A.

Even when the cover 4 is brought into contact only with the motor shaft 10 or the motor shaft 10A, even if the cover 4 is brought into contact with the motor shaft 10 or the motor shaft 10A.
Between the cover member 4 and the rotor member 12 or the rotor member 12A.
Can be further reduced in thickness.

In the above description, the cover 4 and the motor shaft 1
0 (10A) or the distance between the support shaft 20 and the cover member 4 and the rotor member 12 (12A) or the rotating portion 16 to reduce the distance between the motor shaft 10 (10A) and the support shaft 20.
Is made to protrude upward from the rotor member 12 (12A) or the rotating portion 16, but as shown in FIG. 6, the motor shaft 10 (10A) or the support shaft 20 is not protruded upward. Alternatively, a protrusion 27 protruding downward may be formed on the cover 4 so that the protrusion 27 contacts the motor shaft 10 (10A) or the support shaft 20 when the cover 4 is bent.

It should be noted that the specific shapes and structures of the respective parts shown in the above-described embodiments are merely examples of the specific embodiments performed in carrying out the present invention, and the present invention is not limited thereto. The technical scope should not be construed as limiting.

[0068]

As is apparent from the above description, the hard disk drive of the present invention comprises a disk-shaped recording medium, a spindle motor for rotating the disk-shaped recording medium, and the recording or recording of information signals on the disk-shaped recording medium. A head for performing reproduction, an actuator to which the head is attached and moved to move the head to an arbitrary position on a recording track of a disk-shaped recording medium, and is formed by a housing and a cover body covering the housing. A spindle motor, a disk-shaped recording medium, and an actuator are arranged in an outer casing, and the spindle motor has a non-rotating part whose axial direction is orthogonal to the surface direction of the cover body and is fixed in the outer casing; A hard disk drive having a rotatable portion rotatably supported on the cover, wherein the gap between the cover body and the non-rotatable portion is covered. Characterized by being smaller than the distance between the over body and the rotating portion.

Therefore, even if the cover is bent by applying some external force (load) when the hard disk drive is driven, the cover comes into contact with the non-rotating portion fixed to the housing and does not contact with the rotating portion. It is possible to ensure the proper recording or reproducing operation of the information signal on the disk-shaped recording medium without causing the rotation variation of the motor or the deterioration of the function of the actuator due to the rotation variation.

According to the second aspect of the present invention, since the end of the non-rotating portion located on the cover body side protrudes toward the cover body from the rotating portion, the cover and the non-rotating portion can be very easily connected. The interval can be made smaller than the interval between the cover body and the rotating portion, and it is possible to extremely easily realize the operation of recording or reproducing an appropriate information signal on the disk-shaped recording medium.

According to the third and fourth aspects of the present invention, since the end of the non-rotating portion located on the housing side is fixed to the housing, a dedicated chassis for mounting the non-rotating portion is required. However, since the chassis need not be provided, the thickness of the hard disk device can be reduced, and the number of components of the hard disk device can be reduced.

Another hard disk device of the present invention is:
A disk-shaped recording medium, a spindle motor for rotating the disk-shaped recording medium, a head for recording or reproducing information signals on the disk-shaped recording medium, and a head mounted with the head and rotated to rotate the disk-shaped recording medium An actuator positioned at an arbitrary position of the recording track of the recording track, a spindle motor, a disk-shaped recording medium and an actuator are arranged in an outer casing formed by a casing and a cover body covering the casing, and the actuator is A hard disk drive having a non-rotating part whose axis direction is orthogonal to the surface direction of the cover body and fixed in the outer casing and a turning part rotatably supported by the non-rotating part, The distance between the cover body and the non-rotating part is smaller than the distance between the cover body and the rotating part.

Accordingly, even when the cover is bent by applying some external force (load) when the hard disk drive is driven, the cover comes into contact with the non-rotating portion fixed to the housing and does not contact with the rotating portion. In addition, it is possible to ensure a proper operation of recording or reproducing the information signal on the disk-shaped recording medium without deteriorating the function of the actuator.

According to the invention described in claim 6, since the end of the non-rotating portion located on the cover body side protrudes toward the cover body from the rotating portion, it is very easy to form the non-rotating portion on the non-rotating portion. The distance between the unit and the cover unit can be made smaller than the distance between the cover unit and the rotating unit, so that it is possible to extremely easily realize a proper operation of recording or reproducing an information signal on the disk-shaped recording medium.

According to the seventh and eighth aspects of the present invention, since the end of the non-rotating portion located on the housing side is fixed to the housing, a dedicated chassis for attaching the non-rotating portion is provided. And the need to provide a chassis can reduce the thickness of the hard disk drive and reduce the number of components of the hard disk drive.

[Brief description of the drawings]

FIG. 1 shows a hard disk drive of the present invention together with FIGS. 2 to 6, and is a perspective view showing a state in which a cover is removed.

FIG. 2 is an exploded perspective view.

FIG. 3 is an enlarged vertical sectional view showing a spindle motor.

FIG. 4 is an enlarged vertical sectional view showing a rotary actuator.

FIG. 5 is an enlarged vertical sectional view showing another spindle motor.

FIG. 6 is an enlarged vertical sectional view showing a part of the hard disk drive in which a protrusion is formed on a cover body.

FIG. 7 shows a conventional hard disk drive together with FIGS. 8 and 9, which is an exploded perspective view.

FIG. 8 is an enlarged plan view showing a state where a top cover is removed.

FIG. 9 is an enlarged vertical sectional view showing a spindle motor.

FIG. 10 is an enlarged vertical sectional view showing another spindle motor used in a conventional hard disk drive.

FIG. 11 is a conceptual diagram showing a conventional problem.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Hard disk device, 2 ... outer housing, 3 ... housing, 4 ... cover body, 5 ... spindle motor, 6 ... disk-shaped recording medium, 7 ... rotary actuator (actuator), 1
0: motor shaft (non-rotating portion), 12: rotor member (rotating portion), 16: rotating portion, 20: support shaft (non-rotating portion), 21
... Head, 5A ... Spindle motor, 10A ... Motor shaft (non-rotating part), 12A ... Rotor member (rotating part)

Claims (8)

[Claims] 1. A disk-shaped recording medium, a spindle motor for rotating the disk-shaped recording medium, a head for recording or reproducing an information signal on and from the disk-shaped recording medium, and a head mounted and moved to move the head. An actuator positioned at an arbitrary position on a recording track of the disc-shaped recording medium, wherein the spindle motor, the disc-shaped recording medium and the actuator are arranged in an outer casing formed by a casing and a cover body covering the casing. The spindle motor is a hard disk drive having a non-rotating portion whose axial direction is orthogonal to the surface direction of the cover body and fixed in an outer casing, and a rotating portion rotatably supported by the non-rotating portion. A hard disk drive characterized in that the distance between the cover and the non-rotating part is smaller than the distance between the cover and the rotating part. . 2. The hard disk drive according to claim 1, wherein an end of the non-rotating portion located on the side of the cover protrudes from the rotating portion toward the cover. 3. The hard disk drive according to claim 1, wherein an end of the non-rotating portion located on the housing side is fixed to the housing. 4. The hard disk drive according to claim 2, wherein an end of the non-rotating portion located on the housing side is fixed to the housing. 5. A disk-shaped recording medium, a spindle motor for rotating the disk-shaped recording medium, a head for recording or reproducing an information signal on or from the disk-shaped recording medium, and a head mounted and rotated while the head is mounted. An actuator for positioning the disc at an arbitrary position on a recording track of the disc-shaped recording medium, and the spindle motor, the disc-shaped recording medium and the actuator are disposed in an outer casing formed by a casing and a cover body covering the casing. The hard disk is arranged, and the actuator has a non-rotating part whose axis direction is orthogonal to the surface direction of the cover body and is fixed in the outer casing, and a turning part rotatably supported by the non-rotating part. A hard disk drive, wherein the distance between the cover body and the non-rotating part is smaller than the distance between the cover body and the rotating part. 6. The hard disk drive according to claim 5, wherein an end of the non-rotating portion located on the cover body side protrudes toward the cover body from the rotating portion. 7. The hard disk drive according to claim 5, wherein an end of the non-rotating portion located on the housing side is fixed to the housing. 8. The hard disk drive according to claim 6, wherein an end of the non-rotating portion located on the housing side is fixed to the housing.