JPH06119726A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To improve reliability of a magnetic disk device by obviating a start-up defect of the magnetic disk device and also to shorten the rise time of the device. CONSTITUTION:A damper 112 provided with a difference of level on the outer periphery of the damper 112 is integrally molded with a stud 113. The damper 112 is made rotatable through the stud 113. Two kinds of radii, R-OUT and R-IN are provided for the damper 112. When a servo pattern is written on the magnetic disk 102, the molded part 122 is abutted on the damper 112 with the radius R-OUT. After the servo pattern is written in, the stud 113 is rotated about 90 deg. by using a slitting part 121 of the stud 113. The molded part 122 is abutted on the damper 112 with the radius R-IN at the time of using as the magnetic disk device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk device used as a storage device such as a computer.

[0002]

2. Description of the Related Art Conventionally, a damper for alleviating the shock received by a magnetic head at the time of retracting the arm for moving the magnetic head to a landing area in order to protect data on a magnetic disk, or at the time of arm runaway is shown in FIG. The structure was known. Both the upper yoke 106 and the lower yoke 107 are fixed to the stud 113 by crimping or press-fitting, and the damper 112 is fixed to the stud 113 by press-fitting or the like. The upper yoke 106 and the lower yoke 107 are
In each case, the magnet 108 is fixedly adhered, and a coil (not shown) is supported and fixed to the mold part 122. Further, the magnetic circuit assembly including the upper yoke 106, the lower yoke 107, the stud 113, and the magnet 108 is fixed to the base 110 with the fixing screw 114. When the arm is retracted or the arm is out of control, a current flows through the coil in the mold part 122, so that the mold part 122 contacts the damper 112 with acceleration, and after the mold part 122 contacts, the damping effect of the damper 112 is achieved. Therefore, the acceleration of the mold part 122 is reduced. Further, when the mold part 122 is fixed in order to position and hold the magnetic head in the landing area when not operating, the mold part 122 is fixed by an arm lock mechanism (not shown) in a state of being in contact with the damper 112. It had been.

[0003]

However, the prior art has the following problems.

1) When an offset occurs at the contact point between the mold portion and the damper due to a change with time of the damper, etc., the magnetic head floats out of a predetermined landing area after the power supply of the magnetic disk device is turned on, so that the magnetic head is positioned. There has been a problem that the magnetic head cannot detect the servo pattern written on the magnetic disk for control or speed control, and the magnetic disk device does not start up.

2) In order to avoid the above problem 1), the mold part must be strongly pressed against the damper when writing the servo pattern on the magnetic disk, so that unnecessary stress is applied to the arm and Plastic deformation of the magnetic disk, which significantly deteriorates the reliability of the magnetic disk device.

3) Further, since the servo pattern is written under unnecessary stress, the positioning accuracy of the servo track writer that writes the servo pattern on the magnetic disk by the magnetic head of the magnetic disk device itself is lowered. , And the writing time of the servo track writer was increased, and the cost of the magnetic disk device could not be reduced.

4) Further, when the magnetic head is out of a predetermined landing area and the servo pattern cannot be detected and the magnetic disk device does not start up, a soft start is performed by using a startup sequence for searching the servo pattern. However, there is also a problem that the rise time of the magnetic disk device cannot be shortened due to this soft sequence.

Therefore, the present invention solves the above-mentioned conventional problems, and its purpose is to provide a step on the outer circumference of the damper and fix it to the stud so that the damper can be rotated through the stud. Only by taking measures, the startup failure of the magnetic disk device due to the change of the damper with time is completely eliminated, the arm deformation during servo pattern writing is eliminated, the reliability of the magnetic disk device is improved, and the startup time of the magnetic disk device is shortened. It is an object of the present invention to provide a low-cost magnetic disk drive that can be performed in a short time.

[0009]

A magnetic disk apparatus of the present invention supports at least one magnetic disk, at least one magnetic head corresponding to the magnetic disk, a spindle motor for rotating the magnetic disk, and a magnetic head. A flexure to be fixed, an arm to support and fix the flexure, a coil to drive the arm, a mold part to fix the coil to the arm, a first yoke and a second
At least one adhesively fixed to the first yoke and the first yoke
Magnets, at least one stud forming a gap between the first yoke and the second yoke, at least one damper fixed to the stud, and at least one fixing stud to the base. A magnetic disk device having a book fixing screw, a cover engaging with a base, and an arm lock mechanism capable of holding a mold part in contact with a damper, wherein the stud has a substantially columnar shape, and two crease parts are provided. The straight line that connects the two slivers passes through the approximate center point of the stud, the damper has a substantially cylindrical shape, and has two different diameters on the outer circumference of the damper. It has four parts.

[0010]

In the magnetic disk device of the present invention, the damper is rotatably fixed to the stud and a step is provided on the outer periphery of the damper as described above, so that the servo pattern written in the magnetic disk device is assembled for a long period of time. Thus, it is possible to realize a highly reliable magnetic disk device in which a magnetic head can read out, and a magnetic disk device that can be started up at a low cost in a short time.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. In all the drawings in this embodiment, the same parts are allotted with the same reference numerals.

FIG. 1 is a main plan view showing an embodiment of a magnetic disk device of the present invention. The magnetic disk 102 is rotatably supported and fixed to a spindle motor 109 via a clamper 111, the magnetic head 101 is supported and fixed to a flexure 103 via a gimbal (not shown), and further, the flexure 103 is It is supported and fixed to the tip of the arm 104. The magnetic head 101 of the present embodiment has a negative pressure floating slider shape (not shown). A coil 105 for driving the arm 104 is provided at the other end of the arm 104 in the mold portion 12.
2 is supported and fixed to the arm 104, and the arm 10
4 is swingable around the pivot shaft 123 as the center of the rotation shaft. The magnetic circuit for driving the coil 105 includes an upper yoke 106 and a magnet 10 bonded and fixed to the upper yoke 106.
8 and lower yoke 107 and two studs 113,
The stud 113 and the lower yoke 107 are fixed to the base 110 with a fixing screw 114. Furthermore, the arm 104
The damper 112, which absorbs the shock received by the magnetic head 101 during a runaway or retract, is fixed to the stud 113 by integral molding, press fitting, or adhesion. Circulation filter 11 to keep the environment sealed by base 110 and cover (not shown) always clean.
9 is fixed to the base 110.

When not in operation, the mold part 122 has the damper 1
12 and the arm 104 is fixed by the arm lock mechanism 120 via the mold part 122. At the same time, the flexure 103 is attached to the flexure lock mechanism 117 to prevent contact between the magnetic head 101 and the magnetic disk 102. It is fixedly held.

After the power is turned on, the spindle motor 109 starts to rotate and the magnetic disk 102 rotates to release the flexure lock mechanism 117. Next, a voltage is applied to the loading mechanism 116, and the flexure 10
The magnetic head 101 is floated on the magnetic disk 102 by pressing the specific points of 3. The servo pattern which should have been previously written on the magnetic disk 102 is on the RH of FIG. 1 or the output of the magnetic head 101 is passed through a flexible printed circuit (hereinafter referred to as FPC) 118 to a main board (not shown). Not send) to. When a desired output is obtained from the magnetic head 101, a voltage is applied to the arm lock mechanism 120, the mold part 122 is released, the arm 104 can be positioned on a desired track, and the magnetic disk device can be used. If the desired output cannot be obtained from the magnetic head 101, the magnetic disk device cannot be used.

Therefore, it is understood that the servo pattern must exist at the position where the magnetic head 101 is levitated in order to keep the magnetic disk device usable by the user. Therefore, a method for mechanically simply improving the reliability of the magnetic disk device will be described with reference to FIG. 2 as well as FIG.

FIG. 2 is a detailed main plan view showing an embodiment of the magnetic disk device of the present invention, and is an enlarged view of the main part of FIG. The damper 112 is a mold part 12 used when writing a servo pattern on the magnetic disk 102.
2 of the contact radius R-OUT with 2 and R-IN used as a magnetic disk device after the servo pattern writing is completed.
It has four kinds of radii and owns four steps. When the mold portion 122 is in contact with the R-OUT of the damper 112, the magnetic head 101 can swing up to RS in FIG. 1, and writes a servo pattern up to the RS area.
Next, after writing the servo pattern, the stud 113 is rotated about 90 degrees using the threaded portion 121 of the stud 113. That is, as shown in FIG. 2, since the mold portion 122 contacts the damper 112 in the R-IN state, the magnetic head 101 can swing only up to RH in FIG. Therefore, the damper 11 due to changes over time
Even if the second creep or the like occurs, the magnetic head 101
Is always levitated on the inner peripheral side of the RH on the magnetic disk 102, the servo pattern can be detected at the time of startup, and the magnetic disk device of the present invention has no startup failure, and the reliability is dramatically improved. It is clear that it will improve.

Next, FIG. 3 is used to explain the method of fixing the stud 113. FIG. 3 is a detailed main sectional view showing an embodiment of the magnetic disk device of the present invention. In order to effectively explain the sectional view, the mold portion 122 and the damper 11 are shown.
2 is not in contact. Stud 113 and upper yoke 10
6, the stud 113 and the lower yoke 107 are the upper yoke 1
It is fixed by the magnetic force of the magnet 108 adhered and fixed to 06, and the damper 1 is attached to each of the upper yoke 106 and the lower yoke 107 so that the stud 113 can be easily rotated.
The structure is such that 12 does not contact, and the stud 113 can be easily rotated by a slotted screwdriver or the like using the threaded portion 121 provided above the stud 113. The base 110 has a counterbore, and the stud 113
The lower part of the is fitted into the counterbore part of the base 110, and the upper yoke 106, the lower yoke 107, the magnet 108, and the stud 113.
A magnetic circuit including the above is temporarily fixed to the base 110. In addition, the base 110 is also provided with a tap, and the stud 1
The stud 1 is fixed with a fixing screw 114 penetrating the center of
The magnetic circuit is fixed to the base 110 via 13. When writing a servo pattern, the stud 113 is temporarily fixed to the base 110 with the fixing screw 114 (the magnetic head 101 is in a swingable state up to the range of RS shown in FIG. 1). Sleeve part 121
In addition, the head of the fixing screw 114 does not project, and the stud 113 can be easily rotated. When the writing of the servo pattern is completed, the stud 113
Is rotated about 90 degrees (the magnetic head 101 can swing to the RH range shown in FIG. 1), and the magnetic circuit is firmly fixed to the base 110 via the stud 113. When fixing the stud 113 to the base 110 with the fixing screw 114, the washer 115 is provided to prevent the deviation of the stud 113 in the rotation direction.
It is equipped between 3 and.

Generally, the damper 112 is often made of synthetic rubber, urethane, or the like, and is difficult to machine, and even if it is possible, the damper 11 is used.
The problem of dust generation from the machined surface of 2 remains. In this embodiment, the damper 112, which is a synthetic rubber, is attached to the stud 1.
13 is integrally molded, the precision of the parts of the damper 112 is measured, and the step on the outer circumference of the damper 112 is obtained. Accuracy of parts of damper 112 diameter is plus / minus 0.1mm
And the coaxiality of the outer circumference of the damper 112 is 0.1 mm.
Therefore, in order to use the outer circumference of the damper 112 in the magnetic disk device without machining, the step difference of the outer circumference must be at least 0.15 mm or more. When converted to diameter, the difference between the two diameters is 0.3 mm or more. By the way, the precision of the diameter of the stud 113 for machining is within ± 0.05mm.
The coaxiality of the outer circumference of 13 is within 0.01 mm. further,
Considering the hole accuracy of the counterbore portion of the base 110 and the like, it is more preferable that the step on the outer periphery is 0.2 mm or more. That is, FIG.
Two types of radii R-IN and R-OU of the damper 112 inside
The difference from T is preferably 0.2 mm or more. In this embodiment, 8.2 mm is used for R-IN and 8 mm is used for R-OUT.

In order to avoid the distortion of the base 110 that occurs when the cover is fixed to the base 110, the writing of the servo pattern is performed on a substantially completed magnetic disk device. The cover of the magnetic disk device of the present invention has an opening provided directly above the stud 113 in FIG. 1 so that the servo pattern can be written in a substantially completed product. In this embodiment, the diameter of the threaded portion 121 of the stud 113 is 8 mm,
The diameter of the opening of the base 110 is set to 10 mm, and the stud 113 is easily rotatable with a commercially available flat-blade screwdriver after the magnetic disk device is assembled substantially.

As described above with reference to FIGS. 1 to 3, a step is provided on the outer periphery of the damper 112 to provide the stud 113.
By making the structure rotatable in the assembly process of the magnetic disk device, not only the reliability of the magnetic disk device is dramatically improved, but also the servo of the magnetic disk device is improved.
It goes without saying that the startup sequence for searching for a pattern can be omitted and the startup time becomes faster. Further, as can be seen from the comparison between FIG. 8 of the conventional example and FIG. 3 of the present invention, the number of components increased by the present invention is the washer 11
5, the washer 115 can be removed in some cases, and the cost of parts hardly increases. Further, since it is not necessary to press the damper 112 against the mold portion 122 to write the servo pattern,
It goes without saying that the servo pattern writing time can be shortened and the non-defective product rate can be improved by eliminating the deformation of the arm 104, and that the present invention greatly contributes to the cost reduction of the magnetic disk device.

In this embodiment, the slider shape of the magnetic head 101 is a negative pressure floating type, and the magnetic disk 102 is
Although the magnetic disk device for loading the magnetic head 101 on the outer peripheral side of the magnetic head has been taken up, the slider shape of the magnetic head is a positive pressure floating system, and the magnetic disk device in which the magnetic head floats on the inner peripheral side of the magnetic disk is used. Even if the invention is applied, the effects of the present invention are not lost.

Further, in this embodiment, since the magnetic head floats only on the outer peripheral side or the inner peripheral side on the magnetic disk, only one stud which is the structure of the magnetic disk device of the present invention is used. By using two studs in the magnetic circuit, it is possible to further improve the reliability of the magnetic disk device even when the magnetic head runs away on the inner and outer circumferences.

FIG. 4 is a main plan view showing an embodiment of a stud and a damper which are the structures of the magnetic disk device of the present invention. The stud 113 has a threaded portion 121 on the upper portion thereof, and the damper 112 has an outer periphery. Is eccentric with respect to the center point of the outer circumference of the stud 113. This can be performed by using the thin portion of the damper 112 when writing the servo pattern and using the thick portion of the damper 112 after writing the servo pattern. Further, in the embodiment shown in FIG. 4, the damper 112 is used.
Was eccentrically fixed to the stud 113, but the damper 1
It goes without saying that the same effect can be obtained even if the shape of 12 is elliptical.

FIG. 5 is a main plan view showing another embodiment of the stud and the damper which are the structures of the magnetic disk device of the present invention.
The damper 112 has two kinds of diameters and two step portions on the outer circumference. This can be performed by using the thin outer peripheral portion of the damper 112 when writing the servo pattern, and using the thick outer peripheral portion of the damper 112 after writing the servo pattern.

FIG. 6 is a main plan view showing another embodiment of the stud and the damper which are the structures of the magnetic disk device of the present invention.
The damper 112 has two kinds of diameters on the outer periphery and four step portions at every 90 degrees. A straight line connecting the two threaded portions 121 passes through the center point of the stud 113 and the center of each step portion. As can be seen from FIG. 3, in the configuration of the magnetic disk device of the present invention, the upper yoke 10
Since 6 almost covers the damper 112, it is very effective in the assembling process to use the threaded portion 121 above the stud 113 as a guide for positioning.

FIG. 7 is a main plan view showing another embodiment of the stud and the damper which are the structures of the magnetic disk device of the present invention.
The damper 112 has two kinds of diameters and four stepped portions on the outer circumference. Two sledding parts 12
The straight line connecting 1 is an angle of X degree with respect to the center line passing through the center point of the stud 113, and the straight line connecting the middle points of the step portions on the outer circumference of the damper 113. In FIG. 2 of this embodiment,
The angle of X is about 11 degrees. By making this angle of 11 degrees, the contact point of the mold part 122 becomes R
It becomes the midpoint of the two steps forming -IN, and when the mold part 112 has an acceleration and collides with the contact point, the acceleration of the mold part 122 can be reduced under optimum conditions. Furthermore, when writing a servo pattern, the stud 113
The straight line that connects the two sledding parts 121 is the base 110
Is perpendicular to the side wall of the base 110, and after the servo pattern writing is completed, the straight line connecting the two threaded portions 121 of the stud 113 becomes parallel to the side wall of the base 110. In addition, since the outer periphery of the damper 112 has a line-symmetrical shape, even if the stud 113 is rotated 180 degrees, the positional relationship in which the mold part 122 and the damper 112 contact each other does not change, and the magnetic disk device is assembled or assembled. The robot can be easily managed.

Further, in this embodiment, after the writing of the servo pattern is completed, the slipping portions 12 of the stud 113 at the two positions are formed.
Although the straight line connecting 1 is parallel to the side wall of the base 110, the effect of the present invention is not lost even if the shape of the damper 112 is changed so that the straight line connecting the threaded portion 121 is perpendicular to the side wall of the base 110. Absent.

Finally, in this embodiment, 11 degrees was used for X, but this angle is the same as the pivot shaft 123 and the stud 11 in FIG.
3 and the shape of the damper 112 or the shape of the mold part 122. Therefore, the angle of X is 0
It is possible to select from 90 degrees to 90 degrees, and the effect of the present invention is not lost no matter which angle X is used.

[0029]

As described above, according to the present invention, by providing a magnetic disk device having a structure in which a step is provided in the damper part and the stud can be rotated, 1) a mold part is formed due to a change with time of the damper and the like. Even if an offset occurs at the contact point of the damper, the magnetic head can always detect the servo pattern written on the magnetic disk for positioning control or speed control of the magnetic head after the magnetic disk device is powered on. It is possible to eliminate the problem that the magnetic disk device does not start up.

2) When the servo pattern is written on the magnetic disk, it is not necessary to press the mold part strongly against the damper or to apply unnecessary stress to the arm, so that the arm may be plastically deformed. Therefore, the reliability of the magnetic disk device can be remarkably improved.

3) Further, since the servo pattern is not written under the condition that unnecessary stress is applied,
The positioning accuracy of the servo track writer that writes the servo pattern on the magnetic disk with the magnetic head of the magnetic disk device itself does not decrease, the servo pattern can be written in a short time, and the cost of the magnetic disk device can be reduced. Become.

4) Further, since the magnetic head never goes out of a predetermined landing area and the servo pattern cannot be detected by the magnetic head, the start-up sequence for searching for the servo pattern is unnecessary, and the magnetic disk device starts up. The time can be greatly reduced.

As described above, the practical effect of the present invention is extremely large.

[Brief description of drawings]

FIG. 1 is a main plan view showing a magnetic disk device according to an embodiment of the present invention.

FIG. 2 is a detailed main plan view showing a magnetic disk device according to an embodiment of the present invention.

FIG. 3 is a detailed main sectional view showing a magnetic disk device according to an embodiment of the present invention.

FIG. 4 is a main plan view showing a stud and a damper which are structures of a magnetic disk device according to an embodiment of the present invention.

FIG. 5 is a main plan view showing a stud and a damper of a magnetic disk device according to another embodiment of the present invention.

FIG. 6 is a main plan view showing a stud and a damper of a magnetic disk device according to another embodiment of the present invention.

FIG. 7 is a main plan view showing a stud and a damper of a magnetic disk device according to another embodiment of the present invention.

FIG. 8 is a main cross-sectional view showing the internal configuration of a conventional magnetic disk device.

[Explanation of symbols]

 101 magnetic head 102 magnetic disk 103 flexure 104 arm 105 coil 106 upper yoke 107 lower yoke 108 magnet 109 spindle motor 110 base 111 clamper 112 damper 113 stud 114 fixing screw 115 washer 116 loading mechanism 117 flexure lock mechanism 118 FPC 119 circulating filter 120 arm Lock mechanism 121 Threaded part 122 Molded part 123 Pivot shaft

Claims (10)

[Claims] 1. At least one magnetic disk, and at least one magnetic head corresponding to the magnetic disk,
A spindle motor for rotating the magnetic disk,
A flexure for supporting and fixing the magnetic head, an arm for supporting and fixing the flexure, a coil for driving the arm, a mold part for fixing the coil to the arm, a first yoke and a second yoke, At least one magnet adhesively fixed to the first yoke, at least one stud forming a gap between the first yoke and the second yoke, and at least one fixed to the stud. Magnetic disk device having one damper, at least one fixing screw for fixing the stud to the base, a cover engaging with the base, and an arm lock mechanism capable of holding the mold portion in contact with the damper. And the stud has at least one
A magnetic disk drive having a sloping portion at one place. 2. The magnetic disk drive according to claim 1, wherein the damper has at least one step portion on the outer peripheral portion thereof. 3. The stud has a substantially cylindrical shape, the damper has a substantially cylindrical shape, and a substantially center point of the damper is eccentric with respect to a substantially center point of the stud.
The magnetic disk device described. 4. The magnetic disk drive according to claim 1, wherein the damper has a substantially elliptical shape. 5. At least one magnetic disk and at least one magnetic head corresponding to the magnetic disk,
A spindle motor for rotating the magnetic disk,
A flexure for supporting and fixing the magnetic head, an arm for supporting and fixing the flexure, a coil for driving the arm, a mold part for fixing the coil to the arm, a first yoke and a second yoke, At least one magnet adhesively fixed to the first yoke, at least one stud forming a gap between the first yoke and the second yoke, and at least one fixed to the stud. Magnetic disk device having one damper, at least one fixing screw for fixing the stud to the base, a cover engaging with the base, and an arm lock mechanism capable of holding the mold portion in contact with the damper. The stud has a substantially columnar shape and has two slivers, and the straight line connecting the two slivers is the above-mentioned. The damper has a substantially cylindrical shape passing through a substantially central point of the tod, has two different diameters on the outer circumference of the damper, and has four step portions having substantially equal angles on the outer circumference of the damper. Magnetic disk drive. 6. A magnetic disk drive according to claim 5, wherein a straight line connecting the two slip lines has a damper shape which is substantially parallel to the side wall of the base. 7. A magnetic disk drive according to claim 5, wherein a straight line connecting the two slip lines has a damper shape which is substantially perpendicular to the side wall of the base. 8. The magnetic disk drive according to claim 5, wherein the cover has at least one opening at the position of the stud. 9. The magnetic disk drive according to claim 5, wherein the difference between the two different diameters is 0.3 mm or more. 10. A magnetic disk drive according to claim 5, 6, 7, 8 or 9, wherein the stud is rotated by about 90 degrees after writing the servo pattern.