JPH03278365A - Mounting structure for magnetic disk - Google Patents

Abstract

PURPOSE:To generate a tightening force uniformly extending over the entire circumference of a magnetic disk and to accurately perform a recording/ reproducing operation by performing the cutting of a disk sandwiching plane formed on each of a mounting flange and a disk presser body while a spindle motor is rotated. CONSTITUTION:A disk mounting member 3 is rotated on a pedestal 17 with a spindle 23, and the cutting of both the disk sandwiching plane 11a of the mounting flange 11 and the disk sandwiching plane 9a of the disk presser body 9 are performed by using, for example, a cutoff disk presser body 9 are performed by using, for example, a cutoff tool. By performing such cutting, accurate squareness for the central axis of the spindle 23 which becomes the rotary shaft of the magnetic disk 1 when rotating can be obtained, and the magnetic disk 1 can be sandwiched and fixed between the disk sandwiching planes 9a and 11a in which the accurate squareness are obtained for the spindle 23, therefore, the tightening force can be attached uniformly on the entire circumference of the magnetic disk 1. In such a way, it is possible to prevent the camber and bending of the magnetic disk 1 occurring, which enables the recording/reproducing operation to be accurately performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention (Field of Industrial Application) This invention relates to a mounting structure for a magnetic disk in a magnetic disk device.

(Prior Art) In recent years, magnetic disk drives have become increasingly larger in capacity and smaller in size, and magnetic disk drives are now being installed in portable so-called laptop and portable computers.

A main part of a conventional example of such a magnetic disk device is shown in a vertical sectional view in FIG. Pivot boss 103 of base 101
Bearing 105.105 by spindle 107
At the upper end of the spindle 107, there is a motor hub 10 which is a rotor side and has a generally hollow cylindrical shape with an open lower end.
The center of the upper end 111 of 9 is fixed. A permanent magnet 113 is attached to the inner peripheral surface of the motor hub 109, and a stator coil 115 is attached to the pivot boss 103 facing the inner surface of the permanent magnet 113. This stator coil 115, the motor hub 109 and the permanent magnet 11
3, the spindle motor 117
It constitutes the main part of.

A mounting flange 119 and a boss portion 121 are formed on the outer periphery of the motor hub 109, and the magnetic disk 123 is attached to the boss portion 121 using the mounting hole 125 of the magnetic disk 123.
is inserted into. A ring-shaped disk holding body 127 is inserted into the upper end 111 of the motor hub 109, and by pressing the disk holding body 127 toward the mounting flange 119 using the mounting screws 129, the magnetic disk 12 is inserted.
3 is attached to the motor hub 109.

However, in the magnetic disk mounting structure described above, the disk holding body 127 is stacked on the motor hub 109 in the axial direction of the spindle 107, and the motor hub 109
Since it is necessary to secure a gap in the screwing direction between the magnetic disk 123 and the disk holding body 127,
As a result, the stator coil 1 constituting the spindle motor 117 becomes larger.
15 and the permanent magnet 113 must be made smaller, and there is a risk that the margin driving force for rotating the magnetic disk 123 at a predetermined high speed will be reduced, resulting in uneven rotation.

In order to solve this problem, conventionally, as shown in FIG.
In many cases, a structure is adopted in which a disk retainer 9 screwed into a male thread 7 formed on the outer periphery of the upper end 5 of the motor hub 3 is clamped and fixed between a mounting flange 1 formed on the outer periphery of the motor hub 3. In the spindle motor 15 in this case, a spindle 23 is supported by a bearing 21.21 on a support boss 19 of a base 17, the center of the upper end 5 of the motor hub 3 is attached to the upper end of the spindle 23, and a permanent magnet is attached to the center of the upper end 5 of the motor hub 3. 25 is attached to the inner peripheral surface of the motor hub 3, and the stator coil 27 is attached to the outer periphery of the shaft support boss 19.

The mounting hole 1a of the magnetic disk is fitted into the boss portion 29 formed on the upper part of the mounting flange 11, and the disk holding body 9 is inserted.
When screwing the female screw 31 into the male screw 7, the magnetic disk 1 is clamped and fixed by the disk clamping surface 11a of the mounting flange 11 and the disk clamping surface 9a of the disk presser 9.

(Problem to be solved by the invention) However, the conventional magnetic disk mounting structure shown in FIG. It is difficult to ensure a perpendicularity between the female screw 31 and the disk clamping surface 9a, and therefore, when the disk holding body 9 is tightened and the magnetic disk 1 is fixed to the motor hub 3, the perpendicularity of the female screw 31 and the disk clamping surface 9a is evenly spaced around the entire circumference of the magnetic disk 1. Tightening fails to generate force, and as a result, the magnetic disk 1 warps or bends, resulting in abnormal recording and reproducing operations on the magnetic disk 1.

Therefore, the present invention aims to generate a tightening force evenly over the entire circumference of the magnetic disk held between the mounting flange of the disk mounting member and the disk presser by screwing the disk holding body into the disk mounting member. [Structure of the Invention] (Means for Solving the Problems) In order to solve the above problems, the present invention provides a method in which a mounting flange is formed on the outer periphery of a disk mounting member connected to a spindle motor that rotates a magnetic disk. , a magnetic disk in which a mounting hole for the magnetic disk is inserted into the outer periphery of the disk mounting portion, and a female thread of a disk holding body is screwed into a male screw formed on the outer periphery of the disk mounting member, so that the magnetic disk is clamped and fixed between the mounting flange and the disk holding body. Installation 811
In a, at least one of the disk clamping surfaces formed on the mounting flange and the disk holding body is cut while the spindle motor is rotating, and the disk clamping surface that is not cut is It is configured to be able to elastically suppress the magnetic disk. (Operation) When the spindle motor that rotates the magnetic disk is rotated with the disk holding body screwed into the disk mounting member, and the disk holding surface is cut in this state, the disk holding surface is cut. , the disc clamping surface can be properly perpendicular to the rotation axis. When a magnetic disk is clamped and fixed between disk clamping surfaces having a perpendicularity, a tightening force is applied evenly over the entire circumference of the magnetic disk. In addition, if only one disk clamping surface is machined in the same way as above and the other disk clamping surface is not, this other disk clamping surface will elastically press against the magnetic disk. Tightening force is applied evenly over the entire circumference of the magnetic disk.

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

FIG. 1 shows a first embodiment of the present invention, in which each disk holding surface 9a of a disk holding body 9 and a mounting flange 11 is shown.
and lla are shown being cut. In this cutting process, first, without attaching the magnetic disk 1 to the motor hub 3, the disk presser body 9 is screwed into the upper end portion 5 of the disk mounting member 3.
is fixed to the disc mounting member 3. Next, the disk mounting member 3 is rotated together with the spindle 23 relative to the base 17, and both the disk clamping surface 11a of the mounting flange 11 and the disk clamping surface 9a of the disk presser 9 are cut using, for example, a parting tool 37. do.

In order to rotationally drive the disk mounting member 3 during the cutting process, a drive circuit of the spindle motor 15 is used, and a means for rotating the disk mounting member 3 by passing a drive current through the stator coil 27 is not shown. The disk holding member 9 is chucked by a chuck of a lathe, or a means for rotating the disk mounting member 3 from the outside is used, such as using a cutter connected to the disk holding body 9.

Disc clamping surfaces 9a and 11 of the disc presser body 9 and mounting flange 11 cut by the above-mentioned means
Since a is cut while the spindle motor 15 is rotating, the perpendicularity to the center axis of the spindle 23, which is the axis of rotation of the magnetic disk 1, can be accurately obtained.

After cutting, remove the disk holder 9 and remove the magnetic disk 1.
The magnetic disk 1 is attached to the motor hub 3 by fitting it into the motor hub 3 and screwing the disk presser 9 into the motor hub 3 again.

The magnetic disk 1 mounted in this manner is clamped and fixed between the disk clamping surfaces 9a and 1.18, which are precisely perpendicular to the spindle 23.
A tightening force is applied evenly to the entire circumference of the magnetic disk 1, and the occurrence of warping or bending of the magnetic disk 1 is prevented. As a result, recording and reproducing operations on the magnetic disk 1 can be performed accurately.

FIG. 3 shows a second embodiment of the invention. In this embodiment, only the disk holding surface 11a of the mounting flange 11 is cut while being rotated together with the spindle 23 as in the first embodiment, while the disk holding body 3
A ring-shaped ring groove 41 having a semicircular cross section, for example, is provided on the disk clamping surface 39H of 9, and a ring-shaped elastic body 43 made of rubber or the like is fitted into the ring groove 41.

This embodiment is suitable for cases where cutting is difficult in the above-mentioned conditions, or when it is difficult to obtain a perpendicularity of the disk holding surface 39a of the disk holding body 39 to the spindle 23 even with cutting, or when the disk holding surface 39a is difficult to obtain. This has the advantage that it can be applied when cutting is omitted. According to this second embodiment, since the disk clamping surface 11a of the mounting flange 11, which is machined as described above, has an accurate perpendicularity to the spindle 23, the disk holding body 39 can be attached to the motor hub 3. When screwed into the elastic body 4
3 will push the magnetic disk 1 evenly over the entire circumference toward the mounting flange 1]. As a result, the disk clamping surface 11g of the mounting flange 11 and the magnetic disk 1
are in close contact with each other, the warping and bending of the magnetic disk 1 is prevented, and recording and reproducing operations are performed correctly.As a result, both disk clamping surfaces 9a and 1.1a are machined together. The same effect will be obtained.

In the second embodiment, the elastic body 43 is connected to the ring groove 41.
FIG. 4 shows a sectional view of a disk holding body 45 as a third embodiment, which prevents the disk from coming off. In this third embodiment, a ring groove 49 which is narrow at the entrance side and wide at the bottom side and which opens into the disk clamping surface 45a is provided in the disk clamping surface 458, and an elastic body 51 made of a ring-shaped rubber or the like is fitted into the ring groove 49. This is what I did. Elastic body 51
is formed from a fixing part 51a that is fitted into the ring groove 49 and a pressing part 51b that contacts and presses the magnetic disk 1.

Next, as in the second and third embodiments, only the disk clamping surface 11a of the mounting flange 11 is cut when the spindle 23 rotates, and the necessary elastic function is added to the disk clamping surface itself of the disk holding body. Two embodiments will now be described.

First, the fourth embodiment shown in FIG.
The outer shape of the upper side is made smaller in order to form a flange 55 on the lower side in the figure including the disk clamping surface 53a of No. 3.
A ring-shaped convex portion 57 is provided on the disc clamping surface 53a. When the disk presser 53 formed in this manner is screwed into the motor hub 3 and presses the magnetic disk 1, the flange 55 is elastically deformed and the convex portion 57 contacts and presses the magnetic disk 1. As a result, the magnetic disk 1 is pressed evenly over the entire circumference, and the mounting flange 11
The disc gripping surface 11a is evenly and closely attached to the disc clamping surface 11a.

In the fifth embodiment shown in FIG. 6, the flange 61 including the disk holding surface 59a of the disk holding body 59 is inclined so that the outer peripheral side approaches the magnetic disk 1 side.
By elastically deforming this flange 61 when pressed, the disk clamping surface 59a comes into close contact with the magnetic disk 1, and the fifth
The same effect as the fourth embodiment shown in the figure can be obtained.

In addition, in the second to fifth embodiments, while the disk holding surface 11a side of the mounting flange 11 is cut when the spindle 23 rotates, the disk holding bodies 39, 45,
The magnetic disk 1 is pressed against the magnetic disk 1 by giving an elastic function to the 53 and 59 sides, but these are reversed, that is, only the disk holding body 39, 45, 53, and 59 sides are cut when the spindle 23 rotates. and mounting flange 1
The disk holding surface 1.1a side of the disk holding surface 1.1a may have an elastic function, and the same effect as described above can also be obtained by this. In addition, by interposing a spacer between the side that has an elastic function, that is, the elastic body 43.51 and flange 55°61 side and the magnetic disk 1, the magnetic disk 1 can be pressed more evenly over the entire circumference. can generate force.

Next, the disk presser body 9, 39, 45° 53.
59 into the male thread 7 of the motor knob 3 will be described with reference to FIGS. 7 to 14, which have various engaging parts that can be engaged with tools not shown.

What is shown in FIGS. 7 and 8 is a disk holding body 63.
The outer periphery of the disk holding surface 63a and the opposite side thereof are formed into a polygonal shape, and this is used as the engaging portion 65.

What is shown in Fig. 19 and Fig. 10 is the disc presser rest 6.
Four circular engagement recesses 69 are provided at equal intervals in the circumferential direction on the surface opposite to the disk clamping surface 67m of No. 7.

11 and 12, four semicircular engagement recesses 73 are provided at equal intervals in the circumferential direction on the outer circumference of the disk holding body 71 on the side opposite to the disk clamping surface 71a.

In the case shown in FIGS. 13 and 14, three engaging notches 77 are provided at equal intervals in the circumferential direction on the outer periphery of the disk holding body 75 on the side opposite to the disk clamping surface 75a.

[Effects of the Invention] As is clear from the above, according to the present invention, each disc clamping surface of the disc mounting member and the disc holding body that is cut while the spindle motor is rotating is perpendicular to the rotation axis. The angle is accurately obtained, and as a result, the magnetic disk is clamped and fixed between the disk mounting member and the disk holder, and is pressed evenly over the entire circumference, preventing the magnetic disk from warping or bending, and recording. Playback operations can be performed accurately.

In addition, only one of the disk clamping surfaces of the disk mounting member and the disk holding body is cut when the spindle motor rotates, and the other disk clamping surface, which is not cut, is elastically pressed against the magnetic disk. In the configuration, the disk clamping surface on the side that is not cut elastically presses the magnetic disk against the cut disk clamping surface evenly over the entire circumference, thereby preventing warping or bending of the magnetic disk. This prevents the occurrence of such problems, and enables accurate recording and reproducing operations.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing the state in which the disk clamping surface is cut in the first embodiment of the present invention, FIG. 2 is a cross-sectional view showing the state in which the magnetic disk is attached, and FIG. FIGS. 4 to 6 are sectional views showing a second embodiment, and FIG. 7 is a sectional view of a disc presser showing third to fifth embodiments of the present invention. FIG. 9, FIG. 11, and FIG. 13 are plan views of the disk holder showing a shape that engages with a tool for screwing the disk holder into a disk mounting member; FIG. 8 is a plan view of the disk holder. Figures 10, 12, and 14 are the ■− of Figure 7, respectively.
■ Cross-sectional view, XX cross-sectional view in Figure 9, xn-x in Figure 11
The n-section, the XIV-XIV sectional view in FIG. 13, and FIG. 15 are sectional views showing a conventional example. 1...Magnetic disk 1a...Mounting hole 3...Motor hub (disk mounting member) 7...Male thread 9.39, 45.5B, 59.63, 67° 71.75
・・・Disc presser body

Claims (1)

[Claims] A mounting flange is formed on the outer periphery of a disk mounting member connected to a spindle motor that rotates the magnetic disk,
In the magnetic disk, a mounting hole for the magnetic disk is inserted into the outer periphery of the disk mounting part, and a female thread of a disk holding body is screwed into a male thread formed on the outer periphery of the disk mounting member, thereby clamping and fixing the magnetic disk between the mounting flange and the disk holding body. In the mounting structure, at least one of the disk clamping surfaces formed on the mounting flange and the disk holding body is cut while the spindle motor is rotating, and the disk clamping surface that is not cut is , a magnetic disk mounting structure characterized in that the magnetic disk can be elastically pressed.