JPH06333329A - Magnetic disk driving device - Google Patents

Abstract

PURPOSE:To improve the rigidity of a motor and to prevent air leakage without flawing a frame of the magnetic disk driving device even when plastic working is performed on the frame to form a recessed part by forming the frame out of a Cu added stainless steel material. CONSTITUTION:A hub 7 is mounted with a magnetic disk on its outer circumferential surface, and is rotated together with a driving magnet 8. A stator core 3 opposite to the magnet 8 is fixed by the frame 1 and is wound with a coil 4. A part for sticking a flexible substrate 10 on the lower end surface of the frame 1 has a recessed surface 1d, and the recessed surface 1d is formed in its plasticity by pressing or forging. This frame 1 is formed out of Cu added stainless steel material. Thus, by forming the frame using the Cu added stainless steel material, its spreading property is promoted without flawing the frame even subjected to plastic working by pressing or forging so as to form the recessed part, and the rigidity of the motor is improved and air leakage is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk drive device.

[0002]

2. Description of the Related Art Conventionally, a so-called center axis rotation type magnetic disk drive device is known. The overall structure of this magnetic disk drive device is the same as that shown in FIGS. 1 and 2 showing the embodiment of the present invention, and therefore the following description will be given with reference to FIGS. In FIG. 1, reference numeral 1 indicates a frame made of stainless steel such as SUS303 or the like, and a hollow cylindrical bearing holder portion 1b is erected integrally in the central portion. A stator core 3 is fixed to the outer periphery of the bearing holder portion 1b, and a coil 4 is wound around the core 3. Outer rings of the bearings 5 and 5 are fitted and fixed to the inner circumference of the bearing holder portion 1b, and a center shaft 6 is fitted and fixed to the inner rings of the bearings 5 and 5. A hub 7 shaped so as to cover the core 3, the coil 4, etc. is fitted and fixed to an end portion of the central shaft 6, and a magnetic disk (not shown) is provided on the outer peripheral surface of the core 3 on the inner peripheral surface. The ring-shaped drive magnets 8 are mounted at the positions facing each other. Insulating paper 1 is placed on the upper surface in the figure below the coil 4 of the frame 1.
1, a flexible substrate (Flexible Print Circuit) 1 extends to the outside of the motor on the lower surface.
0 is attached to each. This flexible substrate 1
No. 0 is a conductor pattern formed on a base made of an insulating material, and a cover made of an insulating material is coated on the conductive pattern. As shown in FIGS. 1 and 2, a through hole 1a for drawing out a lead wire (terminal wire) 9 from the coil 4 is formed in the lower portion of the coil 4 of the frame 1, and the lead wire is formed. Reference numeral 9 denotes a through hole (not shown) formed in the insulating paper 11, a through hole 1a of the frame 1, a flexible substrate 10
Through the notch 10a, soldering 10b is performed on the conductor pattern portion (solder land portion) exposed from the cover of the flexible substrate 10. Then, the flexible substrate 1 is supplied from a power supply means (not shown) outside the motor.
By applying a predetermined drive voltage to the coil 4 via the conductor pattern 0 and the lead wire 9, the hub 7 having the magnetic disk mounted thereon is rotated.

[0003]

However, the above magnetic disk drive device has the following problems. That is, the lower surface of the frame 1 where the flexible substrate 10 is attached is a concave surface 1d, and the concave surface 1d is
For example, it is formed by plastic working such as pressing or forging, but the material has a low elongation due to the stainless steel such as SUS303 as described above (the ductility is low). There is a problem that cracks occur, the rigidity of the motor is lowered, and air leaks at the cracked portions. As described above, when the rigidity of the motor decreases, the vibration resistance of the magnetic disk device deteriorates. Therefore, if a read / write error occurs even at a low frequency, and if air leaks, dust and the like outside the motor will be generated. Since it invades inside, there is a fear that a head crash or the like is induced by the dust, which is a problem.

Therefore, according to the present invention, even if plastic working is performed to form a concave portion and a convex portion, the frame does not crack, the rigidity of the motor is improved, and air leakage is prevented. The purpose is to provide.

[0005]

In order to achieve the above object, a magnetic disk drive apparatus of the present invention has a hub for mounting and driving a magnetic disk on the outer peripheral surface thereof, a drive magnet rotating with the hub, and a drive magnet for driving the hub. A magnetic disk drive device comprising: a stator core around which a coil is wound to face a magnet; and a frame for fixing the stator core, wherein the planar portion of the frame has a concave portion or a convex portion. It is characterized in that the frame is formed of a stainless material to which Cu is added.

[0006]

According to the magnetic disk drive device having such means, the malleability of the frame made of a stainless steel material to which Cu is added becomes extremely high, and the plastic working such as pressing or forging is performed to form the concave portion and the convex portion. When applied, it does not cause cracks.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of a magnetic disk drive device showing an embodiment of the present invention, and FIG. 2 is a view of FIG. 1 seen from the bottom. Since the other parts than the frame are exactly the same as the prior art. The description here is omitted. The frame of the magnetic disk drive of this embodiment is different from that of the prior art in that the frame 1 is made of a Cu-added stainless material.

In this embodiment, SUS303Cu having the chemical composition shown in Table 1 is used as the stainless steel material containing Cu. This SUS
As is clear from the table, 303Cu is SUS303 with a Cu component added at 2% to 5%.

[Table 1]

The material made of SUS303Cu is subjected to plastic working such as cold forging to form an intermediate body. Of course, the concave surface 1d is also formed at this point, and the intermediate body thus formed is If only necessary portions are processed by finish cutting, the completed frame 1 shown in FIGS. 1 and 2 can be obtained.

As described above, in this embodiment, since the frame 1 is formed by using SUS303Cu as the stainless material to which Cu is added, the malleability of the frame 1 is remarkably higher than that of the conventional one. Even if plastic working such as pressing or forging is performed to form the concave portion and the convex portion, for example, the step portion 12 is not cracked, so that the rigidity of the motor can be improved and the air leakage can be prevented. Has become. Therefore, it is possible to prevent the read / write error at a low frequency due to the decrease in the rigidity of the motor and the occurrence of the head crash due to the dust due to the air leak.

Although the invention made by the present inventor has been specifically described based on the embodiments, the invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention. Needless to say, for example, SUS303Cu is optimally used as the stainless steel material to which Cu is added in the above embodiment, but the material is not limited to SUS303Cu.

Further, the bearing holder portion 1b and the frame 1
It is also applicable to a type in which and are separate bodies.

Furthermore, it is of course applicable to a fixed center axis type magnetic disk drive.

[0014]

As described above, according to the magnetic disk drive apparatus of the present invention, the frame is made of the stainless material to which Cu is added, so that the extensibility of the frame is very high, and therefore, Even if plastic working such as pressing or forging is performed to form the concave portion and the convex portion, cracking does not occur, and it is possible to improve the rigidity of the motor and prevent air leakage.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a magnetic disk drive device showing an embodiment of the present invention.

FIG. 2 is a view of FIG. 1 seen from below.

[Explanation of symbols]

 1 frame 1d recessed part 3 stator core 4 coil 7 hub 8 drive magnet

Claims (1)

[Claims] 1. A hub for mounting and driving a magnetic disk on an outer peripheral surface thereof, and a drive magnet rotating together with the hub,
A stator core wound with a coil facing the drive magnet, a frame for fixing the stator core,
A magnetic disk drive device having a concave portion or a convex portion in a part of a plane portion of the frame, wherein the frame is formed of a Cu-added stainless material.