JP2534442Y2 - Magnetic disk drive - Google Patents

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, and more particularly to a hub structure for holding and rotating a magnetic disk.

[0002]

2. Description of the Related Art FIG. 2 shows a conventional example of a drive device for various magnetic disks, for example, a hard disk. In FIG. 2, the frame 60 has a dish-shaped portion and a shaft 62 integrally formed at the center thereof, and the shaft 62 has a large-diameter lower portion and a small-diameter upper portion. The inner ring 6 of the upper and lower two ball bearings 66 is provided on the outer periphery of the upper part of the shaft 62.
7, 67 are fitted, and the outer rings 68, 68 of the ball bearings 66, 66 are fitted to the inner diameter of the hub 70, so that the hub 70 is rotatably supported. The hub 70 is for holding and rotating a magnetic disk (not shown) integrally, and has a stepped portion 72 for holding the magnetic disk at an outer diameter portion and a disk fixing screw hole 75 at an upper end portion. doing. One or a plurality of magnetic disks are stacked on the stepped portion 72 with an appropriate spacer interposed therebetween, and a clamper is further stacked thereon. The set screw inserted into the clamper is attached to the disk fixing screw. Hole 7
5, the magnetic disk is integrally fixed to the hub 70. The disk fixing screw hole 75 is
The hub 70 is a so-called blind hole which is formed from the upper end side to the middle downward and is closed at the lower end side.

A portion of the hub 70 below the step 72 has a larger diameter and is located inside a dish-like portion of the frame 60, and a ring-like yoke 74 is provided inside the portion below the step 72. The ring-shaped drive magnet 76 is fixed via the. A stator core 78 is fitted and fixed to a large diameter lower part of the shaft 62 of the frame 60.
The stator core 78 has a plurality of salient poles, each salient pole faces the inner peripheral surface of the drive magnet 76, and a coil 80 is wound around each salient pole. The drive magnet 76 and a member integrated therewith constitute a rotor of a disk drive motor, and the stator core 78 and the coil 80 constitute a stator of the motor.

A notch groove 64 is formed at the lower end of the dish-shaped portion of the frame 60, and a hole 63 is formed at the bottom of the dish-shaped portion. A lead wire 82 is connected to a winding end of the coil 80, and the lead wire 82 is inserted into the hole 63 and led out of the motor. The hole 63 is sealed with a sealing material 84, and the lead wire 82 is drawn out along the notch groove 64 and connected to a connector 86. Ball bearings 66, 6 are provided at the upper end of the hub 70.
A magnetic fluid seal mechanism 90 is provided to prevent oil mist, dust and the like from being scattered and attached to the disk. Since the frame 60 is generally integrally formed of aluminum together with the shaft 62, in order for the magnetic fluid sealing mechanism 90 to function effectively, a portion corresponding to the magnetic fluid sealing mechanism 90 at the upper end of the shaft 62 is made of a magnetic material. The ring 69 is fitted and fixed.

[0005]

As described above, in the conventional magnetic disk drive, the disk fixing screw hole 75 formed in the hub 70 is formed halfway from one end of the hub 70 to the other end. Since one end is a so-called blind hole with one end closed, chips, dust and the like generated by processing the hub 70 easily accumulate in the screw hole 75, and it is difficult to remove even if washing is performed. In some cases, chips or dust coming out of the screw holes 75 during use after completion of the magnetic disk drive may adhere to the magnetic disk and break the magnetic disk or the magnetic head. There was a risk of damage.

The present invention has been made in order to solve such a problem of the prior art. Even if chips or debris intrudes into a disk fixing hole formed in a hub, the present invention is applicable.
By adopting a configuration that can easily remove the above-mentioned chips and debris after machining the hub, the chips and debris coming out of the disc fixing holes are drastically reduced. Without destroying
An object of the present invention is to provide a highly reliable magnetic disk drive.

[0007]

In order to achieve the above object, the present invention comprises a motor unit, a magnetic disk fixed, and a hub for rotating the magnetic disk by being driven to rotate by the motor unit. In the magnetic disk drive device described above, the hub was provided with a disk fixing hole penetrating from the end face of the hub to the motor portion, and a seal was attached to the motor-side end face of the disk fixing hole. The seal may be formed of a magnetic material, a sound absorbing material, or a vibration absorbing material.

[0008]

[Effect] Even if chips or dust generated by machining the hub accumulate in the disc fixing hole, the disc fixing hole penetrates from the end face of the hub to the motor portion. It is possible to easily remove chips, dust and the like from the inside, and it is possible to drastically reduce chips and dust coming out of the disc fixing hole. On the other hand, even if dust or the like is generated from a coil or the like in the motor, the dust or the like can be prevented from being discharged to the outside of the motor by the seal. If the seal is made of a magnetic material, there is an effect of preventing the leakage of magnetic flux from the motor portion to the magnetic disk side,
If the seal is formed of a sound absorbing material or a vibration absorbing material, there is an effect of preventing noise from leaking from inside the motor or an effect of preventing vibration.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a magnetic disk drive according to the present invention will be described below with reference to the drawings. In FIG. 1, the frame 10 has a dish-shaped portion and a boss portion 12 integrally formed at the center thereof, and has a mounting hole 17 at an outer edge portion. A base end of a shaft 52 made of a magnetic material such as iron is fitted and fixed to the inner peripheral side of the boss portion 12. Inner rings 56, 56 of two upper and lower ball bearings 55, 55 are fitted and fixed to the outer periphery of the shaft 52. Outer rings 57, 57 of the ball bearings 55, 55 are
The inner peripheral part of the boss part 24 integrally formed at the center of the center part 0 is fitted and fixed. Thus, the hub 20 is rotatably supported. The hub 20 is for holding and rotating the disk (not shown) integrally, is formed in a substantially cylindrical shape, and has a flange portion 22 for holding the disk on the outer peripheral portion. A cylindrical yoke 15 is fixed to the lower side of the flange 22 by fixing an inward flange formed at an upper end thereof. York 15
Is located inside the dish-shaped portion of the frame 10. A cylindrical drive magnet 30 is fixed to the inner periphery of the yoke 15.

A stator core 33 is fitted and fixed on the outer peripheral side of the boss portion 12 of the frame 10. The stator core 33 has a plurality of salient poles, each salient pole faces the inner peripheral surface of the drive magnet 30, and each salient pole has a coil 32.
Is wound. The stator 31 of the motor unit 5 is constituted by the stator core 33 and the coil 32. The drive magnet 76 constitutes a rotor of the motor unit 5. The motor unit 5 is disposed inside the magnetic disk drive. A notch groove 16 is formed at the lower end of the dish-shaped portion of the frame 10, and a hole 14 is formed in the bottom of the dish-shaped portion of the frame 10 through the bottom in the vertical direction.
Are formed. An insulating paper 36 is disposed inside the bottom of the dish-shaped portion of the frame 10. This insulating paper 3
The coil 32 of the stator 31 is located immediately above 6, and therefore, an insulating paper 36 is provided between the coil 32 and the frame 10.

One end of a flexible wiring board 40 is fixed to the notch 16 at the bottom of the frame 10. A hole 38 is formed in the insulating paper 36 at a position overlapping the hole 14 of the frame 10, and a hole 42 is also formed in the flexible wiring board 40 at a position overlapping the hole 14 of the frame 10. A winding end 34 extends from the coil 32, and the winding end 34 is led out of the motor through the insulating paper 36, the frame 10, and the holes 38, 14, 42 of the flexible wiring board 40. The coil 32 has a plurality of phases, and a plurality of coil winding ends 34 corresponding to the number of phases are led out through the holes 38, 14, 42. Each of the derived coil winding ends 34 is a flexible wiring board 4
0 is connected to each of the soldering lands formed by the solder 44, and each coil 32 is
0 is connected to the external circuit 58.

A ball bearing 55 is provided between the inner peripheral side of the upper end of the boss 24 of the hub 20 and the outer peripheral of the upper end of the shaft 52.
A magnetic fluid seal mechanism 45 is provided for preventing oil mist, dust and the like from being scattered and attached to the magnetic disk. Since the shaft 52 is made of a magnetic material as described above, there is no need to interpose a ring or the like made of a magnetic material between the boss portion 24 and the shaft 52.

At the upper end of the hub 22, there is a shoulder portion formed one step lower than the boss portion 24. From the end surface of this shoulder portion, the disk fixing screw hole 2 is formed toward the motor portion 5.
6, and a hole 28 is formed following the screw hole 26. These disk fixing screw holes 26 and holes 2
8, the hub 20 is penetrated from the end face to the motor section 5. One or a plurality of magnetic disks are stacked on the collar portion 22 of the hub 20 with an appropriate spacer interposed therebetween, and a clamper is further stacked thereon, and a set screw inserted into the clamper is attached to the disk. Screw hole for fixing 2
6, the magnetic disk is integrally fixed to the hub 20. A thin plate-shaped seal 50 is attached to an end surface of the hole 28 on the motor 5 side, that is, a lower end surface of the hub 20.

By forming a screw thread also in the hole 28, the entirety from the upper end to the lower end of the hub 22 may be used as the disk fixing screw hole 26. Further, the seal 50 may be formed of a magnetic material, a sound absorbing material, or a vibration absorbing material.

From the external circuit 58 to the flexible wiring board 4
The current is supplied to the coils 32 of each phase through the wiring pattern 0 and the coil winding end 34, and the power is supplied to the coils 32 of each phase in accordance with the rotational position of the drive magnet 30 constituting the rotor of the motor. By switching, the drive magnet 30 and the hub 20 integral therewith are driven to rotate, and the magnetic disk (not shown) is driven to rotate together with the hub 20.

According to the above-described embodiment, since the disk fixing holes 26 and 28 penetrating from the end face of the hub 20 to the motor portion 5 are formed in the hub 20, chips generated by machining the hub 20 are removed. Even if dust or the like accumulates in the disk fixing holes 26 and 28, the washing of the hub 20 makes it possible to easily remove chips, dirt, and the like in the disk fixing holes 26 and 28. Chips and dust coming out of the fixing holes 26 and 28 can be drastically reduced. Therefore, it is possible to prevent chips and debris coming out of the disk fixing holes 26 and 28 from adhering to the magnetic disk and damaging the magnetic disk and the magnetic head during use of the magnetic disk drive. Reliability can be improved.

On the other hand, even if dust or the like is generated from a coil or the like in the motor, the dust and the like can be prevented from being discharged to the outside of the motor by the seal 50. Furthermore, seal 5
If the magnetic material 0 is formed of a magnetic material, it is possible to prevent the magnetic flux from leaking from the motor unit 5 to the magnetic disk, and if the seal 50 is formed of a sound absorbing material, it is possible to prevent the leakage of noise from inside the motor. Can seal 50
Is formed of a vibration-absorbing material, there is an advantage that vibration can be prevented.

In the illustrated embodiment, the shaft 20 is a fixed shaft motor in which the hub 20 rotates with respect to the fixed shaft 52. However, the present invention is also applicable to a shaft rotating motor in which the shaft rotates together with the hub. Applicable.

[0019]

According to the present invention, the hub is provided with a disk fixing hole penetrating from the end face of the hub to the motor portion, so that chips and dust generated by processing the hub are formed in the disk fixing hole. Even if accumulated, chips and debris in the disk fixing hole can be easily removed by cleaning the hub, and chips and debris coming out of the disk fixing hole after assembling the magnetic disk drive are removed. Can be drastically reduced. Therefore, it is possible to prevent chips and dust coming out of the hole for fixing the disk during use of the magnetic disk drive from adhering to the magnetic disk and damaging the magnetic disk and the magnetic head, thereby reducing the reliability of the magnetic disk drive. Can be enhanced.

On the other hand, even if dust or the like is generated from a coil or the like in the motor, the dust and the like can be prevented from being discharged to the outside of the motor by the seal. Furthermore, if the seal is formed of a magnetic material, it is possible to prevent the magnetic flux from leaking from the motor portion to the magnetic disk side, and if the seal is formed of a sound absorbing material, it is possible to prevent noise from leaking from inside the motor. If the seal is made of a vibration-absorbing material, there is an advantage that vibration can be prevented.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing an embodiment of a magnetic disk drive according to the present invention.

FIG. 2 is a front sectional view showing an example of a conventional magnetic disk drive.

[Explanation of symbols]

 Reference Signs List 5 Motor part 20 Hub 26 Disk fixing hole 28 Disk fixing hole 30 Drive magnet 31 Stator 50 Seal

Claims (4)

(57) [Scope of request for utility model registration] A motor unit having a driving magnet and a stator facing the driving magnet,
In a magnetic disk drive device having a hub for rotating the magnetic disk by rotating the magnetic disk by being fixedly driven by the motor unit, the hub has a magnetic disk penetrating from an end face of the hub to the motor unit. A magnetic disk drive device in which a fixing hole is formed and a seal is attached to an end face of the magnetic disk fixing hole on the motor side. 2. The magnetic disk drive according to claim 1, wherein the seal is formed of a magnetic material. 3. The magnetic disk drive according to claim 1, wherein the seal is formed of a sound absorbing material. 4. The magnetic disk drive according to claim 1, wherein the seal is formed of a vibration absorbing material.