JP2542363Y2 - Voice coil motor with head arm lock mechanism - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a head arm lock for holding a head arm at a predetermined position for preventing the magnetic head of the head arm from contacting the magnetic disk when the magnetic disk drive is not operating. The present invention relates to a voice coil motor with a mechanism.

[0002]

2. Description of the Related Art Conventionally, a voice coil motor with a head arm lock mechanism of this type has a structure as shown in FIGS.
When the voice coil motor of the magnetic disk drive 2 is not operating, the magnetic head 12, the head arm 3, and the drive coil 8 are integrally formed. A small iron piece 9 attached integrally fixes an auxiliary permanent magnet 10 on the lower yoke 5 of the voice coil motor in order to attract and hold the driving coil 8. When the magnetic disk device 2 is not operating, the driving coil 8 Attracted to the auxiliary permanent magnet 10,
It is configured to be retained. In such a conventional structure, a voice coil motor requires an auxiliary permanent magnet 10 which is an additional component or a mounting bracket for the auxiliary permanent magnet, and the number of components is increased. There is a disadvantage that the voice coil motor becomes expensive, for example, it becomes necessary.

[0003]

According to the present invention, in order to eliminate these drawbacks, specific positions of the tips of the upper yoke and the lower yoke forming the voice coil motor are opposed to each other when positioning the drive coil of the magnetic disk drive. A magnetic pole is generated by a permanent magnet that applies a magnetic field to the drive coil disposed on the lower yoke in the opposed gap portion bent and bent, and the small iron piece mounting portion of the drive coil in the non-operating magnetic disk device is attached to the two yoke tips. An inexpensive voice coil motor with a head arm lock mechanism is provided between the gaps by suction and holding by the magnetic poles of the bent portion.

[0004]

According to the present invention, a bent portion is provided at the tip of the outer yoke of each of the lower yoke and the upper yoke of the voice coil motor so as to oppose a part of the yoke, and a magnetic field is applied to the drive coil on the lower yoke. Is applied to the lower yoke and the upper yoke in a magnetic path to form a magnetic pole in the gap at the bent portion. Here, when the magnetic disk drive is not operated, the small iron piece fixed on the drive coil is configured to be attracted and held by the magnetic pole, so that the head arm lock that does not require the auxiliary permanent magnet on the conventional lower yoke is used. It is a voice coil motor with a mechanism.

That is, the present invention provides: An upper yoke, a lower yoke, and a permanent magnet having an N-pole and an S-pole are arranged on the lower yoke surface, and an annularly wound drive coil connected to a head arm for driving a magnetic head is arranged between the permanent magnet and the upper yoke. In the voice coil motor with a head arm lock mechanism for a disk device, a part of the upper yoke and a part of the lower yoke at positions opposite to the head arm mounting position are respectively extended and opposed to bends to form a bent portion having a gap therebetween, A voice coil motor with a head arm lock mechanism, characterized in that a small iron piece that moves integrally with the drive coil in the gap between the bent portions is mounted on the opposite side of the head coil mounting portion of the drive coil. is there. 2. The center of the tip of the bent portion forming the gap into which the small iron pieces are inserted is closest to the head arm lock position on the upper yoke side and the lower yoke side, and is configured to be widened in a tapered shape from side to side. A voice coil motor with a head arm lock mechanism according to claim 1.

[0006]

According to the present invention, bent portions are formed opposite to each other at the ends of an upper yoke and a lower yoke of a magnetic circuit for generating a driving force on a drive coil constituting a voice coil motor, and the drive coils are driven to the two bent end portions. A magnetic pole is generated by the permanent magnet of the magnetic circuit, and a small armature attached to the tip of the drive coil is attracted and positioned in a gap between the two bent portions. The gap between the bent portion of the upper yoke and the lower yoke is the narrowest at the predetermined fixed position, and the tapered left and right space is large, so that the lock position when the head arm is not operating is accurately positioned. I do.

[0007]

1 is a perspective view of a voice coil motor according to the present invention. FIG. 1 shows a permanent magnet 7 and a drive coil 8 which apply a magnetic field to an upper yoke 6, a lower yoke 5, and a drive coil 8 mounted on the lower yoke 5. Shows a small iron piece 9 integrally attached to the small iron piece 9. In the voice coil motor according to the present invention, the bent portions 1 opposed to each other are provided at the tips of the upper yoke 6 and the lower yoke 5 shown in FIG.
1 is formed, small iron pieces 9 made of a soft magnetic material fixed to the drive coil 8 of FIG. 1B enter the gap between the bent portions 11, and the drive coil 8 is attracted and held in the gap between the magnetic poles. Is done. FIG. 2 shows that by changing the shape of the bent portion 11 of the tip of the upper yoke 6 and the lower yoke 5 to form a magnetic scent in the gap between the magnetic poles, the strength of the magnetic pole increases at the position where the interval between the bent portions is closest. The small iron piece 9 of the drive coil 8 is easily attracted, held, and positioned at a predetermined position at the tip of the bent portion. By these operations, the auxiliary permanent magnet conventionally used for fixing the small iron piece of the drive coil becomes unnecessary, and a voice coil motor with a head arm lock mechanism having a simple structure can be realized. The voice coil motor with the head arm lock mechanism according to the present invention can be mounted on a magnetic disk device and a magneto-optical disk device.

[0008]

In order to fix the head arm when the magnetic disk device is not operating, a bent portion is formed at the tip of the lower yoke and the upper yoke constituting the voice coil motor, and a magnetic pole is formed at the tip of the bent portion. An economically advantageous voice coil motor with a head arm lock mechanism that does not require a conventional auxiliary permanent magnet can be provided.

[Brief description of the drawings]

FIG. 1 shows a voice coil motor with a head arm lock mechanism according to the present invention. FIG. 1 (a) is an external perspective view in which a bent portion is formed at the tip of an upper yoke and a lower yoke by a magnetic circuit, and FIG. 1 (b). FIG. 1 is a plan view in which small iron pieces are attached to the same drive coil as in the related art, and FIG. 1C is a side cross-sectional view of the drive coil shown in FIG.

FIG. 2 is a diagram illustrating a magnetic circuit of a voice coil motor, in which a tapered tip is formed in a gap portion of a bent portion at the tip of an upper yoke and a lower yoke, a magnetic gradient is provided, and the strength of a magnetic pole at the center end of the taper FIG. 4 is a perspective view showing another embodiment according to the present invention for heightening and accurately positioning.

FIG. 3 is a plan view showing an outline of a magnetic disk drive.

4A and 4B show a magnetic circuit and a driving coil of a conventional voice coil motor, FIG. 4A is a partially crushed perspective view of the voice coil motor, FIG. 4B is a plan view showing the driving coil,
FIG. 4C is a side sectional view of the drive coil.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Magnetic disk 2 Magnetic disk device 3 Head arm 4 Pivot 5 Lower yoke 6 Upper yoke 7 Permanent magnet 8 Drive coil 9 Small iron piece 10 Auxiliary permanent magnet 11 Bending part 12 Magnetic head 13 Head operation area

Claims (2)

(57) [Scope of request for utility model registration] An upper yoke, a lower yoke, and a permanent magnet having N poles and S poles on the lower yoke surface, and a circularly wound drive connected to a head arm for driving a magnetic head between the permanent magnet and the upper yoke. In a voice coil motor with a head arm lock mechanism for a disk drive having a coil disposed therein, a part of an upper yoke and a part of a lower yoke at positions opposite to the head arm mounting position are respectively extended and opposed to bend, and a bend is formed to provide a gap therebetween. A head arm lock, wherein a small iron piece that moves in a gap between the bent portions is integrally attached to the drive coil on the side opposite to the head arm attachment portion of the drive coil. Voice coil motor with mechanism. 2. A central portion of a bent portion forming a gap into which a small iron piece is inserted is closest to a head arm lock position on an upper yoke side and a lower yoke side, and is configured so as to be tapered to the left and right. 2. The voice coil motor with a head arm lock mechanism according to claim 1, wherein: