JP2793059B2 - Floating magnetic head for magneto-optical recording / reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flying magnetic head in a magneto-optical recording / reproducing apparatus for recording / reproducing information by using a laser beam.

[0002]

2. Description of the Related Art In recording on a magneto-optical recording medium, FIG.
As shown in the figure, the magnetic recording film 7 is irradiated with laser light LB and heated, thereby reducing the coercive force of the magnetic recording film 7,
In this state, by applying an external magnetic field, the direction of magnetization of the magnetic recording film 7 is changed, and information is erased and written. As a means for applying the external magnetic field, for example, a pot-shaped magnetic head 4 is used, and the direction of the applied magnetic field is easily changed by the direction of the current flowing through the coil of the pot-shaped magnetic head 4, whereby the information to the magneto-optical disk 3 is obtained. Can be overwritten.

However, when the pot-shaped magnetic head 4 is used, the magnetic flux from the magnetic head needs to be equal to or greater than the coercive force of the magnetic recording film when heated on the magnetic recording film. It is necessary to approach the magneto-optical disk 3. However, in the conventional magneto-optical recording / reproducing apparatus, the pot-shaped magnetic head 4 does not follow the run-out of the magneto-optical disk 3 but is placed at a distance of 1 mm of run-out of the magneto-optical disk + a margin (for example, 0.2 mm). ing. As described above, since the distance between the magneto-optical disk 3 and the pot-shaped magnetic head 4 is large, the magnetic field must be increased.

As a means for solving this problem, there is a floating type control method. The principle of the floating magnetic head is to maintain a small gap between the magnetic head and the recording medium by using the dynamic pressure generated by the viscosity of air when the magnetic head and the recording medium move relatively at high speed. This uses a gas-lubricated bearing that causes the magnetic head to follow the runout of the magneto-optical disk. FIG. 7 shows an example of a flying magnetic head. The flying slider 2 provided with the magnetic head 21 is pressed against the disk surface by the support spring 23 with a force of several tens to one hundred and several tens mN. In this state,
When the disk is rotated in the B direction, the floating slider 2 is floated by the air film floating according to the above floating principle. The above method is a contact start / stop method in which the flying slider contacts the disk surface before flying.

[0005]

The floating magnetic head is C
When used at a very low rotation, such as D standard, the generated air pressure becomes small, and the spring force of the support spring and the air pressure are not balanced, so use a slider support spring with a small spring constant. And the flying state of the slider becomes unstable.

[0006]

SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a position control arm that moves in the track direction of a magneto-optical disk according to a recording position, a coil and a coil fixed to the position control arm. A magnetic head composed of a core that freely moves inside, and a floating slider / support spring having one end fixed to the periphery of the magnetic head or to the position control arm and the core fixed to the free end at the other end. Prepare.

[0007]

Since only the core of the magnetic head and the flying slider / support spring are levitated, the load applied to the flying slider / support spring is reduced.

[0008]

An embodiment of the present invention will be described with reference to FIG. The magneto-optical disk 3 as a recording medium includes a disk substrate 6 made of polycarbonate resin, a magnetic recording layer 7, and a protective film 8. An optical head 9 is arranged below the magneto-optical disk 3. Semiconductor laser 1 in optical head 9
0 indicates a continuous oscillation and a substantially constant intensity DC laser beam LB.
And the direction of the laser beam LB is changed by 90 ° by the beam splitter 12. The laser beam LB passing through the objective lens 11 is condensed near the recording position of the magnetic recording film 7 of the magneto-optical disk 3 and is provided for heating for magneto-optical recording. The magneto-optical disk 3 which reads the difference in the magnetization direction of the magnetic recording layer 7
The reflected light R-LB from the laser beam passes through the objective lens 11, the beam splitter 12, and the polarizer 13, enters the optical sensor 14, and is provided for focus servo, tracking servo, and magneto-optical signals.

On the other hand, a magnetic head 20 is arranged above the magneto-optical disk 3. The magnetic head 20 includes a back core 15, a coil 16, and a core 17. The back core 15 and the coil 16 are fixed to the position control arm 1 that follows the recording position of the magneto-optical disk 3, and the core 17 is fixed to a free end, which is one end of a floating slider / support spring 18, and a floating slider / support spring. The other end of 18 is fixed to a spring support 19 fixed to the position control arm 1. As a result, the core 17 can freely move at the center of the coil 16.

Next, the floating operation will be described with reference to FIG. When the magneto-optical disk 3 is at rest, the free end of the flying slider / support spring 18 is in contact with the magneto-optical disk 3. In this state, when the magneto-optical disk 3 is rotated in the direction A, the flying slider and support spring 18 entrains the airflow C and floats according to the above-described floating principle, and the surface of the magneto-optical disk 3 is prevented from oscillating. Follows while maintaining a certain minute gap.

Next, the state of generation of a magnetic field of the magnetic head when the flying slider / support spring follows the runout of the magneto-optical disk will be described with reference to FIGS. As shown in the figure, the core and the floating type slider / support spring follow the surface deflection of the magneto-optical disk while maintaining a certain gap, and as a result, the core moves in the vertical direction of the magneto-optical disk surface. Also, it can be seen that a magnetic field of a constant intensity a or more is constantly applied to the magneto-optical disk surface.

FIG. 2 shows an example of a modification of the magnetic head. As shown in the figure, a columnar floating core is also effective. or,
Although it is possible to omit the back core 15 shown in FIG. 1 from the constituent members, it is desirable to have the back core 15 in consideration of the magnetic field strength. The material of the flying slider / support spring is preferably a non-magnetic material. Furthermore, if the flying slider / support spring is coated with a resin or the like having a low friction coefficient at a portion where the flying slider / support spring contacts the magneto-optical disk, the magneto-optical This is effective for improving the reliability of the disk.

[0013]

According to the present invention, the same level of control as a flying magnetic head can be performed even on a low-rotation magneto-optical disk such as the CD standard. Even if only the core is levitated, it is possible to generate a magnetic field of the same degree as when the entire magnetic head follows the runout of the magneto-optical disk. Further, only the core is levitated, the inertia is smaller than that of the conventional levitated magnetic head, and the reliability of the apparatus against vibration is improved.

[Brief description of the drawings]

FIG. 1 is a structural view schematically showing the vicinity of a floating magnetic head according to the present invention.

FIG. 2 is a structural view showing deformation of a core.

FIG. 3 is a magnetic field analysis simulation diagram of the magnetic head when the core moves downward.

FIG. 4 is a magnetic field analysis simulation diagram of the magnetic head when the core is at a fixed position.

FIG. 5 is a magnetic field analysis simulation diagram of the magnetic head when the core moves upward.

FIG. 6 is a structural diagram schematically showing the vicinity of a conventional pot-shaped magnetic head.

FIG. 7 is a structural view schematically showing the vicinity of a conventional floating magnetic head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Position control arm 3 Magneto-optical disk 16 Coil 17 Core 18 Flying slider and support spring 20 Magnetic head

Claims (1)

(57) [Claims] 1. A floating magnetic head of a magneto-optical recording / reproducing apparatus that irradiates a magneto-optical disk with a laser beam and modulates a magnetic field with recording information to record information on the magneto-optical disk, according to a recording position. A magnetic head including a position control arm that moves in the track direction of the magneto-optical disk, a coil fixed to the position control arm, and a core that freely moves in the coil; and a periphery of the magnetic head or the position control arm A floating slider / support spring having one end fixed to the other end and the core fixed to the other end, and the core and the floating slider / support spring follow the runout of the magneto-optical disk. A floating magnetic head characterized by the following.