JPH04241280A - Magneto-optical disk recording/reproducing device - Google Patents

Abstract

PURPOSE:To prevent a flying head from being damaged even when a disk whose surface is not coated is loaded into the magneto-optical disk recording/ reproducing device to which the flying head is applied. CONSTITUTION:A disk 1 is discriminated in its kind as to whether it is coated or not. Based on a result of this discrimination, the flying head 5 is moved by using a head elevating device 26 in the separating or abutting direction from or against the surface of the disk 1.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magneto-optical disk recording/reproducing apparatus.

0002

2. Description of the Related Art A magneto-optical disk recording/reproducing apparatus using a flying head has been proposed. In a magneto-optical disk recording/reproducing device using a flying head, as shown in FIG.
A pickup 53 is disposed on the lower surface side of 1. The pickup 53 is provided with an objective lens (not shown) whose position is controlled by a focus/tracking servo. A magnetic head 54 is arranged on the upper surface side of the disk 51 . The magnetic head 54 is a flying head.

When the disk 51 is rotated, the disk 5
1, an air current A is generated, and a levitation force is generated on the magnetic head 54. Therefore, there is a gap between the disk 51 and the magnetic head 54.
A gap d of approximately 0 microns is created. It is best for the disk surface and the magnetic head to be close to each other and at a constant distance. This gap d allows the magnetic head 54 to efficiently apply a magnetic field to the disk 51.

0004

[Problems to be Solved by the Invention] In a magneto-optical disk recording/reproducing apparatus using such a flying head, the disk 51 is
It is necessary to coat the surface of 1.

On the other hand, the surface of a conventional disk is not coated and has irregularities. Therefore,
Depending on how the magnetic layer is made, some disks have a coated surface and are compatible with flying heads, while others have uncoated surfaces and are not compatible with flying heads.

[0006] When a disk whose surface is not coated is mounted in a magneto-optical disk recording/reproducing apparatus using a flying head, the surface of the disk is uneven, so that it is difficult to generate a levitation force on the magnetic head. Therefore, there is a risk that the disk surface and the magnetic head will come into contact and damage the flying type magnetic head.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a magneto-optical disk recording/reproducing apparatus that can prevent a flying type magnetic head from being damaged even when a disk whose surface is not coated is mounted.

[0008]

[Means for Solving the Problems] The present invention provides a magneto-optical disk recording system having a drive means for determining the type of disk and moving a flying head in directions toward and away from the disk surface based on the determination result. It is a playback device.

[0009]

[Operation] The disc type information recorded in advance on the disc control track is detected, and the type of the loaded disc is determined. For uncoated discs, the flying head is moved away from the disc surface.

0010

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an outline of a head of a magneto-optical disk recording/reproducing apparatus to which the present invention is applied. In FIG. 1, 1 is a disk, 2 is a spindle motor that rotates the disk, and 3 is a pickup. The optical system of the pickup 3 houses a light emitting source, a light receiver, an objective lens, and the like. The pickup 3 is arranged at one end of the arm 4. 5 is a magnetic head, which is a flying head. The magnetic head 5 is arranged at one end of the gimbal 6.

FIG. 2 is a sectional view of the arm 4, gimbal 6, and their surrounding parts. As shown in FIG. 2, the other end of the arm 4 is provided with a protrusion 4A. A coil 10 is wound around the protrusion 4A. A current is applied to the coil 10 from the outside. An iron piece 9 is attached to the other end of the gimbal 6. An iron core 7 is disposed between the other end of the arm 4 and the other end of the gimbal 6. One end of the iron core 7 is buried in the protrusion 4A, and the other end passes through the gimbal 6 and the iron piece 9. Further, a coil spring 8 is provided around the iron core 7.

When no current is applied to the coil 10, the extension force of the coil spring 8 causes the protrusion 4A and the iron piece 9 to be separated from each other. Therefore, when the disk 1 is loaded, the magnetic head 5 is located away from the disk surface of the disk 1. When a current is passed through the coil 10, the coil 1
0, an electromagnetic force is generated, and the iron piece 9 is drawn toward the protrusion 4A. Then, the iron piece 9 approaches the protrusion 4A. Therefore, when the disk 1 is loaded, the magnetic head 5 approaches the disk surface of the disk 1. That is, disk 1
The distance between the magnetic head 5 and the magnetic head 5 can be controlled by the current flowing through the coil 10.

FIG. 3 is a block diagram showing the overall configuration of a magneto-optical disk recording/reproducing apparatus to which the present invention is applied. 1 is a disk, 2 is a spindle motor that rotates the disk 1, and 3 is an optical pickup. The spindle motor 2 is controlled by a spindle servo 14. The pickup 3 is provided with an objective lens, a beam splitter, a laser diode, and the like. pickup 3
The optical system is controlled by a focus/tracking servo 15 and a laser driver 20. Further, the pickup 3 is moved in the radial direction along the track of the disk 1 by a thread feed motor 16. The thread feed motor 16 is controlled by a thread servo 17. The magnetic head 5 is movable vertically with respect to the disk surface by a head elevating device 26. As shown in FIGS. 1 and 2, the head elevating device 26 is composed of a coil spring 8, a coil 10, and the like.

During reproduction, the information on the disc 1 is reproduced by the pickup 3. Pickup 3 output is RF
The signal is supplied to the amplifier 21. RF amplifier 21 amplifies the RF signal. The output of the RF amplifier 21 is supplied to a PLL circuit 22 and also to a demodulation circuit 23. PLL
A clock signal is regenerated by circuit 22. The output of the PLL circuit 22 is demodulated by a demodulation circuit 23. The output of demodulation circuit 23 is supplied to decoder 24 . Decoder 24
Then, error correction and error detection processing is performed.

During recording, data is input to the engoder 27. The encoder 27 performs error correction encoding of data. The output of the encoder 27 is supplied to a modulation circuit 28 and modulated by 2-7 modulation, 4/15 modulation, NRZ-I modulation, or the like. A clock signal is supplied from the PLL circuit 22 to the modulation circuit 28 . The output of the modulation circuit 28 is supplied to a phase compensation circuit 29. The head driver 30 is driven by the output of the phase compensation circuit 29. At the same time, a laser drive signal is supplied from the system controller 19 to the laser driver 20 . laser driver 20
A clock signal is supplied from the PLL circuit 22. The pickup 3 is driven intermittently by the output of the laser driver 20.

Disc 1 contains information about the disc itself, such as disc type, recording conditions, sector size/number, and whether or not it is a coated disc, in advance on the innermost, outermost, or outermost track. Inner and outer circumference (hereinafter referred to as
control area).

When the power is turned on and the disk 1 is loaded, the pickup 3 is moved by the thread feed motor 16.
is moved to the control area of disk 1. The system controller 19 determines the type of disc 1, that is, whether it is a coated disc or an uncoated disc, from the information read from the control area. When it is determined that the disk 1 is not coated, a drive signal is supplied from the system controller 19 to the driver 25, and the head lifting device 2
6 is driven. The magnetic head 5 is lifted upward by a head lifting device 26. In this way, even if an uncoated disk is loaded, the magnetic head 5 does not come into contact with the disk 1, so damage to the magnetic head 5 is prevented. On the other hand, if it is determined that the disk 1 is coated, the magnetic head 5
is located close to the disk 1.

FIG. 4 shows another embodiment of the invention. In FIG. 4, 41 is a disk, 42 is a spindle motor for rotating the disk 41, and 43 is a pickup for reading data from the disk 41. In FIG. The pickup 43 houses a light emitting source, a light receiver, an objective lens, and the like. 31 is an arm with a pickup 43 disposed at its tip. Reference numeral 5 denotes a magnetic head, which is disposed at one end of the gimbal 36. The other end of the arm 31 and the other end of the gimbal 36 are joined, and the pickup 43 and magnetic head 5 move together in the radial direction of the disk 41.

32 is a lift plate. The lift plate 32 is for lifting the gimbal 36 upward. One end of lift plate 32 is coupled to electromagnetic plunger 33. A spring member 34 is disposed near the middle portion of the lift plate 32. In addition, the lift plate 32
A roller 35 is arranged on the other end side.

When an uncoated disk is loaded in such a magneto-optical disk recording/reproducing apparatus, the electromagnetic plunger 33 is driven and the lift plate 32 is moved upward. Therefore, the magnetic head 5
is spaced apart from the disk surface of the disk 41. Note that if the roller 35 is not provided on the lift plate 32,
Gimbal 36 and lift plate 32 come into contact. Therefore, upward movement of the gimbal 36 becomes unstable. Further, when the pickup 43 and the magnetic head 45 are moved together in the radial direction of the disk 41, the gimbal 36 is moved while contacting the lift plate 32. For this reason,
Movement of the gimbal 36 becomes unstable. However, in this embodiment, since the roller 35 is provided on the other end side of the lift plate 32, the gimbal 36 can move smoothly.

In the above embodiment, electromagnetic force or rollers are used to move the gimbals 6, 36, but the invention is not limited to these. For example, a piezoelectric element may be disposed on the gimbal, and the piezoelectric element It is also possible to use the inverse piezoelectric effect, which applies a voltage to.

[0023]

[Effects of the Invention] As explained above, according to the magneto-optical recording and reproducing apparatus according to the present invention, information on the disc type recorded in advance on the control track of the disc is detected, and the type of the loaded disc is determined. . If the disk is not compatible with a flying head, the flying head is moved in a direction away from the disk surface. Therefore, even if a disk whose surface is not coated is mounted, damage to the flying magnetic head can be prevented. Recording and playback can be performed on disks that are compatible with flying heads, and playback can be performed on disks that are not compatible with flying heads.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an embodiment of the present invention.

FIG. 2 is a sectional view of one embodiment of the invention.

FIG. 3 is a block diagram of an embodiment of the invention.

FIG. 4 is a perspective view of another embodiment of the invention.

FIG. 5 is a diagram used to explain a conventional example.

[Explanation of symbols]

5 Magnetic head 7 Iron core 8 Coil spring 9 Iron piece 10 Coil 35 Roller

Claims (1)

[Claims] 1. A magneto-optical disk recording/reproducing apparatus comprising a drive means for determining the type of disk and moving a flying head in directions toward and away from the disk surface based on the determination result.