JPH04355242A - Magneto-optical disk device - Google Patents

Abstract

PURPOSE:To prevent the relative positions of the optical head and magnetic head of the magneto-optical disk independently provided with these two heads from shifting to a specified range or above even if impact is applied thereon from the outside. CONSTITUTION:A guide cylinder 22d is provided at the bottom end of a photodetecting part 22 fixed to the magnetic head 8 and is put on the cylindrical part 21b of the photodetecting part 21 fixed to the optical head 6. The guide cylinder 22d comes into contact with the cylindrical part 21b and regulates the movement even if the impact is applied to the heads from the outside. The relative positions of the optical head 6 and the magnetic head 8 are thus prevented from shifting.

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 device for recording and reproducing information on a magneto-optical recording medium.

0002

2. Description of the Related Art A magneto-optical disk device has a mechanism in which an optical head and a magnetic head for recording information on a magneto-optical disk move independently of each other, as shown in FIG. A semiconductor laser light source 4 is placed below the recording disk 3 fixed by the
An optical head 6 for recording and reproducing having a condenser lens 5 is disposed, and a magnetic head 8 having a coil 7 for applying a magnetic field during recording is disposed above the recording disk 3.

Further, the optical head 6 and the magnetic head 8 are movable in the radial direction of the recording disk 3 independently of each other, and each of the optical head 6 and the magnetic head 8 is provided with a laser drive circuit 9.
and a magnetic signal drive circuit 10, and are controlled so that signals from an information source (not shown) can be recorded. Further, the optical head 6 and the magnetic head 8 are provided with a sensor for detecting their relative positions, so that it can be confirmed whether the focal position of the laser beam and the position of the coil 7 accurately match.

That is, this sensor is composed of a light emitting section 11 provided on the optical head 6 and a light receiving section 12 provided on the magnetic head 8, and the light emitting section 11 and the light receiving section 12 are arranged opposite to each other. When the positions of the optical head 6 and the magnetic head 8 are precisely aligned, the center lines of the light emitting section 11 and the light receiving section 12 overlap. An arithmetic circuit 14 for detecting relative positions in conjunction with a magnetic head drive circuit 13 is connected to the light emitting section 11 and the light receiving section 12, so that the relative positions of the optical head 6 and the magnetic head 8 always match. is controlled by. As shown in FIGS. 17 and 18, the light emitting section 11 has a built-in LED 11a that emits infrared light, and the light receiving section 12 has light receiving elements 1 divided in the radial direction of the disk.
2a and 12b are provided.

[0005] When recording data, the recording disk 3
rotates, and the optical head 6 is tracked to the recording track. At this time, the position of the magnetic head 8 is precisely controlled by the magnetic head drive circuit 13 and the arithmetic circuit 14 so that the light receiving section 12 is directly above the light emitting section 11, and thereby the condenser lens 5 is positioned with the recording disk 3 in between. The coils 7 will be exactly facing each other. The data to be recorded is sent to the laser drive circuit 9 and the magnetic signal drive circuit 10, and in response, the semiconductor laser light source 4 emits light, the coil 7 is excited, and the data is recorded.

In the above-mentioned magneto-optical disk device, when an external force such as vibration or impact acts on the device and a relative position shift occurs that exceeds the detection capability of the light receiving section 12 as shown in FIG. Control of the position of the head 8 becomes virtually impossible. In such a case, as shown in FIG.
It is necessary to move the optical head 6 in an arbitrary direction until the light beam from the optical head 1 enters the light receiving section 12 and the arithmetic circuit 14 becomes operational.

Alternatively, as shown in FIG. 21, the optical head 6
Home position protrusions 15a, 15b are provided on the outer circumferential ends of the magnetic head 8, respectively, and home position sensors 16a, 16b matching these are provided outside the recording disk 3. After initializing the head position by moving as shown in 22, the heads 6 and 8 are moved again to the track on the recording disk 3,
A method of re-recording is being adopted.

[0008]

[Problem to be Solved by the Invention] However, in the above-mentioned conventional example, due to vibrations etc. applied to the device from the outside,
If the positions of the two heads 6, 8 are greatly deviated, it is necessary to move one head to initialize the relative position of both heads 6, 8, or to move both heads 6, 8 to the absolute position. Therefore, it takes time to restart the recording operation, and it is necessary to provide home position sensors 16a and 16b, which also leads to an increase in costs.

SUMMARY OF THE INVENTION An object of the present invention is to provide a magneto-optical disk device that does not cause large head misalignment regardless of the state of use of the device.

0010

[Means for Solving the Problems] A magneto-optical disk device according to the present invention for achieving the above object is a magneto-optical disk device in which an optical head and a magnetic head are arranged with a recording medium in between. It has a detection means for detecting the relative position of the magnetic head, and a movement control means for the optical head and the magnetic head, and an allowable range of the relative position of the optical head and the magnetic head is an effective detection range of the detection means. The invention is characterized in that both heads are provided with relative position regulating guides that fit within the head.

[0011]

[Operation] In the magneto-optical disk device having the above-described structure, the relative positions of the optical head and the magnetic head are always within the effective range of the detection means by the relative position regulating guide, and these relative positions are reliably controlled.

0012

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained in detail based on embodiments shown in FIGS. 1 to 15. Note that the same reference numerals as in the conventional example indicate the same members.

FIG. 1 is a block diagram of the first embodiment, and FIG.
3 is a cross-sectional view of the relative position detection section, and FIG. 3 is a plan view. An optical head 24 for recording and reproducing information is disposed below the recording disk 3 fixed to the spindle motor 1 by a clamper 2.
A magnetic head 5 that applies a magnetic field during recording and is movable in the axial direction is disposed above the recording disk 3, and the optical head 6 and the magnetic head 8 are movable in the radial direction of the recording disk 3 independently of each other.

A light emitting section 21 is provided at the outer peripheral end of the optical head 6. As shown in FIGS. 2 and 3, the light emitting section 21
A cylindrical part 21b provided with a rectangular slit 21a is provided to protrude upward, and an LED 2 is installed inside the cylindrical part 21b.
1c is built-in.

The magnetic head 8 is provided with a coil 7 for applying a magnetic field, and a light receiving section 22 is provided at the end thereof. This light-receiving section 22 is provided with a columnar section 22a facing downward, and on its lower surface are two divided light-receiving elements 22b, 22.
cylindrical portion 22a is arranged at the bottom of the cylindrical portion 22a.
A guide tube 22d having the same outer diameter as the guide tube 22d is provided. The tip of the cylindrical portion 21b of the light emitting portion 21 is always inserted into the guide tube 22d. Further, when the cylindrical portion 21b is inscribed inside the guide tube 22d, a 2×1 gap is created between them, as shown in FIGS. 4 and 5.

When the optical head 6 and the magnetic head 8 face each other correctly, the central axes of the cylindrical portion 21b and the light receiving portion 22 coincide. If a deviation occurs, the arithmetic circuit 14 generates an output proportional to the difference between the output voltages of the two light receiving elements 22b and 22c, thereby controlling the magnetic head 8.

The relative position detection operation will now be described. As shown in FIG. 6, the light beam emitted from the LED 21c is emitted in a rectangular shape due to the slit 21a. Since the area of the slit 21a is small with respect to the light receiving elements 22b and 22c that receive the light flux, a relative positional error between the cylindrical portion 21b and the light receiving portion 22 appears as a difference in light receiving area between the elements 22b and 22c. Since the output voltages of the elements 22b and 22c are proportional to the light receiving area, the output voltages Vb and V of each element 22b and 22c are
c is the element 2 when the relative position error is 0 as shown in FIG.
The outputs Vb and Vc of 2b and 22c match. Furthermore, when shifted to the left or right, the output of one of the elements becomes larger, and the difference between the outputs of each element of the arithmetic circuit 14 becomes Vb - Vc.
As shown in FIG. 8, the output changes significantly in positive and negative directions in proportion to the error around 0 relative error.

As shown in FIG. 2 and FIG.
The output is 0, and the magnetic head 8 does not move. When the optical head 6 moves and the light emitting section 21 moves as shown in FIGS. 4 and 5, a large output is generated in the arithmetic circuit 14, and the magnetic head 8 is driven and returned to the neutral position.

When a large external force such as an impact is applied to the magneto-optical disk device, the optical head 6 and magnetic head 8 may be shaken considerably, but the cylindrical portion 21b of the light emitting portion 21 serves as a guide for the light receiving portion 22. It collides with the inner wall of the tube 22d, and the positions of the two do not shift any further. Therefore,
The relative position of the optical head 6 and the magnetic head 8 does not become unclear, and there is no need to initialize the relative position or move the magnetic head 8 in any direction, thereby reducing the time during which the device cannot be used.

FIG. 9 is a block diagram of a mechanism for ejecting the recording disk 3 from the magneto-optical disk device, and FIG. 10 is an explanatory diagram of the operation. An optical head brake groove 23 having a continuous tooth shape is provided on the lower surface of the optical head 6 in the radial direction of the disk 3.
Further, magnetic head brake grooves 24 of the same shape are provided on the upper surface of the magnetic head 8, and each head 6 is aligned with these grooves.
, 8 are provided in the apparatus. An optical head brake 25 and a magnetic head brake 26 are provided in the apparatus.

During the ejection operation of the recording disk 3,
First, the clamper 2 is released and the recording disk 3 is moved upward. At this time, the magnetic head 8 is retracted upward so that the magnetic head 8 does not collide and interfere with the ejection operation. When the magnetic head 8 is sufficiently retracted, the magnetic head brake 26 engages with the magnetic head brake groove 24 of the magnetic head 8, and the magnetic head 8 is fixed.

At the same time, the optical head brake 25 rises from below the optical head 6 and the magnetic head brake groove 24
The optical head 6 is also fixed. Recording disc 3
is discharged to the outside of the device by securing the space necessary for discharge. The operation of the arithmetic circuit 14 stops after the recording disk 3 is ejected, but since the optical head 6 and the magnetic head 8 are fixed, their relative positions do not change even if an impact is applied, and recording starts. The loss time until

FIGS. 11 to 15 show a second embodiment, with FIG. 11 being a configuration diagram and FIGS. 12 and 13 being sectional views of the relative position detection section. In this second embodiment, the guide tube 22d provided in the light receiving section 22 in the first embodiment is removed, and in its place a downwardly directed guide pin 22f is provided on the horizontal protrusion 22e. The light emitting portion 37 is provided with a horizontal protrusion 21d, and the protrusion 21d has a radial width of 2.
A x1 guide hole 21e is provided.

During operation of the device, the guide pin 22f and the guide hole 21e are aligned to restrict relative displacement in the radial direction between the light receiving section 22 and the light emitting section 21. Even if a large external force is applied to the device and a large deviation occurs in the relative positions of the light receiving section 22 and the light emitting section 21, the guide pin 22f and the guide hole 21e come into contact with each other, and the positional deviation is regulated.

FIGS. 14 and 15 are explanatory views of the recording disk ejection operation, which is similar to the first embodiment, but in this case, the guide pin 2 of the light receiving section 22 is
2f is extracted from the guide hole 21e of the light emitting part 21. Furthermore, even when the recording disk 3 is ejected, the light receiving section 22
Since the light emitting section 21 is fixed by the brake, no positional deviation occurs.

[0026]

Effects of the Invention As explained above, the magneto-optical disk device according to the present invention has a structure in which the positions of the optical head and the magnetic head do not deviate beyond a certain range in the relative position detecting section, so that external shocks can be avoided. Even if a disturbance occurs to the device, the time for recovery to an operable state is shortened, and a highly reliable magneto-optical disk device can be manufactured.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of a first embodiment.

FIG. 2 is a sectional view of a relative position detection section.

FIG. 3 is a plan view of a relative position detection section.

FIG. 4 is a cross-sectional view of a state where the light emitting part and the light receiving part are shifted.

FIG. 5 is a plan view of a state where the light emitting part and the light receiving part are shifted.

FIG. 6 is a cross-sectional view of a light receiving unit irradiated with a light beam from a light emitting unit.

FIG. 7 is a characteristic diagram of the light-receiving sensitivity of the light-receiving sensor.

FIG. 8 is a characteristic diagram of the output of the arithmetic circuit.

FIG. 9 is a configuration diagram of a recording disk ejection mechanism.

FIG. 10 is an operation explanatory diagram.

FIG. 11 is a configuration diagram of a second embodiment.

FIG. 12 is a cross-sectional view of the light emitting section and the light receiving section facing each other.

FIG. 13 is a cross-sectional view of a state where the light emitting part and the light receiving part are shifted.

FIG. 14 is an explanatory diagram when a recording disk is ejected.

FIG. 15 is an explanatory diagram when a recording disk is ejected.

FIG. 16 is a configuration diagram of a conventional magneto-optical disk device.

FIG. 17 is a sectional view of a main part of a conventional relative position detection section.

FIG. 18 is a plan view of the relative position detection section.

FIG. 19 is an explanatory diagram of a conventional state in which both heads are misaligned.

FIG. 20 is an explanatory diagram of a conventional method for initializing the relative positions of both heads.

FIG. 21 is an explanatory diagram of another example of a conventional state in which both heads are shifted.

FIG. 22 is an explanatory diagram of a conventional method for initializing the relative positions of both heads.

[Explanation of symbols]

1 Spindle motor 2 Clamper 3 Recording disc 4 Semiconductor laser light source 6 Optical head 7 Coil 8 Magnetic head 14 Arithmetic circuit 21 Light emitting part 21a Square slit 21b Cylindrical part 21c LED 22 Light receiving section 22b, 22c Photo receiving element 22d Guide tube 23, 24 Brake groove 25, 26 Brake

Claims (4)

[Claims] 1. A magneto-optical disk device in which an optical head and a magnetic head are arranged with a recording medium interposed therebetween, comprising: a detection means for detecting relative positions of the optical head and the magnetic head; and movement control of the optical head and the magnetic head. means, wherein both heads are provided with relative position regulation guides such that a permissible range of relative positions between the optical head and the magnetic head falls within an effective detection range of the detection means. Magnetic disk device. 2. The magneto-optical disk device according to claim 1, wherein the relative position regulating guide is separable along with the heads in a direction perpendicular to the recording medium. 3. The magneto-optical disk device according to claim 2, further comprising a brake mechanism that restrains movement of both the heads in a radial direction when the recording medium is ejected from the magneto-optical disk device. 4. Claim 3, wherein the operation of the relative position detection means is stopped after the operation of the brake mechanism is completed.
The magneto-optical disk device described in .