JP2770881B2 - Magnetic recording device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a technique for controlling a contact state between a magnetic head and a magnetic recording medium in a magnetic recording type recording apparatus.

2. Description of the Related Art In a recording / reproducing apparatus using a magneto-optical recording method, particularly when performing modulation using a magnetic field, the modulation frequency (reversal time of the magnetic field) is fast. The head needs to be very close to the medium. Its size is required to be several tens μm or less. Such a gap is less than the surface runout of the disk or the assembly accuracy of the apparatus, and a method of mechanically fixing the magnetic head cannot be adopted. Therefore, conventionally, the magnetic head was hydrodynamically levitated on the surface of the recording medium at the required minute gap,
A flying head slider or the like has been devised which always keeps a constant gap following a surface runout.

[Problems to be Solved by the Invention] However, since the magneto-optical recording medium is manufactured so as to be portable, it is inevitable that dust, dust and the like adhere to the medium surface. Therefore, the adhering matter is caught between the magnetic head and the medium surface, so that the surface of the medium is scratched. In the case of a flying head, a head crash (head destruction) occurs, and the life of the medium is shortened. Was.

In addition, there is also a problem that accurate recording cannot be performed due to a defect of an applied magnetic field due to adhesion of dust, dust, or the like, and the reliability of the apparatus is reduced.

SUMMARY OF THE INVENTION It is an object of the present invention to constantly manage the contact state between a magnetic head and a recording medium, reduce the degree of damage and destruction of the medium surface by the magnetic head, extend the life of the medium, and always perform accurate recording. It is to provide a magnetic recording device which can be used.

Means for Solving the Problems In order to achieve the above object, a magnetic recording apparatus according to claim 1 of the present invention uses a means for detecting a contact state between an information recording medium surface and a magnetic head (hereinafter referred to as a contact state). State detecting means), means for pressing the magnetic head in a direction substantially perpendicular to the information medium surface, and means for controlling the pressing force according to the output of the contact state detecting means. And

In the magneto-optical recording apparatus according to a second aspect of the present invention, the contact state detecting means includes an element for observing an AE (acoustic emission) caused by a contact between the information recording medium surface and the magnetic head. And

When dust or dust adhering to the media is caught in the magnetic head between the media, AE is generated due to local destruction of the media surface, attached matter, and the magnetic head. You can know. In the case of a magnetic head mounted on a flying head slider, the flying height (gap between the medium and the slider) changes depending on the pressing force on the magnetic head. That is, the pressing force and the flying height are in an inversely proportional relationship. By increasing the gap between the magnetic head and the medium,
The probability of head crashes caused by dust and dust adhering to the medium can be reduced, but the increased flying height reduces the rigidity of the air film, resulting in unstable flying conditions, which in turn causes head crashes Probability increases.

The adhesion of dust and dust and its condition are specific to the medium,
Setting a high flying height from the beginning is disadvantageous in terms of flying stability, but according to the method of the present invention, the optimum flying height,
That is, it is possible to maintain the lowest head crash occurrence state.

[Operation] As shown in FIG. 1, the magnetic recording apparatus according to the first aspect of the present invention detects the contact state between the magnetic head and the recording medium by sound or other means by the contact state detection sensor 40.
Obtain a current or voltage signal P1. Its current or voltage signal
After P1 is amplified by the amplifier 41 to be a signal P2, it is input to the controller 42. The controller 42 refers to the information in the storage unit 43 in which information for optimally controlling the gap between the magnetic heads according to the signal P2 is recorded, and refers to the pressing mechanism driving circuit 44.
The drive signal P3 is issued. The pressing mechanism drive circuit 44 outputs a signal
The magnetic head pressing mechanism 45 is driven by P3, and as a result, the gap is controlled so that a head crash does not occur.

According to a second aspect of the present invention, there is provided a magnetic recording apparatus having an element for observing acoustic emission (AE) generated by contact between a magnetic head and a medium on a magnetic head or a member supporting the magnetic head, and according to the contact state. The contact state is managed by changing the force for urging the magnetic head against the recording medium.

EXAMPLES Hereinafter, the magnetic recording apparatus of the present invention will be described in detail based on specific examples.

FIG. 1 is a schematic block diagram of a magnetic recording apparatus according to the present invention. In FIG. 1, 40 is a contact state detection sensor such as an AE sensor, 41 is an amplifier for amplifying a signal from the sensor 40, 42
Is a controller for controlling the system, 43 is the sensor 40
When a signal to be sent to the pressing mechanism drive circuit 44 is determined in accordance with a signal from the controller, storage means for storing a storage table used for the determination, 44 is a pressing mechanism drive circuit, and 45 is a magnetic head pressing mechanism. Reference numeral 46 denotes a higher-level controller that comprehensively controls the entire recording apparatus.

FIG. 2 is a perspective view showing a schematic configuration of a magneto-optical recording apparatus showing one embodiment of the present invention.

In FIG. 2, reference numeral 11 denotes an optical head, which includes a semiconductor laser for emitting light, a collimator lens, an optical sensor, an objective lens 9 for condensing light on a recording medium, and the like. Reference numeral 2 denotes a flying head slider. The slider 2 includes a core 1 and a coil, which are components of a magnetic head.
When the magneto-optical disk 12 is rotated at a predetermined rotation speed or more, the flying head slider 2 obtains a floating force mainly due to the viscosity of air between the slider 2 and the disk 12. The magnetic head core 1 and the objective lens 9 of the optical head 11 are a magneto-optical disk.
They are located opposite each other with 12 in between.

Reference numeral 10 denotes an AE sensor provided in the flying head slider 2. The AE sensor 10 is an element for observing AE (acoustic emission) generated by contact between the information recording medium surface and the magnetic head. This sensor is arranged in a position where the contact sound between the magneto-optical disk 12 and the flying head slider 2 is most easily observed, for example, on the opposite side of the slider surface in contact with the disk, that is, in close contact with the back surface of the head slider. Examples of the AE sensor applicable to this embodiment include FAE-C56 and FAE-C40 manufactured by Fuji Electric Chemical Co., Ltd.

A load spring 4 supports the flying head slider 2 and applies a predetermined force to the flying head slider 2 in a direction perpendicular to the recording medium surface by a mechanism described later. Load spring 4
The flying head slider 2 is fixed to the front end of the head, and the rear end is fixed to the load spring support 20.

In this embodiment, the load spring support 20 is fixedly attached to the end of the optical head 11, and the motor 8 having the eccentric cam 7 is fixed. Also load spring support
A plate spring 6 to which an adjusting coil spring 5 for adjusting the pressing force applied to the flying head slider 2 is fixed to the end of the plate 20 is fixed. The eccentric cam 7 is in contact with the center of the leaf spring 6 (the position of the eccentric cam 7 changes depending on the magnitude of the pressing force applied to the flying head slider 2). Accordingly, the pressing force applied to the load spring 4 increases. With this configuration, the swinging motion of the leaf spring 6 caused by the rotation of the eccentric cam 7 can be changed to a gentle and stable pressing force determined by the elasticity of the adjusting coil spring and the load spring 4. . The flying head slider 2 shown in FIG.
Has a wide rear end and a narrow front end,
This stably changes the pressing force applied to the flying head slider 2, and as a result, the flying head slider 2 and the disk 12
This is for slightly changing the distance from the surface in the X direction.

 FIG. 3 is a schematic block diagram of the embodiment of FIG.

Next, the operation of the present embodiment in the above configuration will be described with reference to the block diagrams of FIGS.

As described above, since the magneto-optical recording medium is portable, dust, dust, and the like adhere to the surface of the medium. Therefore,
When the deposit is caught between the media surfaces of the magnetic head,
Scratches on the medium surface and collision with the flying head occur. The minute sound such as a flaw or a collision is detected by the AE sensor 10 as a signal S1 and amplified by a predetermined number in the amplifier 30 (signal S2). The signal S2 is input to the pressing force controller 32, and it is determined by the characteristics of the adjusting coil spring 5, the load spring 4, and the eccentric cam 7 in accordance with parameters such as the loudness of the sound and the number of revolutions of the disk 12. The pressing force of the head slider 2 is determined by a ROM table 36 or the like prepared in advance, and the signal S
3 is sent to the motor drawer 34. The motor drawer 34 rotates the motor 8 by a predetermined amount, changes the pressing force of the flying head slider 2, and controls the flying amount to a desired value.

[Other Embodiments] In the above embodiments, the flying head slider has been described as an example. However, the present invention is not limited to the flying head slider.
The present invention can also be implemented with a slider configuration designed to move in a contact state implemented in FDD or the like. An example of such a configuration is shown in FIGS. 4 (a) and 4 (b).
4 (a) is a plan view, FIG. 4 (b) is a side view,
50 is a slider, 51 is a gimbal flexure, 52 is a motor for rotating the eccentric cam 53, 54 is an optical head, 55 is a joint leaf spring, 56 is a leaf spring, and 57 is an adjusting coil spring.

The inclination of the slider 50 is self-aligned with respect to the disk via the gimbal flexure 51 by the adjusting coil spring 57, and the slider 50 is biased. By the eccentric cam 53,
The urging force is adjusted by bending the leaf spring 54 and expanding and contracting the adjusting coil spring 57.

In the above-described embodiment, the adjusting coil springs 5, 57 may be compression coil springs.

Further, for a medium in an extremely bad state (frequent occurrence of AE), a signal may be sent to the system (upper controller 38, 46) to transmit a warning sign such as a backup to the user.

FIG. 2 shows an embodiment in which the contact state detecting means is constituted by an element for observing AE (Acoustic Emission) generated by the contact between the information recording medium surface and the magnetic head. If it is possible to know the state of dust, dust and the like substantially generated in the gap, such as a method of detecting the capacitance between the magnetic head and the recording medium, such means can be adopted.

Further, it is apparent that the applicable recording medium is not limited to the magneto-optical recording medium in terms of controlling the gap between the magnetic head and the recording medium.

[Effects of the Invention] As described above in detail, according to the magnetic recording apparatus of the present invention, since the contact state between the magnetic head and the recording medium can be constantly controlled, the degree of damage and destruction of the medium surface by the magnetic head can be reduced. And media life can be extended.

Further, according to the present invention, since the influence of dust, dust, and the like can be reduced, there is an effect that the reliability of information recording is improved.

When the present invention is applied to a magneto-optical recording device, the magnetic pole approaches the recording medium surface, and overwriting by magnetic field modulation is enabled. Accordingly, a magneto-optical recording device capable of high-speed information processing is provided.

In addition, it is also possible to adopt a configuration in which a warning sign is issued to the user before the medium surface is destroyed by the contact of the magnetic head, and the system is highly applicable.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram of a magneto-optical recording apparatus according to the present invention. FIG. 2 is a schematic configuration diagram of a magneto-optical recording apparatus showing one embodiment of the present invention. FIG. 3 is a schematic block diagram of the embodiment of FIG. FIGS. 4A and 4B are diagrams for explaining another embodiment of the present invention. 40: contact state detection sensor, 41: amplifier, 42: controller, 43: storage means, 44: pressing mechanism drive circuit, 45: magnetic head pressing mechanism, 46: host controller, 1: magnetic head core, 2: flying head slider, 4: Load spring, 5: Adjusting coil spring, 6: Leaf spring, 7: Eccentric cam, 9: Objective lens, 12: Magneto-optical disk.

Claims (3)

(57) [Claims] 1. A contact state detecting means for detecting a contact state between a surface of an information recording medium and a magnetic head and generating a detection signal, a pressing means for pressing the magnetic head in a direction substantially perpendicular to the information medium surface, Storage means for storing the magnitude of the detection signal and the pressing force of the pressing means determined by the characteristics of the pressing means, and control means for controlling the pressing force according to the detection signal and the contents stored in the storage means. , Wherein the pressing means includes an adjusting coil spring. 2. The device according to claim 1, wherein said contact state detecting means comprises an element for observing an AE (acoustic emission) caused by a contact between said information recording medium surface and said magnetic head. Magnetic recording device. 3. The magnetic recording apparatus according to claim 1, wherein the recording medium is a magneto-optical recording medium, and the magnetic head is a magnetic head employing a so-called magnetic field modulation system.