JPH08339585A - Magnetic head for magneto-optical recording - Google Patents

Abstract

PURPOSE: To obtain a magnetic head for magneto-optical recording with which working and assembling stages are greatly simplified, the cost is reduced, a high-speed signal recording is made possible and the wear and damage of recording media are lessened by constituting a slider of a resin material and embedding and molding cores, coils and radiating members therein. CONSTITUTION: The cores 2 and the coils 3 are mounted in the slider 1 on which formed with opposed surfaces floating or sliding opposing to a magneto- optical recording medium. A modulated bias magnetic field is impressed on the magneto-optical recording medium by supplying a current to the coils 3 and the magnetic head for magneto-optical recording, is driven. The slider 1 is composed of a resin material. The cores 2, the coils 3 and the radiating members 4a, 4b consisting of a material having a high thermal conductivity are molded in the state of embedding these members into the slider. The slider 1 may, otherwise, be formed out of a resin material into which fillers consisting of a material having a high thermal conductivity are incorporated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention uses a magnetic field modulation system to
The present invention relates to a magneto-optical recording magnetic head for recording an information signal on a magneto-optical recording medium.

[0002]

2. Description of the Related Art As a magneto-optical recording device for recording information at a high density on a magneto-optical recording medium such as a magneto-optical disk, a magneto-optical recording system is known. In this method, laser light is converged through an objective lens and irradiated onto a recording medium to form a light spot with a diameter of about 1 μm, and
On the other hand, the information signal is recorded by applying a magnetic field, which is modulated by the given information signal, to the laser light irradiation site by the magnetic head.

Such a generally known magneto-optical recording apparatus of the magnetic field modulation type has a structure as shown in FIG. 8, and the magneto-optical recording medium 21 used here is a disk shape. The structure has a signal recording layer formed on a transparent substrate. The disk 21 is rotationally driven by a spindle motor 22. At this time, a floating magnetic head 23 is provided on the upper surface side of the disk 21, and a lower surface side is provided with the floating magnetic head 23.
The optical heads 24 are arranged so as to face the magnetic head 23 and face each other.

The magnetic head 23 includes the suspension 2
The optical head 24 and the fixed end of the suspension 25 are connected to each other by a connecting member 26 to form a magneto-optical unit. The connecting member 26 is attached to the linear motor 27,
Therefore, by driving the linear motor 27, the optical head 24 and the magnetic head 23 are integrated, and the disk 2
1 is configured to be transferred in the radial direction.

In this magnetic field modulation type magneto-optical recording apparatus, when an information signal is recorded on the disk 21, a laser beam is emitted from the optical head 24 while the disk 21 is rotated at a high speed by the spindle motor 22. 28 is irradiated onto the signal recording layer of the disk 21 to form an image as a light spot having a diameter of about 1 μm. As a result, the temperature of the signal recording layer at the irradiated portion rises above the Curie temperature.
At the same time, the magnetic head 23 applies a bias magnetic field, which is modulated according to the applied information signal, to the temperature-rising portion. As a result, the direction of magnetization of the signal recording layer faces the direction of the bias magnetic field, and the information signal is recorded on the signal recording layer.

A magnetic head for magneto-optical recording used in such a magneto-optical recording apparatus has a structure as shown in FIG. 6B is an overall perspective view of the magnetic head, and FIG. 6A is an enlarged view of the core thereof. here,
Reference numeral 12 denotes a core, which is generally made of ferrite having high magnetic permeability. Reference numeral 13 is a coil wound around the main magnetic pole of the core 12.

This magnetic head has a slider 11 for flying above the disk or traveling in sliding contact with the disk, which is made of a non-magnetic ceramic such as CaTiO _3. There is. The core 12 and the slider 11 are fused by the glass 14.

In manufacturing such a magnetic head, first, the slider 11 and the core 12 are manufactured by machining, then these are fused by the glass 14, and then the coil 13 is attached to the main magnetic pole of the core 12. Roll and assemble.

[0009]

FIG. 7 is a graph showing the relationship between the recording current flowing through the coil of the conventional magnetic head for magneto-optical recording and the magnetic field generated by the magnetic head. Generally, in order to perform signal recording on the magneto-optical disk in good condition, it is necessary to apply a bias magnetic field of 200 to 300 Oe. According to this graph, when the recording current is small, the generated magnetic field is proportional to the recording current. However, as the recording current increases, the generated magnetic field eventually becomes saturated. This is because the magnetic flux density inside the core cannot increase beyond the saturation magnetic flux density of ferrite.

Moreover, the magnitude of the saturation magnetic field depends on the frequency f of the recording signal as shown in the drawing, and the saturation magnetic field tends to decrease as the frequency f increases. This phenomenon occurs when the frequency f of the recording signal is higher, the magnetic head (especially,
This is because the high frequency loss in the core and the coil increases, and the magnetic head generates heat, and the saturation magnetic flux density of the ferrite forming the core is reduced accordingly.

In recent years, in such a magneto-optical recording device, there is a strong demand for high speed signal recording.
In order to satisfy this, it is necessary to increase the frequency of the recording signal. However, as described above, when the frequency of the recording signal is increased, the magnetic head generates heat, and the saturation magnetic field is reduced. For example, as shown in FIG. 7, the frequency of the recording signal is set to 10 MHz or higher. However, no matter how much the recording current is increased,
It is not possible to obtain a generated magnetic field of 00 Oe or more. As described above, the frequency of the recording signal is limited by the capability of the magnetic head, so that there is a problem that the signal recording cannot be performed at a desired high speed.

Further, the applicant of the present application has previously filed Japanese Patent Application Laid-Open No. 3-29.
As disclosed in Japanese Patent No. 5080, a magnetic head using a thermosetting resin material, a thermoplastic resin material, or a photocurable resin material provided with wear resistance and lubricity has been proposed as a material of a slider. According to this, when the magneto-optical recording medium and the magnetic head are in sliding contact with each other, it is possible to prevent the magnetic head and the magneto-optical recording medium from being worn and damaged.

On the other hand, the resin material used for the above slider is the above-mentioned ceramic material [CaTi].
The thermal conductivity is still worse than that of O ₃ ], so that the heat dissipation characteristic of the magnetic head is poor, and the above-mentioned problem that signal recording cannot be performed at a sufficiently high speed is made more serious.

[0014]

The present invention has been made based on the above circumstances, and is directed to a slider having a facing surface that floats or slides facing a magneto-optical recording medium. In a magnetic head for magneto-optical recording, which comprises a core and a coil, supplies a current to the coil, and applies a modulated bias magnetic field to the magneto-optical recording medium, the slider is made of a resin material, In addition, the core, the coil, and the heat dissipation member made of a material having high thermal conductivity are embedded and molded.

Further, in the present invention, a core and a coil are mounted on a slider having a facing surface that floats or slides facing the magneto-optical recording medium, and a current is supplied to the coil. In the magneto-optical recording magnetic head for applying a modulated bias magnetic field to the magneto-optical recording medium, the slider is made of a resin material containing a filler made of a material having high thermal conductivity, and It is molded with the core and the coil embedded.

[0016]

As a result, the problems in the prior art are solved, and signal recording can be performed at high speed. In addition to that, the effect of preventing abrasion damage of the magneto-optical recording medium can be obtained as in the magnetic head previously proposed by the applicant of the present application. Furthermore, in the magnetic head according to the present invention, the slider is made of a resin material, and the core, the coil, and the heat dissipation member are embedded and molded. It is simplified and can be manufactured at a very low cost.

[0017]

【Example】

(First Embodiment) An embodiment of the magnetic head for magneto-optical recording according to the present invention will be specifically described below with reference to the drawings.
1A, 1B, and 1C respectively show a magnetic head,
It is the figure seen from the upper surface, the side surface, and the bottom surface. Here, reference numeral 1 is a slider, which is made of a resin material such as a thermosetting resin material, a thermoplastic resin material, or a photocurable resin material. In addition, on the bottom surface side of the slider 1, facing surfaces 1a and 1b which are floated or slid facing the magneto-optical recording medium.
Is formed. In particular, the slider 1 is molded with the core 2, the coil 3, and the heat dissipation member 4a embedded therein.

FIG. 4 shows the structure of the core 2 and the coil 3 in detail. The core 2 is made of a magnetic material having a high magnetic permeability such as ferrite. In this embodiment, the core 2 has a rectangular plate shape, and the magnetic pole 2a is provided so as to project in the center thereof. The tip of the magnetic pole 2a is exposed on the surface of the facing surface 1b, and the coil 3 is provided around the magnetic pole 2a. By supplying a current to the coil 3, a magnetic flux extends from the tip of the magnetic pole 2a toward the magneto-optical recording medium,
A bias magnetic field is applied to the magneto-optical recording medium. A heat radiating member 4a made of a material having high thermal conductivity, for example, a metal material such as aluminum or copper or a ceramic material such as AlN or SiC is provided on the core 2. Here, the heat dissipation member 4a
Acts to effectively dissipate the heat generated in the core 2 and the coil 3 when the frequency of the recording signal is increased.
Therefore, the temperature rise of the core 2 is suppressed, and as a result,
The saturation magnetic field does not decrease even if the frequency of the recording signal is made higher than in the conventional case.

In particular, as shown in the figure, the heat dissipation effect can be enhanced by providing the lower part of the heat dissipation member 4a in close contact with the core 2 and the upper part exposed on the upper surface of the slider 1. Further, if necessary, the heat dissipation effect can be further enhanced by forming the exposed portion of the heat dissipation member 4a into a corrugated shape such that the surface area thereof becomes large as shown in the drawing.

The thermal conductivity of the material forming the heat radiating member 4a is about 0, which is the thermal conductivity of the ceramic (eg CaTiO ₃ ) forming the slider of the conventional magnetic head.
Greater than 02cal / cm · sec · ° C and 0.1c
It is desirable that the temperature is equal to or higher than al / cm · sec · ° C. Typical examples thereof include metal materials such as aluminum and copper and ceramic materials such as AlN and SiC.

FIG. 5 is a graph showing the relationship between the recording current flowing through the coil and the magnetic field generated by the magnetic head in the magnetic head according to the present invention. According to this, even when the frequency of the recording signal is 14 MHz, the saturation magnetic field is
It exceeds 200 Oe required for good signal recording, and it is understood that signal recording can be performed at a speed sufficiently higher than in the past.

Further, the slider 1 is constructed by embedding the core 2, the coil 3 and the heat dissipation member 4 and molding a resin material. Therefore, glass in the resin material,
It is also easy to add wear resistance to the slider 1 by incorporating particles made of carbon or a ceramic material such as Al ₂ O ₃ , SiN, BN, and TiO ₂ .

It is also easy to prevent the abrasion damage of the slider and the magneto-optical recording medium by adding a lubricant such as Teflon, polytetrafluoroethylene or MoS ₂ to the resin material to impart lubricity. is there.

Further, in the conventional manufacturing of a magnetic head, a slider is formed by machining a brittle material such as ceramic and the core and the coil are sequentially assembled. In contrast to this, the magnetic head of the present invention is used. Then, since the slider is integrally formed by molding the resin material and further embedding the core 2, the coil 3, and the heat dissipation member 4a, the processing and assembling steps are greatly simplified, which makes it extremely possible. It can be manufactured at low cost. In the present invention, a compression molding method, an injection compression molding method, or the like can be used for molding the slider. (Second Embodiment) FIG. 2 shows the structure of a magneto-optical recording magnetic head according to a second embodiment of the present invention. 2A, 2B, and 2C are views seen from the top, side, and bottom, respectively. In addition, here, the first embodiment
The same parts in FIG. 1 indicating the same are assigned the same reference numerals and detailed description thereof will be omitted.

Also in this embodiment, the slider 1 is made of a resin material and is molded with the core 2, the coil 3 and the heat radiation material 4b embedded therein. The radiating member 4b is provided below the coil 2. In particular, as shown in the figure, since the upper part of the heat dissipation member 4b is provided in close contact with the coil 3 and the lower part is exposed to the facing surface 1b of the slider 1, the heat dissipation effect can be enhanced.

When the magnetic head flies over the disk, air flows at high speed toward the facing surfaces 1a, 1b of the slider, so that the effect of exposing the heat dissipation member 4b to the facing surface 1b becomes greater. (Third Embodiment) FIG. 3 shows the structure of a magnetic head for magneto-optical recording according to a third embodiment of the present invention. 3A, 3B, and 3C are views seen from the top, side, and bottom, respectively. In addition, here, the first embodiment
The same parts in FIG. 1 indicating the same are assigned the same reference numerals and detailed description thereof will be omitted.

In this embodiment, the slider 1 is made of a material having high thermal conductivity, such as a metal material such as aluminum or copper, or A.
It is made of a resin material such as a thermosetting resin material, a thermoplastic resin material, or a photocurable resin material containing a filler 5 made of a powder of ceramic material such as 1N or SiC, flakes, or fibers. Also, the slider 1 is the core 2
And the coil 3 is embedded.

The filler 5 serves to enhance the thermal conductivity of the slider 1 and effectively dissipate the heat generated in the core 2 and the coil 3 when the frequency of the recording signal 3 is increased. Therefore, the temperature rise of the core 2 is suppressed, and as a result, the saturation magnetic field does not decrease even if the frequency of the recording signal is made higher than in the conventional case.

The filler 5 is made of a metal material such as
When the slider 1 is made of a material having a high thermal conductivity and a high electrical conductivity, the electrical conductivity of the slider 1 is enhanced, so that static electricity is not generated even when the slider and the disk come into sliding contact with each other. As a result, it is possible to prevent an adverse effect caused by static electricity on the magnetic head, that is, damage to the disk due to electric discharge and adsorption between the magnetic head and the disk.

Further, glass, carbon, or Al together with the filler 5 is contained in the resin material forming the slider 1.
It is also easy to add wear resistance to the slider 1 by incorporating particles made of a ceramic material such as ₂ O ₃ , SiN, BN, and TiO ₂ . Further, it is easy to prevent the abrasion damage of the magneto-optical recording medium by adding a lubricant such as Teflon, polytetrafluoroethylene, NoS ₂ or the like to the resin material to impart lubricity.

Further, since the slider 1 is made of a resin material and is integrally manufactured by embedding the core 2 and the coil 3, the processing and assembling steps are greatly simplified, which results in extremely low processing. It can be manufactured at a cost.

[0032]

As described above, according to the present invention,
The following effects can be obtained. (1) Since the slider is made of a resin material and the heat dissipation member made of a material having high thermal conductivity is provided, it becomes possible to perform signal recording at high speed. (2) Since the slider is made of a resin material containing a filler made of a material having high thermal conductivity, signal recording can be performed at high speed. (3) In addition to the above effects, if the slider is made of a resin material containing particles made of a ceramic material, abrasion and damage of the slider can be prevented. (4) In addition to the above effects, if the slider is made of a resin material containing a lubricant, abrasion and damage of the slider and the magneto-optical recording medium can be prevented. (5) If the slider is made of a resin material containing a filler having a high thermal conductivity and a high electrical conductivity,
It is also possible to prevent the generation of static electricity. (6) The slider is made of resin material, and the core, coil,
It is possible to manufacture at low cost by molding the heat dissipation member in a buried state.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a first embodiment of a magnetic head for magneto-optical recording according to the present invention.

FIG. 2 is a diagram illustrating a second embodiment of the magneto-optical recording magnetic head according to the present invention.

FIG. 3 is a diagram illustrating a third embodiment of the magneto-optical recording magnetic head according to the present invention.

FIG. 4 is a core of a magnetic head for magneto-optical recording according to the present invention;
It is a figure which shows the structure of a coil.

FIG. 5 is a graph showing the relationship between the recording current and the generated magnetic field of the magneto-optical recording magnetic head according to the present invention.

FIG. 6 is a diagram showing a configuration of a conventional magnetic head for magneto-optical recording.

FIG. 7 is a graph showing a relationship between a recording current and a generated magnetic field of a conventional magneto-optical recording magnetic head.

FIG. 8 is a diagram showing a schematic configuration of a magneto-optical recording device.

[Explanation of symbols]

 1 slider 2 core 3 coil 4a, 4b heat dissipation member 5 filler

Claims (7)

[Claims] 1. A slider having a facing surface that floats or slides facing a magneto-optical recording medium,
In a magneto-optical recording magnetic head having a core and a coil mounted thereon, supplying a current to the coil to apply a modulated bias magnetic field to the magneto-optical recording medium, the slider is made of a resin material, and A magnetic head for magneto-optical recording, wherein the core, the coil, and the heat dissipation member made of a material having high thermal conductivity are molded in a buried state. 2. The magnetic head for magneto-optical recording according to claim 1, wherein the heat dissipation member is made of a metal material or a ceramic material. 3. The magnetic head for magneto-optical recording according to claim 1, wherein a part of the heat dissipation member is provided in close contact with the core or the coil. 4. The magnetic head for magneto-optical recording according to claim 1, wherein a part of the heat dissipation member is provided so as to be exposed on the side opposite to the air bearing surface of the slider. 5. A slider having a facing surface that floats or slides facing a magneto-optical recording medium,
In a magneto-optical recording magnetic head having a core and a coil mounted thereon, supplying a current to the coil to apply a modulated bias magnetic field to the magneto-optical recording medium, the slider is made of a material having high thermal conductivity. A magnetic head for magneto-optical recording, which is formed of a resin material containing a filler, and is molded with the core and the coil embedded therein. 6. The magnetic head for magneto-optical recording according to claim 5, wherein the filler is a metal material. 7. An optical head that converges and irradiates light on a magneto-optical recording medium, and a magnetic head for magneto-optical recording that applies a bias magnetic field modulated by a given information signal to a light irradiation portion. In the magneto-optical recording device provided, the magneto-optical recording magnetic head has the structure according to any one of claims 1 to 6.