JPH0822604A - Magnetic head - Google Patents

Abstract

PURPOSE:To provide a light magnetic head with a simple structure. CONSTITUTION:The magnetic head 1 is constituted of a front core part 4 holding a read/write core 2 provided with an operation gap 8 from its side direction by a slide member 3 to be formed and a back core part 7 provided on the rear side of the front core part and wound with a coil 5. The back core part 7 is provided with comb-shaped core supporters 10 for magnetic circuit formed by grooving machining and holding core supporters on their both sides. Bobbins 6 wound with the coils are loaded on the core supporters for magnetic circuit, and the front core part is joined with the back core part in the state. At this time, the tips of the core supporters are abutted on the back surface of the read/write core, and the tips of the holding core supporters are abutted on the rear sides of the slide members of the front core part 4 to support and fix the side parts of the bobbins. Thus, the manufacture is simplified, and the whole magnetic head is lightened, and the followup ability at a tracking time is improved even when the wobbling of surface of a recording medium is enlarged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head, and in particular, coating, printing, spattering, coating on a part of an optical disk such as a CD (compact disk) or a CD-ROM disk.
Alternatively, the present invention relates to a magnetic head used for recording / reproducing information on / from a magnetic surface formed by means such as attachment of a flexible disk.

[0002]

2. Description of the Related Art Generally, a magnetic surface is provided on a part of an optical disk such as a CD or a CD-ROM disk, and information is recorded on or from this magnetic surface separately from the optical recording area of the disk body. Recording media adapted for reproduction are disclosed in JP-A-53-47802 and JP-A-53-11.
7402, JP-A-56-163536 and JP-B-5-44727.

[0003]

By the way, the above-mentioned C
D and CD-ROM discs, unlike ordinary magnetic discs that are generally used, have a large amount of surface deviation, for example, about ± 0.5 mm. In order to perform stable recording / reproducing even with such a large surface deviation, it is necessary to make the magnetic head stably follow the track of the magnetic surface and make sliding contact therewith.
The conventional magnetic heads disclosed in Japanese Patent Laid-Open No. 2 and Japanese Patent Application Laid-Open No. 53-117402 have a core portion having, for example, a laminated core structure, so that the overall weight becomes relatively heavy, and quick follow-up, that is, appropriateness. There was a problem that it could not be tracked properly.

Further, since the core portion has a laminated structure as described above, the assembly thereof is not only complicated, but also the mounting portion of the gimbal spring is difficult to provide flatness, so that the mounting accuracy of the gimbal spring is inferior. there were. Furthermore,
When the core portion has a laminated structure, there is also a problem that the S / N ratio is slightly inferior.

Further, in the magnetic head disclosed in Japanese Patent Publication No. 5-44727, a large number of columns are provided in a rear core portion joined to a front magnetic head core portion, and a winding is wound on a part of the columns. A bobbin is applied to form a magnetic circuit with the head core portion, and the other pillars support the head core portion.

However, since this magnetic head has two working gaps for reading and writing, many columns must be provided, and the structure becomes complicated and processing becomes very difficult. Furthermore, since the bobbin has a structure in which the support is simply inserted through the center hole of the bobbin, the mounting state becomes relatively unstable, and there is a problem in that, for example, rolling occurs during driving. .

Further, as a related magnetic head structure, as shown in Japanese Patent Application Laid-Open No. 50-87622, a structure in which a front magnetic core and a rear magnetic core are butted against each other is simplified, or JP-B-61-51325. Gazette and Japanese Patent Publication Sho 61-5
Although a multi-element magnetic head structure has been proposed as shown in Japanese Patent No. 8885, none of them solves the above problems.

The present invention focuses on the above problems,
The present invention was devised to effectively solve this problem, and its purpose is to provide a magnetic head having a light weight and a simple structure.

[0009]

In order to solve the above problems, the present invention provides a front core portion formed by holding a read / write core having an operating gap by a sliding member in the side direction. In a magnetic head comprising a back core portion provided on the back side of the front core portion and having a coil wound around it, the back core portion is entirely made of a magnetic material and is formed by grooving.
The magnetic circuit core strut has at its edge a magnetic circuit core strut whose tip contacts the read / write core to form a magnetic circuit, and a holding core strut whose tip contacts the sliding member. A bobbin around which the coil is wound is attached to the holding core strut, and the holding core column supports the front core portion and side portions of the bobbin.

[0010]

Since the present invention is configured as described above, the bobbin around which the coil is wound is mounted on the magnetic circuit core support of the back core portion, and the back core portion and the front core portion are joined together. Then, the tip of the core post for the magnetic circuit of the back core part contacts the read / write core of the front core part to form a magnetic circuit, and the tip of the holding core post is on the back surface of the sliding member of the front core part. It abuts and supports it, and also supports the side part of the bobbin to stably fix it.
The back core portion can be easily manufactured by grooving and can be made lighter, so that the head itself can be made lighter than the conventional laminated core.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a magnetic head according to the present invention will be described in detail below with reference to the accompanying drawings. 1 is an assembly view showing a magnetic head according to the present invention, FIG. 2 is a schematic sectional view taken along the extending direction of a read / write core of the magnetic head shown in FIG. 1, and FIG. 3 is a read of the magnetic head shown in FIG. -A schematic cross-sectional view taken along a direction orthogonal to the extending direction of the light core.

As shown in the figure, the magnetic head 1 is mainly composed of a front core portion 4 having a read / write core 2 and a sliding member 3 and a back core portion 7 for mounting a bobbin 6 around which a coil 5 is wound. Is configured.

Specifically, the read / write core 2 of the front core portion 4 is divided into two in the longitudinal direction, and an operation gap 8 for recording / reproducing information is formed in the central portion. This operation gap 8 has an overwrite function for reading and writing. The sliding member 3
Are provided, for example, as a pair made of a non-magnetic material such as calcium titanate, and the read / write core 2 is sandwiched and bonded from the side direction.

In the front core portion 4 to which the pair of sliding members 3 are adhered, the medium sliding contact surface (upper surface in FIG. 1) facing the recording surface of the recording medium and the rear surface thereof, that is, the core support mounting surface 4A are parallel planes. Processed into a shape. The mounting surface 4A is finished with a very high degree of flatness, and the gimbal spring 14 as a head holding member, which is mounted here as described later, is mounted with high precision.

On the other hand, the back core portion 7 to be joined to the back surface side of the front core portion 4 is entirely made of a magnetic material such as ferrite, which is a flat back core substrate 9 and The pair of magnetic circuit core struts 10 and 10 erected further and the two to four holding core struts 11, 11, 12 and 12 provided on both sides of the struts.
It is mainly composed of and.

The two magnetic circuit core columns 10 and 10
The distance between the upper and lower ends of each column, that is, the core contact surface 10A
The spacing is set so as to be able to come into contact with the respective back surfaces of the divided read / write cores 2, and the holding core columns 11 and 1 are provided.
The positions of 1, 12, and 12 are arranged so that the upper ends of the columns, that is, the core contact surfaces 11A, 11A, 12A, and 12A abut the back surfaces of the corresponding sliding members 3 and 3, respectively. In addition, each core strut 10, 11, 12 is located at the edge of the back core portion 7. To form such a back core portion 7, for example, a rectangular parallelepiped block made of a magnetic material such as ferrite is grooved in directions substantially orthogonal to each other when viewed from the medium sliding surface side, and processed into a comb tooth shape. To be formed. In this case, the grooving direction is substantially the medium traveling direction and the direction substantially orthogonal thereto.

The bobbin 6, 6 on which the coil 5 is wound is mounted on the two magnetic circuit core support columns 10 and 10 located in the center by inserting the insertion holes into the support column 10. . In this case, the bobbins 6 and 6 are bonded and fixed to the column 10 with an adhesive or the like.

With the bobbins 6, 6 attached,
The back surface of the front core part 4 and each core pillar 10, 11, 12
The front core portion 4 and the buffer core portion 7 are joined or fitted by joining the upper end of the. As a result, a closed-loop magnetic circuit composed of the read / write core 2, the magnetic circuit core columns 10 and 10 and the back core substrate 9 is formed, and each sliding member 3 is supported by the supporting core columns 11 and 12.
Will be supported by. Further, the radius between the magnetic circuit core support columns 10 and 10 and the holding core support columns 11 and 12 adjacent to both sides of the magnetic circuit core support columns 10 and 10 is set to be substantially the same as or slightly larger than the radius of the bobbin 6. At the time of mounting, this side portion is supported and fixed by the support core columns 11 and 12.

In this case, the cross-sectional areas of the magnetic circuit core struts 10 and 10, which are the core struts in the central portion, are made different from the cross-sectional area of the joint portion of the back portion of the read / write core 2 to which the tips are joined. For example, it is set slightly larger. According to this, even if a positional deviation occurs due to an adhesion error in the lateral direction of the drawing or the vertical direction of the drawing at the time of joining, this positional deviation can be absorbed and magnetic resistance does not increase.

When the front core portion 4 and the back core portion 7 are joined in this manner, the whole of the front core portion 4 is reinforced with a resin (not shown), and then the medium of the front core portion 4 is slid to obtain a predetermined gap depth. The contact surface is mirror-polished, and further, the entire outer peripheral portion of the medium sliding contact surface including the read / write core 2, that is, the edge portion in sliding contact with the recording medium D (see FIG. 2) is processed into a round shape with a polishing tape or the like. Then, chamfering is performed to form a rounded taper surface T.

When the magnetic head 1 is completed in this way, the gimbal spring 14 is adhered and fixed to the flat back surface side of the front core portion 4 with, for example, an adhesive, and the gimbal spring 14 is attached to an arm (not shown).

Next, the operation of this embodiment constructed as described above will be described. In the magnetic head 1 configured as described above, the medium sliding contact surface of the front core portion 4 is arranged so as to face the recording surface of the disk D, and by rotating the disk D at high speed, Due to the action of the rounded taper surface T formed on the outer peripheral edge, air flows between the recording surface of the disk and the medium sliding contact surface, and the magnetic disk slightly slides.

When recording, a signal current is passed through the coil 5 of the bobbin 6 to change the magnetic flux in the working gap 8 of the read / write core 2 and the signal is stored on the disk recording surface. The change in the magnetic flux of the coil 5 causes a change in the magnetic flux in the working gap 8.
A signal current is induced in.

When the back core portion 7 is formed, such a magnetic head 1 is formed by, for example, grooving a block made of ferrite, unlike the laminated structure of the conventional device. The back core portion 7 can be made lighter than the conventional laminated core structure. Therefore, the magnetic head itself can be made lighter by that amount, and the followability at the time of tracking is improved even for a recording medium having a relatively large surface deviation such as a magnetic recording surface formed on a part of a CD-ROM disk. can do. In particular, in this embodiment, since the columns are provided at the edge of the back core portion 7, the supporting area for the front core portion is increased, and the surface wobbling suppressing effect of the disk can be improved accordingly.

To mount the bobbin 6 around which the coil 5 is wound, it suffices to insert the bobbin 6 through the magnetic circuit core stanchions 10 and 10 erected in the central portion of the back core portion 7 and fix them by adhesion. This assembly can be performed stably and quickly. At this time, the magnetic circuit core support 1
The holding core stanchions 11 and 12 located on both sides of 0 and 10 also have a function of supporting the bobbins 6 and 6 from both sides thereof, which also enables stable assembly of the head. Therefore, when the head is driven, the bobbin 6 does not roll laterally, and stable recording / reproducing operations can be performed.
Further, since the holding core column has two functions as described above, it is not necessary to separately provide a bobbin roll preventing column, and the weight can be reduced accordingly.

Furthermore, when the back core portion 7 has a laminated structure as in the conventional structure, a gap is generated on the back surface side of the back core portion 7 when a gimbal spring is bonded and fixed to the back core portion 7, but as described above, the positional deviation occurs. In addition, in this embodiment, since the gimbal spring is attached to the back surface side of the front core portion which is formed flat, the gimbal spring can be adhered and fixed with high accuracy and easily without displacement.

Here, a conventional laminated type magnetic head was prototyped with dimensional specifications matched, and the S / N ratio of the magnetic head of the present invention was compared and examined. In the case of the magnetic head of the present invention, S / It was found that the N ratio can be improved by about 1 to 2 dB.

In the above embodiment, the substantially entire surface of the front core portion 4 is used as the medium sliding contact surface, but the invention is not limited to this. For example, as shown in FIG. 4 and FIG. You may comprise so that it may become. That is, the vicinity of a portion including the operation gap 8 of the read / write core 2 is projected upward to form the first core sliding contact portion 15, and further the two core portions 2 on both sides are formed.
In the two sliding members 3 and 3, the first core sliding contact portion 1
Second core sliding contact portions 16, 16 protruding upward are formed at portions located at both corners of the isosceles with 5 as the apex or the base of the equilateral triangle to form a three-point support structure. And
The peripheral portions of the tips of the first and second projecting core sliding contact portions 15, 16 and 16, that is, the edge portions are processed into a round shape with a polishing tape or the like to form a round taper surface T. The state of the core sliding contact portion at this time is shown in FIG. Further, the back core portion 7 and the bobbin 6 are constructed in the same manner as in the previous embodiment. According to such a configuration, not only the same operational effects as those of the previous embodiment are exhibited, but also a stable sliding contact can be obtained because the sliding contact area with the disk recording surface is reduced.

In the above embodiment, the magnetic head of the present invention is used for a CD or CD-R which partially has a magnetic recording surface.
Although the case of applying to the OM disk has been described, the present invention is not limited to this and can be applied to a normal magnetic disk.

[0030]

As described above, according to the magnetic head of the present invention, the following excellent operational effects can be exhibited. By forming the back core by grooving, it is possible to reduce the weight of the magnetic head itself, and thus to stably follow a disk-shaped recording medium with a large surface deviation of about ± 0.5 mm. Therefore, proper tracking can be performed. In addition, since the holding core column has the function of supporting the front core and the function of holding the bobbin, it is possible to prevent the bobbin from rolling sideways while driving while maintaining a high recording / playback characteristic while reducing the weight. it can. Further, the S / N ratio can be improved as compared with the conventional laminated magnetic head.

[Brief description of drawings]

FIG. 1 is an assembly diagram showing a magnetic head according to the present invention.

FIG. 2 is a schematic cross-sectional view taken along the extension direction of the read / write core of the magnetic head shown in FIG.

3 is a schematic side view as seen from the extending direction of the read / write core of the magnetic head shown in FIG.

FIG. 4 is an assembly diagram showing a magnetic head of a modified example of the invention.

5 is a partially enlarged view of the magnetic head shown in FIG.

[Explanation of symbols]

1 ... Magnetic head, 2 ... Read / write core, 3 ... Sliding member, 4 ... Front core part, 4A ... Core support surface, 5 ...
Coil, 6 ... Bobbin, 7 ... Back core part, 8 ... Operating gap, 9 ... Back core substrate, 10 ... Magnetic circuit core support, 10A ... Core contact surface, 11, 12 ... Holding core support, 11A, 12A ... Core contact surface, 14 ... Gimbal spring (head holding member), D ... Recording medium.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Norio Onori 3-12 Moriya-cho, Kanagawa-ku, Yokohama, Kanagawa Japan Victor Company of Japan, Ltd.

Claims (3)

[Claims] 1. A front core portion formed by holding a read / write core having an operating gap in a lateral direction by a sliding member, and a coil provided on the back side of the front core portion and wound with a coil. A magnetic head composed of a back core portion which is made of a magnetic material and is formed by grooving, the tip of which is in contact with the read / write core to form a magnetic circuit. A core strut and a holding core strut whose tip is in contact with the sliding member are provided only at the edge portions thereof, and a bobbin wound with the coil is attached to the magnetic circuit core strut, Is configured to support the front core portion and side portions of the bobbin. 2. The magnetic head according to claim 1, wherein a head holding member having elasticity is attached to a surface of the front core portion opposite to the operation gap. 3. The area of the core strut mounting surface on the side opposite to the working gap of the front core portion is different from the area of the core contact surface of each core strut.
Alternatively, the magnetic head described in 2.