JPS62204412A - Magnetic head - Google Patents

Abstract

PURPOSE:To obtain a floppy head without necessitating an erasing head and capable of recording on a high-coercive force medium with high precision by composing the first core half of the titled head out of the first high-permeability alloy film, a nonmagnetic film of SiO, etc., and the second high-permeability alloy film, and bonding the second core half to the second high-permeability alloy film. CONSTITUTION:A high-permeability alloy film 4 of 'Sendust(R)', an amorphous alloy, etc., is formed by sputtering, etc., in about 10mum thickness on the first core half 1 obtained by bonding a soft magnetic ferrite core 24 of ferrite, etc., and a 'Sendust(R)' core 25 through an adhesive layer 26, and then a nonmagnetic film 5 of SiO2, etc., is deposited in 0.5mum thickness to form a high-permeability alloy film 6 having about 10mum thickness. Subsequently, the second core half 2 having a composition similar to that of the first core half 1 is bonded by lead glass 3 to constitute a head. The head thus formed is provided with a track width TW3 positioned in the core and a track width TW4 on the region inclined at an angle of theta to both surfaces, and the track width of the head becomes TW5.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention enables effective recording and reproduction of high coercive force recording bodies.
The present invention also relates to a new high-output magnetic head such as a floppy head that does not require an erase head.

BACKGROUND OF THE INVENTION FIG. 4 shows the medium sliding surface of a conventional floppy head. This head has a core half made of ferrite 8
and a read/write head having a read/write gap (referred to as R/W gap) formed by voiding the core half body 9 with glass 10, and the core half bodies 13 and 1.
An erase head having an erase gap 16 formed by bonding 4 and 4 with glass 16 is joined via a non-magnetic block.

Further, FIG. 5 shows the locus of the magnetization pattern recorded on the recording medium. Initially, the width of the pattern recorded in the R/W gap is the track width TW1 of the R/W head, and then the erase head is excited by a DC current to be erased by the track width TW2 of the erase head, and the final pattern is recorded. A final pattern 18 with a width of TW3 is left behind.

By regulating the track width as described above, a no-signal band with a width of TW2 is secured on both sides of TW3 when writing on a pre-recorded medium, and when reproducing a signal, the head track is with a width of TWa. TW2 even if it is off the signal band
Because there is a no-signal band with a width of

As the wavelength of the signal becomes shorter on a disc-shaped medium such as a floppy disk, the distance between the R/W gap 12 and the erase knob 15 must be made smaller in order to perform the above series of recording and erasing operations with high accuracy. It is extremely important to do so.

Problems to be Solved by the Invention However, the current state of the art is that the structure of the conventional head has mechanical limitations, and at the same time, the R/W head and the erase head have two different functions. This has the problem of requiring complicated steps to manufacture the head, such as joining the head together.

In view of these problems, the present invention provides a magnetic head having a novel structure and high S/N.

Means for Solving the Problems In order to achieve the above object, the present invention comprises a pair of composite cores of high magnetic permeability alloy and ferrite, and a first high magnetic permeability core half formed on the first core half. an alloy film, a non-magnetic film such as a SiO2 film formed on the first high magnetic permeability alloy film,
a second high magnetic permeability alloy film formed on the non-magnetic film;
It has a structure in which a second high magnetic permeability alloy film and a second core half are joined.

Operation The present invention provides a high-performance magnetic head with the above-described configuration, which does not require an erase head, has good accuracy, and uses a composite core half made of sendust and ferrite.

Embodiment FIG. 1 shows the structure of the magnetic head of the present invention, and FIG. 2 shows the sliding surface of the medium.

In FIG. 1, a high magnetic permeability alloy film 4 such as sendust or amorphous alloy is sputtered on a first core half 1 in which a soft magnetic ferrite core 24 such as ferrite and a sendust core 26 are bonded via an adhesive layer 28. After forming a film with a thickness of approximately 10 μm using a method such as the above, a non-magnetic film 5 such as SiO2 is deposited to a thickness of 6 μm, and a high magnetic permeability alloy film 6 is deposited again.
was formed to a thickness of about 10 μm. Thereafter, a second core half 2 having the same configuration as the first core half is joined to form a lead-based glass 3.
It is constructed by bonding.

The head formed as described above has a track width TW3 located in the core and a track width TW4 in an area inclined by an angle θ on both sides thereof. Therefore, the track width of the head is TW5. By passing a current through the winding 21 wound around the winding window 7 of this head to excite it,
FIG. 3 shows a recording pattern in which signals are written on a recording medium.

As shown in FIG. 3, even if the recording track 22 overlaps with the adjacent track 23, since the azimuth angle θ is set between the recording signals of the adjacent track 23 and the recording track 22, the signal from the adjacent track 23 will not overlap during playback. It is possible to significantly reduce the In addition, there is no need for an erasing head, which is similar to the head described in the conventional example (R/W).
Since alignment accuracy is not required when bonding the rack and erase track, the head has extremely good dimensional accuracy.

In addition, when Sendust is used as the high magnetic permeability alloy film, the softening point of the lead-based glass as the glass 3 is 6oO to 80o.
Bonding is possible if a material with a temperature of 0° C. is used, and in the case of an amorphous alloy, a lead-based glass whose softening point is about 80° C. or lower, which is the crystallization temperature of the amorphous alloy film, may be used. For example, the crystallization temperature of an amorphous Go-Wb-Zr alloy varies depending on the composition amount, but it is 560
℃, and lead glass with a softening point of 460 ℃ was used as the glass.

The saturation magnetic flux density Bs of the high magnetic permeability alloy film used in this head is 9000 [1LuS1i!] by Sendust. .

Co-Nb-zr has a Q value of 8000 to 9000 g&uSg, which is about twice the value of 4500 gauss for ferrite. Therefore, high coercive force media such as metal media (Ha: 120
It has the advantage of being able to sufficiently record even 0 to 1500 oe).

Further, a gap is formed on the first core half 1 by sputtering. Therefore, high precision in joining the second core half 2 is not required, making it difficult to manufacture the TV head.
It depends only on the accuracy of s.

Therefore, a head with higher precision than conventional heads can be obtained.

On the other hand, the sendust core 26 is sandwiched between the ferrite cores 24 from both sides, thereby making it possible to significantly reduce the eddy current loss generated in the sendust core 26 during signal reproduction.

As described above, the present invention provides a floppy head that does not require an erase head and is capable of recording on high precision and high coercive force media.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the structure of the magnetic head of the present invention, and FIG.
The figure is a configuration diagram of the magnetic head of the present invention as seen from the medium sliding surface.
Figure 3 is a pattern diagram when recording on an adult body using the head of the present invention, Figure 4 is a configuration diagram of a conventional head viewed from the media sliding surface, and Figure 5 is a pattern diagram when recording on an adult body using a conventional head. It is a diagram. 1...First core half, 2...Second core half, 4...High magnetic permeability alloy film, 5...
...Nonmagnetic film, 6...High magnetic permeability alloy film, 24.
... Ferrite core, 26 ... Sendust core, 26 ... Adhesive layer. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 3 Figure 4

Claims (1)

[Claims] It is composed of a pair of composite cores made of high magnetic permeability alloy and ferrite, and has a first surface consisting of a gold layer core of the first core half, and a first surface on both sides of this first surface. On the other hand, a first film made of a high magnetic permeability material is tilted at a predetermined angle or more and is formed on a second surface made of ferrite, and a non-magnetic film such as SiO_2 formed on the first film; A magnetic head comprising: a second film made of a high magnetic permeability material formed on the non-magnetic film, and the second film and a second core half are bonded to each other.