JPS6316407A - Magnetic head - Google Patents

Abstract

PURPOSE:To avoid deterioration in the reproduction output by securing a round shape at both end parts of a gap in order to prevent the spread of a generated magnetic field. CONSTITUTION:A groove 7 prescribing the signal width 9 encloses a center core 2 and a glass 8 is used to weld a 1st core 1, the core 2 and a 3rd core 3 together for production of a magnetic head. In this welding stage the temperature is kept at a certain level so that the glass viscosity is set at about (5X10<3>) poise with the holding time set at 3hr, for example. Thus a round shape 6 is secured at both ends of a gap respectively. The roundness of the shape 6 can be changed freely by varying the combination of the holding temperature and the holding time of the glass 8. Furthermore, a ferromagnetic field is produced only at the inside of the gap and both end parts of the gap have weak magnetic fields with no concentration of magnetic fluxes owing to the shapes 6. Thus the generated magnetic field has no outward spread.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic head used in a magnetic recording/reproducing device.

[Conventional technology]

The conventional magnetic head was developed by Japanese Patent Application Laid-open No. 57-56425.
As shown in the figure, both ends of the gap were formed at right angles. This is JP-A-57-58221, also JP-A-60.
-226005. The structure of JP-A-57-50316 was also the same.

[Problem that the invention seeks to solve]

However, in the above-mentioned conventional technology, as shown in Figure 4, the magnetic field generated during recording spreads over a large area on the side of the gap, and in particular, due to the expansion of the erase magnetic field, recording is performed in the write-read gap as shown in Figure 5. There is a problem in that when both sides of the signal 90 are erased, the remaining signal 13 has a width smaller than the desired width.

SUMMARY OF THE INVENTION The present invention aims to solve these problems, and its purpose is to provide a magnetic head that has a simple structure, eliminates the reduction in signal width due to the expansion of the erase magnetic field, and prevents a reduction in reproduction output. It is in.

[Failure to solve the problem]

The magnetic head of the present invention has a write/read gap whose desired width is regulated by grooves formed on both side surfaces of a magnetic core in a direction perpendicular to the track direction, and a write/read gap formed at the rear of the write/read gap in the track direction. The magnetic head is characterized in that erasing gaps are formed on both sides of the gap in the track direction and in the vertical direction, wherein both ends of the writing-reading gap and the erasing gap have rounded shapes. do.

[Effect]

According to the above configuration of the present invention, as shown in FIG. 2, when a magnetic field is generated, a strong magnetic field is generated only inside the gap, and the magnetic field is weak at both ends due to the rounded shape, and the magnetic field is not concentrated because the magnetic flux does not concentrate. No spreading to the outside [Embodiment] FIG. 1 is a front view of a sliding surface of a magnetic head according to an embodiment of the present invention. The magnetic core of this example uses Mn-Zn polycrystalline ferrite, and glass has a high working temperature (88
00℃). Grooves 7 regulating the width 9 of the core are provided on both sides of the central core 2, and the first core 1, the grooved central second core 2, and the third core 3 are connected to the glass 8. The magnetic head of this embodiment is constructed by fusing the magnetic head using the following method. In this glass melting layer process, by maintaining the temperature at which the viscosity of the glass is approximately 5 x 10"f Az, and by setting the holding time to, for example, 3 hours, a rounded shape 6 can be provided at both ends of the gap. The shape and size can be changed depending on the combination of the holding temperature and holding time of the glass.

In this embodiment, MnZn polycrystalline ferrite is used for the magnetic core, but other magnetic materials may also be used.

FIG. 6 is a front view of the sliding surface of a magnetic head according to another embodiment of the present invention. According to this embodiment, the actual gap width is 214, and it is possible to construct a minute gap width that is impossible with mechanical processing.

〔Effect of the invention〕

As described above, according to the present invention, by providing a rounded shape at both ends of the gap, it is possible to prevent the generated magnetic field from spreading, thereby preventing a reduction in reproduction output. In addition, by changing the size of the rounded shape by changing the holding temperature and holding time in the glass fusing process, it has many effects such as the ability to create minute gap widths that are extremely difficult to achieve with machining. .

[Brief explanation of drawings]

FIG. 1 is a front view of a sliding surface of a magnetic head according to an embodiment of the present invention. FIG. 2 is a schematic diagram showing the flow of magnetic flux according to this embodiment. FIG. 3 is a front view of a sliding surface of a magnetic head according to the prior art. FIG. 4 is a schematic diagram showing the spread of magnetic flux flow according to the prior art. FIG. 5 is a schematic diagram showing the reduction in signal width according to the prior art. FIG. 6 is a front view showing a portion of the sliding surface of a magnetic head according to another embodiment of the present invention. 1...First core 2...Central second core 3...
...Third Core 4...Writing-Reading Gap 5...
...Erase gap 6...Round shape 7...Groove shape 8...Glass 9...・Signal 10 that remains as a record...
-・Magnetic flux flow 11...Magnetic flux flow 12...Magnetic flux spread 13...Decreased signal 14...Effective gap width 215... −・・
・Gap width due to machining m16・・・・・・Lighter than the gap Seiko Epson Co., Ltd. representative Patent attorney Mogamisuji (1 other person) Fig. 1 Fue Senzu Fue S Fig. Flute 6

Claims (1)

[Claims] A writing-reading gap whose desired width is regulated by grooves formed on both sides of the magnetic core in a direction perpendicular to the track direction, and a writing-reading gap formed at the rear of the writing-reading gap in the track direction.
A magnetic head comprising erase gaps formed on both sides of a read gap in the track direction and in the vertical direction, characterized in that both ends of the write-read gap and the erase gap have rounded shapes. magnetic head.