JPS6271014A - Manufacture of multi-track magnetic head - Google Patents

Abstract

PURPOSE:To process long-wavelength signals with a track having a wide gap section and short-wavelength signals with another track of a narrow gap section, by forming plural track sections under a condition where a pair of half bodies of a magnetic block are united to one body. CONSTITUTION:After the gap forming surfaces of half bodies 11a and 11b of a magnetic block finished with prescribed accuracy are finished to partially have stepped sections of desired level differences at optional locations, the half bodies 11a and 11b are joined to each other by welding by glass and comb- line working is performed on them so as to form track sections 14a and 14b and 15a-15d with prescribed intervals and widths. Then nonmagnetic layers 16a-16f are formed by filling the spaces between each track section with glass, etc. After the layers 16a-16f are formed, the united body is cut into two parts from a plane perpendicular to the joining plane of the half bodies 11a and 11b and each track section 14a and 14b and 15a-15d is separated into two parts. Then wide gap sections 12a and 12b and narrow gap sections 13a-13d are respectively installed to optional locations of the track sections 14a and 14b and 15a-15d and coils are independently wound around the sections below each track section. Thus a multi-track magnetic head 11 is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a multi-track magnetic head having a plurality of wide gap portions and a plurality of narrow gap portions.

As shown in Fig. 1, in the conventional magnetic head of this dish, after integrating and joining the magnetic block halves of 1m and lb through an operating gap 2, tracks 81 to 8f are provided at predetermined intervals, and there is a gap between each track. Filled with non-magnetic materials 4a to 4'' such as glass,
By forming the working gaps 21 to 2r, which are narrow gap portions, a magnetic head 1 having multi-tracks can be obtained.

It goes without saying that the centers of the working gaps 21 to 2f are arranged in a straight line 11.

Generally, magnetic heads with multi-tracks are used for recording (
It is composed of a pair of heads, one for writing (for writing) and one for reproduction (for reading), but since they are composed of the same elements except for the track width and gap length, in the following, to simplify the explanation, we will use the first head. The function and operation of one magnetic head 1 shown in the figure will be explained.

A coil (not shown) consisting of a predetermined number of turns is attached to the lower part of each track 8h to 8'', and when recording, a current is applied to each of the tracks 8a to 8.
Magnetic flux enters the magnetic medium from the working gaps 21 to 2C and creates magnetized tracks recorded at predetermined intervals on the magnetic medium:
This is formed.

Conversely, during reproduction, magnetic flux enters the head from the magnetized track recorded on the magnetic medium through the working gaps 21 to 2f, and the magnetic flux crossing the coil is detected as a reproduction voltage signal.

Multi-track magnetic heads often process both analog and digital signals, and if mixed,
In many cases, long wavelength signals and short wavelength signals are recorded and reproduced.
Narrow employment gap 2 m-2r as shown in Figure 1
When recording and reproducing long-wavelength (analog signals) signals with a magnetic head 1 having a multi-track composed of It had the disadvantage of being bad.

This invention was made to eliminate the above-mentioned drawbacks.
The purpose is to set a group of tracks with a wide gap part and a narrow gear part at required positions within the same head, and process long wavelength signals with the track with the wide gap part, and short wavelength signals with the track with the narrow gap part. The present invention provides a method for manufacturing a highly accurate and inexpensive multi-track magnetic head.

This invention will be explained below.

FIG. 2 is a plan view showing a magnetic head manufactured according to an embodiment of the present invention, in which the gap forming surface of the magnetic block halves 11 m, 1 l b finished to a predetermined precision can be positioned at any position (in the figure). Both ends of the laminated track group) are further partially machined into a stepped shape to the required depth to form the wide gap portion described later, and then integrated and joined by glass welding, and the gap is set to the specified spacing and width. comb teeth processing is performed to form track portions 14m, 14b and 15a to 15d,
Nonmagnetic layers 16a to 16f are formed by filling glass or the like in the portions removed by this comb processing, that is, between each track portion, and then cutting the magnetic block halves 11a to llb at right angles to the bonding surfaces. By separating the track portions 14m, 14b and 15a to 15d, the wide gap portion 12&t2b and the narrow gap portion l can be placed at any desired position.
Track portions 14m, 14' having aa to IJId)
A magnetic head 11 having multi-tracks can be obtained by forming coils 14m, 14b and 15m.'' 15d and independently attaching coils to the lower part of each track portion 14m, 14b and 15m.''15d. In addition, the center of each gap formed in this way is of course 9.in-line (arrayed in a straight line), which makes it possible to create a magnetic helad with high-precision multi-tracks.
1 is configured.

Recording (writing) and reproducing (reading) processes are often performed using a pair of magnetic heads, but in order to simplify the explanation here, the function and operation will be explained using FIG. 2.

For recording, each track section 14m, 14b and 15
Coils installed at the bottom of a to 15d (figure omitted)
When a predetermined current is applied to the coil, out of the magnetic flux attracted to the coil, the long wavelength: word (analog signal) is transferred to the track portion 14a.
, 14b, the short wavelength signal (digital signal) enters the magnetic medium through the narrow gap portions 18a to 18d of the track portions 16 to 15d, forming a magnetized trunk at a predetermined position.

On the other hand, in the case of reproduction, the opposite effect of the above operation works, and the magnetic flux is transmitted from the wide gap parts 12m and 12b for longer wavelength signals than the magnetic medium, and from the narrow gap parts 181 to 18d for short wavelength signals to each track part 14m and 14b. and 15-15d, and detect the voltage signal induced in the coil.

In this way, signals with different wavelengths are transferred to the wide gap section 12m.
12b and the narrow gap portion 18aN18d can be respectively operated for recording and reproducing. Therefore, it is possible to provide a custom-made magnetic head 11 having highly accurate multi-tracks.

The stepped gap abutment surface becomes a gap wider than the narrow gap parts 181 to 18d by an amount corresponding to the depth thereof, and the wide gap parts 12m and 12b are formed at the depth of the stepped part.
One step processing that can control the dimensions of the step can be performed by methods such as chemical etching and abrasive grain polishing.The width of the stepped portion is also determined by track separation processing after the gap is formed. It would be better to make it slightly wider with steps, which makes it easier to process. Note that the narrow gap portion 18
Since the manufacture of a to 184 is the same as the conventional one, the details are omitted.

FIG. 8 is a plan view showing a magnetic head manufactured according to another embodiment of the invention. The embodiment of FIG. 2 has track portions 14m and 14b having wide gap portions 12a and 12b.
are set at both ends of the magnetic head 11, but the magnetic head 21 in this embodiment has wide gaps 2 at required positions.
Track portions 24a-24d having 2a-22d and track portions 251-2 having narrow gap portions 28a-28d.
5d, each track portion 24 # to 24 d and 25 a to 25 d has a required track width, and a non-magnetic layer portion made of glass or the like separates each of these track portions 241 to 24 d and 25 a to 25 d. E7a~2? It is possible to obtain a magnetic head 21 having a multi-track with high precision, low cost, and good operability.

In addition, in the above example, two magnetic block halves 21m,
21b has been described, the present invention is not limited to this, and the same effect can be obtained even when the step is applied to only one of the wide gap portions.

As explained above, according to the present invention, a plurality of track sections having a narrow gap section and a wide gap section are integrally formed from a pair of magnetic block halves, so that signals having different recording wavelengths can be processed in any desired manner. Recording and playback can be performed by operating the wide gap section and the narrow gap section at the same position, and since the in-line of each gap section can be ensured with high precision, tape compatibility can be ensured and the characteristics There is an advantage that a magnetic head with good multi-track performance can be provided at low cost.

[Brief explanation of drawings]

681 is a plan view of a conventional magnetic head having multi-tracks, FIG. 2 is a plan view showing a magnetic head manufactured by one embodiment of the present invention, and FIG. 8 is a plan view of a magnetic head manufactured by another embodiment of the present invention. FIG. 3 is a plan view showing a manufactured magnetic head. In the figure, 11.21 is a magnetic head, 11m, 110 and 21m, 2Xb are half magnetic blocks, 12m, 12b and 22a-22d are wide gap parts, 18a-18d and 28a-28d are narrow gap parts, 14m, 14b and 24a-24d are track portions with wide gaps, 15a-15rl and 25a-25d are track portions with narrow gaps, 16m-16f and 27a-2
7h is a nonmagnetic layer. Agent Masuo Oiwa (2 others) Figure 1 Figure 2 Figure 3 Procedural amendment (method) 20 Title of invention Method for manufacturing multi-track magnetic head 3, relationship to the case of the person making the amendment Patent Applicant Address 2-2-3 Marunouchi, Chiyoda-ku, Tokyo Name (601) Mitsubishi Electric Corporation Representative Shiki
Moriya 4, Agent 6, Date of amendment order 6, Full text of the specification to be amended 7, Contents of the amendment (1) As per the engraving and attached sheet of the specification originally attached to the application (no change in content): Up

Claims (1)

[Claims] Stepping is performed on at least one of the gap-forming surfaces of the pair of magnetic block halves by changing the depth of the groove to form a wide gap and a narrow gap, and the pair of magnetic block halves is made of glass. A step of welding and joining together to form an operating gap in the grooved portion, and processing the magnetic block halves with comb teeth so as to form a plurality of track portions having the operating gaps at predetermined intervals. process and
A step of filling a non-magnetic layer into the portion removed by the comb processing, and separating the tracks by cutting the pair of magnetic block halves at right angles to the bonding surface, thereby forming independent wide gap portions in-line. A method for manufacturing a multi-track magnetic head, comprising the steps of forming a plurality of track portions in a narrow gap portion, and independently mounting a coil at the bottom of each separated track.