JPS60197917A - Manufacture of magnetic head - Google Patents

Abstract

PURPOSE:To improve a yield of a product, and to reduce man-hour by providing a process for forming the first magnetic circuit block and the second magnetic circuit block, a process for forming a magnetic head block, and a process for cutting this magnetic head block. CONSTITUTION:A manufacturing method of a magnetic head is provided with three processes. That is to say, it is provided with a process for forming the first magnetic circuit block b1 and the second magnetic circuit block b2 by butting a pair of magnetic material blocks 1, 3 through gap materials g1, g2, g3 and g4, respectively, a process for forming a magnetic head block b3 by joining both these blocks through a nonmagnetic material layer 5 in the direction crossing those gaps, and a process for sticking this magnetic head block b3 to the first magnetic circuit block b1 and the second magnetic circuit block b2, also providing a difference on a width of the gap of both these blocks and cutting it. In this way, a yield of a product is improved, and the man-hour is reduced.

Description

[Detailed description of the invention] [Technical packaging] This invention relates to a video tape recorder (VT) L).

The present invention relates to a method of manufacturing a magnetic head used in disk recorders and the like.

[Prior art]

Generally, in a home video tape recorder (VTR), a rotary head is used to record and reproduce video signals, and the head traces diagonally to the longitudinal direction of the magnetic tape. On the other hand, recorded video signals are erased by a fixed head (full-width erasing head) that can simultaneously erase the entire width of the magnetic tape. However, in this type of v'r R, there are so-called spliced shots and inserts.

When performing editing work such as the following, the full-width erase head may end up erasing parts that do not need to be erased, or leaving unerased parts. Therefore, the playback screen will be distorted in this part.

Therefore, it is conceivable to install the erasing head as a rotating head close to the video signal recording head, but in order to prevent the erasing head from leaving unerased data, the track width (head width) must be larger than that of the recording head. It has been difficult to manufacture a video signal recording head and an erasing head with a high yield and a small number of man-hours, and to arrange them close to each other.

On the other hand, many types of VTRs have been commercialized that run the magnetic tape at a speed different from that during recording and can perform special playback such as high-speed search playback and slow-motion playback. In order to reduce the noise par on the playback screen during special playback, it has been considered to arrange the heads in one building, but it has also been proposed and implemented to arrange two heads with different head widths close to each other. . In this case as well, it has been impossible to arrange these heads with high precision, high yield, and a small number of man-hours.

[Purpose of the invention]

This invention was made in order to solve these conventional drawbacks. It has a small variation in one dimension of the shape, has a high yield, and also requires less man-hours and costs. The present invention proposes a method of manufacturing a magnetic head that allows heads to be placed close to each other.

〔Example〕

A first embodiment of the present invention will be described below with reference to FIGS. 1 to 4. 1 to 3 are perspective views for explaining a method of manufacturing a magnetic head, and FIG. 84 is a perspective view of a magnetic head obtained by the same method.

This example includes the following three steps.

The first step consists of two steps. One of them is the first
As shown in the figure, a first magnetic core half 1 made of a plate-shaped magnetic material block and a second magnetic core half 2 made of a magnetic material block with an opening-shaped cross section provided with a groove 2a are connected to each other.
By butting them together with the two faces on the inside, and by providing a gap material (Jt, 9t) such as glass on the butt part, the first
This is a step of forming the magnetic circuit block b1. The other one, as shown in Fig. 2, consists of a third magnetic core half 3 made of a plate-shaped magnetic material block and a fourth magnetic core half made of a magnetic material block with a cross-sectional shape having two grooves 4a and 4b. The core halves 4 are butted against each other with the openings 4a and 4b inside, and a gap material such as glass (is, C
This is a step of forming a second magnetic circuit block b by providing J+.

The first to fourth magnetic core halves 1.2.3 and 4 are as follows.

For example, a high permeability magnetic material such as ferrite or Sendust alloy is used. Both first and second magnetic circuit blocks bI
, b, in this example two first magnetic circuits and two second magnetic circuits are formed by the two gaps q+ I(Jt and 93 I94).

In the second step, as shown in FIG. 3, the first magnetic core half 1 of the first magnetic circuit block b and the second magnetic circuit block b are
This is a step of forming a magnetic head block b by joining the third magnetic core half 3 of , with the nonmagnetic layer 5 interposed therebetween.

When joined in this way, the gap qt+92 and the gap (J3. (J4) are positioned at a predetermined interval. In other words, the first core half 1 and the third core half
and the distance l corresponding to the sum of the thicknesses of the three parts of the nonmagnetic layer 5. The nonmagnetic layer 5 is made of ceramic, glass, or the like.

In the third step, the magnetic head block bs is moved from the first magnetic head block b to the second magnetic head block bs, as shown in FIG.
VIk head block b, first cut surface d,
By cutting at , and then cutting at cutting plane d,
This is the process of obtaining a magnetic head H as shown in FIG.

The cut plane d here refers to the gap (width W1 corresponding to the track width of JII92) in the magnetic head H obtained.
and the gap (7!, the width W corresponding to the track width of 94
, the first magnetic head block bl
It is set so that the side of the second magnetic head block b can be cut wide and the side of the second magnetic head block b can be cut narrowly. In this example, W+
>Wt. Further, as described above, the cutting plane d is the same as that of both the first and second magnetic circuit blocks bl.
.

This is a line that cuts each pair of two first magnetic circuits and two second magnetic circuits formed in b2. That is, a magnetic head has a pair of a first magnetic circuit having a gap (Jt) and a second magnetic circuit having a gap q3, and a pair of a first magnetic circuit having a gap q and a second magnetic circuit having a gap q4. This is the surface that separates the magnetic head from the magnetic head.

5 and 6 show a second embodiment.

FIG. 5 is a perspective view for explaining the manufacturing method of this embodiment, and corresponds to FIG. 3, and FIG. 6 is a perspective view of a magnetic head obtained by the same method, and corresponds to FIG. 4. It is. The same reference numerals as in FIGS. 1 to 4 indicate the same or corresponding parts.

This embodiment differs from the first embodiment in that the cut plane d1 in the $1 embodiment is set to the cut plane d3 that diagonally crosses the gaps 9+, qt, (Js, 94).

However, this cut surface d3 has a width W equivalent to the track width of the gap (Js, (Jz) of the resulting magnetic head H.

and gap (J3. Width W equivalent to the track width of .94.

The cut plane d of the first embodiment is different from the cut plane d in the first embodiment in that the purpose is to provide a difference between the
, is the same as . Therefore, the same explanation as in the first embodiment can be given regarding FIGS. 5 and 6.

Since it consists of such a process, the gap q and C1s,
The distance between the gaps q2 and 94 is determined by a distance l corresponding to the sum of the thicknesses of the first core half 1, the third core half 3, and the nonmagnetic layer 5 at the stage of forming the magnetic to rad block b3. The above gap q is determined by the subsequent processing steps such as cutting.

and q3. And the positional relationship between q2 and 94 will not change. Therefore, the magnetic head H manufactured by the above process has less variation in its dimensions, especially in the gap, and the yield as a product is improved.

In addition, cutting in the third step is the final step in manufacturing the magnetic head H, and does not require assembly or other processing work after that, so the number of man-hours is reduced, which is combined with the above-mentioned yield improvement. Therefore, manufacturing costs can be reduced.

Furthermore, in the magnetic head H obtained by this manufacturing method, information is erased in the magnetic core half 1.2 and the gap CI++92, and information is written and read in the magnetic core half 3.4 and the gap (Js, CJ+). Therefore, by using this magnetic head H, it is possible to erase and rewrite only a specific track out of a large number of tracks on a magnetic tape in which various signals are recorded.

It can also be used as a VTI (special playback to RAD) that performs special playback.

In the above explanation, the method of manufacturing a magnetic head for VTI (VTI) was explained, but it can also be applied to devices that record digital information or video signals on floppy disks, etc.
Of course, it is also possible to use the head produced by the manufacturing method of the present invention when two heads with different head widths are provided close to each other.

〔Effect of the invention〕

As explained above, according to the present invention, since the above-mentioned three steps are provided, the yield of the product is high, and the number of man-hours is small, so the cost is low.

It has become possible to arrange two magnetic heads with different head widths close to each other.

[Brief explanation of drawings]

1, 2, and 3 are diagrams for explaining the first embodiment of the present invention, and FIGS.
A perspective view of a magnetic circuit block and a second magnetic circuit block, FIG. 3 is a perspective view of a magnetic head block formed by joining both blocks, and FIG. 4 is obtained by cutting the magnetic head block of FIG. 3. FIG. 5 is a perspective view of the magnetic head; FIG. 5 is a diagram for explaining the second embodiment and corresponds to FIG. 3; FIG. 6 is a perspective view of the magnetic head obtained by cutting the magnetic head block of FIG. FIG. 1......First magnetic core half 2...
...Second magnetic core half CI+, (Jt...
...Gap material b1...First magnetic circuit block 3...Third magnetic core half 4...
...Fourth magnetic core half 9g, (74...
Gap material b2...$2 Magnetic circuit block b3...
・Magnetic head block

Claims (1)

[Claims] forming a first magnetic circuit block and a second magnetic circuit block by butting each pair of magnetic material blocks with a gap material in between; a step of forming a magnetic head block by joining the magnetic head block through a first magnetic circuit block, and a step of cutting the magnetic head block by connecting the first magnetic circuit block to the second magnetic circuit block and making a difference in the width of the gap between the two blocks. A method of manufacturing a magnetic head, comprising the steps of: