JPS58222417A - Magnetic head - Google Patents

Abstract

PURPOSE:To minimize the level variation and to ease the mass-production, by separately positioning the sound recording gap of an exclusive sound recording head and the reproducing gap of an exclusive reproducing head on separated circular arcs in a prescribed range. CONSTITUTION:A sound recording gap 3 is installed on a circular arc 11 and a reproducing gap 5 is on another circular arc 12, and the arcs 11 and 12 are separate arcs, each having a radius of 1-6mm.. Moreover, the sound recording gap 3 is deviated by 0.2mm. in the opposite direction of the reproducing gap 5 from the contact point 14 of the common tangent 13 of the arcs 11 and 12 and the arc 11, and the reproducing gap 5 is deviated by 0.2mm. in the opposite direction of the sound recording gap 3 from the contact point 15 of the common tangent 13 and the arc 12, and the gaps 3 and 5 are arranged so that they are parallel with each other and face each other. Furthermore, the interval (d) between both gaps 3 and 5 is set to <=2.4mm..

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic head, and in particular, a recording head and a playback head suitable for an audio cassette tape recorder that records and plays back on a magnetic medium on tape are housed in one Herad case. This invention relates to a magnetic head with little level fluctuation.

A magnetic head in which a recording sound head and a playback head are housed in a single Herad case was devised as a magnetic head for computers.
There was one with the configuration shown in the figure. Figure #E1 is an external view of a dual-gap magnetic head with a gap spacing of 2.4 mm or less.
1 is a Herad case, 2 is a recording head, 3 is its recording gap, a 4-digit playback head, and 5 is its playback gap. In this case, the recording gap 3 and the playback gap 5 are positioned on one circular arc, and the interval α between the recording gap 3 and the playback gap 5 is 2.4fl.
It is as follows.

In this case, recording and playback characteristics can be maximized, but recording is performed with one gap.

The disadvantage is that the level fluctuation is larger than that of a single-gap magnetic head that performs reproduction. On the other hand, the second
As shown in the figure, there is one in which the recording gap 3 of the sound recording head 2 and the reproduction gap 5 of the reproduction-only head 4 are located on different circular arcs 6.7 having the same size and the same shape. However, in this case, the recording gap 3 and the playback gap 5 are the common tangent 8 and the arc 6 of the arcs 6 and 7, respectively.
, 7, and the distance between the recording gap 3 and the playback gap 5 is 3M due to the structure.
That's all for now.

As a result, the gap between recording and playback images cannot be accommodated within the vat of the audio cassette tape recorder, resulting in a problem that level fluctuations become large.

Furthermore, since the recording gap 3 and the reproduction gap 5 are located at the contacts 9 and 10, respectively, extremely high gap positioning accuracy is required, which also has the drawback of making mass production difficult.

The present invention was developed in view of the above, and its purpose is to provide a magnetic head that can reduce level fluctuations and that can be easily mass-produced. The recording gap of the dedicated head and the playback gap of the playback-only head are each located on separate arcs with a radius of 1 to 6H, and the common tangents of the two arcs are mutually connected to each other from the point of contact touching the two arcs. The point is that the gap is positioned on the opposite side of the other gap by 0.2.

The present invention will be described in detail below with reference to the embodiment shown in FIG. 3 and FIG. 4.

FIG. 3 is an external view showing an embodiment of the magnetic head of the present invention. In Fig. 4, numeral 1 is a head case, 2 and 4 are sound recording heads housed inside the head case 1, respectively.
The head is for playback only, and the 3.5 is a head for recording sound 2.
, the recording gap and the playback gap of the playback-only head 4.

By the way, in the embodiment of the present invention, the recording gap 3
is on the arc 11, and the reproduction gap 5 is on the arc 1. It is above;
^1: "Juku 11.12 is a separate arc with a radius of 1 to 6-, and the arc 11° 120 common tangent 1
3 and the arc 11.12 are respectively 14.15, the recording gap 3 is located at a position KO = 0.2 m on the opposite side of the playback gap 5 from the contact point 14,
The playback gap 5 is located at a position shifted by C' = 0.2M from the contact point 15 to the opposite side of the recording gap 3, and the recording gap 3 and the playback gap 5 are parallel to each other and are arranged to face each other. . Further, the interval d between the recording gap 3 and the reproduction gap 5 is set to be 2.4 or less.

It is. Therefore, the conventional cylindrical grinding has been replaced with parallel grinding.

Figure 4 is a diagram showing the experimental results of the relationship between the gap position on the arc and the level fluctuation, and the gap position is the contact point 1 in Figure 6.
The gap position corresponding to 4t or 15 is shown as zero, outside means the direction opposite to the other gaps, and inside means the same direction as the other gaps. As can be seen from the results in Fig. 4, when the gap position shifts inward by 0.1M or more from the position of the contact point 14 (or 15) on the arc 11 (or 15), the level fluctuation of the head increases; , at the gap position shifted outward by within 0.5 mm from the position of the contact point 14, the level fluctuation of the head is small and remains approximately the same value.

Therefore, in the present invention, as described above, the positions of the recording gap 3 and the playback gap 5 are set at the contact point 1, respectively.
The position was set to the outside of the position 4.15, that is, a position shifted within a range of 0.3M from Qj+w in the opposite direction to other adjacent gaps, so that the level fluctuation was 1 dB or less.

Claims (1)

[Claims] 1. A magnetic recording head and a playback head are housed in one head case, and a recording gap of the recording head and a playback gap of the playback head are opposed in parallel.・'In the head, the recording gap and the playback gap are each located on separate arcs with a radius of 1 to 6H, and the common tangents of the two arcs are connected to each other from the point of contact touching the two arcs. A magnetic head characterized in that the magnetic head is positioned on the opposite side of another gap at a predetermined distance. 2. The magnetic head according to claim 1, wherein the predetermined distance is in the range of 0.1 to 0.3 tan.