JPH043006B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic head, and in particular to a magnetic head in which a recording head and a reproduction head suitable for an audio cassette tape recorder that records on and reproduces magnetic media on tape are housed within one head case. This relates to a magnetic head with little level fluctuation.

A magnetic head in which a recording head and a playback head are housed in a single head case was devised as a magnetic head for computers, and conventionally had the configurations shown in Figures 1 and 2. . Figure 1 is an external view of a dual gap magnetic head with a gap spacing of 2.4 mm or less, where 1 is the head case, 2 is the recording head, 3 is its recording gap, 4 is the playback head, and 5 is its playback gap. be. In this case, the recording gap 3 and the reproduction gap 5 are positioned on one arc, and the distance a between the recording gap 3 and the reproduction gap 5 is 2.4 mm or less. In this case, recording
Although the playback characteristics can be maximized, the disadvantage is that the level fluctuations are larger than that of a single-gap magnetic head that records and plays back with one gap. On the other hand, as shown in FIG. 2, the recording gap 3 of the recording head 2 and the playback gap 5 of the playback head 4 are located on different arcs 6 and 7 of the same size and shape, respectively. There is something I did. However, in this case, the recording gap 3 and the playback gap 5 are connected to the common tangent 8 of the arcs 6 and 7 and the contact points 9 and 1 of the arcs 6 and 7, respectively.
0, and the distance b between the recording gap 3 and the reproduction gap 5 is set to be 3 mm or more for structural reasons. As a result, both the recording and playback gaps cannot be accommodated within the audio cassette tape recorder part, resulting in the problem of large level fluctuations. Furthermore, since the recording gap 3 and the playback gap 5 are located at the contacts 9 and 10, respectively, extremely high gap positioning accuracy is required, making mass production difficult.

The present invention has been made in view of the above, and its object is to provide a magnetic head that can reduce level fluctuations and that can be easily mass-produced.

A feature of the present invention is that the recording gap of the recording-only head and the playback gap of the playback-only head are located on separate arcs with a radius of 1 to 6 mm, and the common tangent of the two arcs is
The points are located 0.2 mm apart from the contact points that touch the two arcs on the opposite side of the other gap.

The embodiment of the present invention shown in FIG. 3 and the fourth embodiment will be described below.
This will be explained in detail using figures.

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

By the way, in the embodiment of the present invention, the recording gap 3 is on the arc 11, the playback gap 5 is on the arc 12, and the arcs 11 and 12 are separate arcs with a radius of 1 to 6 mm. , arc 1
When the points of contact between the common tangent 13 of 1 and 12 and the arcs 11 and 12 are 14 and 15, respectively, the recording gap 3 is located at a position c = 0.2 mm on the opposite side of the playback gap 5 from the contact point 14, and the playback gap Gap 5 is on the opposite side of recording gap 3 from contact 15.
The positions are shifted by c'=0.2mm, and the recording gap 3 and the playback gap 5 are parallel to each other, and
They are arranged to face each other. Furthermore, the distance d between the recording gap 3 and the reproduction gap 5 is set to be 2.4 mm or less. Therefore, the conventional cylindrical grinding is replaced with parallel grinding.

Fig. 4 is a diagram showing the experimental results of the relationship between the gap position on the arc and the level fluctuation. The opposite direction from other gaps, and inside means the same direction as other gaps. As can be seen from the results in Fig. 4, the gap position is at the contact point 14 on the arc 11 (or 15).
(or 15), the level fluctuation of that head will become large. On the other hand, if the gap position is shifted within 0.5 mm outward from the position of contact 14, the level fluctuation of that head will be small. , and have almost the same value. Therefore, in the present invention, as described above, the positions of the recording gap 3 and the playback gap 5 are outward from the positions of the contacts 14 and 15, respectively.
The gap was positioned at a distance of 0.1 mm to 0.3 mm in the opposite direction from other adjacent gaps, so that the level fluctuation would be less than 1 dB.

According to the embodiment of the present invention described above, the recording-only head 2 and the playback-only head 4 can be made to have small level fluctuations, and a dual gear head with small level fluctuations can be obtained. Furthermore, if the gap position accuracy is ±0.3 mm, the level fluctuation will be 1 dB or less, so very high gap position accuracy is not required, making mass production easier. Furthermore, since the gap distance d is set to 2.4 mm or less, the recording gap 3 of the recording head 2 and the playback gap 5 of the playback head 4 are located within the part of the audio cassette tape recorder. , level fluctuations are reduced, making it suitable for use in audio cassette tape recorders. It is also fully compatible with metal tape.

As explained above, according to the present invention, there is an effect that level fluctuation can be reduced and mass production can be easily performed.

[Brief explanation of drawings]

Figures 1 and 2 are external views of a conventional dual gap magnetic head, Figure 3 is an external view of an embodiment of the magnetic head of the present invention, and Figure 4 is the relationship between the gap position on an arc and level fluctuations. FIG. 2 is a diagram showing experimental results. 1...Head case, 2...Recording head,
3... Recording gap, 4... Playback-only head, 5
...Reproduction gap, 11, 12...Circular arc, 13...
...Common tangent, 14, 15...Contact.

Claims (1)

[Scope of Claims] 1. A magnetic head in which a recording head and a playback head are housed within a single head case, and a recording gap of the recording head and a playback gap of the playback head face each other in parallel. , the recording gap and the playback gap are each located on separate arcs with a radius of 1 to 6 mm, and the common tangents of the two arcs are opposite to each other from the contact points touching the two arcs, respectively. What is claimed is: 1. A magnetic head characterized in that it is configured to be positioned at a predetermined distance to the side. 2. The magnetic head according to claim 1, wherein the predetermined distance is in a range of 0.1 to 0.3 mm.