JPS60609A - Magnetic head - Google Patents

Abstract

PURPOSE:To attain stable magnetic recording and reproduction at all times without causing partial wear by forming a sliding part adhered closely to a specific part of a magnetic recording medium with a type of material having a higher wear resistance than that of other sliding parts. CONSTITUTION:The head is so constructed that magnetic cores 4a, 4b for two channels' share applied with a winding (not shown in figure) are fixed in a shield case 6 by a fixing member such as a resin. A shielding plate 5 for preventing cross-talk is provided between both the channels. A member having a high wear resistance such as ''Sendust,'' amorphous or ferrite is used for the magnetic core 4a easily susceptible to partial wear due to curling and a hard ''Permalloy'' used the same as the material for a conventional example is used for the magnetic core 4b.

Description

TECHNICAL FIELD The present invention relates to a magnetic head, and more particularly to a magnetic head with improved wear resistance.

Prior art In recent years, tape recorders and video tape recorders (hereinafter referred to as VT)
Devices that use magnetic recording, such as the R (referred to as R), are widely used. This type of device uses a magnetic head that performs magnetoelectric conversion while sliding on a magnetic recording medium to convert magnetic recording into electrical signals.

The tiSi diagram shows the configuration around the audio magnetic head of a conventional VTR. In the figure, the reference numeral l indicates the guide post for the tape guide, and the reference numeral 3 indicates the magnetic cores 4a and 4b. This is a magnetic head for audio with. A magnetic tape 2 serving as a magnetic recording medium is stretched by a pinch roller (not shown) or the like, and is pressed against the circularly polished tape sliding surface of the guide boss 1 and the magnetic head 3. At this time, in order to stabilize the running of the tape, the alignment is usually adjusted so that the magnetic tape 2 is pressed against the large diameter portion formed at the upper end of the guide boss ()l. Although tape running is stabilized by such adjustment, a phenomenon occurs in which the upper end of the magnetic tape 2 in contact with the upper end of the guide post 1 is bent.

This phenomenon is called curling, and when the curled part slides on the tape sliding surface of the magnetic head,
There is a drawback that the amount of wear on the sliding portion corresponding to this curled portion is greater than on other portions.

In FIG. 1, the amount of wear on the upper magnetic core 4a on which the curled portion slides is greater than the amount of wear on other portions.

FIG. 2 shows the magnetic core 4a in the configuration of FIG. 1.

In Figure 2, hard permalloy is used as the material of 4b, and the amount of wear after running the magnetic tape 2 for 500 hours is shown. In Figure 2, the length indicated by the symbol X in the figure is 1.0 m + n, and the length indicated by Y. The figure is shown so that the weight is 5.0 gm. Further, here, the two-dot chain line indicates the dimensions before wear, and the solid line indicates the dimensions after wear.

As shown in the figure, the amount of wear after 500 hours is the amount of wear on the magnetic core 4.
There is an abnormally worn part C caused by curling of the tape at the end of a, and the amount of wear in this part Q (±6.0p
m and the wear amount P of other parts 1. 6 compared to OpLm
It has become extremely large, about twice as large.

In particular, when such uneven wear occurs on the sliding surface, the adhesion between the magnetic tape and the sliding surface deteriorates, spacing loss increases, and the initial magnetoelectric conversion characteristics cannot be maintained, resulting in substantial damage. The life of the magnetic head will be significantly shortened. In particular, in the above-mentioned VTR device, the problem caused by the curling described in J- occurs in the audio recording area due to the format of the magnetic tape, and the problem arises that the sound quality of one channel on the magnetic core 4a side deteriorates. .

Purpose The present invention has been made in view of the above points, and an object of the present invention is to provide at low cost a long-life magnetic head that does not cause uneven wear and can always perform stable magnetic recording and reproduction.

EXAMPLES Hereinafter, the present invention will be explained in detail based on examples shown in the drawings.

FIG. 3 shows the structure of the magnetic head of the present invention. The figure shows an audio head used in a VTR similar to that shown in FIG. It has a structure fixed by a fixing material. Further, a blocking plate 5 is provided between both channels to prevent clock talk. In the present invention, a material with high wear resistance, such as sendust, amorphous, or ferrite, is used for the magnetic core 4a, which is susceptible to uneven wear due to curling, and the magnetic core 4b is made of hard permalloy, similar to the conventional example.

With this configuration, the same experiment as described in the conventional example section was conducted, and the results are shown in FIG. FIG. 4 is of the same type as FIG. 2, and as shown in the figure, the amount of wear after 500 hours is the amount of wear Q of the worn portion C caused by curling of the end of the magnetic core 4a.1. 7 layers m, wear amount P of other parts 1. The difference between OJLm and 0.7JLm L is that the tape sliding surface is worn almost uniformly. As described above, according to this embodiment, it was possible to prevent abnormal uneven wear of the magnetic head due to curling.

Next, FIG. 5 shows an example in which the present invention is applied to an audio magnetic head constructed by laminating a large number of magnetic cores.

In the embodiment shown in FIG. 5, the magnetic core consists of seven layers, of which the uppermost magnetic core 4c is the magnetic core 4d,
and a material with better wear resistance than Shield Case 6,
That is, like the embodiment shown in FIG. 3, it is made of sendust, amorphous, ferrite, or the like. Also, other magnetic core 4
d may be made of hard permalloy as in the embodiment shown in FIG.

In the following manner, abnormal uneven wear caused by curling can be prevented even in a magnetic head with a laminated core.

Although the above two embodiments have been shown, in the present invention, since it is only necessary to use materials with high wear resistance in the necessary parts, the construction can be made very inexpensive, and the tape can be uniformly coated, especially in the tape running system where curling occurs. Abrasion characteristics of the sliding surface can be realized, and stable magnetic recording and reproduction can be performed over a long period of time.

In the above embodiments, a highly wear-resistant material was used for the magnetic core corresponding to the curling position in order to prevent uneven wear caused by curling of the tape, but other parts may be uneven due to other causes. Of course, the structure of the present invention is also effective against wear. Even in this case, uniform wear characteristics can be obtained by adjusting the wear resistance of the part where uneven wear occurs and the other parts. Further, the structure of the present invention is of course applicable not only to VTRs but also to magnetic heads of magnetic disk devices.

Effects As is clear from the above explanation, according to the present invention, in a magnetic head that slides on a magnetic recording medium to perform magnetic recording or reproduction, the sliding portion that comes into close contact with a specific portion of the magnetic recording medium is connected to another magnetic head. Since the structure is made of a material with higher wear resistance than the sliding parts, it is possible to provide an excellent long-life magnetic head that does not cause uneven wear and can always perform stable magnetic recording and playback. .

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the configuration around the magnetic head in a conventional VTR, FIG. 2 is an explanatory diagram showing the results of a wear resistance experiment on the configuration of FIG. 1, and FIG. 3 is an example of the magnetic head of the present invention. FIG. 4 is a perspective view showing the structure, FIG. 4 is an explanatory view showing the results of a wear resistance experiment with the structure shown in FIG. 3, and FIG. 5 is a perspective view showing another embodiment of the present invention. 4a to 4d...Magnetic core 5...Shielding plate 6...Shield case Fig. 1 Fig. 2 Fig. 3 Fig. 4

Claims (1)

[Claims] A magnetic head that slides on a magnetic recording medium to perform magnetic recording or reproduction, characterized in that the sliding part that comes into close contact with a specific part of the magnetic recording medium is made of a material that has higher wear resistance than other sliding parts. To magnetic field.