JPS5816530B2 - magnetic head device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic head device, which is capable of extremely well shielding integrally provided recording and reproducing magnetic heads, and has high positional accuracy between the gaps between the respective heads. Provide equipment.

With the goal.

In general, a magnetic head device having a recording magnetic head and a reproducing magnetic head integrated therein is used, for example, to monitor and reproduce a recording signal recorded by the recording magnetic head using the reproducing magnetic head.

death. However, with this type of magnetic head, a problem occurs in that the magnetic flux of the recording magnetic head leaks to the reproducing magnetic head, interfering with normal monitor reproduction.

In order to prevent this, in the past, a shield plate was simply installed between both magnetic heads to block the leakage magnetic flux, but some leakage magnetic flux bypasses the end of the shield plate, so it is not possible to completely block it. There wasn't.

In order to eliminate the above-mentioned drawbacks, the present applicant has previously proposed
No. 42934, ``Magnetic Head Device,'' proposed a magnetic head for reproduction in which a new coil for canceling leakage magnetic flux was wound around the negative core body of the magnetic head, but this magnetic head device was mainly used for measurement. The amount of leakage magnetic flux (hereinafter referred to as "feedthrough") is about -24 dB (however, the playback output when playing back a saturated recorded tape is OdB), which is sufficient for practical use, but it is not used for audio purposes. In order to achieve this, it is necessary to reduce the feedthrough to about -50 dB, which is still insufficient.

In addition, as a conventional magnetic head device, there is one in which the recording and reproducing magnetic heads are manufactured separately and then joined together as one piece. According to this, each magnetic head is individually covered with a shielding case. Although the leakage magnetic flux is limited as much as possible, there is a drawback that it is difficult to accurately determine the mutual height and parallelism of the gaps between the magnetic heads.

Another conventional example is one in which both magnetic heads are integrally formed and the whole is covered with one shield case.
There were disadvantages such as the internal structure was extremely complicated and the number of parts and processes was large.

The present invention eliminates the above-mentioned drawbacks, and an embodiment thereof will be described below with reference to the drawings.

1A and 1B show a partially cutaway front view and a cross-sectional plan view, respectively, of an embodiment of a magnetic head device according to the present invention.

The magnetic head device 1 has a holder 2, and the holder 2 has a second
As shown in the figure, approximately cross section U is made of non-magnetic gold material, for example.
It has a split groove 3 in the center and both arm parts 41.
, 42, a pair of core grooves 4a and 4b for each of the two channels are formed by machining so that the core grooves 4a and 4b are exactly at the same height for each channel.

Reference numeral 5 denotes a core of a recording magnetic head provided for each channel, which consists of core halves 51 and 5□ each made of laminated ferromagnetic metal thin plates such as permalloy, and the core half 52 is wound with a coil 6. Ru.

As shown in FIG. 2, the pair of core bodies 51 are fitted into the grooves 4a of the arm portions 41 of the holder 2 and fixed thereto.

Reference numeral 7 denotes a reproducing magnetic heald core provided for each channel, which is made of the same material as the head 5 and consists of core halves 10, 1□ around which a husband coil 6 is wound.

The pair of core bodies 7□ are fitted and fixed in the grooves 4b of the arm portions 42 of the holder 2, respectively, as shown in FIG. 2.

Further, an end plate 8 for connecting the end 7 of each coil 6 is provided in the lower concave portion of the arm portion 4□.

Holder 2 with core halves 5□, 1□ single-sided as described above
are both outer surfaces 4c of both arm portions 40, 4□ in FIG.

4d are polished in parallel, and at the same time each core 51゜7,
The gap forming surface can be finished.

On the other hand, as shown in FIG. 3, the other pair of core halves 52 of the magnetic recording core 5 are fitted and fixed in the respective quasi 9a of a holder 91 having a predetermined shape and made of the same material as the holder 2. .

Further, a terminal plate 8 for the coil 6 of each core half 52 is provided in the lower concave portion of the holder 91.

Similarly, the other pair of cores 7 of the reproducing magnetic head core 1 are half-dead.
2 is the above holder 9. The terminal plate 8 is similarly cut into the groove 9b of the holder 92, which has approximately the same shape.

Furthermore, the holders 91, 92 have their core monolithic side surfaces 9c and 9d polished, respectively, in FIGS. 1B and 3, and at the same time, the gap forming surfaces of the core halves 52, 12 are finished.

Next, as shown in FIG.
A pair of gap spacers 101 and 102 are inserted between the opposing gap forming surfaces of 2, 7, and 1□, respectively, and the holders 98 and 9□ are fixed to both outer polished surfaces of the holder 2 with screws 11, respectively. is fixed.

Thus, as shown in FIG. 4, an integrated magnetic head body is formed, and on the right side of the figure are the arm portion 41 of the holder 2, the recording magnetic head core 5 (core body 51°5□), the holder 9, A recording magnetic head section 12 is formed on the left side, and a reproduction magnetic head section consisting of an arm 4□ of the holder 2, a reproduction magnetic head core 1 (core halves 11, 1□), and a holder 9□ is formed on the left side. 122 is formed.

Reference numerals 131 and 132 designate shield cases which, as shown in FIG. 4, are box-shaped with one side open and have a pair of window holes 13a and 13b in their upper lids, respectively.

This shield case 13. , 132 are inserted into the slots 3 of the holder 2 with their inner sidewalls encasing the respective magnetic head parts 121 and 122, and are fixed by being single-cut.

Reference numeral 114 denotes a separation plate made of non-magnetic metal such as copper, which is inserted and fixed between the pair of shield cases 131 and 132 in the groove 3 to magnetically separate the shield cases 131 and 13□. .

The shield cases 131, 13□ and separation plate 14 are as follows:
They may be attached to the holder 2 separately and sequentially, or they may be assembled into one piece, fixed together, one at a time.

With the above configuration, each of the magnetic head sections 12. , 122 is 1
They are individually hermetically encapsulated by a pair of shield cases 131 and 132, magnetically separated by a separating plate 14, and mechanically coupled by a holder 2.

Also, from the window holes 13a, 13b, the gap portion 5a of each core 5, 1, ? a are exposed, and finally, the upper surface of this gap portion and the upper surfaces of shield cases 130 and 132 are simultaneously polished and finished to form a tape sliding contact surface 1 as shown in FIG. 1B.

The magnetic head 1 is thus completed. As described above, according to the magnetic head device according to the present invention, in the magnetic head device L, in which a recording magnetic head and a reproducing magnetic head are integrally provided in close proximity, each of the above-mentioned magnetic heads is provided on both outer sides, respectively. A holding member having a substantially U-shaped cross section that holds the core of the head, and a box-shaped holding member with an opening on one side, the side wall of which is inserted through the opening into the U-shaped holding member. a pair of shield cases inserted in the grooves to individually enclose each magnetic head; and a separation plate made of a non-magnetic material inserted between the pair of shield cases in the U-shaped groove of the holding member. The recording and reproducing magnetic heads are individually and almost completely hermetically encapsulated by the pair of shield cases, and each shield case is magnetically isolated by the separation plate. Therefore, each magnetic head is shielded extremely well, and the foot-through of the recording magnetic head is actually measured to be less than 150 dB, and there is no adverse effect on the reproducing magnetic head. parallel polishing to obtain a gap forming surface of each magnetic head.
As a result, it is possible to easily achieve parallelism between the gap grooves of both magnetic heads without the need for assembly adjustment, and the mutual height positional accuracy of the respective gap grooves can be accurately achieved using only machining accuracy when forming the holding member. Because of this, the gap height position of both magnetic heads can be made accurate, and the structure is relatively simple, and each shield case can be easily manufactured and simple by simply covering it and adding more. It has features such as reduced man-hours and vines.

[Brief explanation of drawings]

1A and 1B are a partially cutaway front view and a cross-sectional plan view of an embodiment of the magnetic head device according to the present invention, respectively, and FIGS. 2 to 4 are body views in the middle of the manufacturing process of the above device, respectively. It is. 1...Magnetic head, 2,91.92...
・Holder, 3... Division groove, 41, 4□...
・Arm part, 5,1... Core, 50.52,18,
12...Core organism, 5a, 7a...
Gap part, 6... Coil, 101, 10□・
...Gap spacer, 121.122...
...Magnetic head section, 138.132...Shield case, 14...Separation plate.

Claims (1)

[Claims] 1. In a magnetic head device in which a recording magnetic head and a reproducing magnetic head are integrally provided in close proximity to each other, both outer portions each have a substantially U-shaped cross section for holding the cores of the respective magnetic heads. A side wall of a holding member, each having a box shape with an opening on one side, is inserted into the U-shaped groove of the holding member through the opening to individually cover each magnetic head. 1. A magnetic head device comprising: a pair of shield cases enclosing the holding member; and a separating plate made of a non-magnetic material inserted between the pair of shield cases in a U-shaped groove of the holding member.