JPH0447506A - Magnetic head and its manufacture - Google Patents

Abstract

PURPOSE:To improve positioning and assembling accuracy by joining a nonmagnetic outrigger formed by making adhere plural independent back cores on one terminal in advance with the side plane of a front core. CONSTITUTION:A front core 1a for recording/reproduction and a front core 1b for erasure are unified with a nonmagnetic adhesive part 1c. A back core 2a for recording/reproduction and a back core 2b for erasure are fixed on the side plane confronting with the one terminal of the nonmagnetic outrigger 3a on one side and the foot part sides of the front cores 1a, 1b with an adhesive. The back cores 2a, 2b are assembled to sandwich a joined nonmagnetic outrigger 3a and the nonmagnetic outrigger 3 on the other side between the front cores 1a, 1b loading coils 4a, 4b. Thereby, a manufacturing process can be simplified, and also, assembling accuracy can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a composite magnetic head, for example, a magnetic head suitable for recording and reproducing information on and from a magnetic disk such as a floppy disk. More specifically, the present invention relates to a tunnel erase type magnetic head or a pre-erase type magnetic head having a front core having a recording/reproducing gap and an erase gap, respectively, and a back core having a magnetic circuit of the front core as a closed magnetic path.

(Prior Art) Among magnetic disk devices, for example, floppy disk devices are relatively easy to handle and can record large amounts of data, so they are widely used as external storage devices for personal computers and the like, and their uses are expanding. .

This type of floppy disk device usually uses a bulk type tunnel erase type magnetic head.

Typical examples are shown in FIG. 3 and Part 4. In this magnetic head, a back core 2a for recording and reproducing and a back core 2b for erasing are bonded together via a non-magnetic spacer 2c so that the front core 1a for recording and reproducing and the front core 1b for erasing form independent closed magnetic paths. A composite back core is used. In addition, 3a and 3b are non-magnetic outriggers, 4a
, 4b is a coil, and 5 is a leaf spring.

In addition, as another example, as shown in FIGS. 5 and 6, back cores 12a and 12b are attached to non-magnetic outriggers 3a and 3b.
(Here, recording/playback and erasing are not separated.)
Some are pre-joined.

(Problems to be Solved by the Invention) In this type of magnetic head, the performance is affected by the positioning accuracy of the front core and back core. Among the above conventional techniques, in the case of the former, the joining position 1c of the recording/reproducing section and the erasing section of each of the front core and back core,
2c must match. That is, the recording/reproducing front core and the recording/reproducing back core, the erasing front core and the erasing back core are directly connected to each other, and the recording/reproducing magnetic circuit and the erasing magnetic circuit are magnetically connected to each other in direct contact. It is necessary to realize a state where there is no such thing. For this reason, high precision is required for each component, and positioning precision is also required during assembly. In particular, when the recording capacity is large, it is necessary to narrow the interval between the recording/reproducing gap and the erasing gap, and the center core (the cores on both sides of the lc) is becoming narrower. For this reason, variations in characteristics due to the above-mentioned accuracy become large, and a decrease in yield becomes a problem. On the other hand, in the case of the latter of the conventional techniques, since a back core with integrated functions for recording/reproducing and erasing is used, interference (crosstalk) between recording/reproducing and erasing occurs, which is unfavorable in terms of characteristics.

The present invention has been made to solve the above-mentioned drawbacks of conventional magnetic heads. An object of the present invention is to simplify the manufacturing process and easily improve assembly accuracy in a composite magnetic head used for high-density recording/reproduction, thereby achieving high yield and having excellent electromagnetic conversion characteristics. An object of the present invention is to provide a magnetic head.

(Means for Solving the Problems) In order to solve the above problems, the magnetic head of the present invention has separate back cores corresponding to each front core, that is, a recording/reproducing back core and an erasing back core. exist independently and are not magnetically contacted or bonded to each other,
The back core is fixed to the non-magnetic outrigger in a plane perpendicular to the mutually facing plane of the back core. Then, the non-magnetic outrigger in which the recording/reproducing back core and the erasing back core are joined in this way is joined to the front core having a recording/reproducing gap and an erasing gap, respectively.

In actual production, an integrated magnetic bar for the back core is glued to a non-magnetic outrigger, and the entire cross-section of the magnetic bar and a part of the cross-section of the non-magnetic outrigger are simultaneously grooved to roughly double the magnetic bar. It is preferable to divide it and obtain back cores corresponding to each front core.

(Function) The magnetic head of the present invention has a non-magnetic outrigger to which a recording/reproducing back core and an erasing back core are respectively joined in advance to one end, and a front core having a recording/reproducing gap and an erasing gap, respectively. Therefore, the back core can be fixed to the front core at the same time as the non-magnetic outrigger is installed. Therefore, positioning can also be performed based on the external shape.

Further, the magnetic circuits for recording/reproducing and erasing each form an independently closed magnetic circuit. Therefore, crosstalk is reduced and stable and high electromagnetic conversion efficiency can be achieved.

(Example) 1 and 2 show one embodiment of the invention.

Front core 1a for recording and reproduction and front core 1b for erasing
are integrated by a non-magnetic adhesive IC, and a recording/reproducing back core 2a and an erasing back core 2b are integrated to form a closed magnetic circuit.
are arranged integrally with the non-magnetic outrigger 3a forming a sliding surface so that the side surface thereof is joined to the side surface of the front core.

Here, the above-mentioned both front cores la, lb and both back cores 2a, 2b are M n -Z n 7 elite,
The recording/reproducing front core 1a and the erasing front core 1b are each provided with a recording/reproducing coil 4a, which is made of a ferromagnetic material such as Ni-Zn ferrite, sendust, or an amorphous magnetic material.

And an erasing coil 4b is attached.

One of the nonmagnetic outriggers 3a and 3b is formed into a substantially U-shape and a substantially hollow shape. One non-magnetic outrigger 3
A back core 2a for recording and reproduction and a back core 2b for erasing are attached to one end of the front cores la and lb on the side surface facing the leg side thereof, and are bonded with glass, epoxy-based, acrylic-based, etc.
It is fixed with adhesive such as. This non-magnetic outrigger 3
A can be easily manufactured by the steps shown in FIGS. 9A to 9F. A part of the non-magnetic bar 3 is cut out at the location indicated by the broken line in FIG. 9A, as shown in FIG. 9B, and the magnetic bar 2 is embedded and bonded in the cutout (FIG. 9C). Next, it is formed and ground at the position indicated by the broken line as shown in the same figure to obtain a substantially U-shaped cross section, and the surface facing the front core is mirror-finished.

When shredding at the position shown in Figure E, the magnetic bar is completely cut by groove 10 as shown in Figure F by simultaneous machining or indexing. This poetic sentiment may be inserted horizontally as shown in FIG. 7, or diagonally as shown in FIG.

In this way, the back cores 2a, 2b are connected to the non-magnetic outrigger 3a, and the other non-magnetic outrigger 3b is connected to the front cores la, lb, to which the coils 4a, 4b are attached.
Assemble it by sandwiching it.

At this time, the back side of the front core 1 is the back core 2.
a, 2b and the back side of the non-magnetic outrigger 3b to form a stable mounting structure, and the non-magnetic adhesive part IC and the groove 10 are connected to form two good independent closed magnetic circuits. The positions seem to match. It is difficult to perform this positioning while looking at the non-magnetic adhesive part IC and the groove 10, but if the configuration of the present invention is adopted, one end surface of the external shape is used as a reference plane and the internal non-magnetic adhesive part 1 can be aligned by simply aligning the external shape.
c. It becomes possible to easily align the position of the groove 10.

The material of the non-magnetic outriggers 3a, 3b may be any non-magnetic material such as ceramic or glass such as barium titanate, calcium titanate, magnesium titanate, etc., and preferably the material is the same as that of the front cores la, lb. A material having abrasion resistance of 100% is preferable from the viewpoint of durability and reliability of the magnetic head since it is difficult to cause uneven wear. It is also possible to satisfy the above characteristics by making the general shape of the outrigger a molded product such as plastic and covering only the sliding surface with a wear-resistant metal, metal compound, or oxide layer by thermal spraying or the like.

Here, an example in which the back cores 2a and 2b are bonded in advance to the non-magnetic outrigger 3a has been described in detail, but as shown in FIGS. 10 to 12, a magnetic bar is bonded to the other non-magnetic outrigger 3b and the groove 10 is Alternatively, the back cores 2a, 2b may be formed by forming the back cores 2a, 2b.

(Effects of the Invention) As is clear from the above description, the magnetic head of the present invention has a non-magnetic outrigger with a plurality of independent back cores bonded to one end in advance, and a recording/reproducing gap and an erasing gap. Since it is bonded to the side surface of the front core and the other non-magnetic outrigger is bonded to the opposite surface, the accuracy of positioning and assembling each back core to each front core is improved at the same time as the non-magnetic outrigger is assembled. It has high yield, low crosstalk, and excellent electromagnetic conversion characteristics.

Furthermore, floppy disk drives are required to be thinner, and correspondingly, magnetic heads are also required to be thinner, but by adopting the structure of the present invention, it is possible to reduce the size and reduce the difficulty of assembly due to thinning. can be reduced.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing the configuration of the magnetic head of the present invention;
Fig. 2 is a perspective view after assembly, Fig. 3 is an exploded perspective view showing an example of the prior art, Fig. 4 is a perspective view after assembly, and Fig. 5 is an exploded perspective view showing another example of the prior art. Figure, 6th
The figure is a bottom perspective view after assembly, FIGS. 7A and 7B are respectively a perspective view and a central sectional view of an example of a non-magnetic outrigger according to the present invention, and FIGS. 8A and B are respectively an example of a non-magnetic outrigger according to the present invention. A perspective view and a central sectional view of the example, and FIGS. 9A to 9F are explanatory diagrams of the processing steps of the nonmagnetic outrigger. 10A and 10B are respectively a perspective view and a central sectional view of another example of the nonmagnetic outrigger according to the present invention, and FIGS. 11A and 11B are respectively a perspective view and a central sectional view of another example of the nonmagnetic outrigger according to the present invention. FIGS. 12A and 12B are a perspective view and a center sectional view of another example of the non-magnetic outrigger according to the present invention, respectively. la...Front core 1b for recording and playback...
Front core 2a for erasure...back core 2b for recording/reproduction...back core 3a for erasure.・Non-magnetic alignment trigger・Groove

Claims (1)

[Claims] 1. A plurality of front cores each having a magnetic gap, a back core whose magnetic circuit is a closed magnetic circuit of the front cores, and non-magnetic outriggers located on both sides of these cores to form a sliding surface. In the magnetic head having the above, the back core exists independently corresponding to each front core, and is not in contact with or adhered to each other, and is connected to the non-magnetic outrigger in a plane perpendicular to the mutually facing surfaces of the back cores. A magnetic head is fixed to the. 2. Glue the integrated magnetic bar for the back core to the non-magnetic outrigger, and groove the entire cross section of the magnetic bar and part of the cross section of the non-magnetic block at the same time to roughly divide the magnetic bar into two. 2. The method of manufacturing a magnetic head according to claim 1, wherein back cores corresponding to the respective front cores are obtained.