JPS60154316A - Straddle erase type magnetic head - Google Patents

Abstract

PURPOSE:To improve the reliability by conducting surface grinding and forming an erasing magnetic gap with a prescribed organic adhesives so as to attain the reduction in the assembling man-hour and also uniform characteristic. CONSTITUTION:A face 13 in contact with recording and reproducing magnetic cores 1, 2 of slides 9, 9' made of a nonmagnetic substance where magnetic poles 51, 51' at the tip of erasing magnetic cores 5, 5' are projected and imbedded to a sliding face with the magnetic medium is surface grinding so as to be flush with the magnetic poles 51, 51'. The bonding face 13 and both side faces of the magnetic cores 1, 2 forming the gap 21 are bonded by an organic adhesives of epoxy group mixed with granular or cylindrical inorganic material or inorganic minute powder such as glass having a particle power slightly smaller than the gaps 51, 51'. Thus, the assembling man-hour is decreased, the uniform characteristic is obtained and the reliability is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field The present invention relates to a magnetic head for recording and reproducing digital signals on a magnetic medium in a digital magnetic recording and reproducing device such as a floppy disk device.

(b) Conventional magnetic heads used in floppy disk devices include tunnel erase heads, which have erasing heads on both sides of the recording/reproducing head that provide magnetic gaps in the same direction, and tunnel erase heads, which have magnetic gaps on both sides of the recording/reproducing head. There is a straddle erase head in which an erasing magnetic pole is arranged with a gap between the recording/reproducing head and the erasing magnetic pole, and erasing is performed by leakage magnetic flux between the gap between the recording/reproducing head and the erasing magnetic pole.

All of these magnetic heads use an erasing head to magnetically shape and erase the distortion or disturbance on both sides of the recording signal caused by the recording/reproducing head (secondly, the signal generated when the magnetic head is misaligned from the track). This is intended to prevent deterioration of the noise-to-noise ratio.

As shown in FIG. 1, the conventional straddle erase head has a recording/reproducing head in which a recording/reproducing gap is formed at the joint between magnetic core 1 and magnetic core 2, and a closed magnetic path is formed with magnetic core 3. Signals are exchanged with the magnetic medium by the recording/reproducing winding 4 wound around the magnetic medium. Further, the erasing head includes sliders 9, 9 made of non-magnetic material.
The magnetic cores 5, 5+ embedded in the magnetic cores 5, 5+ and the lower bent portions 8, 81 of the magnetic core 6, around which the erasing winding 7 to which the erasing signal is supplied are wound, are in magnetic contact to form a closed magnetic path. Ru.

In other words, this type of magnetic head has a sliding surface with the magnetic medium shown in FIG.
As shown in the figure, the magnetic cores 1 and 2 forming the recording/reproducing magnetic gap 21 have magnetic pole portions 51 and 51' on the sliding surface with the magnetic medium.
The magnetic cores 5, 51 protruding from the erase magnetic gap 52.
52'.

An important characteristic of these straddle erase heads is the erase rate, which indicates the degree of erasing, due to the erase magnetic gap 5.
2.52', and the dimensional accuracy of the erasing magnetic gap 52, 52' must be well controlled in order to obtain a specified erasing rate. Therefore, in order to maintain the dimensional accuracy of the erasing magnetic gap 52, 52', the magnetic cores 1 and 2 of the recording/reproducing head are
The magnetic pole portion 51.5 of the erase head near the magnetic gap 21 of
1' is polished in advance by a dimension corresponding to the erasing magnetic gap 52, and then the sliders 9, 91 in which the erasing magnetic core 5.5' is embedded are bonded with adhesive 1.
A method is used to form a magnetic head by bonding at zero.

In addition, as shown in another example in FIG. 5, the vicinity of the magnetic pole parts 51, 51' of the magnetic cores 5, 51 embedded in the slider 9, 91 is erased from the joint surface 13 of the recording/reproducing magnetic cores 1, 2. This is a method in which a dimension corresponding to the magnetic gap 52 is polished in advance.

Further, as in another conventional example shown in FIG. 6, sliders 9 and 91 are embedded with magnetic pole portions 51 and 51' of magnetic cores 5 and 51 for erasing heads protruding from the sliding surface with the magnetic medium. The joint surface 13 with the reproducing magnetic core 1.2 is connected to the magnetic pole part 51.5.
Process it on the same surface as 1'. A spacer 11 having the same dimensions and thickness as a predetermined erasing magnetic gap is formed on a part of the processed joint surface 13 by means such as sputtering or vapor deposition. After that, adhesive 10 such as low melting point glass or epoxy resin is applied to the adhesive surface 13 of one slider 9.91.
An assembly method is used in which the magnetic cores 1 and 2 are bonded together.

(c) Problems with the conventional method In the conventional method shown in FIGS. 4 and 5, the processing for forming the erasing magnetic gap involves not only plane polishing of the bonding surface 13 but also the side surface of the recording/reproducing magnetic core 1.2. , or slider 9
It is necessary to polish the vicinity of the magnetic pole portion 51 of the recording/reproducing magnetic cores 1, 2, . . . into a concave shape. Or polishing is performed after assembling the erasing magnetic core 5 and slider 9.

However, there were drawbacks such as misalignment or breakage of the magnetic core 1.2.5 or the slider 9, resulting in poor workability. Also, in the case of Fig. 6, it is extremely good to flatten the surface, but the spacer 1
It is difficult to control the thickness of 1. Furthermore, since the recording and reproducing magnetic cores 1 and 2 and the slider 9 are bonded with an epoxy adhesive, the epoxy adhesive, which is less hard, comes out on the sliding surface of the magnetic medium, so if used for a long time, the adhesive 10 will deteriorate. Dust or magnetic powder from the scraped magnetic medium may adhere to the recessed portion of the slider 9, which may cause malfunctions, resulting in a lack of reliability.

B) Purpose of the present invention The purpose of the present invention is to eliminate the drawbacks of the conventional method, perform the polishing process only by plane machining, form the erasing magnetic gap with an organic adhesive mixed with granular inorganic powder, and reduce the number of assembly steps per assembly. The purpose is to reduce the amount of heat, obtain uniform characteristics, and improve reliability.

(E) Constituent of the present invention A slider 9 made of a non-magnetic material in which the erasing magnetic core 5 is embedded, with the magnetic pole part 51 protruding from the sliding surface with the magnetic medium, is flat-polished so that the bonding surface 16 is flush with the side surface of the magnetic pole part 51. The bonding surface 13 and both sides of the recording and reproducing magnetic cores 1 and 2 forming the recording and reproducing magnetic gap 21 on the sliding surface are made of glass or alumina powder or the like having a diameter corresponding to the size of the erasing magnetic gap. A straddle erase type magnetic head that is clamped and bonded with an epoxy-based organic adhesive mixed with inorganic material powder, or an epoxy-based organic adhesive mixed with inorganic material powder such as glass or alumina powder and fine powder. This is Kashiyumi Isai.

(f) Embodiment of the present invention As shown in FIG. 7, an embodiment of the straddle erase head of the present invention includes an erasing magnetic core 5゜51 with a magnetic pole portion 51, 51' at the tip thereof as a sliding surface with a magnetic medium. Each slider made of a non-magnetic material buried in a protruding manner? , 9'' magnetic cores 1 and 2 for recording/reproduction are plane-polished so as to be flush with the magnetic pole portions 51 and 51''. An erasing magnetic gap 51° 51° is formed between the joint surface 13 of the slider 9° 9' processed in this way and both side surfaces of the recording/reproducing magnetic cores 1 and 2 forming the recording/reproducing magnetic gap 21. A granular cylindrical or fibrous inorganic material such as glass, alumina, or silica with a diameter slightly smaller than the dimensions of the above, or a layer of approximately 1 layer in diameter than these. Adhesion is performed using an epoxy-based organic adhesive 10 mixed with finely powdered inorganic material.

That is, according to the present invention, as shown in FIGS. 8 and 9, the dimension g of the erasing magnetic gap 51 is defined by the diameter dimension d of the powder grains 12, and the space between these powder grains 12 is bonded with the adhesive 10. Filled. In addition, in FIG. 9, when a fine powder 12 whose diameter is about AD smaller than the powder particles 12 in the organic adhesive 10 is mixed, the thermal expansion of the adhesive 10 is smaller than that of the core magnetic material or glass. Since the adhesive is large, it is preferable to mix the powder grains 12 and the fine powder 12' in order to increase the accuracy of the 9th dimension g, and to mix the powder particles 12 and the fine powder 12' in equal amounts or with a smaller amount of the adhesive 10. It should be noted that since the diameter of the powder particles 12 or fine powder 12' used here is uniform in size from 3 to 70 μm, the erasing magnetic gap 51.51' is sufficiently large.
dimensions can be secured.

(g) Effects of the present invention As described above, according to the present invention, the joining surface 1 of the erasing magnetic gap 52 of the erasing magnetic head of the straddle head
3 requires only surface polishing, and powder grains 1 of a certain size
2 allows easy dimensional control.

It is easy to assemble, has excellent workability, and can reduce costs.

[Brief explanation of the drawing]

Figure 1 is an external perspective view showing the structure of a conventional straddle erase head, Figure 2 is a bottom view showing the sliding surface with the magnetic medium in Figure 1, and Figure 3 is a cut taken from A-4' in Figure 2. 4, 5 and 6 are bottom views of the straddle erase head showing the erasing magnetic gap assembled by the conventional polishing method, and FIG. 7 is the polishing according to the present invention. FIG. 3 is a bottom view of the straddle erase head showing the erasing magnetic gap assembled by processing and adhesion. 8 and 9 are enlarged views of the erasing magnetic gap according to the present invention. Note that 1, 2.3.5.5', 6: magnetic core, 4: recording/reproducing winding, 7: erasing winding, 9.9' varnish slider. 10: adhesive, 11 varnish spacer, 12: powder particles. 121: Fine powder, 13: Joint surface, 21: Magnetic gap for recording and reproduction, 51.51': Magnetic pole part, 52.52':
Magnetic gap for erasing Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9

Claims (2)

[Claims] (1) An erasing magnetic core in which both sides of two recording/reproducing magnetic cores are butted against each other to form a recording/reproducing magnetic gap are separated by a predetermined erasing magnetic gap, and the magnetic pole portion at the tip protrudes onto the sliding surface of the magnetic medium. In the straddle erase head, which is held at the joint surface of a slider made of a non-magnetic material embedded with a slider, the joint surface is flat-polished so that it is flush with the side surface of the magnetic pole portion facing the recording/reproducing magnetic core. and a straddle formed by sandwiching and adhering the joint surface and both side surfaces of the recording/reproducing magnetic core with an organic adhesive mixed with inorganic powder particles having a diameter corresponding to the size of the erasing magnetic gap. Erase type magnetic head. (2) An erasing magnetic core in which both sides of the two recording/reproducing magnetic cores are butted against each other to form a recording/reproducing magnetic gap with a predetermined erasing magnetic gap in between, and the magnetic pole portion at the tip protrudes onto the sliding surface of the magnetic medium. In a straddle erase head that is held between the joint surfaces of a slider made of a non-magnetic material embedded therein, inorganic powder particles having a diameter corresponding to the erasing magnetic gap are connected between the joint surfaces and both sides of the recording/reproducing magnetic core. A straddle erase type magnetic head made by sandwiching and adhering a and a fine powder having a smaller diameter with an organic adhesive.