JPH01224905A - Floating type magnetic head - Google Patents

Abstract

PURPOSE:To neglect the effect of a pseudo output by providing a cavity bottom part top to regulate the depth of a magnetic cavity on a slider body side. CONSTITUTION:A magnetic substance 7 having a highly saturated magnetic flux density is formed on the facing surface on the medium outflow side of a magnetic cavity 6, while, a cavity bottom part top 10 is provided on a slider body 2 on a medium inflow side. A length (a) of a cavity facing surface 9 is made longer than a cavity depth (b), the final finishing process of the surface of the cavity facing surface 9 is executed by grinding and an Rmax is set at approximately 5-6nm. As shown by an arrow 11, for all the magnetic fluxes reproduced from a pseudo cavity 8, since the cavity depth (a) is long, they return without passing through a main magnetic circuit. Thus, since the cavity length (b) of the pseudo cavity 8 generated between a magnetic substance 7 and its forming surface become shorter and the cavity length (a) becomes longer, the regenerative efficiency of the pseudo cavity 8 becomes smaller, and the pseudo output can be made smaller.

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a floating magnetic head used in a magnetic recording/reproducing device.

[Conventional technology]

In a floating magnetic head made of a magnetic slider body, the gap bottom apex that defines the gap depth of the magnetic gap is not provided in the slider body but in the magnetic core. In recent years, there has been a strong demand for increased recording capacity in magnetic recording and reproducing devices, and as a result, media with high coercivity have come to be used as recording media. The head is required to be made of a material with a higher saturation magnetic flux density than before, and a magnetic material with a saturation magnetic flux density higher than that of the magnetic material constituting the main magnetic circuit is formed on one or both sides of the surface facing the magnetic gap using thin film formation technology. However, in the past, the magnetic material with high saturation magnetic flux density was formed only on the opposing surface of the magnetic gap on the medium outflow side, and the gap depth of the magnetic gap was However, in the prior art described above, the magnetic material 7 having a high saturation magnetic flux density is As shown in FIG. 9, since it is provided on the side of the gap bottom apex lO that defines the gap depth b, as shown in FIG.
The problem is that the waveform has an output 12 that is reproduced from the main magnetic circuit and a pseudo output 13 that is reproduced from the gap 8 between the magnetic body 14 that constitutes the main magnetic circuit and the magnetic body 7 that has a high saturation magnetic flux density. The reason why the reproduced output has a pseudo output 13 as shown in FIG. 1O is that the flow of magnetic flux reproduced from the gap 8 is closed in the pseudo gap 1 as shown in FIG.
This is because, in addition to 1, there is a large amount of magnetic flux 15 that passes through the main magnetic circuit and interlinks the reproducing coil. This is because, as shown in FIG. 9, the bondability between the magnetic body I4, which constitutes the main magnetic circuit below the gap bottom apex IO, and the magnetic body 7, which has a high saturation magnetic flux density, is poor. As shown in Fig. 9, the part below the gap bottom apex IO is formed obliquely with respect to the gap facing surface, so the final finishing process during machining cannot be performed by polishing, and the surface roughness is such that the gap facing surface is Rmax is 5-6 nm while 50-60 nm
It depends on being inferior. Therefore, the present invention is intended to solve the above problems. The object of this invention is to provide a floating magnetic head which is composed of a slider body made of a magnetic material and which eliminates pseudo output. 1. Means for Solving Problems] A floating magnetic head of the present invention includes a gap facing surface formed of a magnetic material and forming a magnetic gap, and a magnetic material having a high saturation magnetic flux density due to the magnetic material on the gap facing surface. A floating type magnetic material comprising: a magnetic core having a coil winding window on the side facing the air gap; bonded to a slider body made of a magnetic material and having an air floating surface while forming a magnetic air gap; The head is characterized in that a gap bottom apex defining the gap depth of the magnetic gap is provided on the slider body side. [Example 1] The present invention will be described in detail below using examples. FIG. 1 is a perspective view of one embodiment of the present invention, and FIG. 2 is an enlarged side view of the vicinity of the magnetic gap 6 of the floating magnetic head l shown in FIG. Magnetic material 7 with high saturation magnetic flux density
is formed on the opposite surface of the medium outflow side of the magnetic gap 6,
The gap bottom apex 10 is provided on the slider body 2 on the medium inflow side. As shown in FIG. 4, the gap bottom apex 10 is formed by grooving the magnetic slider block 18 before forming the air floating surface 4, and the surface facing the gap is polished to Rmax5~. As shown in FIG. 5, a coil winding window 20 is formed by groove machining in the magnetic core block 19 at a preliminary stage in the process of machining the magnetic core 3. At this time, as shown in FIG. 2, it is important that the length a of the gap facing surface 9 is longer than the gap depth b. The final finishing process of the surface of the gap facing surface 9 is performed by polishing Rma
It is important to keep X at about 5 to 6 nm. Since this part is an important point of this embodiment, it will be further explained. Generally, the reason why a pseudo output 13 as shown in Fig. 9 occurs is that a pseudo air gap is created between the air gap facing surface of the main magnetic circuit and a magnetic material having a high saturation magnetic flux density, with respect to the original magnetic air gap. by. The distance between this pseudo gap is much smaller than that of the original magnetic gap, but when considered from the perspective of the reproducing coil, the two are completely equal. Therefore, the rate at which the magnetic flux reproduced from each gap interlinks with the reproduction coil is determined by the reproduction efficiency considered from each gap, and when the reproduction efficiency considered from the pseudo gap is large, the pseudo output also becomes large. Therefore, in order to reduce the pseudo output, it is necessary to make the reproduction efficiency seen from the pseudo gap smaller than the reproduction efficiency seen from the magnetic gap. Now, in general, reproduction efficiency is controlled by the gap depth, gap spacing, or length, and magnetic resistance of the main magnetic circuit, but in the case of this example, the main magnetic circuit is almost the same when viewed from the perspective of both gaps. It is sufficient to consider the depth and length of each void. When the main magnetic circuit is constant, the reproduction efficiency is approximately proportional to the length of the gap and approximately inversely proportional to the depth. Therefore, in order to reduce the regeneration efficiency of the pseudo-gap, the length of the pseudo-gap can be reduced by reducing the surface roughness of the surface facing the air gap of the main magnetic circuit that forms a magnetic material with high saturation magnetic flux density by processing such as polishing. Make it smaller,
In addition, it is necessary to increase the depth of the pseudo void by increasing the length of the surface facing the void. The arrow 11 in FIG. 2 shows how all of the magnetic flux reproduced from the pseudo gap 8 returns without passing through the main magnetic circuit because the gap depth a is long. On the other hand, as shown in FIG. 9, in the conventional magnetic head, the surface roughness is large under the gap bottom apex IO of the pseudo gap, so the length of the pseudo gap is large, and the gap depth is also small. The difference between the feature of the present invention in this embodiment and the prior art is that the regeneration efficiency of the pseudo void becomes large due to the formation of 0, and therefore the pseudo output becomes large. A magnetic material having a high saturation magnetic flux density is formed on the surface facing the air gap of the magnetic core block 19 shown in FIG. It is joined to the body slider block 18 by a technique such as glass bonding. After this air floating surface 4j
5 and a magnetic gap width defining surface 5, the floating magnetic head shown in FIG. 1 is obtained. The third waveform is a waveform reproduced by the floating magnetic head according to this embodiment, but it can be seen that no pseudo output is reproduced at all. [Effects of the Invention] As described above, according to the present invention, the air gap facing surface is made of a magnetic material and forms a magnetic gap, and the air gap facing surface is provided with the magnetic material having a higher saturation magnetic flux density than the magnetic material. A floating magnetic head in which a magnetic core having a coil winding window on the side facing the air gap is bonded to a slider body made of a magnetic material and having an air floating surface while forming a magnetic air gap, Since the gap bottom apex that defines the gap depth of the magnetic gap is provided on the slider body side, the gap length of the pseudo gap that is created between the magnetic body having a high saturation magnetic flux density and the forming surface of the magnetic body. This has the effect that the regeneration efficiency of the pseudo void becomes smaller and the pseudo output becomes smaller because the void depth becomes larger and the void depth becomes smaller. Also, the apex l of the bottom of the void
When processing O, the 17 can be used as a secondary coil winding window, so it also has the effect of increasing the number of coil windings.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a floating magnetic head according to an embodiment of the present invention. FIG. 2 is an enlarged side view of the vicinity of the magnetic gap of this embodiment. FIG. 3 is a characteristic diagram of the reproduced peak waveform of this embodiment. FIG. 4 is a perspective view of processing the slider body of one embodiment. FIG. 5 is a perspective view of a magnetic core block according to one embodiment. FIG. 6 is a perspective view of the magnetic core block of this example in which a magnetic material having a high saturation magnetic flux density is formed. FIG. 7 is a perspective view of the slider body and magnetic core block of this embodiment joined together. FIG. 8 is a perspective view of a floating magnetic head according to the prior art. FIG. 9 is an enlarged side view of the vicinity of the magnetic gap of a floating magnetic head according to the prior art. FIG. 1O is a characteristic diagram of the reproduction output of a floating magnetic head according to the prior art. l... Floating magnetic helad according to this embodiment 2... Slider body 3... Magnetic core 4... Air floating surface 5... Magnetic gap width defining surface 6... Magnetic gap 7. ...Magnetic material having high saturation magnetic flux density 8...Pseudo gap 9...Magnetic gap opposing surface 10...Magnetic gap bottom apex 11...Magnetic flux closed by the magnetic gap 12...Reproduction from the magnetic gap Output 13...Pseudo output 14 from the pseudo gap...Magnetic body 15 constituting the main magnetic circuit...
Magnetic flux interlinking with the reproducing coil 16...Floating magnetic head 17 according to the prior art...Groove for machining the bottom apex of the magnetic gap 18...Magnetic slider block 19...Magnetic core block 20...Coil winding Line window 21...Glass or above Applicant Seiko Epson Co., Ltd. agent Patent attorney Kisanbe Suzuki (and 1 other person) No. 1 m. FT illustration 8 □Cicada body tracking time? 'f Figure 9 □ Time Figure 10

Claims (1)

[Claims] A gap-opposing surface formed of a magnetic material and forming a magnetic gap is provided, a magnetic material having a higher saturation magnetic flux density than the magnetic material is provided on the air-gap opposing surface, and a coil winding window is provided on the air-gap opposing surface side. In a floating magnetic head formed by adhering a magnetic core having an air-floating surface to a slider body made of a magnetic material while forming a magnetic gap, the bottom apex of the gap defining the gap depth of the magnetic gap is A floating magnetic head characterized by being provided on the slider body side.