JPH0729342A - Magnetic head supporting device and magnetic head - Google Patents

Abstract

PURPOSE:To prevent magnetic characteristics from being deteriorated caused by an external magnetic field. CONSTITUTION:The supporting device is composed of a flexture 7 for fitting a slider 8, a load beam 8 for supporting the flexture 7 and a mount 9 for fitting the load beam 8. At least one member out of the flexture 7, the load beam 8 and the mount 9 consists of a hardly magnetizable material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head supporting device and a magnetic head used in a magnetic disk device or the like.

[0002]

2. Description of the Related Art FIG. 8 is a view showing a conventional magnetic head supporting device. In FIG. The magnetic head 4 is a coil wound around the core of the magnetic head 3, and 5 is a magnetic disk. The air flow generated by the rotation of the magnetic disk 5 causes the magnetic head 3 to maintain a floating clearance A above the magnetic disk 5. Surface.

[0003]

However, in the above-described conventional configuration, in a magnetic head in which at least a part of the magnetic core is formed by a thin film forming technique (for example, a thin film magnetic head, a laminated magnetic head, a laminated magnetic head, etc.). There is a problem that various characteristics (output, asymmetry, bit shift, etc.) of the magnetic head are deteriorated by the external magnetic field.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and an object thereof is to provide a magnetic head supporting device and a magnetic head in which various characteristics of the magnetic head are not deteriorated.

[0005]

In order to achieve this object, at least a part of the supporting device is made of a hard magnetic material.

Further, a soft magnetic material is attached near the magnetic core of the magnetic head.

[0007]

It has been found that the magnetizing phenomenon of the supporting device due to the external magnetic field becomes a problem as a cause of deterioration of various characteristics of the magnetic head. Therefore, with the above structure, it is possible to prevent the magnetizing of the supporting device due to the external magnetic field, and further it is possible to reduce the influence of the magnetic flux generated from the magnetizing supporting device on the magnetic core formed of the thin film. Further, by providing the soft magnetic material near the magnetic core, it is possible to prevent the magnetic core from being magnetized.

[0008]

【Example】

(Embodiment 1) FIGS. 1 (a), 1 (b) and 1 (c) are a front view, a side view and a back view showing a magnetic head supporting device according to an embodiment of the present invention. In FIGS. 1A, 1B and 1C, 6 is a slider, and a magnetic head is mounted on the slider 6. At least a part of the magnetic core of the mounted magnetic head is formed by a thin film forming technique. More specifically, as the magnetic head, a laminated magnetic head, a thin film magnetic head, a magnetoresistive effect magnetic head, and the like can be considered. 7 is a flexure to which the slider 6 is attached, 8 is a load beam that supports the flexure 7,
Reference numeral 9 is a mount for mounting the load beam 8, 10 is a coil wound around the magnetic head of the slider 6, and 11 is a tube provided on the load beam 8 to protect the coil 10.

In this embodiment, at least one of the flexure 7, the load beam 8 and the mount 9 is made of a hard magnetic material. As a matter of course, the most preferable thing is that the flexure 7, the load beam 8 and the mount 9 are made of a hard magnetic material. It is also preferable that at least the flexure 7 near the slider 6 is made of a hard magnetic material. Further, if the portion other than the flexure 7 is made of a hard magnetic material, the characteristics are considerably improved as compared with the conventional case where the supporting device is made of a material that easily magnetizes.

Next, the hard magnetic material will be described. Nonmagnetic materials and soft magnetic materials can be considered as the hard magnetic material. The nonmagnetic material preferably has a residual magnetic flux density (hereinafter abbreviated as Br) of 140 G or less. This means that when Br is 140 G or more, the magnetic flux generated by the magnetization of the support device affects the magnetic core formed of a thin film. As a specific material, a stainless steel material (Br140
G or less) or the like is used. The stainless steel material has a crystal structure that differs depending on the heat treatment applied in the manufacturing process and the manufacturing conditions, and it is possible to manufacture a material having Br of 140 G or less (specific manufacturing conditions vary depending on each stainless steel material, so it should be appropriately determined. The heat treatment also depends on the composition of the material and so must be selected appropriately). In addition, although there are stainless steel materials having Br of 140 G or more depending on manufacturing conditions and the like, it is not preferable to use these as the materials of this embodiment. Further, the stainless steel material is suitable as a constituent material of the flexure 7, the load beam 8 and the like because it is excellent in corrosion resistance and spring property.

Next, the soft magnetic material will be described. As the soft magnetic material, Br is 10 G or less, coercive force (hereinafter abbreviated as Hc) is 0.4 (Oe) or less, and initial permeability (hereinafter abbreviated as μ).
Is preferably 1500 or more. Permalloy or the like can be considered as a specific material.

Next, the characteristics of the magnetic head supporting device of this embodiment and the conventional magnetic head supporting device were compared. First, FIG. 2 compares the output change rates of the magnetic heads, FIG. 3 compares the asymmetry, and FIG. 4 compares the bit shift. These are the properties most susceptible to the magnetisation of the support device.

As the experimental method, a laminated magnetic head (for example, a head provided with a magnetic core in which a metal magnetic film and an insulating layer are alternately laminated between a pair of non-magnetic substrates) is used, and the size and shape of other suspensions are the same. I chose Further, in the magnetic head supporting device of the present embodiment, the constituent material of the supporting device was stainless steel, and the Br thereof was 140G. Further, in the conventional magnetic head supporting device, the constituent material of the supporting device is a stainless steel material, and its Br is 560G. The measurement conditions are as follows.

・ Tester GU
ZIK RMA301 ・ Magnetic disk 3.5 inch 1
600 (Oe) -Number of rotations of magnetic disk 4888 rpm-Measurement position on magnetic disk R = 21.9 mm-Measurement frequency LF / HF = 2.
5 / 9.0 MHz Recording current Iw = 8 wA _pp Flying height 0.10 μm An external magnetic field was compared with various characteristics under the above conditions.

2, FIG. 3, and FIG. 4, the white circles are the measurement results of this embodiment, and the black circles are the measurement results of the conventional example. As can be seen from FIG. 2, FIG. 3, and FIG. 4, in the conventional example, various characteristics deteriorate as the external magnetic field increases, but in the present example, the characteristics do not deteriorate much. It is considered that this is due to the fact that the constituent material such as flexure is made of a hard magnetic material.

As another embodiment, the surface of the flexure 7, the load beam 8, the mount 9 and the like may be coated with a hard magnetic material by a thin film forming technique. A tape-shaped material made of a hard magnetic material may be attached.

In this embodiment, it is described that at least one member of the flexure 7, the load beam 8, the mount 9 and the like may be made of a hard magnetic material, but for example, a plurality of members are made of a hard magnetic material. When configured, the same effect can be obtained even if one member is made of a non-magnetic material and the other member is made of a soft magnetic material. Further, in the present embodiment, the supporting device of the magnetic head supporting device is composed of the members of the flexure 7, the load beam 8 and the mount 9, but the same effect can be obtained even if it is composed of other members. Further, in the present embodiment, an example in which a magnetic head in which at least a part of a magnetic core is made of a magnetic film is mounted on a floating slider has been described. For example, a floppy head or an MT (magnetic tape) head is supported. Even if at least a part of the device is made of a hard magnetic material as in the present embodiment, the same effect can be obtained.

(Embodiment 2) FIG. 5 is a perspective view showing a magnetic head in one embodiment of the present invention. 1 in FIG.
Reference numerals 2 and 13 denote core halves, respectively, and the core halves 12 and 13 have a configuration in which a magnetic core 16 made of a metal magnetic film is sandwiched between non-magnetic substrates 14 and 15, respectively. The core halves 12 and 13 are butted against each other via a magnetic gap 18 and are joined to each other. Reference numeral 17 denotes a soft magnetic plate provided at the bottom. As the soft magnetic plate 17, a plate made of ferrite, a soft magnetic thin film, or the like is used. Further, the thickness of the soft magnetic plate 17 is preferably about 50 μm to 100 μm.

In this way, the soft magnetic plate 1 is provided near the magnetic core 16.
By providing 7, the supporting device is magnetized, and even if the magnetic flux (M in FIG. 5) generated by the magnetization is passing through the magnetic core 16, the soft magnetic plate 17 is provided in the vicinity of the magnetic core 16. Since the magnetic flux M is provided in the magnetic core 1,
I can't reach 6. Therefore, the deterioration of the magnetic characteristics of the magnetic head can be prevented. In this embodiment, the soft magnetic plate 17 is provided on the bottom surface. However, the same effect can be obtained by providing the soft magnetic plate 17 on the L surface and the opposite surface, and the H surface and the opposite surface in FIG. You can get it. Further, although the laminated magnetic head has been described in the present embodiment, the same effect can be obtained in a thin film magnetic head or a magnetoresistive effect magnetic head. That is, by providing the soft magnetic plate in the vicinity of the magnetic core that controls at least one of recording and reproduction, it is possible to prevent the deterioration of the magnetic characteristics caused by the magnetization of the supporting device.

Next, the effect of this embodiment will be described with reference to FIGS. 6 and 7.
Will be described with reference to. 6 and 7 are diagrams showing the output change rate and asymmetry due to the external magnetic field, respectively.
In FIGS. 6 and 7, the white circles represent the present embodiment, and the black circles represent the conventional example. As described above, in this embodiment, that is, in the magnetic head in which the soft magnetic plate is arranged near the magnetic core, it is possible to prevent the characteristic deterioration due to the magnetization of the supporting device.

By combining (Example 1) and (Example 2), it is possible to further prevent deterioration of magnetic characteristics due to an external magnetic field.

[0022]

According to the present invention, since at least a part of the supporting device is made of the hard magnetic material, it is possible to make the supporting device difficult to magnetize. Further, since the soft magnetic material is attached near the magnetic core, even if the supporting device is magnetized, the magnetic flux generated from the supporting device does not affect the magnetic core. Therefore, the deterioration of magnetic characteristics can be prevented.

[Brief description of drawings]

1A is a front view showing a magnetic head supporting device according to an embodiment of the present invention, FIG. 1B is a side view showing a magnetic head supporting device according to an embodiment of the present invention, and FIG. Back view showing the magnetic head support device in the embodiment

FIG. 2 is a diagram showing a relationship between an external magnetic field and an output change rate as a result of comparison of various characteristics between a magnetic head supporting device according to an embodiment of the present invention and a conventional example.

FIG. 3 is a diagram showing a relationship between an external magnetic field and asymmetry as a result of comparison of various characteristics between a magnetic head supporting device according to an embodiment of the present invention and a conventional example.

FIG. 4 is a diagram showing a relationship between an external magnetic field and a bit shift as a result of comparison of various characteristics between a magnetic head supporting device according to an embodiment of the present invention and a conventional example.

FIG. 5 is a perspective view showing a magnetic head in one embodiment of the present invention.

FIG. 6 is a diagram showing a relationship between an external magnetic field and an output change rate as a result of comparison of various characteristics between a magnetic head according to an embodiment of the present invention and a conventional example.

FIG. 7 is a diagram showing a relationship between an external magnetic field and asymmetry as a result of comparison of various characteristics between a magnetic head according to an embodiment of the present invention and a conventional example.

FIG. 8 is a view showing a conventional magnetic head supporting device.

[Explanation of symbols]

 6 Slider 7 Flexure 8 Load Beam 9 Mount 12, 13 Core Half 14, 15 Non-magnetic Substrate 16 Magnetic Core 17 Soft Magnetic Plate

Claims (10)

[Claims] 1. A magnetic head having at least a part of a magnetic core made of a metal magnetic thin film, and a supporting device for supporting the magnetic head, wherein at least a part of the supporting device is made of a hard magnetic material. Characteristic magnetic head support device. 2. A magnetic head support device according to claim 1, wherein the support device comprises a flexure for mounting the magnetic head, a load beam for supporting the flexure, and a mount for mounting the load beam. 3. The magnetic head supporting device according to claim 2, wherein at least the flexure is made of a soft magnetic material. 4. The magnetic head supporting device according to claim 1, wherein a non-magnetic material is used as the hard magnetic material. 5. A magnetic head supporting device according to claim 4, wherein a non-magnetic material having a residual magnetic flux density of 140 G or less is used. 6. The magnetic head supporting device according to claim 1, wherein a soft magnetic material is used as the hard magnetic material. 7. A residual magnetic flux density of 10 G or less and a coercive force of 0.
7. The magnetic head supporting device according to claim 6, wherein a soft magnetic material having an initial permeability of 4 (Oe) or less and 1500 or more is used. 8. A magnetic head in which at least a part of a magnetic core forming a magnetic circuit is formed of a thin film, and a soft magnetic plate is provided in the vicinity of the magnetic core. 9. A core half body comprising a pair of non-magnetic plates and a magnetic core formed by a thin film forming technique between the pair of non-magnetic plates, and bonded to the core half body via a magnetic gap. A magnetic head comprising another core half body and a soft magnetic plate provided on the core half body. 10. The soft magnetic plate is formed of at least one of ferrite and a metallic magnetic material.
Alternatively, the magnetic head according to Item 9.