JPH05290533A - Floating type magnetic head - Google Patents

Abstract

PURPOSE:To prevent the C-shaped core of the magnetic head slider of the floating type magnetic head joined to a gimbal from projecting from a floating surface. CONSTITUTION:A viscoelastic material having <=1000 viscosity (cp) and <=200 elastic modulus (kg/cm<2>) is used for a joining layer 17 for joining a magnetic head joining part of the gimbal 6 and the magnetic head slider 5. Then, the viscoelastic material is low in viscosity and is, therefore, good in penetratability. The thickness of the joining layer 17 is thus reduced. In addition, the elastic modulus itself is small and, therefore, the strain of the C-shaped core by the expansion and shrinkage of the joining layer 17 is prevented by the combined effects of both. The projection of the C-shaped core from the floating surface of the magnetic head slider is consequently obviated and the possibility that a magnetic recording medium is damaged is eliminated. Since the magnetic gap of the floating type magnetic head is not damaged, the deterioration in electromagnetic conversion characteristics is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a floating magnetic head for a fixed magnetic disk device used for recording and reproducing data in a computer or the like.

[0002]

2. Description of the Related Art Recently, fixed magnetic disk devices have been made smaller and thinner, and accordingly, the floating magnetic heads have been significantly thinned.

The structure of a conventional floating magnetic head will be described with reference to the side view of the conventional floating magnetic head shown in FIG. 3 and the perspective view of the conventional floating magnetic head shown in FIG. 3 and 4, by joining the C-shaped core 1 and the I-shaped core 2 via a non-magnetic material forming the magnetic gap 3, to obtain a lift force due to the air flow generated with the rotation of the fixed disk. A magnetic head slider 5 having an air bearing surface 4 is formed. Further, the magnetic head slider 5 and the gimbal 6 are joined by a joining layer 7 made of resin, and a load that balances lift with the magnetic head slider 5 is applied via the gimbal 6.
A floating magnetic head is constructed by attaching a load arm 8 to the magnetic head.

The floating attitude of the floating magnetic head is held by a gimbal 6 attached to a load arm 8. In addition, an insulating tube 12 that covers the lead wire 11 of the read / write coil 10 wound around the C-shaped core 1 is fixed by forming a claw 9 on a part of the load arm 8 by cutting and raising. . The closer the magnetic gap 3 of the floating magnetic head is to the magnetic recording medium 13, the higher the recording density and the larger output can be obtained. Therefore, the magnetic gap 3 of the floating magnetic head is usually formed at the position of the air outflow end of the magnetic head slider 5. The position where the magnetic gap 3 of the floating magnetic head is formed is at the magnetic recording medium 13.
It is determined by the shape of the magnetic head slider 5 facing the air bearing surface 4, the load, and the position of the load acting point.

In the in-line type floating magnetic head, the attachment surface of the magnetic head joint portion of the C-shaped core 1 and the I-shaped core 2 where the magnetic head slider 5 is joined to the gimbal 6 is the air bearing surface of the magnetic head slider 5. 4 forms the same plane parallel to 4 and the gimbal 6 is a C-shaped core 1
It is installed so that it is also located on top of. A resin such as a thermosetting epoxy resin is usually used for the joining layer 7 that joins the joining portion of the magnetic head slider 5 and the joining portion of the gimbal 6.

[0006]

However, in the configuration of the conventional in-line type floating magnetic head as described above, the resin such as the thermosetting epoxy resin has a viscosity (CP).
Since it is 1000 to 5000 and the permeability is poor, the thickness of the bonding layer 7 inevitably becomes large and is easily affected by expansion and contraction. Moreover, it is a thermosetting type and has an elastic modulus of 250-
Since it is as large as 10000 (kg / cm ² ), 80-12
When the bonding layer 7 is cooled to room temperature after being heated and hardened at 0 ° C., the bonding layer 7 made of resin contracts in the direction of the arrow 14 and a large bending moment acts on the gimbal 6 in the direction of the arrow 15. Therefore, the C-shaped core 1 has an arrow 16
The stress that deforms in the direction of
A strain of about nm is generated, and the strained portion projects from the air bearing surface 4.

The state at this time is shown in the flatness data of the air bearing surface of the floating magnetic head in the conventional example of FIG. In FIG. 5, the left side of the gap line is the C-shaped core 1,
The right side is the I-shaped core 2. According to the data in FIG. 5, a maximum of 82.5 nm is projected downward (upward in the figure) in the vicinity of the magnetic gap of the C-shaped core 1.

Further, if the contact-start-stop operation is repeated for a long time on the floating type magnetic head having the distortion, the magnetic recording medium 13 is damaged and the recorded information is destroyed. At the same time, since the magnetic gap 3 of the floating magnetic head located on the air bearing surface 4 side of the C-shaped core 1 is damaged, the electromagnetic conversion characteristics are deteriorated as the number of nonmagnetic layers increases.

The present invention solves the above-mentioned problems of the prior art and prevents the distortion of the C-shaped core by reducing the thickness of the bonding layer made of a resin and hardening the bonding layer at room temperature, thereby providing a magnetic recording medium. The purpose is to protect and prevent deterioration of electromagnetic conversion characteristics of the floating magnetic head.

[0010]

In order to achieve the above object, the present invention provides a magnetic head joint portion of a gimbal and a magnetic head with a viscosity (CP) of 1000 or less and an elastic coefficient of 200.
(Kg / cm ² ) The following viscoelastic materials were used for joining.

[0011]

According to the above structure, the viscoelastic material has low viscosity and therefore has good permeability, and the thickness of the bonding layer can be reduced. In addition, since the viscoelastic material cures at room temperature, there is no shrinkage of the bonding layer after the bonding process. Furthermore, since the elastic modulus itself is small, it is less susceptible to the influence of ambient temperature changes, and these together prevent the distortion of the C-shaped core due to the expansion and contraction of the bonding layer.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. The structure of a floating magnetic head according to the present invention will be described with reference to FIG. Since the structure is the same as that of the conventional example except for the bonding layer of No. 2, duplicate description will be omitted and only the bonding layer of the different point will be described.

FIG. 1 is a side view of an in-line type floating magnetic head according to an embodiment of the present invention. In FIG. 1, a magnetic head slider 5 is constructed by joining a C-shaped core 1 and an I-shaped core 2 with a non-magnetic material forming a magnetic gap 3 therebetween. The bonding layer 17 between the magnetic head slider 5 and the magnetic head bonding portion of the gimbal 6 has a viscosity (CP) of 1000 or less and an elastic coefficient of 200.
The following viscoelastic materials (kg / cm ² ) were used. This viscoelastic material is a kind of epoxy resin obtained by reacting epichlorohydrin and bisphenol A under a concentrated alkali catalyst of NaOH, as in the thermosetting epoxy resin of the conventional example. The molecular weight is 400 or less, which is much lower than the molecular weight 1420 of the conventional example.

Since the viscoelastic material used for the bonding layer 17 has a viscosity (CP) of 1000 or less, it has good permeability, and the thickness of the bonding layer 17 can be made thinner than that of the conventional thermosetting epoxy resin. Furthermore, the elastic modulus itself is 200 (kg / cm ² ).
Since it is smaller than the following, due to these synergistic effects, the bonding layer 17
Is less susceptible to expansion and contraction due to increased ambient temperature. In addition, since the viscoelastic material cures at room temperature of 23 ° C,
There is no shrinkage of the bonding layer 17 after the bonding process. Combined with these, even if the bonding layer 17 contracts in the direction of the arrow 18, for example, the bending moment acting on the gimbal 6 in the direction of the arrow 19 is extremely small. Since the bending moment is extremely small, the stress acting on the C-shaped core 1 in the direction of the arrow 20 does not lead to the deformation of the C-shaped core 1.

The state at this time is shown in the flatness data of the air bearing surface of the floating magnetic head in the embodiment of the present invention shown in FIG.
In FIG. 2, the left side of the gap line is the C-shaped core 1 and the right side is the I-shaped core 2. According to the data in FIG. 2, the amount of displacement is 0 in the vicinity of the magnetic gap of the C-shaped core 1, and it is shown that the air bearing surface 4 of the magnetic head slider 5 has no protrusion and the flatness is very good. . Therefore, even if the floating magnetic head of this embodiment is repeatedly contact / start / stop operated for a long time, there is no fear of damaging the magnetic recording medium 13 and destroying the recorded information. At the same time, since the magnetic gap 3 of the floating magnetic head located on the side of the air bearing surface 4 of the C-shaped core 1 does not occur, there is no fear of deterioration of electromagnetic conversion characteristics.

[0016]

According to the floating magnetic head of the present invention, the viscous (CP) 1 is provided between the magnetic head joint portion of the gimbal and the magnetic head.
Bonding was performed using a viscoelastic material having a modulus of elasticity of 000 or less and an elastic modulus of 200 (kg / cm ² ) or less. With this configuration, since the viscoelastic material has low viscosity, it has good permeability and the thickness of the bonding layer can be reduced. In addition, since the viscoelastic material cures at room temperature, there is no shrinkage of the bonding layer after the bonding process. Furthermore, since the elastic modulus itself is small, it is less susceptible to the influence of ambient temperature changes, and these together prevent the distortion of the C-shaped core due to the expansion and contraction of the bonding layer. Therefore, the C-shaped core does not project from the air bearing surface of the magnetic head slider, and there is no fear of damaging the magnetic recording medium. Further, since the magnetic gap of the floating magnetic head is not damaged, the electromagnetic conversion characteristics are not deteriorated.

[Brief description of drawings]

FIG. 1 is a side view of a floating magnetic head according to an embodiment of the present invention.

FIG. 2 is flatness data of an air bearing surface of a floating magnetic head according to an embodiment of the present invention.

FIG. 3 is a side view of a conventional floating magnetic head.

FIG. 4 is a perspective view of a conventional floating magnetic head.

FIG. 5 is flatness data of an air bearing surface of a floating magnetic head in a conventional example.

[Explanation of symbols]

 1 C-shaped core 2 I-shaped core 3 Magnetic gap 4 Air bearing surface 5 Magnetic head slider 6 Gimbal 7 Bonding layer 8 Load arm 9 Claw 10 Read / write coil 11 Lead wire 12 Insulation tube 13 Magnetic recording medium 14 Arrow 15 Arrow 16 Arrow 17 Joining layer 18 arrow 19 arrow 20 arrow

Claims (1)

[Claims] 1. A floating magnetic head in which a magnetic head is attached to a load arm via a gimbal, and a viscous (CP) is provided between a magnetic head joint portion of the gimbal and the magnetic head.
A floating magnetic head characterized by being bonded using a viscoelastic material having a modulus of 1000 or less and a modulus of elasticity of 200 (kg / cm ² ) or less.