JP2937966B2 - Magnetic head and magnetic disk drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head used in a magnetic disk drive for storing information, and more particularly to a method for preventing minute dust from adhering to a recording / reproducing element of the magnetic head. Related to the structure of the prevented magnetic head.

[0002]

2. Description of the Related Art A conventional magnetic head used in a magnetic disk drive will be described with reference to FIG. In FIG. 4, the basic configuration of the magnetic head 15 is such that a gas bearing surface is provided opposite to a rotating magnetic recording medium (not shown) and provided on each side in the width direction crossing the inflow / outflow direction. And a slider 32 made of a ceramic structure having a concave-shaped surface 31 sandwiched between the pair of rail surfaces 20a and 20b, and a slider 32 provided on the outflow direction side on the rail surface 20b. Recording / reproducing element section 4
It is composed of

[0003] The magnetic head 15 constructed as described above
Is mounted in the magnetic disk drive and operates as follows.

[0004] The magnetic head 15 flies over the surface of the magnetic recording medium at minute gaps as the magnetic recording medium rotates at a high speed, and reads and writes data on the surface of the magnetic recording medium.

At this time, since the periphery of the recording / reproducing element portion 4 has the lowest flying height characteristic in the circumferential direction (longitudinal direction) of the rail surface 20b of the slider 32, it has dropped from the member used in the magnetic disk drive. When a minute dust or foreign matter generated from a member used in a magnetic disk device adheres to the recording / reproducing element section 4, the recording / reproducing element section 4 is corroded, and data is read / written on a magnetic recording medium. Cannot be read, the flying height of the magnetic head 15 changes greatly, the output of the magnetic head 15 decreases, causing a failure in which data cannot be read, or the flying attitude of the magnetic head 15 fluctuates, and the magnetic recording medium is damaged. In such a case, there is a problem that a fatal head crash failure is induced for the magnetic disk device that causes the magnetic disk device to significantly reduce the reliability of the magnetic disk device.

[0006]

In the above-described conventional magnetic head, when dust or foreign matter is present inside the magnetic disk drive, the flying height and the flying attitude fluctuate, and the output lowering failure occurs.
There is a problem that a head crash failure or the like occurs.

SUMMARY OF THE INVENTION An object of the present invention is to provide a highly reliable magnetic head for a magnetic disk drive which prevents minute dust from adhering to the recording / reproducing element portion and the periphery of the recording / reproducing element portion. It is in.

[0008]

According to the present invention, there is provided a magnetic head comprising:
A pair of rail surfaces that are arranged to face the rotating magnetic recording medium and are provided on each side in the width direction that intersects the inflow / outflow direction and form a gas bearing surface, and a concave portion that is sandwiched between the pair of rail surfaces A recording / reproducing element portion provided on the rail surface on the outflow direction side , a groove provided around the recording / reproducing element portion , and a depth of the groove of 0.25 μm to 0.75 μm
m. The groove shape is determined by the recording / reproduction
Up to the end face on the outflow direction side of the rail surface covering the outer periphery of the element part
It is characterized by having a substantially trapezoidal shape extending. Ion the groove
It is characterized by being formed by a milling method. Further, a magnetic disk drive comprising the magnetic head.

[0009]

Next, an embodiment of a magnetic head according to the present invention will be described with reference to the drawings.

FIG. 1 is a schematic perspective view showing one embodiment of the magnetic head 5 of the present invention.

Referring to FIG. 1, a magnetic head 5 according to the present invention is shown.
Are disposed on opposite sides of a rotating magnetic recording medium (not shown), and are provided on each side in the width direction intersecting the inflow / outflow direction, and a pair of rail surfaces 19 forming a gas bearing surface are provided.
a, 19b, a slider 30 composed of a ceramic structure having a concave-shaped surface 30 sandwiched between a pair of rail surfaces 19a, 19b, and the recording / reproducing element unit 1 provided on the outflow direction side on the rail surface 19b. A substantially trapezoidal groove 2 having a depth of 0.25 to 0.75 μm is formed in the vicinity of the recording / reproducing element 1 for writing and reading data to and from the magnetic recording medium so as to cover the periphery of the recording / reproducing element 1. It is provided in.

The operation of the magnetic head 5 configured as described above and shown in FIG. 1 on a magnetic disk device (not shown) will be described.
This will be described below with reference to FIGS. 2A, 2B, and 2C which schematically show the relative relationship between the magnetic head 5 of the present invention and a magnetic recording medium.

FIG. 2A shows the relative positional relationship between the magnetic head 5 and the magnetic recording medium 6 when the magnetic disk drive is not operating, that is, when the magnetic recording medium 6 is not rotating. The head 5 is stopped in a state called a contact start / stop zone on the magnetic recording medium 6 in a state of being in contact with the magnetic recording medium 6, but when the magnetic disk device is started, the magnetic recording medium 6 starts rotating. Then, as shown in FIG. 2B, when a predetermined rotation speed is reached, air 8 flows between the magnetic head 5 and the magnetic recording medium 6 that have been in contact with the magnetic recording medium 6, and The head 5 floats, and a small gap is maintained between the magnetic recording medium 6 and the magnetic head 5, and reading and writing of data on the magnetic recording medium 6 is performed in this state. At this time, a positive pressure is applied to the rail surfaces 19 a and 19 b forming the gas bearing surface of the magnetic head 5, and a negative pressure is generated in the groove 2 provided near the recording / reproducing element 1.

In the state shown in FIG. 2 (b), when the magnetic disk drive is executing the writing / reading operation of the information and the minute floating dust 9 exists between the magnetic head 5 and the magnetic recording medium 6. The situation is shown in FIG.

According to FIG. 2C, minute dust 9 attached to a member used in the magnetic disk drive falls off, or a foreign matter 10 generated from a member used in the magnetic disk drive becomes magnetic. When mixed between the magnetic head 5 and the magnetic recording medium 6, the groove 2 provided near the recording / reproducing element 1 has a negative pressure. No dust 9 and foreign matter 10
Will be captured in the groove 2.

Accordingly, in the magnetic head 5 of the present invention, since the groove 2 is provided around the recording / reproducing element portion 1, when the magnetic head 5 floats, the groove 2 becomes a negative pressure, and the recording / reproducing element Part 1
And minute dust 9 and foreign matter 1 around the recording / reproducing element unit 1.
0 does not adhere, and fine dust 9 and foreign matter 10 accumulate in the groove 2 provided around the recording / reproducing element 1, and the magnetic head 5 has corrosion and magnetic head. And a change in the flying height between the magnetic head 5 and the magnetic recording medium 6 and a change in the flying posture. It is possible to realize a magnetic disk device with improved reliability that does not cause a crash failure.

Next, referring to the relationship between the depth of the groove 2 and the failure rate of the magnetic disk drive shown in FIG.
The failure rate decreases from μm to 0.5 μm, gradually increases when the depth of the groove 2 becomes 0.5 μm or more, and rapidly increases when the depth exceeds 1 μm. The cause of the rapid increase is that when the depth of the groove 2 exceeds 1 μm, the effect of adiabatic expansion increases, the temperature of the air inside the groove 2 decreases, and dew condensation occurs. This is because the surface of the recording / reproducing element unit 1 is corroded by adhering to the surface of the unit 1 and an output failure occurs.

Therefore, the optimum depth of the groove 2 is set to 0.1.
Needless to say, it is desirable to set the range of 25 μm to 0.75 μm.

[0019]

As described above, according to the magnetic head of the present invention, the minute dust adhering to the member used in the magnetic disk drive falls off or the member used in the magnetic disk drive is removed. If the generated foreign matter is present between the magnetic head and the magnetic recording medium, minute dust and foreign matter are collected in the groove formed near the recording / reproducing element, so that the magnetic head is removed. Of the recording / reproducing element of the magnetic head, the floating gap between the magnetic head and the magnetic recording medium, and the change in the floating posture, which can cause a drop in the output of the magnetic head and damage to the magnetic recording medium. There is an effect that it is possible to provide a magnetic head with improved reliability of the magnetic disk device without causing a fatal head crash failure for the given magnetic disk device.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing an embodiment of a magnetic head according to the present invention.

FIG. 2A is a diagram showing a relative positional relationship between the magnetic head of the present invention and a magnetic recording medium when the magnetic disk device is stopped, and FIG. 2B is a diagram showing the present invention when the magnetic disk device is operating. A diagram showing the relative positional relationship between the magnetic head and the magnetic recording medium,
FIG. 2C is a schematic diagram showing a case where minute floating dust is present between the magnetic head of the present invention and the magnetic recording medium when the magnetic disk device is operating.

FIG. 3 is a diagram showing a relationship between a groove depth of a magnetic head and a failure rate of a magnetic disk drive.

FIG. 4 is a schematic perspective view showing a conventional magnetic head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Recording / reproducing element part 4 Recording / reproducing element part 2 Groove 3 Slider 32 Slider 5 Magnetic head 15 Magnetic head 6 Magnetic recording medium 8 Air 9 Fine dust 10 Foreign matter 19a Rail surface 19b Rail surface 20a Rail surface 20b Rail surface 30 Concave shape Surface 31 concave shape surface

Claims (4)

(57) [Claims] 1. A pair of rail surfaces which are arranged opposite to a rotating magnetic recording medium and are provided on respective sides in a width direction intersecting an inflow / outflow direction and form a gas bearing surface; And a recording / reproducing element portion provided on the outflow direction side on the rail surface,
A groove is provided around the recording / reproducing element portion, and the depth of the groove is
A magnetic head having a thickness of 0.25 μm to 0.75 μm . 2. The magnetic head according to claim 1, wherein the groove has a substantially trapezoidal shape covering the outer periphery of the recording / reproducing element portion and extending to an end face on the outflow direction side of the rail surface. . 3. The magnetic head according to claim 1, wherein the groove is formed by an ion milling method. 4. A magnetic disk apparatus having the claims 1 to magnetic head according to any one of the three.