JP2000030387A - Recording/reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably shunt a head from a recording/reproducing medium, to avoid absorption at a shunting time and to prevent occurrence of dust by bringing a gentle slope part into contact with the suspension equipment of a recording/reproducing device and forming a lubricant film added with an extreme-pressure agent on the slope part. SOLUTION: A drive base 1 is provided with a ramp member 7 for loading/ unloading a magnetic head suspension group 3, and the tip of the magnetic head suspension 3 is provided with a ramp contact part 4. Wen the magnetic head suspension group 3 exists in a loading state, the magnetic head suspension group 3 exists on a loaded position 5, and when it exists in an unloading state, the magnetic head suspension group 3 is placed on an unloaded position 6. A lubricant comprising primarily a fluorine system compound, etc., added with e.g. a phosphorous system extreme-pressure agent, etc., is applied to the surface part of the ramp member 7 for loading/unloading, and the lubricant film 8 is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording / reproducing apparatus used for a storage device of a computer, and more particularly to a recording / reproducing apparatus having a structure for retracting a head from a recording / reproducing medium.

[0002]

2. Description of the Related Art Among external recording / reproducing devices used in recent computer storage devices, magnetic disk devices and optical disk devices are relatively inexpensive, have a high recording / reproducing speed, and have a large storage capacity. With regard to optical recording, there is a possibility that near-field optical recording will be increasingly used in the future.

[0003] In the future, with respect to these recording and reproducing devices,
It is becoming common to have a structure in which the recording / reproducing device is retracted from the recording / reproducing medium from the viewpoint of the reliability of the device.

In particular, with respect to a magnetic disk device, the spacing between the trailing edge of the magnetic head and the magnetic disk medium has been reduced to about 20 to 50 (nm) due to the increase in recording density. Accordingly, it is required to reduce the unevenness of the magnetic disk medium, and the surface of the magnetic disk medium has been flattened. As the flattening of the magnetic disk medium progresses, a contact start / stop (CS) that starts and stops the apparatus with the magnetic head in contact with the magnetic disk medium
In the magnetic disk drive adopting the S) method, problems such as adsorption of the magnetic head and deterioration of running durability have occurred. For example, as disclosed in Japanese Patent Application Laid-Open No. 7-262716, Load / start / stop the device without bringing the magnetic disk medium into contact with the air bearing surface of the head
A magnetic disk device employing an unloading method is being developed.

A magnetic disk medium used in a magnetic disk device has a CoP magnetic film formed by sputtering after forming irregularities on an NiP-plated aluminum substrate, and further having a durability film thereon. Generally, a protective film is formed for the purpose of improving the properties and corrosion resistance, and a lubricating layer is generally provided on the outermost surface by dipping or spray coating. In addition, an underlayer using a glass substrate, or
A material that forms irregularities on the protective film layer is also used. In a recent magnetic disk medium, the difference in unevenness between a data recording area (data area) and an area for performing CSS (CSS area) is improved to improve the floating property of the data area and prevent the magnetic head from being attracted after CSS. Some adopt a structure that balances both.

[0006] Further, the magnetic head is of the type in which after floating using a conventional positive pressure, a negative pressure is used so that the flying height does not change even in the peripheral speed difference between the inner circumference and the outer circumference of the magnetic disk medium. With the use of magnetic heads, requirements such as running durability over the entire surface of a magnetic disk medium have become strict.

[0007]

In a recording / reproducing apparatus having a structure for retracting a head from a recording / reproducing medium, the importance of ensuring the reliability of a retracting mechanism is increasing year by year.

Here, a case of a magnetic disk device as an example will be described below, but the present invention is also applicable to a recording / reproducing device having the same structure and function.

[0009] Even when the magnetic head floats due to a decrease in the spacing between the trailing edge of the magnetic head and the magnetic disk medium, a phenomenon in which the lubricant on the magnetic disk medium and its modified products adhere to the magnetic head. Is awake. If the magnetic disk drive employing the CSS method is stopped in this state, the rotation of the magnetic disk medium is stopped, and the magnetic head is left on the magnetic disk, suction occurs via these deposits, There is a problem that makes it impossible to restart. In such a case, it is difficult to avoid adsorption even when the unevenness of the CSS area is increased.
In the case of a magnetic disk drive adopting the load / unload method, such a problem does not occur, but the load / unload method is used.
When the unloading is repeated, dust may be generated due to sliding between the ramp portion and the magnetic head suspension, or the magnetic head may not be able to be loaded due to adsorption due to a decrease in surface roughness due to abrasion.

Conventionally, these problems have been solved by examining the shape and material of the ramp portion and optimizing the magnetic head retreat speed. However, it is becoming difficult to take countermeasures in view of the demand for downsizing the current magnetic disk drive and shortening the start-up / fall-down time.

Accordingly, the present invention provides an example of a recording / reproducing apparatus for avoiding dust generation and suction due to sliding of a ramp portion and a magnetic head suspension when a magnetic head of a magnetic disk device is retracted from a magnetic disk. Provided is a magnetic disk device.

[0012]

In order to solve the above-mentioned problems, it is only required that the frictional resistance between the magnetic head suspension and the ramp when the magnetic head is retracted from the magnetic disk medium can be kept low. For that purpose, it is necessary to form a lubricating film capable of stably obtaining a lubricating effect on the sliding portion. The problem with the formation of the lubricating film is that the ramp portion and the magnetic head suspension always repeatedly contact with a relatively small area, which is almost the same. Therefore, the problem is solved by forming a lubricating film in which an extreme pressure additive is added to the lubricant on the sliding portion between the magnetic head suspension and the ramp in order to hardly deteriorate and maintain good repairability upon scattering. be able to.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to examples.

Example 1 As a basic investigation, a change in frictional resistance at the time of pin contact with SUS304, which is a material for a suspension, was investigated. The investigation method was such that sapphire having a radius of curvature of 1 mm was pressurized with 1 gf, the amplitude was 10 mm, and
After a constant reciprocation, a change in the frictional resistance at that time was made 0.02 m / s in one direction from the center of the amplitude.
Was monitored using a strain gauge. Further, the wear depth of the SUS304 after the test was also examined using a stylus type surface roughness meter (a stylus diameter of 0.5 μm). In the investigation, the case where the lubricant was not applied to the sliding portion, the case where the lubricant was applied, and the case where the extreme pressure additive was added to the lubricant were examined. In this test, the fluorine compound shown in Chemical Formula 1 was used as a lubricant at a concentration of 0.1 wt%.
% Solution containing trichlorotrifluoroethane and an extreme pressure additive was added to the solution 1. The phosphorus-based extreme pressure additive shown in Chemical formula 2 was added to the solution 1 in a concentration of 0.005 wt%.
A mixed solution with dissolved PFPE was used. In the present embodiment, the test is performed with this combination, but the lubricant and the extreme pressure additive effective for the present invention are not limited to this combination.

[0015]

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[0016]

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FIG. 1 shows the result of investigation of the change in frictional resistance with respect to the number of reciprocations of sapphire. It can be seen that the application of the lubricant and the addition of the extreme pressure additive are effective in reducing the frictional resistance.

FIG. 2 shows the result of investigation of the wear depth of the sliding portion made of SUS304 material during the test. It can be seen that the addition of a lubricant and an extreme pressure additive is also effective for abrasion of the material.

Embodiment 2 Next, in an actual magnetic disk device, the frictional resistance between the ramp portion and the magnetic head suspension when loading and unloading are repeated is described with reference to a lubricant containing a lubricant and an extreme pressure additive. The effect of was investigated.

FIGS. 3A and 3B are schematic diagrams of a magnetic disk drive having a load / unload mechanism used for the investigation. In the figure, components not directly related to the present embodiment, such as a magnetic disk medium driving spindle motor and a magnetic head carriage driving coil, are omitted. As shown in FIG. 1, the magnetic disk drive includes one or more magnetic disk media 2 mounted at equal intervals on a medium driving spindle motor that rotates at high precision and high speed, and records information on the magnetic disk media 2. Magnetic head suspension group 3 held on a carriage mounted with a magnetic head movable for reproduction
A voice coil motor for driving a magnetic head carriage for driving the carriage at high speed and positioning at high speed;
It is composed of a high-rigidity drive base 1 and the like for supporting these.

Further, the magnetic head suspension 3 has a mechanism for loading / unloading the magnetic head onto / from the magnetic disk medium. The drive base 1 includes a ramp member 7 for loading / unloading the magnetic head suspension group 3.
Is provided with a magnetic head suspension (ramp contact part) 4 at the tip. In the drawing, a magnetic head suspension (load position) 5 when the magnetic head suspension group 3 is in a loaded state and a magnetic head suspension (unloaded position) 6 when the magnetic head suspension group 3 is in an unloaded state are shown. ing.

As shown in section AA of FIG. 2B, the magnetic head suspension (ramp contact portion) 4 rides on the ramp contact portion and the position of the magnetic head suspension is at the unload position 6. ing. This load /
The lubricant of the present invention is applied to the illustrated surface portion of the ramp member 7 for unloading to form a lubricating film 8.

A voice coil motor control circuit for controlling a voice coil motor for driving a magnetic head carriage in accordance with a signal sent from a host device such as a magnetic disk control device; an interface for exchanging signals with the host device; It is connected to a higher-level device via a recording / reproducing processing unit having a read / write circuit for controlling the current flowing through the magnetic head.

The number of the surveyed lamps was determined as follows: the lamp member 7 was not coated with a lubricant, the lamp material 7 was coated with a lubricant, and the lubricant added with an extreme pressure additive was the lamp material 7.
The number of coatings on the surface was 100 each.

As a test method, the magnetic head suspension was sought from a position 6 in the unloaded state to a position having a radius of 25 mm on the 2.5 "magnetic disk medium 2 rotating at a constant speed of 4000 (rpm). (Width 10 mm, cycle 5)
Hz) The number of times of loading was investigated from the time until the loading could not be performed due to an increase in the frictional resistance between the ramp contact portion formed of the polymer and the magnetic head suspension portion (ramp contact portion) 4. In addition, the frictional force that makes it impossible to load is 2 frictional forces per suspension for each drive.
0 (gf) or more.

FIG. 4 shows the results. It can be seen that the sliding resistance of the lamp coated with the lubricant to which the extreme pressure additive was added was excellent also in the magnetic disk device.

FIG. 5 shows the measurement results of the amount of dust generated by loading / unloading. The measuring method was such that a suction port was provided in the vicinity of the lamp part, and the number of dust particles of 0.3 μm or more per minute when the dust was sucked by a dust counter at 30 cubic centimeters per minute was measured. There is a tendency that many lamps do not form a lubricating film in terms of the amount of dust generated. However, even if the number of load / unload times is increased by applying a lubricant containing an extreme pressure additive, the amount of dust generated can be reduced. I understand.

[0028]

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In this example, the extreme pressure additive of the phosphorus type shown in Chemical formula 2 was used. Almost the same effect has been confirmed.

[0030]

By forming a lubricating film in which an extreme pressure agent is added to the ramp portion, the magnetic head suspension during loading / unloading and the ramp portion are prevented from adsorbing, and the amount of dust generated by sliding is reduced. Since it is possible, the reliability of the magnetic disk device can be improved.

[Brief description of the drawings]

FIG. 1 is a graph showing a change in frictional force with respect to the number of reciprocating sapphire slides of the present invention.

FIG. 2 SUS304 with respect to the number of reciprocal sliding of sapphire
5 is a graph showing wear depth.

FIGS. 3A and 3B are a plan view showing a magnetic disk device having a load / unload mechanism and a cross-sectional view taken along line AA of FIG. 3A.

FIG. 4 is a graph showing the number of load failure generating devices with respect to the number of times of loading / unloading.

FIG. 5 is a graph showing a change in the amount of dust generated in a lamp portion with respect to the number of times of loading / unloading.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Drive base, 2 ... Magnetic disk medium, 3 ... Magnetic head suspension group, 4 ... Magnetic head suspension (ramp contact part), 5 ... Magnetic head suspension (load position), 6 ... Magnetic head suspension (unload position), 7: lamp member, 8: lubricating film.

Claims (2)

[Claims] 1. A ramp section of a recording / reproducing apparatus having a structure in which a gentle inclination section (ramp section) and a suspension of a recording / reproducing apparatus (head) are brought into contact with each other to stably retract a head from a recording / reproducing medium. A recording / reproducing apparatus characterized in that a lubricant containing an extreme pressure additive is applied to a portion of the head suspension that comes into contact with the ramp portion and a portion in the vicinity thereof. 2. A method (load / unload method) for retracting the head so that the head flying surface does not contact the recording / reproducing medium when the recording / reproducing medium stops rotating due to the stop of the recording / reproducing apparatus. The recording / reproducing apparatus according to claim 1, wherein: