Patent Application
20100238592
This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2009-066911, filed Mar. 18, 2009, the entire contents of which are incorporated herein by reference.
1. Field
One embodiment of the invention relates to a head slider and a magnetic storage device.
2. Description of the Related Art
In recent years, a distance (a flying height of a head slider) between the flying surface of a magnetic head (head slider) provided to a magnetic storage device and a magnetic storage medium is required to be small to increase the recording density. Specifically, the minimum flying height of the head slider mounted with such a magnetic head is already smaller than or equal to a few nm.
However, if the flying height of the head slider is so small, lubricating agent forming a lubricating layer on the surface of the magnetic recording medium attaches to the head slider.
The situation related to the flying height of the head slider will be described below referring to
The surface of the magnetic recording medium 2 is coated with a lubricating agent for reducing friction between the magnetic recording medium 2 and the head slider 7. Thus, the lubricating agent, which has vaporized while the magnetic recording medium 2 is rotating, attaches to the bottom surface (the flying surface 9) of the head slider 7, and the attached lubricating agent accumulates to thereby become liquid droplets and drops on the magnetic recording medium 2.
In other words, as illustrated in
If the clump of lubricating agent deposited on the flow-out end surface 9a drops on the magnetic recording medium 2, the surface of the magnetic recording medium 2 becomes contaminated, and the clump of lubricating agent inhibits the stable flying of the head slider 7 or damages the magnetic head arranged in the head slider 7.
To avoid such situation, for example, Japanese Patent Application Publication (KOKAI) No. 10-269542 discloses a conventional technology related to a head slider for holding lubricating agent by applying a cured resin to the medium facing surface of the head slider facing the magnetic medium to make the medium facing surface porous.
According to the conventional technology, a cured resin film is formed on the medium facing surface (flying surface) of the head slider.
If the cured resin film is formed on the flying surface of the head slider, the flying property of the head slider is adversely affected. Furthermore, if the lubricating agent is transferred from the medium facing surface of the head slider to a portion close to the flow-out end surface through the medium facing surface, it is difficult to hold the transferred clump of lubricating agent and the like on the head slider. Accordingly, the head slider may be contaminated, the magnetic head may be damaged, and the stability of flying of the head slider may not be maintained.
A general architecture that implements the various features of the invention will now be described with reference to the drawings. The drawings and the associated descriptions are provided to illustrate embodiments of the invention and not to limit the scope of the invention.
Various embodiments according to the invention will be described hereinafter with reference to the accompanying drawings. In general, according to one embodiment of the invention, a head slider comprises a magnetic head, a medium facing surface, a flow-in end surface, a flow-out end surface, side surfaces, and an absorbing structure. The magnetic head is configured to read and write information with respect to a magnetic recording medium. The medium facing surface is configured to face the magnetic recording medium. From the flow-in end surface, an airflow generated by rotation of the magnetic recording medium flows in. To the flow-out end surface, the airflow is guided from the flow-in end surface through the medium facing surface. The side surfaces are located on both sides of the medium facing surface. The absorbing structure is provided to at least one of the flow-out end surface and the side surfaces. The absorbing structure is configured to absorb flowing substances guided with the airflow.
According to another embodiment of the invention, a magnetic storage device comprises a magnetic recording medium, a driver, and a head slider. The driver is configured to rotate the magnetic recording medium. The head slider comprises a magnetic head, a medium facing surface, a flow-in end surface, a flow-out end surface, side surfaces, and an absorbing structure. The magnetic head is configured to read and write information with respect to a magnetic recording medium. The medium facing surface is configured to face the magnetic recording medium. From the flow-in end surface, an airflow generated by rotation of the magnetic recording medium flows in. To the flow-out end surface, the airflow is guided from the flow-in end surface through the medium facing surface. The side surfaces are located on both sides of the medium facing surface. The absorbing structure is provided to at least one of the flow-out end surface and the side surfaces. The absorbing structure is configured to absorb flowing substances guided with the airflow.
A magnetic storage device 1 according to a first embodiment of the invention will be described.
The magnetic recording medium 2 is a magnetic storage medium for recording various types of magnetic information at high recording density, and is rotationally driven in a predetermined direction (counterclockwise direction in
A magnetic head 10 for reading and writing magnetic information inform/to the magnetic recording medium 2 is provided at the end of the head slider 20 supported by the suspension 3.
The VCM 5 controls the position and the speed of the magnetic head 10. Specifically, the VCM 5 increases the speed of the magnetic head 10 or stops the operation of the magnetic head 10 based on current supplied from a VCM driver 16 (
In the magnetic storage device 1 described above, the magnetic head 10 provided at the end of the head slider 20 seeks in a direction across tracks of the magnetic recording medium 2 and changes tracks to be read or written when the suspension 3 rotates on a circular arc having a shaft portion 6 as the center by the drive of the VCM 5. Tracks to be read or written can be changed by moving the magnetic head 10 provided to the head slider 20 in the width direction of the tracks of the magnetic recording medium 2.
The magnetic head 10 moves to a track to be read or written and performs a read operation and a write operation (reading/writing of data) while slightly floating from the surface of the magnetic recording medium 2 by the lifting force generated by the rotation of the magnetic recording medium 2.
The details on the shape of the head slider of the first embodiment will be described referring to
As illustrated in
The facing surface 22 facing the magnetic recording medium 2 illustrated in
As illustrated in
The side pad portions 27 are raised portions arranged to sandwich a part of the center pad portion 26, and allows the lubricating agent to flow out from gaps 32 formed at two areas between the side pad portions 27 and the center pad portion 26.
The flow-in side projection 29 is a raised portion arranged on the flow-in end surface 23 side of the head slider 20, and guides the airflow flowing in from the flow-in end surface 23 towards the flow-out end surface 24 through the facing surface 22.
The region of the facing surface 22 surrounded by the side surfaces 28 and the partition plate 28a forming the flow-in side projection 29 is a negative pressure region 28b. The negative pressure region 28b is formed as a region that receives airflow generated when the head slider 20 moves above the magnetic recording medium 2 at high speed, and generates a pressure in the direction of separating the head slider 20 from the magnetic recording medium 2, i.e., in the direction of increasing the flying height.
By forming three raised portions comprising the center pad portion 26 and the side pad portions 27, and the flow-in side projection 29 with the U-shaped side surface 28 on the flying surface (the facing surface 22) of the head slider 20 as described above, the flying surface is formed not to have a region where the shear stress acted due to the airflow concentrates at one point of the facing surface 22 (flying surface). Specifically, the facing surface 22 is formed in a shape in which the lubricating agent is less likely to accumulate on the facing surface 22.
Furthermore, the facing surface 22 of the head slider 20 is formed in such a shape that the height (inclination) of the facing surface 22 becomes lower towards the flow-out end surface 24 from the flow-in end surface 23 side. Specifically, the shape of the facing surface 22 is formed to be an inclined portion such that the flow of the lubricating agent, which is an unwanted flowing substance, is accelerated from the facing surface 22 of the head slider 20 towards the flow-out end surface 24.
The lubricating agent attached on the facing surface 22 of the head slider 20 thus can be efficiently guided towards the flow-out end surface 24 on the flowing substance discharging side.
In the head slider 20 of the first embodiment, a porous film portion 30 capable of absorbing and holding the lubricating agent attached to the facing surface 22 through the magnetic recording medium 2 is provided on the flow-out end surface 24, from which the airflow flows out and which forms the facing surface 22 of the head slider 20.
In other words, as illustrated in
When manufacturing the head slider 20 illustrated in
The porous film portion 30 such as porous silica is formed on the flow-out end surface 24 of the head slider 20 through coating or vapor deposition method at substantially the same time as the manufacture of a substrate used for manufacturing the head slider 20, or after the substrate is manufactured.
In the first embodiment, the porous ceramic film is formed as a porous film portion 31 on the side end surfaces 25 at the sides of the facing surface 22 of the head slider 20 to cover the entire surfaces of the side end surfaces 25.
As illustrated in
Specifically, the lubricating agent attached to the porous film portion 30 infiltrates to a plurality of holes 30a forming the porous film portion 30 to be held inside the holes 30a.
The lubricating agent guided towards the sides of the facing surface 22 passes from the facing surface 22 through gaps 33 at two areas between the side pad portions 27 and the side surfaces 28, and absorbed and held by the porous film portion 31 provided on the side end surfaces 25.
In the head slider 20 of the first embodiment, the porous film portions 30, 31 are formed on the entire surfaces of the flow-out end surface 24 and the side end surfaces 25 of the head slider 20, from which the airflow flows out. Thus, the lubricating agent attached to the facing surface 22 of the head slider 20 through the magnetic recording medium 2 can be efficiently absorbed and held by the porous film portions 30, 31.
Since the lubricating agent attached to the facing surface 22 of the head slider 20 can be thus smoothly absorbed and held, the accumulation of the lubricating agent can be eliminated. Moreover, the dropping of the lubricating agent onto the magnetic recording medium 2 can be reliably prevented by holding the absorbed lubricating agent.
A head slider 20A according to a second embodiment of the invention will now be described.
As illustrated in
In the head slider 20A of the second embodiment, a long fiber member 40 is attached and fixed to the flow-out end surface 24, from which the airflow flows out, to cover the entire surface of the flow-out end surface 24. A nonwoven fabric coated with lipophilic medical fluid or the like may be used for the long fiber member 40.
In other words, by using the nonwoven fabric coated with lipophilic medical fluid for the long fiber member 40, the infiltration of the lubricating agent can be promoted and the lubricating agent can be held by the long fiber member 40 easily and reliably.
In the second embodiment, a long fiber member 41 is also attached and fixed to the side end surfaces 25 formed on the sides of the facing surface 22 of the head slider 20, similarly to the first embodiment, to cover the entire surfaces of the side end surfaces 25.
As illustrated in
The lubricating agent guided towards the sides of the facing surface 22 passes from the facing surface 22 through the gaps 33 at two areas between the side pad portions 27 and the side surfaces 28, and absorbed and held by the long fiber member 41 provided on the side end surfaces 25.
In the head slider 20A of the second embodiment, the long fiber members 40, 41 are attached and fixed to the entire surfaces of the flow-out end surface 24 and the side end surfaces 25 of the head slider 20A, from which the airflow flows out.
With this configuration, the lubricating agent attached to the facing surface 22 of the head slider 20 through the magnetic recording medium 2 can be efficiently absorbed and held by the long fiber members 40, 41. Thus, the accumulation of the lubricating agent can be eliminated and the dropping of the lubricating agent onto the magnetic recording medium 2 can be reliably prevented.
A head slider 20B according to a third embodiment of the invention will now be described.
As illustrated in
Specifically, a long fiber member 43 is arranged to sandwich the center pad portion 26 at the back end region (a part in the width direction) of the facing surface 22 forming the head slider 20B for efficiently infiltrating of the lubricating agent attached to the facing surface 22.
In this manner, by arranging the long fiber member 43 at the back end region of the facing surface 22, the lubricating agent before reaching the long fiber member 43 arranged on the flow-out end surface 24 can be efficiently absorbed.
In the head slider 20B of the third embodiment, the long fiber members 40, 41 are attached and fixed to the entire surfaces of the flow-out end surface 24 and the side end surfaces 25 of the head slider 20B, from which the airflow flows out, and the long fiber member 40 attached to the flow-out end surface 24 is extended and the extended portion is arranged on apart of the facing surface 22 as the long fiber member 43. Therefore, the lubricating agent that is attached to the facing surface 22 but is not guided to the flow-out end surface 24 by the long fiber member 43 can be efficiently guided to reach the side of the long fiber member 40 arranged on the flow-out end surface 24 and can be absorbed by the long fiber member 40.
A head slider 20C according to a fourth embodiment of the invention will now be described.
As illustrated in
As illustrated in
Specifically, the lubricating agent that has infiltrated to the grooves 50, 51 is sucked up by the capillary phenomenon of the grooves 50, 51, and held inside the grooves 50, 51.
In the head slider 20C of the fourth embodiment, the grooves 50, 51 are formed on the entire surfaces of the flow-out end surface 24 and the side end surfaces 25 of the head slider 20C, from which the airflow flows out, to extend away from the back end of the facing surface 22, and thus the lubricating agent attached to the facing surface 22 of the head slider 20 can be absorbed and held by the grooves 50, 51. Therefore, the accumulation of the lubricating agent can be eliminated, and the lubricating agent can be reliably prevented from dropping onto the magnetic recording medium 2.
The internal configuration of the magnetic storage device comprising the head slider of any of the first to the fourth embodiments will now be described referring to
As illustrated in
The interface 12 controls communication related to various types of information with the host computer 11. Specifically, the interface 12 receives various control signals such as a read signal and a write request signal of data transmitted from the host computer 11 to the magnetic recording medium 2, and transmits the received signals to the HDC 13.
The HDC 13 receives various instructions from the host computer 11 through the interface 12 and sends the instructions to respective functional elements. Upon receipt of a control instruction from the SPM driver 14, the HDC 13 sends the control instruction to the SPM 4.
When the HDC 13 receives a control instruction for the magnetic head 10, the HDC 13 sends the control instruction to the VCM driver 16 or the MCU 17. Upon receipt of a data read/write instruction, the HDC 13 sends the same to the read/write channel 15 to write data, or transmits the data to the host computer 11.
The SPM driver 14 controls the drive of the SPM 4 for rotating the magnetic recording medium 2. Specifically, the SPM driver 14 supplies current for activating the SPM 4 or supplies current for stopping the SPM 4 in response to a request instruction from the MCU 17.
The read/write channel 15 comprises a modulation circuit for writing data to the magnetic recording medium 2, a demodulation circuit for reading data from the magnetic recording medium 2, and the like, to control the read and write of data with respect to the magnetic recording medium 2.
The VCM driver 16 sends various control requests for controlling the speed or the position of the magnetic head 10 to the VCM 5 to drive the VCM 5. Whereby, the speed and the position of the magnetic head 10 are controlled.
The MCU 17 is a controller for controlling the magnetic storage device 1 and comprises an internal memory for storing programs defining the various processing procedures and necessary data.
In the first embodiment, although the porous ceramic film is formed to cover the entire surfaces of the flow-out end surface 24 and the side end surfaces 25 of the head slider 20, the ceramic film may be formed on a part of the flow-out end surface 24 and the side end surfaces 25 rather than their entire surfaces.
Similarly, in the second embodiment, although the long fiber member is attached and fixed to cover the entire surfaces of the flow-out end surface 24 and the side end surfaces 25 of the head slider 20, the long fiber member may be attached and fixed to a part of the flow-out end surface 24 and the side end surfaces 25 rather than their entire surfaces.
Similarly, in the fourth embodiment, although the grooves 50, 51 are formed on the entire regions of the flow-out end surface 24 and the side end surfaces 25 of the head slider 20, the grooves 50, 51 may be formed on a part of the flow-out end surface 24 and the side end surfaces 25 rather than their entire surfaces.
Furthermore, in the first to the fourth embodiments, the long fiber member and the grooves as an absorbing structure for holding the lubricating agent are respectively arranged on the side end surfaces 25 as well as the flow-out end surface 24 of the head slider, the absorbing structure such as the long fiber member and the grooves may be arranged only on the flow-out end surface 24 without requiring the absorbing structure on the side end surfaces 25 of the head slider.
As described above, according to the embodiments of the invention, the head slider arranged in the magnetic storage device is provided with an absorbing structure for absorbing and holding the lubricating agent attached to the medium facing surface on the flow-out end surface of the head slider. Thus, the lubricating agent attached to the head slider can be prevented from forming a clump and dropping onto the magnetic recording medium even if flowing on the head slider. Whereby, contamination with respect to the magnetic recording medium and adverse affect with respect to the flying of the head slider are prevented, and the stability can be enhanced.
While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel methods and systems described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the methods and systems described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2009-066911 | Mar 2009 | JP | national |
