JP4376236B2 - Magnetic head support mechanism, magnetic head support method, and magnetic disk apparatus - Google Patents

Description

  The present invention relates to a magnetic disk device, and more particularly to a magnetic head support mechanism, a support method, and a magnetic disk device that maintain a stable flying posture by suppressing a pitch angle and a roll angle.

  The magnetic head of the magnetic disk apparatus performs recording and reproduction while flying over the disk surface by about several tens of nanometers by the air flow generated by the rotation of the disk. It is necessary to keep the magnetic head in a stable flying posture in order to perform track seek at high speed and high accuracy, and a mechanism for supporting the magnetic head is important. In addition, the flying height between the magnetic head and the disk has been decreasing year by year due to higher recording density.

  As a support mechanism for such a magnetic head, there is a support mechanism in which a magnetic head is mounted on a load beam via a flexure. FIG. 9 shows an example of this support mechanism. One end of the load beam 300 is attached to the actuator via the base plate 400, and the other end supports the slider 100 by the flexure 200. An actuator is a positioning mechanism that determines the position of a track of a disk that is a recording medium. The load beam 300 applies an appropriate vertical load to the slider 100 to balance the slider 100 with the force that rises due to the air flow with the disk surface. The flexure 200 abuts on a pivot 310 formed on the load beam 300, and moves flexibly by receiving the motion of rolling and pitching of the slider with the pivot 310 as a fulcrum. For this reason, the flexure 200 is formed of a thin, low-rigid material to improve followability, and one end is fixed to the load beam 300 by welding or the like.

  As described above, since the slider 100 has the pivot 310 as a fulcrum to balance the force of floating by the air flow and the force of suppressing the lift of the load beam 300, the slider 100 floats depending on the size and position of the pivot 310. Attitude is greatly affected. Although the flying posture of the slider 100 affects the flying gap amount between the head and the medium, a method of controlling the flying gap amount by an electrostatic actuator has been proposed.

In this proposal, an electrostatic actuator is provided on the air bearing surface of the slider, and a control voltage is applied between the electrode of the electrostatic actuator and the disk to generate an electrostatic force. Is to control. Furthermore, it has been proposed to control the pitch angle and the roll angle by combining the installation positions of one or more electrostatic actuators arranged on the slider (Patent Document 1).
JP 2004-111019 A

  As described above, the flying gap between the magnetic head and the disk is as small as several tens of nanometers and is in the direction of lowering. In such a situation, for example, the slider on which the magnetic head is mounted during track seek, which is the positioning operation of the magnetic head, receives acceleration in the seek direction and causes rolling. The rolling causes a problem that the floating gap amount between the magnetic head and the disk is reduced and the contact probability between the magnetic head and the disk is increased.

  Also, when starting / stopping the magnetic disk device by the load / unload method, if the pitch angle of the slider at the time of loading / unloading is not appropriate, the contact probability between the magnetic head and the disk is also increased. There is.

  Further, the flying gap amount varies depending on the atmospheric pressure using the magnetic disk device. For example, at low altitudes, the air pressure is low because the pressure is low, the force received from the air flow generated by the rotation of the disk is weakened, the slider pitch angle and the amount of flying clearance are reduced, and the probability of contact with the disk is increased. There is a problem.

  Therefore, it is required to control the flying posture of the slider so as to suppress rolling during track seeking, and to control the flying posture so as to control pitching during loading / unloading. Further, when the air pressure is low, it is necessary to control the pitch angle to increase the force received from the air flow.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a magnetic head support mechanism and method, and a magnetic disk device, which can be controlled to a stable flying posture and a flying gap by different methods.

The magnetic head support mechanism, magnetic head support method, and magnetic disk apparatus of the present invention are configured as follows.
(1) 1st invention 1st invention is the support mechanism of the magnetic head which controls a roll angle and a pitch angle by changing the position of a pivot using the piezoelectric element which is a piezoelectric element. The basic structure for supporting the slider is a structure for supporting the slider via a flexure on the load beam .

  The load beam includes a pivot position control mechanism that controls the position of the pivot on the load beam. The pivot position control mechanism includes a pivot plate, a first piezo element, and a second piezo element.

  In the pivot plate, a pivot formed on the pivot plate is in contact with the flexure, and one end portion in the track direction of the pivot plate is in contact with an end portion of the first piezoelectric element that expands and contracts. One end of the pivot plate in the seek direction is in contact with the end of the second piezoelectric element that expands and contracts. The track direction is the direction of the longitudinal axis of the load beam, and the seek direction is the radial direction with respect to the disk. The seek direction is a direction perpendicular to the track direction.

  The first piezo element has an end opposite to the end in contact with the pivot plate as a load beam so as to change the pitch angle of the slider by changing the contact position of the pivot flexure by expansion and contraction of the first piezo element. It is fixed to.

  The second piezo element has an end opposite to the end in contact with the pivot plate so as to change the roll angle of the slider by changing the contact position of the pivot flexure by expansion and contraction of the second piezo element. It is fixed to.

With the above configuration, the first or second piezo element is expanded and contracted to move the pivot, and the flying posture or the floating is provided by applying a force that opposes the force that changes the pitch angle or roll angle that the slider receives by the air flow. It can be controlled to keep the gap constant .

( 2 ) Second Invention The second invention is the magnetic head support method of the first invention.
( 3 ) Third Invention The third invention is a magnetic disk device of the magnetic head support mechanism of the first invention.

  According to the first aspect of the present invention, it is possible to provide a magnetic head support mechanism capable of controlling the flying posture of the slider with respect to pitching and rolling and controlling the flying gap by changing the pivot position using a piezo element.

According to the second invention, it is possible to provide a magnetic head support method capable of controlling the flying posture and the flying gap of the magnetic head as in the first invention.

According to the third invention, it is possible to provide a magnetic disk device having a magnetic head support mechanism capable of controlling the flying posture and the flying gap of the magnetic head as in the first invention.

  An embodiment of the present invention will be described with reference to FIGS.

(First embodiment)
As a first example, an embodiment of the first invention will be described with reference to FIGS. FIG. 1 is a top view of the magnetic head support mechanism according to the first aspect of the present invention as seen from the side, and the bottom view is a view of the top view from below. In the above figure, one end of the load beam 500 is connected to the base plate 400, and the base plate 400 is further connected to an actuator mechanism (not shown) that performs track seeking. A flexure 200 having a V-shaped side surface is connected to the lower surface of the other end of the load beam 500, and the flexure 200 is further connected to the slider 100. In this example, the load beam 500 and the flexure 200 are fixed by spot welding, and the flexure 200 and the slider 100 are fixed by an adhesive. The central portion of the upper side of the V-shape of the flexure 200 forms an opening by etching, and a pivot 511 of a pivot plate 510 described later is in contact with the lower side of the flexure 200 through the opening.

  A pivot plate 510 formed with a pivot is disposed at a position where the flexure 200 on the lower surface of the load beam 500 is disposed, and an end portion of the pivot plate 510 on the inflow side in the track direction (indicated in the lower part of FIG. 1) is The piezoelectric element P520 is in contact with the end of the piezoelectric element. The end of the piezo element P520 facing the end of the pivot plate 510 that is in contact with the pivot plate 510 is fixed to the load beam 500. The other end of the pivot plate 510 is in contact with the leaf spring 540 and receives a force on the inflow side in the track direction. The piezo element P520 is in a state where a predetermined voltage is applied from the beginning to be expanded, and when the voltage is further increased, the pivot plate 510 moves in the direction of the outflow side in the track direction by the extension of the piezo element P520. That is, the extension of the piezo element P520 causes the position of the pivot 511 to move toward the outflow side in the track direction. If the voltage applied first is decreased, the position of the pivot 511 moves from the initial position to the inflow side in the track direction.

  Pivot plate 510 is also in contact with piezo element R530. The connecting position is the end of the pivot plate 510 in the seek direction, and in FIG. 1, the end is in contact with the end of the seek direction on the inner side. The other end of the pivot plate 510 is in contact with the leaf spring 550. The position of the pivot 511 can be moved in the seek direction on the inner side or the outer side by the same function as the piezo element P520.

  The movement of the pivot 511 when the piezo element P520 is extended will be described with reference to FIG. The upper diagram of FIG. 2 shows a state in which the slider 100 is in a floating posture, for example, parallel to the disk. In this state, the piezoelectric element P520 is stretched by applying a predetermined voltage, and the pivot 511 is at the position “a”.

  A view when the voltage is increased from the above state to the piezo element P520 is a lower view of FIG. By applying a voltage to the piezo element P520, the piezo element P520 further expands and moves the pivot plate 510 to the outflow side in the track direction. As a result, the position of the pivot 511 moves from “a” to “a ′”, and the fulcrum position of the slider changes. As a result, the slider 100 is inclined by generating a force that inclines toward the outflow side in the track direction. become.

  Actually, when pitching that tilts toward the inflow side in the track direction occurs in the slider 100, the applied voltage of the piezo element P520 is increased to generate a force that tilts toward the outflow side in the track direction, thereby suppressing the pitching. Do.

  Note that the first and second piezoelectric elements of the means for solving the above-described problems correspond to the piezoelectric element P520 and the piezoelectric element R530, respectively.

  Next, a control flow by the piezoelectric element of the first invention will be described with reference to FIG. The control flow in FIG. 3 is an example of control for setting an appropriate pitch angle during loading / unloading, and control for keeping the floating gap by atmospheric pressure at a constant gap by controlling the pitch angle (measurement of atmospheric pressure in the magnetic disk device). It is assumed that an atmospheric pressure gauge is installed).

  First, it is checked whether or not there is a load or unload signal. If the signal is output, the voltage applied to the piezo element P520 is increased by a predetermined voltage, and the piezo element P520 is expanded. As a result, the pitch angle exerts a force that tilts toward the outflow side in the track direction, and cancels the force that tilts the pitch angle toward the inflow side in the track direction during loading or unloading. This process is a process only when loading or unloading. Therefore, if there is no load or unload signal, the voltage applied to the piezo element P520 at this time is not changed (S100, S110).

  From the next time, the atmospheric pressure data is acquired from the barometer by the control from the time when the magnetic head moves to the disk after the loading time, and the correspondence of the voltage applied to the piezo element P520 with respect to the atmospheric pressure value prepared separately Browse the table. As a result of the reference, since the applied voltage to be set is known, it is determined whether to increase, decrease or change the current applied voltage. If the applied voltage is increased, the applied voltage of the piezo element P520 is increased from the current value to a specified voltage to extend the piezo element P520. If the applied voltage is decreased, the applied voltage of the piezo element P520 is decreased to shrink the piezo element P520. If the acquired atmospheric pressure value does not require a change in pitch angle, the applied voltage to the piezo element P520 is not changed (S120 to S160).

  In the control flow of FIG. 3, the process is repeatedly executed as the magnetic disk device is turned on, and is always controlled.

(Second embodiment)
Next, as a second embodiment, another embodiment of the first invention will be described with reference to FIG. In the second embodiment, a piezo element is installed on a base plate.

  In FIG. 4, a pivot plate 610 that is longer than that of the first invention is disposed on the lower surface of the load beam 600, and a piezo element P 620 and a piezo element R 630 are disposed on the base plate 400. The end portion on the inflow side in the track direction of the load beam 600 is in contact with the piezo element P620, and the end portion on the inner side in the seek direction of the load beam 600 is in contact with the piezo element R630. Here, the leaf springs corresponding to the leaf springs 540 and 550 in FIG. 3 are omitted, but the operation is the same as in the first invention. Compared to the first invention, the piezoelectric elements P and R are arranged on the base plate 400, so that the wiring for applying the voltage is reduced and the manufacturing work is facilitated.

(Third embodiment)
A third embodiment will be described with reference to FIG . The top view of FIG. 5 is a view of the magnetic head support mechanism as viewed from the side. The load beam 700 connected to the base plate 400 supports the slider 100 via the flexure 200, and a pivot 710 formed on the load beam 700. Is in contact with the flexure 200. Up to this point, the mechanism is the same as that described in the prior art in FIG. In FIG. 5, a heater 720 is disposed on the back surface of a pivot 710 formed on the load beam 700.

  When the slider 100 causes pitching and, for example, a force that tilts the slider 100 toward the inflow side in the track direction is generated, current is supplied to the heater 720 to generate heat, and the pivot 710 is expanded by this heat to increase the pivot height. Thus, it is possible to generate a force for tilting the slider 100 toward the outflow side in the track direction and to suppress pitching. The lower diagram in FIG. 5 shows that the heater 720 generates heat, and the pivot height is increased to generate a force that tilts the slider 100 toward the outflow side in the track direction.

(Fourth embodiment)
The fourth embodiment will be described with reference to FIGS. 6 and 7. In contrast to the structure of the load beam 300 having the conventional structure shown in FIG. FIG. 6 shows the structure of the pivot 810 formed on the load beam 800 when it is cut in the seek direction. In FIG. 6, a protrusion a820 and a protrusion b830 are formed at predetermined positions on both sides of the pivot 810, and a heater a821 and a heater b831 are disposed in the recesses of the protrusions, and are fixed with a heat-resistant adhesive (not shown). The flexure 200 in FIG. 6 corresponds to the lower part of the flexure, and fixes the slider 100.

  An example of suppressing rolling in the fourth embodiment is shown in FIG. FIG. 7A shows an example in which rolling occurs in the conventional structure. For example, when the slider is moving in the direction of motion shown in the figure during track seek, the slider is struck by an air flow to generate a roll angle.

FIG. 7B shows that when a roll angle is generated, a current is supplied to the heater b 831 to generate heat, and the protrusion b 830 is raised by thermal expansion to increase the protrusion height, thereby serving as a stopper against the inclination of the flexure 200. . As a result, the roll angle is suppressed and the inclination of the slider can be limited.

Next, the flow of the roll angle control by the heater will be described with reference to FIG. Here, an example of roll angle control during track seek is shown.

  First, it is determined whether or not a track seek state is established by an off-track signal. If there is an off-track signal, it is determined that the track seek is performed, and then it is determined whether the seek direction is seeking from the inner to the outer. If the magnetic head is moving from the inner side toward the outer side, the heater b831 is turned on and energized. The heater b831 generates heat due to the energization, and the height of the protrusion of the heater b831 increases due to thermal expansion. In the flexure 200 tilted by the generation of the roll angle, this protrusion serves as a stopper, and the roll angle is suppressed. If the seek direction is in the direction from the outer side to the inner side, the roll angle is similarly suppressed by turning on the heater a821 (S200-S230).

  Next, it is checked whether there is an on-track signal. If there is an on-track signal, the heater a821 or the heater b831 is turned OFF at that time. If the on-track signal is not output, the heater continues to energize (S240-S250).

  With the above flow, it is possible to suppress the roll angle that occurs during track seek. Except at the time of track seek, the heater a821 and the heater b831 are turned off to improve the followability to the rotating disk.

It is an example (the 1) of the magnetic head support structure of 1st invention. It is an example of the pitching suppression by 1st invention. It is an example of the control flow by the piezoelectric element of 1st invention. It is a magnetic head support structure example (the 2) of 1st invention. It is an example of a magnetic head support structure . It is an example of a magnetic head support structure . It is an example of rolling suppression . It is an example of the control flow by a heater . It is an example of a conventional magnetic head support structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Slider 200 Flexure 300 Load beam 310 Pivot 400 Base plate 500 Load beam 510 Pivot plate 511 Pivot 520 Piezo element P520
530 Piezo element R530
540 Plate spring 550 Plate spring 600 Load beam 610 Pivot plate 611 Pivot 700 Load beam 710 Pivot 720 Heater 800 Load beam 810 Pivot 820 Protrusion a
821 Heater a
830 Protrusion b
831 Heater b

Claims (3)

A magnetic head support mechanism for supporting a slider having a magnetic head mounted on a load beam via a flexure,
The load beam has a pivot position control mechanism including a pivot plate and first and second piezoelectric elements,
The pivot plate has a pivot formed on the pivot plate in contact with the flexure, and one end portion in the track direction of the pivot plate is in contact with an extending end portion of the first piezoelectric element. One end in the seek direction is in contact with the expanding and contracting end of the second piezo element,
The first piezo element is opposed to an end in contact with the pivot plate so as to change a pitch angle of the slider by changing a contact position of the flexure of the pivot by expansion and contraction of the first piezo element. The end to be fixed to the load beam,
The second piezo element is opposed to an end in contact with the pivot plate so that the roll angle of the slider is changed by changing the contact position of the flexure of the pivot by expansion and contraction of the second piezo element. The end to be fixed to the load beam,
A magnetic head support mechanism. A magnetic head support method for supporting a slider mounted with a magnetic head via a flexure on a load beam having a pivot position control mechanism comprising a pivot plate and first and second piezoelectric elements,
A pivot is formed on the pivot plate, the pivot is brought into contact with the flexure, one end in the track direction of the pivot plate is brought into contact with an extending end of the first piezoelectric element, and the pivot plate One end in the seek direction is in contact with the expanding and contracting end of the second piezo element;
The load beam has an end opposite to the end in contact with the pivot plate so as to change the pitch angle of the slider by changing the contact position of the flexure of the pivot by expansion and contraction of the first piezo element. Fixed,
The load beam has an end opposite to the end in contact with the pivot plate so as to change the roll angle of the slider by changing the contact position of the flexure of the pivot by expansion and contraction of the second piezo element. To fix,
A method of supporting a magnetic head. A magnetic disk device having a magnetic head support mechanism for supporting a slider mounted with a magnetic head on a load beam via a flexure,
The load beam has a pivot position control mechanism including a pivot plate and first and second piezoelectric elements,
The pivot plate has a pivot formed on the pivot plate in contact with the flexure, and one end portion in the track direction of the pivot plate is in contact with an end portion of the first piezoelectric element that expands and contracts. One end in the seek direction is in contact with the expanding and contracting end of the second piezo element,
The first piezo element is opposed to an end in contact with the pivot plate so as to change a pitch angle of the slider by changing a contact position of the flexure of the pivot by expansion and contraction of the first piezo element. The end to be fixed to the load beam,
The second piezo element is opposed to an end in contact with the pivot plate so that the roll angle of the slider is changed by changing the contact position of the flexure of the pivot by expansion and contraction of the second piezo element. The end to be fixed to the load beam,
A magnetic disk device characterized by the above.

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