JP2003228935A - Suspension and magnetic disk device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a suspension which enables stable reading/writing operation against an impact and can be mounted with a head arm with a size nearly equal to that of a conventional suspension and a magnetic disk device using the same. <P>SOLUTION: The suspension is constituted including a load beam 1 which supports a slider mounted with a magnetic head, a spring part 5 which is coupled with a rear end part of the load beam, an arm 6 composed of a plate- shaped member coupled with the rear end part of the spring part 5, and a counter weight 7 which is coupled with the load beam and has its center of gravity more on the arm side than the coupling part; and the counter weight 7 is made of a plate-shaped member and extends from the coupling part for the load beam 1 along the width of the suspension in parallel to the plate surface of the arm 6 and also extends from a projection position toward the arm 6 along the length of the suspension. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension for supporting a magnetic head and a magnetic disk device, and more particularly to improvement of impact resistance of the magnetic disk device.

[0002]

2. Description of the Related Art Since a magnetic disk device is widely used in mobile devices such as laptop computers, it is possible to operate normally even when a shock is applied such as when it is dropped so that recorded information is not destroyed. There is a strong demand for improved impact resistance. Regarding the improvement of impact resistance performance, see
There is one provided with a counter weight shown in Japanese Patent Publication No. 11-39808.

[0003]

In a slider equipped with a magnetic head, the suspension, which is an elastic support member, compresses the force (pressing force) that pushes the slider toward the disk and the air that flows between the slider and the disk. By balancing the pressure generated in the disk, it floats above the disk with a very small gap of several tens of nanometers. However, when an external shock is applied to the magnetic disk device, the balance between the pressing force and the pressure may be lost, and the slider may not be able to normally fly.

Specifically, when an inertial force is generated in the suspension in a direction away from the disk due to a shock, the pressing force of the suspension is reduced and the flying height of the slider is increased. As the flying height increases,
Since this is equivalent to increasing the magnetic distance between the magnetic head and the recording medium on the disk, normal reading and writing becomes impossible when the amount of change in the flying height is large.

When a larger inertial force is generated, a phenomenon called head jump occurs in which the slider jumps up from the disk. When a head jump occurs, the spring force of the suspension strikes the slider against the disk, causing the slider and disk to collide. Then, there arises a problem that the recorded information is destroyed on the disk, or the smoothness of the disk is impaired by a dent and the slider cannot normally fly.

Further, the collision causes a problem that the magnetic head itself is damaged and the read / write operation cannot be performed.

In the example of Japanese Patent Laid-Open No. 11-39808, a counter weight is provided to make head jump less likely to occur. However, in an actual magnetic disk device, the distance between the stacked disks and the distance between the disks and the cover and the housing are very small. Therefore, as disclosed in JP-A-11-39808, the head arm There is no space for vertically installing the counterweight, and it is difficult to mount the head arm having the counterweight on the magnetic disk device.

An object of the present invention is to provide a suspension in which a read / write operation can be stably performed even when a shock is applied, and a head arm can be mounted in the same size (space) as a conventional suspension, and a magnetic field using the suspension. It is to provide a disk device.

[0009]

[Means for Solving the Problems] In order to perform a stable read / write operation even when a shock is applied, a counterweight that cancels the inertial force due to the shock is required. The inventors studied how to mount a suspension equipped with this counterweight in the same size (space) as the conventional suspension, and as a result, the counterweight was placed outside the width direction of the arm and load beam. We paid attention to the fact that the counterweight can be installed without increasing the thickness of the suspension by overhanging.

That is, in order to achieve the above object,
The counterweight made of a plate-shaped member is projected outward from the load beam in the width direction, and is extended from the load beam in the arm direction in parallel with the arm plate surface. The counterweight need not be a plate-like member as long as it is within the thickness region defined by the uppermost part and the lowermost part of the arm and the load beam.

The center of gravity of the counterweight is located on the arm side of the connection point between the counterweight and the load beam, so that upon impact, the counterweight acts on the head in a direction opposite to the force acting on the magnetic head due to the impact. To do. For this reason, it becomes easy to perform stable read / write operations even when a shock is applied to the device, and damage to the disk and magnetic head is less likely to occur. Further, since the counterweight is arranged outside the width direction of the arm and the load beam and in parallel with the arm and the disk surface, the thickness of the arm portion is the same as that of the conventional magnetic disk device and is the same as the conventional one. Since it can be mounted in a space, a magnetic disk device having high impact resistance can be realized without increasing the magnetic disk interval.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 1 is a perspective view showing a first embodiment of a magnetic disk device to which the present invention is applied. Figure 2
2 is a perspective view of the suspension of the magnetic disk device shown in FIG. 1, FIG. 3 is a side view of the suspension shown in FIG. 2, and FIG. 4 is a rear view of the suspension shown in FIG. In the magnetic disk device shown in FIG. 1, a plurality of magnetic disks 4 are stacked and fixed to a common rotating shaft, a magnetic disk driving means for rotating the rotating shaft, and the corresponding magnetic disks 4 respectively.
A plurality of sliders (not shown) equipped with magnetic heads for writing data to or reading data from the magnetic disk 4, and a plurality of suspensions that respectively support the plurality of sliders and are mounted on a common shaft. A suspension driving means 20 which is a positioning means for driving the plurality of suspensions to move the slider in the radial direction of the magnetic disk 4 and position it at a desired position.

As shown in FIGS. 2 to 4, the suspension includes a plate-shaped arm 6 having an opening at the rear end for mounting on the common shaft, and an end portion of the arm 6 having no opening. A plate-shaped spring portion 5 in which a lower surface of a rear end portion is superposed on the upper surface in the figure and combined, a load beam 1 of the same plate shape integrally formed by being connected to the front end of the spring portion 5, and the load beam 1 A counter plate 7 of the same plate shape that is fixed by spot welding or the like on the side (rear side) on which the arm 1 is overlapped.
And a flexure 2 mounted on the rear surface (hereinafter, also referred to as a lower surface) of the tip portion of the load beam 1, and a slider 3 having the magnetic head mounted thereon is attached to the flexure 2. The arm 6 includes a load beam 1, a spring portion 5, a counterweight 7, and a slider 3.
I support you.

The spring portion 5 is fixed to the arm 6 by welding or the like, and the load beam 1 is formed on the tip side of the portion fixed to the arm 6. The load beam 1 is a rigid body portion for applying a predetermined slider load to the slider, and the spring portion 5 generates the slider load and applies the generated slider load to the slider 3 via the load beam 1.

The counterweight 7 is divided into two parts that sandwich the longitudinal axis of the suspension and are symmetrical with respect to a plane that includes the longitudinal axis and is perpendicular to the plate surface of the arm 6, and the tip portion thereof is loaded. The spring portion 5 of the beam 1
The rear end portion of the counterweight 7 is fixed to the rear surface near the connecting portion with the, and the rear end portion of the counterweight 7 extends toward the arm 6 side from the rear end of the spring portion 5. The counterweight 7 extends from the portion fixed to the load beam 1 to the outside of the load beam 1 on both sides in the width direction of the suspension, and then at a position apart from the width direction outside of the load beam 1 rather than the rear end of the spring portion 5. It is extended so that the rear end is located on the 6 side, that is, the center of gravity is located on the arm 6 side with respect to the spring portion 5. In other words, the rear end of the counterweight 7 is the load beam 1
Or even if it vibrates in a direction orthogonal to the plate surface of the arm 6,
The counterweight 7 is shaped so as not to come into contact with the load beam 1 or the arm 6. In other words, the counterweight 7 is a cantilever having the joint with the load beam 1 as the fulcrum (fixed point) and the end on the arm side as the free end, and the force applied to its center of gravity is A rotational moment is generated at the joint part of.

When the counterweight 7 is projected on a plane parallel to the plate surface of the arm 6, the member portion connected to the load beam 1 is the bottom side, and the portion extending laterally of the arm 6 is the vertical side. It has an L shape.

The load beam 1 and the spring portion 5 have a thickness of 40 to 7
It is made of a stainless thin plate of about 0 μm, and in the part of the load beam 1 that needs rigidity, along the side surface in the width direction,
Rigidity is ensured by providing flanges 8 on both sides, which are raised upward in the drawing by bending.

The suspension is constructed and arranged so that the slider 3 flies above the recording surface of the magnetic disk 4 at intervals of several tens of nm when the magnetic disk 4 is rotating.

The principle of the present invention will be described with reference to FIGS. 5 and 6, the load beam 1 and the counterweight 7 are rigid bodies, and the spring portion 5 is modeled and shown as a spring element. Normally, when inertial force due to impact (inertial force in the direction of moving the slider away from the magnetic disk) is applied to the suspension, an inertial force as shown in FIG. Since the fulcrum of the load beam 1 is the position of the slider 3 and the spring portion 5, the load beam 1
The inertial force generated in 1 is considered as a component force acting on the slider 3 and the spring portion 5.

When a component force as shown in FIG. 5 is applied to the slider 3, since the slider 3 is in the direction of separating from the disk, the flying height of the slider 3 becomes larger than the specified amount, and normal read / write operation cannot be performed. When the impact input is further increased and the component force acting on the slider 3 is larger than the pressing force on the slider 3, the slider 3 jumps from the disk surface (head jump) and then the spring force of the spring portion 5 causes the slider 3 to move. 3 is struck on the disk 4, the disk 4 and the slider 3 are damaged, and normal operation cannot be performed even after the impact input is completed.

On the other hand, when the counterweight 7 is provided as shown in FIG. 6, an inertial force is also generated by the impact on the counterweight 7, but the counterweight 7 is the fulcrum of the arm 6 side of the load beam 1. Since the center of gravity is provided closer to the arm 6 side than the end portion (spring portion 5), the component component of the inertial force of the counterweight 7 acting on the slider 3 acts on the load beam 1 acting on the slider 3. It is in the opposite direction to the component of inertial force. That is,
The component force of the inertial force of the counterweight 7 cancels the component force of the inertial force of the load beam 1 at the position of the slider 3. Therefore, the flying height variation of the slider 3 and head jump are less likely to occur even during impact, and the impact resistance performance of the device can be improved.

Further, as shown in FIGS. 2 to 4, since the counterweight 7 is extended in the width direction of the suspension and then extended in the direction of the arm 6, the counterweight 7 can be arranged in substantially the same plane as the arm 6. . In this embodiment, since the upper surface of the counterweight 7 is in contact with the rear surface of the load beam 1, the upper surface of the counterweight 7 and the upper surface of the arm 6 are substantially flush with each other. Therefore, as shown in the AA cross section of FIG. 2, if the thickness of the counterweight 7 is less than or equal to the thickness of the arm 6, there is almost no increase in the thickness H of the suspension due to mounting the counterweight 7. The magnetic disk device can be configured with the same mounting dimensions (interval between magnetic disks) as the conventional one.

Although the counterweight 7 is formed of a plate-shaped member in the present embodiment, the counterweight 7 is mounted on the lowermost portion of the arm 6 and the load beam 1 in the mounted state.
The plate-shaped member is not necessarily required as long as it is within the thickness region defined by the uppermost part of the.

Further, in the present embodiment, the center of gravity of the counterweight 7 is located on the arm 6 side and on the outer side in the width direction of the arm 6 with respect to the spring portion 5, but as will be understood from the description of FIG. It suffices if it is on the arm 6 side with respect to the connecting portion with 1. (Second Embodiment) FIG. 7 shows a second embodiment of the present invention.
Will be described with reference to. FIG. 7 is a perspective view showing a second embodiment of the present invention. The present embodiment is different from the first embodiment in that the peripheral portion of the counterweight 7 is bent and a bent portion 9 is provided. Since other configurations are the same as those of the first embodiment, the same reference numerals are given and the description thereof will be omitted.

In the first embodiment, the counterweight 7 vibrates due to the positioning operation, the impact input, and the external exciting force applied to the magnetic disk device, and the flying height of the slider 3 fluctuates and the head shifts in the positioning direction. This may cause a malfunction in the data read / write operation. In the present embodiment, by bending the side surface of the counterweight 7 and providing the bent portion 9, the rigidity of the counterweight 7 is enhanced and vibration of the counterweight 7 can be suppressed. (Third Embodiment) A third embodiment of the present invention will be described with reference to FIGS. 8 is a perspective view showing a third embodiment of the present invention, and FIG. 9 is a sectional view taken along the line AA 'of FIG. The present embodiment differs from the first embodiment in that the counterweight 7 is provided with ribs 10. Since other configurations are the same as those of the first embodiment, the same reference numerals are given and the description thereof will be omitted.

When the counterweight 7 is bent as in the second embodiment shown in FIG. 7, it is difficult to bend the counterweight 7 at a portion where the end portion of the counterweight 7 is not a straight line. In addition, the rigidity of the counterweight 7 may decrease. In the present embodiment, by providing the rib 10 as shown in FIGS. 8 and 9, the rigidity of the counterweight 7 can be increased without being affected by the shape of the counterweight 7. (Fourth Embodiment) FIG. 1 shows a fourth embodiment of the present invention.
This will be described with reference to 0. FIG. 10 is a rear view showing the fourth embodiment of the present invention. The present embodiment is different from the first embodiment in that the shape of the flexure 2 which is a component of the conventional suspension is changed and the counterweight 7 is provided. Since other configurations are the same as those of the first embodiment, the same reference numerals are given and the description thereof will be omitted.

In the first to third embodiments, the counterweight 7 is formed by adding another component to the component of the conventional suspension. In the present embodiment, the shape of the flexure 2 that is a conventional suspension component is changed so that the flexure 2 and the counterweight 7 are combined. In the present embodiment, the counterweight 7
The impact force applied to the slider 3 is applied to the flexure 2 as a moment without passing through the load beam 1, and the slider 3
Acts to counteract the upward force applied to.

According to this embodiment, an increase in the number of parts can be avoided and an increase in cost can be suppressed. Also in this embodiment, it is effective to increase the rigidity of the counterweight 7 by providing the bent portion 9 as shown in FIG. 7 or the rib 10 as shown in FIG. (Fifth Embodiment) FIG. 1 shows a fifth embodiment of the present invention.
1 and FIG. 12 will be described. FIG. 11 shows the fifth aspect of the present invention.
12 is a perspective view showing the embodiment of FIG. 12, and FIG. 12 is a plan view showing the rear surface of the suspension shown in FIG. The present embodiment is different from the first embodiment in that a relatively thick stainless steel plate having a thickness of about 100 μm is used for the load beam 1 and the counterweight 7 is formed directly from the end face of the load beam 1. 4 different from load beam 1
The point is that it is connected to the arm 6 via the spring portion 5 formed of a thin plate of about 0 μm. Since other configurations are the same as those of the first embodiment, the same reference numerals are given and the description thereof will be omitted.

In each of the above embodiments, the load beam 1 and the spring portion 5 are made of a continuous member. In the present embodiment, a relatively thick stainless plate having a thickness of about 100 μm is used for the load beam 1, and the end weight of the load beam 1 is extended to form the counterweight 7. The spring portion 5 is separately formed from a thin plate of about 40 μm, and the upper surface of its rear end is fixed to the rear surface of the arm 6, and the rear surface of the load beam 1 is fixed to the upper surface of its front end by welding or the like. That is,
The positions of the lower surface of the load beam 1 and the lower surface of the counterweight 7 are the positions of the extension surfaces of the back surface of the arm 6, and the thickness of the load beam 1 and the counterweight 7 are included in the thickness range of the arm 6.

As a result, the torsional rigidity of the load beam 1 portion can be increased and the head positioning error due to the vibration of the load beam 1 can be reduced as compared with the above-described respective embodiments. At the same time, the upper surface position of the load beam 1 becomes relatively lower than the upper surface position of the arm 6,
Since the thickness of the suspension becomes smaller, it becomes easier to mount the suspension between the disks even if the disk spacing becomes smaller than at present. As a result, it becomes possible to mount many disks to increase the recording capacity of the magnetic disk device and to reduce the height of the entire magnetic disk device.

[0031]

According to the present invention, the inertial force generated in the counterweight acts on the slider 3 in the direction opposite to the inertial force generated in the load beam, so that stable read / write operations can be performed even when a shock is applied. Moreover, since the counterweight is arranged in the thickness region determined by the arm and the load beam, it is possible to provide a suspension that can be mounted with the same size as a conventional suspension and a magnetic disk device using the suspension.

[Brief description of drawings]

FIG. 1 is a perspective view of a magnetic disk device according to a first embodiment of this invention.

FIG. 2 is a perspective view of the suspension according to the first embodiment of the present invention.

FIG. 3 is a side view of the suspension according to the first embodiment of the present invention.

FIG. 4 is a rear view of the suspension according to the first embodiment of this invention.

FIG. 5 is a schematic diagram of a rigid body model of a conventional suspension.

FIG. 6 is a schematic diagram of a rigid body model of the suspension of the present invention.

FIG. 7 is a perspective view of a suspension according to a second embodiment of the present invention.

FIG. 8 is a perspective view of a suspension according to a third embodiment of the present invention.

FIG. 9 is a sectional view of a suspension according to a third embodiment of the present invention.

FIG. 10 is a rear view of the suspension according to the fourth embodiment of the present invention.

FIG. 11 is a perspective view of a suspension according to a fifth embodiment of the present invention.

FIG. 12 is a rear view of the suspension according to the fifth embodiment of the present invention.

[Explanation of symbols] 1 load beam 2 flexure 3 slider 4 discs 5 Spring 6 arms, 7 counterweight 8 flange 9 Bending section 10 ribs

Continued front page    (72) Inventor Keiko Watanabe             502 Kintatemachi, Tsuchiura City, Ibaraki Japan             Tate Seisakusho Mechanical Research Center (72) Inventor Yasuhiro Matsuda             502 Kintatemachi, Tsuchiura City, Ibaraki Japan             Tate Seisakusho Mechanical Research Center F-term (reference) 5D059 AA01 BA01 CA21 DA26 EA08

Claims (7)

[Claims] 1. A load beam, which is a rigid portion for supporting a slider having a magnetic head mounted on its lower surface through a flexure and applying a predetermined slider load to the slider, and a rear end portion of the load beam. A spring portion that is coupled to generate the slider load, an arm that is coupled to a rear end side of the spring portion and that is composed of a plate-shaped member that supports the load beam and the spring portion, and a center of gravity that is coupled to the load beam. A counterweight on the arm side of the load beam coupling portion, wherein the counterweight is a plate-shaped member, and is parallel to the arm plate surface from the load beam coupling portion. The suspension beam is extended to the outside of the load beam and the arm is extended from the extended position to the suspension longitudinal direction. Suspension characterized by extending to the side. 2. A load beam, which is a rigid portion for supporting a slider having a magnetic head mounted on the lower surface of the front end through a flexure and applying a predetermined slider load to the slider, and a rear end of the load beam. A spring portion that is coupled to generate the slider load, an arm that is coupled to a rear end side of the spring portion and that is composed of a plate-shaped member that supports the load beam and the spring portion, and a center of gravity that is coupled to the load beam. And a counterweight on the arm side of the joint with the load beam, wherein the counterweight has a position and shape such that the center of gravity of the counterweight is on the outside in the width direction of the arm. Is located between the load beam and the top and bottom of the arm. 3. The suspension according to claim 1, wherein the counterweight is a cantilever whose front end is supported by a load arm and whose other end is a free end located outside in the width direction of the arm. Suspension characterized by that. 4. The suspension according to claim 1, wherein the counterweight is a member portion coupled to the load beam when projected on a plane parallel to a plane of the arm. A suspension having an L-shape having a bottom as a base and a portion extending laterally of the arm as a vertical side. 5. The suspension according to claim 1, wherein the counterweight is provided on both sides in a width direction of a center line in a longitudinal direction of the suspension.
A suspension characterized in that the arm is formed symmetrically with respect to a plane orthogonal to a plate surface including the center line in the longitudinal direction. 6. A load beam, which is a rigid portion for supporting a slider having a magnetic head mounted on its lower surface through a flexure and applying a predetermined slider load to the slider, and a rear end portion of the load beam. A spring portion that is coupled to generate the slider load, is coupled to a rear end side of the spring portion, is connected to the load beam and an arm made of a plate-shaped member that supports the spring portion, is coupled to the flexure, and has a center of gravity. In a suspension including a counterweight on the arm side of a connecting portion with a flexure, the counterweight includes a plate-shaped member,
A suspension characterized in that it extends from the joint with the flexure to the outside of the load beam in the suspension width direction in parallel to the plate surface of the arm, and extends from the extension position to the arm side in the suspension longitudinal direction. 7. A magnetic disk on which information is recorded, and magnetic disk drive means for rotating and driving the magnetic disk,
A slider equipped with a magnetic head for reading information recorded on the magnetic disk and / or writing information on the magnetic disk, a suspension for supporting the slider, and a magnetic disk for driving the suspension. 7. A magnetic disk device comprising a positioning means for positioning the head at a desired position on the recording surface of the magnetic disk, wherein the suspension is the suspension according to any one of claims 1 to 6. A magnetic disk device characterized by being present.