JPH04258854A - Disk device - Google Patents

Abstract

PURPOSE:To suppress rotating force to work upon a bearing part of an arm and to make the rotating force a flat characteristic which is unchangable according to a position of a head by disposing an elastic deformable part of a flexible printed board in an approximately S-shape. CONSTITUTION:The flexible printed board 16 for transmitting a signal to a magnetic head 5 and a voice-coil motor 8 is fitted with its one end to a frame 1 by a screw 10, while its part 16b bent at 90 deg. in the vertical direction to the bottom surface of the frame 1 is formed, and is fixed to the frame 1 by an adhesive means. Then, the elastic deformable part 16a is formed in an approximately S-shape. Consequently, when the voice-coil motor 8 is driven, and the head 5 is positioned into a data track, the rotating force around a center P of a pivot shaft assembly 1 becomes a flat characteristic without changing in accordance with the head position, and the rotating force can apparently be eliminated, and then the servo performance can remarkably be enhanced.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a disk device.
More specifically, the present invention relates to an arrangement structure of a flexible printed circuit board that transmits a signal to an actuator means configured at one end of a swing arm.

0002

2. Description of the Related Art For example, FIG.
There is a disk device like the one shown in . FIG. 4 is a plan view of a conventional disk device. In this disk device, a magnetic disk 2 having a magnetic recording layer formed thereon is fixed to a spindle motor (not shown) attached to a frame 1 with a clamp screw 3 via a clamper 4. A magnetic head 5 for recording and reproducing information is disposed facing the magnetic disk 2, and a swing arm 6 on which the magnetic head 5 is mounted is arranged such that the magnetic head 5 is arranged in a radial direction of the magnetic disk 2. to a position that can be moved freely,
It is rotatably supported by a pivot shaft assembly 7. A coil 8a, which is a part of the voice coil motor 8 for moving and positioning the magnetic head 5, is a portion of the swing arm 6 that extends to the opposite side of the magnetic head 5 with respect to the pivot shaft assembly 7. is installed on. Further, a stopper 1 is provided on the voice coil motor 8 to restrict the rotation range of the swing arm 6.
4 is installed. The flexible printed circuit board 9 that transmits signals to the magnetic head 5 and the voice coil motor 8 has one end attached to the frame 1 with a screw 10 and a portion 9b bent at 90 degrees perpendicularly to the bottom surface of the frame 1. form frame 1
It is fixed to the more protruding rib 1a by adhesive means such as double-sided tape. Furthermore, the other end 9c which is the extension part
is fixed to the swing arm 6. When the magnetic disk 2 is stopped, the magnetic head 5 and the magnetic disk 2 may stick together or receive an external impact, which may cause dents on the magnetic disk 2. The swing arm 6 is held by a holding mechanism 12 made up of a cam. The housing for accommodating the magnetic disk 2, magnetic head 5, swing arm 6, voice coil motor 8, etc. in a clean space is made up of the frame 1 and the cover 13, and there is no gap between the mating surfaces of these. A sealing member (not shown) is interposed to maintain a clean space.

In the magnetic disk device configured as described above, when the magnetic disk 2 is rotated at about 3000 rpm, an air flow is generated on the surface of the magnetic disk. In this state, when the disk reaches a predetermined rotational speed, the voice coil motor 8 is driven to move the swing arm 6 on which the magnetic head 5 is mounted to the holding mechanism 1.
2, the magnetic head 5 can be moved onto the data area of the magnetic disk. The magnetic head 5 is pressed against the magnetic disk 2 by the suspension 15 attached to the swing arm, but floats above the magnetic disk 2 because an air film is formed by the air flow. In this state, the voice coil motor 8 is driven and controlled to rotate the swing arm 6 in the radial direction of the magnetic disk 2, thereby positioning the magnetic head 5 on a target track within the data area of the magnetic disk 2. Record and play data.

[0004] An amplifier 13 for amplifying the minute signal read by the magnetic head 5 is mounted on the flexible printed circuit board 9 near a portion where it is fixed to the frame 1. The amplifier 13 is generally placed in the clean space in order to prevent the minute signal from being affected by external noise as much as possible. Further, the flexible printed circuit board 9 is connected to the rotating swing arm 6,
Since it is fixed to the frame 1 which is a rigid body, the elastic deformation part 9 can be elastically deformed as the swing arm 6 swings.
By forming a, it is possible to transmit an electric signal to the rotating swing arm.

[0005]

By the way, in the conventional magnetic disk device, when the magnetic head 5 moves within the data area of the magnetic disk 2, the elastic deformation portion of the flexible printed circuit board 9 is caused to change depending on the position of the magnetic head 5. The shape of the magnetic head 9a changed, and the rotational force acting around the pivot shaft assembly 7 of the swing arm 6 varied as shown in FIG. 5 depending on the position of the magnetic head 5. FIG. 5 is a diagram of the rotational force acting around the pivot shaft assembly 7 due to the flexible printed circuit board 9 of a conventional disk device. Therefore, when configuring a servo system that positions the magnetic head 5 to a data track on a magnetic disk, the rotational force acting around the pivot shaft assembly 7 due to the shape change of the elastic deformation portion 9a acts as an external force, and the target track is tracked. This causes a decline in positioning performance and requires an external force correction means such as feedforward in the control system, making the magnetic disk drive complicated.

[0006]

[Means for Solving the Problems] As a means for solving the problems of the prior art, the present invention includes a frame on which a rotatably supported disk is arranged, a head for recording and reproducing data on the disk, and a head for recording and reproducing data on the disk. a swing arm having a support portion supported movably in a direction and rotatably supported; an actuator means configured at one end of the swing arm for moving and positioning the head; and at least a signal to the actuator means. The flexible printed circuit board has one end disposed on a part of the swing arm, the other end disposed on a part of the frame, and the flexible printed circuit board is disposed on a part of the swing arm. In the disk device having a portion that can be elastically deformed as the swing arm rotates, the elastically deformable portion is arranged to form a substantially S-shape.

Further, in such a configuration, the substantially S-shape is formed by two continuous curves consisting of a concave portion and a convex portion, and the curve of the concave portion and the curve of the concave portion are formed within a range in which the head can rotate. The arrangement is such that there is a portion where the shapes of the curved lines of the convex portions are symmetrical and substantially equal, and the flexible printed circuit board is arranged in the elastically deformable portion in the arrangement portion of the flexible printed circuit board disposed on the swing arm. An arrangement in which an extension line of the extending portion substantially intersects with the supporting portion, and an extending portion of the flexible printed circuit board extending to the elastically deformable portion,
The support portion may be arranged to extend at an angle of 45° or more with respect to an axis connecting the head.

[0008]

[Operation] As in the above means, by arranging the elastically deformable portion of the flexible printed circuit board in a substantially S-shape, the rotational force acting on the support portion of the swing arm due to the elastically deformable portion of the flexible printed circuit board is transferred to the position of the head. It becomes possible to obtain a characteristic that acts as a substantially flat rotational force that does not change, and it is also possible to suppress or eliminate the rotational force around the support portion. Further, in order to utilize this characteristic more effectively, the flexible printed circuit board is arranged such that an extension line of an extension portion extending to the elastically deformable portion substantially intersects with the support portion in the arrangement portion of the flexible printed circuit board. This makes it possible to minimize the rotational force around the support due to the elastic force. Further, in order to configure such an extension part, there are layout constraints, so the flexible printed circuit board should be arranged at an angle of 45 degrees or more with respect to the axis connecting the support part of the swing arm and the head. By configuring the flexible printed circuit board to extend from the flexible printed circuit board, it is possible to arrange the flexible printed circuit board as described above in a small space.

[0009]

[Embodiments] Hereinafter, embodiments of the present invention will be explained with reference to the drawings. FIG. 1 is a plan view of an embodiment of the disk device of the present invention, and FIG. 2 is an enlarged view of FIG. 1 for explaining the operation of the swing arm and flexible printed circuit board of the present invention. Note that since many parts of the overall configuration of the disk device of this embodiment are the same as those of the prior art described above, the same members will be designated by the same reference numerals.

In this disk device, a magnetic disk 2 having a magnetic recording layer formed thereon is fixed to a spindle motor (not shown) attached to a frame 1 with a clamp screw 3 via a clamper 4. The magnetic disk 2 has a magnetic head 5 for recording and reproducing information.
are arranged facing each other, and a swing arm 17 on which the magnetic head 5 is mounted is rotatably supported by a pivot shaft assembly 7 at a position where the magnetic head 5 can freely move in the radial direction of the magnetic disk 2. has been done. A coil 8a, which is a part of the voice coil motor 8 for moving and positioning the magnetic head 5, is a portion of the swing arm 17 that extends to the opposite side of the magnetic head 5 with respect to the pivot shaft assembly 7. is installed on. Further, a stopper 14 is attached to the voice coil motor 8 in order to restrict the range of rotation of the swing arm 6. The flexible printed circuit board 16 that transmits signals to the magnetic head 5 and voice coil motor 8 includes:
One end is attached to the frame 1 with a screw 10, and is 90° perpendicular to the bottom surface of the frame 1.
A bent portion 16b is formed and is fixed to the rib 1a protruding from the frame 1 by adhesive means such as double-sided tape. Further, the other end 16c, which is an extension thereof, is
It is fixed to the swing arm 6. When the magnetic disk 2 is stopped, the magnetic head 5 and the magnetic disk 2 may stick together or receive an external impact, which may cause dents on the magnetic disk 2. The swing arm 6 is held by a holding mechanism 12 made up of a cam. The housing for accommodating the magnetic disk 2, magnetic head 5, swing arm 6, voice coil motor 8, etc. in a clean space is made up of the frame 1 and the cover 13, and there is no gap between the mating surfaces of these. A sealing member (not shown) is interposed to maintain a clean space.

In the magnetic disk device configured as described above, when the magnetic disk 2 is rotated at about 3000 rpm, an air flow is generated on the surface of the magnetic disk 2. In this state, when the magnetic disk 2 reaches a predetermined rotational speed, the voice coil motor 8 is driven and the swing arm 6 on which the magnetic head 5 is mounted is released from the holding mechanism 12. Accordingly, the magnetic head 5 can be moved onto the data area of the magnetic disk. The magnetic head 5 is pressed against the magnetic disk 2 by the suspension 15 attached to the swing arm 17, but floats above the magnetic disk 2 because an air film is formed by the air flow. In this state, the voice coil motor 8 is driven and controlled to swing the swing arm 17 in the radial direction of the magnetic disk 2, thereby positioning the magnetic head 5 on a target track within the data area of the magnetic disk 2. Record and play data.

The flexible printed circuit board 16 includes:
An amplifier 13 for amplifying minute signals read from the magnetic head 5 is mounted near the fixed portion to the frame 1. The amplifier is generally placed in the clean space in order to prevent the minute signal from being affected by external noise as much as possible. Further, since the flexible printed circuit board is fixed to the swing arm 17 that rotates and the frame 1 that is a rigid body, the elastic deformation section 1 that can be elastically deformed as the swing arm 17 swings.
6a makes it possible to transmit electrical signals to the rotating swing arm 17.

The swing arm 17 will be described below with reference to FIG.
Now, the structure and operating characteristics of the flexible printed circuit board 16 will be described. In FIG. 2, axis A indicates the position where the magnetic head 5 is at the innermost periphery of the data track of the magnetic disk 2, and axis B indicates the position where the swing arm 17 is held by the holding mechanism 12. The rotation range of the swing arm 17 is regulated by a stopper 14 provided on the voice coil motor 8, but when the voice coil motor 8 is servo controlled, the range between the axis A and B is actually It becomes the rotation range. A flexible printed circuit board fixing part 17a integrally formed with the swing arm 17 fixes one end 16c of the elastically deformable part 16a of the flexible printed circuit board 16, and an extension line C of the fixing part 16c is connected to the pivot. The mounting surface intersects with the center P of the shaft assembly 7, and the angle θ between the extension line C and the axis A is 45° or more. At the position A or B, the elastically deformable portion 16a of the flexible printed circuit board 16 forms a substantially S-shape. That is, the elastically deformable portion 16a always forms a substantially S-shape within the range in which the swing arm rotates. Especially B
At the position, the shapes of the concave curve D and the convex curve E constituting the S-shape are symmetrical and equal. By the way, the elastic deformation portion 16a
had a flat band shape before being fixed to the swing arm 17 and the rib 1a protruding from the frame 1, so after being fixed to the S-shape, it tries to return to the shape before deformation. A restoring force acts, and this restoring force becomes a rotational force about the center P of the pivot shaft assembly 7. The rotational force acts as an external force when configuring a servo system that drives and controls the voice coil motor 8 and controls the positioning of the magnetic head 5 on the data track of the magnetic disk 2, so it is desirable that it be as small as possible. . Figure 3
is a flexible printed circuit board 1 of a disk device of the present invention.
6 is a diagram of the rotational force acting around the pivot shaft assembly 7 according to FIG. In FIG. 3, flexible printed circuit board 1
It can be seen that the rotational force around point P due to 6 is smaller than that of the conventional disk device, and has a substantially flat characteristic in which the magnitude and direction are the same regardless of the position of the magnetic head 5. This is achieved by forming the elastically deformable portion 16a into a substantially S-shape, thereby forming a concave curve and a convex curve. As described above, by forming the elastic deformation portion 16a into a substantially S-shape, the flexible printed circuit board 1
The rotational force around point P caused by the elastic deformation portion 16a of No. 6 can be suppressed more than in conventional disk devices. Further, the substantially flat characteristic as shown in FIG. 3 is extremely effective for correction by configuring a simple correction means. For example, by driving the voice coil motor 8 to generate an offset rotational force in the opposite direction to the rotational force exerted by the flexible printed circuit board 16, the rotational force exerted by the flexible printed circuit board 16 can be apparently canceled out. Alternatively, the offset rotational force may be applied mechanically, for example, by a spring or the like.

[0014]

[Effects of the Invention] As described above, by arranging the elastically deformable portion of the flexible printed circuit board in a substantially S-shape, the rotational force exerted on the swing arm support portion by the elastically deformable portion is suppressed. becomes possible. In particular, according to the present invention, as described above, the rotational force exerted on the swing arm support part by the elastically deformable part of the flexible printed circuit board has a substantially flat characteristic that does not change depending on the position of the head, so that a simple correction means can be used. With this configuration, it becomes possible to apparently eliminate the rotational force acting on the support portion of the swing arm. In other words, when configuring a servo system for positioning a head to a data track on a disk, the servo performance such as head positioning accuracy and positioning speed can be significantly improved.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an embodiment of a disk device of the present invention.

FIG. 2 is an enlarged view of FIG. 1 for explaining the operation of the swing arm and flexible printed circuit board of the present invention.

FIG. 3 is a diagram of the rotational force acting around the pivot shaft assembly 7 due to the flexible printed circuit board 16 of the disk device of the present invention.

FIG. 4 is a plan view of a conventional disk device.

FIG. 5 is a diagram of the rotational force acting around the pivot shaft assembly 7 due to the flexible printed circuit board 9 of a conventional disk device.

[Explanation of symbols]

1... Frame 2... Disc 5... Head 7... Pivot shaft assembly 8...
...Voice coil motor 16...Flexible printed circuit board 16a.
...Elastic deformation part 17 ... Swing arm

Claims (4)

[Claims] Claims: 1. A frame on which a rotatably supported disk is disposed; a head for recording and reproducing data on the disk; a swing arm having a supporting portion; actuator means configured at one end of the swing arm for moving and positioning the head; and a flexible printed circuit board for transmitting a signal to at least the actuator means. , the flexible printed circuit board has one end disposed on a part of the swing arm, the other end disposed on a part of the frame, and has a portion that can be elastically deformed as the swing arm rotates. A disk device, wherein the elastically deformable portion is arranged to form a substantially S-shape. 2. The substantially S-shape is composed of a concave portion and a convex portion.
A claim characterized in that, within a range in which the head can rotate, there is a portion formed by two continuous curves in which the curves of the concave portion and the curve of the convex portion are symmetrical and substantially equal in shape. Item 1. Disk device according to item 1. 3. In the arrangement portion of the flexible printed circuit board disposed on the swing arm, an extension line of the extending portion of the flexible printed circuit board extending to the elastically deformable portion is approximately aligned with the center of the support portion. 2. The disk device according to claim 1, wherein the disk devices intersect. 4. In the arrangement portion of the flexible printed circuit board disposed on the swing arm, the extending portion of the flexible printed circuit board extending to the elastically deformable portion is aligned with an axis connecting the support portion and the head. against 4
4. The disk device according to claim 3, wherein the disk device is arranged so as to extend at an angle of 5 degrees or more.