JPH0636252A - Actuator structure of magnetic disk device - Google Patents

Abstract

PURPOSE:To improve the positioning accuracy of an actuator while thinning and reducing a magnetic disk device for the actuator structure of the magnetic recording disk with a structure where the magnetic head for servo is laid out along with the magnetic head for recording/reproduction. CONSTITUTION:Assuming a virtual line 25 connecting the rotation center of an arm 4 and the head centers of magnetic heads 8 and 9, a signal line 14 for read/write connecting the head 8 for read/write and a FPC 13 and ICs 18 and 19 for read/write are laid out at one part of an arm 4 which is separated from the virtual line 25. A signal line 15 for servo connecting the head 9 for servo and the FPC 13 and an IC 20 for servo are laid out at the other part of the arm 4 which is separated from the virtual line 25.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an actuator structure of a magnetic disk device, and more particularly to an actuator structure of a magnetic disk device having a structure in which a servo magnetic head is arranged together with a recording / reproducing magnetic head.

With the recent increase in speed, capacity, or downsizing of computer systems, the magnetic disk device, which is an external storage device, is becoming lighter, thinner, and smaller, and higher density mounting of each mechanical component is required. ing.

Further, when the size of each mechanical component, especially the actuator is reduced by making the magnetic disk device lighter, thinner, shorter and smaller, the recording / reproducing signal line connected to the recording / reproducing magnetic head and the servo magnetic head are connected. The servo signal lines thus formed are also arranged close to each other.

Since an alternating current having a relatively high level flows through the recording / reproducing signal line, when the recording / reproducing signal line and the servo signal line are arranged close to each other, an alternating current flowing through the recording / reproducing signal line is generated. The generated electromagnetic waves may adversely affect the servo signal line as electromagnetic noise.

Therefore, there is a demand for an actuator structure in which the recording / reproducing signal line does not adversely affect the servo signal line even if the magnetic disk device is made lighter, thinner, shorter and smaller.

[0006]

2. Description of the Related Art Conventionally, so-called servo surface servo magnetic recording is performed by taking in servo information written on a dedicated servo surface and positioning a magnetic head (read / write head) for recording / reproducing processing on a target track. In a disk device, a read / write head and a servo magnetic head are arranged on an arm. The actuator includes a servo semiconductor device (servo IC) connected to the servo magnetic head, and a read / write semiconductor device (read / write I) connected to the read / write head.
C) and are attached.

By the way, a considerable current flows through the recording / reproducing IC at the time of reading / writing data (especially at the time of writing). Therefore, when the servo IC and the read / write IC are arranged close to each other, there is a problem that noise is added to the servo IC when the read / write IC is written.

Further, a recording / reproducing signal line (read / write) connecting the read / write IC and the read / write head is connected.
The same is true even if the write signal line) and the servo signal line connecting the servo IC and the servo magnetic head are arranged close to each other, and induction noise due to electromagnetic induction is generated from the read / write signal line. The induced noise (hereinafter referred to as the servo noise) affects the servo signal line, and the servo noise is superimposed on the servo signal.

As described above, when the read / write IC or the read / write signal line adversely affects the servo IC or the servo signal line, the servo signal is disturbed and the positioning accuracy of the actuator is deteriorated. There was a point.

Conventionally, the following actuator structure has been proposed as a means for solving the above problems.

The read / write signal line and the servo signal line are arranged in a non-parallel position and separated from each other as much as possible.

The opposing read / write head and servo magnetic head are fixed to the actuator by being displaced in the arm rotation direction or in the circumferential direction of the magnetic disk.

The servo magnetic head and the read / write head are not mounted on the same arm.

Servo IC and read / write IC
Are arranged on different surfaces of the actuator (specifically, the outer peripheral portion of the rotating shaft).

[0015]

However, the actuator structure described above has a problem that the size of the arm becomes large, and the actuator becomes large accordingly, which is against the miniaturization of the magnetic disk drive.

In the above actuator structure,
The servo arm must be provided separately from the recording / reproducing arm, so that the weight of the entire arm becomes large and the power consumption of the voice coil motor, which is the drive source of the actuator, increases. In addition, the actuator is upsized by the provision of the servo arm.

Further, in the above actuator structure,
Each IC is arranged so as to project to the outer peripheral portion of the rotating shaft.
The outer peripheral position of the rotary shaft of the actuator is a portion where other mechanical parts are densely arranged, and each IC is configured to rotate as the arm rotates. Therefore, even if the arm rotates around the outer periphery of the rotation axis of the actuator, each IC
It is necessary to provide a space so as not to contact the other mechanical device. Therefore, there is a problem that the magnetic disk device becomes large in size even in the above actuator structure.

On the other hand, in the actuator structure which focuses on the miniaturization of the magnetic disk device, the read / write side component and the servo side component are close to each other,
As described above, the servo noise is superimposed on the servo signal and the positioning accuracy of the actuator is deteriorated.

The present invention has been made in view of the above points, and an object thereof is to provide an actuator structure of a magnetic disk device capable of improving the positioning accuracy of the actuator while making the magnetic disk device lighter, thinner and smaller. To do.

[0020]

The above-mentioned problems can be solved by the following means.

According to the first aspect of the present invention, there is provided a plurality of arms equipped with a recording / reproducing magnetic head for performing magnetic recording / reproducing processing on the magnetic disk, and the plurality of arms are rotated in the radial direction of the magnetic disk. In order to position the recording / reproducing magnetic head at a predetermined position on the magnetic disk by operating it, and to perform positioning control of the recording / reproducing magnetic head together with the recording / reproducing magnetic head in at least one of the plurality of arms. A flexible circuit board having a servo magnetic head mounted thereon and having a first substrate portion connected to the recording / reproducing magnetic head and a second substrate portion connected to the servo magnetic head. An actuator structure of a magnetic disk device comprising: a virtual line connecting the center of rotation of the arm and the center of the head of each magnetic head. In addition, the flexible circuit board is configured such that the first board portion and the second board portion can be independently pulled out, and one of the arms separated by the virtual line is provided with a flexible circuit board 1 board part is provided, and the second part of the flexible circuit board is attached to the other part of the arm separated by the virtual line.
It is characterized in that the board portion of (1) is pulled out and arranged.

According to a second aspect of the present invention, there is provided a plurality of arms having a recording / reproducing magnetic head for performing magnetic recording / reproducing processing on the magnetic disk, and the plurality of arms are rotated in a radial direction of the magnetic disk. It is operated to position the recording / reproducing magnetic head at a predetermined position on the magnetic disk, and
At least one of the plurality of arms is equipped with a recording / reproducing magnetic head together with a servo magnetic head for controlling the positioning of the recording / reproducing magnetic head, and In the actuator structure of a magnetic disk device including a flexible circuit board on which a connected recording / reproducing semiconductor device and a servo semiconductor device connected to the servo magnetic head are arranged, a rotation center of the arm is provided. Assuming a virtual line connecting the head center of each magnetic head, a recording / reproducing signal line for connecting the recording / reproducing magnetic head and the flexible circuit board to one side of the arm separated by this virtual line, and recording / reproducing. Of the servo semiconductor device, and at the other side of the arm separated by the virtual line, the servo magnetic Servo signal line connecting the head and the flexible circuit board, and is characterized in that it has provided the servo semiconductor device.

According to a third aspect of the present invention, in the actuator structure of the magnetic disk device according to the first aspect, the flexible circuit board is provided with the recording / reproducing semiconductor device and the recording / reproducing signal line is provided. A first substrate portion on which a recording / reproducing terminal portion to be connected is formed, and the servo semiconductor device is disposed, and a servo terminal to which the servo signal line is connected is formed on a second substrate portion. And a substrate part of the unit are integrally formed, and
The first board portion is arranged at one portion of the arm separated by the virtual line, and the second substrate portion is drawn out to the other portion of the arm separated by the virtual line. It is a feature.

Further, in the invention of claim 4, in the actuator structure of the magnetic disk device according to claim 1, a magnetic field is provided between a portion where the recording / reproducing magnetic head is arranged and a portion where the servo magnetic head is arranged. It is characterized in that a body metal member is interposed.

[0025]

According to the first aspect of the invention, the first board portion of the flexible circuit board is provided at one portion of the arm separated by a virtual line connecting the center of rotation of the arm and the head center of each of the magnetic heads. Since the second substrate portion is disposed in the other portion, the recording / reproducing signal line and the servo signal line are disposed so as to be largely separated from each other about the virtual line.

Therefore, the recording / reproducing semiconductor device and the recording / reproducing signal line do not adversely affect the servo semiconductor device and the servo signal line, and the positioning accuracy of the actuator can be improved.

According to the second aspect of the present invention, the recording / reproducing signal line and the recording / reproducing semiconductor are provided at one portion of the arm separated by a virtual line connecting the center of rotation of the arm and the head center of each magnetic head. Since the device is arranged and the servo signal line and the servo semiconductor device are arranged in the other part,
The arrangement positions of the recording / reproducing signal line and the servo signal line and the arranging positions of the recording / reproducing semiconductor device and the servo semiconductor device are arranged largely apart from each other with the virtual line as a center.

Therefore, the recording / reproducing semiconductor device and the recording / reproducing signal line do not adversely affect the servo semiconductor device and the servo signal line, and the positioning accuracy of the actuator can be improved. In addition, since the recording / reproducing semiconductor device and the servo semiconductor device are arranged on the arm with the virtual line substantially at the center, each semiconductor device does not interfere with other mechanical devices, and the magnetic disk device is compact. Can be realized.

Further, according to the invention of claim 3, the first substrate portion is arranged at one part of the arm separated by the virtual line, and the second substrate portion is separated by the virtual line. Since it can be pulled out to the other part of the arm, a recording / reproducing magnetic head, a recording / reproducing signal line, a recording / reproducing semiconductor device, a servo magnetic head, a servo signal line, and a servo semiconductor device can be obtained with one flexible circuit board. Can be wired. Further, since the second substrate portion is pulled out to the other portion of the arm separated by the virtual line, the servo semiconductor device can be arranged close to the servo magnetic head.

On the recording / reproducing side, the effect of servo noise is most prominent in the portion from each magnetic head to each semiconductor device. Therefore, by extending the second substrate portion and disposing the servo semiconductor device in the vicinity of the servo magnetic head, it is possible to reduce the portion affected by servo noise and improve the positioning accuracy of the actuator. You can

Further, in the invention of claim 4, a magnetic metal member functioning as a shield material is interposed between the disposing portion of the recording / reproducing magnetic head and the disposing portion of the servo magnetic head. It is possible to reduce the influence of servo noise at the magnetic head mounting position.

[0032]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 8 is an internal plan view of a magnetic disk device to which an actuator structure according to an embodiment of the present invention is applied.

In the figure, a magnetic disk (hereinafter simply referred to as "disk") 1 serving as a recording medium is fixed on a spindle motor 2 which is rotated at a high speed, and a plurality of disks 1 are stacked on a base 7. Are arranged in a fixed state. An actuator 3, which is an essential part of the present invention, is arranged on the side of the arrangement position of the disk 1. The actuator 3 includes a head arm 4, a voice coil motor (V
CM) 5, rotating shaft 6, spring arm 10, flexible circuit board (hereinafter referred to as FPC) 13, and the like.

Magnetic head for recording / reproducing data on / from the disk 1 (hereinafter referred to as read / write head)
8 is fixed to the tip of the head arm 4. Further, the magnetic disk apparatus according to the present embodiment takes in servo information written on a dedicated servo surface of the disk 1 and positions the read / write head 8 on a target track. Since it is a disk device, a magnetic head (hereinafter referred to as a servo head) 9 for reading the servo information written on the servo surface is fixed to the tip of the head arm 4. A plurality of read / write heads 8 are provided corresponding to the plurality of disks 1 provided, but only one servo head 9 is provided, and the placement position thereof is the actuator 3 It is selected in the approximate center position.

A VCM coil is fixed to the base end side of the head arm 4, and a central portion of the VCM coil is rotatably held by a rotary shaft 6 embedded in a base 7.
The VCM 5 is composed of a VCM magnet, an upper yoke, a lower yoke, etc., and the head arm 4 is configured to rotate in the direction shown by the arrow in the figure when the VCM magnet is energized. Therefore, when the VCM 5 is driven, each of the magnetic heads 8 and 9 arranged at the tip of the head arm 4 is configured to face a predetermined track on the disk 1.

Next, the structure of the actuator 3, which is a main part of the present invention, will be described with reference to FIGS. 1 to 7 in addition to FIG. 1 is a plan view of the actuator 3 (showing a state in which both the read / write head 8 and the servo head 9 are provided), and FIG. 2 is a plan view of the actuator 3 in which only the servo head 9 is provided. FIGS. 3 and 6 are enlarged views of the spring arm 10 that constitutes the actuator 3, and FIG.
5 is a left side view of the actuator 3, FIG. 5 is a right side view of the actuator 3 (a spring arm on which the read / write head 8 is disposed is not shown), and FIG. 7 is an enlarged view of the vicinity of the head. Is.

As described above, the actuator 3 is composed of the head arm 4, the VCM 5, the rotating shaft 6, the spring arm 10, the FPC 13, and the like. The head arm 4 integrally includes a bearing portion 11 that is supported by the rotating shaft 6 and a plurality of arm portions 12 that are formed to extend laterally (direction toward the disc 1) from the bearing portion 11. It is configured. Further, the read / write head 8 and the servo head 9 are arranged via the spring arm 10 in the arm portion 12a located substantially at the center of the plurality of arm portions 12 (see FIGS. 4 to 6). detailed).

A read / write signal line 14 is connected to the read / write head 8, and a servo signal line 15 is connected to the servo head 9. The other end of the read / write signal line 14 is soldered to a read / write connection pad (hereinafter, referred to as R / W pad) 16 formed on the FPC 13, and the other end of the servo signal line 15 is also connected. Are soldered to the servo pads 17 formed on the FPC 13.

9 and 10 are enlarged views of the FPC 13. As shown in FIG. 9, the FPC 13 is a single flexible circuit board having a rectangular shape, and has a recording / reproducing semiconductor device (hereinafter referred to as a read / write IC).
18, 19 and a servo semiconductor device (hereinafter referred to as servo I
20 is provided. This F
A cutting portion 21 is formed in a U shape in a substantially central portion of the PC 13, and the FPC 13 is divided into a first substrate portion 22 and a second substrate portion 23 by the cutting portion 21. The first substrate portion 22 has the above-mentioned read / write IC 18,
19 and the R / W pad 16 are arranged, and the servo IC 20 and the servo pad 17 are provided on the second substrate portion 23.
Is provided. Particularly, in the second substrate portion 23, the arrangement position of the servo IC 20 and the servo pad 17 is selected in the vicinity of the end portion of the second substrate portion 23.

In the FPC 13 configured as above, the cutting section 2
Since 1 is formed, the second substrate portion 23 can be displaced with respect to the first substrate portion 22 as shown in FIG. Therefore, the second substrate portion 22
It is possible to dispose the substrate portion 23 in the state of being pulled out.

Here, attention will be paid to the arrangement of the respective constituent parts of the actuator 3 described above, and the following description will be given. In the present invention, a virtual line 25 connecting the center position of the rotating shaft, which is the center of rotation of the head arm 4, and the head center of the magnetic heads 8 and 9 when viewed in plan (see FIGS. 1 and 8).
(Indicated by a one-dot chain line in FIG. 2) is assumed, and the read / write component and the servo component are defined around the virtual line 25 and are spaced apart from each other.

Specifically, the configuration shown in FIG. 1 will be described as an example. The read / write signal line 14, the R / W pad 16, and the first substrate portion 22 which are components for read / write. The read / write ICs 18 and 19 are collectively arranged on the right side of the virtual line 25 of the head arm 12 (including the spring arm 10). Further, the servo signal line 15, the servo pad 17, the second board portion 23, and the servo IC 2 which are the components for the servo.
0s are collectively arranged on the left side of the virtual line 25 of the head arm 12 (including the spring arm 10).

In the above arrangement structure, the second substrate portion 23 is formed so that the second substrate portion 23 can be pulled out from the first substrate portion 22 because the cutting portion 21 is formed as described above. The second substrate portion 23 extends from the left side to the right side of the virtual line 25 along the outer periphery of the support shaft portion 11. Therefore, by configuring the FPC 13 as described above, it becomes possible to dispose each component separately on the read / write side and the servo side around the virtual line 25 by one FPC 13.

As described above, the read / write components 14, 16, 22, 18, and 19 are arranged at the left side portion of the head arm 12 separated by the virtual line 25, and at the right side portion. Servo components 15, 17,
By disposing 23 and 20, the disposition position of the read / write signal line 14 and the disposition position of the servo signal line 15 are separated with the virtual line 25 being substantially the center. Similarly, the arrangement positions of the read / write ICs 18 and 19 and the arrangement position of the servo IC 20 are also separated from each other with the virtual line 25 being substantially the center.

Therefore, the read / write signal line 14 and the read / write ICs 18 and 19 are connected to the servo signal line 1 by the servo signal line 1.
5 and the servo IC 20 are not adversely affected, and the positioning accuracy of the actuator 3 can be improved. Further, the read / write ICs 18 and 19 and the servo IC 20 are separately arranged with the virtual line substantially at the center. Therefore, the ICs 18 to 20 can be arranged at positions where they do not interfere with other mechanical devices, and the magnetic disk device can be downsized.

Further, by constructing the structure of the FPC 13 by the first board portion 22 and the second board portion 23 as described above, the second board portion 23 is made into the virtual line 25 as described above.
Since it is possible to pull out to the servo side of the head arm 4 separated by, the servo IC 20 can be disposed close to the servo head 9.

On the read / write side, the most noticeable effect of servo noise is from the magnetic heads 8 and 9 to the ICs 18 to 20. Therefore, by pulling out the second substrate portion 23 and arranging the servo IC 20 close to the servo head 9, it is possible to reduce the portion where the influence of servo noise occurs, which also results in the positioning accuracy of the actuator 3. Can be improved.

On the other hand, as shown in FIG. 3, the tip of the spring arm 10 is generally sharp (narrow), and the read / write head 8 and the servo head 9 are arranged at the tip. Since it is provided, the read / write head 8 and the servo head 9, and the read / write signal line 14 and the servo signal line 15 are arranged at the closest position in this portion, which causes the servo noise. It is easily affected.

Therefore, in this embodiment, as shown in FIGS. 1, 3 and 7, a magnetic material is provided at the tip of the spring arm 10 between the read / write head 8 and the servo head 9. A metal plate 26 is provided. The magnetic metal plate 26 is, for example, an iron plate having a predetermined thickness and functions as a shield material. Therefore, due to the structure of the actuator 3, it is inevitable to reduce the influence of servo noise at the tip end portion of the spring arm in which the read / write side component and the servo side component are arranged close to each other.
The positioning accuracy of the actuator 3 can be improved.

FIG. 11 shows various shapes of the magnetic metal plate 26. The magnetic metal plate 26a shown in FIG. 3A has a square shape, and the magnetic metal plate 26b shown in FIG. 3B has a shape obtained by abutting two trapezoidal shapes. The same figure (C)
The magnetic metal plate 26c shown in FIG. 6 has a trapezoidal shape, and the magnetic metal plate 26d shown in FIG.
Has a rectangular shape. in this way,
The magnetic metal plate 26 may have any shape as long as it can electromagnetically shield the read / write side component and the servo side component.

[0051]

As described above, according to the present invention, the recording / reproducing magnetic head and the flexible circuit are provided at one portion of the arm separated by a virtual line connecting the center of rotation of the arm and the center of the head of each magnetic head. A recording / reproducing signal line for connecting to a substrate and a semiconductor device for recording / reproducing are arranged, and a servo signal line for connecting a magnetic head for servo and a flexible circuit board and a semiconductor device for servo are arranged at the other part. As a result, the arrangement positions of the recording / reproducing signal line and the servo signal line and the arranging positions of the recording / reproducing semiconductor device and the servo semiconductor device are arranged largely apart from each other with the virtual line as the center. Therefore, the recording / reproducing semiconductor device,
The recording / reproducing signal line does not adversely affect the servo semiconductor device and the servo signal line, and the positioning accuracy of the actuator can be improved. In addition, since the recording / reproducing semiconductor device and the servo semiconductor device are arranged on the arm with the virtual line substantially at the center, each semiconductor device does not interfere with other mechanical devices, and the magnetic disk device is compact. Can be realized.

Further, the first substrate portion can be arranged at one portion of the arm separated by the virtual line, and the second substrate portion can be pulled out to the other portion of the arm separated by the virtual line. Therefore, the wiring of the recording / reproducing magnetic head, the recording / reproducing signal line, the recording / reproducing semiconductor device, the servo magnetic head, the servo signal line, and the servo semiconductor device can be performed with one flexible circuit board. Further, since the second substrate portion is pulled out to the other portion of the arm separated by the virtual line, the servo semiconductor device can be arranged close to the servo magnetic head. On the recording / reproducing side, the effect of servo noise is most prominent in the portion from each magnetic head to each semiconductor device. Therefore, by extending the second substrate portion and disposing the servo semiconductor device in the vicinity of the servo magnetic head, it is possible to reduce the portion affected by servo noise and improve the positioning accuracy of the actuator. You can

Further, since a magnetic metal member functioning as a shield material is interposed between the portion where the recording / reproducing magnetic head is arranged and the portion where the servo magnetic head is arranged, the servo at the magnetic head mounting position is improved. The influence of noise can be reduced.

[Brief description of drawings]

FIG. 1 is a diagram for explaining an actuator structure according to an embodiment of the present invention.

FIG. 2 is a diagram for explaining an actuator structure that is an embodiment of the present invention.

FIG. 3 is an enlarged view of a spring arm.

FIG. 4 is a left side view of the actuator.

FIG. 5 is a right side view of the actuator.

FIG. 6 is a side view of a spring arm.

FIG. 7 is an enlarged view showing the vicinity of a head.

FIG. 8 is an internal plan view of a magnetic disk device to which an actuator structure according to an embodiment of the present invention is applied.

FIG. 9 is a diagram showing an FPC.

FIG. 10 is a diagram showing a state in which the second substrate portion is pulled out from the first substrate portion.

FIG. 11 is a diagram showing the structure of various magnetic metal plates.

[Explanation of symbols]

 1 Disk 3 Actuator 4 Head Arm 5 VCM 6 Rotating Axis 7 Base 8 Read / Write Head 9 Servo Head 10 Spring Arms 12a, 12b Arm Part 13 FPC 14 Read / Write Signal Line 15 Servo Signal Line 16 R / W pad 17 Servo pad 18,19 Read / write IC 20 Servo IC 21 Cutting portion 22 First substrate portion 23 Second substrate portion 25 Virtual line 26, 26a to 26d Magnetic metal plate

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomio Sukagawa 5400, Omori, Higashine, Higashine, Higashine, Yamane Prefecture 2 Inside Yamagata Fujitsu Limited

Claims (4)

[Claims] 1. A plurality of arms (4) having a recording / reproducing magnetic head (8) for performing a magnetic recording / reproducing process on a magnetic disk (1), the plurality of arms (4) being provided. The magnetic disk (1) is rotated in the radial direction to position the recording / reproducing magnetic head (8) at a predetermined position on the magnetic disk (1), and at least one of the plurality of arms (4) is The arm (4) is equipped with the recording / reproducing magnetic head (8) together with a servo magnetic head (9) for performing positioning control of the recording / reproducing magnetic head (8), and First connected to magnetic head for recording / reproduction (8)
An actuator structure for a magnetic disk device, comprising: a flexible circuit board (13) having a substrate part (22) of (1) and a second substrate part (23) connected to the servo magnetic head (9), The rotation center of the arm (4) and the magnetic heads (8,
Assuming a virtual line (25) connecting the center of the head of (9), the flexible circuit board (13) is connected to the first board section (2).
2) and the second substrate portion (23) can be independently pulled out, and the arm (4) separated by the virtual line (25)
The first part of the flexible circuit board (13)
The arm (4) on which the substrate part (22) of the above is disposed and separated by the virtual line (25)
The second part of the flexible circuit board (13) on the other part of
2. An actuator structure of a magnetic disk device, wherein the substrate portion (23) of FIG. 2. A plurality of arms (4) carrying a recording / reproducing magnetic head (8) for performing a magnetic recording / reproducing process on a magnetic disk (1), the plurality of arms (4) being provided. The magnetic disk (1) is rotated in the radial direction to position the recording / reproducing magnetic head (8) at a predetermined position on the magnetic disk (1), and at least one of the plurality of arms (4) is The arm (4) is equipped with the recording / reproducing magnetic head (8) together with a servo magnetic head (9) for performing positioning control of the recording / reproducing magnetic head (8), and A flexible structure in which a recording / reproducing semiconductor device (18, 19) connected to the recording / reproducing magnetic head (8) and a servo semiconductor device (20) connected to the servo magnetic head (9) are arranged. Equipped with a circuit board (13) That the actuator structure of a magnetic disk apparatus, the arm (4) of the rotation center and the magnetic heads (8,
Assuming a virtual line (25) connecting the head center of 9), the arm (4) separated by the virtual line (25)
A recording / reproducing signal line (14) for connecting the recording / reproducing magnetic head (8) and the flexible circuit board (13) to one part, and the recording / reproducing semiconductor device (18, 19).
And the arm (4) separated by the virtual line (25)
The servo signal line (15) for connecting the servo magnetic head (9) and the flexible circuit board (13), and the servo semiconductor device (20) are arranged in the other part of the above. Actuator structure of magnetic disk device. 3. The actuator structure of the magnetic disk device according to claim 1, wherein the flexible circuit board (13) is provided with the recording / reproducing semiconductor device (18, 19), and the recording / reproducing signal line. A first substrate portion (22) on which a recording / reproducing terminal portion (16) to which (14) is connected is formed.
And a second substrate portion (23) on which the servo semiconductor device (20) is arranged and a servo terminal (17) to which the servo signal line (15) is connected is formed. It is configured to be integrally formed, and the first substrate portion (22) is connected to the virtual line (2).
5) is arranged in one part of the arm (4) separated, and the second substrate part (23) is pulled out to the other part of the arm (4) separated by the virtual line (25). An actuator structure for a magnetic disk drive having the above-mentioned configuration. 4. The actuator structure of the magnetic disk device according to claim 1, wherein the magnetic head for recording / reproducing (8) and the servo magnetic head (9) are arranged between the arranging portion. An actuator structure for a magnetic disk device, wherein a magnetic metal member (26) is interposed.