JPH07334945A - Disk device - Google Patents

Abstract

PURPOSE:To optimize the structure and mechanism for reduction of the size, weight and thickness of the constituting elements of a disk device. CONSTITUTION:An arm part 80, a shaft mounting part 85 and a coil supporting part 88 are arranged so that the centroid 100 on the coil side exists on a straight line 102 connecting a rotating center 86 and the centroid 98 on the head side for the purpose of balance adjustment according to the reduction in the size and weight of an actuator 26. In addition to the above, an improvement in the assembling characteristic of a VCM, torque increase, fixing of an FPC connection band with one operation, noise prevention of lead patterns and insulation of a base and cover according to biasing of an MR read head are attained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk device which is designed to have a small size and a thin shape at the same time as the storage capacity is expanded.
The present invention relates to a small disk device using an inch disk medium.

[0002]

2. Description of the Related Art In recent years, small hard disks have been mounted as external storage devices for notebook computers and portable communication terminals. As such a small hard disk, for example, a 2.5 inch small disk medium is used.
The one with 3 built-in is used.

In such a small-sized disk device, there is a demand for further reduction in the size, weight and thickness of the device at the same time as the storage capacity is expanded. The reduction in size, weight and thickness of the disk device saves the installation space when the disk device is installed in a notebook computer or the like. In addition, the entire computer including the magnetic disk device becomes smaller, making it easier to carry.

Furthermore, the drive load of the spindle motor and voice coil motor is reduced, and power consumption can be reduced. Notebook computers and mobile communication terminals can operate on battery power, so performance depends on how long they can be used without battery charging. Therefore, if the power consumption of the disk device is reduced, the battery usage time is extended accordingly and the performance is improved.

[0005]

However, there are various problems as described below in order to further reduce the size, weight and thickness of the disk device. First, an in-line type actuator for positioning the head is provided with an arm portion for supporting the head on one of the rotary shafts and a movable coil of a voice coil motor on the other of the rotary shafts. At the same time, the actuator must be lightweight and balanced on the head side and the coil side. In particular, in recent years, the tip of the arm has an asymmetric arm shape bent toward the center of the disk so that the head direction does not fall largely from the track tangent line even if the rotational position of the actuator changes.

Therefore, in addition to the balance adjustment in the front-rear direction, the balance in the left-right direction due to the asymmetric arm shape must be simultaneously obtained. Conventionally, such balance adjustment is performed by weight adjustment such as changing the wall thickness of the moving coil on the left and right sides. However, the design work of simultaneously adjusting the front-rear and left-right balance of the actuator by adjusting the wall thickness is complicated, and there is a problem that the shape balance is greatly disturbed even if the weight balance is achieved.

Accordingly, it is an object of the present invention to provide a disk drive having a balanced actuator with a relatively simple shape. In a voice coil motor that drives an actuator, a yoke including a permanent magnet is fixedly arranged on a housing base with respect to a movable coil on the actuator side. Conventionally, the yoke-side assembly including the permanent magnet has been assembled and fixed with a screw, an adhesive, caulking or the like. Therefore, the number of parts and the number of assembling steps are increased, and the assembling work is complicated.

Therefore, another object of the present invention is to provide a disk device which can be easily assembled on the yoke side of a voice coil motor with a small number of parts. Further, in the conventional voice coil motor, the magnet on the yoke side is set to the same size as the left and right coil portions of the rectangular movable coil on the actuator side so that the magnetic flux passes through the coil effective portion that generates the rotational torque. I have to. However, at the end of the magnet, the magnetic flux density of the coil is reduced due to the leakage magnetic flux, and the effective coil length is not fully utilized.

Therefore, another object of the present invention is to provide a disk device which maximizes the effective length of the coil to increase the torque generated by the magnetic circuit. In a disk device, generally, a movable side actuator and a fixed side circuit board are connected by a connection band of a flexible printed circuit (hereinafter referred to as “FPC”). In this case, the assembling work for positioning and fixing the FPC connection band on the fixed side becomes important. If there is a slight mistake in this assembly work, the FPC
The bending state of the connection band is likely to vary, the force applied to the actuator changes abnormally, or the FPC is
There is a problem that the connecting band is flapping and comes into contact with parts such as ICs and resistors.

Therefore, another object of the present invention is to provide a disk device in which the FPC connection band can be easily assembled with high positioning accuracy and the contact with other parts due to flapping and the force applied to the actuator are stabilized. . Further, in order to reduce the track pitch of the disk medium and improve the recording density, an MR head using a magnetoresistive element is used as a read head. In the read operation of the MR head, a specified DC bias current is supplied to the MR head in order to secure a weak S / N ratio of the read signal. But,
When a bias current is applied to the MR head, the head core has a potential.

Therefore, when the head core and the disk medium come into contact with each other, a current flows between the core and the disk medium, and there is a risk of destroying the head core. Therefore, it is necessary to give the disk medium the same potential as the head core. Conventionally, a signal voltage is independently wired from the fixedly installed circuit section to the actuator side to supply a bias voltage to the disk medium. For this reason, the provision of the dedicated bias supply line complicates the arrangement of parts, requires a lot of man-hours, and has a problem that an external force is applied to the actuator by the dedicated bias line.

Therefore, another object of the present invention is to provide a disk device which can easily supply a bias to a disk medium via an actuator. Furthermore, when an MR head is used as the read head, when a read signal passes through the circuit pattern formed in the FPC connection band, external noise is introduced as induction noise on the circuit pattern, and the S / N ratio deteriorates. there were.

Therefore, another object of the present invention is to provide a disk device in which the interference of external noise on the FPC lead pattern is prevented by the arrangement of the FPC circuit pattern. Further, as a bias is supplied to the MR head during a read operation, the disk enclosure itself having the disk mechanism built therein will have a certain potential. For this reason, for example, when a disk device is built in a notebook computer as an external storage device, a new problem arises in that the built-in device must be insulated.

Therefore, another object of the present invention is to provide a disk device which does not cause a short circuit due to the potential due to the bias supply even when the disk device is assembled to the system side unit. Further, it is a main object of the present application to provide a disk device that eliminates waste of space and high-speed operation due to arrangement of each component, achieves miniaturization, and can maintain high quality even when miniaturized.

[0015]

In order to achieve these objects, the present invention is constructed as follows. Corresponding reference numerals in the examples are also shown in parentheses. First, the present invention relates to a disk medium (3) rotated by a spindle dollar motor (22).
0), an actuator (26) that movably supports the head (14) in the radial direction with respect to the recording surface of the disk medium (30), and a voice that rotates an actuator (26) within a predetermined rotation angle range. Coil motor (VCM; 2
0) and a disk device provided with.

The disk device of the present invention obtains a balanced actuator with a relatively simple shape. The actuator (26) includes an arm portion (80) for mounting the head (14) at its tip, a shaft mounting portion (85) integrally formed at the base of the arm portion (80), and a shaft mounting portion (85). The voice coil motor (20) is integrally formed in the rear part and is constituted by a coil support part (88) supporting the movable coil (90).

Therefore, the arm portion (100) is arranged such that the center of gravity (100) on the coil side is aligned with the straight line (102) connecting the center of rotation (92) of the actuator (26) and the center of gravity (98) on the head side. 80), the shaft mounting portion (85) and the coil support portion (88) are arranged. Here, the arm portion (80) of the actuator (26) has an asymmetrical shape that is bent toward the disk center side at the tip end side on which the head (14) is mounted.

Further, the disk device of the present invention utilizes the attractive force of the magnet in order to easily assemble the yoke side of the voice coil motor with a small number of parts.
First, the voice coil motor (20) includes a flat movable coil (90) supported on the actuator (80) side,
A pair of permanent magnets (154, 156) fixedly arranged at positions sandwiching the movable coil (90), and the permanent magnets (154, 154).
156) and is composed of a pair of yoke members (24, 152) forming a magnetic circuit. Therefore, the pair of yoke members (24, 152) are connected to the permanent magnets (154, 156).
The combined structure is formed by adsorbing and fixing the movable coil (90) to form a storage space.

Specifically, the pair of yoke members (24, 1)
52) are flat plate members. On one plate member, standing pieces (174, 176, 1) that determine the coil accommodation interval between the pair of permanent magnets (154, 156) are provided.
78) and at least one standing piece (1
Protrusions (166) for positioning are provided at the tip of 76).
Further, a positioning receiving hole (168) is formed at a position of the other plate member facing the protrusion (166).

Further, in the disk device of the present invention, in order to maximize the effective length of the coil and increase the torque generated by the magnetic circuit, the inner ends of the front and rear coil portions in the arm radial direction of the movable coil (90). For each of (180, 182), the front and rear outer ends (178, 184, 186, 188) of the pair of permanent magnets (154, 156) are slightly overlapped to generate left and right torque of the movable coil (90). The magnetic flux of the permanent magnets (154, 156) is passed over the effective portion.

The disk device of the present invention adopts a one-touch fixing structure in order to easily and fixedly attach the FPC connection band with high positioning accuracy and to stabilize contact with other parts due to flapping and force applied to the actuator. . This one-touch fixing structure is erected from the circuit board (60), and a band withdrawing portion (26) integrally withdrawing the connection band (62) from one of the upright side ends through a J-shaped bent portion.
5) and the circuit board (60), and the J-shaped receiving portion (24) for fixing the band drawing portion (265) to the side surface.
The plate supporting member (240) provided with the band supporting portion (244) provided with 8) is provided on the fixed side, and the band pressing member (260) is mounted and held.

The band pressing member (260) has a leaf spring shape in which two pieces are folded, and an inverted J-shaped pressing portion (272) formed at the tip of one leaf spring portion (262) is connected to the band supporting portion (262). 248) J-shaped receiving portion (248) is pushed in with one touch to fix and hold the band root. Further, the band pressing member (260) is provided with a protrusion (274) which is fitted into the fitting hole (246) formed in the band supporting part (244) at the tip of the other leaf spring part (264) folded in two. Will be prevented from falling out. Band holding member (260)
Is a positioning piece (2) for the band supporting portion (244) at the side end of the leaf spring portion (262) for band holding folded in two.
66, 268, 270) and connecting band (62)
To position.

The disk device of the present invention prevents the external noise from interfering with the FPC lead pattern by disposing the FPC circuit pattern. Therefore, of the pair of connection patterns for the read head (15) and the write head (16) of the plurality of head portions (14) formed in the FPC connection band (62), the connection pattern for the write head (16) is Place it so that it is located on the outermost side.

During the read operation, the write head (1
The outermost connection pattern for 6) is electrically opened or electrically connected to the ground.
Further, in the disk device of the present invention, even when the disk device is assembled to a system-side unit such as a notebook computer, in order to prevent a short circuit due to the potential due to bias supply to the read head using the MR head, Provide an insulating structure on the mounting surface to other units.

As this insulating structure, an insulating layer is formed by forming a rubber lining or an insulating film. In addition, an insulating mounting block member is provided on the housing side, and the mounting block member has a unit mounting surface slightly protruding from the housing surface in order to provide a step between the mounting block member and the unit side. As the mounting block member, a metal block having mounting screw holes, which is rubber-lined, or a resin block having mounting screw holes can be used. Also cover (1
The outer shape of (0) may be formed so as not to protrude from the outer shape of the base (12).

Further, according to the present invention, since the bias supply is easily supplied to the disk medium through the actuator, the head portion (14) mounted on the actuator (26) and the fixedly arranged circuit board (60) are connected to each other. FPC to connect
In the connection band (62), a bias supply pattern (308) for applying a bias voltage to the actuator (26) is formed in addition to the pair of connection patterns for the read head (15) and the write head (16).

[0027]

In the disk device of the present invention as described above, the following effects can be obtained. With the center of rotation of the actuator as the boundary,
By comparing the center of gravity calculated on the head side with the center of rotation so that the center of gravity on the coil side is on a straight line, the coil side is rotated to determine the position. With a simple shape, a good balance can be obtained in both left and right and front and back directions, and the structure is highly stable against external vibration and shock.

Further, since the yoke is assembled and fixed by utilizing the attractive force of the magnet, screws, adhesives, caulking, etc. are not required for the yoke assembly, and the number of parts and the number of assembling steps can be reduced and the assembling work can be simplified. It will be possible. Further, the magnetic flux density at the end portion of the magnet is reduced due to the generation of leakage magnetic flux that does not pass through the coil, but the end portion of the magnet is expanded to the front and rear of the coil beyond the torque generation effective portion on the left and right of the coil. As a result, even in the magnet end portion, a uniform magnetic flux is passed through the torque generating effective portions on the left and right sides of the coil to maximize the effective coil length. Therefore, the effective length of the coil can be substantially lengthened, and the rotational torque generated by the magnetic circuit can be increased.

With the expansion of the magnet in the front-back direction,
Due to the magnetic flux passing through the front and rear parts of the coil, the thrust force of the actuator increases at the same time as the rotational torque increases.
Therefore, the width of overlap between the front and rear portions of the coil of the magnet is determined so as to increase the rotational torque within the range where the thrust force does not exceed the specified value. Furthermore, the FPC connection band is fixedly supported by attaching the band pressing member having a spring property to the FPC connection band with a single touch, preventing the fixing portion from fluttering and eliminating the risk of contacting other parts. Further, the variation of the external force applied to the actuator due to the bending of the FPC connection band is prevented, and the movement is stabilized.

By providing a pattern for supplying a bias voltage in the FPC connection band, connection can be easily made only by screwing the bias supply pattern on the actuator side. Further, when an MR head is used as the read head, the number of lead wires per head is 4, and the FPC connection band is provided with a dedicated read pattern and write pattern. The read signal of the MR head is considerably smaller than that of the conventional magnetic head, and it is desired to arrange the ground pattern on the outermost side of the FPC connection band to prevent noise during reading, but the pattern mounting width becomes large. Therefore, paying attention to the fact that the write pattern is resting at the time of reading, the write pattern is arranged so as to come to the outermost side in order to function as a dummy pattern for noise prevention.

At the time of reading, at least three stray capacitances are formed between the two outer write patterns and the first read pattern, and external noise is divided by the stray capacitance before noise induction to the read pattern. It is pressed and can be reduced to 1/3. Further, by installing and connecting the outer write pattern to the ground during reading, it is possible to substantially completely prevent the external noise from being induced to the read pattern. As a result, S of a weak read signal from the MR head
The / N ratio can be guaranteed. As a result, it is possible to reliably prevent noise in the read signal of the lead pattern without increasing the width of the pattern.

In a disk device using an MR head as a read head, a bias voltage is also supplied to the disk medium via an actuator at the time of reading, so that the base and the cover also have a potential. Therefore, there is a risk that a potential difference will occur between the disk device and the system side unit to be incorporated, resulting in a short circuit. Therefore, the housing side of the disk device is provided with an insulating structure on the unit mounting surface to prevent a short circuit due to contact with the system side unit.

[0033]

【Example】

<Table of contents> 1. Overall structure and circuit block 2. Actuator 3. 3. Voice coil motor (VCM) (1) Assembly structure of voice coil motor fixed side (2) Expansion of coil effective length (3) Combination structure with actuator (4) Lock mechanism and stopper mechanism 4. 4. Flexible printed circuit (FPC) (1) Positioning and fixing of movable side of FPC (2) Noise prevention by FPC light pattern 5. Spindle motor 6. Base and cover 1. Overall Structure and Circuit Block FIG. 1 shows the internal structure of the disk device of the present invention with the cover removed, and FIG. 2 shows the I-I cross section of FIG.

1 and 2, the housing of the disk device of the present invention has a base plate 12 and a cover 10 divided into two parts. An actuator 26 is rotatably provided at a corner of the base plate 12. The actuator 26 is provided with the VCM 20 at the rear of the center of rotation, and the head 14-1 is mounted on the tip side. A disk as a recording medium rotated by the spindle motor 22 is provided for the actuator 26, and in this embodiment, three disks 30-1 to 30-3 are mounted.

Since the three disks 30-1 to 30-3 have both front and back surfaces as data surfaces, the total number of data surfaces is six. Six head units 14-1 to 14-6 are designated by the independent arm unit at the tip of the actuator 26 corresponding to the data surface. In addition, FIG. 2 shows the top head part 14-1 and the bottom head part 14
Only -6 is shown by a code | symbol, and the head parts 14-2 to 14-5 are arrange | positioned between them in order from the top as shown in the figure.

In each of the head portions 14-1 to 14-6, in this embodiment, a write head and a read head are provided, as will be made clear later. A magnetic head using a coil is used as the write head. On the other hand, an MR head using a magnetoresistive element is used as the read head. Actuator 2
In the base plate 12 adjacent to 6, the circuit board 60 using the FPC is arranged. The FPC connection band 62 is pulled out from the FPC board 60 and fixed to the side surface of the actuator 26. The head IC circuit 18 mounted on the FPC board 60 is provided on the FPC connection band 62.
There is formed a pattern for connecting the mounting circuit including the above and the six head portions 14-1 to 14-6 designated at the tip of the actuator 26.

The pattern on the FPC connection band 62 has a total of four connection patterns for each head portion, a pair of patterns for the read head and a pair of patterns for the write head. Further, the FPC connection band 62 has a VCM2
A pair of patterns for supplying a driving current to the moving coil of 0,
Further, the disks 30-1 to 30-3 are connected via the actuator 26.
A bias supply pattern for applying a bias voltage to 0-3 is formed.

Details of each part of the disk device of the present invention shown in FIGS. 1 and 2 will be clarified later. Figure 3
Shows an exploded view of the disk device of the present invention. In FIG. 3, first, three discs 3 are placed on the base plate 12.
A spindle motor 22 that rotatably supports 0-1 to 30-3 is assembled. Also, the disks 30-1 to 30
A circulation filter 55 is arranged near -3 to remove dust in the air flowing as the disk rotates. As the circulation filter 55, for example, a paper filter is used.

The actuator 26 is a VCM 20 or FPC.
It is assembled with the FPC boards 60 connected by the connection band 62. The VCM 20 is screwed and fixed in the screw holes 56 and 58 of the base plate 12 by screws 52 and 54. The FPC board 60 is screwed and fixed in the screw holes 68 and 70 of the base plate 12 by screws 64 and 66.

The packing 2 is provided on the upper portion of the base plate 12.
The cover 10 is attached via 8. The cover 10 has four screws 32, 34, 36 and 38 for the base plate 1
The screw holes 38, 40, 42, and 44 of 2 are fixed by screws. The cover 10 is provided with screw through holes 72, 74, 76, and a screw hole in the far right that is not visible. The spindle motor 22 has its fixed shaft screwed to the base plate 12 at the lower portion, and is attached and fixed to the screw hole 50 at the upper portion by the screw 46 inserted through the screw through hole 48 of the cover 10.

That is, the spindle motor 22 has a double-support structure in which it is fixed on the base plate 12 side and on both sides of the cover 10. Due to the both-end supporting structure of the spindle motor 22, the mounting rigidity with respect to the base plate 12 and the cover 10 is dramatically improved. Spindle motor 22
If the mounting rigidity is improved, it is possible to prevent the rotation shaft of the multilayer disc mounted with the discs 30-1 to 30-3 from swinging, and to significantly reduce the amount of off-track which causes an on-track error.

FIG. 4 shows an overall circuit block of the disk device of the present invention. 4, the disk device of the present invention is a disk enclosure 1000 having the structure shown in FIGS. 1 and 2, and a drive mounted on a printed circuit board accommodated from below in an opening of the base plate 12 at the bottom of the disk enclosure 1000. Controller 101
It consists of 2. The disk enclosure 1000 is provided with head units 14-1 to 14-6 corresponding to the six data surfaces of the three disks 30-1 to 30-3.

In each of the head portions 14-1 to 14-6,
Read heads 15-1 to 15-6 and write head 16-
1 to 16-6 are integrally provided. Light head 1
6-1 to 16-6 use magnetic heads, and read heads 15-1 to 15-6 use MR heads using magnetoresistive elements. In the MR head, it is necessary to flow a specified bias current during the read operation.

The read heads 15-1 to 15-6 and the write heads 16-1 to 16-6 are connected to the head IC circuit 18 to switch the heads and bias the read heads 15-1 to 15-6 using the MR head. Supply voltage. Further, the disk enclosure 1000 is provided with a spindle motor 22 for rotating the disk and a VCM 20 for positioning the head.

The drive controller 1012 is provided with an MPU 1024 which functions as a control unit. MPU1
For the 024 bus 1058, a read-only EPROM 1026 used as a program memory and a readable / writable DRAM 1028 are provided. EPROM 102
A start-up program (boot program) used at the time of start-up accompanying the power-on of the disk device is fixedly stored in the reference numeral 6. The DRAM 1028 has an EPROM 10
The start-up program 26 stores a control program (microprogram) downloaded from the disk on the side of the disk enclosure 1000 after the start-up of the disk device is completed.

The bus 1058 of the MPU 1024 further has
An interface circuit 1030 and a buffer memory 1032 for data transfer are provided. Interface circuit 10
For example, SCSI is used as 30, and commands and data necessary for external storage are exchanged by using, for example, a notebook computer equipped with the disk device of the present invention as a host computer. Furthermore, a cache controller 1031 and a cache memory 1033 are provided.

The spindle motor 22 provided in the disk enclosure 1000 is controlled by the PWM circuit 103.
4 and the driver 1036. The head positioning control of the VCM 20 provided in the disk enclosure 1000 is performed by the DA converter 1038 and the driver 1040. In any case, MPU102
Drive control of the spindle motor 22 and positioning control of the VCM 20 are performed by program control according to 4.

The drive controller 1012 is provided with an AGC amplifier 1042, an equalizer circuit 1044, a maximum likelihood detection circuit 1046, an encoder / decoder 1050, and a hard disk controller 1052 as a read / write system. Furthermore, as a servo system for head positioning control,
Peak hold circuit 1054, AD converter 1055
Also, a servo frame demodulation circuit 1056 is provided.

In the read operation, the head IC circuit 18 is sent by a switching signal from the hard disk controller 1052.
Is switched to, for example, the read head 15-1 side of the head unit 14-1, and the analog read signal (read signal) from the read head 15-1 is input to the AGC amplifier 1042. The analog read signal is amplified by the AGC amplifier 1042, waveform-equalized by the equalizer circuit 1044, and given to the maximum likelihood detection circuit 1046 and the VFO circuit 1048. The VFO circuit 1048 generates a reference clock synchronized with the read signal during the read operation.

Maximum likelihood detection circuit 1046 and VFO circuit 1
The output of 048 is given to the encoder / decoder 1050 which is switched to the decoder side in the read state, the read data is restored while synchronizing the clock, the hard disk controller 1052 performs formatter processing, and then transferred to the buffer memory 1032. It afterwards,
The read data is transferred to the host device via the interface circuit 1030.

On the other hand, in the write operation, the write data transferred to the buffer memory 1032 via the interface circuit 1030 is supplied via the hard disk controller 1052 to the encoder / decoder switched to the encoder during the write operation. To do. The encoder / decoder, for example, converts the write data into a 2-7 run length code, adds an ECC check code, and supplies the write data to the write head 16-1 via the head IC circuit 18. Servo information according to the sector servo system is recorded on each of the data surfaces provided in the disk enclosure 1000. 2. Actuator FIG. 5 shows an embodiment of an actuator which is used in the disk device of the present invention and which is balanced in the optimum state. In addition, FIG. 6 shows an actuator before the balance adjustment of the present invention is adopted.

In FIG. 5, the actuator 2 of the present invention is shown.
6 is an arm portion 80-1 extending toward the disk centering on a shaft mounting portion 85 on which a cylindrical rotating shaft 86 is mounted.
Gimbal spring 82-connected to the tip of 0-1 with pin 84-
The head unit 14-1 is attached via the head 1. The point 94 of the head portion 14-1 becomes the reference position (center of the head) that gives the head gap. Behind the shaft mounting part 85 is a VCM
A coil support plate 88 integrally equipped with 20 movable coils 90 is mounted.

In the present invention, the shaft mounting portion 85 and the arm portion 80-1 of the actuator 26 are formed by machining an aluminum extruded block. Also, the shaft mounting portion 8
As the coil support plate 88 attached to the back of 5,
It is molded integrally with the movable coil 90 using a liquid crystal polymer. Here, the arm portion 80-1 is the uppermost arm portion in the actuator 26 shown in FIG. 2, and the remaining three arm portions 80-2 to 80-4 are formed below it. Of these, the lowermost arm portion 80-4 is similar to the uppermost arm portion 80-1 in gimbal spring 82.
Although the head portion 14-6 is supported via -6, the two arm portions 80-2, 80-3 between them are provided with gimbal springs 82-2, 82-3 and gimbal springs 82-4, 82 on both sides. -5, each of which has a head 14 at the tip.
-2 to 14-5 are attached.

Further, the actuator 2 of the present invention shown in FIG.
6, the mounting portion of the gimbal spring 82-1 is bent at the tip of the arm portion 80-1 toward the center of the disc 30-1 to make an angle, as is apparent from FIG.
As a result, the movable coil 90 is used as the actuator 26.
It has an asymmetric shape when viewed from the side. The asymmetrical shape in which the tip of the arm portion 80-1 has an angle maintains the harboring relationship as much as possible by pressing the tilt of the write head and read head with respect to the track direction in the circumferential direction of the disk with respect to the rotation of the actuator 26. To do.

Actuator 2 having such an asymmetrical shape
6, the rotation center 86, the geometrical center 96 of the movable coil 90, and the head portion 14-
The center of the head 94, which is the head gap position of No. 1, is arranged on a straight line 95. When adjusting the balance of the actuator 26 in the conventional shape shown in FIG. 6, the center of gravity of the actuator 26 is aligned with the center of rotation 92. In order to match the center of gravity of the actuator 26 with the center of rotation 92, a thick portion is formed in each member on the head side and the coil side in order to provide weight for balance adjustment. As a result, the actuator 26 as a whole is formed. As a result, the VCM 20 increases the inertia of the actuator 26.

On the other hand, in the actuator 26 of the present invention shown in FIG. 5, the head 14-
1-side center of gravity position 98 and moving coil 90-side center of gravity position 10
Ask for 0. When the head side center of gravity position 98 and the coil side center of gravity position 100 are obtained in this way, for example, the coil side center of gravity position 100 is located on a straight line 102 connecting the rotation center 92 and the head side center of gravity position 98, The position of the coil support plate 88 with respect to the rotary bearing portion 85 of the actuator 26 is adjusted and positioned.

When the actuator of FIG. 5 according to the present invention is viewed in comparison with the conventional actuator of FIG. 6, the coil support plate 88 having the movable coil 90 shows a conventional straight line 95.
On the straight line 102 connecting the center of rotation 92 rotated clockwise from the upper position and the center of the head side 98, the center of gravity of the coil side 1
It can be seen that the shape is such that 00 is positioned.

Here, the coil support plate 88 is formed with through holes 87-1 and 87-2. The through hole 87-1 on the straight line 102 is provided for adjusting the balance in the actuator longitudinal direction with respect to the rotation center 92.
In addition, since the coil support plate 88 has an asymmetrical shape in this embodiment, the through hole 87-2 is adjusted so that the coil center of gravity position 100 associated with this asymmetrical shape is located on the straight line 102 passing through the center of the movable coil 90. It's empty.

More specifically, first, the weight on the head side provided with the arm 80-1 and the gimbal spring 82-2 is determined, and the through hole 87-1 and the through hole 87-2 are provided for the weight on the head side. Set the weight on the coil side so that the weight is the same. Then, the head-side center of gravity position 98 and the coil-side center of gravity position 100 may be obtained and arranged so as to be aligned on a straight line 102 passing through the rotation center 92.

FIG. 7 shows an embodiment of the rotary shaft 86 provided on the shaft mounting portion 85 of the actuator 26 of the present invention shown in FIG. In FIG. 7, the rotary shaft 86 is a cylindrical member,
The fixed shaft 104 is provided inside, and the screw portion 110 provided at the lower portion of the fixed shaft 104 is screwed and fixed to the lower yoke 24 functioning as the bottom plate shown in FIG. Further, a screw hole 112 is formed on the fixed shaft 104, and the VCM 20
Is fixed by screws through a yoke forming the upper part of the.

Grooves 10 are provided at two locations on the fixed shaft 104.
6, 108 are formed. A plurality of bearings 114 and 116 are arranged in the grooves 106 and 108. Bearing 1
An outer race 118 is provided on the outer side of 14, and an outer race 120 is provided on the outer side of the bearing 116. Each of the outer races 118 and 120 is assembled with screws 122, 124, 126 and 128 as shown in the drawing.
It is fixed to the rotary shaft 86. A spring 130 is incorporated between the outer races 118 and 120. Further, the seal plate 1 is provided outside the bearings 114 and 116.
32 and 134 are fixed.

With the shaft assembly shown in FIG. 7 completed,
The screws 122, 124, 126, 128 are removed.
As a result, the outer races 118 and 120 are pressed in the vertical direction by the spring 130, and the inner tapered surface of the outer race is stipulated by preloading the ball bearing 1.
It will be pressed against 14,116. FIG. 8 shows I of FIG.
The I-II cross section is shown. As shown in FIG. 8, the fixed shaft 104
With respect to the lower groove 108, a ball bearing 116 is arranged in a ring shape with no gap to form a full ball structure.

The bearing structure shown in FIG. 7 is characterized in that the ball bearings 114 and 116 are not provided with inner races. That is, in the conventional bearing structure of the disk device, the bearing structure having the inner race and the outer race is used. However, with the downsizing of the disk device, the bearing structure of the actuator 26 also becomes a motor, and in the bearing using the inner race and the outer race, the diameter of the ball bearing becomes extremely small, and the wear performance of the ball bearing and the rigidity with respect to impact are reduced. Will decrease.

Therefore, in the present invention, as shown in FIG. 7, the groove 10 is directly provided on the fixed shaft 104 without providing the inner race.
6 and 108 are provided to replace the inner race. By not providing the inner race in this way, even if the shaft structure is downsized, ball bearings having a large diameter can be used as the ball bearings 114 and 116 to be used. Therefore, the wear resistance of the ball bearings 114 and 116 and the rigidity against impact are significantly increased as compared with the case where the inner race is used.

Further, as shown in FIG. 8, the ball bearings 114 and 116 have a full ball structure, so that the load applied to each ball bearing can be reduced and the impact resistance can be improved. FIG. 9 shows a manufacturing state of the arm block including the shaft mounting portion 85 and the arm portions 80-1 to 80-4 in the actuator 26 of the present invention shown in FIG. In the conventional disk device,
The arm block of the actuator is molded by aluminum die casting. Therefore, there is a problem that nests are likely to be formed inside the block, and the nests are likely to be deformed due to heat or due to aged deterioration, and off-track is likely to occur.

In the actuator of the disk device of the present invention, as shown in FIG. 9, the shaft hole 138 and the cavity 140 are formed.
The mold material 136 provided with is obtained by extrusion molding of aluminum.
Then, after cutting out as shown by the imaginary line, the arm block 142 is created by machining, and the actuator 26 shown in FIG. 5 is assembled. By using the extruded arm block 142 in this way, off-track due to thermal deformation and aged deformation due to a cavity generated in the conventional aluminum die casting is unlikely to occur, and the block obtained by extrusion molding and machining is Since there is almost no variation in the shape of parts, stable actuator performance can be realized. 3. Voice coil motor (1) Assembly structure of voice coil motor fixed side FIG. 10 shows a VCM 20 used for driving an actuator.
12 is an exploded view of the fixed side of FIG. 11, showing the assembled state. The fixed side used in the VCM 20 of the present invention is composed of the lower yoke 24 to which the lower magnet 154 is fixed and the upper yoke 152 to which the upper magnet 156 is fixed. As shown in FIG. 12A, the lower yoke 24 has a fan-shaped lower magnet 154 adhered and fixed to the upper surface thereof, and screw through holes 162 and 164 provided at two positions. Here, the through holes 162 and 164 are for attaching the stopper portion, and have a double-sided hole shape to prevent rotation.
Further, a receiving hole 168 for positioning by fitting with the upper yoke 152 is opened on the side of the through hole 164.

Further, a latch piece 200 is formed on the left side of the lower magnet 154 by cutting out the lower yoke 24, and a latch magnet 198 is mounted inside the latch piece 200. The latch piece 200 and the latch magnet 198 allow the head portion provided at the tip of the actuator to be latched at the innermost position of the disk, which will be made clear later. 12B is a side view of the lower yoke 150, and FIG. 12C is a bottom view of the lower yoke 24.

FIG. 13A shows the upper yoke 1 shown in FIG.
52 is viewed from the lower side, and a side view thereof is shown in FIG. An upper magnet 156 is fixed to the lower surface of the upper yoke 152 with an adhesive or the like. The upper magnet 156 is arranged so as to overlap the lower magnet 154 shown in FIG. 12A with a predetermined gap. Upper magnet 1
On both sides of 56, working holes 158 and 160 used when fixing the lower yoke 24 located on the lower side to the base plate 12 side by screwing are formed. Further, a through hole 170 for screwing at the rotation center of the actuator is provided.

Standing pieces 174, 176, 178 bent downward are provided at three locations on the upper yoke 152. Of these, a protrusion 166 that fits into the receiving hole 168 of the lower yoke 24 of FIG. 12 is formed in the lower portion of the standing piece 176.
The height of the standing pieces 174 and 178 and the standing pieces 176 excluding the protrusion 166 is such that the movable coil 90 on the actuator side between the lower magnet 154 and the upper magnet 156 when the upper yoke 152 is assembled to the lower yoke 24 is housed. Determine the gap spacing.

Base plate 1 of such VCM 20
When assembling the second yoke 2, first, an assembly of the lower yoke 24 and the upper yoke 152 is prepared. That is, the lower yoke 24
The lower magnet 154 is provided on the upper yoke 15
Since the upper magnet 156 is provided in 2,
As shown in FIG. 10, the protrusion 166 at the tip of the standing piece 176 of the upper yoke 152 is aligned and fitted into the receiving hole 168 of the lower yoke 24. Lower yoke and upper yoke 152
Due to the attractive force of the lower magnet 154 and the upper magnet 156, they are integrally assembled and fixed as shown in FIG. Therefore, when the magnetic circuit is formed by assembling the yoke, screws, adhesives, caulking, etc. are not required unlike the conventional case, and the lower yoke 24 and the upper yoke 152 can be fixed in the assembled state only by the attractive force of the magnet.

After the upper and lower yokes have been assembled, FIG.
As shown in FIG.
On the other hand, the screws 52 and 54 are inserted from the working holes 158 and 160 of the upper yoke 152 through the through holes 162 and 164 of the lower yoke 24 and fixed by a driver or the like. (2) Enlargement of coil effective length FIG. 14 shows an arrangement relationship between a magnet and a movable coil in the VCM of the present invention. That is, in FIG. 14, V
It shows a state in which the upper yoke of the CM is removed.
The movable coil 90 mounted on the coil support plate 88 provided on the rear portion of the rotary shaft 86 of the actuator 26 includes a lower magnet 154 and an upper magnet 15 positioned above.
The left and right coil portions 90-1 and 90-2 in the longitudinal direction of the actuator 26 are portions of the coil effective length for obtaining the rotational torque with respect to the magnetic flux generated during the period.

On the other hand, regarding the coil portions 90-3 and 90-4 before and after the movable coil 90, no rotational torque is obtained even if the magnetic flux passes through these portions, and the actuator 2
6 generates thrust force in the longitudinal direction. Therefore, the front and rear coil portions 90-3 and 90-4 are coil portions that do not generate rotational torque. In the conventional VCM, the magnet outer ends 178 and 184 of the lower magnet 154 and the upper magnet 156 in the front-rear direction are attached to the movable coil 9.
0 to match the coil inner ends 180, 182 in the front-rear direction,
The magnet is prevented from being applied to the coil portions 90-3 and 90-4 that do not contribute to the generation of the rotating torque.

On the other hand, in the VCM 20 of the present invention, as shown in FIG. 14, the lower magnet 154 is attached to the coil inner ends 180 and 182 of the movable coil 90 in the front-rear direction.
The magnet outer ends 178 and 184 of the upper magnet 156 (not shown) are enlarged so as to slightly overlap the front and rear coil portions 90-3 and 90-4 as shown by the broken line.

FIG. 15 shows a cross section in the longitudinal direction of the actuator of FIG. As is apparent from this cross-sectional view, the magnet outer end 1 of the lower magnet 154 and the upper magnet 156 is different from the coil inner end 180 outside the movable coil 90.
78 and 186 are inserted into the front and rear coil portions by ΔL. Similarly, with respect to the inner coil inner end 182, the magnet outer ends 184 and 188 of the lower magnet 154 and the upper magnet 156 are inserted by ΔL.

FIG. 16 shows the operation when the magnet ends are slightly overlapped with the front and rear coil portions. The magnetic flux density of the lower magnet 154 and the upper magnet 156 passing through the left and right coil effective length portions of the movable coil 90 is lowered by the external leakage magnetic flux at the outer ends of the magnet reaching the front and rear portions of the coil. As a result,
Even if the front and rear magnet widths physically match the lengths of the left and right coil portions, the effective length is substantially shortened due to the decrease in the magnetic flux density at the ends.

On the other hand, as shown in FIG. 16, when the magnet outer ends 178 and 186 are enlarged so as to overlap the coil inner end 180 and overlap, the coil effective lengths of the left and right coil portions are exceeded. Magnetic flux leaks to the outside between the magnets at the position, and uniform magnetic flux density can be obtained for all of the effective lengths of the physically left and right coil portions. As a result, the physical coil effective length and the coil effective length at which the magnetic flux density becomes constant are almost the same, and the effective length of the coil can be substantially increased compared to the conventional one.
The rotation torque generated by the VCM can be increased.

On the other hand, the amount ΔL of overlapping the outer end of the magnet with the front and rear coil portions is determined in consideration of the thrust force of the actuator generated when the magnetic flux passes through the front and rear coil portions. 17A shows the relationship of the rotational force F with respect to the overlap amount L for the coil portion at the outer end of the magnet, and FIG. 17B shows the relationship of the thrust force F2 with respect to the overlap amount L. Rotational force F of VCM
1 is the overlap amount L = 0, that is, F is the same as the conventional case.
11, the rotational force increases as shown by the curve 190 when the amount of overlap at the outer end of the magnet is increased, and the torque saturates at a certain position.

On the other hand, as shown by a curve 192, the thrust force F2 has a characteristic that the initial value is the overlap amount L = 0 and the thrust force F2 is also increased with the increase of the overlap amount L and finally saturated. Become. If the thrust force F2 becomes too large, the rotation of the actuator 26 becomes stagnant, and the inertia increases. Therefore, thrust force F2
The overlap amount ΔL is determined at a position where the threshold value Fth is suppressed.

When the thrust force F2 is suppressed to the threshold value Fth in this way, the overlap amount ΔL determined by the point 194 on the curve 192 is obtained. The rotational force at this overlap amount ΔL becomes F12 given by the point 196 of the characteristic 190, and the rotational force of the VCM can be increased. (3) Assembly Structure with Actuator FIG. 18 shows an assembly structure of the actuator 26 with respect to the lower yoke 24 functioning as the bottom plate shown in FIG. The lower yoke 24 of the VCM 20 extends to a portion of the rotary shaft 86 of the actuator 26, and a hole 172 is provided in that portion. In the hole 172, the actuator 2
Ball bearings 114, 11 inside the rotary shaft 86
6, the shaft portion 110 below the fixed shaft 14
Is press-fitted and fixed.

Further, a stopper portion 196 for positioning the coil support plate 88 of the movable coil 90 at the rear portion of the actuator 26 is integrally provided on the lower yoke 24 functioning as a bottom plate by screwing.
Further, a latch magnet 198 is arranged at the position of the latch piece raised by cutting out the lower yoke 24. Here, a screw 54 for fixing the stopper portion 196 to the lower yoke 24
2 has a function of fixing the lower yoke 24, which functions as a bottom plate, to the base plate 12 by being screwed and fixed to the screw hole 58 of the base plate 12 of FIG. 2 located further below through the through hole 164.

As described above, by mounting the actuator 26 and the stopper portion 196 using the lower yoke 24 on the fixed side of the VCM 20 as a bottom plate, the fixed side of the VCM 20 and the actuator 26 are separately prepared, and are individually mounted on the base plate 12, for example. Compared with mounting and fixing to V
The positional accuracy of the fixed side of the CM 20 and the actuator 26 can be greatly improved. (4) Lock Mechanism and Stopper Mechanism of Actuator FIG. 19 shows the lock mechanism and the stopper mechanism of the actuator according to the present invention from behind the movable coil provided in the actuator. A stopper step portion 203 is formed at the rear right end of the coil support plate 88 of the actuator, and the latch plate 20 is provided near the stopper step portion 203.
2 is provided. As shown in FIG. 20, the latch plate 202 is a U-shaped bent member made of a magnetic material such as iron, and is integrated when the coil support plate 88 made of liquid crystal polymer is molded. It is embedded and fixed in.

On the other hand, from the lower yoke 24, the latch piece 200
And the latch magnet 198 is positioned and fixed inside the latch piece 200. The coil support plate 88 of the actuator is the latch plate 2 shown in the figure.
02 is held by receiving a suction force by the latch magnet 198 at a position facing the end surface of the latch piece 200. On the right side of the latch piece 200 including the latch magnet 198, a stopper portion 196 is arranged by screwing the screw 54 into the screw hole 58 of the base plate 12. The stopper portion 196 has a rubber contact portion formed on its surface,
The coil support plate 88 contacts the rubber portion.

The lock mechanism of the actuator using the latch magnet 198, the latch piece 200 and the latch plate 202 shown in FIG. 19 brings the head to the innermost position by the VCM 20 when the disk device of the present invention is cut off and stopped. The actuator is locked by a magnetic attraction force during the stop operation for returning, and in this actuator locked state, the head is located in the contact start / stop area (CSS area) of the innermost disk and comes into contact with the disk surface. Head starts contact
If the head is placed in contact with the stop area for a long period of time, the head is attracted to the disk surface, and the operation of releasing the attraction of the head is required when the disk device is powered on next.

In order to release the adsorption of the head in the stopped state, in the disk device of the present invention, the operation of further driving the head to the inner side is performed from the locked state when the power is turned on. This is called a compressing operation for releasing the head suction. When the actuator is further driven from the lock position to the inner side, the stopper portion 196 is made of rubber, so that the rubber is deformed and the actuator moves further to the inner side.
This allows the contacting head to be separated.

FIG. 21A shows a state where the latch plate 202 provided on the coil support plate 88 of the actuator approaches the latch piece 200. The latch magnet 198 provided on the right side of the latch piece 200 forms a magnetic circuit indicated by an arrow on the end surface of the latch piece 200 by forming a magnetic circuit by the upright latch piece 200.

If the latch piece 200 is not present,
A spatial magnetic circuit is formed as shown on the right side of the latch magnet 198, and the attraction force gradually increases as the latch plate 202 approaches the latch magnet 198, and becomes maximum at the relative position of the latch magnet 198. Therefore, when the latch 200 is not provided, the movement of the actuator when the inner side is reached is affected by the formation of the spatial magnetic circuit from the latch magnet 198.

On the other hand, in the present invention, the latch piece 2
By providing 00, the latch magnet 198 is not affected until the latch plate 202 comes into the end surface of the latch piece 200, as shown in FIG. Then, as shown in FIG. 21B, the latch piece 200
The magnetic attraction force becomes maximum when the latch plate 202 faces the end face of the latch magnet 198 at this position.
The locked state is obtained by the magnetic attraction force of the actuator.

FIG. 22 shows the stopper portion 196 shown in FIG.
Shows the details of. The stopper portion 196 is a metal holder 20.
A hard rubber layer 208 is formed on the outer periphery of the hard disk 4, and a soft rubber protrusion 210 is provided so as to slightly project from the hard rubber layer 208 on the right side with which the coil support plate 88 abuts. FIG. 23 shows a section taken along line III-III in FIG. Holder 20
The hard rubber layer 208 formed around 4 has a circular cross section, whereas the soft rubber projection 210 is formed so as to project in a state in which the center is offset to the right.

FIG. 24A shows the holder 204 of the stopper portion 196 taken out. The holder 204 has fitting portions 205 and 206 having upper and lower flanges, for example, as shown in FIG.
As shown in the bottom view of (B), the fitting portion 206 has a so-called double chamfered shape with both sides cut off. This holder 2
The fitting portion 206 having the double chamfered shape of 04 is the through hole 1 of the lower yoke 24 that also has the double chamfered hole shown in FIG.
It is fitted in 62 in a non-rotating state. Further holder 204
22 has a through hole 212 formed therethrough. As shown in FIG. 22, the screw 54 is inserted into the through hole 212 and the upper yoke 1
It is threaded through the work hole 160 of 52 and fixed in the screw hole 58 of the base plate 12.

As described above, since the stopper portion 196 is provided with the soft rubber protrusion 210 and the hard rubber layer 208 on the contact surface of the coil support plate 88 of the actuator,
In the locked state by the latch magnet 198, the latch piece 200, and the latch plate 202 shown in FIG. 9, the soft rubber protrusion 210 is lightly hit. When the disk device is powered on and started up from the locked state of the actuator, the coil support plate 88 pushes the soft rubber protrusion 210 by driving the VCM in the inner direction and slightly moves to a position where it abuts the hard rubber layer 208. It is possible to move, and thereby the head suction can be released.

Further, since the stopper mechanism is provided on both the inner side and the outer side and is fixed by screwing, the screw may be loosened when the actuator repeatedly collides. Therefore, in the present invention, the loosening of the screw is prevented by providing the collision portion of the actuator with the stopper with an angle that generates a force to tighten the screw at the time of collision.

FIG. 25 shows a state in which the actuator 26 is brought into contact with the stopper portion 196 on the inner side. In this case, the actuator 26 hits the stopper portion 196 at the collision surface 222 on the right side of the coil support plate 88. Here, when the contact position with respect to the stopper portion 196 is 220, a straight line 224 connecting this contact point 220 and the rotation center 96.
A force 226 in a direction orthogonal to is applied to the stopper portion 196.

This force 226 is at the center 1 of the stopper portion 196.
98 is off, and a clockwise force indicated by an arrow is applied to the stopper portion 196. Here, since the right screw is used for fixing the stopper portion 196, the screw is tightened by the clockwise force of the force 226 due to the collision and is not loosened. In order to generate the force 226 for generating such a rotational force, the inclination of the collision surface 222 with respect to the straight line 224 passing through the rotation center 96 may be set to the horizontal angle α.

FIG. 26 shows a state of collision with the stopper portion 218 when the actuator 26 moves to the outermost side. In this case as well, the direction of the collision surface 232 of the coil support plate 88 with respect to the stopper portion 218 is set to the contact point 2
The force 234 indicated by an arrow can be applied to the stopper portion 218 by setting the angle 230 with respect to the straight line 230 connecting the 28 and the rotation center 96.

Since this force 234 deviates from the rotation center 215 of the stopper portion 218, a clockwise force indicated by an arrow is applied. Therefore, since a right screw is used for the stopper portion 218, the force 23
In 4, the screw receives a rotational force in the tightening direction and can be prevented from loosening. 4. Flexible Printed Circuit (FPC) (1) Positioning and Fixing of FPC Circuit Moving Portion In the disk device of the present invention shown in FIG. 1, an FPC connecting band 62 which is a moving portion extending from the fixedly arranged FPC board 60 to the actuator 26. Regarding the fixing of the part, since the band part has a structure in which there is a gap in both the height direction and the width direction, the FPC connection band 62
Positioning work on the fixed side of the FPC board 60 is important.

If there is an error in the assembling position in this positioning work, the bending shape of the FPC connecting band 62 that changes its bending state according to the movement of the actuator 26 becomes abnormal,
There is a risk of contacting components such as ICs and resistors mounted on the FPC board 60. Further, if the fixing is incomplete, the movement of the actuator 26 cannot be followed and the FPC connecting band 62 flaps, and an abnormal external force due to deformation is applied to the actuator 26 at the same time as contacting with other parts, which deteriorates responsiveness. .

Therefore, according to the present invention, the FPC connection band 62 extending to the actuator 26 can be moved to the FP with one touch.
A structure for positioning and fixing on the C board 60 side is realized. Figure 2
7 shows a connection state between the FPC board 60 and the actuator 26 of the present invention shown in FIG. 1 by the FPC connection band 62. First, referring to the exploded view of FIG. 28, the FPC
The structure on the substrate 60 side will be described. The FPC board 60 is adhesively fixed on the metal board plate 24 using the double-sided adhesive sheet 242. The FPC board 60 has a head IC on the surface.
A circuit component including the circuit 18 is mounted, the band lead-out portion 265 is integrally erected on the side surface, and the FPC connection band 62 is integrally drawn from the right end portion thereof.

The connection pattern for the head on the FPC board 60 is formed by printing as a circuit pattern on the FPC connection band 62 via the band lead-out portion 265. In addition, the protrusion 26 is provided on the side surface of the band drawer 265.
8 are provided. Further, the FPC board 60 is provided with a connector hole 264 in which a plurality of pins used for connector connection are arranged.

The double-sided adhesive sheet 242 has a thin resin film coated on both sides with an adhesive, and has a through hole 25.
6, 258 and rectangular holes 254 for connectors. The metal substrate plate 240 has a shape facing the FPC substrate 60, and has through holes 250 and 252 and a rectangular hole 248 for a connector. Furthermore, FPC on the side
A J-shaped receiving portion 248 that supports the connection pattern portion 265 of the substrate 60 is provided.

This J-shaped receiving portion 248 has a cutout 25 on the lower side.
It is separated by 4, and thus has a cantilever spring structure. In addition, a fitting hole 246 is provided substantially in the center of the band support portion 244. The protrusions 268 and 270 provided on the plate spring portion 262 of the band pressing member 260 are inserted into the upper and lower portions of the fitting hole 246 to be positioned. FIG. 29 shows FIG.
The metal substrate plate 240 shown in FIG.

FIG. 30 is a double-sided adhesive sheet 2 shown in FIG.
FPC board 6 for board plate 240 using 42
FPC pulled out to the actuator side after assembly of 0
The state of assembling of the band pressing member 260 for positioning and fixing the connection band 62 is shown. The band pressing member 260 has the structure shown in FIG. Further, FIG. 32 is a perspective view of the right and left sides of the band pressing member 260.

First, the band pressing member 260 is shown in FIG.
As shown in (A), it has a leaf spring shape in which the rear part is folded in two. One of the leaf spring parts 262 folded in two is shown in FIG.
An inverted J-shaped holding portion 272 is formed at the tip, which is fitted into the J-shaped receiving portion 248 of the band supporting portion 244 of the substrate plate 240 shown in FIG. The leaf spring portion 262 reaching the inverted J-shaped pressing portion 272 at the tip is formed after being bent at an angle outward from the parallel portion on the double-folding side, and has a spring property that spreads outward at this portion. There is. A protrusion 274 is formed at the tip of the other leaf spring portion 264 that is folded in two.
Is formed. The protrusion 274 is formed in the fitting hole 24 formed in the band supporting portion 244 of the substrate plate 240 shown in FIG.
It is formed at a position where it fits in 6. FIG. 31B is a side view of the band pressing member 260 seen from the plate spring portion 264 side. There is.

Further, the plate spring portion 2 of the band pressing member 260 is
On the 62 side, a positioning piece 266 is provided at a position below the root of the double-fold, and positioning pieces 268, 270 are provided at upper and lower portions of the inverted J-shaped pressing portion 272 at the tip. As is clear from FIG. 32 (A), the base positioning piece 266 supports and positions the lower end surface of the FPC connection band 62 drawn to the outside. On the other hand, the inverted J-shaped pressing portion 272
The positioning pieces 268 provided above and below the front of the
It has a function of positioning the base of the PC connection band portion 62 and suppressing vertical movement. Therefore, the FPC connection band portion 62
Does not flutter in the device, and the actuator drive in consideration of the reaction force of the FPC connection band portion 62 can be easily controlled.

FIG. 32B clearly shows the state of the leaf spring portion 264 on the outer side of the two-fold, in which the protrusion 274 at the tip positions the board plate 240 with respect to the fitting hole 246 and the leaf spring portion 262 and The gap between the substrate plate 2
It is fitted into the band support portion 244 of 40 and fixed by the spring property. FIG. 33 (A) shows a plan view of a completed assembled state by mounting the band pressing member 260, and FIG. 33 (B) shows a side view thereof. The band pressing member 260 supports and fixes the FPC board 60 by sandwiching the root portion of the FPC connection band 62 inside the band support portion 244 which is the upright portion of the board plate 240 supporting the FPC board 60 from below. Using the positioning piece 268 as a fulcrum on the fixed side, the FPC connection band 62 is deformed by the movement of the actuator.

As described above, the mounting of the band pressing member 260 enables the positioning with respect to the fixed side of the FPC connection band 62 with one touch, and the assembly is extremely simple. In addition, since the position of the fixing portion is uniquely held at a predetermined position by the assembly of the band pressing member 260, there is no variation at the time of assembly. (2) Noise Prevention by FPC Write Pattern Since the disk device of the present invention uses the MR head as the read head, it is necessary to flow a bias current in the read head during the read operation. For this reason, the head core has an electric potential, and when the core comes into contact with the disk medium, a current flows, which may destroy the core. Therefore, a potential is also applied to the disk side to prevent destruction due to contact with the head core.

In order to give the disc a bias potential,
In the present invention, the dedicated line is not required by providing the bias supply pattern in the FPC connection band 60. Further, when the MR head is used as the read head, the read signal becomes weaker than that of the conventional magnetic head, and in particular, F
External noise is induced in the circuit pattern of the PC connection band 62, and the S / N ratio is greatly reduced.

Therefore, in the present invention, the arrangement of the connection pattern for each head formed on the FPC is devised to prevent noise from being mixed into the lead pattern. That is,
Since the head portion of the present invention is equipped with the write head using the magnetic head and the read head using the MR head, four connection patterns are used per head. Two of the write patterns are not used during the read operation. Therefore, attention is paid to a write pattern that is not used at the time of reading, and by making it play the role of a ground pattern at the time of a read operation, noise mixing in the read pattern is prevented.

FIG. 34 shows the pattern structure of the FPC connection band 62 used in the present invention, which has the arrangement of the bias supply pattern and the write pattern for noise prevention. FPC
The connection band 62 has six heads 1 on the actuator side.
4-1 to 14-6 are connected to the fixed side circuit unit. Here, the six head portions 14-1 to 14-6 are the head portions 1
As represented by 4-1 and 14-6, read heads 15-1 and 15-6 using MR heads and write heads 16-1 and 16-6 using magnetic heads are provided. Then, each of the head portions 14-1 to 14-6 has the head 1
Four patterns are formed for each piece.

In the present invention, the patterns of the head portions 14-1 and 14-6 located on both sides are arranged so that the patterns for the write heads 16-1 and 16-6 are located on the outermost side. ing. For example, the head unit 14
Taking -1 as an example, the two outer patterns 300-1,
302-1 is a write pattern of the write head 16-1, and the read patterns 304-1 and 306-1 for the read head 15-1 are arranged inside thereof.

This point also applies to the head portion 14-6 located on the outer side of the opposite side. That is, the write patterns 300-6 and 302-6 of the write head 16-6 are arranged at the outermost positions of the circuit pattern, and the read patterns 304-6 and 306 of the read head 15-6 are arranged inside thereof.
-6 is placed. Remaining head parts 14-2 to 14-
5, the read pattern and the write pattern may be located at either position, but in this embodiment, the head portions 14-2 and 14-3 are in the order of the write pattern and the read pattern from the outside, while the head 14 -5
As for 14-4, the write pattern and the read pattern are sequentially arranged from the opposite outer side.

The write patterns provided for the heads 14-1 to 14-6 are selectively connected to the write amplifier 316 via the select circuit 314 on the fixed side. The select circuit 314 selects one of the write head lines according to the head selection signal, and the write amplifier 31
6 is connected. The write amplifier 316 has, for example, the circuit configuration shown in FIG. The write amplifier 316 is a bridge circuit using transistors 318, 320, 322 and 324, and connects the write head 16 between the transistors 318 and 320 and between the transistors 322 and 324. The transistors 318, 320, 324, 322 are
It is turned on / off by control signals E1, E2, E3, E4.

For example, when the transistors 318 and 324 are turned on by the control signals E1 and E4, the write head 16
A current flows in the direction indicated by the solid arrow. Further, when the transistors 322 and 320 are turned on by the control signals E2 and E3, a current indicated by a dashed arrow can be passed through the write head 16. Further, if only the transistors 318 and 322 are turned on by the control signals E1 and E2, the power supply voltage V
cc can be applied to the write head 16. Furthermore, when only the transistors 320 and 324 are turned on by the control signals E3 and E4, the write head 16 can be connected to the ground potential.

In the embodiment shown in FIG. 34, the transistor 3 of the write amplifier 316 shown in FIG. 35 is used during the read operation.
All 18, 320, 322, and 324 are turned off, and the light patterns arranged on both sides are electrically released. FIG. 36 shows the noise prevention effect in the read operation when the write patterns on both sides are released.
If the read operation of the read head 15-6 of the lower head section 14-6 is performed, the write head 16-6
The write patterns 300-6 and 302-6 of No. 3 are placed in the released state by the write amplifier 316. At this time, if noise from the external noise source 322 is added, capacitors 324, 326, 32 due to the floating capacitance are provided between the noise source 322 and the lead pattern 304-6 as shown in the figure.
8 is formed.

Therefore, the noise voltage from the external noise source 322 is transferred to the three capacitors 324, 326, 328.
Is divided into. That is, with respect to the change of the noise voltage ΔV of the external noise source 322 shown in FIG.
Lead pattern 304 by partial pressure by 4, 326, 328
The noise voltage applied to −6 is (1/3) of FIG. 37 (B).
It becomes ΔV, and the noise voltage can be reduced to 1/3.

FIG. 38 shows another embodiment of noise prevention,
In this embodiment, during the read operation, only the transistors 320 and 324 of the write amplifier 316 shown in FIG. 35 are turned on and the write pattern is connected to the ground. The read head 15 of the head portion 14-6 which is now located on the lower side
It is assumed that the read operation of -6 is performed. At this time, the write amplifier 316 connects the write patterns 300-6 and 302-6 to the ground. Therefore, the capacitor 32 formed by the three floating capacitors formed with respect to the external noise source 322 is
4, 326, 328, since the write pattern 300-6 side of the first capacitor 324 is grounded by the write amplifier 316, it is not transmitted to the next capacitor 326, and the next write pattern 302-6 is also grounded. Therefore, it is not transmitted to the next capacitor 328.
In this case, the external noise source 322 and the lead pattern 3
04-6 and write pattern 300-6, 302-
Since the two ground patterns pseudo formed in 6 are positioned, it is possible to realize a substantially perfect shield effect for the external noise source 322. That is, FIG.
Noise voltage ΔV from the external noise source 322 shown in (A)
On the other hand, the noise voltage of the write pattern 304-6 is shown in FIG.
As shown in FIG. 9 (B), it becomes constant, and the noise voltage is not superimposed.

Referring again to FIG. 34, in the FPC connection band 62, a bias supply pattern 308 for supplying a bias voltage to the disk via an actuator is formed following the connection pattern for the head.
The head side of this bias supply pattern 308 is screw 27
6 is connected to the actuator side. That is, FIG.
As shown in FIG. 7, by inserting a screw 276 into the through hole 280 formed in the bias supply pattern 308 of the FPC connection band 62 and screwing the screw 276 into the screw hole on the actuator 26 side, the bias supply pattern 308 and the actuator 26 are separated from each other. It is electrically connected. Since the actuator 26 is installed on the base plate 12 as shown in FIG. 2, a bias voltage can be applied to the disks 30-1 to 30-3 of the spindle motor 22 also installed on the base plate 12.

Further, in the FPC connection band 62 of FIG. 34, the connection pattern 3 for the VCM moving coil 90 is used.
10, 312 are provided. This connection pattern 310,
Reference numeral 312 is connected to the drive circuit 320 on the fixed side. Of course, the bias supply pattern 308 is connected to the bias voltage supply circuit 315 on the fixed side. Since the bias voltage supply circuit 318 and the drive circuit 320 are commonly connected on the ground side, only one bias voltage supply pattern 308 is required. 5. Spindle Motor FIG. 40 shows the connection structure of the spindle motor 22 used in the disk device of the present invention to the printed circuit board 340. In the conventional disk device, the spindle motor 22 and the printed circuit board 340 are connected by a connector. Therefore, the number of parts is large, and the device structure is complicated.

In the present invention, the spindle motor 22
A conductive pin 370 having a spring property is provided in the lower part of the same number as the number of the connecting signal lines, and the pin 37 is attached by assembling the spindle motor 22 and the printed circuit board 340 to the base cover.
0 is brought into contact with the connection pattern of the printed circuit board 340 to be electrically connected. The number and arrangement of the pins 370 provided on the lower portion of the spindle motor 22 will be apparent from the bottom view of the base cover 12 shown in FIG. 44, which will be made clear later.

FIG. 41 shows the internal structure of the spindle motor of the present invention in a half section. A fixed shaft 342 is arranged at the center of the spindle motor 22. The fixed shaft 342 is press-fitted and fixed to the motor base 345 arranged in the lower part.
The motor base 345 has a mounting flange 368. A screw hole 344 for screwing and fixing to the cover 10 side is provided on the fixed shaft 342.

A hub 3 made of stainless steel is provided on the outer circumference of the fixed shaft 342 through two sets of bearings 346 and 348 with seals.
50 is rotatably provided. Sealed bearing 34
A magnetic seal is used for 6,348. That is, the magnetic fluid is interposed between the ring-shaped magnet member and the inner fixed shaft 342. In the present invention, a conductive magnetic fluid is used as the magnetic fluid used for the magnetic seal. By using a conductive magnetic fluid for the magnetic seal, the fixed shaft 342 side and the rotating side hub 350 are
Are electrically connected to each other, and the bias voltage supplied to the base plate on which the spindle motor 22 is mounted via the actuator is supplied to each of the disks 30-1, 30-2, and 30-3 mounted on the spindle motor 22. To maintain the disks 30-1, 30-2, 30-3 at the same potential as the head.

Hub 35 of spindle motor 22 of the present invention
As 0, stainless steel, which is a magnetic material, is used, but in the conventional disk device hub, non-magnetic aluminum is used from the viewpoint of cost, and the yoke forming the magnetic circuit is made of magnetic material such as iron. Made separately from the material and assembled to the hub. In the present invention, as the inside of the disk becomes smaller and thinner, the spindle motor 22 is also required to be made smaller, and further, high-speed rotation is required to improve the transfer speed. Therefore, the conventional aluminum hub cannot obtain a starting torque commensurate with the reduction in size and thickness and the increase in rotation speed. Therefore, in the spindle motor 22 of the present invention, the hub 350 is made of an iron-based material such as stainless steel, and since it is a magnetic material, a separate yoke member is not required, and the magnet 354 can be mounted directly.

By using the magnetic material such as stainless steel for the hub 350 in this way, the hub 350 itself has a function as a yoke, and the space for installing the yoke, which has been separately incorporated in the prior art, becomes unnecessary, thereby reducing the internal volume of the motor. Can be big. As a result, the stator core 352 and the rotation-side hub 350 fixedly housed in the motor base 345 are housed.
It is possible to increase the size of the magnet 354 provided in the spindle motor 22 and obtain a sufficient starting torque even if the spindle motor 22 is reduced in size and thickness.

The disks 30-1 to 30-3 are fixed to the outer periphery of the hub 350 of the spindle motor 22. That is,
The disc 30-3 is placed at the bottom, then the next disc 30-2 is placed via the spacer ring 366, and the top disc 30-1 is further placed via the spacer ring 364.
Is put in. A clamp ring 362 is mounted on the top. The clamp ring 362 presses the clamp plate 356 provided inside to the screw hole 360 of the hub 350 with the screw 358 to press the clamp ring 362 and fix the disks 30-1 to 30-3.

In the spindle motor of the present invention, the clamp of the disks 30-1 to 30-3 has a so-called two-piece clamp structure in which the clamp ring 362 and the clamp plate 356 are divided. Conventionally, the clamp ring 362 and the clamp plate 356 are integrated members, and if they are fixed by tightening with the screw 358, the clamp portion on the disk side is warped due to deformation and is not uniform,
There was a possibility that the disc could shift due to aging.

Therefore, according to the present invention, a two-piece type which is divided into a clamp ring 362 and a clamp plate 356.
With the clamp structure, when the clamp plate 356 is pressed with the screw 358, the clamp plate 356
Is not transmitted to the clamp ring 362. Even if the clamp plate 356 is deformed, the clamp ring 362
A vertical force is only applied to. Therefore, the clamp rings 362 make the disks 30-1 to 30-3 uniform.
0-3 can be pressed down.

In the spindle motor 22 of the present invention, the hub 350 is made of stainless steel, but the disks 30-1 to 30-3 fixed to the outer periphery of the hub 350 and the spacer rings 364 and 366 therebetween are made of aluminum material. ing. For this reason, the disk 30-1
.About.30-3 and the spacer rings 364 and 366 have different coefficients of linear expansion.

Therefore, the disks 30-1 to 1-3 stacked on the outer periphery of the hub 350 with the spacer rings 364 and 366 interposed therebetween are provided.
A gap 365 for preventing mutual interference due to the difference in linear expansion coefficient is formed between 30-3. Therefore, even if the linear expansion coefficient is different, the gap 365 exists, so that the disk 3
It is possible to reliably prevent the deviation of 0-1 to 30-3. Further, after the disks 30-1 to 30-3 are assembled to the spindle motor 22, adjustment for maintaining the rotational balance is performed. Conventionally, a balance adjusting weight is fixed to the upper part of the clamp plate 356 with an adhesive. On the other hand, in the present invention, as shown in FIG. 1, in addition to the screw holes at three positions, the clamp plate 352 is provided with the uniform balance adjusting holes 374 at nine positions in addition to the screw holes.

Then, for example, as shown in FIG. 42, a weight 376 for adjustment is fixed by an adhesive in the balance adjustment hole 374 requiring adjustment, and the upper portion thereof is sealed by the seal 37.
Close at 8. This makes it possible to easily and surely set the balance adjustment weight for the clamp plate 352. 6. Base and Cover In the disk device of the present invention, the read head has an MR.
Since the head is used, a bias voltage is applied in order to prevent the destruction of the MR head due to the inflow of a current larger than the read current. As a result, the base and the cover forming the device housing have a potential. Become. Since the disk device of the present invention is incorporated and fixed as an external storage device of another system unit such as a notebook computer, if a potential is applied to the base and the cover, there is a risk of short-circuiting with the incorporated system side unit. is there. Therefore, in the disk device of the present invention, the assembly structure of the system side unit has an insulating structure.

FIG. 43 is an external view of the disk device of the present invention. FIG. 44 shows its plan view and FIG. 45 shows its bottom view. In FIG. 43, the device housing has a two-part structure of a cover 10 and a base plate 12. Base plate 1
Since the second side is attached to the system side unit, mounting blocks 380 and 382 are provided at the bottom of the base plate 12. On the opposite side, mounting blocks 384 and 386 are provided, as is apparent from FIG.

Mounting blocks 380, 382, 384, 3
Each of 86 has an insulating structure in which rubber linings 390, 392, 396, 398 are provided between the base plate 12. Mounting block 380,382,38
Each of 4,386 is composed of an aluminum block,
Mounting screw holes are provided on each of the side surface and the lower surface.

For example, the mounting blocks 380 and 382 are provided with mounting screw holes 388 and 394 on the side surfaces as shown in FIG. Also, mounting blocks 380, 382, 38
As shown in FIG. 45, mounting screws holes 400, 402, 404, and 406 are provided on the lower surfaces of the units 4, 386. Figure 46
Shows the side surface on the right side of FIG. 43, with a part broken away. 47 is an enlarged view of a portion 408 of FIG. As is clear from FIG. 47, for example, a mounting block 380 is attached to the base plate 12 via a rubber lining 390 to insulate the base plate 12. The mounting block 380 is provided with a screw hole 388 from the side and a screw hole 400 from the bottom.
The mounting block body is composed of an aluminum block 412.

FIG. 48 shows the aluminum block 412 of FIG. 47 taken out. Aluminum block 412 has screw holes 388
The main body 414, which has a rectangular shape on the side, is integrally formed with a semi-cylindrical rear part, and mounting pieces 416 open on both sides are provided on the upper part thereof, and the mounting piece 416 is provided with a pair of through holes 418. . Rubber lining 390 is aluminum block 41
Is placed over the top, including the two mounting pieces 416, and
The side surface of the main body 414 is also lined if necessary. The lining may be performed on the block mounting portion on the base plate 12 side, or may be performed on the aluminum block 412 shown in FIG.

FIG. 49 shows another mounting block 420 used in the present invention. This mounting block 420 is made up of the resin body 4
Filling fitting 4 with screw holes 426 and 430 inside 22
24 and 428 are integrally molded. Resin body 42
Since 2 is used, the mounting block 420 itself has an insulating property, and therefore, the rubber lining is unnecessary.

In addition to the insulating structure of the mounting block with respect to the system side unit, the disk device of the present invention has a structure in which the mounting surface of the mounting block slightly projects from the base plate 12. That is, as shown in FIG. 47, each of the side mounting portion and the lower mounting portion of the mounting block 380 projects by ΔS from the side surface and the bottom surface of the base plate 12.

By popping out the mounting block 380,
When attached to the system side unit, a gap of ΔS is always ensured between the system side unit and the base plate 12 to prevent contact with the system side unit and ensure insulation. In addition to this, each of the base plate 12 and the cover 10 is subjected to electrodeposition coating to form an insulating coating.

Further, as shown in FIGS. 43 and 46, the cover 10 is arranged so that the end edge is located inside the end edge of the base plate 12 by ΔS with respect to the base plate 12 attached to the system side unit with an insulating structure. The size is decided. In this way, the base plate 12
On the other hand, by making the outer shape of the cover 10 small, it is possible to reliably prevent a short circuit due to the cover 10 protruding from the base plate 12 and coming into contact with the system unit.

Further, as shown in the enlarged sectional view of FIG.
The cover 10 is fitted into the base plate 12 via the packing 28, and a wall is formed so that the base-side end portion 460 and the cover-side end portion 462 overlap each other at this fitting portion. Due to the overlapping wall structure at the fitting portion of the cover 10 and the base plate 12,
Even if the packing 28 is provided, no gap is generated between them, and a shield structure that surely prevents external noise from entering the inside is realized.

Further, according to the present invention, in the assembled state shown in FIG. 2, the space below the base plate 12 forms the circuit accommodating portion 410. This circuit housing portion 410 has a structure shown in FIG.
The printed circuit board on which the drive controller 1012 shown in FIG. A DIP switch for setting parameters unique to the disk device is mounted on a printed circuit board incorporated in the circuit housing portion 410 below the base plate 12.

Normally, since the dip switch is mounted on the printed board, the circuit unit becomes thicker by the amount of the dip switch provided. Therefore, in the disk device of the present invention, as shown in FIG. 50, a dip switch having a structure embedded in a printed circuit board is mounted so that the circuit unit can be made thin. In FIG. 50, the printed circuit board 340 is incorporated in the circuit housing portion 410 on the back side of the base plate 12. A dip switch 432 having a structure in which a switch knob is provided on the back surface side of the printed circuit board 340 is incorporated in a notch 436. FIG. 51 shows the built-in portion of the DIP switch 432 of the printed circuit board 340 taken out. The lower surface side of the printed board 340 is a component mounting surface in the illustrated state, a circuit pattern is formed on the component mounting surface, and the components 444 and 446 are surface-mounted on this circuit pattern. A cutout 436 is provided at the mounting position of the DIP switch 432.

The DIP switch 432 has lead terminals 440 and 442 drawn out from the side surface, and other parts 44
It can be surface-mounted like 4,446. A surface of the lead terminals 440 and 442 of the dip switch 432, which is located on the opposite upper side in the surface mounting state, becomes a switch surface 438. As shown in FIG. 50, the switch surface 438 is provided with, for example, eight slide grooves, and switch knobs 434-1 to 434-8 are provided in the slide grooves. The internal switch structure itself is the same as the conventional dip switch. The switch surface 438 is a switch knob 434-1 to 43-4.
It is desirable to indent 34-4 in order to make it slightly pop out.

With such a mounting structure of the DIP switch 432, the height of the DIP switch 432 can be reduced by the thickness of the printed board 340, and as a result, the circuit unit mounted on the printed board 340 can be thinned. Also, the switch knob 4 of the DIP switch 432.
Since 34-1 to 434-8 are open to the bottom side, the setting operation of the DIP switch, which is performed at the time of factory shipment or adjustment, can be performed very easily.

Although the above embodiment has been described by taking a disk device using a 2.5 inch size disk medium as an example, the present invention is not limited to this and a disk medium of an appropriate size is used. It can be applied as is to the compact disc device. Further, the present invention is not limited by the numerical values shown in the embodiments.

[0143]

As described above, according to the present invention, the following effects can be obtained. First, in an asymmetric actuator, by arranging the center of gravity on the coil side on the straight line connecting the center of gravity on the head side with respect to the center of rotation, a good balance in the front-back and left-right directions can be obtained, and external vibration and Positioning with an actuator that is highly stable against impact can be realized.

Since the attraction force of the magnet is used for assembling the yoke on the fixed side of the VCM, the number of assembling steps can be reduced and the assembling accuracy can be improved with a small number of parts. Further, the rotation torque of the VCM can be increased by widening the front and rear widths of the magnet so as to maximize the effective coil length.

Further, the FPC connection band for electrically connecting the fixed side circuit portion and the movable side actuator can be easily positioned and fixed by the one-touch assembly of the band pressing member having the spring property, and the band corresponding to the movement of the actuator. It is possible to stabilize the curved deformation of the actuator and prevent contact with other components and application of an abnormal external force to the actuator.

By providing a pattern in the FPC connection band for supplying the bias voltage required for using the MR head for reading, the bias potential can be easily applied to the disk medium without the need for a dedicated line. Can be supplied. Furthermore, regarding the arrangement of connection patterns for the write head and the read head in the FPC connection band,
By arranging so that the write pattern is located on the outermost side, the write pattern located on the outer side during the read operation is set as a pseudo ground pattern, thereby suppressing the superposition of external noise on the read pattern, and It is possible to improve the S / N ratio.

Further, since the MR head is used as the read head, the disk cover and the case have a potential. However, by providing the system side unit with an insulating structure, the system side unit has the disk structure. The risk of short circuit when the device is attached can be reliably prevented.
From the above, it is possible to reduce the size of the disk device while maintaining high quality.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an internal structure of a disk device of the present invention.

FIG. 2 is a sectional view taken along the line II of FIG.

FIG. 3 is an exploded view of the disk device of the present invention.

FIG. 4 is a circuit block diagram of a disk device of the present invention.

FIG. 5 is an explanatory diagram of balance adjustment in the actuator of the present invention.

FIG. 6 is an explanatory view of a balance adjustment actuator not according to the present invention.

FIG. 7 is a sectional view showing a rotation axis of the actuator.

8 is a sectional view taken along line II-II of FIG.

FIG. 9 is an explanatory diagram showing manufacturing of an actuator block by drawing.

FIG. 10 is an exploded view of the fixed side of the VCM.

FIG. 11 is an explanatory diagram of an assembled state of the VCM fixed side.

FIG. 12 is an explanatory diagram of a lower yoke including a lower magnet.

FIG. 13 is an explanatory diagram of an upper yoke including an upper magnet.

FIG. 14 is an explanatory diagram showing a relationship between a magnet and a movable coil.

FIG. 15 is an explanatory view showing an overlap in the front-rear direction of the magnet with respect to the movable coil.

FIG. 16 is an explanatory diagram of the action due to the overlapping of magnets.

FIG. 17 is a characteristic graph diagram showing the relationship between the thrust force of the rotational force and the overlap.

FIG. 18 is a sectional view of an integrated structure of a VCM and an actuator.

FIG. 19 is an explanatory diagram of a stopper mechanism of an actuator.

20 is an explanatory view of the latch plate of FIG.

FIG. 21 is an explanatory view showing a latch function by a magnet attractive force.

22 is a sectional view of the stopper portion of FIG. 22.

23 is a sectional view taken along line III-III in FIG.

24 is an explanatory view of the holder of FIG. 22.

FIG. 25 is an explanatory view showing a collision state of the inner stopper.

FIG. 26 is an explanatory view showing a collision state of the outer stopper.

FIG. 27 is an explanatory view of a connecting portion between the FPC circuit board and the actuator.

FIG. 28 is an exploded view of the FPC circuit board side.

29 is an explanatory view of the substrate plate of FIG. 28.

FIG. 30 is an explanatory view showing the mounting of the band pressing member to the assembly of the FPC circuit board.

FIG. 31 is an explanatory view showing a plane and a side surface of the band pressing member.

FIG. 32 is an explanatory view showing the band pressing member in a stereoscopic view.

FIG. 33 is an explanatory view of the FPC board when the band pressing member is attached.

FIG. 34 is an explanatory diagram of a circuit pattern of an FPC connection band.

35 is a circuit diagram of the write amplifier of FIG. 34.

FIG. 36 is an explanatory diagram of a noise prevention function by opening a light pattern.

37 is an explanatory diagram of the external noise voltage and the read pattern noise voltage of FIG. 36.

FIG. 38 is an explanatory diagram of a noise prevention function by grounding a light pattern.

FIG. 39 is an explanatory diagram of the external noise voltage and the read pattern noise voltage of FIG. 38.

FIG. 40 is an explanatory view showing a printed circuit board connection structure of a spindle motor.

FIG. 41 is an explanatory cross-sectional view of a spindle motor

FIG. 42 is an explanatory diagram showing balance adjustment of the spindle motor.

FIG. 43 is a front view of the disk device.

FIG. 44 is a plan view of the disc device.

FIG. 45 is a bottom view of the disc device.

FIG. 46 is a rear view of the disc device.

47 is a partially enlarged view of FIG. 46.

48 is an explanatory diagram of the connection block of FIG. 46.

FIG. 49 is a sectional view showing another embodiment of the connection block.

FIG. 50 is an explanatory diagram of circuit mounting by embedding dip switches.

51 is a sectional view of the printed circuit board shown in FIG. 50.

[Explanation of symbols]

10: cover 12: base plate 14-1 to 14-6: head part 15-1 to 15-6: read head (MR head) 16, 16-1 to 16-6: write head 18: head IC circuit 20: voice Coil motor (VCM) 22: Spindle motor 24: Lower yoke (bottom plate) 26: Actuator 28: Packing 55: Circulation filter 60: FPC board 62: FPC connection band 80-1 to 80-4: Arm part 82-1 to 82-6: Gimbal spring 86: Rotating shaft 88: Coil supporting plate 90: Moving coil 92: Center of rotation 94: Head center 98: Head side center of gravity position 100: Coil side center position 104: Fixed shaft 106, 108: Groove 110: Shaft Part 112: Screw hole 114, 116: Ball bearing 118, 120: Aeta Race 130: Spring 132, 134: Seal plate 136: Extruded mold material 142: Arm block 152: Upper yoke 154: Lower magnet 156: Upper magnet 166: Protrusion 168: Receiving hole 174, 176, 178: Standing piece 178, 184, 186 , 188: magnet outer end 180, 182: coil inner end 196: stopper part (inner side) 198: latch magnet 200: latch piece 202: latch plate 203: stopper step part 204: holder 206-1, 206-2: rotation Stop portion 208: Hard rubber layer 210: Soft rubber protrusion 224, 232: Collision surface 218: Stopper portion (outer side) 240: Substrate plate 242: Double-sided adhesive sheet 244: Band support portion 246: Fitting hole 248: J-shaped receiver Part 254: Notch 260: Band pressing member 262, 264: spring plate part 265: band drawing part (connection pattern part) 266, 268, 270: positioning piece 267: protrusion 272: inverted J-shaped pressing part 276: screw 180: screw hole 300-1,300 -6, 302-1, 302-6: Write pattern 304-1, 304-6, 406-1, 306-6: Read pattern 308: Bias supply pattern 314: Select circuit 315: Bias voltage generation circuit 316: Write amplifier 320: VCM drive circuit 318, 120, 322, 324: Transistor 322: External noise source 324, 326, 328: Capacitor 340: Printed circuit board 342: Fixed shaft 344: Screw hole 345: Motor base 346, 348: Sealed bearing 350 : Hub (stainless steel) 352 Stator core 354: Magnet 356: Clamp plate 364, 366: Spacer ring 368: Flange 380, 382, 384, 386: Mounting block 390, 392, 396, 398: Rubber lining 410: Circuit housing 412: Aluminum block 432: DIP switch 436: Notch 434-1 to 434-8: Switch knob 438: Switch surface

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] February 2, 1995

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Fig. 29

[Correction method] Change

[Correction content]

FIG. 29

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Name of item to be corrected] Fig. 30

[Correction method] Change

[Correction content]

FIG. 30

[Procedure 3]

[Document name to be corrected] Drawing

[Correction target item name] Fig. 31

[Correction method] Change

[Correction content]

FIG. 31 ─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] May 11, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0059

[Correction method] Change

[Correction content]

More specifically, first, the weight on the head side provided with the arm 80-1 and the gimbal spring 82-2 is determined, and the through hole 87-1 and the through hole 87-2 are provided for the weight on the head side. Set the weight on the coil side so that the weight is the same. Then, the head-side center of gravity position 98 and the coil-side center of gravity position 100 may be obtained and arranged so as to be aligned on a straight line 102 passing through the rotation center 92. in this way
The conventional actuator 26 shown in FIG.
Head center 94 of core, center of rotation 92, and coil 90
The shape center 96 of the
Balun if necessary so that the center of gravity comes to the center of rotation 92.
Assemble actuators by attaching or scraping weights
I was balancing at the beginning. Therefore, FP
If parts such as C are attached later, the balance will be lost.
I put a weight on it for a better balance
It was Therefore, the inertia of the actuator becomes large.
Was there. On the other hand, the actuator 26 of the present invention shown in FIG.
Is the center of rotation when parts such as FPC are attached later.
The center of gravity of the coil 100 and the center of rotation 9 so that the center of gravity comes to 2
2 and the center of gravity 98 on the head side form a straight line 102
It is configured as Therefore, assemble the actuator
At this time, it is not necessary to use a weight for balance adjustment,
Quantification is possible and high-speed access is possible. I like this
The access time is reduced to the conventional level by reducing the inertia and weight.
We were able to reduce it from 15ms to 12ms.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kenshi Endo, Higashine, Higashine, Yamagata Prefecture 5400-2 Omori, Higashinemoto, Higashine, Tone, Yamane (Fujitsu Limited) (72) Inventor, Katsu Saiki, Nakahara, Kawasaki, Kanagawa 1015 Odanaka, Fujitsu Limited (72) Inventor Tsutomu Sasaki, Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture 1015, Fujitsu Limited (72) Inventor, Koichi Ishizaki, 1015, Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture, Fujitsu Limited ( 72) Inventor Takahiro Ono 1015 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture, Fujitsu Limited

Claims (21)

[Claims] 1. A disk medium (30) rotated by a spindle motor (22), and the disk medium (30).
An actuator (26) for movably supporting the head (14) in the radial direction with respect to the recording surface of the disk, and a voice coil motor (20) for rotating the actuator (26) within a predetermined rotation angle range. In the disk device, the actuator (26) has a head (14) at the tip.
The voice coil motor, which is integrally formed on the rear portion of the shaft mounting portion (85) and the shaft mounting portion (85) integrally formed at the base of the arm portion (80). The movable coil (90) of (20) is supported by the coil supporting portion (88), and the actuator (2
6) Rotation center (92) and head side center of gravity (98)
The position of the center of gravity on the coil side (1
00) are arranged so that the arm portion (80), the shaft mounting portion (85), and the coil supporting portion (88) are arranged so that 00) are arranged side by side. 2. The disk device according to claim 1, wherein the arm portion (80) of the actuator (26) has an asymmetrical shape in which the tip end side on which the head (14) is mounted is bent in the disk center direction. A disk device characterized by being present. 3. A disk medium (30) rotated by a spindle motor (22), and the disk medium (30).
An actuator (26) for movably supporting the head (14) in the radial direction with respect to the recording surface of the disk, and a voice coil motor (20) for rotating the actuator (26) within a predetermined rotation angle range. In the disk device, the voice coil motor (20) has a flat movable coil (90) supported on the actuator (26) side.
And a pair of permanent magnets (154, 156) fixedly arranged at positions sandwiching the movable coil (90), and a pair of yoke members (24) supporting the permanent magnets (154, 156) to form a magnetic circuit. , 152), and the pair of yoke members (24, 152) are connected to the permanent magnets (154, 1).
56) and fixed by combination by adsorption by the movable coil (9).
0) A disk device having a combination structure for forming a storage space of 0). 4. The disk device according to claim 3, wherein the pair of yoke members (24, 152) are flat plate members, and the pair of permanent magnets (154, 156) are provided on the one plate member. A plurality of upright pieces (174, 176, 178) for determining the coil accommodation interval between them are provided, and at least one upright piece (176) is provided with a positioning projection (166) at the tip thereof, and further said projection (166).
A disk device, wherein a positioning receiving hole (168) is formed at a position of the other plate member opposite to the above. 5. A disk device according to claim 3, wherein said pair of pairs of said front and rear inner ends (178, 182) of said movable coil (90) in the arm radial direction of said actuator (26) are provided. The outer ends (178, 184, 186, 188) of the front and rear of the permanent magnets (154, 156) are arranged so as to slightly overlap with each other, and the torque generation effective portions formed by the left and right coil portions of the movable coil (90) are exceeded. A disk device, wherein the magnetic flux of the permanent magnets (154, 156) is passed therethrough. 6. A disk medium (30) rotated by a spindle motor (22), and the disk medium (30).
An actuator (26) for movably supporting the head (14) in the radial direction with respect to the recording surface of the recording medium, a voice coil motor (20) for rotating the actuator (26) within a predetermined rotation angle range, A disk device comprising a head (14) mounted on an actuator (26) and a connection band (62) integrally drawn from the circuit board (60) for connecting an FPC circuit board (60) fixedly arranged. The band lead-out portion (265), which is erected from the circuit board (60) and integrally draws out the connection band (62) from one of the erected side ends via a U-shaped bent portion, and the band lead-out portion (265). A plate member (240) having a band support portion (244) provided with a J-shaped receiving portion (248) standing upright so as to fix 265) and a leaf spring portion (262). Conversely J-shaped pressing portion which (27
2), and a band pressing member (260) for pressing and holding in the J-shaped receiving portion (248) of the band supporting portion (248) to sandwich and hold the U-shaped bent portion of the band withdrawing portion,
A disk device comprising: 7. The disk device according to claim 6, wherein the band pressing member (260) has the inverted J-shaped pressing member formed at one end and is engaged with the other end of the band supporting portion at the other end. A disk device comprising a leaf spring part that is folded in two and is formed with a bent part. 8. The disk device according to claim 7, wherein the band pressing member (260) has a fitting hole (2) formed in the band supporting part (244) at the tip of the bent part.
46) A disk device, characterized in that it is provided with a protrusion (274) which is fitted to the (46). 9. A disk device according to claim 6 or 7, wherein said band pressing member (260) is provided with said band supporting part at the side end of said plate spring part (262) for band pressing folded in two. Positioning pieces (266, 268, 27) for positioning the connection band (62) in the band width direction with respect to (244).
0) is formed. 10. A plurality of head units comprising a disk medium (30) rotated by a spindle motor (22), a write head (16) for writing to the disk medium and a read head (15) for reading. (14), an actuator (26) for movably supporting a plurality of heads (14) in the radial direction with respect to the recording surface of the disk medium (30), and an actuator (26) having a predetermined rotation angle. Voice coil motor (20) that rotates in a range
And a connection band (62) formed of an FPC for connecting between a plurality of heads (14) mounted on the actuator (26) and a fixedly arranged circuit board (60). The connection band (62) has the plurality of head portions (14).
Of the read head (15) and the write head (16), and the connection pattern is arranged so that the connection pattern for the write head (16) is located on the outermost side in any one of them. Disk device characterized by. 11. The disk device according to claim 10, wherein when a read operation is performed on any one of the head portions (14), it is electrically connected to a connection pattern located on the outermost side of the write head (16). A disk device comprising circuit means for opening. 12. The disk device according to claim 10, wherein when a read operation is performed on any one of the head portions (14), the write head (16) is electrically connected to an outermost connection pattern. A disk device comprising circuit means for connecting to a ground. 13. A disk medium (3) comprising a read head (15) containing a magnetoresistive element, the disk medium (3) being housed in a housing having a base (12) and a cover (10) at least divided into two parts.
0) at the time of reading, at least the read head (15)
A disk device for applying a specified bias voltage to each of the disk medium (30), characterized in that the specified bias voltage is applied to the housing by a fixing member that fixes the circuit board. 14. The disk device according to claim 13, wherein an insulating structure is provided on a mounting surface of the housing to another unit. 15. The disk device according to claim 14, wherein an insulating layer formed by forming a rubber lining or an insulating film is formed as the insulating structure. 16. A disk drive according to claim 14, wherein the insulating structure is provided with a connection block member insulated from the housing side, and the mounting block member is slightly projecting from the housing surface. A disk device having a surface. 17. The disk device according to claim 16, wherein the mounting block member is formed by rubber lining a metal block having a mounting screw hole. 18. The disk device according to claim 16, wherein the mounting block member is a resin block having mounting screw holes. 19. The disk device according to claim 14, further comprising an FPC for connecting between the head portion (14) mounted on the actuator (26) and a fixedly arranged circuit board (60). And a bias supply pattern (308) for applying the bias voltage is formed in addition to the connection pattern for the head portion (14) formed in the connection band (62). Disk device. 20. The disk device according to claim 14, wherein the bias supply pattern (308) is electrically connected to a screw member for fixing the connection band (62) to the actuator (26), and the actuator (26). Device for supplying a bias voltage to 21. A base (12) and a cover (10) having a casing having at least a two-part structure, said cover (1)
0) is fitted into the base (12) in an overlapped manner, and packing is interposed in the fitted portion.