JP2956813B2 - Magnetic disk drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk drive, and more particularly to an improvement in a head positioning mechanism.

[0002]

2. Description of the Related Art As one type of magnetic disk device used as an external storage device such as an electronic computer, a disk as a magnetic storage medium is rotated and a head is moved on the disk so that the head can arbitrarily change the surface of the disk. There is known a device in which information is written or read at the position of (1).

This magnetic disk device has a structure as shown in FIG. 8, for example. FIG. 8 shows a magnetic disk drive of the type in which the head is positioned by moving the head in the radial direction of the rotating disk by causing the carriage to perform a linear motion.

[0004] A disk a is fitted and fixed to a spindle b. The spindle b is held by a spindle bearing d in a housing c. The spindle motor e is installed in the housing, and coupling the shaft to the spindle. The head f is attached to the guide arm g via a gimbal. The guide arm g is installed on the carriage h. The carriage h moves the head in the radial direction of the disk by rolling the rollers on the rail on the housing.

Driving is performed by an actuator having a coil i and a magnet. The coil i is attached to the carriage h, and the magnet is fixed to the housing together with the yoke j that carries the magnet. The electromagnetic movement between the coil and the magnet causes the carriage to make the linear movement.

In such a magnetic disk drive, the carriage h moves by the electromagnetic action of the coil and the magnet.
At this time, the magnet and the yoke j carrying the magnet are receiving a reaction force. Since the yoke j is directly fixed to the housing c, the reaction force is directly transmitted to the housing c, and further transmitted to the spindle b via the spindle bearing d. Since the spindle bearing d has a relatively low rigidity, a spring-mass system is configured in which the spindle bearing d is a spring and the spindle b is a mass, and the spindle b vibrates together with the disk a. Since the spindle bearing has almost no viscosity, the vibration peak at the resonance frequency is high, and the carriage cannot sufficiently follow this vibration, and a positioning error of the head occurs. In the following description, such vibration will be referred to as spindle vibration.

FIG. 9 shows the relationship between spindle vibration and head positioning accuracy. The horizontal axis represents the frequency, and the vertical axis represents the displacement of the head, that is, the positioning error of the head. In the above-described magnetic disk drive, when the excitation frequency component in the reaction force against the member on the housing side of the actuator matches the natural frequency of the spindle, the viscosity of the spindle bearing is small. And the positioning accuracy of the head decreases.

In order to prevent spindle vibration and improve head positioning accuracy, see, for example, Japanese Patent Application Laid-Open No. 64-396.
In Japanese Patent Publication No. 85, a magnetic circuit composed of a magnet and a yoke on the housing side of an actuator is supported by a leaf spring and a shear rubber damper, and as shown by reference numeral B in FIG. By lowering the frequency, the spindle vibration is reduced.

Further, US Pat. No. 3,643,242 is disclosed.
No. In both when you move the member is in the housing side of the actuator in the same direction as the seek direction of the head,
The housing-side member is connected to a diaphragm in the housing, and the movement of the housing-side member is regulated by the diaphragm to reduce spindle vibration.

[0010]

Problems to be Solved by the Invention
In the magnetic disk drive disclosed in Japanese Patent Application Laid-Open No. 5 (1999) -1990, even if the supporting natural frequency of the magnetic circuit is made lower than the natural frequency of the spindle and the vibration is attenuated by the shear rubber damper, as shown by reference numeral B in FIG. Since the natural frequency is higher than the supporting natural frequency of the magnetic circuit, the spindle and the housing integrally vibrate as a leaf spring between the magnetic circuit and the carriage, and the carriage does not follow the spring. There is a limit to improving accuracy.

Of course, as indicated by reference numeral C in FIG. 9, the housing-side member of the actuator, that is, the supporting natural frequency of the magnetic circuit is made sufficiently low, and the high compression in the low frequency range of several tens Hz or less in the servo system. The positioning accuracy of the head can be improved by making the carriage follow the movement of the spindle and the housing by utilizing the characteristics.However, since the amplitude of the leaf spring cannot be increased, the natural frequency of the housing-side member of the actuator is reduced to that level. It cannot be lowered, and the positioning accuracy of the head can not be improved.

In the magnetic disk drive disclosed in US Pat. No. 3,643,242, the member on the housing side of the actuator, that is, the magnetic circuit is supported by linear bearings. In comparison, the amplitude at a low frequency can be increased.

[0013] However, the diaphragm, since the attenuation characteristic is not good, the reaction force to provoked a resonance when applied to the housing side member of the actuator, the amplitude of the housing side member is also several times the normal amplitude. If the amplitude becomes excessive, the diaphragm deforms in an unscheduled direction, the spring constant sharply increases, the natural frequency of support of the magnetic circuit increases, and the acceleration of vibration transmitted to the housing changes suddenly. Positioning accuracy is reduced.

An object of the present invention is to provide an improved magnetic disk drive capable of eliminating the influence of the positioning accuracy of the head due to the vibration of the member on the housing side of the actuator based on the reaction force generated at the time of head seeking. It is in.

[0015]

In order to achieve the above object, the present invention provides a head assembly including a disk, a drive mechanism for supporting and rotating the disk, and a head for writing and reading information to and from the disk. A mechanism that supports the head assembly, a mechanism that guides the support mechanism so that the head moves on the disk, a housing that carries these mechanisms, a coil and a magnet, and one of these is a support mechanism. An actuator carried on the other side by the housing, a guide mechanism for causing the support mechanism to move in the same direction as the moving direction of the support mechanism on a member on the housing side, and when the actuator causes the head to make the movement. On the housing side of the actuator due to the reaction force generated Characterized by comprising an air spring having an aperture for attenuating vibration generated in wood.

Another feature of the present invention is that a member on the supporting mechanism side of the actuator is provided with a spring between the housing and the member for regulating a relative positional relationship with members around the supporting mechanism.

[0017]

When an electric current is applied to the coil of the actuator, a mechanism for supporting the head assembly, such as a carriage and a swing arm, linearly moves or swings by the electromagnetic action of the coil and the magnet, and does not perform the movement required for positioning the head. Let it. When the actuator operates, the member on the housing side of the actuator receives a reaction force, but the guide mechanism releases the reaction force, and the reaction force is not transmitted to the spindle via the housing, so that spindle vibration does not occur, The positioning accuracy of the head is improved.

Further, in the magnetic disk drive of the present invention,
By the guide mechanism and the air spring with the throttle, the supporting natural frequency of the member on the housing side of the actuator can be designed to be low, and the state of reference numeral c in FIG. 8 can be realized.
High positioning accuracy can be obtained.

Further, even if a reaction force that causes resonance of the housing side member of the actuator is generated, the amplitude is reduced because the large damping force is obtained by the throttle of the air spring, and the amplitude is reduced by the amplitude of the coil or magnet. , The clearance between the coil or the magnetic circuit and other components can be designed to be small, and cost reduction and miniaturization of the HDA can be realized.

In addition, a spring disposed between the housing-side member of the actuator and the housing constantly regulates the relative positional relationship between the housing-side member of the actuator and peripheral members within the movable range of the member. So
Even if the HDA is tilted, the impact based on the interference of these members is not generated, and together with the fact that it is not affected by the vibration based on the reaction force generated by the head seek described above, the positioning of the head can be performed with extremely high accuracy. You can do it.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the magnetic disk drive according to the present invention will be described below in detail with reference to the drawings.

FIGS. 1 and 2 show a magnetic disk drive of the type in which the head moves linearly in the radial direction of the disk.

The housing 11 is mounted on an apparatus frame 14 via a rubber cushion 13. The housing itself consists of two parts, which are fastened by bolts. Inside the housing, a disk, a drive mechanism that supports and rotates the disk, a head assembly that includes a head that performs information writing and reading operations on the disk, a carriage that supports the head assembly, and movement of the disk on the head A mechanism for guiding the carriage so as to perform the operation is accommodated.

The disk 15 is fitted on a spindle 16,
And fixed. The spindle 16 is the housing 11
Is held by a spindle bearing 17. The spindle motor 18 is mounted on the housing 11 and has its shaft connected to the spindle 16. Head 1
9 is attached to the end of the guide arm 20 via a gimbal. The guide arm 20 is installed on the carriage 21. The carriage 21 is configured to linearly move the head 19 in the radial direction of the disk 15 by the rollers 22 attached to the carriage 21 rolling on rails 23 supported by the housing 11. Driving is performed by an actuator. The actuator linearly moves the carriage 21 by the electromagnetic action of the coil 24 and the magnet.
Is incorporated in the carriage 21 and the magnet is the yoke 2
6 attached.

In the magnetic disk drive, a guide mechanism for causing the yoke 26 carrying the magnet to move in the same direction as the moving direction of the carriage 21 and a reaction force generated when the actuator moves the carriage 21 are used. An air spring 30 having a throttle that attenuates vibration generated in the yoke 26, a spring 3 that regulates a relative positional relationship between the yoke 26 and the carriage 21 within the movable range of the yoke 26 and peripheral members such as the coil 24 on the carriage.
It is equipped with a 2.

FIGS. 3 and 4 show more specifically the configuration of the guide mechanism and the air damper with a throttle compared to the schematic configuration diagrams shown in FIGS. 1 and 2. FIG.

The housing 11 is, as shown in FIG.
It is composed of two parts, a spindle part on which a disk or the like is mounted and an actuator part, and is connected by bolts. The housing on the side of the actuator section has a mouth shape. The rail 23 is supported by the housing 11 at both ends.

The yoke 26 is incorporated in the housing 11 with a linear bearing 31 interposed . Linear bearings 31, as shown in FIGS. 3 and 4, are arranged in plane direction of the disk 15 of the yoke 26 to reduce the thickness or height of the housing 11 is a lamination direction of the disc 15. The case for holding the needle roller and the ball on one of the linear bearings 31 is the housing 11.
, But the other is fixed to a leaf spring 35.

The leaf spring 35 is disposed so as to cover the opening 33 on the side surface of the housing 11, and has both ends of the housing 1.
1 is fixed by bolts. The leaf springs 35 play a role in preventing the generation of excessive thermal stress on the balls and the raceway surfaces of the linear bearing due to the difference in the coefficient of linear expansion or the difference in the temperature distribution due to the difference in the material. A stopper 36 made of rubber or the like is attached to the yoke 26 at each of the moving ends of the yoke 26.

The air spring 30 includes a hollow member flexible, the movable member you coupled to the stationary member and arranged on the opposite side and the yoke 26 is disposed on one side of the hollow member in order to identify the deformation direction of the hollow member Have. Of these, the hollow member is indicated by reference numeral 37,
It is formed of a thin, rubber-shaped molded product of a thin cylindrical shape having a curved peripheral surface and open ends. The movable member includes a back plate 42 and a stop member 38, and the hollow member 37 is fixed to the back plate 42 by the stop member 38. The stop member 38 has a disc shape, is disposed inside the opening of the hollow member 37 so as to contact the inner surface of the wall forming the outer opening of the hollow member 37, and is fixed to the back plate 42 by bolts. ing. The stationary member comprises a substrate 43 having a through hole including a stop 40 at the center and a ring 44. The substrate 43 is arranged inside the hollow member 37 so as to contact the outer surface of the wall forming the opening facing the yoke 26 in the hollow member 37, and the ring 44 is formed on the inner surface of the wall forming the opening facing the yoke 26. To the substrate 43 by bolts.
Has been concluded. The back plate 42 is attached to the yoke 26 with the rod 41
Are joined by

The spring 32 comprises a magnet 25 and a yoke 26
The gap between the magnetic circuit constituted by the above and the housing 11 is maintained evenly even when the HDA is inclined, to maintain the relative position between the coil 24 and the magnet 25, and to prevent the thrust of the carriage from dropping. The movable member is disposed between the back plate 42 and the substrate 43. HDA does not tilt,
The spring 32 is unnecessary when the magnetic disk device is held horizontally. However, when the magnetic disk device is installed at an angle due to the inclination of the installation floor, considering the creep of the rubber of the hollow member, in order to keep the clearance uniform. Spring 32 is required.

In this magnetic disk drive, the head 1
The positioning of 9 is performed by operating the spindle motor 18, rotating the disk 15 together with the spindle 16, passing a current through the coil 24 of the actuator, moving the carriage 21, and controlling the current flowing through the coil 24. You. When head seek is performed, the yoke 26 is subject order to move the electromagnetic action of the coil 24 and the magnet 25, the reaction force.

In the conventional apparatus, this reaction force is transmitted directly to the housing because the magnet or coil is directly carried on the housing, and further passes through a spindle bearing constituting a drive mechanism for rotating the disk. It has been transmitted to the spindle Te. Since the spindle bearing has relatively low rigidity, a spring-mass system is formed, in which the spindle bearing is a spring and the spindle is a mass, and not only does the spindle resonate with the disk, but the spindle bearing has almost no viscosity. The resonance peak is quite high
Was .

However, in the magnetic disk drive according to the present embodiment, since the linear bearing does not transmit the reaction force generated by the head seek to the spindle, no vibration is generated in the spindle, so that the positioning accuracy is improved.

Even if a reaction force causing resonance of the magnetic circuit composed of the magnet 25 and the yoke 26 is generated by the head seek, since the damping force of the air spring 30 is largely obtained by the throttle 40, The magnification and the amplitude are small, an extra dimension increase with respect to the amplitude of the magnet, the clearance between the magnetic circuit and other parts can be designed to be small, and cost reduction and miniaturization of the HDA can be realized.

Further, a leaf spring 35 disposed between the back plate 42 and the substrate 43
To prevent the interference between the yoke and other parts, and there is no shock generated by the interference, so that the head positioning is not affected by the reaction force generated by the head seek. It can be performed with extremely high accuracy.

In the magnetic disk drive of the present embodiment,
Since the yoke 26 is supported by the housing 11 with the linear bearing 31 interposed therebetween and the yoke 26 can be moved with low friction, only the component force due to the friction of the reaction force generated by the head seek received by the magnetic circuit passes through the housing 11. Since the vibration is not transmitted to the spindle 16, the phenomenon of vibrating the spindle can be minimized.

Further, since the linear bearings 31 are symmetrically positioned on both sides of the yoke 26, the vibration modes are symmetrical, and the influence on the positioning accuracy of the head is reduced.
Because it is arranged in a direction perpendicular to the surface of the disk 15 or the spindle 16 where there is room for space,
An increase in the size of the magnetic disk drive can be minimized.

The flexible hollow member 37 forming the air spring 30 is prevented from being deformed in the lateral direction by the stationary member and the movable member that moves together with the magnetic circuit by the linear bearing, that is, the horizontal member is not deformed. Since the deformation in the direction is prevented without any special member, the structure of the air spring 30 is simplified, the air spring 30 can be made compact, and the distortion due to the deformation is small, so that the reliability is high. And the life is long.

The hollow member 37 is made of fluorine rubber, which generates very little gas, and the attenuation is performed by using the air inside the housing. Do not pollute.

Further, the spring 32 maintains the relative initial positions of the magnet 25 and the coil 24, and the magnetic circuit and the housing, and the HDA supported by the vibration-proof rubber is installed in an inclined state, or the entire magnetic disk device is mounted. Even if the magnets are inclined, it is possible to prevent a decrease in thrust due to a relative displacement between the magnet 25 and the coil 24, and to prevent a decrease in head positioning accuracy due to an impact generated by interference between the magnetic circuit and the housing.

The leaf spring 35 not only prevents an increase in stress or frictional resistance of the linear bearing 31 due to a difference in thermal expansion coefficient or temperature distribution between the housing 11 and the yoke 26, but also causes an assembly error. However, since this can be absorbed and the linear bearing 31 can be brought into contact with the yoke 26, mounting can be performed very easily.

The arrangement of the linear motors shown in FIGS. 3 and 4 can be applied not only to the carriage mechanism of the magnetic disk drive but also to a device for moving any non-moving object using a linear actuator. in this case,
What is necessary is just to fix the non-moving object to the moving part to which the coil or the magnet is fixed, and fix the member to which the magnet or the coil is fixed to the base member via the linear bearing and the damping mechanism (air damper with throttle).

FIG. 5 shows another embodiment of the present invention, and shows another example of the structure of a magnetic disk drive of the type in which the head makes a linear motion in the radial direction of the disk.

The housing 111 is mounted on the device frame 114 via the vibration-proof rubber 113. The housing itself consists of two parts, which are fastened by bolts. Inside the housing, a disk, a drive mechanism for supporting and rotating the disk, a head assembly including a head for writing and reading information to and from the disk, a carriage for supporting the head assembly, and moving the disk on the head A mechanism for guiding the carriage so as to perform the operation is accommodated.

The disk 115 is fitted and fixed to a spindle 116, and the spindle is held by a spindle bearing 117 in a housing 111. The spindle motor 118 is mounted on the housing 111 and has a shaft connected to the spindle 116. The head 119 is attached to the guide arm 120 via a gimbal, and the guide arm is installed on the carriage 121. The carriage 121, the roller 122 in this by rolling on rails 123 supported on housing 111, it moves the head 119 in the radial direction of the disk 115. The movement of the carriage is performed by an actuator. The actuator intended to made to move in the carriage by electromagnetic action between the coil and the magnet, the coil 124 to the carriage 121, and only each with up to a magnet housing 111.

In the magnetic disk drive of this embodiment,
Yoke 126 carrying the magnet is interposed a guide mechanism such as a small linear bearings 131 of movable frictional resistance in the same direction as the carriage 121 that is attached to the housing 111 in the actuator. The yoke 126 is arranged so that vibration is attenuated by an air spring 130 arranged between the yoke 126 and the housing 111 .
The magnet is disposed between the housing 111 and the magnet.
The coil 121 is disposed so as not to interfere with the carriage 121, the coil 124 on the carriage, and the like.

The air spring 130 includes a flexible hollow member 137, a stationary member constituted by a housing end wall located on one side of the hollow member, and a movable member 138 disposed between the yoke 126 and the opposite side of the hollow member. that consisted of. Inside the movable member 138, a room or space 142 is provided.
There is provided a through hole having a diaphragm 140 that connects the inner space of the hollow member 136 with the inner space. The attachment to the housing is performed by fixing the hollow member 136 to the housing 111 with a stopper member (not shown), and the connection with the yoke 126 is performed by connecting the movable member 138 to the yoke 126.

The positioning of the head is performed by the spindle motor 1
By operating the disk drive 18 and rotating the disk 115 together with the spindle 116, a current is supplied to the coil 124 of the actuator to move the carriage 121, and the current supplied to the coil 124 is controlled.

When the head seek is performed, the carriage 1
21 receives a reaction force due to the seek force obtained by the electromagnetic action of the coil 124 and the magnet inside the yoke 126. However, as in the previous embodiment, the linear bearing 21 is disposed in the in-plane direction of the disk 115. 131 releases the reaction force generated by the head seek, and the housing 11
The reaction force transmitted to the spindle 116 via 1 is reduced, and the positioning accuracy is improved by preventing the spindle vibration. Even if a reaction force causing resonance of the magnetic circuit composed of the magnet and the yoke 126 is generated by the head seek, the damping force of the air spring 130 is largely obtained by the throttle 140, so that the magnification and the amplitude are reduced. It is small and can increase the extra dimensions against the vibration of the magnet, reduce the clearance between the magnetic circuit and other parts, and realize cost reduction and miniaturization of HDA.

[0051] In addition, the yoke 126 and the housing 11 1
And the coil spring 132 disposed between the
4 and the magnet in the yoke 126 are maintained in a relative position, and interference between the yoke and other components is prevented. Since there is no impact generated by the interference, there is no influence by the reaction force generated by the head seek. Therefore, the positioning of the head can be performed with extremely high accuracy.

FIG. 6 shows another embodiment of the present invention, and shows still another example of the configuration of a magnetic disk drive of the type in which the head moves linearly in the radial direction of the disk.

The housing 211 is mounted on the apparatus frame 214 via the rubber cushion 213. The housing itself consists of two parts, which are fastened by bolts. Inside the housing, a disk, a drive mechanism for supporting and rotating the disk, a head assembly including a head for writing and reading information to and from the disk, a carriage for supporting the head assembly, and moving the disk on the head A mechanism for guiding the carriage so as to perform the operation is accommodated.

The disk 215 is fitted and fixed to a spindle 216, and the spindle is held by a spindle bearing 217 in a housing 211. The spindle motor 218 is installed in the housing 211 couples the shaft to the spindle 216. The head 219 is attached to the guide arm 220 via a gimbal, and the guide arm is installed on the carriage 221 . The carriage 221, the roller 222 in this by rolling on rails 223 supported on housing 211, thereby moving the head 219 in the radial direction of the disk 215. The carriage is driven by an actuator. The actuator moves the carriage by the electromagnetic action of the coil and the magnet.
In, with up each magnet to the housing 211
To have.

In the magnetic disk drive of this embodiment,
A yoke 226 carrying a magnet in the actuator is attached to the housing 211 via a guide such as a linear bearing 231 having low frictional resistance so as to be movable in the same direction as the carriage 221 . Yoke 226 is attenuated vibration by the air spring 230 disposed between the housing 211, so that the magnets do not interfere, such as the carriage 221, the coil 224 on the carriage by a coil spring 232 disposed between the housing 211 It has become .

The air spring 230 is provided between the yoke 226 and the flexible hollow member 237 and the end of the hollow member opposite to the end wall of the housing, similarly to the magnetic disk drive described in connection with the previous embodiment. It comprises a movable member 238 . The air spring 230 is arranged outside the housing 211 and attached to the frame 214 of the magnetic disk drive. Fig. 1
And similarly to the air spring in the magnetic disk device shown in FIG. 2, it is fixed to the hollow member 237 to the apparatus frame 214 by a retaining member which is not shown. The connection with the yoke is made by connecting the rod 243 extending from the movable member 238 to the yoke 226 via an opening in the end wall of the housing 211 and a seal 244 fixed to the housing 211.

The positioning of the head is performed by the spindle motor 2
18, the disk 215 is rotated together with the spindle 216, a current flows through the coil 224 of the actuator, the carriage 221 is moved, and the current flowing through the coil 224 is controlled.

When the head seek is performed, the carriage 2
The reference numeral 21 receives a reaction force because a seek force is obtained by an electromagnetic action between the coil 224 and the magnet in the yoke 226. However, the linear bearing 231 disposed in the in-plane direction of the disk 215 allows the reaction force generated by the head seek to escape, reduces the reaction force transmitted to the spindle 216 via the housing 211, and does not cause spindle vibration. Thus, the positioning accuracy is improved. Even if a reaction force causing resonance of the magnetic circuit including the magnet and the yoke 226 is generated by the head seek, the air spring 23
Since a large damping force of 0 is obtained by the diaphragm 240, the magnification and the amplitude are small, the dimension can be increased with respect to the amplitude of the magnet, the clearance between the magnetic circuit and other components can be designed to be small, and the cost and the size of the HDA can be reduced. realizable.

Further, the yoke 226 and the housing 212
And the coil spring 232 disposed between the
And the relative position of the magnet in the yoke 226
Since the interference between the yoke and other components is prevented and there is no impact generated by the interference, the head can be positioned with extremely high accuracy in combination with being not affected by the reaction force generated by the head seek.

Further, in the magnetic disk drive of this embodiment, since the air spring 230 is disposed outside the housing 211, the damping force of the air spring 230 is
16, the positioning accuracy of the head 219 can be further improved as compared with the other embodiments.

FIG. 7 shows another embodiment of the present invention, and shows an example of a magnetic disk drive of the type in which the head is positioned by a swing arm which pivots around a point outside the disk.

Although not shown, the housing 311 is composed of two parts, is fastened by bolts, and is installed on the apparatus frame via rubber cushions. Inside the housing, a disk, a drive mechanism for supporting and rotating the disk, a head assembly including a head for writing and reading information to and from the disk, and a swing arm for supporting the head assembly are housed.

The disk 315 is fitted and fixed to the spindle 316. The spindle is held by a spindle bearing 317 incorporated in the housing 311. The spindle motor 318 is mounted on the housing 311 and has a shaft connected to the spindle 316. The head 319 is attached to the guide arm 320 via a gimbal. The guide arm 320 is supported by the swing arm 321.

The swing arm is arranged inside the housing 311 in parallel with the spindle 316 and is fitted and fixed to a shaft 323 held by a bearing 322 in the housing. The rotation of the shaft 323 causes the head 319 to move on the disk. I'm making it. Actuator for driving the swing arm, the coil 324 to the shaft 323, only with up each magnet 325 in the yoke 326 to rotate the shaft 323 by the electromagnetic action of the coil and the magnet, the swing arm 32
1 is swinging.

In the magnetic disk drive of this embodiment, the yoke 326 carrying the magnet 325 of the actuator is attached to the housing 311 so as to be swingable in the same direction as the swing arm 321 by a bearing 331 arranged coaxially with the shaft 323. is, retain the relative positions of the magnet 325 and the coil 324 on the carriage by a coil spring 332 disposed between the housing 311 is positioned such thrust from falling
You. The yoke 32 is used when positioning the head.
6 is attenuated by the air spring 330 between the housing 311 and the housing 311.

The shaft 32 having the swing arm 321
3 extends outside the housing 311, and a coil 324 is fixed to an extended end thereof. Magnet 325
Is held by a bearing 331 located in the housing 311 so as to be coaxial with the shaft 323, and can rotate independently of the shaft 323. The coil spring 332 is connected to the yoke 326 and the housing 3
11 are arranged.

The air spring 330 is provided between the yoke 326 and the flexible hollow member 337 and the end of the hollow member opposite to the end wall of the housing, similarly to the magnetic disk drive described in connection with the previous embodiment. A movable member 3
It consists of 38. For mounting to the housing,
As with the magnetic disk drive of the previous embodiment, the hollow member 33
The housing 311 is provided with a stop member (not shown).
By fixing the yoke 326 to a member extending from
Binding to it is done by coupling the movable member 338 in the yoke 326.

The positioning of the head is performed by the spindle motor 3
18 by operating the disk 315 together with the spindle 316 to apply current to the actuator coil 324 to move the swing arm 321 and to control the current flowing to the coil 324.

When the head seek is performed, the swing arm 321 is swung by the electromagnetic action of the coil 324 and the magnet 325 and receives a reaction force.
At this time, in the magnetic disk drive of this embodiment, the bearing 331 allows the reaction force generated by the head seek to escape, reduces the reaction force transmitted to the spindle 316 via the housing 311 and prevents the spindle vibration. Improves positioning accuracy. Even if a reaction force that causes resonance of the magnetic circuit including the magnet and the yoke 326 is generated by the head seek, since the damping force of the air spring 330 is largely obtained by the throttle 340, the magnification and the amplitude are increased. Is small,
Increase in the size of the magnet itself against the vibration of the magnet,
The clearance between the magnetic circuit and other components can be designed to be small, and cost reduction and miniaturization of HDA can be realized.

Further, the yoke 326 and the housing 311
A coil spring 332 disposed between the magnet 325 and the coil 324 keeps a relative position between the magnet 325 and the coil 324 and prevents interference between the yoke and other components. In combination with being unaffected by force, the head can be positioned with extremely high accuracy. Yoke 326 is bearing 3
Since the yoke 326 can be moved with low friction by being held by the base 31, the component force due to the friction of the reaction force generated by the head seek received by the magnetic circuit is transmitted to the spindle 316 via the housing 311 and causes the spindle 316 to vibrate. The phenomenon can be minimized.

The flexible hollow member 337 constituting the air spring 330 is sandwiched between the housing 311 and the movable member 338 disposed inside the housing 311 so as not to be deformed in the lateral direction . . That is, since the lateral deformation is prevented without any special member, the structure of the air spring 330 is simplified,
0 can be constructed compactly, moreover, because the strain due to deformation is small, high reliability and service life have long.

Since the flexible hollow member 337 is made of fluorine rubber which does not easily generate gas, and the attenuation is performed by using the air inside the housing, the inside of the housing is kept clean and the head and the disk surface are not contaminated. .

[0073]

As described above, the magnetic disk drive according to the present invention can reduce the vibration and shock generated on the disk during head seeking, and can perform the positioning of the head with high accuracy.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of a magnetic disk drive of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a laterally enlarged sectional view showing details around a carriage of the embodiment of FIG. 1;

FIG. 4 is an enlarged longitudinal sectional view showing details around a carriage of the embodiment of FIG. 1;

FIG. 5 is a sectional view showing another embodiment of the magnetic disk drive of the present invention.

FIG. 6 is a sectional view showing still another embodiment of the magnetic disk drive of the present invention.

FIG. 7 is a sectional view showing still another embodiment of the magnetic disk drive of the present invention.

FIG. 8 is a sectional view of a conventional magnetic disk drive.

FIG. 9 is a diagram for explaining vibration characteristics in a conventional magnetic disk drive.

[Explanation of symbols]

11, 111, 211, 311 Housing 15, 115, 215, 315 Disks 16-18, 116-118, 216-218, 316-318 Disk drive means 19, 119, 219, 319 Heads 21, 121 , 221, 321 ... means for supporting the head assembly 22, 23, 122, 123, 222, 223, 322, 323 ... means for guiding the supporting means 26, 126, 226, 326 ... means for guiding the housing side member 30, 130, 230, 330 ... air spring 37, 137, 237, 337 ... hollow member 40, 140, 240, 340 ... throttle

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takeshi Takahashi 2880 Kozu, Odawara-shi, Kanagawa Pref. Hitachi, Ltd. Storage Systems Division (56) References Patent 2813268 (JP, B2) (58) Fields investigated (Int .Cl. ⁶ , DB name) G11B 25/04 G11B 21/02

Claims (5)

(57) [Claims] 1. A disk, a drive mechanism for supporting and rotating the disk, a head assembly including a head for writing and reading information to and from the disk, a mechanism for supporting the head assembly, and a head for moving on the disk A mechanism that guides the support mechanism so as to make it work, a housing that carries these mechanisms, an actuator that includes a coil and a magnet, one of which is supported by the support mechanism and the other that is supported by the housing, The movement in the same direction as the movement direction is made to the member on the housing side of the actuator , and
A guide mechanism that is supported at both ends in Ujingu, and an air spring having an aperture to actuator damping vibrations occurring members on the housing side of the actuator by a reaction force generated when was made the moving head A magnetic disk drive, comprising: 2. The magnetic member according to claim 1, wherein the member on the support mechanism side of the actuator includes a spring between the housing and a member that regulates a relative positional relationship with a member around the support member. Disk device. 3. An air spring, comprising: a flexible hollow member; a stationary member disposed on one side of the hollow member for specifying a deformation direction of the hollow member; and an air spring disposed on a housing side of the actuator opposite to the stationary member. 3. The magnetic disk drive according to claim 1, comprising a movable member coupled to a certain member, wherein the aperture is provided on one of the movable member and the stationary member. 4. The magnetic disk drive according to claim 1, wherein the air spring is disposed outside the closed structure of the magnetic disk drive. 5. The magnetic disk drive according to claim 1, wherein the stationary member is constituted by a housing.