JP2010027135A - Disk device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely prevent collision between an actuator and a recording disk when an impact is applied due to fall or the like. <P>SOLUTION: A magnetic disk 100 includes a base part 11, a magnetic disk 1, a magnetic head 3, an actuator 10, and a collision prevention part 20. The collision prevention part 20 includes an arm part and a support fixing part. The arm part includes a displacement regulation part arranged a predetermined space apart from the actuator 10 so that one end regulates displacement of a predetermined amount or more in the rotational axis direction of the actuator 10. The support fixing part includes a support part for supporting the arm part in one end, and the other end is fixed to a casing. The arm part includes a flange part having a gravitational center of the arm part in the other end on a side opposite to one end including the displacement regulation part with respect to the support part. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a disk device having a collision prevention mechanism between an actuator and a recording disk.

  In recent years, high-density recording of magnetic disk devices has made it possible to record large-capacity data such as audio and visual data even in miniaturized magnetic disk devices, and information recording in mobile devices that handle these data The market for devices is expanding. As a condition for mounting a magnetic disk device in such a mobile device, high impact resistance can be mentioned. When it is mounted on a mobile device, it must be carried. Therefore, it is predicted that a high impact will be applied to the magnetic disk device depending on the handling. Even under such conditions, there is an increasing demand for preventing at least corruption of stored data.

  Normally, as shown in FIG. 11, the magnetic disk device 200 is laminated and fixed at regular intervals on a spindle hub (not shown) rotated by a spindle motor 205 via a spacer disk (not shown). A plurality of magnetic disks 201 (two in FIG. 11) are provided. On the other hand, a magnetic head 241 for performing recording / reproduction on the recording disk is mounted at the tip of one end of the actuator 245. A coil 247 of a voice coil motor 246 (hereinafter referred to as VCM 246) is provided at the other end of the actuator 245. As a result, the magnetic head 241 can be rotated around the rotation center axis 245a of the actuator 245 by the driving force of the VCM 246, and can move in the radial direction on the magnetic disk 201. When the magnetic disk 201 is rotated by the rotation of the spindle motor 205, the magnetic head 241 slightly floats from the disk 201 due to the air flow generated between the surface of the magnetic disk 201 and the magnetic head 241.

  Further, data recorded on the magnetic disk 201 is recorded as magnetic information on a data track formed concentrically with the rotation center of the magnetic disk 201. The magnetic head 241 can access an arbitrary data track by the operation of the spindle motor 205 and the VCM 246, that is, the rotation of the magnetic disk 201 and the movement of the magnetic head 241.

  The flying height of the magnetic head 241 with such a configuration from the recording surface of the magnetic disk 201 is about several tens of nanometers. For this reason, if dust or dirt enters between the magnetic head 241 and the magnetic disk 201, the magnetic head 241 and the magnetic disk 201 are damaged, causing a failure. Therefore, the magnetic disk device 200 is assembled in a clean room. After the assembly, the magnetic disk device 200 is sealed with a cover (not shown) and an airtight member (not shown).

  Here, the data corruption situation can be roughly divided into several cases. For example, when the magnetic head 241 is damaged, all data cannot be read, or a specific area on the magnetic disk 201 is physically damaged, and only this portion of data is damaged. There is.

  The former cause is a phenomenon in which the magnetic head 241 is damaged when the magnetic disk 201 collides with the magnetic head 241 in the retreat area on the magnetic disk 201 when a large impact is applied in a non-operating state. . This phenomenon is greatly improved by providing a ramp load mechanism 210 that is a mechanism for retracting the magnetic head 241 to the outside in the radial direction of the magnetic disk 201 in a non-operating state or a state in which no data is read or written. Has been.

  Next, the latter cause will be described with reference to FIGS. The actuator 245 includes a suspension 207, an arm 206, and a VCM 246. As indicated by the hatched area in FIG. 13, there is an area where the magnetic disk 201 and the suspension 207 overlap in the plane direction. For this reason, when an impact is applied to the apparatus, the suspension 207 may collide with the magnetic disk 201 as shown in FIG. In this case, the magnetic disk 201 is physically damaged, and data of the damaged part is lost. Further, even in an area where there is no data, the magnetic film or the like formed on the surface of the magnetic disk 201 is peeled off, causing damage by intervening between the magnetic head 241 and the magnetic disk 201.

As a countermeasure against such a problem, it is effective to arrange the magnetic disk 201 and the arm 206 so as not to overlap each other. However, there is a dimensional limitation associated with the downsizing of the device, which makes it difficult to form the arm 206 in a complicated shape. Under such circumstances, when the actuator 245 bends (displaces) in the direction of colliding with the magnetic disk 201 due to an impact, the displacement is regulated by locking a part of the actuator 245. A disk device is disclosed (for example, Patent Document 1).
JP 11-345471 A (published December 14, 1999)

  However, a member for locking a part of the actuator 245 in the magnetic disk device 200 (hereinafter referred to as a displacement restricting member 209) is magnetic because of a structural problem of the magnetic disk device 200 and a space problem accompanying miniaturization. It can be provided only outside the disk 201 in the radial direction (see FIG. 13). Therefore, when the actuator 245 is displaced, this member can be locked to a region of the actuator 245 that does not overlap the magnetic disk 201, but the member is engaged with the region that overlaps the magnetic disk 201. I can't stop. For this reason, as shown in FIG. 14, at the time of displacement due to an impact, torsion occurs between a portion locked by the displacement restricting member 209 of the actuator 245 and a portion not locked, and this twisted portion is a magnetic disk. There is a risk of colliding with 201.

  It is an object of the present invention to provide an actuator and a disk that are capable of being twisted between a portion locked by a member that restricts displacement of the actuator and a portion not locked when the actuator is bent by an impact. It is an object of the present invention to provide a disk device capable of reliably preventing a collision with the disk.

  A disk device according to a first invention includes a housing, a recording disk, a head, an actuator, and a collision prevention unit. The recording disk is rotatably mounted inside the housing. The head records information on the recording disk and / or reproduces information on the recording disk. The actuator has a head mounted at one end and is rotatably fixed to the housing so that the head moves in the radial direction of the recording disk at the other end. The collision preventing unit includes an arm unit and a support fixing unit. The arm portion includes a displacement restricting portion disposed at a predetermined interval with respect to the actuator such that one end portion restricts a displacement of a predetermined amount or more in the rotation axis direction of the actuator. The support fixing portion has a support portion for supporting the arm portion at one end portion, and the other end portion is fixed to the casing. The arm portion has the center of gravity of the arm portion at the other end portion provided on the opposite side to the one end portion including the displacement restricting portion with respect to the support portion.

  Here, in a disk device comprising a housing, a recording disk, a head, and an actuator having the head mounted on one end and the other end rotatably fixed to the housing, In order to reliably prevent a collision between the recording disk and an actuator at a predetermined position when the disk device falls, the following configuration is adopted.

  The disk device includes a recording disk and a head in an enclosure, and an actuator that mounts the head at one end. Further, the other end of the actuator is fixed so as to be rotatable with respect to the housing, and by this rotation, the head moves in the radial direction of the recording disk. In order to prevent a collision between the actuator and the recording disk, a collision prevention unit is provided. This collision prevention part has an arm part and a support fixing part. One end portion of the arm portion is configured to include a displacement restricting portion. Specifically, the displacement restricting portion is arranged with a predetermined interval with respect to one surface of the actuator. The displacement restricting portion restricts a displacement of a predetermined amount or more in the rotation axis direction of the actuator. The other end of the arm has the center of gravity of the arm including the displacement restricting portion. The fixed support portion has a support portion that supports the arm portion at one end portion, and the other end portion is fixed to the housing.

  Here, the recording disk is for recording information or has information recorded in advance, and may be, for example, a magnetic disk or an optical disk. The collision prevention unit is provided so that the actuator does not collide with the recording disk due to the impact of the fall of the disk device, and in particular, for preventing the collision when the disk device is not operating. It is. The predetermined amount is a distance shorter than the distance between the actuator and the recording disk in a region where the actuator and the recording disk overlap in the rotation axis direction of the recording disk. In addition, the other end portion of the arm portion having the center of gravity means that, for example, the other end portion provided on the opposite side to the support portion is heavier than the one end portion having the displacement restricting portion. It is configured.

  With such a configuration, for example, when the actuator is displaced in a direction of colliding with the recording disk due to an impact at the time of collision, the arm is provided on one side including the displacement restricting portion on the opposite side with the support portion interposed therebetween. And the other end of the support behaves like a lever with the support portion as a fulcrum. Specifically, due to the impact, the end having the center of gravity of the arm portion is displaced as a force point in the same direction as the displacement direction of the actuator, so the displacement restricting portion is like a lever with the supporting portion as a fulcrum, The actuator is displaced as an action point in the opposite direction to the actuator displacement direction. In other words, when the actuator is deformed in the direction of the recording disk, the collision prevention unit can actively approach the actuator and make the deformation of the actuator smaller than the conventional one. Therefore, when an impact that causes the actuator and the recording disk to collide is applied to the disk device, the displacement restricting portion locks the surface on the displacement direction side of the actuator at a position farther from the recording disk than in the past. It becomes possible.

  As a result, during normal operation, the collision prevention unit prevents the actuator from being obstructed, that is, secures the actuator rotation space, and when an impact is applied, the actuator is displaced. It becomes possible to limit to below the fixed amount. Therefore, it is possible to reduce the size of the apparatus while reliably preventing a collision between the recording disk and the actuator.

  A disk device according to a second invention is the disk device according to the first invention, wherein the arm portion has a weight portion heavier than the displacement restricting portion at the other end portion.

  Here, in the arm portion, the weight portion provided at the other end is heavier than the displacement restricting portion provided at one end.

  Thereby, the gravity center of an arm part can be located in the edge part side in which the weight part is provided. As described above, since the displacement restricting portion and the weight portion can operate like a lever having the support portion as a fulcrum, when the actuator is displaced in the direction of colliding with the recording disk, the displacement restricting portion is It becomes possible to restrict the displacement by locking the actuator.

  As a result, it is possible to prevent a collision between the actuator and the recording disk with a simple configuration.

  A disk device according to a third invention is the disk device according to the first or second invention, wherein the bending rigidity of the arm portion in the rotation axis direction is higher than the bending rigidity of the support portion.

  Here, when the bending rigidity of the arm part and the bending rigidity of the support part are compared in the direction of the rotation axis of the actuator, the arm part has higher bending rigidity.

  Here, the bending rigidity is an index indicating the difficulty of bending of the substance. For example, the high bending rigidity means that the bending is difficult.

  Thereby, when the impact with respect to the rotation axis direction of the actuator is applied to the disk device, the impact preventing portion can absorb the impact to the support portion rather than the arm portion. That is, the inertial force due to the impact is more strongly applied to the end portion on the side having the center of gravity of the arm portion than the displacement restricting portion, so that the support portion is curved toward the end portion side on the side having the center of gravity. For this reason, the end on the side having the center of gravity moves away from the actuator, and the displacement restricting portion approaches the actuator. Therefore, the displacement restricting portion and the end portion on the side having the center of gravity can reliably operate like a lever with the support portion as a fulcrum.

  As a result, when an impact is applied such that the actuator collides with the recording disk, the displacement restricting section can reliably operate so as to approach the actuator. Therefore, the displacement restricting portion can lock the actuator so as not to collide with the recording disk.

  A disk device according to a fourth aspect of the present invention is the disk device according to any one of the first to third aspects of the present invention, wherein the support portion includes a bending rigidity reduced portion. This bending rigidity reduction part reduces the bending rigidity of the support part in the rotation axis direction.

  Here, in order to actively lower the bending rigidity of the support portion in the rotation axis direction, the support portion includes a bending rigidity reduced portion.

  Here, the bending rigidity reduced part is a part formed thinner than other parts of the collision preventing part, for example, when the collision preventing part is integrally molded.

  Thus, the arm portion and the fixed support portion can be reliably operated like a lever with a simple configuration without impairing the rigidity of other portions.

  As a result, it is possible to easily form the collision prevention unit, and it is possible to provide an inexpensive and highly reliable disk device.

  A disc device according to a fifth invention is the disc device according to any one of the first to fourth inventions, wherein the arm portion has a rib from one end portion to the other end portion. .

Here, ribs are formed in order to increase the bending rigidity of the arm portion.
Thereby, the bending rigidity of an arm part can be made comparatively high with respect to a support part. Therefore, the arm portion and the fixed support portion can be reliably operated like a lever with a simple configuration without impairing the rigidity of other portions.

  As a result, it is possible to easily form the collision prevention unit, and it is possible to provide an inexpensive and highly reliable disk device.

  A disk device according to a sixth invention is the disk device according to any one of the first to fifth inventions, wherein the same number of actuators and displacement regulating portions are provided.

Here, the number of arms corresponding to the number of actuators is provided.
Here, some disk devices include one recording disk or two or three recording disks. That is, when a plurality of recording disks are provided, a plurality of actuators are also provided. Therefore, the same number of displacement restricting portions as the number of actuators are required. In addition, even when the collision prevention unit includes a plurality of displacement regulating units, the end portion on the side having the center of gravity may be one.

As a result, even in a disk device having a plurality of recording disks, it is possible to prevent the actuators corresponding to each of them from colliding with each recording disk.
As a result, it is possible to provide a large capacity and highly reliable disk device.

  A disc device according to a seventh invention is the disc device according to any one of the first to sixth inventions, wherein the natural frequency of the arm portion in the rotational axis direction is a maximum frequency during operation. Bigger than.

  Here, the natural frequency of the arm portion in the rotation axis direction is larger than the maximum frequency during the operation of the disk device.

  Here, the maximum frequency of the disk device indicates the maximum vibration generated in the device due to rotation of a spindle motor or a stepping motor provided in the device.

  As a result, even when the disk device vibrates at the maximum frequency of the disk device, it is possible to prevent the arm portion from resonating. Therefore, it is possible to prevent the arm portion from colliding with another member such as an actuator or hindering the rotation of the actuator. Further, when an impact is applied, it is possible to prevent a phase shift from occurring in the response displacement with respect to the vibration of the arm portion or the impact acceleration in the operation using the support portion as a fulcrum.

  As a result, even in the operation state in which the spindle motor or the like rotates, it is possible to restrict the rotational axis direction displacement of the actuator more than a predetermined amount. Therefore, it is possible to reliably prevent damage to the recording disk due to contact between the actuator and the recording disk and improve reliability, and it is possible to provide a disk device with high impact resistance. Furthermore, even when vibrations or impacts are applied during transportation, displacement of a predetermined amount or more in the rotation axis direction of the actuator can be restricted. Therefore, it is possible to reliably prevent damage to the recording disk due to contact between the actuator and the recording disk and improve reliability, and it is possible to provide a disk device with high impact resistance.

  A disk device according to an eighth aspect of the present invention is the disk device according to any one of the first to seventh aspects, wherein the natural frequency of the arm portion in the rotational axis direction is 500 Hz or more.

  Here, normally, the disk device has a range that can guarantee the vibration and impact during non-operation. This range is, for example, 5 to 500 Hz for vibration and 500 Hz for impact. The value of 500 Hz is a value higher than the maximum frequency during operation in a normal disk device.

As a result, the arm portion does not resonate even when the shock is not in operation if the vibration frequency is within the shock resistance range guaranteed in a general disk device. That is, the arm can be prevented from resonating with the frequency of the impact as long as the impact is not given to the disk device itself being damaged. Accordingly, it is possible to prevent damage to the recording disk due to contact between the actuator and the recording disk even during non-operation.
As a result, it is possible to provide a disk device with higher reliability than in the past.

  A disk device according to a ninth aspect is the disk device according to any one of the first to eighth aspects, wherein the natural frequency of the arm portion in the rotational axis direction is 700 Hz or more.

  As a result, the arm portion does not resonate even with an impact having a frequency higher than the maximum frequency guaranteed at the time of non-operation defined in a general disk device. Therefore, it is possible to prevent damage to the recording disk due to contact between the actuator and the recording disk more reliably than before, regardless of whether it is in operation or not.

  As a result, it is possible to provide a disk device with higher reliability than in the past.

  According to the present invention, it is possible to reliably prevent a collision between an actuator and a recording disk when an impact such as a drop collision is applied.

  A magnetic disk device 100 according to an embodiment of the present invention will be described below with reference to FIGS.

[Configuration of Entire Magnetic Disk Device 100]
As shown in FIGS. 1 to 3, the magnetic disk device 100 includes a base (housing) 11, a top cover 12, a magnetic disk (recording disk) 1, a spindle motor 2, an actuator 10, and a collision. The prevention unit 20, the ramp load 9, and the control unit 14 are provided.

  The base part 11 is a box-shaped member having an open upper surface, and stores the parts such as the magnetic disk 1 and the actuator 10 therein. The base 11 is preferably formed using a rigid body that is resistant to impact.

  The top cover 12 covers the opening of the base part 11 and is fixed to the base part 11 by, for example, screwing, and seals each member stored in the base part 11.

  The magnetic disk 1 is a disk-shaped recording medium for recording information using a magnetic phenomenon. The recording area of the magnetic disk 1 has a plurality of circumferential tracks from the inner periphery to the outer periphery. As shown in FIG. 4, a plurality of servo areas A and data areas B are formed in each track. Has been.

  The spindle motor 2 is fixed to the base unit 11 as a rotating shaft of the magnetic disk 1, and rotates the magnetic disk 1 by rotating the spindle motor 2 at the number of rotations controlled by the control unit 14.

  The actuator 10 has a magnetic head 3, an arm 4, a rotating shaft 5, a suspension 6, a voice coil motor 7, and a base plate 15 (see FIG. 2).

  The rotation shaft 5 is a rotation shaft of the arm 4 and is fitted so as to be rotatable so that the axial direction is perpendicular to the base portion 11.

  The base plate 15 has a substantially central portion fixed to the rotating shaft 5, and one end of the arm 4 is fixed to one end. The other end of the base plate 15 is formed so as to be interlocked with the voice coil motor 7.

  As described above, one end of the arm 4 is fixed to the base plate 15, and the suspension 6 is fixed to the other end.

  As described above, one end of the suspension 6 is fixed so as to overlap the arm 4, and the magnetic head 3 is mounted on the other end. The suspension 6 is bent in the direction of the magnetic disk 1 and presses the magnetic head 3 against the surface of the magnetic disk 1.

  As described above, the magnetic head 3 is mounted on the tip of the suspension 6, and a reproducing head (not shown) that reproduces data magnetically recorded on the magnetic disk 1, and on the magnetic disk 1. And a recording head (not shown) for recording data. The magnetic head 3 combining these records and reproduces information on an arbitrary track on the magnetic disk 1.

  The voice coil motor 7 is a motor that converts electric energy into a rotational motion, and includes a plate-like magnet disposed above and below and a coil disposed between the magnets. The voice coil motor 7 is configured to be interlocked with the base plate 15. That is, the actuator 10 is rotated by the power of the voice coil motor 7 to move the magnetic head 3 in the radial direction of the magnetic disk 1.

  With the configuration as described above, the magnetic head 3 can be moved in the radial direction on the rotating magnetic disk 1 in a floating state. As a result, the magnetic head 3 can be positioned on the designated track, and information can be recorded and reproduced in an arbitrary area. The magnetic head 3 moves on the surface of the magnetic disk 1 at a predetermined interval so as not to contact the magnetic disk 1 in a recording or reproducing operation state, and radially outside the magnetic disk 1 in a non-operating state. Evacuate to.

  The ramp load 9 is a member for preventing a collision between the magnetic head 3 and the magnetic disk 1 in a non-operating state or the like, and is installed on the outer side in the radial direction of the magnetic disk 1. Specifically, the ramp load 9 moves from the magnetic disk 1 to the magnetic head in the direction of the rotation axis 5 of the actuator 10 as the actuator 10 rotates in the direction away from the magnetic disk 1 outward in the radial direction of the magnetic disk 1. 3 has an inclined portion that locks the tip portion of the suspension 6 so that the distance 3 moves away.

  That is, the ramp load 9 can move the tip portion of the suspension 6 locked to the inclined portion away from the surface including the surface of the magnetic disk 1 by the rotation of the actuator 10. Thus, in a state where the tip end portion of the suspension 6 is locked, the magnetic head 3 is not in contact with members other than the mounted suspension 6.

  With such a configuration, it is possible to prevent a collision between the magnetic head 3 and the magnetic disk 1 in a state where the magnetic head 3 is positioned outside the magnetic disk 1 in the non-operating state.

  The collision prevention unit 20 is magnetic when the arm 4 is bent due to an impact such as when the magnetic disk device 100 falls and collides in a state where the magnetic head 3 is positioned outside the magnetic disk 1 in a non-operating state. It is a member for preventing a collision with the disk 1 and is fixed to the base 11 on the lower side of the arm 4. The collision prevention unit 20 will be described in detail below.

[Configuration of collision prevention unit 20]
The collision prevention unit 20 is integrally molded to include polyacetal as a material, and includes an arm portion 21 and a support fixing portion 22 as shown in FIG. The arm portion 21 has a displacement restricting portion 23 and a weight portion 24. The support fixing part 22 has a fixing part 25 and a support part 26.

  The fixing part 25 is a member for fixing the entire collision prevention part 20 to the base part, and has a plate shape. Specifically, the fixing portion 25 has a screw hole 25a. By passing one screw through the screw hole 25a and a screw hole (not shown) formed in the base portion 11, the fixing portion 25 has a base. It is fixed to the base part 11.

  The support portion 26 has a rectangular bar shape and is formed to be thinner than any portion of the arm portion 21. Further, the support portion 26 is integrally formed in a substantially vertical upward direction from the upper surface of the fixed portion 25, and supports the arm portion 21 at the upper end thereof.

  The arm portion 21 is a rod-shaped member formed integrally with the support portion 26, and is formed so that its longitudinal direction is substantially parallel to the lower surface of the magnetic disk 1 or the actuator 10 in a normal state. Yes. The arm portion 21 has a support portion 26 substantially at the center, a displacement restricting portion 23 on the magnetic disk 1 side, and a weight portion 24 on the opposite side of the displacement restricting portion 23 with the support portion 26 interposed therebetween. Yes.

  Further, as described above, the arm portion 21 is formed of the same material as the support portion 26 and is formed thicker than the support portion 26. For this reason, the arm portion 21 has a bending rigidity higher than that of the support portion 26.

  The arm portion 21 has a natural frequency in a vibration mode in which the displacement restricting portion 23 and the weight portion 24 move like a lever with the support portion 26 as a fulcrum among the natural frequencies. Of vibrations (eg, vibrations of each member during use or vibrations caused by a drop collision during non-operation in a range where the magnetic disk device 100 itself is not damaged) It is formed so as to be larger than the maximum frequency. Specifically, for example, when the assumed maximum frequency is 500 Hz, the natural frequency in the vibration mode is 700 Hz.

  The displacement restricting portion 23 has a rectangular bar shape, and the upper surface 23a is formed to face the lower surface side of the actuator 10 with a predetermined gap.

  The weight portion 24 is formed integrally with the displacement restricting portion 23, and is formed to have a larger volume than the displacement restricting portion 23. That is, the weight portion 24 formed of the same material as the displacement restricting portion 23 is formed to be heavier than the displacement restricting portion 23 side. Therefore, the center of gravity of the arm portion 21 is located on the weight portion 24.

[Function of collision prevention unit 20]
As shown in FIG. 6A, the collision preventing unit 20 having such a configuration has a shape in which the longitudinal direction of the arm portion 21 is substantially perpendicular to the support portion 26 in a normal operation state and a non-operation state. Is maintained. Further, the lower surface 4a of the arm 4 included in the actuator 10 is in a state of being opposed to the upper surface 23a of the displacement restricting portion 23 through a predetermined gap in a substantially parallel state.

  Further, as described above, since the natural frequency of the arm portion 21 is higher than the maximum frequency in the normal operation state, the arm portion 21 does not resonate during normal operation. Therefore, in a normal operation state (a state where no impact is applied), the rotation of the actuator 10 is not hindered, and various operations are not troubled.

  On the other hand, when an impact that causes the arm 4 to collide with the magnetic disk 1 is applied to the magnetic disk device 100, the arm 4 is deflected in the direction of the magnetic disk 1 by the inertia force of the impact, as shown in FIG. It will be displaced (displaced). At the same time, as shown in FIG. 6B, the arm portion 21 is displaced so that the weight portion 24 having the center of gravity is displaced in the direction of the base portion 11, and the displacement restricting portion 23 approaches the arm 4. This is because when the bending rigidity of the arm portion 21 is higher than the bending rigidity of the support portion 26, the weight portion 24 having the center of gravity of the arm portion 21 is displaced in the direction of the impact on the base portion 11, and the support portion 26 is bent. This is because the inertial force due to the impact can be absorbed.

  Further, due to the natural frequency relationship as described above, even when the spindle motor 2 or the like is rotating, the arm portion 21 does not resonate, so that the displacement restricting portion 23 is already at the moment when an impact is applied. There is no significant displacement. Therefore, the displacement of the displacement restricting portion 23 with respect to the impact is not delayed (the phase is shifted) with respect to the displacement of the arm 4.

  As a result, as shown in FIG. 6B, the lower surface 4 a of the displaced arm 4 is locked to the displacement restricting portion 23 before colliding with the magnetic disk 1. Therefore, it is possible to prevent the magnetic disk 1 and the arm 4 from colliding with each other.

[Features of Magnetic Disk Device 100]
(1)
As shown in FIGS. 1 to 3, the magnetic disk device 100 according to the present embodiment includes a base 11, a top cover 12, a magnetic disk 1, a spindle motor 2, a magnetic head 3, an actuator 10, and a collision. And a prevention unit 20. The magnetic disk 1 is rotatably mounted with a spindle motor 2 fixed to the base portion 11 as a rotation shaft. The magnetic head 3 records information on the magnetic disk 1 and / or reproduces information on the magnetic disk 1. The actuator 10 has the magnetic head 3 mounted on the tip of the suspension 6 provided at one end, and the base 10 is moved to the other end so that the magnetic head 3 moves in the radial direction of the magnetic disk 1. It is fixed so that it can rotate freely. The collision prevention unit 20 includes an arm unit 21 and a support fixing unit 22. The arm portion 21 has a displacement restricting portion 23 that is disposed at a predetermined interval with respect to the actuator 10 so that one end portion restricts displacement of a predetermined amount or more in the rotation axis direction of the actuator 10. The support fixing part 22 has a support part 26 that supports the arm part 21 at one end, and the other end is fixed to the casing. The arm portion 21 has a weight portion having the center of gravity of the arm portion 21 at the other end portion provided on the opposite side to the one end portion including the displacement restricting portion 23 with respect to the support portion 26.

  With such a configuration, when the actuator 10 is displaced in a direction of colliding with the magnetic disk 1 due to an impact at the time of collision, one end portion including the displacement restricting portion 23 in the arm portion 21 and the opposite side across the support portion 26 As shown in FIGS. 6 (a) and 6 (b), the weight portion 24 provided on the wing operates as an insulator having the support portion 26 as a fulcrum. Therefore, when an impact that causes the actuator 10 and the magnetic disk 1 to collide with the magnetic disk device 100 is applied, the displacement restricting portion 23 places the lower surface 4a positioned on the displacement direction side of the actuator 10 (arm 4) in the related art. It becomes possible to lock at a position further away from the magnetic disk 1 than.

  As a result, during normal operation, when the impact is applied while preventing the collision prevention unit 20 from obstructing the rotation of the actuator 10, that is, while ensuring the rotation space of the actuator 10, the actuator 10 Can be limited to a predetermined amount or less. Therefore, it is possible to prevent a collision with a simple configuration without using a complicated configuration such as using mechanical control.

(2)
In the magnetic disk device 100 according to the present embodiment, as shown in FIGS. 3 and 6A, the arm portion 21 has a weight portion 24 on the opposite side of the displacement restricting portion 23 with the support portion 26 interposed therebetween. Yes. Moreover, this weight part 24 is heavier than a displacement control part.

  Thereby, the gravity center of the arm part 21 can be located in the edge part side in which the weight part 24 is provided. As described above, since the displacement restricting portion 23 and the weight portion 24 can operate like a lever having the support portion 26 as a fulcrum, the actuator 10 is displaced in the direction of colliding with the magnetic disk 1. The displacement restricting portion 23 can lock the actuator 10 to restrict the displacement.

  As a result, the collision between the actuator 10 and the magnetic disk 1 can be prevented with a simple configuration.

(3)
In the magnetic disk device 100 of this embodiment, as shown in FIGS. 3 and 6A, the support portion 26 is formed to be thinner than any portion of the arm portion 21, and the arm portion 21 is made of the same material. Therefore, the bending rigidity of the arm portion 21 in the direction of the rotation axis 5 is higher than the bending rigidity of the support portion 26.

  As a result, when the impact of the actuator 10 in the direction of the rotation axis 5 is applied to the magnetic disk device 100, the impact prevention unit 20 can absorb the impact on the support unit 26 rather than the arm unit 21. That is, the inertial force due to the impact is more strongly applied to the weight portion 24 on the side having the center of gravity of the arm portion 21 than the displacement restricting portion 23, so that the support portion 26 is curved toward the weight portion 24 side having the center of gravity (FIG. 6). (See (b)). For this reason, the weight part 24 moves away from the actuator 10, and the displacement restricting part 23 approaches the actuator 10. Therefore, the displacement restricting portion 23 and the weight portion 24 can reliably operate like a lever with the support portion 26 as a fulcrum.

  As a result, when an impact that causes the actuator 10 to collide with the magnetic disk 1 is applied, the displacement restricting portion 23 can be operated so as to approach the actuator 10 reliably. Therefore, the displacement restricting portion 23 can lock the actuator 10 so as not to collide with the magnetic disk 1.

(4)
In the magnetic disk device 100 of the present embodiment, the natural frequency of the arm portion 21 in the direction of the rotation axis 5 is larger than the maximum frequency of the magnetic disk device 100 due to rotation of the spindle motor 2 in the operating state.

  As a result, even when the magnetic disk device 100 is vibrating at the maximum frequency of the magnetic disk device 100, it is possible to prevent the arm portion 21 from resonating. Therefore, it is possible to prevent the arm portion 21 from colliding with another member such as the actuator 10 or hindering the rotation of the actuator 10. Further, when an impact is applied, it is possible to prevent a phase shift from occurring in a response displacement with respect to vibration or impact acceleration of the arm portion 21 in an operation using the support portion 26 as a fulcrum as shown in FIG. 6B. It becomes possible.

  As a result, even in the operation state in which the spindle motor 2 or the like rotates, the displacement of the actuator 10 in the direction of the rotating shaft 5 beyond a predetermined amount can be restricted. Therefore, it is possible to reliably prevent damage to the magnetic disk 1 due to contact between the actuator 10 and the magnetic disk 1 to improve reliability, and to provide the magnetic disk device 100 with high impact resistance. Become.

(5)
In the magnetic disk device 100 of this embodiment, the natural frequency in the vibration mode of the arm portion 21 is 700 Hz.

  As a result, it is possible to prevent the arm portion 21 from resonating with respect to vibration caused by an impact during a drop collision during operation and non-operation. Therefore, the collision between the actuator 10 and the magnetic disk 1 can be prevented as long as the magnetic disk device 100 is not subjected to an impact that causes damage.

  As a result, it is possible to provide a magnetic disk device that has higher impact resistance than before and can be used with peace of mind by the user.

[Other Embodiments]
As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the summary of invention.

(A)
In the above-described embodiment, an example has been described in which the entire support portion 26 is made thinner than the arm portion 21 so that the bending rigidity of the support portion 26 is lower than the bending rigidity of the arm portion 21. However, the present invention is not limited to this.

  For example, as illustrated in FIG. 7, the collision prevention unit 30 may have a configuration in which a bending rigidity reduction unit 36 a is provided on the support unit 36. The bending rigidity reduction portion 36a is for actively reducing the bending rigidity of the support portion 36 by forming a part of the support portion 36 into a concave shape.

With such a configuration, it is possible to reliably form the support portion 36 having a lower bending rigidity than the arm portion 31. Therefore, as shown in FIGS. 8A and 8B, it is possible to perform the same operation as that of the collision prevention unit 20 shown in the above embodiment.
As a result, the same effect as described above can be obtained.

(B)
In the said embodiment, the arm part 21 demonstrated and demonstrated the example which is a structure as shown in FIG. However, the present invention is not limited to this.

  For example, as shown in FIG. 9, the collision prevention unit 40 may have a rib 47 on the arm portion 41 from the displacement regulating portion 43 to the weight portion 44.

  With such a configuration, the bending rigidity of the arm portion 41 can be easily made higher than the bending rigidity of the support portion 46.

  As a result, the arm portion 41 and the fixed support portion 42 can be reliably operated like a lever with a simple configuration without impairing the rigidity of other portions. Therefore, the same effect as described above can be obtained.

(C)
In the above embodiment, the magnetic disk device 100 has been described with an example in which each of the magnetic disk 1 and the actuator 10 is provided. However, the present invention is not limited to this.

  For example, a plurality of magnetic disks, actuators, magnetic heads, etc. may be provided. In this case, as shown in FIG. 10, it is only necessary to include a collision prevention unit 60 having the same number (three in this case) of displacement regulating units 63 as the number of actuators. The collision prevention unit 60 has three displacement restricting portions 63 on the arm portion 61 and one weight portion 64 at an end portion on the opposite side across the support portion 66.

As a result, even in a magnetic disk device having a plurality of magnetic disks, it is possible to prevent the corresponding actuators from colliding with each magnetic disk.
As a result, it is possible to provide a magnetic disk device having a large capacity and high reliability.

(D)
In the above embodiment, an example in which the collision prevention unit 20 is provided in the magnetic disk device 100 has been described. However, the present invention is not limited to this.

For example, an optical disk device may be used. In this case, the magnetic head 3 may be changed to an optical head and the magnetic disk 1 may be changed to an optical disk.
Also by this, it is possible to obtain the same effect as described above.

(E)
In the above embodiment, the example in which the collision prevention unit 20 is disposed on the lower side of the arm 4 has been described. However, the present invention is not limited to this.

For example, the collision prevention unit 20 may be disposed so as to restrict the displacement of the actuator 10 where it is most likely to be displaced by an impact. That is, as long as the suspension 6 is displaced to the most side of the magnetic disk 1 due to the impact, the displacement restricting portion 23 may be arranged to be locked at a position where the suspension 6 is locked.
Also by this, it is possible to obtain the same effect as described above.

(F)
In the said embodiment, the material which comprises the collision prevention part 20 gave and demonstrated the example which is a polyacetal. However, the present invention is not limited to this.

For example, the material constituting the collision preventing member may be a liquid crystal polymer.
Also by this, it is possible to achieve the same effect as described above.

  The disk device of the present invention has an effect that it is possible to prevent a collision between a recording disk and an actuator in a non-operating state, and therefore, a portable device in which damage is caused by contact between members due to an impact such as a drop collision. Widely applicable to mold precision machines.

1 is a perspective view showing a magnetic disk device according to an embodiment of the present invention. FIG. 2 is a side sectional view showing the magnetic disk device shown in FIG. 1. FIG. 2 is a top plan view showing the magnetic disk device shown in FIG. 1. FIG. 2 is a diagram for explaining a magnetic disk of the magnetic disk device shown in FIG. 1. FIG. 2 is a perspective view showing a collision prevention unit of the magnetic disk device shown in FIG. 1. (A) is XX sectional drawing of the magnetic disc apparatus shown in FIG. (B) is sectional drawing which shows operation | movement of the collision prevention part shown to (a). The perspective view which shows the collision prevention part which concerns on other embodiment of this invention. (A) is side surface sectional drawing of the collision prevention part shown in FIG. (B) is a side view sectional drawing which shows operation | movement of the collision prevention part shown to (a). The perspective view which shows the collision prevention part which concerns on other embodiment of this invention. The perspective view which shows the collision prevention part which concerns on other embodiment of this invention. The perspective view which shows the conventional magnetic disc apparatus. FIG. 12 is a side sectional view of the magnetic disk device shown in FIG. 11. The top view top view of the conventional magnetic disc apparatus. FIG. 14 is a YY sectional view of the magnetic disk device shown in FIG.

Explanation of symbols

1 Magnetic disk (recording disk)
2 Spindle motor 3 Magnetic head (head)
4 Arm 4a Lower surface 5 Rotating shaft 6 Suspension 7 Voice coil motor 9 Lamp load 10 Actuator 11 Base part (housing)
12 Top cover 14 Control part 15 Base plate 20 Collision prevention part 21 Arm part 22 Support fixing part 23 Displacement restricting part 23a Upper surface 24 Weight part 25a Screw hole 25 Fixing part 26 Support part 30 Collision prevention part 31 Arm part 36a Bending rigidity reduction part 36 Support part 40 Collision prevention part 41 Arm part 42 Fixed support part 43 Displacement restriction part 44 Weight part 46 Support part 47 Rib 60 Collision prevention part 61 Arm part 63 Displacement restriction part 64 Weight part 66 Support part 100 Magnetic disk device 200 Magnetic disk device 201 Magnetic disk 205 Spindle motor 206 Arm 207 Suspension 209 Displacement restricting member 210 Ramp load mechanism 241 Magnetic head 245 Actuator 245a Rotation center shaft 246 VCM
247 Coil

Claims (9)

A housing,
A recording disk rotatably mounted inside the housing;
A head for recording information on the recording disk and / or reproducing information on the recording disk;
An actuator mounted on the housing so as to be rotatable so that the head is mounted at one end and the head moves in the radial direction of the recording disk at the other end;
An arm portion including a displacement restricting portion disposed at a predetermined interval with respect to the actuator so that one end portion restricts a displacement of a predetermined amount or more in the rotation axis direction of the actuator, and one end portion A collision prevention unit having a support unit that supports the arm unit and the other end of which is fixed to the housing;
With
The disk device has a center of gravity of the arm portion at the other end portion provided on the opposite side to the one end portion including the displacement restricting portion with respect to the support portion. The arm part has a weight part heavier than the displacement restricting part at the other end part,
The disk device according to claim 1. The bending rigidity of the arm part in the rotation axis direction is higher than the bending rigidity of the support part.
The disk device according to claim 1 or 2. The support part includes a bending rigidity reduction part that reduces the bending rigidity of the support part in the rotation axis direction.
The disk device according to any one of claims 1 to 3. The arm portion has a rib from the one end portion to the other end portion,
The disk device according to any one of claims 1 to 4. The same number of the actuators and the displacement regulating portions are provided.
The disk device according to claim 1. The natural frequency of the arm in the rotation axis direction is greater than the maximum frequency during operation,
The disk device according to claim 1. The natural frequency of the arm portion in the rotation axis direction is 500 Hz or more.
The disk device according to any one of claims 1 to 7. The natural frequency of the arm portion in the rotation axis direction is 700 Hz or more.
The disk device according to claim 1.

Images