JP2003331493A - Magnetic disk drive - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnetic disk drive which can reduce the vibration of a spindle system including a disk to be pneumatically excited by rotation of the high-speed disk of the magnetic disk drive and can narrow the spacing between data tracks. <P>SOLUTION: A blade 11 which is an air introducing section disposed backward of the rotating direction of an air inlet 3a of a clamp 3 has a slope 11a heading forward of the rotating direction with respect to the axial direction from the clamp 3, an aperture forward of the rotating direction by enclosing the air inlet 3a and an extension section 11b inclining forward of the rotating direction of an SPM 5 on the side end of the outer periphery and extending in an outer peripheral direction. As a result, the circulating air flow sufficient for preventing the occurrence of the turbulence and vortex arising between the magnetic disks or between the magnetic disk and the clamp by the rotation of the high-speed magnetic disk can be generated. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk device, and more particularly to a magnetic disk device which realizes a high recording density by reducing the vibration of the magnetic disk excited by an air flow caused by the high speed rotation of the magnetic disk.

[0002]

2. Description of the Related Art A conventional magnetic disk device will be described below with reference to a perspective view of FIG. In FIG. 14, a plurality of magnetic disks 1 are laminated and inserted at equal intervals via a single sheet or a spacer into a spindle hub 92 that is rotationally driven by a spindle motor 5 (hereinafter abbreviated as SPM). The magnetic disk 1 is pressed by a clamp 93 by three screws 4 and fixed to a spindle hub 92. Magnetic heads 41 for recording / reproducing information are arranged on both sides or one side of each magnetic disk 1 so as to be rotatable in the radial direction of the magnetic disk 1 by an actuator 45. The magnetic head 41 slightly floats above the surface of the magnetic disk 1 due to the air flow generated between the surface of the magnetic disk 1 and the magnetic head 41 due to the rotation of the SPM 5. The magnetic head 41 is fixed to the tip of an actuator 45, and a flat coil 47 of a voice coil motor 46 (hereinafter abbreviated as VCM) is provided at the other end of the actuator 45. The magnetic head 41 is V
The drive force of the CM 46 causes the actuator 45 to rotate about the rotation center axis 45a, and moves on the surface of the magnetic disk 1 in the radial direction.

Information data is recorded as magnetic information on data tracks which are drawn concentrically on the surface of the magnetic disk 1. By rotating the SPM 5, that is, rotating the magnetic disk 1 and rotating the magnetic head 41, the magnetic head 41 can access a desired position on a desired data track to record or reproduce information data. That is, in order to read and write information data accurately, the magnetic head 41 needs to accurately follow the data track of the magnetic disk. The magnetic head 41 follows the data track by detecting the current position from the servo information discretely drawn at a plurality of locations on the data track at equal angular intervals, and correcting the deviation from the data track by the actuator 45. Is rotated to move the magnetic head 41. The flying height of the magnetic head 41 from the surface of the magnetic disk is about several tens of nanometers, and dust and dust intervening between the magnetic head 41 and the magnetic disk 1 damage the magnetic head 41 and the disk 1 and cause a failure. Cause. For this reason, the magnetic disk device is assembled in a clean room, and after the assembly, the housing 4
The upper surface of 3 is sealed with a cover 42 via an airtight member 44.

In recent years, information recording apparatuses are required to have various characteristics such as large recording capacity (high density), high transfer rate, high reliability, low power consumption, low cost, small size, light weight and portability. To be The magnetic disk device, which has an advantage in satisfying the convenience of the user in terms of recording amount and transfer speed, has become an indispensable information recording device for computers and the like.
It is considered that the capacity and the speed will be further increased in the future, that is, the density and the speed will be further increased, and along with that, the narrowing of the data track interval, which is a promising means for realizing those functions, and the SP.
High-speed rotation of M will continue to progress.

In order to reduce the data track interval, it is necessary to improve the positioning accuracy of the magnetic head 41 on the data track. Among the factors that hinder the high-accuracy positioning of the magnetic head 41 on the data track, it is required to reduce the shake of the SPM 5 and the magnetic disk 1 which are dominant. Of particular concern is the S shown in FIG.
Asynchronous rotational runout caused by the bearing 8 of the PM 5, a natural vibration of the spindle system, and resonance caused by matching their frequencies. First, the asynchronous rotation runout caused by the bearing 8 can be greatly reduced by using a fluid bearing whose mass production system has been established in recent years, and can be somewhat reduced by improving the processing accuracy even when a ball bearing is used. Further, the resonance between the asynchronous rotational runout of the ball bearing and the natural vibration of the spindle system can be avoided by design, and can be improved by using a fluid bearing.

Next, in order to reduce the shake due to the natural vibration of the spindle system, it is necessary to reduce the exciting force for the spindle hub including the magnetic disk or to make the structure such that the exciting force does not cause the shake. A major factor of this exciting force is the air exciting force accompanying the rotation of the magnetic disk. That is, when the SPM 5 rotates, the air in the vicinity thereof and between the laminated magnetic disks 1 and 1 also rotates and turbulence and vortex are generated. Due to this turbulent flow and vortex, an unsteady pressure difference that temporally varies near the surface of each magnetic disk 1 is generated to generate an air excitation force. When the rotation speed of the SPM 5 becomes high, the air flow generated becomes high speed, and the air exciting force becomes large. As described above, the rotation speed of the SPM 5 tends to increase due to the increase in the transfer speed, and the air excitation force also increases. Therefore, it is possible to achieve both the shake reduction due to the natural vibration of the spindle system and the high speed rotation of the SPM 5. Required. That is, the narrowing of the data track interval for high-density recording and the high-speed rotation of the SPM 5 have contradictory characteristics, and it has become a difficult technical issue to achieve both at the same time.

As one of the methods for reducing the vibration of the magnetic disk due to the natural vibration of the spindle system against the air excitation force in the conventional magnetic disk apparatus, an air flow from the inner circumference side to the outer circumference side of the magnetic disk is forcibly formed. The central balloon method has been proposed. This central blowing method will be described with reference to the sectional view showing the configuration of the central blowing type magnetic disk device of FIG. The sealed state of the magnetic disk 1 inserted into and fixed to the spindle hub 92 and the housing 43 after assembly are the same as those in the above-described conventional example, and therefore like parts are designated by like reference numerals and redundant description will be given. Is omitted. As shown in FIG. 15, in the magnetic disk device using the central blowing method, the clamp 93 is provided with an intake port 93a, and the spindle hub 92 is provided with a flow path 92c. Further, the spacer 7 is provided with an exhaust port 7f, and the spindle hub 92 is provided with an exhaust port 92f. SPM
The surface of the magnetic disk 1 rotating at a high speed and the air in the vicinity of the magnetic disk 1 rotate due to viscosity, and the centrifugal force generated thereby causes the air to move in the outer peripheral direction of the magnetic disk 1. As a result, the air in the vicinity of the magnetic disk 1 flows from the exhaust port 92f of the spindle hub 92 and the exhaust port 7f of the spacer 7 to the outer peripheral side of the magnetic disk 1, and this air lowers the atmospheric pressure in the vicinity of the inner peripheral part of the magnetic disk 1. Then, air is sucked from the intake port 93a of the clamp 93.

In this way, in the magnetic disk device, the air discharged from the exhaust port 92f and the exhaust port 7f flows from the inner peripheral side to the outer peripheral side of the magnetic disk 1, and further from the outer peripheral side to the inner wall of the housing 43. Is sucked into the suction port 93a of the clamp 93 along with and is distributed to the inner peripheral side of each magnetic disk to form a circulating air flow. In FIG. 15, this circulating air flow is indicated by a thick solid line with an arrow. The formation of this circulating air flow can prevent unsteady turbulence and vortices generated on the surface of the magnetic disk 1 and reduce the air excitation force.

[0009]

[Problems to be Solved by the Invention]
This is an easy and effective method for a large-sized magnetic disk device such as a magnetic disk having a diameter of 8 inches or 14 inches because there is a dimensional allowance in the specific configuration of the exhaust port and the flow path. However, it is not easy to realize with a magnetic disk device using a 3.5-2.5 inch magnetic disk.
This is because the SPM of the magnetic disk device and the space between the stacked magnetic disks, that is, the spacer, is smaller and thinner than the 8-inch and 14-inch ones, and the flow path and the exhaust port are necessarily small. Can only be provided. Further, the centrifugal force due to the rotation of the SPM also acts on the air near the intake port, and tries to move to the outer periphery,
The air pressure near the intake port decreases, which hinders the intake of air. Further, since there is a speed difference between the SPM and the air flow near the intake port, this also hinders the intake of air into the intake port. As a result, in the conventional central blowing method, it is not possible to secure a flow rate of air that can form a circulating air flow that prevents the generation of turbulence and vortices in the vicinity of the magnetic disk 1 that rotates at high speed.

Focusing on such a conventional problem, a spiral groove is formed in a housing facing a surface of a clamp or a magnetic disk, as disclosed in a prior art example of Japanese Patent Application Laid-Open No. 11-297037. The method of providing is proposed and it is trying to increase the flow rate of the circulating air flow. In the conventional central blowing method shown in FIG. 15, the centrifugal force that acts on the air near the intake port 93a as the SPM 5 rotates prevents the intake of air from the intake port 93a. On the other hand, in the method of the prior art of the above publication, a pressure is applied by the pumping action of the spiral groove to generate an airflow toward the inner peripheral side, that is, the vicinity of the intake port 93a, and the air is sucked from the intake port 93a. The flow rate of the air stream can be increased.

However, even with the configuration of the prior example, the SPM
5 is not sufficient to solve the problem of the speed difference between the rotation speed of No. 5 and the flow velocity of the air flow in the vicinity of the intake port 93a, and the spiral groove does not allow the air to directly flow into the intake port 93a. That is, it was necessary to further increase the flow rate of the air sucked into the intake port 93a. In order to further reduce the size, increase the capacity, and increase the speed, it has become an issue to reduce the shake of the magnetic disk due to the vibration of the spindle system caused by the air vortex and the like accompanying the high speed rotation of the small magnetic disk and the SPM. It is not easy to show a central blowing structure that can realize high-speed rotation even in a magnetic disk device of 3.5 inches or less.

The present invention provides a central blow-out type magnetic disk device which enables a circulating air flow capable of reducing the vibration of the magnetic disk excited by the air flow generated by the high speed rotation of the magnetic disk even in a small magnetic disk device. The purpose is to do.

[0013]

A magnetic disk device of the present invention is a magnetic disk for recording information, a flange portion on which the magnetic disk is to be mounted, and a disk insertion cylindrical portion into which a center hole of the magnetic disk is to be inserted. A spindle hub having, a clamp for rotatably fixing the magnetic disk integrally with the spindle hub, and a rotation of the spindle hub around an axis of rotation that is fixed to a base member such as a frame. A bearing that movably supports, a spindle motor that rotationally drives the spindle hub, and a housing that hermetically houses the above-mentioned components, and an air intake provided in the clamp in the housing as the spindle motor rotates. Inhaled through the mouth, discharged through the exhaust port provided in the spindle hub through the flow path provided in the spindle hub. In a magnetic disk device adapted to generate a circulating air flow to be sucked into the intake port again, an air introduction blade for the intake port is provided at a portion which is behind the intake port when the spindle motor rotates. To do.

According to this structure, there is an action of forcibly introducing the air in front of the air introducing portion in the spindle rotation direction from the air introducing portion provided in the clamp that rotates integrally with the SPM into the intake port. Therefore, the flow rate of the circulating air flow can be increased, and a sufficient flow rate of the circulating air flow can be secured to prevent the generation of turbulence and vortices near the magnetic disk rotating at high speed. As a result, a sufficient amount of circulating air flow is generated from the inner circumference side to the outer circumference side of the magnetic disk that rotates at high speed to suppress the generation of turbulence and vortices, reduce the air excitation force, and reduce the vibration of the magnetic disk. It can be reduced. By reducing the vibration of the magnetic disk, it is possible to provide a magnetic disk device capable of realizing high density recording.

A magnetic disk device according to another aspect of the present invention comprises a magnetic disk for recording information, a flange portion on which the magnetic disk is to be mounted, and a disk insertion cylindrical portion for inserting a center hole of the magnetic disk. A spindle hub, a clamp that rotatably fixes the magnetic disk integrally with the spindle hub, and a bearing that rotatably supports the spindle hub around an axis of rotation that is fixed to a base member. A spindle motor that rotationally drives the spindle hub, and a housing that hermetically accommodates the above-described components, and is sucked into the housing through an intake port provided in the clamp as the spindle motor rotates. It is discharged from the exhaust port provided in the spindle hub through the flow path provided in the spindle hub, and the intake port is again provided. In a magnetic disk device adapted to generate a circulating air flow to be sucked in, an air flow passage provided in a disk insertion cylindrical portion of the spindle hub has a flow path in a direction parallel to an axis of rotation of the circulating air flow. It is characterized in that it is provided so as to be inclined in a backward direction when the spindle motor rotates after the movement.

According to this structure, the air flow can obtain thrust in the axial direction by the normal force received from the side surface of the flow path provided in the spindle hub. Therefore, the action of forcibly introducing air from the intake port into the flow path occurs. As a result, it is possible to generate a sufficient amount of circulating air flow from the inner circumference side to the outer circumference side of the magnetic disk that rotates at high speed, suppress turbulence and vortex generation, and reduce the air excitation force. By reducing the vibration of the magnetic disk, it is possible to provide a magnetic disk device capable of realizing high density recording.

A magnetic disk device according to still another aspect of the present invention includes a magnetic disk for recording information, a flange portion on which the magnetic disk is to be mounted, and a disk insertion cylindrical portion for inserting a center hole of the magnetic disk. A spindle hub, a clamp that rotatably fixes the magnetic disk integrally with the spindle hub, and a bearing that rotatably supports the spindle hub with respect to a rotation axis (axis) that is fixed to a base member. A spindle motor that rotationally drives the spindle hub, and a housing that hermetically accommodates the above-described components, and is sucked into the housing through an intake port provided in the clamp as the spindle motor rotates. The air is discharged from the exhaust port provided in the spindle hub through the flow path provided in the spindle hub, and the intake air is again supplied. In a magnetic disk device configured to generate a circulating air flow that is drawn into a magnetic disk device, an air flow passage provided in a solid portion of the disk insertion cylindrical portion of the spindle hub is It is characterized in that it is provided so as to be inclined toward the outer peripheral direction of the spindle hub as the air flow advances.

According to this structure, the air flow can obtain thrust in the axial direction by the vertical drag force received from the outer peripheral side surface of the flow passage provided on the spindle hub and inclined in the outer peripheral direction. Therefore, the action of forcibly introducing air from the intake port into the flow path occurs. As a result, it is possible to generate a sufficient amount of circulating air flow from the inner circumference side to the outer circumference side of the magnetic disk that rotates at high speed, suppress turbulence and vortex generation, and reduce the air excitation force. By reducing the vibration of the magnetic disk, it is possible to provide a magnetic disk device capable of realizing high density recording.

A magnetic disk device according to still another aspect of the present invention includes a magnetic disk for recording information, a flange portion on which the magnetic disk is to be mounted, and a disk insertion cylindrical portion for inserting a center hole of the magnetic disk. A spindle hub, a clamp that rotatably fixes the magnetic disk integrally with the spindle hub, and a bearing that rotatably supports the spindle hub with respect to a rotation axis (axis) that is fixed to a base member. A spindle motor that rotationally drives the spindle hub, and a housing that hermetically accommodates the above-described components, and is sucked into the housing through an intake port provided in the clamp as the spindle motor rotates. It is discharged from the exhaust port provided in the spindle hub through the air passage provided in the spindle hub and In a magnetic disk device configured to generate a circulating air flow to be sucked into an intake port, from an exhaust port to an inner peripheral side of the magnetic disk to an outer peripheral side of an inner wall of a casing facing an outer peripheral side surface of the magnetic disk. flow,
A plurality of rectifying convex portions for rectifying the circulating air flow toward the intake port are provided along the inner wall of the housing, and the rectifying convex portions are located above the intake port with respect to the generatrix of the inner wall parallel to the central axis. It is characterized in that it is provided so as to be delayed in rotation of the clamp.

According to this structure, by the normal force received from the side surfaces of the plurality of convex portions provided on the inner wall of the housing,
The air flow can obtain thrust in the axial direction. Therefore, the action of forcibly sending the air flowing out from the outer peripheral side of the magnetic desk toward the intake port occurs. As a result, it is possible to generate a sufficient amount of circulating air flow from the inner circumference side to the outer circumference side of the magnetic disk that rotates at high speed, suppress turbulence and vortex generation, and reduce the air excitation force. By reducing the vibration of the magnetic disk, it is possible to provide a magnetic disk device capable of realizing high density recording.

A magnetic disk device according to still another aspect of the present invention is a magnetic disk for recording information, a flange portion on which the magnetic disk is to be mounted, and a disk insertion cylindrical portion for inserting a center hole of the magnetic disk. A spindle hub, a clamp that rotatably fixes the magnetic disk integrally with the spindle hub, and a bearing that rotatably supports the spindle hub with respect to a rotation axis (axis) that is fixed to a base member. A spindle motor that rotationally drives the spindle hub, and a housing that hermetically accommodates the above-described components, and is sucked into the housing through an intake port provided in the clamp as the spindle motor rotates. It is discharged from the exhaust port provided in the spindle hub through the air passage provided in the spindle hub and In a magnetic disk device configured to generate a circulating air flow that is sucked into an intake port, a portion of the inner surface of the cover that covers the housing is opposed to the surface of the uppermost magnetic disk from the outer peripheral side of the magnetic disk. It is characterized in that a lid-shaped partial annular plate is provided which forms a tunnel for guiding the air flow toward the intake port of the clamp along the inner surface.

According to this structure, the air flow toward the outer peripheral side of the magnetic disk due to the centrifugal force caused by the rotation of the magnetic disk, and the air flow along the inner wall of the housing from the outer peripheral side of the magnetic disk toward the intake port. Can be separated by a partial annular plate. Therefore, an effect of preventing the interference of both air flows traveling in opposite directions is produced. As a result, it is possible to generate a sufficient amount of circulating air flow from the inner circumference side to the outer circumference side of the magnetic disk that rotates at high speed, suppress turbulence and vortex generation, and reduce the air excitation force. By thus reducing the vibration of the magnetic disk, it is possible to provide a magnetic disk device capable of realizing high density recording.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some preferred embodiments of the magnetic disk device of the present invention will be described below with reference to the accompanying drawings. An overall configuration common to the embodiments of the magnetic disk device of the present invention will be described with reference to the perspective view of FIG. In FIG. 1, a plurality of magnetic disks 1 and 1 for storing information are stacked at equal intervals via a spacer (not shown) on a spindle hub 2 which is rotationally driven by an SPM 5, and fixed by being pressed by a clamp 3. . A magnetic head 41 for recording / reproducing information is provided on each side or one side of each magnetic disk 1 with an actuator 45.
Is arranged so as to be rotatable in the radial direction of the magnetic disk 1.

By the air flow generated between the surface of the magnetic disk 1 and the magnetic head 41 by the rotation of the SPM 5,
The magnetic head 41 flies slightly above the surface of the magnetic disk 1. The magnetic head 41 is fixed to the tip of the actuator 45, and a flat coil 47 of the VCM 46 is provided at the other end (base end) of the actuator 45. The magnetic head 41 rotates about the central axis 45a of the rotation of the actuator 45 by the driving force of the VCM 46, and moves on the surface of the magnetic disk 1 in the radial direction.

The information data is recorded as magnetic information on a data track which is drawn concentrically on the surface of the magnetic disk 1. By rotating the SPM 5, that is, rotating the magnetic disk 1 and rotating the magnetic head 41, the magnetic head 41 can access a desired position on a desired data track to record or reproduce information data. Since the flying height of the magnetic head 41 from the surface of the magnetic disk is as small as several tens of nanometers, dust between the magnetic head 41 and the magnetic disk 1 causes the magnetic head 41 and the disk 1 to be damaged, resulting in failure. Cause of. Therefore, the magnetic disk device is assembled in a clean room, and the upper surface of the housing 43 is sealed by the cover 42 and the airtight member 44 after the assembly.

A characteristic part of the present invention is a structure for increasing the flow rate of the circulating air flow accompanying the rotation of the SPM. Therefore, each of the following embodiments will be described with reference to the drawings of the mechanism for generating the circulating air flow. In addition, the same reference numerals as those of the above-mentioned overall configuration are attached to the common overall configuration parts in each embodiment, and the duplicated description will be omitted.

<< Embodiment 1 >> FIG. 2 is a perspective view of a clamp 3 showing a mechanism for generating a circulating air flow in a magnetic disk device according to Embodiment 1 of the present invention. As shown in FIG.
In the clamp 3 used in the magnetic disk device of FIG.
In the rotation of, the three air introduction blades 11 are provided at the rear. Further, the air introduction blade 11 has an inclined surface that is forward in the rotational direction from a direction parallel to the axial direction of rotation that is perpendicular to the surface of the clamp 3. The axis mentioned above refers to the axis of rotation of the spindle hub that is fixed with respect to a base member such as a frame. Furthermore, air introduction wing 1
Reference numeral 1 surrounds an intake port 3a that hits the rear in rotation, has an opening in the front in the rotational direction, and an end portion on the outer peripheral side inclines forward in the rotational direction and extends toward the outer peripheral portion 11b. have.

The operation and effect of providing the air introducing blade 11 having such a structure to the clamp 3 of the magnetic disk device of the present invention shown in FIG. 1 will be described below. First, the air introduction vanes 11 are provided around the intake port 3a that comes to the rear when the clamp 3 rotates. Therefore, the air in front of the clamp 3 in the rotational direction, that is, the air in the vicinity of the intake port 3a in the rotational direction of the clamp 3 is collected by the air introduction blades 11 as the clamp 3 rotates. As a result, the relative velocity between the air in the curved concave portion formed by the air introduction vanes 11 above the intake port 3a and the intake port 3a becomes small, and the intake amount of air to the intake port 3a is increased.

Since the air introducing blade 11 is provided with the inclined surface which is inclined forward in the rotation direction of the clamp 3, when the air introducing blade 11 rotates integrally with the clamp 3, the intake port 3
The air in the vicinity of “a” receives a downward force in the axial direction toward the intake port 3 a at the inclined surface of the air introduction blade 11. As a result, the intake amount from the intake port 3a increases. Further, the air inlet blade 11 surrounds the intake port 3a and an opening is provided in the front in the rotation direction. As a result, the pressure of the air in the vicinity of the intake port 3a increases due to the forward force in the rotational direction received from the air introduction blade 11 rotating integrally with the rotation of the clamp 3. Therefore, it is possible to prevent the air flow from leaking from the end portion of the air introduction blade 11 to the outer peripheral side, and increase the inflow amount of the air into the intake port 3a.

The circulating air flow, which is about to flow into the intake port 3a from the front side in the rotation direction of the air introducing blade 11, opposes the centrifugal force generated by the rotation of the clamp 3 from the outer peripheral side to the inner peripheral side of the clamp 3. It is a flow to be sent to.
By providing the blade 11 with the extension portion 11b that is inclined with respect to the surface of the clamp 3 in front of the rotation direction, the extension portion 11
The air in the front of the rotation direction of b is captured and guided by the extension portion 11b as the clamp 3 rotates. In this way, the suction amount is increased by receiving the force directed to the intake port 3a on the inner peripheral side of the curved recess.

As described above, the air introduction blade 11 has the effect of increasing the flow rate of the circulating air flow. It should be noted that although the air introduction blade 11 is provided separately from the clamp 3 by welding or the like as an example, it goes without saying that it may be provided integrally with the clamp 3 by die casting or the like.

<< Embodiment 2 >> FIG. 3 shows a spindle hub 2 and a clamp 3 in a magnetic disk apparatus according to Embodiment 2 of the present invention.
FIG. 3 is a perspective view showing a flow path of a circulating air flow provided in FIG. In FIG. 3, the spindle hub 2 and the clamp 3 are drawn apart from each other in the axial direction, as compared with the assembled state in the magnetic disk device, for the sake of explanation.

As shown in FIG. 3, in the magnetic disk device of the second embodiment, the spindle hub 2 is provided with the disk insertion cylindrical portion 2b and the lower flange portion 2a from the upper surface facing the clamp 3.
Up to three flow paths 2c are provided. Each channel 2
The circumferential positions of c correspond to the three intake ports 3a of the clamp 3, respectively. As a result, the air flowing from the intake port 3a of the clamp 3 directly flows into the flow path 2c. On the top surface of the spindle hub 2 facing the bottom surface of the clamp 3, three horseshoe-shaped flow path forming members 12 are provided so as to surround the starting ends 2g of the three flow paths 2c. In the direction away from the axis of rotation of the flow path forming member 12, the starting end portion 2g of the spindle hub 2 from the intake port 3a is prevented so as not to interrupt the air flow that flows in from the intake port 3a toward the flow path 2c. The outer peripheral portion of the flow path 2c provided in the disc insertion cylindrical portion 2b is provided so as to open.

FIG. 4 is a partial cross-sectional view showing a flow path in the magnetic disk device of the second embodiment, showing a state in which the magnetic disk device is assembled. In FIG. 4, the intake port 3a
A thick solid line with an arrow indicates the air flow sucked in from, and the direction of the arrow indicates the traveling direction of the air flow. The shaft 9 is fixed to a base member such as the housing 43. The spindle hub 2 is rotatably supported by a bearing 8 so as to rotate around a rotation axis (axis) 91 which is the center line of the shaft 9. A spindle motor (SPM) 5 that rotationally drives the spindle hub 2 is attached to the housing 43. In FIG. 4, the flow path forming member 12 is provided on the top surface of the spindle hub 2 as shown in FIG.
One surface (lower surface) of the flow path forming member 12 is attached to the top surface of the spindle hub 2, and the other surface (upper surface) is attached to the clamp 3.
It is assembled by contacting the bottom surface of. That is, the flow path forming member 1
Reference numeral 2 surrounds the space connecting the intake port 3a of the clamp 3 and the starting end portion 2g of the flow path on the upper surface of the spindle hub 2 with no gap except for the outer peripheral side portion. The flow path forming member 12 is preferably formed of an elastic material such as urethane in order to prevent a gap from being formed between the top surface of the spindle hub 2 and the clamp 3.

The circulating air flow in the magnetic disk device of the second embodiment will be described with reference to FIG. Air introduction wing 1
The airflow efficiently sucked from the intake port 3a of the clamp 3 by 1 flows into the flow path 2c provided in the spindle hub 2 and goes to the exhaust port 2f via the flow path 2c of the flange portion 2a. Further, a part of the inflowing air flow passes through the flow path 7c provided in the spacer 7 and is discharged from the exhaust port 7f of the spacer. Here, the clamp 3 and the spindle hub 2 are SPM.
It is rotating by 5. Therefore, the air sucked from the intake port 3a between the clamp 3 and the spindle hub 2 also rotates, but there is a difference in speed between the rotation of the air and the rotation of the SPM 5. Therefore, a part of the air taken in from the intake port 3a is provided in the spindle hub 2 as shown in FIG.
The flow path c shown in (2) deviates from the starting end portion 2g and tries to proceed in the direction of entering the gap between the clamp 3 and the spindle hub 2. Even if the air flow leaks into this gap, it will be sucked into the flow path 2c eventually, but if it cannot flow directly into the flow path 2c from the intake port 3a, it becomes a load resistance to the circulation air flow and lowers the flow rate of the circulation air flow. Will be a factor. Therefore, in this embodiment, the flow path forming member 12 having a substantially horseshoe shape is interposed between the lower surface of the clamp 3 and the upper surface of the spindle hub 2.

By using the flow path forming member 12,
The air taken in through the air intake port 3a does not leak into the gap between the clamp 3 and the spindle hub 2, and the flow path 2 is directly in the shortest path.
can be made to flow into c. As a result, according to the magnetic disk device of the second embodiment, the resistance of the circulation of the circulating air flow due to the inability to directly flow into the flow path 2c from the intake port 3a is decreased, and the flow rate of the circulating air flow is increased.

<Third Embodiment> FIG. 5 is a perspective view showing a circulating air flow passage provided in a spindle hub 52 and a clamp 3 in a magnetic disk device according to a third embodiment of the present invention. Figure 5
In order to clearly show the inflow of the airflow from the intake port 3a, the clamp 3 used in the first embodiment is also shown, though it is not directly related to the characteristic portion in the third embodiment. Figure 5
For descriptive purposes, the clamp 3 and the spindle hub 52 are depicted with a greater distance in the axial direction than in the assembled state in the magnetic disk device. In FIG. 5, the air flow that is sucked in through the intake port 3a and flows into the flow path 52c1 is indicated by a dashed line with an arrow, and the arrow direction is the traveling direction of the air flow.
The rotation direction of the SPM 5 is shown by a broken line with an arrow in the figure.

In FIG. 5, in the magnetic disk device of the third embodiment, the disk insertion cylindrical portion 52 of the spindle hub 52 is shown.
The flow path 52c2 provided on the outer peripheral side surface of b is spirally twisted so that the air flow traveling downward from the intake port 3a of the clamp 3 is directed in the backward direction in the rotation of the SPM 5. Further, the flow path 52c1 from the starting end portion 52s provided on the top surface of the spindle hub 52 near the intake port 3a to the disc insertion cylindrical portion 52b is from the radial direction of the spindle hub 52 (indicated by a two-dot chain line). SP
It is inclined and extends in the outer peripheral direction so as to open rearward in the rotation direction of M 5 (indicated by a dashed arrow). Similarly, the flow path 52c3 to the exhaust port 52f provided in the flange portion 52a is SP from the radial direction of the spindle hub 52.
In the rotation direction of M 5, it is inclined so as to open rearward and extends in the outer peripheral direction.

FIG. 6 is a cross-sectional plan view showing an outlet portion to the outer periphery of the flow path in the spacer 7 provided between the magnetic disks as shown in FIG. 4 in the magnetic disk device of the third embodiment. Is. In FIG. 6, in order to clearly show the inflow of the air flow from the flow path 52c of the spindle hub 52, the spindle hub 52 and the flow path 52c are also shown. In FIG. 6, the air flow entering from the flow path 52c of the spindle hub 52 further flows into the flow path 7b of the spacer 7,
The air flow discharged to the exhaust port 7f is shown by a thick solid line with an arrow, and the arrow direction is the traveling direction of the air flow.
The rotation direction of the SPM 5 is shown by a broken line with an arrow in the figure. As shown in FIG. 6, in the magnetic disk device of the third embodiment, the flow path 7b provided in the spacer 7 reaches the outer peripheral surface while being inclined in the rearward direction when the SPM 5 rotates. Further, the exhaust port 7f of the spacer 7 in FIG. 6 is widened in the rearward direction in the rotation of the SPM 5 due to the sloped surface 7d, thereby increasing the opening area. Even if the width of the flow path 7b is wide, a large chamfer may be provided to enlarge only the opening.

The circulating air flow in the magnetic disk drive of the third embodiment will be described with reference to FIGS. 5 and 6. The air that has been efficiently sucked in from the intake port 3a of the clamp 3 by the air introduction vanes 11 flows into the vicinity of the flow path 52c1 of the starting end portion 52s of the top surface of the spindle hub 52. After that, the air passes through the flow passage 52c1 and moves in the outer peripheral direction, then passes through the flow passage 52c2 on the outer peripheral side surface of the disc insertion cylindrical portion 52b, passes through the flow passage 52c3 provided in the flange portion 52a, and the exhaust port 52f, or Flow path 7b of spacer 7 shown in FIG.
Through the exhaust port 7f.

The operation and effect of providing the magnetic disk device of the present invention shown in FIG. 1 with the flow path 52c having the structure shown in FIG. 5 will be described below. First, the advancing direction of the air sucked from the intake port 3a largely changes in the direction toward the outer periphery in the flow path 52c1. As the SPM 5 rotates, a centrifugal force acting on the air causes a force in the outer peripheral direction, that is, in the traveling direction. However, the velocity of the airflow just flowing from the intake port 3a in the rotation direction is lower than the rotation velocity of the SPM 5. Therefore, the air flowing out from the inside of the flow path 52c1 provided on the top surface of the spindle hub 52 in the direction away from the center (outer peripheral direction) by the centrifugal force is a flow that is inclined with respect to the radial direction that is behind the rotation direction. A force is applied from the side surface of the road to the outer peripheral direction due to the component in the vertical drag direction. The direction of this force coincides with the traveling direction of the air flow, and therefore becomes the thrust of the circulating air flow, which has the effect of increasing the flow rate.

The flow velocity of the air flowing from the flow path 52c1 provided on the top surface of the spindle hub 52 to the flow path 52c2 provided on the outer peripheral side surface of the disk insertion cylindrical portion 52b of the spindle hub 52 is determined by the rotation of the SPM 5. Is smaller than the speed of the outer circumference of the spindle 52. Therefore, the air in the flow path 52c2 provided in the disc insertion cylindrical portion 52b is
From the inclined side surface of the flow path, which is behind the SPM 5 in the rotation direction, a force in the axially downward direction is received by the component in the direction of the vertical drag force due to the rotation of the SPM 5. The direction of this force coincides with the traveling direction of the air flow, and therefore becomes the thrust of the circulating air flow, which has the effect of increasing the flow rate.

From the flow channel 52c2 provided in the disc insertion cylindrical portion 52b to the flow channel 5 provided in the flange portion 52a.
The air flowing into 2c3 also receives a force in the outer peripheral direction due to the vertical drag force from the side surface of the flow path 52c3. The traveling speed of the air here is the same as that of each of the flow paths 52c that have already passed.
Since it is accelerated at 1, 52c2, the speed of the air in the rotation direction is close to the rotation speed of SPM 5.
Or it is about the same. So in this case,
The force in the outer peripheral direction due to the component in the vertical drag direction that the air in the flow path 52d3 receives from the side surface of the flow path becomes smaller. The main action and effect of the inclination of the flow path 52c3 provided in the flange portion 52a is to increase the opening area of the exhaust port 52f. Note that only the opening may be widened by providing a chamfer on the exhaust port 52f. With the increase in the opening area of the exhaust port 52f, the exhaust force received by the air in the exhaust port 52f becomes larger, and the flow rate of the circulating air flow is increased.

Further, the SPM of the air outside the exhaust port 52f
Although not shown in FIG. 5, the traveling speed of the SPM 5 is smaller than that of the SPM 5 because the actuator 45 on the surface of the magnetic disk 1 becomes an obstacle. Therefore, if the flow path 52c3 is inclined forward in the rotation direction of the SPM 5 and extends in the outer peripheral direction, the S outside the exhaust port 52f is reduced.
The air pressure in front of the PM 5 in the direction of rotation increases,
The discharge force may weaken from the exhaust port 52f. However, when the flow path 52c3 is inclined backward in the rotation of the SPM 5 as in the present embodiment, the air pressure which is outside the exhaust port 52f in the rear of the rotation direction of the SPM 5 is low, and the discharge force is increased. This has the effect of increasing the flow rate of the circulating air flow. That is, the air flow flowing in the circumferential direction from the flow path 52c3 provided in the rotating flange portion is the air in the outer circumference that is rotating in the opposite direction to the rotation of the flange portion on the outer circumference of the flange portion when viewed relatively. It is pulled by the frictional resistance. Since the pulling direction is the inclination direction of the flow path 52c3, the air easily flows out.

The operation and effect of using the spacer 7 having the structure shown in FIG. 6 in the magnetic disk device of the present invention shown in FIG. 1 will be described below. Spindle hub 52
Of the air that has flowed into the spacer 7 due to the small acceleration in the flow path 52c of SPM 5 in the rotation direction of SPM 5.
If it is smaller than the rotation speed of
The air flowing into b is subjected to a force in the outer peripheral direction due to the vertical drag component from the flow path side face 7c. Since this force coincides with the traveling direction of the air flow here, it becomes a thrust of the circulating air flow, and has the effect of increasing the flow rate. However, the SPM 5 of the air flowing in from the flow path 52c of the spindle hub 52
This effect cannot be expected if the traveling speed in the direction of rotation due to is already accelerated to the same level as the rotational speed of SPM 5.

However, since the flow path 7b provided in the spacer 7 is inclined, the opening area of the exhaust port 7f increases. With the increase of the opening area of the exhaust port 7f, the exhaust force received by the air in the exhaust port 7f becomes larger, and the flow rate of the circulating air flow is increased. The traveling speed of the air outside the exhaust port 7f in the direction of rotation by the SPM 5 is
The actuator 45 on the surface of the magnetic disk 1 becomes an obstacle and is lower than the rotation speed of the SPM 5. As described above in the spindle hub 52c3, if the flow path 7b is S
When the PM 5 is inclined in the rotational direction and extends in the outer peripheral direction, the air pressure outside the exhaust port 7f, which is the front in the rotational direction of the SPM 5, is increased, and the exhaust force from the exhaust port 7f is weakened. Like the spacer 7 (FIG. 6) of the present embodiment, when the flow path 7b is inclined in the rearward direction and extends in the outer peripheral direction when the SPM 5 rotates, the direction of rotation by the SPM 5 outside the exhaust port 7f. The air pressure at the rear of the air flow is reduced, the discharge force is increased, and the flow rate of the circulating air flow is increased.

<< Fourth Embodiment >> FIG. 7 is a sectional side view showing a flow path in a magnetic disk device of a fourth embodiment. In FIG. 7, in order to clearly show the inflow of the airflow from the intake port 3a, the magnetic disk 1, the clamp 3, the spacer 7, and the housing 43 are also shown, although they are not directly related to the features of the fourth embodiment. Further, in FIG. 7, the flow path 6 is sucked through the intake port 3a.
2C, the airflow discharged from the exhaust port 62f of the spindle hub 62 and the exhaust port 7f of the spacer 7 is shown by a thick solid line, and the arrow direction is the traveling direction of the airflow. S
The spindle hub 62, which is rotationally driven by PM5,
A plurality of magnetic disks 1 for storing information recording are laminated and fixed at equal intervals via one sheet or a spacer 7.

As shown in FIG. 7, in the magnetic disk drive according to the fourth embodiment, the flow passage 62c provided in the solid portion of the disk insertion cylindrical portion 62b has a flow path 62c as the air flow in the spindle hub 62 advances in the axial direction. It is inclined so as to approach the outer peripheral direction.

The operation and effect of using the spindle hub 62 having the configuration shown in FIG. 7 in the magnetic disk drive using the central blowing method shown in FIG. 1 will be described below. First, the air flowing into the flow path 62c from the intake port 3a is
The centrifugal force acting on the air accompanying the rotation of the SPM 5 receives a force in the outer peripheral direction, and is pressed in the outer peripheral direction from the side surface of the flow path 62c. Further, the air in the flow path 62c receives an axial force due to the vertical drag component from the inclined flow path side surface. Here, since this direction coincides with the traveling direction of the air flow, it becomes a thrust of the circulating air flow and has the effect of increasing the flow rate.

<Embodiment 5> FIG. 8 is a perspective view showing a housing 53 in a magnetic disk device according to Embodiment 5 of the present invention.
In FIG. 8, the magnetic disk 1, the clamp 3, the spacer 7, and the screw 4 are also shown, although they are not directly related to the features of the fifth embodiment in order to clearly show the positional relationship facing the outer peripheral side surface of the magnetic disk 1. Further, for the sake of explanation, FIG. 8 shows the spindle hub 2, the magnetic disk 1, the spacer 7, the clamp 3, and the screw 4 in the axial distance apart from the assembled state in the magnetic disk device. The rotation direction of the SPM 5 is shown by a thick solid line with an arrow in the figure. In the magnetic disk device of the fifth embodiment, a plurality of inclined projections 53b are provided on the housing inner wall 53a facing the outer peripheral side surface of the magnetic disk 1. Each of the inclined convex portions 53b corresponds to the discharge port 2 of the spindle hub 2.
f and the discharge port 7f of the spacer 7 pass between the magnetic disk 1 and the suction port 3 of the clamp 3 along the inner wall of the housing 53.
The direction of travel of the air flow toward a toward the upper side is formed so as to be inclined in the rotation direction of the SPM 5.

FIG. 9 is a sectional side view showing the inner wall portion of the housing, which is a characteristic part of the magnetic disk drive of the fifth embodiment.
In FIG. 9, the region sandwiched by the wavy lines shows the portion of the housing inner wall 53a, and on both sides thereof, a sectional side view from the vicinity of the inner circumference to the outer circumference of the magnetic disk 1 is shown. In FIG. 9, the slanted convex portion 53b provided on the inner wall 53a of the housing is shown with a mesh to clearly show it. Further, in order to clearly show the inflow of the air flow from the intake port 3a, the magnetic disk 1, the clamp 3, the spacer 7, and the housing 53 are also shown, although they are not directly related to the features of the third embodiment. Further, in FIG. 9, the gas is sucked in through the intake port 3a, flows into the flow path 2c, and is discharged through the exhaust ports 2f, 7
The air flow discharged from f is indicated by a thick solid line, and the arrow direction indicates the traveling direction of the air flow. On the spindle hub 2 rotated by the SPM 5, a plurality of magnetic disks 1 for information recording and storage are laminated and fixed at equal intervals via one sheet or a spacer 7.

The operation and effect of providing the inclined convex portion 53b having the structure shown in FIGS. 8 and 9 on the inner wall 53a of the housing in the magnetic disk device using the central blowing method shown in FIG. 1 will be described below. . First, the air exhausted from the exhaust port 2f of the spindle hub 2 or the exhaust port 7f of the spacer 7 moves to the outer peripheral side of the magnetic disk 1, and from the outer peripheral side surface of the magnetic disk 1 along the inner wall 53a of the housing to the intake port 3a.
After moving in the axial direction toward, the magnetic disk 1 moves from the outer peripheral side to the inner peripheral side along the inner surface of the cover 42. Here, the air flow passes from the outer peripheral side surface of the magnetic disk 1 to the housing inner wall 53a.
The airflow is rotating at a high speed due to the rotation of the SPM 5 while moving in the axial direction toward the intake port 3a. In the partial annular region where the housing inner wall 53a faces and is close to the outer peripheral side surface of the magnetic disk 1, the airflow rotating at high speed generates an axial force due to the component in the vertical reaction force direction from the inclined convex portion 53b. receive. Here, this direction is the thrust of the circulating air flow because it matches the traveling direction of the air flow,
It has the effect of increasing the flow rate.

As the configuration of the fifth embodiment, the same action and effect can be obtained by providing a plurality of inclined concave portions instead of the above-mentioned plural inclined convex portions on the housing inner wall 53a facing the outer peripheral side surface of the magnetic disk 1. To be

<Embodiment 6> FIG. 10 is a perspective view showing the structure of the lower surface of a partial annular plate in a magnetic disk device according to Embodiment 6 of the present invention. In FIG. 10, the partial annular plate 13 attached to the lower surface of the cover 42 is used for the magnetic disk device 1
It shows a state of looking up from the side. The rotation direction of the SPM 5 when assembled as a magnetic disk device is shown by a solid line with an arrow in the figure. In the magnetic disk device of the sixth embodiment, a partial annular plate 13 is provided on the inner surface of the cover 42 at a portion facing the surface of the magnetic disk 1 on the side of the clamp 3 where the intake port 3a is provided. The partial annular plate 13 is fixed to the cover 42 via the viscoelastic member 14 at the mounting portion 13f on the outer periphery, and the bottom surface 13e on the lower side thereof is arranged to face the magnetic disk 1.

A plurality of openings 13g are provided between the bottom surface 13e of the partial annular plate 13 and the mounting portion 13f on the outer peripheral side. A plurality of openings 13a are provided between the inner bottom surface 13e of the partial annular plate 13 and the mounting portion 13f. Further, the partial annular plate 13 is provided in a fan shape having a wide angle while avoiding the rotation region of the actuator 45.
A slanting wall 13d is provided at the starting end portion 13b and the terminating end portion 13c of the No. 3 in the circumferential direction. The upper end of the slanted wall 13d is the cover 4
Connected to 2.

In the magnetic disk device using the central blowing method shown in FIG. 1, the partial annular plate 1 having the structure shown in FIG.
The operation and effect of using the cover 42 to which 3 is attached will be described with reference to FIG. FIG. 11 is a sectional side view showing a state of circulating air flow in a magnetic disk device according to a sixth embodiment of the present invention. In FIG. 11, the air flow that is sucked in through the intake port 3a of the clamp 3 and flows into the flow path 2c of the spindle hub 2 and is discharged through the exhaust port 2f of the spindle hub 2 or the exhaust port 7f of the spacer 7 is indicated by a thick solid line. It is shown, and the arrow direction is the traveling direction of the air flow.
A plurality of information recording / storing magnetic disks 1 are laminated and fixed at equal intervals via a spacer 7 on a spindle hub 2 which is rotationally driven by an SPM 5.

On the surface of the magnetic disk 1, an air flow moving in the outer peripheral direction is generated by the centrifugal force accompanying the rotation of the SPM 5. Between the magnetic disk 1 on the top surface side of the spindle hub 2 where the intake port 3a is present and the cover 42, an air flow directed toward the outer peripheral side by centrifugal force and pushed up from the outer peripheral side along a vertical wall on the inner surface of the housing. Inner surface (lower surface) of the cover 42
From the upper part on the outer peripheral side of the magnetic disk 1 to the intake port 3a
There is a return air flow towards. That is, in the upper part of the uppermost magnetic disk 1, two air flows whose traveling directions are opposite to each other are simultaneously generated between the inner peripheral portion and the outer peripheral portion. The partial annular plate 13 has a cover 42.
From the outer peripheral side of the magnetic disk 1 along the inner surface of the intake port 3a
It is a disk for forming a tunnel-shaped portion that guides an air flow toward the. As a result, the air flow 99 directed from the outer peripheral side of the magnetic disk 1 toward the intake port 3a and the air flow directed toward the outer peripheral side by the centrifugal force are divided into an upper portion and a lower portion of the partial annular plate 13. This division has the effect of eliminating the flow resistance due to the interference of air flows in opposite directions and increasing the flow rate of the circulating air flow.

Further, due to dimensional restrictions, the partial annular plate 13
Is provided in a fan shape by cutting out a part of the rotation area of the actuator 45. In this case, the high-speed rotating airflow due to the rotation of the SPM 5 also flows toward the circumferentially starting end portion 13b or the end portion 13c of the partial annular plate 13.
As shown in FIG. 10, a slanted wall 13d is provided on the circumferentially starting end portion 13b and the terminating end portion 13c of the partial annular plate 13. As a result, a high-speed rotating air flow due to the rotation of the SPM 5 causes the circumferential start point 13b of the partial annular plate 13 to move.
Alternatively, the cover 42 and the partial annular plate 1 at the terminal end 13c.
It will not flow into the space between 3 and. As a result, the flow of the circulating air flow from the outer peripheral side of the magnetic disk 1 toward the intake port 3a is prevented from being obstructed by the rotating air flow,
It has the effect of increasing the flow rate of the circulating air flow.

Further, the partial annular plate 13 is made to face the surface of the magnetic disk 1 to form a rotating air layer between the bottom surface 13e of the partial annular plate 13 and the surface of the magnetic disk 1, and the air layer is disturbed. Used as a dynamic vibration absorber due to fluctuating pressure when a flow occurs. In this action, the air in the gap between the magnetic disk 1 and the partial annular plate 13 acts as a spring, and the partial annular plate 1
The viscoelastic material 14 provided for attaching 3 to the cover 42 causes damping vibration corresponding to the vibration of the magnetic disk 1 to absorb the vibration energy of the magnetic disk 1. In this way, the effect of suppressing the vibration of the magnetic disk 1 is obtained. The partial annular plate 13 may be, for example, a squeeze plate whose surface facing the disk is a smooth surface to reduce the vibration of the magnetic disk due to the air viscosity resistance force corresponding to the vibration of the magnetic disk 1.

<Embodiment 7> FIG. 12 is a sectional side view showing a circulating air flow from the partial annular plate 13 to the air introduction portion 11 provided in the clamp 3 in the magnetic disk device of Embodiment 7 of the present invention. In FIG. 12, three magnetic disks 1 for recording and storing information are laminated and fixed at equal intervals via a spacer 7 on a spindle hub 2 rotated by an SPM 5. The partial annular plate 13 is attached to the inner surface (lower surface) of the cover 42 of the housing 43. Intake port 3 of clamp 3
a is sucked in from the a, flows into the flow passage 2c of the spindle hub 2, and is discharged from the exhaust port 2f of the spindle hub 2 or the spacer 7
The air flow discharged from the exhaust port 7f is shown by a thick solid line, and the arrow direction is the traveling direction of the air flow.

As described in the sixth embodiment, the partial annular plate 13
In the space between the cover 42 and the cover 42, an airflow is generated from the outer peripheral side of the magnetic disk 1 toward the intake port 3a. On the other hand, between the partial annular plate 13 and the magnetic disk 1, the air layer rotates as the magnetic disk 1 rotates by the SPM 5. Due to the centrifugal force based on the rotation, an air flow is generated from the inner circumference side to the outer circumference side of the magnetic disk 1.
In the magnetic disk device of the seventh embodiment, the opening 13a on the inner peripheral side of the partial annular plate 13 is located further on the inner peripheral side than the innermost peripheral portion of the air introducing blade 11 of the clamp 3 and the opening 13a is formed.
Is provided at a position where the distance from the intake port 3a in the axial direction (upper surface direction) is small.

In the magnetic disk device using the central blowing method shown in FIG. 1, the partial annular plate 1 having the structure shown in FIG.
The operation and effect of the cover 3 having the cover 3 will be described below. The air flow passing through the space between the partial annular plate 13 and the cover 42 and flowing out from the opening 13a on the inner peripheral side of the partial annular plate 13 is introduced into the intake port 3a by the air introduction blades 11 provided in the clamp 3. Is inhaled. On the other hand, in the vicinity of the clamp 3 and the air introduction blade 11, particularly in the vicinity of the outer circumference thereof, an air flow toward the outer circumference is also generated by the centrifugal force accompanying the rotation of the SPM 5. The air flow toward the outer peripheral side draws the air flow flowing out from the opening 13a on the inner peripheral side of the partial annular plate 13 toward the outer peripheral direction of the clamp, which hinders introduction and intake of the air flow into the intake port 3a. .
Therefore, as shown in FIG. 12, the opening 13a on the inner peripheral side of the partial annular plate 13 is arranged on the inner peripheral side from the innermost peripheral of the air introducing blade 11,
Moreover, it is provided at a position where the axial distance from the intake port 3a is small.
With this structure, the opening 13 on the inner peripheral side of the partial annular plate 13 is formed.
Most of the air flow that has flowed out of a is introduced into the intake port 3a by the air introduction vanes 11 and sucked in, thereby increasing the flow rate of the circulating air flow.

In the magnetic disk device of the seventh embodiment, as shown in FIG. 13, the air introducing member 21 formed in a wing shape in each of the embodiments up to FIG. 12 may be an air introducing portion 21 having a truncated cone shape. . That is, FIG. 13 is a perspective view of a clamp having an air introducing portion of a modified embodiment of the magnetic disk device according to the seventh embodiment of the present invention. Although the partial annular plate is not shown in FIG. 13, the opening 13 on the inner peripheral side of the partial annular plate is shown.
a is a truncated cone-shaped air introduction portion 2 provided in the clamp 3.
It is located within the range of the diameter of the opening circle of the first opening 21b. The airflow that has flowed into the opening 21b on the inner peripheral side is SPM.
The centrifugal force associated with the rotation of 5 causes a force in the outer peripheral direction to be pressed against the inner peripheral wall of the truncated cone-shaped air introducing portion 21. It is deflected in the direction and introduced into the intake port 3a, and has the effect of increasing the flow rate of the circulating air flow.

In the description of Embodiments 1 to 7, the number of magnetic disks is three, but the same applies to one or a plurality of magnetic disks. Further, although the example in which the intake port is provided in the clamp has been described, the intake port may be provided in the flange of the spindle hub. It goes without saying that the magnetic disk devices of Embodiments 1 to 7 can be used in combination.

[0065]

As described in detail in the above embodiments, according to the magnetic disk device of the present invention, 2.5 inch or 3.
Even in a 5-inch small-sized magnetic disk device, a large amount of air can be introduced into the intake port by using the clamp having the air introduction portion. Therefore, it is possible to generate a sufficient circulating air flow from the inner peripheral side portion to the outer peripheral side portion of the magnetic disk in the housing. With this circulating air flow, it is possible to suppress turbulence and vortices that are generated between a plurality of magnetic disks or between the clamp and the magnetic disk due to the high speed rotation of the magnetic disk. As a result, it is possible to reduce the air excitation force, which is a factor of the natural vibration of the spindle system, which is a problem in the conventional magnetic disk device, and reduce the vibration of the magnetic disk. As a result, it is possible to provide a magnetic disk device that is small in size and can achieve high-speed rotation and high recording density.

[Brief description of drawings]

FIG. 1 is a perspective view of a magnetic disk device common to an embodiment of the present invention.

FIG. 2 is a perspective view of a clamp 3 used in the magnetic disk device according to the first embodiment of the present invention.

FIG. 3 is a perspective view of a spindle hub in the magnetic disk device according to the second embodiment of the present invention.

FIG. 4 is a side sectional view showing a flow path of a circulating air flow in a magnetic disk device according to a second embodiment of the present invention.

FIG. 5 is a perspective view of a spindle hub in a magnetic disk device according to a third embodiment of the present invention.

FIG. 6 is a sectional plan view showing a flow path provided in a spacer in a magnetic disk device according to a third embodiment of the present invention.

FIG. 7 is a sectional side view showing a flow path of a circulating air flow in a magnetic disk device according to a fourth embodiment of the present invention.

FIG. 8 is a perspective view showing a configuration of a housing in a magnetic disk device according to a fifth embodiment of the present invention.

FIG. 9 is a sectional side view showing a flow path of a circulating air flow in a magnetic disk device according to a fifth embodiment of the present invention.

FIG. 10 is a perspective view of a cover having a partial annular plate attached thereto in a magnetic disk device according to a sixth embodiment of the present invention, as viewed from below.

FIG. 11 is a sectional side view showing a flow path of a circulating air flow in a magnetic disk device according to a sixth embodiment of the present invention.

FIG. 12 is a sectional side view showing a flow path of a circulating air flow in a magnetic disk device according to a seventh embodiment of the present invention.

FIG. 13 is a perspective view of a clamp 3 used in a magnetic disk device according to another embodiment of Example 7 of the present invention.

FIG. 14 is a perspective view showing a configuration widely used in a conventional magnetic disk device.

FIG. 15 is a cross-sectional side view showing the configuration of a center blow-off method for reducing the air excitation force in the conventional magnetic disk device.

[Explanation of symbols]

1 magnetic disk 2, 52, 62 Spindle hub 2a, 52a, 62a Flange part 2b, 52b, 62b Disc insertion cylinder 2c, 52c1, 52c2, 52c3, 62c Flow path 2d inner wall of channel 2f exhaust port 2g Flow path at the beginning 3 clamps 3a intake port 3b screw through hole 4 screws 5 SPM (spindle motor) 7 Spacer 7b channel 7c Channel side 7f exhaust port 8 bearings 9 central axis 11 Air introduction wing 11b extension part 12 flow path components 13 Partial annular plate 13a inner peripheral side opening 13b Start end 13c Terminal part 13d inclined wall 13e bottom 13f mounting part 13g Outer hole 14 Viscoelastic material 21 Cone trapezoidal air inlet 21a Inner wall 21b opening 41 magnetic head 42 cover 43, 53 housing 53a housing inner wall 53b Inclined convex part 44 Airtight member 45 actuator 45a Actuator rotation center axis 46 voice coil motor

Claims (21)

[Claims] 1. A magnetic disk for recording information, a spindle hub having a flange portion for mounting the magnetic disk, and a disk insertion cylindrical portion for inserting a center hole of the magnetic disk, the magnetic disk being the spindle. A clamp that rotatably fixes integrally with the hub, a bearing that rotatably supports the spindle hub around an axis of rotation that is fixed to the base member, and a spindle motor that drives the spindle hub to rotate. A housing for accommodating each of the above components in a hermetically sealed manner, and a flow path provided in the spindle hub is sucked into the housing through an intake port provided in the clamp as the spindle motor rotates. To generate a circulating air flow which is then discharged from the exhaust port provided in the spindle hub and then sucked into the intake port again. 2. The magnetic disk device according to claim 1, wherein an air introduction blade to the intake port is provided at a portion that is behind the intake port when the spindle motor rotates. 2. The magnetic disk device according to claim 1, wherein an upper portion of the air introduction blade is provided so as to be inclined forward in a rotation direction of the spindle motor. 3. The magnetic disk device according to claim 1, wherein the air introduction vane surrounds the periphery of a portion of the spindle motor that comes to the rear of the intake port when the spindle motor rotates. . 4. The magnetic device according to claim 1, wherein the air introduction blade is provided so as to open to the outer periphery of the clamp in the front of the spindle motor in the rotation direction. Disk device. 5. A magnetic disk for recording information, a spindle hub having a flange portion on which the magnetic disk is to be mounted, and a disk insertion cylindrical portion into which a center hole of the magnetic disk is to be inserted, the magnetic disk being the spindle. A clamp that rotatably fixes integrally with the hub, a bearing that rotatably supports the spindle hub around an axis of rotation that is fixed to the base member, and a spindle motor that drives the spindle hub to rotate. A housing for accommodating each of the above components in a hermetically sealed manner, and a flow path provided in the spindle hub is sucked into the housing through an intake port provided in the clamp as the spindle motor rotates. To generate a circulating air flow which is then discharged from the exhaust port provided in the spindle hub and then sucked into the intake port again. In the magnetic disk device, the air flow passage provided in the disk insertion cylindrical portion of the spindle hub is rotated by the spindle motor after traveling in a direction parallel to the axis of rotation of the circulating air flow. A magnetic disk device, wherein the magnetic disk device is provided so as to be inclined in the direction of. 6. The flow path to the outer peripheral side surface of the disk insertion cylindrical portion formed on the top surface of the spindle hub adjacent to the intake port is in a direction rearward of a radial direction in the rotation direction of the spindle motor. The magnetic disk drive according to claim 1, wherein the magnetic disk drive extends in the outer peripheral direction while being inclined. 7. A flow path to an exhaust port provided in a flange portion of the spindle hub extends in an outer peripheral direction while inclining in a direction rearward of a radial direction when the spindle motor rotates. The magnetic disk device according to claim 1, wherein 8. A magnetic disk for recording information, a spindle hub having a flange portion on which the magnetic disk is to be mounted, and a disk insertion cylindrical portion for inserting a center hole of the magnetic disk, the magnetic disk being the spindle. A clamp that rotatably fixes integrally with the hub, a bearing that rotatably supports the spindle hub with respect to a rotation axis (axis) that is fixed to the base member, a spindle motor that rotationally drives the spindle hub, A housing for hermetically accommodating each of the above components is provided, and the housing is inhaled from an intake port provided in the clamp as the spindle motor rotates and passes through a flow path provided in the spindle hub. A circulating air flow is generated, which is discharged from the exhaust port provided in the spindle hub and is again sucked into the intake port. In the magnetic disk device, the air flow passage provided in the solid portion of the disk insertion cylindrical portion of the spindle hub has an outer peripheral direction of the spindle hub as the circulating air flow advances in the passage. A magnetic disk device, wherein the magnetic disk device is provided so as to be inclined toward. 9. A magnetic disk device comprising a spacer provided with an exhaust port for providing a predetermined gap between a plurality of stacked magnetic disks, wherein a flow path to the exhaust port provided on an outer edge of the spacer is the spindle. 2. When the motor rotates, it extends in the outer peripheral direction while inclining in the rearward direction.
9. The magnetic disk device according to claim 8. 10. The magnetic disk device according to claim 9, wherein an opening area of the exhaust port is formed larger than a cross-sectional area of the flow path. 11. The magnetic disk device according to claim 10, wherein the opening of the exhaust port is formed to be wider in the rear direction than in the radial direction when the spindle motor rotates. 12. The magnetic disk device according to claim 1, wherein a wall that forms a part of a flow path is provided in a gap between the clamp and the top surface of the spindle hub. Magnetic disk device. 13. The magnetic disk drive according to claim 12, wherein the wall is made of an elastic material. 14. A magnetic disk for recording information, a spindle hub having a flange portion on which the magnetic disk is to be mounted, and a disk insertion cylindrical portion into which a center hole of the magnetic disk is to be inserted, the magnetic disk being the spindle. A clamp that rotatably fixes integrally with the hub, a bearing that rotatably supports the spindle hub with respect to a rotation axis (axis) that is fixed to the base member, a spindle motor that rotationally drives the spindle hub, A flow path for air that is provided in the spindle hub, having a housing that hermetically houses the above-mentioned components, and that is sucked from the intake port provided in the clamp as the spindle motor rotates in the housing. Through the exhaust port provided in the spindle hub, and then re-injected into the intake port to generate a circulating air flow. In the magnetic disk device thus configured, on the inner wall of the housing facing the outer peripheral side surface of the magnetic disk,
A plurality of rectifying convex portions for rectifying the circulating air flow flowing from the inner peripheral side of the magnetic disk to the outer peripheral side of the magnetic disk toward the air inlet along the inner wall of the housing are provided, and the central rectifying convex portions are provided. A magnetic disk device, wherein an upper part near the intake port is inclined with respect to a generatrix of an inner wall parallel to the axis so as to be delayed in rotation of the clamp. 15. A magnetic disk for recording information, a spindle hub having a flange portion on which the magnetic disk is to be mounted, and a disk insertion cylindrical portion for inserting a center hole of the magnetic disk, the magnetic disk being the spindle. A clamp that rotatably fixes integrally with the hub, a bearing that rotatably supports the spindle hub with respect to a rotation axis (axis) that is fixed to the base member, a spindle motor that rotationally drives the spindle hub, A flow path for air that is provided in the spindle hub, having a housing that hermetically houses the above-mentioned components, and that is sucked from the intake port provided in the clamp as the spindle motor rotates in the housing. Through the exhaust port provided in the spindle hub, and then re-injected into the intake port to generate a circulating air flow. In the magnetic disk device configured as described above, an air flow from the outer peripheral side of the magnetic disk toward the inlet of the clamp along the inner surface of the cover at a portion facing the surface of the uppermost magnetic disk on the inner surface of the cover that covers the housing. A magnetic disk drive characterized in that a lid-shaped partial annular plate for forming a tunnel for guiding the magnetic disk is provided. 16. The magnetic disk drive according to claim 15, wherein the partial annular plate has a function as a squeeze plate for the magnetic disk. 17. A predetermined narrow space is formed between the lower surface of the partial annular plate and the magnetic disk, and the narrow space constitutes a dynamic vibration absorber that absorbs vibration energy of the magnetic disk. The magnetic disk device according to claim 15. 18. The partial annular plate is provided in a disk shape in which a part of the actuator for rotating the magnetic head is cut out, and the partial annular plate is formed in a cut-out disk direction of rotation. 18. A wall for closing a space between the lid and the partial annular plate is provided at a starting end portion and a terminating end portion of the sheet.
The magnetic disk device according to any one of 1. 19. The method according to claim 15, wherein the opening on the inner peripheral side of the partial annular plate is located on the inner peripheral side of the outermost peripheral portion of the air introduction blade provided in the clamp.
The magnetic disk device according to any one of 1. 20. The axial distance from the inner peripheral side opening of the partial annular plate to the surface of the clamp is the axial distance from the axial end of the air introducing blade to the surface of the clamp ( 20. The magnetic disk drive according to claim 19, wherein the magnetic disk drive is formed to be smaller than the height of the blade. 21. A frustoconical shape in which an air introducing portion provided in the clamp covers an outer side of an outermost periphery of an intake port of the clamp and has an opening portion facing an opening portion on an inner peripheral side of the partial annular plate. It is formed, It is characterized by the above-mentioned.
21. The magnetic disk device according to claim 20.