JPH07249247A - Device for driving disk to rotate - Google Patents

Abstract

PURPOSE:To reduce sliding resistance between the center hub of a disk and a hub base and to eliminate an erroneous chucking by providing a projection part projecting in the axial direction on a driving pin and making the top surface of the projection part a curved surface. CONSTITUTION:This device is provided with a driving pin body 100 consisting of the driving pin 7 engaged with the driving pin engaging hole of the center hub 2 and an arm part 21 and a hold member 20 holding the driving pin body. The driving pin 7 is provided with the projection part 11 projecting in the axial direction, and the top surface of the projection part is made a curved surface. Thus, when the center hub 2 of the disk is placed on the hub base 5, the center hub 2 is abutted on the projection part 11 formed on the driving pin 7. Since the projection part 11 is made the curved surface, a contact area between the projection part and the center hub 2 is small, the sliding resistance between the projection part 11 and the central hub 2 is reduced. Further, since the projection part 11 is made the curved surface, no projection part 11 is caught in the engaging hole of the central hub 2, and the disk is chucked correctly on the hub base 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk rotation driving device, and more particularly to a disk chucking structure.

[0002]

2. Description of the Related Art For example, a rotary drive device for driving a magnetic recording medium such as a floppy disk is known as shown in FIG. In FIG. 21, a hole is formed substantially in the center of the substrate 44, and the thrust bearing 4 is formed in this hole.
8 is attached. The thrust bearing 48 projects downward, and the projecting portion is fitted in the hole of the substrate 44. A cylindrical bearing holder 47 is mounted on the substrate 44 so as to surround the outer circumference of the thrust bearing 48. The bearing holder 47 has a flange 47 at the lower end.
a and the spacer 4 is provided outside the flange 47a.
5 is attached. The stator core 51 is placed on the upper surfaces of the flange 47 a and the spacer 45. The stator core 51 is configured by laminating a plurality of core bodies, and a plurality of salient poles are formed on the outer circumference. A coil 46 is wound around a plurality of salient poles of the stator core 51.

A cylindrical bearing 49 is attached to the inner peripheral surface of the bearing holder 47, and the rotary shaft 34 is inserted in the center hole of the bearing 49. The lower end of the rotary shaft 34 contacts the thrust bearing 48 and is supported in the thrust direction. The rotary shaft 34 is supported in the radial direction by bearings 49 and is rotatable.

A hub base 35, on which a disk is placed, is attached to the upper end of the rotary shaft 34. A cup-shaped rotor case 42 is fixed to the lower portion of the hub base 35 by a method such as caulking. The rotor case 42 covers the stator core 51 from the upper side, and the drive magnet 43 is attached to the inner surface of the peripheral wall. Drive magnet 43
The inner peripheral surface of is opposed to the salient poles of the stator core 51 with a constant gap. Therefore, the drive magnet 43 is energized by controlling the energization of the coil 46 wound around the salient pole, and the rotor case 42 and the hub base 35 are rotationally driven.

At the upper end surface of the rotor case 42, the hub base 35
The center hub 2 of the disc is attached to the outer peripheral side of the hub base 35.
A chucking magnet 36 for attracting the magnetic field is attached.

Next, a chucking structure of the above-described disk rotation driving device will be described. 21, FIG.
2, a hole 42a is formed in the upper end surface of the rotor case 42.
And a hole 42b is formed. A support member 41 is attached to the hole 42b from the side opposite to the chucking magnet 36, and one end of a partially arcuate arm portion 40 is attached to the support member 41. Arm 40
Can swing horizontally with the support member 41 as a fulcrum. The drive pin 37 is attached to the other end of the arm 40. The drive pin 37 attached to the arm 40 is inserted into the hole 42a, and the upper portion of the drive pin 37 projects upward from the hole 42a. The diameter dimension of the hole 42a is larger than the diameter dimension of the drive pin 37, and a gap is formed between the hole 42a and the drive pin 37, and the drive pin 37 can move within the range of this gap. ing. The drive pin 37 and the arm portion 40 form a drive pin body.

When a disk is mounted on the above magnetic disk drive, the rotary shaft 34 is fitted in the center hole 3 of the center hub 2 of the disk, and the drive pin 37 is attached to the end surface of the center hub 2 as shown in FIG. To abut,
The disc is tilted in one direction. When the rotating shaft 34 is driven in this state, the drive pin 37 slides on the end surface of the center hub 2 instead of the disk not rotating due to the contact pressure of the head (not shown). After this, the center hub 2
When the positions of the engaging hole 2a and the drive pin 37 coincide with each other, the drive pin 37 projects into the engaging hole 2a, and the disc becomes horizontal. Further, as the rotary shaft 34 is rotationally driven, the rotary shaft 34 is positioned in contact with part of the central hole 3 and the drive pin 37 with part of the engaging hole 2a, and chucking of the disk is completed.

The chucking structure of the type in which the drive pin 37 is swung by the arm portion 40 has been described above.
Another chucking structure is shown in FIG. In FIG. 24, a disk-shaped hub base 55 is attached to the upper end of the rotary shaft 54. A hole 55a is formed on the outer peripheral side of the hub base 55.

The base of the leaf spring 50 is attached to the surface of the hub base 55 opposite to the side on which the disk is placed, and the drive pin 57 is attached to one end of the leaf spring 50. . The drive pin 57 is arranged in the hole 55a, and the upper portion of the drive pin 57 projects from the hole 55a.

When the disk is placed on the chucking device as described above, the center hole 3 of the center hub 2 of the disk is placed.
The rotary shaft 54 is fitted in. As shown in FIG. 25, the surface of the hub base 55 is magnetized, whereby the end surface of the center hub 2 is attracted to the hub base 55 and the drive pin 57 is pressed by the end surface of the center hub 2. The leaf spring 50 is bent and the drive pin 57 is sunk in the hole 55a. When the hub base 55 rotates together with the rotating shaft 54 in such a state, the upper end portion of the drive pin 57 slides on the end surface of the center hub 2. When the rotary shaft 54 is further rotated, the positions of the drive pin 57 and the engagement hole 2a of the disc hub are aligned, the leaf spring 50 is restored, and the drive pin 57 is engaged with the engagement hole 2a.
fit in a. When the rotary shaft 54 is further rotated, the rotary shaft 5
4 is a part of the inner peripheral surface of the central hole 3, and the drive pin 57 is the engaging hole 2.
The chucking operation is completed by abutting on a part of the inner peripheral surface of a and positioning.

[0011]

There are two methods of chucking a magnetic disk drive device: a type in which the drive pin body swings in the horizontal direction and a type in which the drive pin body sinks downward. The drive pin body swing type shown in FIG. 21 needs to minimize the inclination of the center hub 2 when the center hub 2 of the disc rides on the drive pin 37.
Amount of protrusion from the hub base 35 (from the hub base 35 to the drive pin 3
It is not possible to increase the dimension up to the upper end of 7), and it is easy to cause a chucking mistake. Further, since the rotating shaft 34 is driven in a tilted posture of the disk until the drive pin 37 is inserted into the engagement hole 2a, the drive pin 37 and the center hub 2 come into contact with each other, causing friction and wear. Further, due to the abrasion and friction, the chucking position shifts and the like, which causes a recording / reproducing error of the disc.

Further, in the type in which the drive pin body is depressed as shown in FIG. 24, it is difficult to set the spring pressure of the leaf spring 50, the balance of the force due to the frictional force is easily lost, and a chucking error is likely to occur. There are drawbacks.

The present invention has been made to solve the above-mentioned problems, and provides a disk rotation drive device in which the sliding resistance between the center hub of the disk and the hub base is reduced to eliminate the chucking error. The purpose is to provide.

[0014]

The invention according to claim 1 is
A rotating shaft that fits in the center hole of the center hub of the disc,
A hub base that rotates integrally with the rotary shaft, a chucking magnet that is arranged around the hub base to attract the center hub with magnetic force, and a drive that engages with a drive pin engagement hole provided in the center hub. A rotary drive device for a disk, comprising a drive pin body having a pin and an arm portion, and a holding member for holding the drive pin body, wherein the drive pin is provided with a convex portion protruding in the axial direction. The top surface of the part is characterized by a curved surface. The invention according to claim 2 is characterized in that the convex portion is provided at a position eccentric to the outer peripheral direction from the center of the drive pin. The invention according to claim 3 is characterized in that the convex portion of a member different from the drive pin is planted in the drive pin, and the arm portion of the drive pin body is made of a spring material. It is characterized by being able to bend in the axial direction. According to a fifth aspect of the present invention, a rotary shaft fitted in the center hole of the center hub of the disk, a hub base that rotates integrally with the rotary shaft, and a center hub that is disposed around the hub base by magnetic attraction. Drive for rotating a disk including a chucking magnet, a drive pin body having a drive pin engaging with a drive pin engagement hole provided in the center hub, and an arm portion, and a holding member for holding the drive pin body. In the device, the drive pin is provided with a protrusion protruding in the axial direction, the hub base has a protrusion protruding from the disc-shaped base in the outer peripheral direction, and this protrusion is the arm of the drive pin body. The position of the center hub is regulated with the side surface of the drive pin abutting the positioning surface of the protrusion.

[0015]

When the center hub of the disk is placed on the hub base, the center hub comes into contact with the convex portion formed on the drive pin. Since the convex portion is a curved surface, the contact area between the convex portion and the center hub is small, and the sliding resistance between the convex portion and the center hub is reduced. Since the convex portion is a curved surface, the convex portion is not caught in the engaging hole of the center hub, and the disc is accurately chucked to the hub base.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A disk rotation drive device according to the present invention will be described below with reference to the drawings. The structure of the motor portion of the disk rotation driving device may be the same as that of a conventional motor, and therefore the description thereof will be omitted here, and the chucking structure of the disk will be mainly described. In FIGS. 1 and 2, a disk-shaped hub base 5 is attached to the upper end of a rotary shaft 4 rotatably supported by a bearing (not shown). A cup-shaped rotor case 10 is attached to the lower end surface of the hub base 5.
A hole 10a is formed in the ceiling portion of the rotor case 10 adjacent to the hub base 5.

A pin-shaped support member 20 is attached to a surface (a lower surface in FIG. 2) of the ceiling portion of the rotor case 10 opposite to the hub base 5, and the support member 20 has a partially arcuate arm portion. One end of 21 is attached. Arm 21
Can swing around the support member 20 as a fulcrum. A cylindrical drive pin 7 is attached to the other end of the arm 21. The drive pin 7 is inserted into the hole 10 a, and the upper portion thereof projects above the upper surface of the hub base 5. A convex portion 1 having a curved surface, more specifically, a shape obtained by cutting off a part of a spherical surface is provided on the top surface of the drive pin 7 on the protruding side.
1 is formed. The convex portion 11 is integrally molded with the drive pin 7 with resin, and is arranged at a position deviated from the center of the drive pin 7 toward the outer peripheral side of the rotor case 10. As described above, the arm 21 and the drive pin 7 constitute the drive pin body 100.

The diameter of the hole 10a is set to be larger than that of the drive pin 7, and a gap is formed between the drive pin 7 and the hole 10a. Therefore, the arm 21 swings around the support member 20 as a fulcrum, whereby the drive pin 7 can move in the hole 10a.

On the other hand, on the upper end surface of the rotor case 10, a chucking magnet 6 for attracting the center hub 2 of the disk to the hub base is arranged so as to surround the outer periphery of the hub base 5 and the drive pin 7 protruding from the hole 10a. It is installed.

Next, an operation example when a disk is placed on the chucking structure having the above-mentioned structure will be described. When the disc is placed on the hub base 5, as shown in FIG. 3, the center hole 3 of the center hub 2 of the disc
And the rotation shaft 4 engages with each other, and the protrusion 11 of the drive pin 7 protruding from the hole 10a abuts on the lower end surface of the center hub 2, so that the disc is tilted in one direction.

When the hub base 5 is rotationally driven together with the rotor case 10 and the rotary shaft 4 in this state, the drive pin 7 is also rotationally driven, but the disk mounted on the hub base 5 is a head not shown. It does not rotate due to contact pressure, and remains stationary. Therefore, the convex portion 11 of the drive pin 7 slides on the lower end surface of the center hub 2 while drawing an arc.

When the engaging hole 2a of the center hub 2 and the drive pin 7 are aligned with each other due to the sliding of the convex portion 11, as shown in FIG. 4, the drive pin 7 is fitted into the engaging hole 2a and the center hub 2 is engaged. The lower end surface of 2 contacts the upper end surface of the hub base 5, so that the disk is in a horizontal posture. Further, as the rotary shaft 4 rotates, a part of the outer circumference of the drive pin 7 contacts the side surface of the engagement hole 2a, and a part of the outer peripheral surface of the rotary shaft 4 contacts the side surface of the center hole 3, Is positioned on the hub base 5, and chucking is completed.

According to the chucking structure of the disk rotation driving device having the above-described structure, since the drive pin 7 is formed with the convex portion 11 having a curved surface, the contact area between the convex portion 11 and the center hub is increased. Becomes smaller, the sliding resistance between the center hub 2 of the disk and the drive pin 7 decreases, and the convex portion 11 has a curved surface, so that the convex portion 11 engages with the engaging hole of the center hub. Therefore, the drive pin 7 is surely engaged with the engagement hole. Therefore, it is possible to prevent chucking mistakes and
It is possible to obtain stable chucking characteristics. Further, by integrally molding the convex portion 11 together with the drive pin 7 with resin, it is possible to reduce the frictional resistance between the convex portion 11 and the center hub 2, and thereby to perform a smoother chucking operation. You can Since the convex portion 11 is located closer to the outer peripheral side of the rotor case 10 than the center of the drive pin 7, it is possible to reduce the inclination of the disk when the center hub 2 rides on the convex portion 11.

In the above embodiment, the protrusion 11 is formed integrally with the drive pin 7, but the present invention is not limited to this. For example, the convex portion 11 and the drive pin 7 may be formed as separate bodies and formed of different materials. That is, the drive pin 7 may be made of a metal that does not easily wear, and the protrusion 11 may be made of a resin having a small wear coefficient.

Next, an example of another chucking structure of the disk rotation driving device will be described. In FIGS. 5 and 6, a rotor case 10 is attached to one end of the rotary shaft 4. A hub base 5 for mounting a disc on the upper side of the rotor case 10 is attached to the rotary shaft 4, and the lower end surface of the hub base 5 is in contact with the upper end surface of the rotor case 10. The hub base 5 has two protruding portions 5b protruding from the disk-shaped base portion in the outer peripheral direction of the rotor case 10,
5c is formed. A drive pin 7, which will be described later, is located between the protrusions 5b and 5c, and the side surface of the protrusion 5b on the drive pin 7 side is a surface for positioning the drive pin 7. Further, downward protrusions 5a and 5a are formed on the protrusions 5b and 5c, respectively.

On the upper end surface of the rotor case 10, a hub base 5 is attached.
Center hub 2 of the disc in a form that covers the outer circumference of
A chucking magnet 6 for adsorbing is attached.

A drive pin body 70 is attached to the upper end surface of the rotor case 10 below the two protruding portions 5b and 5c so as to extend over these protruding portions 5b and 5c. The drive pin body 70 is composed of a cylindrical drive pin 7 provided in the center and a plate-shaped arm portion 7a, and the drive pin 7 and the arm portion 7a are integrally formed. Both ends of the arm portion 7a are covered with the protruding portions 5b and 5c of the hub base 5. Circular holes 7b, 7b are formed on both sides of the arm portion 7a with the drive pin 7 at the center. The holes 7b, 7b are located directly below the downward projections 5a, 5a of the hub base 5, and the projections 5a, 5a are inserted into the holes 7b, 7b. The diameters of the holes 7b, 7b are larger than the diameters of the protrusions 5a, 5a,
There is a gap between the holes 7b, 7b and the protrusions 5a, 5a. Therefore, the drive pin 7 formed integrally with the arm portion 7a is
The hub base 5 can be freely moved by this gap.

By inserting the projections 5a and 5a into the holes 7b and 7b, the drive pin 7 is prevented from coming off from the hub base 5. On the other hand, the drive pin 7 is provided with a convex portion 11 made of resin and having a curved upper portion at a position deviated from the central axis thereof in the outer peripheral direction of the rotor case 10.
The base of the convex portion 11 is embedded in the drive pin 7, and only the curved upper portion projects from the upper end surface of the drive pin 7. Convex part 1
The upper part of the curved surface of 1 has a shape in which a part of a spherical surface is cut out, and a part of a spherical surface having a relatively large diameter is cut out to form a gentle curved surface, and the height of the protrusion is low. Has become.

Next, an operation example when a disk is placed in the chucking structure having the above-mentioned structure will be described. The center hub 2 of the disc for the hub base 5
6, the lower end surface of the center hub 2 comes into contact with the convex portion 11 of the drive pin 7 protruding above the hub base 5, so that the disc is in a tilted posture. When the rotary shaft 4 is driven in this state, the hub base 5 and the like integrated with the rotary shaft 4 are rotationally driven, and the drive pins 7 are also rotationally driven, but the disk is stationary due to the contact pressure of the head (not shown). Has become. Therefore, the convex portion 11 of the drive pin 7 slides on the lower end surface of the center hub 2.

When the engagement hole 2a of the center hub 2 and the drive pin 7 are aligned with each other due to the sliding of the convex portion 11, the drive pin 7 is fitted into the engagement hole 2a, and the lower end surface of the center hub 2 and the hub. The upper end surface of the table 5 abuts, and the disc is in a horizontal posture. Further, by rotating the rotary shaft 4, a part of the outer circumference of the drive pin 7 comes into contact with the side surface of the engagement hole 2a, and a part of the outer peripheral surface of the rotary shaft 4 comes into contact with the side surface of the central hole 3. , The disk is positioned on the hub base 5, and chucking is completed. At this time, a part of the outer periphery of the drive pin 7 and the protruding portion 5b of the hub base 5 are in contact with each other and locked.

According to the chucking structure of the disk rotation driving device as described above, since the drive pin 7 is formed with the curved convex portion 11, when the disk is placed on the hub base 5, the center hub is formed. It is possible to reduce the sliding resistance between the drive pin 7 and the drive pin 7, prevent chucking mistakes, and obtain stable chucking characteristics. In addition, the protrusion 5b is directly brought into contact with the drive pin 7 and locked,
Since the drive pin 7 is positioned in the circumferential direction, the structure for positioning the drive pin 7 is simpler than that of the conventional one. Therefore, the number of parts can be reduced, and the assembly which requires accuracy can be performed. Only the rotating shaft 4 and the hub base 5 are provided, and the drive pin body 70 only needs to fit the holes 7b, 7b and the projections 5a, 5a of the hub base 5 with a spatial margin, so that the assembly accuracy can be remarkably improved. It will be possible. The parts other than the rotary shaft 4 and the hub base 5 do not need to be highly accurate, so that the manufacturing cost can be reduced. Further, since the chucking structure can be formed by assembling from one side without arranging the components on the back side of the rotor case 10, it is possible to improve the productivity. Further, in the drive pin 7, the convex portion 11 is formed of a resin having good slidability, and the drive pin 7 is formed of a material having high wear resistance. It is possible to form the drive pin 7 having the dual function. As a result, it is possible to provide a disk rotation drive device in which recording / reproduction errors are dramatically eliminated. Of course, although the performance is slightly lowered, the drive pin 7 and the convex portion 11 may be integrally formed of the same material.

Next, another embodiment of another chucking structure will be described. The chucking structure of the disk shown in FIG. 7 is almost the same as the example of FIG. 5 described above, but the structure of the drive pin body 80 is different from the embodiment described above. The drive pin body 80 includes the disc-shaped drive pin 12 and the drive pin 12
It is composed of a spring material 13 attached to the lower part of the. The spring member 13 has two flat portions 1 spread like wings on both sides.
3a and 13a, and a protrusion 13c located between these two flat portions. Flat surface portion 13a, 13a
Are formed with circular holes 13b and 13b, respectively, and the projections 5a of the hub base 5 are provided in these holes 13b and 13b, respectively.
5a is inserted. The holes 13b and 13b have the protrusion 5
Since the diameter dimension is larger than the diameters a and 5a, a gap is formed between the protrusions 5a and 5a and the holes 13b and 13b. You can move around freely. Further, the holes 13b, 13b and the projections 5a, 5a are fitted to each other, so that the drive pin body is prevented from coming off from the hub base 5.

A space is formed between the protruding portion 13c and the rotor case 10, and this space serves as a space for the protruding portion 13c of the spring member 13 to bend in the axial direction and the drive pin 12 to sink. There is. The upper portion of the protruding portion 13c is flat, and the drive pin 12 is attached to this portion by insert molding or the like. On the top of the drive pin 12, a convex portion 12a integrally formed with the drive pin 12 is formed at a position deviated from the center to the outside. Convex 12
a is a curved surface in which a part of the spherical surface is cut off.

Next, an operation example when a disk is placed in the chucking structure having the above-mentioned structure will be described. First, as shown in FIG. 8, when a disk is placed on the hub base 5, a part of the center hub 2 comes into contact with the convex portion 12a of the drive pin 12, and the disk is in a tilted posture. Further, the center hub 2 is attracted by the chucking magnet 6 against the elastic force of the spring material 13,
The lower end surface of the center hub 2 and the upper end surface of the hub base 5 come into contact with each other, and the drive pin 12 sinks downward, so that the disk has a horizontal posture as shown in FIG.

The rotary shaft 4 with the drive pin 12 depressed
When the drive pin 12 is rotationally driven, the drive pin 12 is rotationally driven together with the hub base 5 and the like integrated with the rotary shaft 4, but the disk is stationary due to the contact pressure of the head (not shown). For this reason,
The convex portion 12 a of the drive pin 12 slides on the lower surface of the center hub 2.

Engagement hole 2a of center hub 2 and drive pin 1
When the positions of 2 coincide with each other, the elastic force of the spring member 13 causes the drive pin 12 to return to its original position and fit into the engagement hole 2a.
Further, by rotating the rotary shaft 4, the drive pin 12
While a part of the outer periphery of the abuts on the side surface of the engaging hole 2a,
A part of the outer peripheral surface of the rotating shaft 4 contacts the side surface of the central hole 3,
The disk is positioned on the hub base 5, and chucking is completed. At this time, a part of the outer periphery of the drive pin 12 and the protruding portion 5b of the hub base 5 are in contact with each other and locked.

Also in the chucking structure as described above, since the convex portion 12a having a curved surface is formed on the top surface of the drive pin 12, the sliding resistance between the center hub 2 of the disk and the drive pin 12 is reduced and the chucking structure is reduced. It is possible to prevent king miss and obtain stable chucking characteristics. Further, since the drive pin body is not supported on the surface of the rotor case 10 opposite to the hub base 5, that is, on the inner surface side of the rotor case 10, it suffices to assemble the components while stacking them in one direction.
It is possible to improve the assemblability and keep the cost low. Further, since the drive pin 12 can be sunk downward by the protruding portion 13c of the leaf spring 13 forming the arm, the drive pin 12 tilts when the disk is chucked, and a load is applied to a specific portion of the disk. Can be prevented from concentrating. Therefore, the load on the head of the disk can be reduced, and the sliding friction of the drive pin 12 on the center hub 2 can be stabilized. In addition, the same effects as those of the above-described embodiment are obtained.

As shown in FIG. 10, a portion of the rotor case 10 below the protruding portion 13c of the spring member 13 may be concave so as to secure a large space for the drive pin 12 to sink. By doing so, the load on the head of the disk can be reduced. 7 to 10
In the embodiment shown in (1), the drive pin 12 and the convex portion 12a are integrally formed, but they may be formed of different members.

Next, another embodiment of another chucking structure will be described. 11 to 14, a cup-shaped rotor case 10 is attached to the tip of the rotary shaft 4. A hub base 15 is attached to the rotating shaft 4 above the rotor case 10, and a lower end surface of the hub base 15 is in contact with an upper end surface of the rotor case 10. A protruding portion 15a having a partially increased diameter is formed on the outer peripheral portion of the hub base 15, and a downwardly extending elliptical protrusion 15b is formed at the center of the protruding portion 15a.

A drive pin body 90 is arranged on the rotor case 10 at a position adjacent to the hub base 15. The drive pin body 90 includes a partially arcuate arm portion 17b and a drive pin 17 formed at one end of the arm portion 17b. The arm portion 17b is covered with the protruding portion 15a. Arm 17
An oblong hole 17c is formed in b, and a projection 15b formed in the protruding portion 15a is inserted into the hole 17c. The area of the hole 17c is set to be slightly larger than the area of the projecting end surface of the projection 15b. Therefore, there is a gap between the protrusion 15b and the hole 17c,
The drive pin 17 integrated with the arm portion 17b can freely move along the upper surface of the rotor case 10 by the amount of this gap. Further, by inserting the protrusion 15b into the hole 17c, the drive pin body 90 is prevented from coming off the hub base 15. On the top surface of the drive pin 17, the drive pin 17
A curved convex portion 17a is formed at a position deviated from the center position toward the outer peripheral side of the rotor case. The convex portion 17 a is integrally formed with the drive pin 17.

On the upper end surface of the rotor case 10, the hub base 1
A chucking magnet 16 for attracting the center hub 2 of the disk onto the hub base 15 so as to surround the disk 5.
Is attached.

In the chucking structure of the disk rotation driving device described above, since the drive pin 17 is movable in the horizontal direction along the upper surface of the rotor case 10, it is different from the embodiment shown in FIG. Similarly, when the disc is placed on the hub base 15, the drive pin 17 causes the disc to tilt. When the rotary shaft 4 rotates and the positions of the drive pin 17 and the engagement hole 2a of the center hub 2 coincide with each other, the disc is placed horizontally on the hub base 15, the disc is positioned, and chucking is completed. At this time, a part of the outer periphery of the drive pin 17 and the protruding portion 15a of the hub base 15 contact and are locked.

According to the chucking structure of the disk rotation driving device as described above, since the convex portion 17a having a curved surface is formed on the top surface of the drive pin 17, the convex portion 17a allows the center hub 2 of the disc and the drive pin to be formed. The sliding resistance with respect to 17 can be reduced, a chucking mistake can be prevented, and a stable chucking characteristic can be obtained. Further, since the drive pin 17 is directly brought into contact with and locked to the projecting portion 15a of the hub base 15 for positioning, the structure for positioning the drive pin 17 is simpler than in the prior art, thus reducing the number of parts. be able to. Further, since the assembly that requires accuracy is only the rotary shaft 4 and the hub base 15,
Assembling accuracy can be significantly improved. The parts other than the rotary shaft 4 and the hub base 15 do not need to be highly accurate, so that the manufacturing cost can be reduced. Further, since no parts are arranged on the back side (inner surface side) of the rotor case 10, the chucking structure can be formed by assembling from one direction side, which also makes it possible to remarkably improve the productivity. In the present embodiment, the drive pin 17 and the convex portion 17a are integrally molded, but of course, they may be members different from each other.

Further, as another embodiment, as shown in FIG. 15, the drive pin 18 and the curved convex portion 18 of the drive pin body.
The a and the arm portion 18c may be integrally formed by pressing. Since the number of parts can be reduced, it is possible to further reduce the manufacturing cost.

As shown in FIG. 16, of the drive pin 19 and the arm portion 20 constituting the drive pin body, the arm portion 20 is formed with a protrusion 20a by press working and the hub base 5 is provided with a hole 5d. The drive pin body may be supported by forming them and fitting them together.
The drive pin 19 is integrally attached to the arm portion 20 by insert molding, press fitting or other appropriate means. Drive pin 19
Is formed by resin molding or the like, and a convex portion 19b having a curved surface is integrally formed on the top surface thereof.

Further, as shown in FIG. 17, the drive pin 2
Reference numeral 1 may be a cup-shaped member, and the convex portion 21 may be formed on the upper end portion of the peripheral wall. The convex portion 21a has a curved surface and is formed on the outer peripheral side of the rotor case with respect to the center of the drive pin 21.

Further, as shown in FIG. 18, the drive pin 23
It is also possible to form two curved convex portions 23a, 23a at the upper end of the above and reduce the sliding resistance of the center hub 2 and the drive pin 23 by these two convex portions 23a, 23a. Further, as shown in FIG. 19, the sliding resistance of the center hub 2 and the drive pin 24 may be reduced by an elliptical convex portion 24a formed on the upper end of the drive pin 24, or as shown in FIG. As described above, the sliding resistance of the center hub 2 and the drive pin 25 may be reduced by the partially arcuate convex portion 25a formed on the upper end of the drive pin 25. The cross section of the convex portion 25a is curved.

[0048]

According to the first aspect of the present invention, since the drive pin is provided with the convex portion projecting in the axial direction and the top surface of the convex portion is formed into a curved surface, the convex portion and the center hub of the disk are formed. The contact area can be reduced, the engaging hole of the center hub of the disk is not caught by the convex portion, and chucking mistakes can be eliminated and stable chucking characteristics can be obtained.

According to the second aspect of the present invention, if the convex portion is provided at a position eccentric from the center of the drive pin in the outer peripheral direction, the inclination of the disk when the center hub is placed on the drive pin can be reduced. it can.

When the convex portion is formed of a component different from the drive pin as in the third aspect of the present invention, the convex portion is formed of a material having good slidability and the drive pin is formed of a material having excellent wear resistance. Thus, a high-quality disc chucking structure can be obtained.

According to the fourth aspect of the present invention, if the arm portion of the drive pin body is made of a spring material, when the center hub of the disk rests on the drive pin, the arm portion is bent to keep the disk horizontal. You can

According to the fifth aspect of the present invention, the drive pin has the convex portion projecting in the axial direction, and the hub base has the projecting portion projecting from the disc-shaped base portion in the outer peripheral direction. Since the part covers the arm part of the drive pin body and the position of the center hub is regulated with the side surface of the drive pin in contact with the positioning surface of the protruding part, the sliding resistance between the center hub and the drive pin is reduced. It is possible to obtain a stable chucking characteristic by reducing the number, and the drive pin body and the hub base may be placed and assembled in an overlapping manner, which simplifies the structure for positioning the drive pin and, moreover, from one side. Since the chucking structure can be formed by assembling, it can contribute to the reduction of manufacturing cost.

[Brief description of drawings]

FIG. 1 is an enlarged plan view of an essential part showing an embodiment of a disk rotation drive device according to the present invention.

FIG. 2 is a sectional view of the same.

FIG. 3 is a cross-sectional view showing an example when a disc is placed on the disc rotation drive device.

FIG. 4 is a cross-sectional view showing an example when the disk is placed on the disk rotation driving device and chucking of the disk is completed.

5A and 5B show another embodiment of a disk rotation drive device according to the present invention, FIG. 5A is an enlarged plan view of an essential part, and FIG.

FIG. 6 is a cross-sectional view showing a state immediately after the disc is placed on the disc rotation driving device.

7A and 7B show still another embodiment of the disk rotation driving device according to the present invention, FIG. 7A is an enlarged plan view of a main portion, and FIG.
Is an enlarged sectional view of a main part.

FIG. 8 is a sectional view showing a state immediately after the disc is placed on the rotary drive device for the disc.

FIG. 9 is a cross-sectional view showing another state immediately after the disc is placed on the rotary drive device of the disc.

FIG. 10 is a cross-sectional view showing an example of a rotor case applicable to the disk rotation driving device of the above.

FIG. 11 is an enlarged plan view of an essential part showing still another embodiment of the disk rotation drive device according to the present invention.

FIG. 12 is a cross-sectional view of a main part of a disk rotation driving device of the above.

FIG. 13 is a cross-sectional view showing a configuration of a hub base and a drive pin body of the rotary drive device of the same disk.

FIG. 14 is a cross-sectional view showing a configuration of a hub base and a drive pin body of the rotary drive device for the disk.

FIG. 15 is a cross-sectional view showing still another modified example of the hub base and the drive pin body that can be applied to the rotary drive device for a disk according to the present invention.

FIG. 16 is a cross-sectional view showing still another modified example of the hub base and the drive pin body that can be applied to the rotation drive device for a disc according to the present invention.

FIG. 17 is a cross-sectional view showing still another modified example of the drive pin body applicable to the rotation drive device for a disc according to the present invention.

FIG. 18 is an enlarged plan view of an essential part showing still another modified example of the drive pin body applicable to the rotation drive device for a disk according to the present invention.

FIG. 19 is an enlarged plan view of an essential part showing still another modified example of the drive pin body applicable to the rotation drive device for a disk according to the present invention.

FIG. 20 is an enlarged plan view of an essential part showing still another modified example of the drive pin body applicable to the rotation drive device for a disk according to the present invention.

FIG. 21 is a sectional view showing an example of a conventional disk rotation drive device.

FIG. 22 is an exploded perspective view showing an example of a disk chucking structure of the disk rotation driving device.

FIG. 23 is a cross-sectional view showing an example when a disc is mounted on the disc rotation drive device.

FIG. 24 is a cross-sectional view showing another example of a conventional disk rotation drive device.

FIG. 25 is a cross-sectional view showing an example when the disc is mounted on the disc rotation driving device of the above.

[Explanation of symbols]

 2 Center hub 3 Center hole 4 Rotating shaft 5 Hub base 6 Chucking magnet 7 Drive pin 11 Convex portion 20 Supporting member 21 Arm portion 70 Drive pin body 80 Drive pin body 90 Drive pin body

Claims (5)

[Claims] 1. A rotary shaft fitted in a center hole of a center hub of a disk, and a hub base which rotates integrally with the rotary shaft,
A chucking magnet disposed around the hub base to attract the center hub by magnetic force, and a drive pin body having a drive pin and an arm portion that engage with a drive pin engagement hole provided in the center hub. A rotary drive for a disk comprising a holding member for holding the drive pin body, wherein the drive pin is provided with a convex portion projecting in the axial direction, and the top surface of the convex portion is a curved surface. A disk rotation drive device characterized in that 2. The convex portion is provided at a position eccentric from the center of the drive pin in the outer peripheral direction.
A rotational drive device for the disk described. 3. The rotary drive device for a disk according to claim 1, wherein a convex portion of a member different from the drive pin is implanted in the drive pin. 4. The disk rotation drive device according to claim 1, wherein the arm portion of the drive pin body is made of a spring material and is capable of bending in the axial direction. 5. A rotating shaft fitted in a center hole of a center hub of the disk, and a hub base which rotates integrally with the rotating shaft,
A chucking magnet disposed around the hub base to attract the center hub by magnetic force, and a drive pin body having a drive pin and an arm portion that engage with a drive pin engagement hole provided in the center hub. A drive device for a disk, comprising: a holding member for holding the drive pin body, wherein the drive pin is provided with a convex portion projecting in an axial direction, and the hub base is formed from a disc-shaped base portion to an outer periphery. Has a projecting portion projecting in the direction, and this projecting portion covers the arm portion of the drive pin body and regulates the position of the center hub with the side surface of the drive pin abutting the positioning surface of the projecting portion. A disk rotation drive device characterized by the above.