JP2000215571A - Rotational drive device for disk - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a rotational drive device for a disk capable of reducing the cost and thinning the device by allowing to obtain the required alignment accuracy of the disk, even though the high grade working accuracy is not demanded of component parts. SOLUTION: This device is provided with a turntable 11 which is rotationally driven by a motor having a rotary shaft 8, a center ring 50 fixed to the rotary shaft 8 while forming a part of the turntable and fitted into a center hole of the disk 45, a disk-aligning member 40 consisting of the elastic body furnished with plural alignment parts 44 having the pressing force to the outside in the radial direction, and a boss member 59 for holding the disk-aligning member 40 in between the fixed center ring 50 on the rotary shaft 8 at a side opposite to the disk mounted side of the center ring 50. The disk-aligning member 40 is bent at the one position, so as to make the angle acute at the outside in the radial direction to form the alignment part 44.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a rotary drive device for various types of disks such as D-ROMs and DVDs, and more particularly to a structure of the disk alignment means.

[0002]

2. Description of the Related Art In various disk rotation driving devices,
The disc centering means is provided so that when the disc is placed on a hub that is driven to rotate by a motor, the center of rotation of the disc coincides with the center of rotation of the rotor of the motor. FIG. 7 shows an example of a conventional disk rotation drive device, which is disclosed in Japanese Patent Application Laid-Open No. 10-10613 filed by the present applicant.
No. 1 is described. In FIG.
The disk rotation driving device has a motor portion and a turntable 82 on which a disk is mounted by being rotationally driven by the motor. The motor includes a stator portion and a rotor 80 as is well known. The rotor 80 has a rotor case 83 with a cup face down. A boss formed integrally with the center of the turntable 82 is press-fitted into a hole formed at the center of a portion corresponding to the bottom of the cup of the rotor case 83, and the rotary shaft 81 passes through the center hole of the boss. Is press-fitted. The rotating shaft 81 is supported by an appropriate bearing, and the turntable 82 and the rotor case 83 that constitute the rotor 80 together with the rotating shaft 81 are rotatable.

[0003] The upper end of the rotating shaft 81 is a turntable 82.
A center ring 84 is slidably fitted on the upper end of the rotating shaft 81 along the rotating shaft 81, and a center cap 85 is fixed to the upper end of the rotating shaft 81. The lower part of the center ring 84 is located in a concave part formed on the upper surface side of the turntable 82. A coil spring 86 for urging the center ring 84 upward is disposed in the recess, and the center cap 85 restricts the elevation of the turntable 82 by this urging force at a predetermined position. The outer peripheral surface of the upper half part of the center ring 84 is a gentle inclined conical surface, the lower part is a steeply inclined conical surface, and the largest diameter portion following this is larger than the diameter of the center hole of the disc 45. It has a large diameter.

When the disk 45 is placed on the turntable 82, the center of the disk 45 is
Is shifted from the center of rotation, the edge of the center hole of the disk 45 hits the conical surface of the center ring 84 and pushes the center ring 84 down along the rotation shaft 81 against the urging force of the spring 86. Thereby, the storing force of the spring 86 is increased. The position of the disk 45 is shifted while the edge of the center hole of the disk 45 slides along the conical surface of the center ring 84 by the upward biasing force of the center ring 84 due to the stored force of the spring 86, and the disk 45 is placed on the turntable 82. , The center hole of the disk 45 is aligned with the conical surface of the center ring 84, and the position of the disk 45 is regulated such that the center of the disk 45 coincides with the rotation center of the turntable 82. This is called alignment. The disk 45 thus aligned is pressed against the turntable 82 from above by an appropriate clamper, and is rotated integrally with the rotor 80 of the motor.

[0005]

According to the conventional disk rotation driving device as shown in FIG. 7, there is an advantage that the disk alignment operation is performed smoothly. On the other hand, the accuracy of the outer peripheral surface of the center ring 84 and the eccentricity of the center of rotation directly affect the disk alignment accuracy, so that the processing accuracy of the center ring 84 is strictly required. Moreover,
Since the processing accuracy is strictly required over the entire circumference of the center ring 84, there is a problem that the cost is increased. Further, it is necessary to mount the center ring 84 movably in the vertical direction along the rotation shaft 81, and it is necessary to secure a space for moving the center ring 84, which is disadvantageous in reducing the thickness of the disk rotation drive device. there were.

Further, according to the conventional disk rotation driving device, it is necessary to smoothly move the center ring 84 along the rotation shaft 81, but the sliding performance of the center ring 84 with respect to the rotation shaft 81 is unstable. Center ring 84
May be stuck on the rotating shaft 81 (so-called “galling”) and may not move. Therefore, in the invention described in the above-mentioned publication, the sliding surface of the center ring 84 with respect to the rotating shaft 81 is provided with a predetermined surface roughness so that the center ring 84 does not stick to the rotating shaft 81 when sliding along the rotating shaft 81. It is set to. However, there is a problem in that the processing cost increases if the rotation shaft 81 is set to a predetermined surface roughness so that the center ring 84 does not cause so-called galling with respect to the rotation shaft 81. Alternatively, the center ring 8 may be moved so that the center ring 84 slides smoothly.
A lubricant (oil, fluorine agent, or the like) is interposed between the inner surface of the rotary shaft 81 and the rotating shaft 81, or a lubricating plating is applied to the inner surface of the center ring 84 or the outer circumferential surface of the rotating shaft 81. However, there is a drawback that the processing cost rises accordingly. In addition, in order to move the center ring 84 along the rotation shaft 81, it is necessary to provide a slight gap between the inner peripheral surface of the center ring 84 and the outer peripheral surface of the rotation shaft 81. In addition, there is a disadvantage that it is difficult to obtain the alignment accuracy of the disk.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and can provide a necessary disk alignment accuracy even if the processing accuracy of the component parts is not required to be high. Therefore, it is an object of the present invention to provide a disk rotation drive device that can reduce the cost and reduce the thickness.

[0008]

According to a first aspect of the present invention, there is provided a turntable which is driven to rotate by a motor having a rotating shaft, and a part of the turntable which is fixed to the rotating shaft and A center ring fitted into the center hole of the disc, a disc centering member made of an elastic body having a plurality of centering portions having a biasing force radially outward, and a side opposite to the center of the center ring on which the disc is mounted. And a boss member for holding the disk alignment member between the center ring and the center ring, wherein the disk alignment member is formed at one location so as to form an acute angle on the outside in the radial direction. It is characterized by being bent to form the above-mentioned alignment part.

According to a second aspect of the present invention, in the first aspect of the present invention, the disk centering member includes a disk-shaped base, an arm extending radially outward from an outer peripheral side of the base, The arm portion has a centering portion bent at an acute angle with respect to the arm portion, and the base portion is sandwiched between the center ring and the boss member. And

[0010] The invention according to claim 3 of the present application is characterized in that the disk centering member is configured to bend around a position in contact with the outer peripheral edge of the boss member.

According to a fourth aspect of the present invention, there is provided a turntable rotatably driven by a motor having a rotating shaft, a part of the turntable being fixed to the rotating shaft, and being provided in a center hole of a disk. A center ring to be fitted, a disk alignment member made of an elastic body having a plurality of alignment portions having a biasing force radially outward, and a disk mounting side of the center ring opposite to a disk mounting side,
A rotor case for holding the disk alignment member between the turntable and the turntable, wherein the disk alignment member is bent at one location so as to form an obtuse angle inward in the radial direction to form the alignment portion. It is characterized by having.

According to a fifth aspect of the present invention, in the fourth aspect, the disk alignment member includes a disk-shaped base, an arm extending radially inward from an inner peripheral side of the base, and An arm portion or a tip end side thereof has a centering portion bent so as to form an obtuse angle with respect to the base portion, and the base portion is sandwiched between the turntable and the rotor case. I do.

[0013] As in the sixth aspect of the present invention, it is preferable that the centering portion of the disk centering member is provided with a centering convex portion bulged by drawing.

The disk centering member may be formed of a leaf spring material as in the invention of claim 7 of the present invention, or may be formed of resin as in the invention of claim 8 of the present invention. Is also good.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a disk rotation drive device according to the present invention will be described below with reference to FIGS. In FIG. 1, a hole for press-fitting a bearing holder 3 is formed in a substrate 1 made of a metal plate such as iron.
Around this hole is formed a burring portion 2 which has been drawn and has a cylindrical shape rising upward. This burring part 2
The bearing holder 3 is pressed into the bearing holder 3.
A stopper 25 is previously fitted on the outer periphery of the stator core 5, and the stator core 5 is press-fitted from below. The bearing holder 3 is formed into a bottomed cylindrical shape by drawing a metal plate, and the outer periphery of the lower end portion is pressed into the burring portion 2 of the substrate 1 and fixed. Bearing holder 3
A small flange-shaped engaging portion 4 is formed on the outer peripheral side of the upper end portion, and the stopper 25 is prevented from falling off by the engaging portion 4. The center hole of the stator core 5 is pressed into the outer periphery of the bearing holder 3 and fixed. The stopper 25 will be described later in detail. Stator core 5
Is a laminated core composed of a plurality of core plates, has a plurality of salient poles radially, and a driving coil 6 is wound around each salient pole.

A thrust receiving plate 9 is disposed on the inner bottom of the bearing holder 3, and a radial bearing 7 is fitted on the inner periphery of the bearing holder 3, and the radial bearing 7 is held by the bearing holder 3. In this embodiment, the radial bearing 7 is a sintered oil-impregnated bearing, and the axial length of the radial bearing 7 is slightly shorter than the axial dimension of the inner circumferential side of the bearing holder 3. A rotary shaft 8 is inserted into the inner peripheral side of the radial bearing 7, and the rotary shaft 8 is supported by the radial bearing 7 so as to be rotatable around its central axis. The lower end of the rotating shaft 8 is connected to the thrust receiving plate 9.
, And a load in the thrust direction applied to the rotary shaft 8 in the thrust direction is supported by the thrust receiving plate 9. The radial bearing 7 is impregnated with a lubricating oil, and the space between the inner peripheral surface of the radial bearing 7 and the outer peripheral surface of the rotating shaft 8 is lubricated with the lubricating oil. Since the bearing holder 3 is formed in a cylindrical shape with a bottom and has a bag shape, lubricating oil is supplied to the bearing holder 3.
The structure is such that it can be prevented from flowing out of the device.

The upper end of the rotating shaft 8 extends upward from the upper ends of the radial bearing 7 and the bearing holder 3, and a boss member 17 is press-fitted into the upper end of the rotating shaft 8 and the disk is adjusted from above. The core member 40 is inserted, and the turntable 11 is further press-fitted thereon. Details of the disk alignment member 40 will be described later. The boss member 17 is made of a metal plate and has a cylindrical downward cylindrical portion around a center hole, and this cylindrical portion is press-fitted into the rotating shaft 8. A disk portion is provided at one end of the cylindrical portion, and cooperates with the turntable 11 to sandwich the disk alignment member 40. The turntable 11 is also made of a press-formed product of a metal plate and has a cylindrical upward burring portion 12 around a center hole.
2 is press-fitted into the rotating shaft 8.

The turntable 11 is raised so that a ring-shaped groove 13 having an open upper side is formed outside the burring portion 12, and furthermore, a conical portion 34 which is gradually lowered toward the outside. A raised cylindrical portion 35 and a horizontal portion 36 following the cylindrical portion 35 are formed. The conical portion 34 and the cylindrical portion 35 of the turntable 11 are formed to have a slightly smaller diameter than the center hole of the disk 45 and
The center ring 50 is inserted into the center hole of the motor 5 and driven to rotate by a motor. The center ring 50 has a rotating shaft 8 like the conventional example shown in FIG.
And is fixed integrally with the horizontal portion of the turntable 11 without sliding in the axial direction. Disk alignment member 4
Reference numeral 0 indicates that the inner base 47 is fixed by being sandwiched between the turntable 11 and the boss member 17 and rotates integrally with the turntable 11. The pad 16 is attached to the upper surface of the horizontal portion 36, and the disk 45 is mounted thereon.

FIG. 2 shows the details of the disk alignment member 40. As shown in FIGS. 2A, 2B, 2C, and 2D, the disc centering member 40 has arms 42 extending radially outward from three places around a ring-shaped base 47. Have. As shown in FIG. 2A, the outer diameter of the base portion 47 is formed to be slightly smaller than the outer diameter 17D of the boss member 17 indicated by a dotted line. The disk alignment member 40 is formed of an elastic body such as a leaf spring material or a resin, and each of the arms 42 can be bent when an external force is applied. In particular, in the case of a leaf spring material, it can be easily and inexpensively manufactured by pressing.

The outer peripheral side of the disk centering member 40, more specifically, the portion near the tip of each arm 42 rises in one direction toward the disk insertion / removal direction, that is, an acute angle with respect to the arm 42. The bent portion 43 is formed by being bent so as to form: Each of the bent portions 43 is formed with a centering convex portion 46 that is punched out from the inside to the outside in a partial cylindrical shape by drawing, and the centering portion 44 is formed by the bent portion 43 and the centering convex portion 46. Make up. These partial cylindrical alignment projections 46 are formed to be long in the disk insertion / removal direction, that is, in the vertical direction. In addition, if the alignment convex portion 46 is formed by drawing, no shearing surface or burrs are generated around the alignment convex portion 46, so that it is possible to prevent snagging at the time of loading / unloading the disk.

The center ring 50, which forms a part of the turntable 11, has a portion corresponding to each alignment portion 44 of the disk alignment member 40 cut out, and a lower half of each alignment portion 44. Slightly project from the outer peripheral surface of the cylindrical portion 35 of the center ring 50. Therefore, when the center hole of the disk 45 is fitted on the outer peripheral surface of the cylindrical portion 35, the disk 4
The edge of the center hole 5 slides on the lower half of each alignment part 44, and the alignment of the disk 45 is performed by each alignment part 44. When the edge of the center hole of the disk 45 is in sliding contact with the lower half of each alignment section 44, each of the arms 42 is connected to the boss member 1
7 is bent downward with a position P in contact with the outer peripheral edge of the support 7 as a fulcrum. If the accuracy of the outer diameter of the boss member 17 is increased, the amount of deflection based on the spring characteristics is stabilized, and the variation is reduced. On the inner peripheral side of the disc centering member 40, the leading edge 4
A plurality of protrusions 1 are formed in partial arcs along one arc, and the leading edge 41 of these protrusions fits on the outer periphery of the rotating shaft.

The disk 45 is mounted on the pad 16 with the disk 45 aligned as described above. A ring-shaped chucking magnet 14 is inserted and fixed in the groove 13. When the disc holder (not shown) descends with the disc 45 resting on the pad 16, the disc holder is attracted to the turntable 11 by magnetic attraction between the magnetic material of the disc holder and the magnet 14. , Disk 45
Is pressed toward the turntable 11. The disc holder is provided rotatably with the turntable 11, the rotor 10 of the motor including the rotating shaft 8, and the disc.

An upper end surface of a rotor case 20 forming a part of the rotor 10 is integrally fixed to the lower surface of the turntable 11 by welding or other appropriate means. The rotor case 20 has a shape such that the cup is turned upside down, and a portion corresponding to the bottom of the cup abuts and is fixed to the lower surface of the turntable 11. A cylindrical rotor magnet 21 is attached to the inner surface of the cylindrical peripheral wall of the rotor case 20. The rotor magnet 21 also forms part of the rotor 10 and is rotatable integrally with the rotor case 20. The inner peripheral surface of the rotor magnet 21 is the stator core 5
Opposing the outer peripheral surface with an appropriate gap. By controlling the energization of the driving coil 6 of each phase by switching in accordance with the rotational position of each magnetic pole of the rotor magnet 21, the rotor 10 and the disk are continuously connected by the magnetic attraction between the rotor magnet 21 and each salient pole. It is designed to be rotationally driven.

In the embodiment shown in FIG. 1, the rotating shaft 8 has a simple columnar shape, and comes out of the radial bearing 7 as it is. Therefore, means for preventing the rotor from coming off using the stopper 25 described above is provided. As shown in FIG. 3B, the stopper 25 has a C-shaped planar shape, that is, a shape as viewed from the axial direction of the motor. The spread angle (center angle) of the C-shaped stopper 25 is slightly larger than 180 °,
In the illustrated example, the angle is about 240 °. The stopper 25 is an integrally molded product of a material having elasticity such as resin.
It can be expanded and contracted by the application of external force. As shown in FIGS. 3A, 3B and 3C, the stopper 25 has an inner peripheral side of a planar C-shape attached to the outer peripheral portion of the bearing holder 3. The inner peripheral edge of the stopper 25 rises to form a jetty 28, and the upper end of the jetty 28 has the bearing holder 3 as described above.
The stopper 25 is prevented from coming off by abutting on the engaging portion 4. A hook 26 is formed on the outer peripheral side of the stopper 25. The hook portions 26 have a shape in which a part of the outer periphery of the stopper 25 is raised, and are formed at three positions in the circumferential direction of the stopper 25, that is, at both ends and the center of the C-shape. At the tip of each hook portion 26, a locking portion 27 protruding outward in the radial direction of the motor is formed, and the outer upper end portion of each locking portion 27 is an inclined surface 29 that descends radially outward. I have.

In FIG. 1, a center hole is formed in a portion corresponding to the bottom of the cup of the cup-shaped rotor case 20 and a step portion is formed outside the center hole along a concentric circle. Is located below the lower surface of the turntable 11 and faces the locking portion 27 below the locking portion 27 of the stopper 25 with a slight gap. Accordingly, when the rotor 10 including the rotor case 20 and the like tries to escape from the radial bearing 7 together with the rotating shaft 8, the edge 2 of the rotor case 20
2 comes into contact with the locking portion 27 and is locked, so that the rotor 10 is prevented from coming off.

In FIG. 1, a circuit board 30 is mounted and fixed on the upper surface of the board 1. An appropriate circuit pattern is formed on the circuit board 30, and appropriate circuit components, for example, a magnetic detection element 31 such as a Hall element for detecting an index or a rotation speed of the rotor 10 are mounted thereon.

Next, a brief description will be given of the procedure for assembling the small motor according to the above-described embodiment, in particular, the assembly of the rotor 10 to the stator. A radial bearing 7 is press-fitted into the bearing holder 3 on the inner peripheral side, and a stopper 2 is
Insert 5 Next, the center hole of the stator core 5 is press-fitted and fixed. Next, the outer periphery of the lower end of the bearing holder 3 is
Lightly press-fit into the burring portion 2. The light press-fitting is not a strong press-fitting, but a relatively weak press-fitting that can correct the relative positional relationship and mutual posture of the members.
Next, the rotor 1 integrated around the rotation shaft 8
0 is inserted into the center hole of the radial bearing 7. At this time, the edge portion 22 of the rotor case 20 hits the inclined surface 29 of the locking portion 27 of the stopper 25, and the hook portion 26 of the stopper 25 is bent radially inward against its elastic force. The part 22 goes down. When the edge 22 reaches the lower side than the locking portion 27, the hook portion 26 is restored by its elastic force, and the locking portion 27 advances above the edge 22 to prevent the rotor from slipping out as described above. Structure. The edge 22 of the rotor case 20 when the rotor 10 is assembled
The contact portion of the edge portion 22 of the rotor case 20 with the locking portion 27 is chamfered so that the hook portion 26 of the stopper 25 is easily bent.

The perpendicularity of the rotating shaft 8 to the surface of the substrate 1 needs to be adjusted accurately. In particular, a disk drive motor requires high accuracy. Therefore, at the time when one type of assembling is completed, the substrate 1 is mounted using an appropriate jig or the like.
The verticality of the rotating shaft 8 with respect to the surface is checked, and if the accuracy is not sufficient, the relative attitude is corrected at the lightly press-fitted portion between the substrate 1 and the bearing holder 3 to obtain the above verticality. In this state, the substrate 1 and the bearing holder 3 are finally fixed by means such as bonding or welding the light press-fitted portion.

When the disk 45 is mounted on the disk rotation drive device constructed as described above, the edge of the center hole of the disk 45 slides on the conical portion 34 of the center ring 50 forming a part of the turntable 11. It is guided to the cylindrical portion 35 while being guided by the conical portion 34. When the disc 45 rests on the pad 16 and the center hole of the disc 45 is fitted on the outer peripheral side of the circular head 35, the edge of the center hole of the disc 45 is The disc 4 is brought into contact with the lower half, and is biased to the outside of each alignment section 44 by the urging force.
5 is performed.

As described above, according to the above embodiment, the centering operation of the disk 45 is performed by the centering part 44 of the disk centering member 40 having the plurality of (three) centering parts 44 in the outer peripheral direction. Is performed, if the accuracy of each alignment unit 44 is accurately obtained, a highly accurate disk alignment operation is performed, and the accuracy of the centering is not required unlike the conventional disk rotation drive device. Therefore, a disk rotation drive device with high alignment accuracy can be obtained at low cost.

The center ring 50 in the above embodiment has a fixed position in the axial direction, and does not move in the axial direction unlike the conventional disk rotation driving device. Can be made thinner.

Further, the disk centering member 40 is fixed by sandwiching the base portion 47 thereof between the center ring 50 and the boss member 17, and the plurality of arm portions 42 are provided on the outer peripheral side.
Since the centering portion 44 is formed by bending to form an acute angle at a place, when the disk 45 is mounted, the fulcrum of the bending operation of each arm 42 of the disk centering member 40 is Since it is determined at the position P in contact with the outer peripheral edge and there is no variation in the bending fulcrum for each arm portion 42, a disk rotation drive device with high alignment accuracy can be obtained from this point as well.

The centering operation of the disk is performed by placing the lower edge of the center hole of the disk on the centering member while the disk is placed on the upper surface of the turntable or the pad on the upper surface of the turntable with reference to the lower surface of the disk. Done by However, in the case of a DVD disc, two discs are bonded together so that recording and reproduction can be performed from both sides, and the center hole may be slightly displaced at the time of bonding. In some cases, displacement of the center hole due to bonding causes deterioration of alignment accuracy. In this regard, according to the above-described embodiment of the present invention, even if the center hole is displaced due to the attachment of the disks, it is possible to avoid the deterioration of the alignment accuracy. This will be specifically described with reference to FIG.

In FIG. 4, each center hole 76 of a DVD disk 75 in which two disks are bonded together,
77 are slightly displaced from each other, and for a particular alignment portion 44,
A case is considered where the edge of the disk center hole 77 above the edge of the lower disk center hole 76 is slightly shifted toward the inner diameter side. Naturally, the edge of the disk center hole 76 below the edge of the upper disk center hole 77 is slightly displaced toward the inner diameter side on the opposite side of the specific disk alignment portion 44 with respect to the rotation center. ing. The centering convex portion 46 formed in the centering portion 44 of the disk centering member 40 is formed in a bent portion 43 in which the arm portion 42 is bent at an acute angle upward, and in the example shown in FIG. Since the centering convex portion 46 is inclined along the direction of displacement of the center holes 76 and 77 of the disk 75 with the lower surface of the disk 75 serving as the reference resting on the pad 16, the lower side serving as the reference The lower edge of the disk center hole 76 corresponds to the disk centering convex portion 46, and the centering of the reference lower disk is performed. On the other hand, on the side opposite to the specific centering projection 46, the edge of the lower disk center hole 76 is
7 is slightly displaced toward the inner diameter side from the edge of the lower disc center hole 76, so that the lower edge of the reference lower disc center hole 76 is
This means that the centering of the lower disk serving as a reference is accurately performed.

In many of the disk alignment mechanisms in the conventional disk rotation drive device, the alignment portion that contacts the edge of the disk center hole is a vertical surface or a surface that is nearly vertical.
When the bonded discs are placed on a turntable and the center holes of the upper and lower discs are misaligned due to the bonding, the center of the lower disc hits the center of the disc, There was a problem in that the edge of the hole hit and became uneven, and the alignment accuracy of the lower disk as a reference was deteriorated. In this regard, according to the embodiment of the present invention, since the outer peripheral side of the arm portion 42 is bent at one location so as to be at an acute angle with respect to the arm portion, the centering portion 44 is formed. Alignment part 4 securely at the edge of the hole
4 abuts, and such a conventional problem can be solved.

Next, another embodiment of the present invention shown in FIGS. 5 and 6 will be described. In this embodiment, the shape of the disk alignment member and the mounting structure thereof are different from those of the above-described embodiment, and other configurations are the same as those of the above-described embodiment. ,
The different components will be mainly described.

5 and 6, the disk alignment member 6
Reference numeral 0 denotes a disk-shaped base 57, a plurality of (three in the illustrated example) arms 53 extending radially inward from the inner peripheral side of the base 57, and each arm 53 is connected to the base 57. And a centering portion 54 formed by being bent to form an obtuse angle with respect to the centering portion 54. Note that the distal end side of each of the arms 53 may be bent so as to form an obtuse angle with respect to the base 57. The disk aligning member 60 is formed of a leaf spring material, and the aligning portion 54 has an aligning convex portion 56 bulged by drawing. However, the disk alignment member 60
May be formed of resin. Disc alignment member 60
When it is made of resin, it can be made by integral molding.

In FIG. 5, the burring portion of the boss member 17 is press-fitted into the rotating shaft 8 of the motor as in the previous embodiment, and the burring portion 12 formed at the center of the turntable 11 is press-fitted. I have. In the turntable 11, similarly to the above-described embodiment, a conical portion 34 and a cylindrical portion 35 are formed by drawing, and the conical portion 34 and the cylindrical portion 35 form a center ring 50. A rotor case 20 constituting the rotor 10 of the motor is fixed to the lower surface of the turntable 11, and a base 57 of the disk alignment member 60 is sandwiched between the turntable 11 and the rotor case 20.
Therefore, the disk alignment member 60 is fixed to the turntable 11 on the side opposite to the disk mounting side of the center ring 50.

The disk alignment member 60 is made of an elastic metal or resin, and the plurality of alignment portions 54 of the disk alignment member 60 have a biasing force directed radially outward. The center ring 50, which constitutes a part of the turntable 11, has a portion corresponding to each alignment portion 54 of the disk alignment member 60 cut away, and the alignment alignment protrusion 56 of each alignment portion 54 has a center. Cylindrical part 35 of ring 50
Slightly protrudes from the outer peripheral surface of the. Therefore, disk 4
When the center hole 5 is fitted on the outer peripheral surface of the cylindrical portion 35, the edge of the center hole of the disc 45
The disc 45 is centered by the respective centering portions 54.

According to the embodiment described above, the disc centering member 60 made of an elastic material is sandwiched between the turntable 11 and the rotor case 20, and a plurality of centering portions 54 are respectively provided on the radially inner side. Since the disc is bent at an obtuse angle at one location, and the centering operation of the disk is performed by each centering portion 54, errors due to bending can be minimized, and therefore, the accuracy of each centering portion 54 can be accurately set. This facilitates accurate disk alignment operation. As a result, a disk rotation drive device with high alignment accuracy can be obtained at low cost. Further, since the center ring 50 is fixed in the axial direction and the center ring does not move in the axial direction unlike the conventional disk rotation driving device, the thickness of the disk rotation driving device can be reduced. . In addition, the same effects as in the above embodiment can be obtained.

In the present invention, the number of arrangement positions of the disk alignment portion is not limited to three, but may be two or four.
There may be more than one location.

[0042]

According to the first aspect of the present invention, a disc centering member made of an elastic material is sandwiched between the turntable and the boss member, and a plurality of centering portions are provided at one position on the outside in the radial direction. Since the disc is aligned to form an acute angle, and the centering of the disc is performed by each centering section, errors due to bending can be minimized, and therefore, the accuracy of each centering section can be accurately set. This facilitates accurate disk alignment operation. As a result, a disk rotation drive device with high alignment accuracy can be obtained at low cost. In particular, even if a disc is formed by laminating two discs and the two discs have different center holes, the lower edge of the reference lower disc center hole is In the centering portion, the centering of the lower disk serving as a reference is performed, and the centering of the lower disk is accurately performed.

According to the second aspect of the present invention, a highly accurate disk alignment member can be formed with a relatively simple structure. According to the third aspect of the present invention, when the disk is loaded, the fulcrum of the bending operation of the disk alignment member is:
Since it is fixed at a position in contact with the outer peripheral edge of the boss member, and there is no variation in the bending fulcrum for each disk alignment member, a disk rotation drive device with high alignment accuracy can be obtained.

According to the fourth aspect of the present invention, a disc centering member made of an elastic material is sandwiched between the turntable and the rotor case, and a plurality of centering portions are formed at one point on the inner side in the radial direction thereof at an obtuse angle. Since the disk is aligned by each alignment part, the error due to bending can be minimized, and therefore the accuracy of each alignment part can be easily set accurately. Thus, a highly accurate disk alignment operation is performed. As a result, a disk rotation drive device with high alignment accuracy can be obtained at low cost. In particular, even if the disc is a disc in which two discs are bonded together and the disc center holes are displaced from each other, the lower edge of the reference lower disc center hole is aligned with the disc center. In this case, the centering of the lower disk serving as a reference is performed, and the centering of the lower disk is accurately performed.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a disk rotation drive device according to the present invention.

2 (a) is a plan view, FIG. 2 (b) is a front sectional view, FIG. 2 (c) is a plan sectional view of a centering portion, and FIG. 2 (d) shows a centering portion of the disk centering member in the embodiment. FIG.

3A is a side view, FIG. 3B is a plan view, and FIG. 3C is a front sectional view showing a stopper in the embodiment.

FIG. 4 is an enlarged front sectional view of a main part showing a disk alignment operation in the embodiment shown in FIG. 1;

FIG. 5 is a longitudinal sectional view showing another embodiment of the disk rotation drive device according to the present invention.

FIG. 6 is a perspective view showing a disk centering member in the embodiment shown in FIG. 5;

FIG. 7 is a longitudinal sectional view showing an example of a conventional disk rotation drive device.

[Explanation of symbols]

 3 Bearing Holder 5 Stator Core 7 Radial Bearing 8 Shaft 10 Rotor 11 Turntable 17 Boss Member 20 Rotor Case 21 Rotor Magnet 40 Disk Alignment Member 44 Alignment Part 45 Disk 50 Centering 58 Axis 59 Boss Member 60 Disk Alignment Member 65 Adjustment Core 75 Disc

Claims (8)

[Claims] 1. A turntable rotatably driven by a motor having a rotating shaft, a center ring which forms a part of the turntable and is fitted into a center hole of a disk, and a plurality of radially outwardly biasing forces. A disc centering member made of an elastic body having a centering portion, and the center ring fixed to the rotating shaft on a side opposite to the disc mounting side, and the disc centering member located between the center ring and the center ring. And a boss member for clamping the disk, wherein the disk centering member is bent at one location so as to form an acute angle on the outside in the radial direction to form the centering portion. 2. The disk alignment member according to claim 1, wherein the disk alignment member has a disk-shaped base, an arm extending radially outward from an outer peripheral side of the base, and a tip end of the arm forming an acute angle with respect to the arm. 2. The disk rotation drive device according to claim 1, further comprising a centering portion bent so as to form the base portion, wherein the base portion is sandwiched between the center ring and the boss member. 3. The disk rotation drive device according to claim 1, wherein the disk alignment member is configured to bend around a position in contact with an outer peripheral edge of the boss member. 4. A turntable rotatably driven by a motor having a rotating shaft, a center ring which forms a part of the turntable and is fitted into a center hole of a disc, and a plurality of radially outwardly biasing forces. A disk alignment member made of an elastic body having an alignment portion, and a rotor case that sandwiches the disk alignment member between the center ring and the turntable on a side opposite to the disk mounting side. The disk rotation driving device, wherein the disk alignment member is bent at one location so as to form an obtuse angle on the inner side in the radial direction to form the alignment portion. 5. The disk alignment member according to claim 1, wherein the disk centering member includes a disk-shaped base, an arm extending radially inward from an inner peripheral side of the base, and an arm or a tip end of the arm having an obtuse angle with respect to the base. 5. The disk rotation driving device according to claim 4, further comprising a centering portion bent so as to form the base, wherein the base is sandwiched between the turntable and the rotor case. 6. The alignment section according to claim 2, wherein said alignment section has an alignment convex section formed by swelling by drawing.
Or the disk rotation drive device according to 5. 7. The disk rotation drive device according to claim 1, wherein the disk alignment member is formed of a leaf spring material. 8. The disk rotation driving device according to claim 1, wherein the disk alignment member is formed of a resin.