JP3155710B2 - Disk chucking device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk chucking device applied to a disk drive for rotating a recording disk such as a floppy disk.

[0002]

2. Description of the Related Art For example, a disk chucking device constituted by a 3.5-inch floppy disk drive has a rotating shaft which fits into a central hole formed in a metal hub of a recording disk, and a rotating shaft which fits the rotating shaft. A turntable that rotates integrally and a drive pin that fits into a drive hole formed at a position offset from the center hole of the hub on the turntable are configured. A chucking magnet for magnetically attracting the hub is also provided on the turntable. Conventionally, the chucking magnet is formed by punching a rubber magnet rolled into a sheet into a ring shape by a press or the like, and is arranged on a turntable so as to surround a rotary shaft. Therefore, when the recording disk is mounted on the drive device and the rotating shaft is fitted into the center hole of the hub, the hub is attracted to the chucking magnet,
The drive pin will fit into the drive hole of the hub.

[0003]

However, in the conventional disk chucking device, even if the drive pin is located at a position overlapping the drive hole of the hub, the drive pin may not fit into the drive hole and the recording disk may run idle. There's a problem. When such idling occurs, the hub is riding on the drive pin, so that the hub and the chucking magnet come into contact with each other on the opposite side of the drive pin, and the chucking magnet is worn or deformed.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems, and a disk chucking device in which a drive pin is securely fitted in a drive hole of a hub as long as a rotary shaft is fitted in a center hole of the hub. Is to provide.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a rotating shaft which fits into a center hole formed in a metal hub of a recording disk, and a turn which rotates integrally with the rotating shaft. A disk comprising: a table; a drive pin that fits into a drive hole formed at a position offset from the center hole of the hub on the turntable; and a chucking magnet configured on the turntable and magnetically attracting the hub. In a chucking device, the chucking machine
As a gnet, circumferential shape with the same shape and magnetic force
Three arc-shaped magnet pieces arranged in opposite directions.
Two of the three magnet pieces are one
So that the end of the
And one other magnet piece is opposed to the rotation axis.
And the two magnets on the side opposite to the drive pins.
Be located closer to the rotation axis than the piece
Thereby, when the rotation axis is the center, the drive pin side
At the moment when the hub is attracted,
On the opposite side of the
Is also large.

In the present invention , the hub is magnetically attracted on the turntable side in consideration of the balance of the attraction force applied to the hub.
Same shape and magnetic force as chucking magnet
Three arc-shaped magnets arranged in the circumferential direction
Using two of the three magnet pieces
The cut piece has one end near the drive pin.
Place each so that it is located, and one other magnet
The piece is located on the side opposite to the drive pin with respect to the rotation axis.
Position closer to the rotation axis than the two magnet pieces
Magnet piece placed on the drive pin side
Is smaller than the magnet piece located on the opposite side of the drive pin.
It is located far from the rotation axis.

Therefore, when the rotation axis is centered,
Moment for sucking the hub on the drive pin side
Sucks the hub on the side opposite to the drive pin
Greater than moment. Therefore, the hub is always
Side of the hub, so that the axis of rotation is
As long as the recording disc rotates once,
The moving pin surely fits into the drive hole of the hub.

Also, as a chucking magnet,
Since a magnet piece with one shape and magnetic force was used,
After preparing the same magnet piece,
Simply by placing the piece in place, the suction force applied to the hub
Can be optimized.

[0009] Further, an arc-like shape in which three are arranged in the circumferential direction.
Since one magnet piece is used, one rubber magnet sheet
Multiple magnet pieces can be cut out of
Wear.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing a disk drive provided with a disk chucking device to which the present invention is applied.

As shown in FIG. 1, the disk drive 8
Is composed of a stator assembly 9, a rotor assembly 10, and a disk chucking device 1 formed on the upper surface of the rotor assembly 10. The stator assembly 9 includes a stator substrate 11, a thrust bearing 12 and a radial bearing 13 attached to the stator substrate 11, a core holder 14 attached to an outer peripheral surface of the radial bearing 13, and a stator core 15 held by the core holder 14. And a core winding 16 wound around the stator core 15. The rotor assembly 10 includes a rotating shaft 2 rotatably supported by a thrust bearing 12 and a radial bearing 13, and the rotating shaft 2.
The rotor case 17 includes a cup-shaped rotor case 17 concentrically fixed to the rotor case 17 and a rotor magnet 18 attached to the inner peripheral surface of the rotor case 17.

The rotor case 17 has a central portion on the upper end surface protruding upward. The surface of the protruding portion is a circular flat portion, and is used as a turntable 3 of the disc chucking device 1 described below.

FIG. 2A is a front view showing a disk chucking device according to the present invention, and FIG. 2B is a side view thereof.

As shown in these figures, a disc chucking apparatus 1 of the present invention comprises a rotating shaft 2, a turntable 3 fixed concentrically to the rotating shaft 2, an arc-shaped swing arm 5, and a turntable. And a chucking magnet 19 attached to the table 3. A central portion of the turntable 3 is a projection 4 concentric with the rotating shaft 2, and its surface is covered with a resin. The protrusion 4 is formed slightly higher than the height of the surface of the chucking magnet 19. The swing arm 5 is arranged outside the protrusion 4 so as to surround the outer periphery of the protrusion 4 by about 1/4. One end of the swing arm 5 is supported by a pin 7 attached to the turntable 3, and the other end has a drive pin 5a projecting in the axial direction. Since the swing arm 5 can rotate around the pin 7 within a small range, the drive pin 5a moves in a direction approaching and away from the rotation shaft 2.

The disk chucking device 1 thus configured holds the floppy disk inside the disk drive device 8 via a metal hub formed on the floppy disk. That is, although the illustration of the structure of the floppy disk is omitted, the rotating shaft 2 is fitted into the center hole formed in the metal hub, and in this state, the rotating shaft 2 is shifted from the center hole in the hub. The drive pin 5a located at the same radial position as the drive hole fits into the formed drive hole.

In the present invention, the chucking magnet 19 is used.
Are composed of three magnet pieces 19a, 19b, 19c having the same shape and the same magnetic force. The magnet pieces 19a, 19b, and 19c are formed in an arc shape, and the outer peripheral side and the inner peripheral side have the same curvature. The ends on both sides are parallel sides. Therefore, as shown in FIG. 3, the magnet pieces 19a, 19b, and 19c are cut into circular arcs having the same curvature while feeding a band-shaped rubber magnet 20 rolled into a sheet shape by a roller or the like with a constant width in the longitudinal direction. Can be manufactured. Therefore, all the cut out magnet pieces are used as chucking magnets 1
Since it can be used as the nine magnet pieces 19a, 19b, 19c, the rubber magnet 20 is not wasted.

The magnet piece 1 thus formed
As shown in FIG. 2A, 9a, 19b, and 19c are arranged so as to surround the rotation shaft 2 and the protrusion 4. Here, of the three magnet pieces, two magnet pieces 19a and 19b are pasted on the turntable 3 so that one end is located near the drive pin 5a outside the drive pin 5a. The remaining one
The two magnet pieces 19c are attached to the rotation shaft 2 on the side opposite to the drive pin 5a.

The positions of the magnet pieces 19a, 19b, 19c are set so as to satisfy the following conditions. That is, in FIG. 2B, the magnitude of the attraction force of the magnet pieces 19a and 19b on the drive pin 5a side and the distance from the attraction center position to the rotary shaft 2 are F1 and L1, respectively. Drive pin 5
Assuming that the magnitude of the attraction force of the magnet piece 19c on the side opposite to “a” and the distance from the attraction center position to the rotating shaft 2 are F2 and L2, respectively, F1, L1, F2, and L2 are represented by the following equation F1 × L1 and L2 are set so as to satisfy L1> F2 × L2.

The operation of holding the hub attached to the center of a recording disk such as a 3.5-inch floppy disk in the disk chucking apparatus 1 thus configured will be described with reference to FIG. 4 (a) to 4 (c)
Is an explanatory diagram showing the above operation. In these figures, a center hole 22a in which the rotating shaft 2 fits is formed in the center of the hub 22 of the recording disk, and a driving hole 22b in which the driving pin 5a fits is formed at a position shifted from the center hole 22a. Have been. The hub 22 is made of metal that can be attracted to magnetic force.

First, as shown in FIG. 4A, when the recording disk is mounted on the disk drive 8, the hub 22
Is set at a position where the center hole 22a and the rotating shaft 2 overlap.

Next, the rotation shaft 2 is inserted into the center hole 22a of the hub 22.
Fits. At this time, the hub 22 is attracted by the chucking magnet 19, and the drive pin 5a is fitted into the drive hole 22b.

However, immediately after the floppy disk is mounted, the drive hole 22b of the hub 22 and the drive pin 5a are not necessarily at the same angular position. In this case, FIG.
As shown in FIG.
9, but in a state in which the drive pin 5 a has been ridden.

Even in such a case, the chucking magnet 19 has the drive pin 5 when the rotation shaft 2 is centered.
On the side a, the hub 22 is sucked with a larger moment than on the opposite side.
It is in a state of being strongly drawn to the side.

Therefore, if the drive hole 22b of the hub 22 and the drive pin 5a overlap before the turntable 3 makes one rotation, the drive hole 22b of the hub 22 is driven as shown in FIG. The pin 5a always fits.

As described above, in the disk chucking apparatus 1 to which the present invention is applied, the magnet pieces 19a and 19b arranged on the drive pin 5a side are more distant from the rotating shaft 2 than the magnet piece 19c arranged on the opposite side. When viewed from the viewpoint, the moment at which the chucking magnet 19 attracts the hub 22 on the drive pin 5a side with respect to the rotation shaft 2 when the rotation shaft 2 is the center is determined by the chucking magnet 19 on the opposite side to the drive pin 5a. 22 is greater than the moment of suction. Therefore, the hub 22
Since it is in a state of being strongly drawn to the drive pin 5a side,
The drive pin 5a always fits into the drive hole 22b of the hub 22 until the turntable 3 makes one rotation, so that the hub 22 does not contact the magnet piece 19c. Therefore, the magnet piece 19c does not wear or deform.

The shape of the magnet piece is not limited to an arc shape, but may be any shape such as a rectangle, a trapezoid, a triangle, and a U-shape. Further, if the number of magnet pieces is two or more, as described with reference to FIG. 3, the sheet-like rubber magnet 20 can be formed into a shape that causes almost no waste.

In mounting each magnet piece on the turntable 3, a groove 21 for fitting the magnet pieces 19a, 19b, 19c is formed on the turntable 3 in advance as shown in FIG. Thus, the magnet pieces 19a, 19b, and 19c can be easily attached to predetermined positions.

[0029]

As described above, in the disk chucking device according to the present invention, taking into account the balance of the suction force applied to the hub, the moment at which the hub is sucked on the drive pin side when the rotation shaft is centered. Is larger than the moment of sucking the hub on the side opposite to the drive pin. Therefore, according to the present invention, the hub is always strongly drawn toward the drive pin, so that as long as the rotating shaft is fitted into the center hole of the hub, the drive pin is inserted into the drive hole of the hub during one rotation of the recording disk. Fits securely.

[Brief description of the drawings]

FIG. 1 shows a disk drive device to which a disk chucking device of the present invention is applied.

FIG. 2A is a front view of a disk chucking device according to the present invention, and FIG. 2B is a side view thereof.

FIG. 3 is an explanatory view showing a state in which a magnet piece used in the disc chucking device of the present invention is cut out from a belt-shaped rubber magnet sheet.

FIGS. 4A to 4C are explanatory diagrams showing an operation of holding the hub by the disk chucking device.

FIG. 5 shows a disc chucking device of the present invention.
It is explanatory drawing which shows the example which formed the groove | channel for positioning a magnet piece on a turntable.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Disc chucking device 2 Rotating shaft 3 Turntable 4 Projection 5 Swing arm 5a Drive pin 8 Disk drive 19 Chucking magnet 19a, 19b, 19c Magnet piece 22 Hub 22a Center hole 22b Drive hole

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-62-197953 (JP, A) JP-A-3-290681 (JP, A) JP-A-61-233464 (JP, A) JP-A-9-1979 35382 (JP, A) JP-A 1-1113856 (JP, U) JP-A 1-113855 (JP, U) JP-A 64-37943 (JP, U) (58) Fields surveyed (Int. ⁷ , DB name) G11B 17/028

Claims (1)

(57) [Claims] A rotating shaft that fits into a central hole formed in a metal hub of a recording disk; a turntable that rotates integrally with the rotating shaft; and a turntable that is offset from the central hole of the hub on the turntable. In a disc chucking device having a drive pin fitted into a drive hole formed at a position and a chucking magnet configured on the turntable and magnetically attracting the hub, the chucking magnet has the same shape and shape as the chucking magnet.
Three arc-shaped magnets arranged circumferentially with magnetic force
A net piece is provided, and two magnet pieces of the three magnet pieces are
So that one end is located near the drive pin.
And the other magnet piece is attached to the rotation axis.
On the opposite side to the drive pin,
Be located closer to the rotation axis than the cut piece.
With this configuration, the drive pin can be moved around the rotation axis.
The moment of sucking the hub on the side
At the moment of sucking the hub on the side opposite to the pin
Disk chucking device
Place.