JPH04139675A - Chucking hub for disk - Google Patents

Abstract

PURPOSE:To prevent the deviation of the center of rotation of a disk by forming three or more contacting parts which protrude to the direction of a center and come into contact with the outer peripheral part of a shaft at the edge of the motor shaft insertion hole of a chucking hub. CONSTITUTION:A circular flange part 21 is fixed firmly on the upper surface of the central circular hole 23 of the magnetic disk 22, and integrates the hub 20 and the disk 22 into one body. A circular recessed part 24 is formed projectingly at the part of this flange part close to the center, and the motor shaft insertion hole 25 is formed at its central position. Three supporting parts 26 for rotating the disk 22 at the central position by coming into contact with the motor shaft 7 when the shaft 7 is inserted are provided at the edge of this hole 25. Besides, the supporting parts 26 project toward the central direction of the motor shaft 7 respectively, and have bent parts bent in parallel with axial direction of the shaft 7 and in addition, downward, and these parts come into contact with the shaft 7 so as to rotate the disk 22 at the center without causing distortion.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a hub for chucking disks such as magneto-optical disks and magnetic disks that can be used for recording and reproducing digital signals, etc. The present invention relates to a disk chucking hub that is fitted with a drive means to rotationally drive the disk without any inconvenience.

(Prior Art) FIG. 9 is a perspective view of a conventional magnetic disk cassette casing 1 seen from below, which is formed from an upper half 2 and a lower half 3, and inside this is a magnetic disk 4 shown in FIG. is stored.

The magnetic disk 4 is made of a thin disc-shaped polymer film, and a circular chucking hub (hereinafter simply referred to as the hub) 5 protruding downward is integrally formed in the center of the magnetic disk 4. A magnetic layer is uniformly formed on the back side of the outer periphery.

The magnetic disk 4 is housed with a hub 5 protruding downwardly fitted loosely into a circular hole 6 formed in the lower half.

FIG. 11 is a partial view of only the hub 5 seen from the back side, showing a motor shaft insertion hole 8 in the center into which the motor shaft 7 is inserted, and a drive bottle insertion hole in the outside into which the drive bottle 9 is inserted. 1
0 is formed respectively.

When the cassette cylinder 1 is attached to the device and the magnetic disk 4 is driven, the rotation of the motor shaft 7 simultaneously rotates the drive bin 9 connected to the motor shaft 7, and this drive bin 9 is driven. The magnetic disk 4 is rotated by locking the edge of the bottle insertion hole 10.
(See No. 38145).

Further, FIG. 12 shows another conventional hub 11 as shown in FIG.
This is a partial view seen from the back side similar to the figure. In this case, a circular motor shaft insertion hole 12 is bored in the center, and the entire periphery of the motor shaft insertion hole 12 is extended downward (in FIG. 12). A bent portion 13 is formed on the back side of the paper, and during driving, the motor shaft 7 is inserted into the motor shaft insertion hole 12, and the magnetic disk 4 is rotated by the drive of the motor shaft 7. There is.

(Problem to be Solved by the Invention) By the way, when driving the magnetic disk 4, in the case of the hub 5 shown in the first conventional example, the motor shaft insertion hole 8 and the drive bottle insertion hole 10 are provided with a device. Since the configuration is such that the corresponding members are inserted, it requires man-hours to provide the two holes 8 and 10 in the hub 5, and it is also necessary to provide the corresponding members on the device side, making it complicated and It required a lot of man-hours.

Further, in the hub 11 shown in the second conventional example, only one circular motor shaft insertion hole 12 needs to be formed, and the number of man-hours for drilling the hole is reduced compared to the hub 5 of the first conventional example. The corresponding mechanism on the device side can also be simplified, but when the magnetic disk 4 rotates, the motor shaft insertion hole 1
Since the rotation center point is determined by the entire circumference of the bent portion 13 formed on the edge of the hole 2, the bent portion 13
If the circular shape of the magnetic disk 4 is distorted, the center of rotation will shift, causing problems in the rotation of the magnetic disk 4.

When forming the bent portion 13 into a circular shape, it is necessary to make the center the same no matter which point on the periphery is taken, making the forming difficult.

Furthermore, in the configuration in which the entire circumference of the bent portion 13 of the motor shaft insertion hole 12 is brought into contact with the motor shaft 7, the motor shaft 7 and the bent portion 1! ! +
There is also a problem in that when tribute such as dust adheres to the inner wall of the magnetic disk 13, the center of rotation of the magnetic disk 4 shifts.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a disk chucking device that is configured to accurately and reliably center a magnetic disk during rotation. The purpose is to provide a hub.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a disk chucking hub having the following configurations (1) and (2).

That is, (1) It is fixed to the center hole of the disk housed in the cassette housing, and has a motor shaft insertion hole in the center that fits with the motor shaft of the device, and the disk is rotated by rotation of the motor shaft. In the hub for chucking a disk to be moved, at least three support portions are provided on the edge of the motor shaft insertion hole, protruding toward the center of the motor shaft and abutting the outer circumferential portion of the motor shaft. Features a disc chucking hub.

(2) In the disk chucking hub according to claim (1), the motor shaft is provided continuously along the entire circumference of the hole edge of the motor shaft insertion hole including the support portion, along the insertion direction of the disk into the motor shaft. A disc chucking hub characterized by having a bent portion parallel to the .

(Function) At least three abutting portions are provided on the edge of the motor shaft insertion hole of the chucking hub that protrude toward the center of the motor shaft and abut against the outer periphery of the motor shaft to prevent the rotational center of the disk from shifting. To prevent.

(Example) DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

Fig. 1 is a front view of the cassette housing housing a magnetic disk for recording and reproducing when the shutter is open, Fig. 2 is a front view of the shutter when it is open, and Fig. 3 is a back view of the cassette case when the shutter is open.
FIG. 4 shows a rear view of the shutter when it is opened.

In the same figure, when the cassette housing 15 is installed in the device, the shutter opening/closing lever 16 is positioned on the locking portion 18 of the shutter 17 and presses the locking portion 18 in the Y direction, causing the shutter 17 to close.
is slid against a spring member (not shown) to the position shown in FIGS. 2 and 4. As a result, the window 19 corresponding to the recording/reproducing head (not shown) on the device side is opened, and since the shutter 17 has an integral structure bent toward the back side, the window 19 is opened at the same time on the back side. The hub 20, which is the main part of the present invention, is exposed.

FIG. 5 is a back view of the hub 20, and FIG. 6 is a front view of the hub 20.
A state diagram in which the motor shaft 7 is imaginatively inserted in the -A sectional view is shown, and the hub 20, which is the main part of the present invention, will be explained below using this diagram.

Reference numeral 21 denotes a circular collar portion, which is fixed to the upper surface of the central circular hole 23 of the magnetic disk (disk) 22 to integrate the hub 2O and the magnetic disk 22.

A circular recess 24 is formed protruding from the center of the flange 21, and a tooth-shaped motor shaft insertion hole 25 is formed at the center of the recess 24.

When the motor shaft 7 is inserted into the hole edge of the motor shaft insertion hole 25, it comes into contact with the magnetic disk 22.
Support part 26.27.28 for rotating at the center position of 2
are provided at three locations at approximately equal intervals.

The support portions 26, 27, and 28 are bent portions 26a, 27a that project somewhat toward the center of the motor shaft 7, respectively, and are bent downward parallel to the axial direction of the motor shaft 7 in FIG.
, 28a, and these bent portions 26a, 27a, 28
a comes into contact with the motor shaft 7 and rotates the magnetic disk 22 at the center of the magnetic disk 22 without distortion.

Further, since the bent portions 25a, 27a, and 28a come into contact with the motor shaft 7 for a predetermined length in the axial direction, stable horizontal rotation can be performed accordingly.

When forming the support portions 26, 27.28, first the recess 24 is squeezed into the center of the flat plate using a circular plate, and then the bent portions 26a, 2 of the support portions 26.27.28 are formed.
A tooth-shaped motor shaft insertion hole 25 is punched in the center of the recess 24 in the unbent and extended state of 7a and 28a, and then a cylindrical rod having approximately the same diameter as the motor shaft 7 is inserted. The bent portions 26a, 27a, which are inserted into the motor shaft insertion hole 25 and are in an extended state due to the insertion force of the cylindrical rod at this time.
It is formed by bending 28a.

Therefore, these respective bent portions 26a, 27a.

The inner wall of 28a can coincide with the center of the cylindrical rod.

That is, this hub 20 is connected to the central circular hole 2 of the magnetic disk 22.
3, the bent portions 26a, 27a, 2
The center of the inner wall 8a is the center position of the magnetic disk 22.

When using the magnetic disk 22, the bent portions 26a, 2
The hub 20 is attached to a circular magnet plate 29 fixed to the motor shaft 7 with the inner walls of 7a and 28a guided by the outer circumference of the motor shaft 7.
The recess 24 is attracted and holds the magnetic disk 22,
The cassette housing 15 that accommodates this is firmly fixed and held on the apparatus side.

When the motor shaft insertion hole 25 is inserted into the motor shaft 7,
For example, even if dirt or dust is attached to the motor shaft 7, the parts other than the bent parts 26a, 27a, and 28a do not come into contact with the motor shaft 7, so the inner wall of the motor shaft insertion hole 25 and the outer periphery of the motor shaft 7 There is a gap between the two parts, and compared to the hub 11 disclosed in the second conventional example in which the entire inner circumferential wall of the motor shaft insertion hole 12 is in contact with the outer circumference of the motor shaft 7, dirt,
It is possible to drive dust into the gap and reduce the possibility of foreign matter entering the contact area.

When the magnetic disk 22 is firmly fixed to the magnet plate 29, the rotational force from the motor shaft 7 is transmitted to the hub 20,
The magnetic disk 22 will rotate around the center of the magnetic disk 22 without any inconvenience.

In addition, in this embodiment, the bending part 2 is provided on the support part 26, 27, 28.
6a, 27a, and 28a, but the thickness of the hub 20 is increased so that the tip of the support portion 26, 27; 2B that contacts the motor shaft 7 is formed parallel to the axial direction of the motor shaft 7. If the configuration is such that the horizontal rotation of the magnetic disk 22 is not hindered, the separately provided bending portions 26a, 27a
, 28a are not required.

7 and 8 are diagrams of the hub 30 according to the second embodiment, in which FIG. 7 is a back view, and FIG. The inserted state diagram is shown, and the same components as in the first embodiment described above are given the same reference numerals, and detailed explanations are omitted.

In the same figure, 31 is a motor shaft insertion hole, and a bent part 32 is formed on the edge of this hole, parallel to the motor shaft and bent downward (toward the back side of the page) in FIG. There is.

The bent portions 32 are formed continuously over the entire circumference of the tooth-shaped motor shaft insertion hole 31, and support portions 34.
35 and 36 are provided at three locations each.

When the magnetic disk 22 rotates, the support portions 34 and 35
．． 36 bending portions 32 abut against the motor shaft 7, and the magnetic disk 22 is rotated at the center without deviation of the rotation center position.

In forming the support portions 34, 35, and 36, a circular hole having a diameter smaller than the minimum diameter of the motor shaft insertion hole 31 is punched out, and then the motor shaft insertion hole 3 whose planar cross-sectional shape is shown in FIG.
A rod having substantially the same shape as 1 is inserted into the circular hole, and a supporting portion 34, 35, 36 protruding somewhat toward the center of the circular hole and a continuous bent portion 32 over the entire circumference are simultaneously formed.

Therefore, by forming the bent portion 32 continuously over the entire circumference of the hole edge of the motor shaft insertion hole 31, the bent portion can be made strong, and the hub is less prone to cracking and damage. can be provided.

Incidentally, in both of the above embodiments, the number of support portions is provided at three locations, but the number is not limited to this, and the number of support portions may be more than three.

However, if there are too many, the number of locations where the center points coincide will increase accordingly, and the above-mentioned effect will be weakened.

(Effects of the Invention) As already mentioned, according to the invention set forth in claim (1), the disc is fixed to the central hole of the disc housed in the cassette housing,
In a disk chucking hub that has a motor shaft insertion hole in the center that fits with the motor shaft of the device and rotates the disk by rotation of the motor shaft, the hole edge of the motor shaft insertion hole has a The disc chucking hub is characterized by having at least three support parts that protrude toward the center of the motor shaft and come into contact with the outer circumference of the motor shaft, so that the center of rotation can be positioned easily during molding. This can be done accurately and easily, and when the disk is rotated, the center of rotation of the disk does not shift and rotational distortion does not occur.

Also, since there is a gap between the motor shafts other than the support part, it is easy to drive dirt and dust into this gap, and it is difficult for dirt and dust to enter between the motor shaft and the support part and shift the center of rotation of the disk. .

Furthermore, according to the invention described in claim (2), claim (1)
In the disk chucking hub described above, a bent portion parallel to the motor shaft is provided continuously along the entire circumference of the hole edge of the motor shaft insertion hole including the support portion along the insertion direction of the disk into the motor shaft. Since the hub for chucking the disc is characterized by the fact that the supporting part is particularly strong, cracks do not occur in the supporting part even during molding and when the disc is attached to the motor shaft and rotated. Effects such as being able to provide a disk chucking hub that is difficult and reliable are achieved.

[Brief explanation of the drawing]

Fig. 1 is a front view of a cassette case employing the present invention when the shutter is closed, Fig. 2 is a front view when the shutter is open, Fig. 3 is a back view of the cassette case when the shutter is open, and Fig. 4 is a front view of the cassette case when the shutter is open. FIG. 5 is a back view of the hub according to the first practical example of the present invention, and FIG. FIG. 7 is a back view of A according to the second embodiment, FIG. 8 is a state diagram in which the motor shaft is imaginatively inserted into the front B-B sectional view of FIG. 7, and FIG. 9 is a diagram of the inserted state. 10 is a perspective view of a conventional magnetic disk cassette casing viewed from the back, FIG. 10 is a perspective view of a conventional magnetic disk, and FIGS. 11 and 12 are back views of a conventional chucking hub. 7...Motor shaft, 15...Cassette housing, 16...Shutter opening/closing lever 20.30...Hub, 21...Flame, 22...
Magnetic disk, 24... recess, 25.31... motor shaft insertion hole, 26.27.28.34.35.36... support part, 2
6a, 27a, 28a, 32... bending portions. Patent applicant Victor Japan Co., Ltd. Kato Hatsujo Co., Ltd.

Claims (2)

[Claims] (1) It is fixed to the center hole of the disk housed in the cassette housing, has a motor shaft insertion hole in the center that fits with the motor shaft of the device, and rotates the disk by rotation of the motor shaft. The disk chucking hub is characterized in that the edge of the motor shaft insertion hole is provided with at least three support portions that protrude toward the center of the motor shaft and abut against the outer circumference of the motor shaft. Hub for chucking discs. (2) In the disk chucking hub according to claim (1), the motor shaft is provided continuously along the entire circumference of the hole edge of the motor shaft insertion hole including the support portion along the insertion direction of the disk into the motor shaft. A disc chucking hub characterized by having a bent portion parallel to the .