JPS58143476A - Automatic center adjusting mechanism for disk - Google Patents

Abstract

PURPOSE:To make a high precision center adjustment of a disk by providing an array tool which is elastic in radius directions annularly and coaxially with a spindle where the disk is loaded, and then inserting a pressing part formed under a hub into the tool. CONSTITUTION:The disk 6 mounted coaxially on the spindle 3 is pressed by a leaf spring 9 and the disk 6 is fixed with the hub 1 set pivotally thereupon to allow those three bodies to rotate in one body. Then, the array tool 2 is fixed coaxially on the apindle 3 and after the disk 6 is mounted at the circumferential edges of the array tool 2, the array tool pressing part 4 under the hub 1 is intruded into the gap between the array tool 2 and spindle 3 to force plural array tool pieces of the array tool 2 to spread in radius directions with a specific load. Consequently, the disk 6 is moved coaxially with the spindle shaft 5 to adjust the center of the disk 6 precisely.

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention The present invention relates to a self-aligning mechanism suitable for discs, particularly video discs, digital optical discs, etc.

Prior art A conventional self-aligning method is disclosed in Japanese Patent Application Laid-Open No. 55-27408.
There is a method using a tapered bias on the spindle side as described in K, and this taper part and the inner edge part of the disk hole, but with this method, the alignment accuracy is greatly influenced by the precision of the disk edge part, resulting in high precision. The disadvantage is that self-aligning accuracy cannot be achieved. Another method is to perform self-alignment using only an elastic aligner attached to the spindle, as disclosed in Japanese Patent Application Laid-Open No. 55-159202, but this method does not provide sufficient radial load, resulting in high The disadvantage is that self-aligning accuracy cannot be achieved.

In this way, self-alignment with higher precision than before is required.

The reason why IHc was adopted was to improve the reliability and performance of the original disk device, and it was necessary to minimize the eccentricity of the disk as it would affect the density of tracks.

OBJECTS OF THE INVENTION An object of the present invention is to eliminate the above-mentioned conventional problems and to provide a highly accurate disk self-aligning mechanism.

The present invention is based on a mechanism in which a donut model disk is placed on a spindle, which is a disk drive unit, and then a hub is attached to the upper end of the spindle to mount and fix the disk. In such a mechanism, a member having elasticity in the radial direction (for example, an aligner shown in the embodiments described later) is annularly disposed on the spindle coaxially with the rotation axis of the spindle.

Further, a suppressing portion having a cam function is formed at the lower part of the hub. After placing the disk on the periphery of the elastic member, this is used for rough positioning, and in cooperation with this, the suppressing part of the front hub is pushed into the gap between the elastic member and the spindle body. The gist of the present invention is a self-aligning mechanism for a disk that smoothly transmits the applied load to the inner diameter edge of the disk via the elastic member and presses the inner diameter edge outward in the radial direction for alignment.

Examples of the invention and its effects An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of the disk self-aligning mechanism. The upper part of the spindle 3 is a part on which a disk 6 is placed coaxially with the spindle, and the lower part is a part to which a spindle motor shaft (not shown) is fastened. A disk 6 is attached to the spindle 5.
After placing the hub 1 on top of the spindle 3, the disk 6 is fixed to the spindle 3.

Disc vertical direction (i.e. spindle axis direction)
Fixing is performed by a disk fixing leaf spring 9, and fixing and alignment in the radial direction with respect to the spindle shaft are performed by the aligner pressing portion 4 and the aligner 2 of the hub 1 of the present invention. The hub 1 itself consists of a permanent magnet 7 buried in the upper part of the spindle 3 and the hub 1.
8. Soft iron with lower Vcm installed. It is fixed to the spindle 3 by.

The disk 6 mounted in the above manner is as follows.

It rotates integrally with the hub 1 and spindle 5 following the rotation of the spindle motor.

An elastic aligner 2 is fixed to the upper part of the spindle 3 coaxially with the spindle shaft 5. The alignment tool 2 is arranged in an annular shape so that its outer diameter is smaller than the inner diameter of the disk 6. One of the functions of the aligner 2 is to roughly position the disk 6 relative to the spindle@5. After placing the disk 6 on the periphery of the alignment tool 2, the hub 1 is mounted on the spindle 3. Therefore, the alignment tool pressing part 4 of the hub 1 is pushed into the gap between the alignment tool 2 and the spindle 5, and the alignment tool 2 is forcibly expanded in the radial direction, the inner diameter of the disk 6 is pushed, and the disk 6 is aligned coaxially with the spindle shaft 5. Since the aligner suppressor 4 forcibly applies a constant load, the disk 6 can be reliably moved coaxially with respect to the spindle shaft 5, allowing precise self-alignment.

Note that the outer and inner diameters of the alignment tool pressing portion 4 of the hub 1 and the outer diameter of the joint between the spindle 3 and the hub 1 must be finished to a precision, and pressure must be applied so that force is evenly applied to the alignment tool 2.

Next, the alignment tool 2 will be explained in detail. Since the alignment tool 2 is a component that smoothly transmits the load applied by the alignment tool pressing part 4 of the hub 1 to the disk 6 as an even load in the radial direction, it is a component that achieves this purpose and is an elastic body with a large amount of deformation. Any shape may be used, and any material may be used. What is shown in FIG. 2 is an embodiment of the alignment tool, in which at least the portion where the alignment tool pressing part 4 and the disk 6 come into contact is separated into several alignment tool pieces. In this case, the number of aligning pieces is at least three, and in consideration of mounting accuracy, it is desirable to have more than this, and usually about ten is sufficient. Further, some examples of the shapes of the alignment tool pieces are shown in FIG. +a+tt There are two bending points, the alignment tool pressing part 4 and the disc 6.
is in contact with the surface and has two elastic parts at the top and the base, L61 has 0 bending points and the elastic part is (same as 41, but
The contact with the alignment tool suppressing part 4 is a line, and K is unreliable in transmitting a sufficient load. (CI is a leaf spring itself with other parts glued to it, and the only elastic part is the base, but such parts can also be used.

Next, a method of fixing the alignment tool 2 will be explained. The one shown in FIG. 2 has a crown shape, and is fixed to the spindle with a ring material 10 as shown in FIG. Other methods include creating grooves in the spindle for embedding individual alignment tool pieces, embedding the alignment tool pieces, and then fixing them with a ring material.

Next, the hub 1 will be explained. The material of hub 1 is as follows:
Just press the spring (alignment tool), so you can use plastic,
There are no restrictions on the metal, as long as it has enough rigidity to press the spring. In the embodiment shown in FIG. 1, the alignment tool suppressing section 4 has a conical shape, but it may have any shape as long as it displaces the alignment tool 2 by a certain amount. The disk fixing plate spring 9 is used to maintain the disk 6 evenly at a required locking torque, and in this embodiment, a ring-shaped plate spring with a ring-shaped disk pressure contact portion fixed thereto is used. Alternatively, several rectangular leaf springs may be attached to the hub IK.

Effects of the Invention As described above, according to the present invention, alignment is achieved by forcibly expanding the elastic aligner of the spindle portion by the suppressing portion at the lower end of the hub, so that accurate centering can be achieved reliably. For example, JP-A-55-
The self-aligning method using only the spring load of the alignment tool, such as the 159202, requires a high-precision spring that applies a load in the radial direction. load is required through the disc)
In the present invention, this load is externally applied by the hub, so the load of the spring itself is not a problem, and the elasticity of the spring is used to smoothly transmit the load applied to the hub to the disk. sand.

In other words, the present invention has the advantage of reducing the limitations on the shape and material of the spring (for example, the alignment tool shown in the embodiment) and ensuring that sincerity can be performed.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a disk self-aligning mechanism showing an embodiment of the present invention, Fig. 2 is an external view of an example of an elastic body alignment tool, and Fig. 3 is an illustration of some examples of alignment tool pieces. FIG. 1... Hub 2... Aligner 5... Spindle 4... Aligner suppressor 5... Spindle shaft 6... Disc 7... Permanent magnet 8
...Soft iron (magnetic material) 9...Flat spring for disc fixing 10...Ring material agent Patent attorney Usui 1) Benefit7. qt f 1 Figure 2 Figure 3 (Kyu) (4) (C)

Claims (1)

[Claims] (t) A mechanism in which a donut disk-shaped disk (t) is attached and fixed to a driving spindle by a knob, the spindle having a member disposed concentrically with the rotation center of the spindle and having elasticity in the radial direction of the disk. and a self-aligning mechanism for a disk, characterized in that a suppressing portion for suppressing the elastic member in the radial direction is formed at a lower part of the knob.