JPH04289571A - Hub mechanism of disk - Google Patents

Abstract

PURPOSE:To reduce the weight of a hub mechanism and to decrease the load of a spindle motor by forming the peripheral part of this mechanism of a synthetic resin. CONSTITUTION:The hubs 4, 5 are formed to a disk shape and are constituted of arbor parts 41, 51 provided with holes 41a, 51a fitting to a revolving shaft 61 and molded parts 42, 52 around these parts. Both ends thereof are fixed. The arbor parts 41, 51 are formed of a magnetic material, such as iron and the molded parts 42, 52 are formed of plastic, such as PPS resin. The load of the spindle motor 6 is decreased in this way. Further, the holes 42a, 52a for chucking are preferably formed in the molded parts 42, 52, by which the working cost is reduced.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk hub mechanism that is fixed to the center of a disk, which is an information storage medium, and is chucked onto a turntable.

0002

2. Description of the Related Art In recent years, optical disk devices have been put into practical use in which an optical disk as a storage medium is housed in a cartridge, and the cartridge can be attached to and removed from a drive device at will.

[0003] When such a cartridge is installed in a drive device, the optical disc is chucked onto a turntable on the drive device side.

[0004] For this chucking, a hub mechanism is provided at the center of the optical disc. For example, as shown in FIG. 4, this hub mechanism is a disk made of a magnetic material such as iron, and has a hole 1 passing through the center and a hole 2 of a constant depth formed around the hole 1.

On the other hand, the turntable is fixed to the shaft of a spindle motor, and a magnet and one vertical pin are attached to the top surface of the turntable. When the cartridge is inserted into the drive device, the hub mechanism is attracted to the turntable side by the magnet, and the hole 1 is fitted to the shaft of the spindle motor, and the hole 2 is fitted to the pin, respectively. An optical disc is chucked onto a turntable.

[0006]

[Problems to be Solved by the Invention] As mentioned above, conventional hub mechanisms were made of heavy materials such as iron, which resulted in a large load on the spindle motor when rotating the optical disk, and a large current at startup. It was necessary.

[0007]Also, the hole 2 of the hub mechanism needs to be formed accurately at a predetermined position, but performing such processing on metal materials such as iron requires a lot of man-hours and increases the processing cost. .

[0008] Also, during the above-mentioned chucking, the pin moves as the turntable starts rotating, and when the pin reaches the position of one hole 2 of the hub mechanism, the two are fitted and chucked. However, a mechanical shock is applied during the fitting. In this case, since both the pin and the hub mechanism are made of metal, the impact is large, causing deterioration of the durability of the chucking mechanism such as the pin and its supporting member.

[0009] As described above, the conventional hub mechanism has the problems that the load on the spindle motor is large, the processing cost is high, and the durability of the chucking mechanism is low.

SUMMARY OF THE INVENTION An object of the present invention is to provide a disk hub mechanism that can improve the above problems, reduce the load on the spindle motor, reduce processing costs, and improve the durability of the chucking mechanism. shall be.

[0011]

[Means for Solving the Problems] To solve the problem, the present invention provides that the entire hub mechanism is formed into a disk shape, and has a hole in the center thereof that fits into the rotating shaft of the turntable. A core metal part made of a magnetic material is disposed, a disk is fixed to the outer edge part, and a mold part made of synthetic resin is fixed around the metal core part.

[0012] Also, in the mold part, a number of holes are formed adjacent to each other on the circumference at a constant radius from the center, into which chucking pins attached to the turntable are fitted.

[0013]

[Operation] The peripheral part of the hub mechanism is made of synthetic resin, so
The overall weight is reduced and the load on the spindle motor is reduced.

[0014] Furthermore, since a hole into which a chucking pin is fitted is formed in the synthetic resin molded part, machining is easy and machining costs are reduced.

Furthermore, when the hole and the pin fit together, since one of the holes is made of synthetic resin and a large number of holes are formed adjacent to each other, the spindle motor starts rotating and the speed does not increase much. Since the above-mentioned fitting is performed, the mechanical impact is reduced. This improves the durability of the chucking mechanism.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a partial cross-sectional view of a chucking mechanism of an optical disc device according to an embodiment of the present invention. In the figure, an optical disc 3 is an information storage medium housed in a cartridge (not shown). Hubs 4 and 5 are attached to each surface of the central perforation position. The hub 4 is disk-shaped as shown in FIG. 2, and has a cored metal part 41 formed in the center, a molded part 42 formed around it, and both are fixed together.

The core part 41 is made of a magnetic material such as iron, and has a hole 41a into which the shaft 61 of the spindle motor 6 is fitted.
is perforated. Further, three holes 41b are drilled around it, and a penetrating hole 41c is provided in the center of the three holes 41b.
are perforated in each.

The mold part 42 is made of, for example, PPS resin,
It is made of plastic such as liquid crystal polymer, and a number of adjacent holes 42a are formed on the circumference at a constant radius from the center.

[0020] The hub 5 is almost the same as the hub 4 described above,
It is composed of a core metal part 51 and a mold part 52. Also,
The core part 51 has a hole 51a in the center and a hole 51b around it.
are drilled respectively, and the mold part 52 has a large number of holes 52.
a is formed. A screw is formed on the inner surface of this hole 51b.

Then, the screw 7 is inserted into the hole 41c from the hub 4 side.
It is threaded through the hole 51b on the hub 5 side. Thereby, the hub 4 and the hub 5 are fixed with the optical disk 3 sandwiched therebetween.

The spindle motor 6 is provided in an optical disk drive device (not shown). A turntable 8 is fixed to the shaft 61. A recess 8a is formed in the upper surface of the turntable 8 around the shaft 61, and a magnet 81 is fixed inside the recess 8a. Further, a chucking pin 82 is inserted into a hole drilled in the edge of the turntable 8.

The lower part of the pin 82 is fixed to one end of a leaf spring 83, and the other end of the leaf spring 83 is fixed to the lower surface of the turntable 8 with a screw 84.

Assume that a cartridge (not shown) is inserted into the optical disc drive device with the above configuration. As a result, the hole 41a of the hub 4 or the hole 51a of the hub 5 is fitted with the shaft 61 of the spindle motor 6, and the hub 4 or 5 is attracted by the magnet 81. At this time, the hole 42a or 52a is located exactly at the pin 82.
If they match, the two will fit together. Further, if the position is shifted, the pin 82 is pushed down and the leaf spring 83 is bent.

After this, the spindle motor 6 is driven and the turntable 8 starts rotating. Now, hole 42a, 5
If 2a and the pin 82 were not fitted, the hubs 4 and 5 would start rotating slowly due to inertia, whereas the turntable 8 would start rotating earlier. As a result, the pin 82 slides on the lower surface of the hubs 4, 5 and fits into one of the holes 42a, 52a.

In this manner, the optical disc 3 is chucked onto the turntable 8 and rotated in a predetermined manner.

As described above, in this embodiment, the hubs 4, 5
is composed of iron core parts 41, 51 and synthetic resin mold parts 42, 52. As a result, the hub mechanism is lighter than the conventional hub mechanism, which was entirely made of iron, and the load on the spindle motor 6 is reduced.

[0028] Also, chucking holes 42a, 52a
are formed on the mold parts 42, 52 side. conventionally,
In contrast to drilling holes in a metal member one by one, in the mold parts 42 and 52 of this embodiment, a plurality of holes can be easily formed using a predetermined mold. This reduces processing costs.

By the way, in general, after the turntable starts rotating, a mechanical shock occurs when the chucking pin and the hole in the hub fit together, which shortens the life of the pin and its supporting members. .

In this embodiment, the chucking hole 4 is
2a and 52a are formed on the hub 4 or 5 made of synthetic resin. This reduces the impact compared to the conventional case where metals fit together, so the life of the chucking mechanism can be extended.

[0031] In general, when the turntable starts rotating, even if the chucking pin and hole are not fitted, the hub starts rotating a little later due to friction with the turntable. .

[0032] In this case, if the number of holes is extremely small, it will take time for the pins to fit into the holes, so at that point both the hub and the turntable are rotating and the relative speeds are Becomes less accurate. On the other hand, when the number of holes becomes a certain number, the relative speed becomes considerably high at the time of the fitting. Further, when the number of holes increases, the rotational speed of the turntable has not yet increased sufficiently at the time of fitting, and thus, contrary to the above, the relative speed decreases.

[0033] The impact when the pin and hole fit together increases in accordance with the relative speed. For this reason, the lifespan of the chucking mechanism such as the pin and its supporting members is as shown in Figure 3.
When the number of holes is extremely small, it is slightly high, becomes low when the number is constant, and then gradually increases as the number of holes increases.

In this embodiment, since a large number of holes 42a and 52a are formed adjacent to each other on the circumference of the molded parts 42 and 52, the impact when the pin 82 is fitted is extremely small, and the chatter is The life of the king mechanism can be extended.

Although the above-described embodiments have been explained using an optical disk device as an example, it goes without saying that the present invention can be similarly applied to other disk devices such as magnetic disks and magneto-optical disks.

[0036]

As described above, according to the present invention, the hub mechanism is constructed of a core part made of a magnetic material and a molded part made of a synthetic resin.
The overall weight is reduced and the load on the spindle motor is reduced. In addition, we formed a hole in the synthetic resin mold part to fit the chucking pin, making it easier to process and reducing processing costs. Since a large number of holes are formed, mechanical impact is reduced when the holes and pins fit together, and the durability of the chucking mechanism is improved.

[Brief explanation of the drawing]

FIG. 1 is a partial cross-sectional view of a chucking section of an optical disc device according to an embodiment of the present invention.

FIG. 2 is an external perspective view of the hub.

FIG. 3 is a graph showing the relationship between the number of chucking holes and the life of the chucking part.

FIG. 4 is an external perspective view of a conventional hub.

[Explanation of symbols]

3. Optical disc 4,5 Hub 41, 51 Core metal part 42, 52 Mold part 6 Spindle motor 61 axis 41a, 41c, 52a holes 41b, 42a, 52a holes 7 Screws 8 Turntable 81 Magnet 82 pin 83 Leaf spring

Claims (2)

[Claims] Claim 1: In a disk hub mechanism that is fixed at the center of the disk, which is an information storage medium, and is chucked by a turntable when the disk is rotated, the entire disk is shaped like a disk, and the center portion is It has a core metal part made of magnetic material and has a hole that fits into the rotating shaft of the turntable side, and a disk is fixed around the core metal part and fixed to the outer edge part, and it is made of synthetic resin. A disk hub mechanism comprising a molded portion. 2. The mold part is characterized in that a large number of holes are formed adjacent to each other on the circumference at a constant radius from the center, into which chucking pins on the turntable side are fitted. Hub mechanism for the disc described.