JPH01258257A - Optical disk revolving mechanism - Google Patents

Abstract

PURPOSE:To prevent the set dislocation of an optical disk at the time of using high temperature by providing a shaft center hole on the rotary shaft of a motor, integrating a shaft to have a semi-sphere-shaped leading part which is movable in a shaft direction and engaging the semi-sphere-shaped leading part with the center hole of the optical disk. CONSTITUTION:Just before an optical disk 5 is placed on a turn table 4, a center hole 5b of the optical disk 5 and a semi-sphere-shaped head part 3a of a shaft 3 are brought into contacted with each other and engaged and the centering of the optical disk 5 is executed. Next, when the optical disk 5 is pressed down by the pressing-down force of a clamp 6, simultaneously, the semi-sphere-shaped leading part 3a is also lowered and the optical disk 5 is pressurized contact to the turn table 4. Thus, by engaging the semi-sphere-shaped leading part 3a and the center hole 5b of the optical disk 5, the set dislocation can be prevented from being generated at high temperature, when a room temperature and a temperature in a device are increased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical disc rotation mechanism, and more particularly to an optical disc rotation mechanism that is unique in positioning an optical disc.

[Prior Art] Conventionally, this type of optical disc rotation mechanism was as shown in FIG.

That is, a turntable 4 is installed coaxially with the rotating shaft 2 of the motor 1 using the motor 1 as a power source, an optical disk 5 is set on the turntable 4, and a rotatable turntable 4 is mounted on the turntable 4 to prevent the optical disk 5 from slipping during rotation. The structure is such that the clamp 6 is brought into pressure contact.

When positioning the center of the optical disc 5, the fitting protrusion 4a of the turntable 4 attached to the outer periphery of the tip of the rotating shaft 2 of the motor 1 and the center hole 5a of the optical disc 5 are fitted, and then rotated freely. The clamp 6 was brought into pressure contact.

[Problems to be Solved by the Invention] In the conventional optical disc rotation mechanism described above, the turntable 4 has a fitting protrusion 4a for aligning the center hole 5a of the optical disc 5 with the rotation axis 2 of the motor 1. When the optical disc 5 is set on the turntable 4, the center hole 5a of the optical disc 5 is fitted into the fitting protrusion 4a, which is pressed against the clamp 6. is made of metal such as stainless steel or aluminum, whereas the substrate of the optical disc 5 is often made of plastic. In this case, since there is a large difference in the coefficient of thermal expansion, if the room temperature or the temperature inside the device increases,
The clearance at the fitting portion becomes large, which causes misalignment of the optical disk 5, which increases the eccentricity of the recording and reproducing tracks during one rotation, which has a disadvantage in that the recording and reproducing characteristics are adversely affected.

[Means for Solving the Problems] The present invention has been made to solve the above problems, and as a means for solving the problems, an optical disc rotation mechanism of the present invention includes a motor for rotating an optical disc, and a rotation mechanism of the motor. The motor includes a turntable attached to the outer periphery of the tip of the shaft, and a rotatable clamp that presses the optical disc against the turntable, and the motor has an axial hole that penetrates the rotating shaft, and a turntable that passes through the rotating shaft. A shaft having a hemispherical head protruding toward the table side is inserted, and the shaft is biased toward the turntable by a spring arranged in the shaft center hole, and
The center hole of the optical disk is configured to engage the hemispherical head of the shaft.

[Example] Next, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view of an optical disc rotation mechanism according to an embodiment of the present invention.

This optical disc rotation mechanism includes a motor 1 for rotating an optical disc 5, a turntable 4 for mounting the optical disc 5 attached to the outer periphery of the tip of a rotating shaft 2 of the motor 1, and a press-fitting of the optical disc 5 onto the turntable 4. A clamp 6 is provided.

Further, the motor 1 has a shaft center hole 2a passing through the rotating shaft 2.

A shaft 3 is inserted through the shaft hole 2a so as to be movable in the axial direction. A hemispherical head 3a that protrudes toward the turntable 4 is provided at the end of the shaft 3 on the turntable 4 side. This hemispherical head 3a is located at the center hole 5b of the optical disc 5.
It is formed slightly larger than the diameter of the Further, the lower side of the shaft 3 in the figure is connected to a coil spring 14 disposed in the shaft center hole 2a, and the shaft 3 is biased toward the turntable 4 via this coil spring 14. .

Then, just before the optical disc 5 is placed on the turntable 4, the center hole 5a of the optical disc 5 and the hemispherical head 3a of the shaft 3 come into contact with each other, and the optical disc 5 is centered.

Next, the optical disc 5 is pressed down by the pressing force of the clamp 6, and at the same time, the hemispherical head 3a is also lowered, and the optical disc 5 is pressed against the turntable 4.

Thereafter, when the motor 1 is started and reaches steady rotation, it becomes possible to record on or reproduce from the optical disc 5.

[Effects of the Invention] As explained above, the present invention provides a shaft center hole in the rotating shaft of a motor, incorporates a shaft having a hemispherical head movable in the axial direction, and connects the hemispherical head with an optical disc. Since the center hole is engaged with the center hole, it is possible to eliminate the negative effect of the conventional fitting method of increasing the fitting gap during high-temperature use.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an optical disk rotation mechanism according to an embodiment of the present invention, and FIG. 2 is a sectional view showing a conventional optical disk rotation mechanism. 1: Motor 2: Rotating shaft 2a: @hole
3: Axis 3a: Hemispherical head 4: Turntable 4a:
Fitting protrusion 5: Optical disc 6: Clamp 14: Coil spring

Claims (1)

[Claims] A motor for rotating an optical disk, a turntable attached to the outer periphery of a tip of a rotating shaft of the motor, and a rotatable clamp for pressing the optical disk against the turntable, the motor passing through the rotating shaft. A shaft having an axial center hole, a shaft having a hemispherical head protruding toward the turntable is inserted into the axial center hole, and the shaft is biased toward the turntable by a spring arranged in the axial center hole. An optical disc rotation mechanism characterized in that the center hole of the optical disc and the hemispherical head of the shaft are engaged with each other.