JPH02199631A - Optical information recording and reproducing device - Google Patents

Abstract

PURPOSE:To increase the strength of a base for a driving motor without enlarging the device and to enable the stable information recording/reproducing by specifying the base as a ferromagnetic substance and incorporating it in a part of a magnetic circuit for the motor. CONSTITUTION:The base 21 is formed of the ferromagnetic substance made of a ferrous alloy. Magnetic flux from permanent magnets 30 and 31 flows through an upper yoke 29, a center yoke 28 and the base 21, and when a coil is electrified, thrust is generated for an optical head 24 in the axial direction of a guide rail 22. Now, since the strength of the base 21 is large for its material, acting as a lower yoke for the linear motor 25, the space required for providing the lower yoke can be omitted. By this method, the strength of the base 21 is promoted without enlarging the device, and bad influence on the recording/reproducing operation due to resonance is prevented.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is a method of recording information by irradiating the surface of an information recording medium with light.
The present invention relates to an optical information recording/reproducing device that performs reproduction or erasing.

[Prior Art] Figure WIJ4 shows a configuration diagram of a conventional optical information recording/reproducing device, in which a base 1 includes a spindle motor 2 for rotating an optical disk. A near motor 4 and a guide rail 5 for driving the optical disc 3. Optical components such as a linear sensor 6 and a linear encoder plate 7 that detect the position of the optical head 3 are attached to the optical head 5 to prevent tracking and focus of the optical head 3 from being lost due to external vibrations, shocks, etc. A vibration isolation mechanism 8 is used.

FIG. 5 shows a configuration diagram of the beam near motor 4. A yoke 11 is inserted through a bobbin 10 around which a coil 9 is wound, and yokes 12 and 13 each having a U-shaped cross section are arranged parallel to the yoke 11. Both ends are connected to the yoke 11, respectively. Furthermore, permanent magnets 14.15 are arranged on the surface of the yoke 12.13 facing the yoke 11.

When the magnetic flux from the permanent magnets 14, 15 passes through the yoke 11, 12, 13, which is a ferromagnetic material, and the coil 9 is energized, a thrust is generated in the axial direction of the coil 9. FIG. 6 shows the structure of the base l, in which the base l has a substantially rectangular frame made of aluminum or the like, with its center part relayed by a reinforcing member 16, and has two large holes 17 and 18. ing. The linear motor 4 and many of the optical components are located in these holes 17 and 18.
The device is thinned by the thickness of the holes 17 and 18.

However, since the base 1 in this case does not have sufficient structural and material strength, it resonates due to the vibrations of the spindle motor 2 and the near motor 4, which adversely affects the tracking and focus control of the optical helad 3. There is a problem.

[Objective of the Invention 1 The object of the present invention is to solve the problems of the conventional method, increase the strength of the base without increasing the size of the device, and provide an optical system capable of stably recording and reproducing information. An object of the present invention is to provide a type information recording/reproducing device.

[Summary of the invention] The gist of the present invention is to achieve the above objects.

In an optical information recording and reproducing device that records and reproduces information, the base of the drive motor is made of ferromagnetic material.

The optical information recording/reproducing device is characterized in that the base is a part of the magnetic circuit of the motor.

[Embodiments of the Invention] The present invention will be described in detail based on embodiments illustrated in FIGS. 1 to 3.

1 and 2 show a first embodiment. In FIG. 1, a base 21 is made of a ferromagnetic material made of an iron-based alloy, and two guide rails 22 are provided at the center of the base 21. An optical head 24 is supported on these guide rails 22 via bearings 23 and is slidable along the guide rails 22. In addition, the guide rail 22
There are two drive means for the optical head 24 on both sides along the
A platform near motor 25 is installed.

FIG. 2 is a sectional view of the beam near motor 25, and the coil 26
A center yoke 28 is inserted through the bobbin 27 in parallel with the guide rail 22, and an upper yoke 29 is arranged above the bobbin 27. Both ends of the center yoke 28 and the upper yoke 29 are attached to the base 2.
It is fixed at 1. Further, permanent magnets 30 and 31 are arranged on the lower surface of the upper yoke 29 and the upper surface of the base 21.

In the above configuration, the magnetic flux emitted from the permanent magnets 30 and 31 flows inside the upper yoke 29, the center yoke 28, and the base 21, and when current flows through the coil 26, the optical head 2
4, a thrust is generated in the axial direction of the guide rail 22. Here, the base 21 made of ferromagnetic material has high strength as a material and also serves as a lower yoke in the linear motor 25, so that the space required for providing the lower yoke can be omitted. Furthermore, since no hole is formed in the base 21, it has high structural rigidity and can efficiently guide magnetic flux, thereby increasing the output of the linear motor 25.

FIG. 3 shows a second embodiment, and the base 4 is made of two ferromagnetic materials.
An opposing yoke 41a is installed at the mounting position of spindle motor 1.
, 41b are integrally formed, and the base 41 also serves as an opposing yoke for the spindle motor. In addition, Fig. 1.

The same reference numerals as in FIG. 2 indicate the same members. With this configuration as well, the same effects as in the first embodiment can be obtained.

Note that the present invention can be applied not only to the embodiments described above, but also in cases where the linear motor is placed only on one side, where only the actuator that performs the focusing or tracking operation of the optical head is sought, and where the optical head is rotated. This can also be applied to cases where a so-called swing arm is used to seek in a substantially radial direction.

[Effects of the Invention] As explained above, in the optical information recording and reproducing device according to the present invention, the base of the motor is formed of a magnetic material and serves as a yoke, so that the base can be used without increasing the size of the device. The strength of the stand can be improved, and adverse effects on recording and reproducing operations caused by resonance can be prevented.

[Brief explanation of the drawing]

Drawings 1 to 3 show an embodiment of an optical information recording/reproducing device according to the present invention, and FIG. 1 is a perspective view of the first embodiment;
Fig. 2 is a sectional view of the beam near motor, Fig. 3 is a perspective view of the second embodiment, Fig. 4 is a perspective view of the conventional example, Fig. 5 is a perspective view of the beam near motor, and Fig. 6 is a perspective view of the base. FIG. 21.41 is a base, 24 is an optical head 225 is a linear motor, 26 is a coil, 28 is a center yoke, 29 is an upper yoke, 30.31 is a permanent magnet, and 41a, 41b are opposing yokes.

Claims (1)

[Claims] 1. An optical information recording and reproducing device for recording and reproducing information, characterized in that the base of the drive motor is made of a ferromagnetic material, and the base is part of the magnetic circuit of the motor. Information recording and reproducing device.