JPS6217Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a light beam irradiation device for an optical reading device that irradiates a light beam onto a disk on which information is optically recorded and reads the information.

In the conventional light beam irradiation device of this type of optical reading device, it is used to perform tracking control to prevent the light beam from deviating from the information track on the disk, or jitter control to correct temporal errors in the information track direction. In addition, the mirror itself was rotated to change the light beam irradiation device, and the focusing lens was moved up and down as an automatic focusing device to keep the spot diameter of the light beam on the disk constant. In this case, as a support and elastic member for the mirror or focusing lens, etc., a damper made of piano wire or cloth impregnated with resin and having a corrugated cross-section of concentric circles has been used. However, these supporting and elastic members are very light.
However, it is difficult to support a main body of a light beam irradiation device that includes many lenses, mirrors, etc., and good vibration characteristics cannot be obtained.

In view of the above-mentioned drawbacks of the light beam irradiation device of the conventional optical reading device, the present invention can support a relatively large weight of the light beam irradiation device, has sufficient vibration characteristics, and has a simple structure. The purpose of the present invention is to provide a light beam irradiation device for an optical reading device that irradiates a light beam onto a disk on which information is optically recorded and reads the information. The apparatus includes a light beam irradiation device main body having lenses, mirrors, etc. for irradiating a light beam, and two parallel support plates, the light beam irradiation device main body being parallel to the disk between the support plates. a frame for holding the disc so as to be movable; and a means for moving the frame parallel to the disk; a rolling element is interposed between the light beam irradiation device main body and one of the support plates; A light beam irradiation device for an optical reading device is characterized in that the main body of the light beam irradiation device and the other support plate are connected by an elastic body.

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 6 show an embodiment of the present invention. In the figures, A is a disc-shaped disk on which information is recorded in optical form, and is designed to rotate at a constant speed. Reference numeral 1 denotes a main body of the light beam irradiation device, which includes cylindrical hollow parts 1a and 1b that communicate with each other at right angles, and cylindrical hollow part 1 that communicates with the hollow part 1b at right angles with each other.
It has c. A hollow cylindrical movable body 2 is held in the hollow portion 1a at two locations, an upper portion and a lower portion thereof, via dampers 3a and 3b, respectively, so as to be vertically movable. The movable body 2 has a focusing lens 4 on its upper part that focuses a light beam emitted from a light beam emitter described later onto the disk A, and a yoke 5 fixed to one end of a hollow part 1a and a yoke 5 fixed to one end of the hollow part 1a in its lower part. It has an electromagnetic coil 7 that is loosely inserted between the magnet 6 and the magnet 6 attached to the magnet 6. A separately obtained control signal for focus adjustment is applied to the electromagnetic coil 7, and the entire movable body 2 moves up and down in accordance with the control signal to adjust the focus on the disk A. 8 is a hole provided in a part communicating with the hollow part 1b of the movable body 2, 9 is a mirror attached to the magnet 6 via the height adjustment member 10, and the light incident from the hollow part 1b is passed through the hole 8. The light is guided through the mirror 9 to the focusing lens 4. Hollow part 1b
A light beam emitter 13 having a semiconductor laser 11 and a coupling lens 12 is fixed thereto, and a λ/4 plate 14 is attached near the hollow portion 1a. Further, a light receiver 15 is fixed to one end of the hollow portion 1c, and a holder 18 for holding a lens 16 and a deflection beam splitter 7 is inserted. The deflection beam splitter 17 is arranged so as to be located at the intersection of the hollow parts 1b and 1c. 19 and 20 are electromagnetic coils attached to the side walls 1d and 1e of the main body 1 of the light beam irradiation device, respectively.

Reference numeral 21 denotes a frame body that supports the light beam irradiation device main body 1, and a support plate 2 held in parallel at a predetermined interval.
2 and 23, and is driven by a drive device (not shown) to move parallel to the disk A from the outer periphery toward the center at a constant speed. 24 is a hole 2 bored in the side wall 21a of the frame 24.
The electromagnetic coil 19 is held between a yoke fixed to the yoke 1a' and a magnet 25 attached to the center of the yoke. Similarly, 26 is the side wall 21 of the frame body 21.
The electromagnetic coil 20 is loosely inserted between a yoke fixed to a hole 21b' bored in the hole 21b' and a magnet 27 attached to the center of the yoke. Electromagnetic coil 1
Tracking control signals and jitter control signals obtained separately are added to 9 and 20, and the light beam irradiation device main body 1 moves horizontally in accordance with the signals.
Tracking errors and jitter are corrected.

The support plate 22 has a hole 22 that communicates with the hollow portion 1a of the light beam irradiation device main body 1 and allows the yoke 5 to move freely.
a, and the support plate 23 supports the lens 4 of the movable body 2.
It has a hole 23a that protrudes so as to be movable. As shown in FIG. 3, four rolling elements 28 made of synthetic resin balls made of non-magnetic material are interposed between the support plate 22 and the lower surface 1f of the light beam irradiation device main body 1. It is housed in four holes 29a of a position regulating plate 29 made of a synthetic resin plate made of non-magnetic material,
The support plates 22 are regulated in their mutual positions.
It is also rotatable with respect to the lower surface 1f of the main body 1 of the light beam irradiation device. Further, between the support plate 23 and the upper surface 1g of the light beam irradiation device main body 1, a cylindrical elastic body 30 made of silicone rubber or the like is elastically installed as shown in FIG.
are pressed against the frame 21 via rolling elements 28.
The upper end of the elastic body 30 engages with the engagement recess 23b formed in the support plate 23, and the lower end engages with the engagement recess 1h formed in the upper surface 1g of the light beam irradiation device main body 1, thereby causing the frame 21 and the light beam irradiation device main body 1 are horizontally connected to perform a returning action when the light beam irradiation device main body 1 moves in the horizontal direction. The engaging recess 1h has an inclined side surface 1h' in order to facilitate engagement of the elastic body 30 and to provide relief when the elastic body 30 is compressed and expands laterally. ing. Further, the support plate 22 has a fifth
As shown in the figure, a pin 31 that passes through the through hole 20b of the position regulating plate 29 and is loosely inserted into the hole 1i of the light beam irradiation device main body 1 is screwed, and the light beam irradiation device main body 1 is attached to the frame 21. On the other hand, it prevents it from moving outside the movement control range or falling off. Note that FIG. 6 shows an exploded perspective view showing the positional correspondence between the rolling elements 28 and the position regulating plate 29, in which the through hole 29c of the position regulating plate 29 is located in the hollow portion 1a of the light beam irradiation device main body 1. Correspondingly, it is provided to allow the yoke 5 to be loosely inserted.

Next, we will discuss the operation. When reading information, disk A rotates at a constant speed, and frame 2
1 is driven along with support plates 22 and 23 by a drive device (not shown) so as to move in parallel from the outer periphery of disk A toward the center. Semiconductor laser 11
The light beam emitted from the cut-up lens 1
2. The beam passes through the deflection beam splitter 17 and the λ/4 plate 14, and enters the mirror 9 from the hole 8 of the movable body 2, where it enters the mirror 9.
Disk A is turned 90 degrees and focused by focusing lens 4.
It is focused on the top and illuminates its information track. The light beam reflected from the disk A passes through the focusing lens 4, the mirror 9, and the λ/4 plate 14 again and enters the deflection beam splitter 17, where it is reflected toward the lens 16 and enters the light receiver 15. The track information of the disk A taken out by the light receiver 15 is input to a control circuit (not shown), where an information signal is taken out, as well as a focus adjustment control signal, a tracking control signal, and a jitter control signal. It is input to electromagnetic coils 7, 19 and 20. Focus adjustment on the disk A is performed by the excitation of the electromagnetic coil 7, yoke 5, and magnet 6, which causes the movable body 2 and the focusing lens 4 attached to the upper part of the movable body 2 to move up and down. Tracking control and jitter control are performed by the excitation action of the electromagnetic coil 19, yoke 24, and magnet 25, and the excitation action of the electromagnetic coil 20, yoke 26, and magnet 27, so that the light beam irradiation device main body 1 is controlled by the support plate 2 of the frame 21.
2 and 23 through a rolling element 28.

In the above embodiment, the rolling elements 28 and the position regulating plate 29 are made of non-magnetic synthetic resin, but this is caused by the magnetic force of the magnets 6, 25, 27 and yokes 5, 24, 26 located nearby. This is to avoid being directly affected.

FIG. 7 shows another embodiment of the rolling element 28 and the position regulating plate 29 in a case where only the tracking control is required among the tracking control and jitter control of the light beam irradiation device main body 1. That is, the rolling element 28' is a cylindrical roller made of a non-magnetic synthetic resin, and the hole 29a' of the position regulating plate 29' regulates the position of the roller 28' and each other, and also controls one-way tracking. It has a rectangular shape so that it can roll freely in both directions. Other configurations and operations are the same as those in the previous embodiment. It goes without saying that if only jitter control is to be performed, the rolling element 28' and the hole 29a' of the position regulating plate 29' may be rotated by an angle of 29a'.

Although the position regulating plates 29 and 29' are formed separately from the frame 21, they may be formed directly on the frame 21 or the support plate 22 if they regulate the mutual positions of the rolling elements 28 (28'). It may be something.

As described above, according to the present invention, in a light beam irradiation device of an optical reading device that irradiates a light beam onto a disk on which information is optically recorded and reads the information, the lens and mirror for irradiating the light beam are used. a frame body having two parallel support plates and movably holding the light beam irradiation device body between the support plates; and a frame body having the frame body parallel to the disk. a rolling element is interposed between the light beam irradiation device main body and one support plate, and the light beam irradiation device and the other support plate are connected by an elastic body. Therefore, the main body of the light beam irradiation device can move smoothly while being reliably guided between the support plates of the frame by the rolling elements, and the elastic body simply moves the main body of the light beam irradiation device elastically between the support plates. The trowel not only has a return function against the movement of the light beam irradiation device main body, but also has an extremely simple structure, has good vibration characteristics, and can reliably support a relatively heavy light beam irradiation device main body. This is useful as a small-sized light beam irradiation device.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention. Fig. 1 is a sectional plan view of the main part of the light beam irradiation device, Fig. 2 is a sectional front view of the main part of the light beam irradiation device, and Fig. 3 is a rolling element insertion part. Fig. 4 is an enlarged sectional view of the elastic body insertion part, Fig. 5 is an enlarged sectional view of the pin insertion part, Fig. 6 is an exploded perspective view of the rolling element and position regulating plate, and Fig. 7 is an enlarged sectional view of the elastic body insertion part. FIG. 2 is an exploded perspective view of a rolling element and a position regulating plate in the embodiment. 1... Light beam irradiation device main body, 21... Frame body,
22, 23...Support frame, 28...Rolling element, 30...
...Elastic body, A...disc.

Claims (1)

[Claims for Utility Model Registration] (1) Lenses and mirrors for irradiating a light beam in a light beam irradiation device of an optical reading device that irradiates a light beam onto a disk on which information is optically recorded and reads the information. a frame body having two parallel support plates and holding the light beam irradiation device body so as to be movable in parallel with the disk between the support plates; and the frame body. means for moving the body parallel to the disk, a rolling element is interposed between the light beam irradiation device main body and one support plate, and the light beam irradiation device main body and the other support plate are elastically moved. A light beam irradiation device for an optical reading device, characterized in that the device is connected by a body. (2) A light beam irradiation device for an optical reading device according to claim 1, which includes a plurality of rolling elements and means for regulating the mutual positions of the rolling elements. (3) Utility model registration claim 1, in which a position regulating plate with a hole into which a rolling element is freely inserted is movably arranged between the main body of the light beam irradiation device and one of the support plates. A light beam irradiation device for an optical reading device according to item 1 or 2. (4) A light beam irradiation device for an optical reading device according to any one of claims 1 to 3, wherein the rolling elements are made of synthetic resin. (5) A light beam irradiation device for an optical reading device according to claim 3 of the utility model registration claim, wherein the position regulating plate is made of synthetic resin. (6) A light beam irradiation device for an optical reading device according to any one of claims 1 to 4, wherein the rolling elements are formed of spheres. (7) A light beam irradiation device for an optical reading device according to any one of claims 1 to 4, wherein the rolling elements are formed of cylindrical rollers. (8) A light beam irradiation device for an optical reading device according to claim 1, wherein the side surface of the engaging recess for engaging the elastic body with the main body of the light beam irradiation device is an inclined surface.