JPS626581Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention is an optical system for recording or reproducing signals such as audio or video by projecting a light beam such as a laser beam onto a disc-shaped recording medium while rotating the disc-shaped recording medium. The present invention relates to an optical disc recording/reproducing device, and more particularly to an optical disc recording/reproducing device that facilitates adjustment and assembly of each part and easily obtains desired accuracy.

For example, in an optical disk recording/reproducing device such as a Philips-type video disk player, a needle is not used as a scanning element, so various considerations are required to scan the beam in a concentric or spiral track form. Become. According to a design that does not consider mass productivity, it is relatively easy to obtain the desired accuracy, but it is quite difficult to increase the mass productivity and obtain the desired accuracy. This requires precision and control in micron units, and has moving parts such as a disk rotation drive unit, a radial feed drive unit for the optical device, a rotating mirror for tracking control, and a focus actuator for focus control. It's for a reason.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an optical disk recording/reproducing device that facilitates the adjustment and assembly of each part, makes it possible to easily obtain the desired accuracy, and further enables mass production.

To achieve the above object, the present invention includes a disk drive section for holding a recording or reproducing disk and rotationally driving the disk, and an optical section for projecting a recording or reproducing beam onto the disk. an optical disk comprising: a guide section that guides the optical section in the radial direction of the disk; and a radial feed drive section that moves the optical section guided by the guide section in the radial direction of the disk. In the recording and reproducing apparatus, the optical section includes at least a light source and an optical system for projecting a light beam emitted from the light source onto the disk and guiding a reflected beam obtained from the disk to its detection position. , a beam detector for detecting the reflected beam, and the light source, the optical system, and the beam detector are attached to the same optical part substrate, and the optical part is separate from the guide part. An optical system configured to be assembled together, wherein the guide section includes a guide rail and a sliding board guided by the guide rail, and the optical part board is mounted at a predetermined position on the sliding board. This relates to a type disk recording/reproducing device.

According to the above invention, the following effects can be obtained.

(b) In addition to the optical part board, a sliding board is provided to constitute the guide part, and the optical part board is mounted at a predetermined position on this sliding board, so it is independent of the guide part. It is possible to assemble the optical section. Therefore, the optical part can be easily assembled, and the optical part can be adjusted independently of the guide part.

(b) Since the optical section integrally includes a light source, an optical system, and a reflected beam detector, it is possible to easily assemble all parts related to light. Further, the relationship between the projected beam and the reflected beam can be adjusted independently of the guide section.

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

In FIG. 1, which shows the principle of a disk player according to an embodiment of the present invention, a disk motor 2, a turntable 3, and a clamper 4 are provided as a disk drive unit for rotating a disk 1 at, for example, 1800 rpm. It is being The optical section 5 shown surrounded by a dotted line includes a laser light source 6 consisting of a He-Ne laser tube, a concave lens 7, a diffraction grating 8, a beam splitter 9, a 1/4λ plate 10, a fixed mirror 11, a rotating mirror 12, and a condenser. It consists of a lens 13, a half mirror 14, a main beam detector 15, and a sub beam detector 16. The beam emitted from the laser light source 6 of this optical section 5 reaches the diffraction grating 8 via the concave lens 7.
Here, a main beam 17 and a sub beam (not shown) are formed. The main beam 17 and sub beams are projected onto the disk 1 via a beam splitter 9, a 1/4λ plate 10, a fixed mirror 11, a rotating mirror 12, and a condensing lens 13, and the reflected beam of the main beam 17 is thereby generated. 18 and the reflected beam 19 of the sub beam
reaches the half mirror 14 via the condensing lens 13, rotating mirror 12, fixed mirror 11, 1/4λ plate 10, and beam splitter 9, and the reflected beam 18 of the main beam is detected by the main beam detector 15. , the reflected beam 19 of the sub-beam is detected by the sub-beam detector 16. In this embodiment, information is read by the reflected beam 18 of the main beam 17, and the focus is detected by the change of the beam spot on the main beam detector 15, i.e. by the condenser lens 13.
The distance between the laser beam and the disk 1 is detected, and the beam position for tracking is detected using the reflected beam 19 of the sub beam.

The optical section 5 as described above has first and second guide rails 20 and 21 extending in the radial direction of the disk 1.
At the same time, it is locked by a locking piece 23 to an endless wire 22 that extends in the radial direction of the disk and serves as a drive belt. wire 22
is wound around a first pulley 24 and a second pulley 25 that are arranged opposite each other, and is driven by a radial direction feed drive section 26 to move in both left and right directions. The feed drive unit 26 consists of a feed motor 27, a group of gears (not shown in FIG. 1) meshing with this rotating shaft, and a drive pulley 28 around which a wire 22 is wound.
By switching the rotation direction of the motor 27, the wire 22
This is to drive the motor both to the left and to the right. In this embodiment, the first pulley 24 is a fixed pulley, and the second pulley 25 is a displaceable pulley mounted on a tensioning lever 29. The lever 29 is rotatable about a shaft 30, and is biased counterclockwise in FIG. 1 by a spring 31.

The disk 1, which is held on the turntable 3 by the clamper 4, has a width of about 1 mm as shown in FIGS. 2 and 3.
Information such as a video signal or an audio signal is transferred to a spiral track 33 by an optical recess or pit 32 having a depth of approximately 1/4λ (here, λ is the wavelength of the laser beam) and a length of 1.5 to 6 μm. Generally, as shown in Fig. 3, a transparent resin layer 34 having an uneven surface corresponding to the pits 32, a reflective film 35 coated on the uneven surface of the resin layer, and a protective film are used. It consists of a protective film 36.

Since the diameter of the spot of the main beam 17 projected onto the track of the disk 1 as described above is larger than the width of the pit 32, the main beam 17 is projected onto the pit 32.
is being projected, the reflected light inside the pit 32 and the reflected light outside the pit cancel each other out, reducing the reflected output, and the main beam 17 is projected onto an area where there is no pit 32.
is projected, no cancellation occurs, so the reflected output becomes large. Therefore, by detecting the intensity of the reflected light with the main beam detector 15, the presence or absence of the pit 32, that is, information can be read. In this embodiment, the main beam detector 15 is a small first beam detector.
Since it is composed of a detector and a second detector surrounding it, the sum of the outputs of the first and second detectors is used for information detection, and the output of the first detector is used for focus detection. It is used to detect the distance between the condenser lens 13 and the disk 1. Although the sub-beam is not shown in FIG. 2, it is projected in a predetermined relationship with the main beam 17 so that a portion thereof covers the pit 32;
The position of the main beam 17 with respect to the pit 32 is detected.

FIG. 4 specifically shows the disc playback device shown in FIG. 1, and FIGS. 5, 6, and 7 show a part of the device shown in FIG. 4 in detail. Therefore, parts common to those in FIG. 1 are given the same reference numerals. As is clear from FIG. 4, this disc playback device is provided with a rectangular metal frame 37, and a disc drive unit 3 is mounted on the upper surface of this frame 37.
8 mounting boards 39 are removably mounted with four screws 40. The disk motor 2 is attached to the lower part of the mounting board 39, and the turntable 3 rotated by the disk motor 2 is arranged on the upper surface thereof, so that only the disk drive section 38 is configured independently and then attached to the frame 37. Is possible. It is also possible to remove only the disk drive section 38 from the frame 37.

The first and second guide rails 20 and 21 extending left and right in FIG. is slidably supported. Since the substrate 46 of the optical section 5 is attached to the sliding substrate 44 with three screws 45,
The optical section 5 moves in accordance with the movement of the sliding substrate 44. Further, since the laser light source 6 is fixed to the lower part of the substrate 46 of the optical section 5, the laser light source 6 also moves together with the sliding substrate 44. Also, the optical part 5 is screw 45.
Since it is removably connected to the sliding substrate 44, it is possible to assemble and adjust only the optical section 5 independently as shown in FIG. 7, and then connect it to the sliding substrate 44. The optical part 5 is provided with a focus actuator 47 in addition to the one shown in FIG.
stands out from Focus actuator 47
The condenser lens 13 is supported by a spring 49, and the condenser lens 13 is vertically displaced by passing a focus control current through a moving coil (not shown).

A fixed roller 4 having elasticity is mounted on a roller mounting plate 51 attached to one end of the sliding board 44 with a screw 50.
2 is attached by a shaft 52, and an elastic pressure roller 43 is attached via a pressure roller mounting plate 53. Since the pressure roller 43 must be freely displaceable, a rotation plate 54 is attached to the pressure roller mounting plate 53 with a support shaft 55, and the pressure roller 43 is attached to this rotation plate 54 with a shaft 56. In addition, in order to press the pressure roller 43 onto the guide rail 21, one end of the torsion spring 57 wound around the support shaft 55 presses the rotating plate 54 clockwise in FIG. 6, and the other end engages with the pin 58. are doing. A pin 59 provided above the rotating plate 54
is a stopper for limiting the position of the rotating plate 54 when the roller 43 is not in contact with the guide rail 21. Note that the pressure roller mounting plate 53 is removably attached to the roller mounting plate 51 with two screws 60.

A locking piece 23 is fixed to the sliding board 44 guided by the two guide rails 20 and 21, and the wire 22 made of stranded metal wire and the sliding board 44 are connected by the locking piece 23. There is. In addition, since the connection by the locking piece 23 is performed using the screw 61,
The wire 22 and the sliding substrate 44 are a separable connection.

Pulley support plate 62 that supports first pulley 24
is fixed to the frame 37 with screws 63.
The left side of the frame 37 has a radial feed drive unit 2.
6 support substrates 64 are removably attached with screws 65. Then, the tension applying lever 29 is mounted on the support substrate 64 with the shaft 30,
This lever 29 is biased clockwise in FIG. 4 by a spring 31 which presses this rising portion 66 at one end. The spring 31 is a torsion spring wound around the shaft 30, and the other end is locked to the support substrate 64.

A gear group 67 is provided between a feed motor 27, which is a drive source in the radial feed drive unit 26, and a drive pulley 28, and as the feed motor 27 rotates, the drive pulley 28 rotates. A wire 22 is wound several times around the drive pulley 28, as shown in FIG.

As mentioned above, four mounting holes 68 are provided in the frame 37 to which the main parts of the disc playback device are mounted. Therefore, after the attachment of each part to the frame 37 is completed, the frame 37 is fixed to the attachment portion provided on the main body case, and the device is completed.

In the apparatus configured as described above, if the disk 1 shown in FIG. 2 is placed on the turntable 3 and the disk motor 2 is rotated, the disk 1 will rotate at a predetermined speed. Further, when the feed motor 27 is driven based on the radial direction feed signal, the wire 22 moves to the left or right, and following this, the optical section 5 attached to the sliding board 44 moves in the disk radial direction. As a result, the beam projected from the condenser lens 13 performs spiral scanning. In addition, by controlling the rotation angle of the rotation mirror 12 with a tracking control signal, the beam position on the disk 1 is controlled, and by controlling the condensing lens 13 with the focus actuator 47, focus control is performed. It will be done.

As is clear from the above, according to this example,
A rectangular frame 37 is provided, and the disk drive unit 3
8 and the radial feed drive section 26 are independently provided and removably attached to the frame 37, and the optical section 5 is detachably attached to the sliding substrate 44, so that the optical section 5 and the radial direction feed drive section 26 are provided independently and detachably attached to the frame 37. This allows the section 26 and the disk drive section 38 to be assembled and adjusted independently before being attached to the frame 37. Therefore, assembly and adjustment are facilitated, and mass productivity is improved. Furthermore, since each part can be removed from the frame 37, repair and replacement after assembly is facilitated.

Also, the wire 2 constituting the radial direction feed drive section 2
2 is not hung between the driving pulley and the driven pulley, but the first pulley 24 and the wire 2 are fixedly arranged.
Since the driving pulley 28 is arranged between the second pulley 24 and the second pulley 24 to which a biasing force is applied in the direction of applying tension to the wire 22, even if the wire 22 is stretched, the wire 22 can be loosened. The rotation of the drive pulley 28 can be accurately converted into direct movement of the sliding base plate 44.
Further, a wire 22 is wound around the drive pulley 28.
The drive pulley 28 is connected to the first and second pulleys 24, 2
5, the tension of the wire 22 can be prevented from acting on the rotating shaft of the drive pulley 28 at all.

In addition, in this embodiment, two guide rails 20 and 21 arranged in parallel as a guide part and a sliding board 44
A bearing 41 is provided on one side of the sliding board 44.
The other side of the sliding board 44 is engaged with the second guide rail 20 by the fixed roller 42 and the pressing roller 43.
Since the sliding substrate 44 is engaged with the second guide rail 21 while holding the substrate 1, the sliding substrate 44 can be moved even if the positional relationship between the second guide rail 21 and the pair of rollers 42, 43 is not strict. becomes. That is, the first
As long as the guide rail 20 and the second guide rail 21 are on the same plane, even if they are not completely parallel, the sliding movement of the sliding board 44 will not be affected much. Therefore, setting of the guide rails 20, 21, etc. becomes extremely easy.

Further, the pressure roller 43 is attached to a pressure roller mounting plate 53, and by removing the pressure roller mounting plate 53 from the roller mounting plate 51, the pair of rollers 42, 43 can be freely released from the second guide rail 21, and the pair of rollers 42, 43 can be slid. Since the substrate 44 and the optical section 5 attached thereto can be rotated around the first guide rail 20, maintenance and inspection of the portion arranged on the lower side of the optical section substrate 46 can be easily performed. I can do it.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment and can be further modified. For example, the laser light source 6
may be used as a laser diode. In addition, the optical system from the laser light source 6 to the disk 1 and the disk 1
The optical system from the beam detector to the beam detector may be modified in various ways. It is also applicable to recording devices.
Further, the sliding substrate 44 may be moved by providing a threaded hole in the sliding substrate 44 and screwing a threaded rod thereinto, and rotating the threaded rod with a feed motor. Further, the springs 31 and 57 may be tension coil springs. Further, the wire 22 may be a driving band (belt) such as a linear object or a belt-like object made of synthetic resin or the like. The present invention is also applicable to a disk recording/reproducing apparatus in which the tracks on the disk 1 are concentric and the optical section 5 is intermittently sent in the radial direction of the disk.

[Brief explanation of the drawing]

FIG. 1 is an explanatory front view of a disk playback device according to an embodiment of the present invention, FIG. 2 is an explanatory plan view of the disk, FIG. 3 is an explanatory cross-sectional view of the disk, and FIG. 4 is the same as that shown in FIG. 5th plan view specifically showing the device of
6 is an enlarged front view of the drive pulley portion of FIG. 4, FIG. 6 is an enlarged front view of the roller portion of FIG. 4, and FIG. 7 is a plan view of the optical portion of FIG. 4. In the symbols used in the drawings, 1 is a disk, 2 is a disk motor, 3 is a turntable, 4 is a clamper, 5 is an optical section, 6 is a laser light source, 13 is a condenser lens, and 20 is a first 21 is a second guide rail, 22 is a wire,
24 is the first pulley, 25 is the second pulley, 26
is a radial feed drive unit, 27 is a feed motor, 28
29 is a drive pulley, 29 is a lever for applying tension, 31 is a spring, 38 is a disk drive unit, 39 is a drive unit board, 42 is a fixed roller, 43 is a pressure roller, 44
is a sliding substrate, 47 is a focus actuator, 5
1 is a roller mounting plate, and 54 is a rotating plate.

Claims (1)

[Claims for Utility Model Registration] A disk driving section for holding a recording or reproducing disk and rotating the disk; an optical section for projecting a recording or reproducing beam onto the disk; An optical disk recording and reproducing device comprising: a guide section that guides an optical section in the radial direction of the disk; and a radial feed drive section that moves the optical section guided by the guide section in the radial direction of the disk. In this, the optical section includes at least a light source, an optical system for projecting a light beam emitted from the light source onto the disk and guiding a reflected beam obtained from the disk to its detection position, and the reflecting beam. a beam detector for detecting the beam, and the light source, the optical system, and the beam detector are attached to the same optical part substrate, and the optical part is assembled separately from the guide part. an optical disk recording device, wherein the guide section comprises a guide rail and a sliding board guided by the guide rail, and the optical part board is mounted at a predetermined position on the sliding board. playback device.