JP4048866B2 - Optical pickup device, optical information recording and / or reproducing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical pickup device that records (writes) and / or reproduces (reads) information signals on an optical disk such as an optical disk or a magneto-optical disk, and optical information recording and / or mounting the optical pickup apparatus. The present invention relates to a playback device.
[0002]
[Prior art]
As an optical information recording and / or reproducing apparatus that records and / or reproduces an information signal with respect to an optical disk by mounting an optical pickup apparatus and the optical pickup apparatus, those shown in FIGS. 14 and 15 are known.
[0003]
The optical pickup device 101 includes an objective lens 102 that condenses laser light emitted from a light source and irradiates the signal recording surface of an optical disk, an actuator 103 that performs focusing control and tracking control of the objective lens 102, and A cover 104 that covers the actuator 103 and an optical unit (not shown) are provided.
[0004]
Then, the laser light emitted from the laser of the optical unit is irradiated onto the signal recording surface of the optical disk through the objective lens 102, and the reflected laser light is incident on the detector of the optical unit to cause a focus error. Signals, tracking error signals, and information signals are detected.
[0005]
The cover 104 covers the actuator 103 to protect it from dust and the like.
[0006]
The cover 104 includes a cover main body 106 having an opening 105 at a position facing the front Symbol pair objective lens 102, a cylindrical side wall portion 107 provided on the peripheral portion of the cover main body 106, in construction Has been.
[0007]
As shown in FIG. 15, the cover 104 has an engagement portion 111 provided on the inner peripheral surface of the cylindrical side wall 107 by fitting the cylindrical side wall 107 to the outer peripheral side of the actuator 103. It is attached by engaging with an engaged portion 112 provided on the actuator 103 side.
[0008]
Further, as shown in FIG. 14, the optical information recording and / or reproducing device 201 includes the optical pickup device 101, a disk rotation driving device 202 that rotationally drives the optical disk, and the optical pickup device 101 as the optical disk. And a drive mechanism 203 that moves in the radial direction.
[0009]
[Problems to be solved by the invention]
Incidentally, in the conventional optical pickup device 101 and the optical information recording and / or reproducing device 201 provided with the optical pickup device 101, the cover 104 is opened at a portion facing the objective lens 102 as described above. A cover main body portion 106 provided with a portion 105 and a cylindrical side wall portion 107 provided at the peripheral edge of the cover main body portion 106, and the cylindrical side wall portion 107 is connected to the outer periphery of the actuator 103. The cover 104 is attached and detached by engaging an engaging portion 111 provided on the inner peripheral surface of the cylindrical side wall portion 107 with an engaged portion 112 provided on the actuator 103 side. Since it was configured to be freely mounted, there were the following problems.
(1) As shown in FIG. 17, when the inner diameter D1 of the cylindrical side wall portion 107 is smaller than the outer diameter D2 of the engaged portion 112, the cylindrical side wall portion 107 is moved to the engaged portion. 112 cannot be fitted. Conversely, when the inner diameter D1 of the cylindrical side wall portion 107 is too larger than the outer diameter D2 of the engaged portion 112, the engaging portion 111 provided on the inner peripheral surface of the cylindrical side wall portion 107 is provided. It becomes impossible to engage with the engaged portion 112.
(2) As shown in FIG. 16, a gap G is inevitably generated between the engaging portion 111 provided on the inner peripheral surface of the cylindrical side wall portion 107 and the engaged portion 112 ( (The gap G is indispensable for absorbing the positional accuracy error of the engaging portion 111 and the engaged portion 112 and engaging the engaging portion 111 with the engaged portion 112). The cover 104 is loose.
[0010]
It is an object of the present invention to provide an optical pickup device and an optical information recording and / or reproducing device that solves the above-mentioned conventional problems, eliminates the backlash of the cover, and can reliably and easily attach the cover to the actuator side. It was made as.
[0011]
[Means for Solving the Problems]
The present invention includes an objective lens that condenses laser light emitted from a light source and irradiates the signal recording surface of an optical disk, an actuator that performs focusing control and tracking control of the objective lens, a cover that covers the actuator, In an optical pickup device equipped with the optical pickup device and an optical information recording and / or reproducing device equipped with the optical pickup device,
The cover is composed of a cover main body portion provided with an opening in the facing portion of the objective lens, and a plurality of leg portions provided on the side of the cover main body portion,
In the leg portion, an engaged portion that engages with a cover engaging portion provided on the actuator side with the cover body portion covering the actuator is provided,
The cover body is provided with an urging portion that presses the upper surface of the actuator in a state where the cover is attached, and the engagement is provided on the leg portion by a reaction force when the urging portion presses the upper surface of the actuator. The cover and the cover engaging portion provided on the actuator side were brought into contact with each other to prevent the cover from rattling.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an optical pickup device of the present invention and an optical information recording and / or reproducing device equipped with the optical pickup device will be described with reference to the drawings.
[0013]
As shown in FIGS. 1 and 2, the optical pickup device 1 includes an objective lens 2 that condenses laser light emitted from a light source and irradiates the signal recording surface of an optical disk, focusing control of the objective lens 2, and An actuator 3 that performs tracking control and a cover 4 that covers the actuator 3 are provided.
[0014]
As shown in FIGS. 3 and 4, the objective lens 2 includes a lens main body 21, a frame 22 provided on the outer periphery of the lens main body 21, and a pair of heat provided on the frame 22. Boss portions 23 and 24 for caulking and coupling are provided. The objective lens 2 is heat caulked and coupled to a bobbin as a lens holder as described later by using the pair of heat caulking coupling boss portions 23 and 24.
The objective lens 21 is integrally formed of a synthetic resin such as polyolefin.
[0015]
As shown in FIG. 1, the actuator 3 has a bobbin 31 as the lens holder (movable part) and one end attached to both the left and right sides of the bobbin 31 to control the objective lens 2 in the focus control direction and tracking control. A pair of left and right linear support members 32 that are movably supported in the direction, and a fixing portion 33 that supports the other end of these support members 32 are provided.
[0016]
As shown in FIGS. 5 to 7, the bobbin 31 is formed in a substantially hexagonal frame shape and has a lens main body insertion hole 34 at the center, and is formed on both sides of the lens main body insertion hole 34. A pair of boss portion insertion holes 35 and 36 are provided.
[0017]
As shown in FIGS. 8 and 9, the bobbin 31 inserts the lens body 21 of the objective lens 2 into the lens body insertion hole 34, and inserts the objective lens 2 into the boss insertion holes 35 and 36. The objective lens 2 is attached and supported by inserting the boss portions 23 and 24 for caulking and inserting the tips of the boss portions 23 and 24 by heat caulking. Reference numerals 23a and 24a denote enlarged diameter portions formed by heat caulking.
[0018]
5-7, the bobbin 31 is provided with tracking control coil winding portions 37 ... 37 at four locations on the outer peripheral side thereof, and the tracking control coil winding portions 37 ... 37 are provided. Focus coil winding portions 38... 38 are provided outside.
[0019]
Then, as shown in FIG. 10, the tracking control coils 39 are wound around the four tracking control coil winding portions 37... 37, respectively, and the tracking windings wound around the four tracking control coil winding portions 37. A focus control coil 40 is wound around the focus coil winding portion 38... 38 so as to surround the control coil 39.
[0020]
A pair of terminal boards 41 are arranged outside the focus control coil 40, and one end of each of the pair of linear support members 32 is connected to each of the terminal boards 41.
[0021]
The linear support member 32 is formed of a metal wire having springiness and conductivity, such as phosphor bronze and beryllium copper.
[0022]
The linear support member 32 having one end attached to the terminal plate 41 extends in a direction perpendicular to the optical axis of the objective lens 2 and the other end is attached to the fixing portion 33.
[0023]
The fixed portion 33 includes a printed circuit board 42 on one side, and the other end of the linear support member 32 is connected to the printed circuit board 42 by soldering or the like.
[0024]
The fixing portion 33 is disposed on a base portion 43 made of synthetic resin. On the base portion 43, a pair of magnets 44 and 45 are directly attached with an adhesive or the like so as to sandwich the bobbin 31 around which the focus control coil 40 and the tracking control coil 39 are wound.
[0025]
Further, first and second side wall portions 46 and 47 are provided on the base portion 43 so as to surround the bobbin 31. As shown in FIG. 1, the first side wall portion 46 includes first and second cover engaging portions 48 a and 48 b for engaging a cover 4, which will be described in detail below, on the outer surface. The second side wall 47 includes third and fourth cover engaging portions 48c and 48d on the outer surface.
[0026]
The cover 4 includes a cover main body (upper surface) 51 having an opening 50 in a portion facing the objective lens 2, and first and second legs provided on one side of the cover main body 51. Parts 52 and 53, and third and fourth legs 54 and 55 provided on the other side of the cover body 51, and the first and second legs 52 and 53, respectively. The first side wall portion 46 and the second side wall portion 47 are sandwiched between the third and fourth leg portions 54 and 55.
[0027]
The first to fourth leg portions 52 to 55 include first to fourth engaged portions 56a to 56d that engage with the first to fourth cover engaging portions 48a to 48d, respectively. . The cover body 51 includes first and second urging portions 57 and 58 that press the upper surfaces of the pair of magnets 44 and 45 on both sides of the opening 50.
[0028]
The cover 4 cuts and raises the first to fourth leg portions 52 to 55 and the first and second urging portions 57 and 58 after punching a metal plate such as a stainless steel thin plate into a predetermined shape ( Or is integrally molded with a synthetic resin.
[0029]
The cover 4 is configured as described above, and the first and second legs 52 and 53 and the third and fourth legs 54 and 55 are disposed between the first and second legs. If the side wall portions 46 and 47 are inserted, as described above, the engaged portions 56a to 56d provided in the first to fourth leg portions 52 to 55 and the first to fourth cover engaging portions. 48a to 48d are engaged with each other, and urging portions 57 and 58 provided on the cover main body 51 press the upper surfaces of the pair of magnets 44 and 45.
[0030]
Therefore, as shown in FIG. 11, the cover 4 is against the first and second side wall portions 46 and 47 by a reaction force when pressing the magnets 44 and 45 of the urging portions 57 and 58. Pushed up in the direction of arrow A, the end portions of the first to fourth engaged portions 56a to 56d are crimped to the lower ends of the first to fourth cover engaging portions 48a to 48d, and The cover 4 can be securely attached to the first and second side wall portions 46 and 47 without rattling.
[0031]
As shown in FIG. 1, the base portion 43 includes a guide shaft insertion hole 43a on one side and a guide piece 43b on the other side. And as shown in FIG. 12, the said base part 43 is attached to the chassis 61 so that a slide is possible.
[0032]
The chassis 61 includes a rectangular opening 62 at a substantially central portion thereof, and includes a base guide shaft 63 along a side of one long side of the opening 62, and the other of the openings 62. A guide piece support 64 is provided along the side of the long piece.
[0033]
The chassis 61 inserts the base portion guide shaft 63 into the guide shaft insertion hole 43a, and supports the guide piece 43b with the guide piece support portion 64, whereby the base portion 43 and the optical pickup device 1 are The opening 62 is slidably supported.
[0034]
The base portion 43 slides along the base portion guide shaft 63 and the guide piece support portion 64 by the drive mechanism 71.
[0035]
The drive mechanism 71 includes a motor 72 and a rack and pinion 73 or a lead screw that changes the rotation of the motor 72 into a linear movement of the base portion 43.
[0036]
A disk rotation drive mechanism 81 is disposed on the frame side on one short piece side of the rectangular opening 62 of the chassis 61. The disk rotation drive mechanism 81 includes a turntable 82 and a motor 83 that rotates the turntable 82, and the optical disk chucked on the turntable 82 is rotated by the motor 83. Yes.
[0037]
As shown in FIG. 13, an optical unit 91 is disposed below the objective lens 2. The optical unit 91 includes a semiconductor laser 92 serving as a light source for emitting laser light, a diffraction grating (grating) 93, a semi-transmissive mirror (beam splitter plate) 94, a photodetector 95 including a photodiode, and the like. ing. These optical components are arranged in a predetermined positional relationship in a housing 97 having a predetermined optical path 96 so that the laser beam can freely pass therethrough.
[0038]
The laser light emitted from the semiconductor laser 92 passes through the diffraction grating 93, is reflected by the semi-transmissive mirror 94, is bent by 90 °, and enters the objective lens 2. The laser light incident on the objective lens 2 is irradiated on the disk substrate side of the optical disk D, passes through the disk substrate, and is condensed on the signal recording surface.
[0039]
The laser beam condensed on the signal recording surface of the optical disc D is reflected after the intensity is modulated in accordance with the information signal recorded on the signal recording surface. The laser beam reflected by the signal recording surface is transmitted through the objective lens 2 and the semi-transmissive mirror 94 and is collected on the light receiving surface of the photodetector 95.
[0040]
The return laser light passes through a semi-transmissive mirror 94 disposed at an angle of 45 ° with respect to the optical axis, thereby causing astigmatism. Each light beam is received by the photodetector 95. The photodetector 95 has a light receiving surface divided into a plurality of portions, and outputs a light detection signal of a level corresponding to the received light amount independently for each portion. By performing arithmetic processing between a plurality of light detection signals output from the light detector 95, a reproduction signal (RF signal) of information read from the optical disk D, a focus error signal, and a tracking error signal are obtained. be able to. Then, based on the reproduction signal, a reproduction operation of information recorded on the optical disc D is performed.
[0041]
In the embodiment shown in the drawings, the so-called yokeless magnet direct attachment type in which the magnets 44 and 45 are directly attached to the base portion 43 made of synthetic resin with an adhesive or the like without using a metal yoke for the actuator 3. However, this is because the magnets 44 and 45 are attached to the base portion 43 made of synthetic resin with an adhesive or the like because the yokeless type actuator directly attaches the magnets 44 and 45 to the base portion 43 made of synthetic resin. 43 is easy to peel off. Therefore, the upper surface of the magnets 44 and 45 is pressed by the urging portions 57 and 58 so as to prevent the magnets 44 and 45 from being peeled off. However, the magnets 44 and 45 are peeled off by using a yoke. Even in the case of an actuator using a yoke that is less likely to occur, the biasing portions 57 and 58 have an effect of preventing the cover 4 from rattling. Further, the number of leg portions, cover engaging portions, and engaged portions is arbitrarily set according to the size of the cover.
[0042]
【The invention's effect】
The optical disk apparatus of the present invention has the following effects.
(1) In the optical pickup device according to the first aspect, the backlash of the cover can be prevented by the reaction force of the urging portion generated when the cover is attached. And generation | occurrence | production of the abnormal noise by the said backlash and the fall of a cover can be prevented.
( 2 ) The optical pickup device of claim 2 can more reliably prevent the cover from rattling by attracting the cover or the urging portion with a magnet.
( 3 ) In the optical pickup device according to the third aspect , since the urging portion is formed by cutting and raising a part of the cover, an increase in the number of parts due to the provision of the urging portion can be prevented.
(4) In the optical pickup device according to the fourth aspect, since the cover is made of synthetic resin, it is possible to prevent the magnetic field distribution from changing as in the case where the cover is made of metal such as stainless steel.
( 5 ) In the optical pickup device according to the fifth aspect , the magnet can be prevented from peeling from the base portion by compensating for the disadvantage that the magnet is easily peeled from the base portion by pressing the upper surface of the magnet with the urging portion.
( 6 ) The optical information recording and / or reproducing apparatus according to claim 6 prevents the cover of the optical pickup device from rattling, and prevents the generation of abnormal noise and the removal of the cover when the optical pickup device moves. In addition, the function of the optical pickup device can be fully exhibited.
[Brief description of the drawings]
FIG. 1 is a perspective view of an optical pickup device (with a cover removed).
FIG. 2 is a perspective view of the optical pickup device (with a cover attached).
FIG. 3 is a plan view of an objective lens.
FIG. 4 is a plan view of an objective lens.
FIG. 5 is a plan view of a bobbin.
FIG. 6 is a bottom view of the bobbin.
7 is a cross-sectional view taken along line AA in FIG.
FIG. 8 is a cross-sectional view of a state where a boss portion of an objective lens is inserted into a boss portion insertion hole of a bobbin.
FIG. 9 is a cross-sectional view showing a state in which heat caulking is applied to the tip of the boss portion of the objective lens.
FIG. 10 is a plan view of a main part.
FIG. 11 is a cross-sectional view of a main part.
FIG. 12 is a perspective view of an optical information recording and / or reproducing apparatus.
FIG. 13 is an explanatory diagram of an optical unit.
FIG. 14 is a perspective view of a conventional optical pickup device (with a cover removed).
FIG. 15 is a perspective view of a conventional optical pickup device (with a cover attached).
16 is a cross-sectional view taken along line AA in FIG.
FIG. 17 is a cross-sectional view showing a state where a cover is separated.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Optical pick-up apparatus, 2 ... Objective lens, 3 ... Actuator, 4 ... Cover, 43 ... Base part, 44, 45 ... Magnet, 48a-48d ... Cover engaging part, 51 ... Cover main-body part, 53-55 ... 1st DESCRIPTION OF SYMBOLS 1st-4th leg part, 56a-56d ... to-be-engaged part, 57, 58 ... biasing part, 71 ... drive mechanism, 81 ... disc rotation drive mechanism, 201 ... optical information recording and / or reproducing | regenerating apparatus.

Claims (6)

An objective lens that condenses the laser light emitted from the light source and irradiates the signal recording surface of the optical disk;
An actuator for performing focusing control and tracking control of the objective lens;
A cover covering the actuator;
In an optical pickup device comprising:
The cover includes a cover main body portion provided with an opening in a facing portion of the objective lens, and a plurality of legs provided on a side portion of the cover main body portion,
The leg portion includes an engaged portion that engages with a cover engaging portion provided on the actuator side in a state where the actuator is covered with the cover body portion,
The said cover body portion provided with the biasing unit for pressing the upper surface of the actuator in a state of attaching the cover Bei example, the leg reaction force when pressing the upper surface of the actuator urging portion An optical pickup device , wherein the engaging portion is brought into contact with a cover engaging portion provided on the actuator side . The cover main body is formed of a metal plate.
The optical pickup device according to claim 1. The optical pickup device according to claim 2 , wherein the urging portion is formed by cutting and raising a part of the cover main body portion. The cover body is made of synthetic resin.
The optical pickup device according to claim 1. The magnet constituting the actuator is directly attached on a base portion provided with the actuator, and the upper surface thereof is pressed against the base portion side by the urging portion. Optical pickup device. An objective lens that condenses the laser light emitted from the light source and irradiates the signal recording surface of the optical disc, an actuator that performs focusing control and tracking control of the objective lens, and an optical pickup device that includes a cover that covers the actuator;
A drive mechanism for moving the optical pickup device in the radial direction of the optical disk;
A disk rotation drive mechanism for rotating the optical disk,
The cover includes a cover main body portion provided with an opening in a facing portion of the objective lens, and a plurality of legs provided on a side portion of the cover main body portion,
The leg portion includes an engaged portion that engages with a cover engaging portion provided on the actuator side in a state where the actuator is covered with the cover body portion,
The cover main body, e Bei a biasing unit for pressing the upper surface of the magnet that constitutes the actuator in a state of attaching the cover, the leg reaction force when pressing the upper surface of the actuator urging portion An optical information recording and / or reproducing apparatus , wherein an engaged portion provided on the actuator is brought into contact with a cover engaging portion provided on the actuator side .

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