JP2002042351A - Optical disk drive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To adjust the quantity of an off-center, so as to always arrange a spot diameter direction moving locus of an optical disk to lie on one diameter line on the optical disk. SOLUTION: This optical disk driving device 1A is provided with a first base 5 having a turntable 2, a second base 6 having an optical pickup 10 attached freely movably, and a pair of tilt supporting shafts 15 and 16 disposed on a straight line substantially orthogonal to the moving direction of an optical disk D sandwiching an optical pickup 10, and a tilt correction means 50 for swinging the whole second base 6 around the pair of the tilt support shafts 15 and 16 in a height direction with respect to the first base 5, so as to always make a laser beam incident roughly vertically to the radial direction of the signal surface of the optical disk D. In this case, the other tilt-supporting shaft 16 is displaced in the diameter direction of the optical disk D so as to make the entire second base 6 turn in a plane substantially parallel to the optical disk D.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk drive provided with a radial tilt adjusting mechanism so that a laser beam emitted from an optical pickup always hits the signal surface of the optical disk almost perpendicularly to the radial direction.
The present invention relates to an optical disk drive device provided with an off-center amount adjusting means for adjusting an off-center amount such that a radial movement locus of a spot on an optical disk irradiated with a laser beam is always on one diameter line passing through the center of the optical disk.

[0002]

2. Description of the Related Art In general, a disc-shaped optical disk can record and reproduce information signals such as video information, audio information, and computer data on a spiral or concentric track at a high density, and moreover, can reproduce a desired track at a high speed. It is often used because it can be accessed.

In an optical disk drive for recording and reproducing data using an optical disk as described above, an optical pickup device is movably provided in a radial direction of the optical disk, and a laser beam emitted from an objective lens in the optical pickup device is provided. An optical pickup device provided with an off-center amount adjusting means for irradiating an optical disc and adjusting the trajectory of a spot on the optical disc irradiated with the laser beam in the radial direction so as to always coincide with one diameter line passing through the center of the optical disc. A proposal regarding a guide device is disclosed in Japanese Patent Application Laid-Open No. 04-109433.

FIGS. 15A and 15B are a perspective view and a plan view, respectively, for explaining a guide device of a conventional optical pickup device.
0 is disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 04-109433, and will be briefly described here.

As shown in FIGS. 15 (a) and 15 (b), a guide device 100 of a conventional optical pickup device uses a laser beam emitted from an objective lens 112a in an optical pickup device 112 in a tangential direction (tangent direction) of an optical disk. The configuration is such that the off-center which occurs when the tilt adjustment with respect to the neutral direction and the track direction is performed is eliminated.

That is, a spindle motor 102 is attached to the chassis 101 from the back side, and a shaft 102a of the spindle motor 102 is
The disk table 103 fixed to a is rotatable.

On the other hand, an optical pickup device support plate 111 is provided on the chassis 101 so as to be movable in a direction parallel to the chassis 101.

The optical pickup device support plate 111
In the opening 111a of the optical pickup device 112,
Are mounted movably in the radial direction (the direction of arrow K) of the optical disk (not shown).

The optical pickup device support plate 111
The support shaft 113 protruding laterally from one side near the spindle motor 102 is supported by a V-groove of a support piece 114 provided on the chassis 101. Further, the optical pickup device support plate 111 is compressed by a compression coil spring 114 disposed between a side portion facing the support shaft 113 and a spring support piece 101a protruding from the chassis 101, as indicated by an arrow G in FIG. Biased in the direction.

A long guide shaft 115 is inserted into a support hole 112b formed on the front side of the optical pickup device 112, and the optical pickup device 112 is slidable with respect to the guide shaft 115. And both ends of the guide shaft 115 are connected to the optical pickup device support plate 11.
A first abutting member 111b protruding left and right on
Positioning is performed by contacting the side of 111c. On the other hand, a support groove 112c formed on the back side of the optical pickup device 112 is engaged with the edge of the opening 111a of the optical pickup device support plate 111.

A guide shaft 115 for guiding the optical pickup device 112 in the radial direction of the optical disk is provided with a slit 115a at the left end in the drawing, which can be rotated and adjusted by a driver or the like. The first cam bodies 116 and 117 are attached near both ends of the optical pickup device 111 and are arranged so as not to come into contact with the side portions of the first abutting members 111b and 111c of the optical pickup device support plate 111. The first cams 116 and 117 are formed in a cylindrical shape eccentric with respect to the guide shaft 115, and the eccentric directions are equal to each other.

A second cam body 118 is mounted on the right side of the left cam body 116 mounted on the guide shaft 115. Although the second cam body 118 is also formed in a cylindrical shape eccentric with respect to the guide shaft 115, the direction of eccentricity with respect to the guide shaft 115 is the first cam body 116,1.
The direction of eccentricity is different from the direction of 17 eccentricity. The second cam body 118 is in contact with a second abutting member 101b projecting from the chassis 101. At this time, the contact between the second cam body 118 and the second butting member 101b is maintained by the compression coil spring 114.

The two ends of the guide shaft 115 are supported by leaf springs 119 and 120 to support the optical pickup device support plate 111.
It is pressed against the side of the first butting members 111b and 111c projecting upward.

Next, the operation of the guide device 100 of the conventional optical pickup device having the above configuration will be described.

First, the slotting portion 115 of the guide shaft 115
A screwdriver is inserted into a, and the shaft 115 is rotated. Then, the height of the guide shaft 115 with respect to the optical pickup support plate 111 can be changed by the action of the first cam bodies 116 and 117, and the optical pickup device 112 is eccentric about the vicinity of the support groove 112c. Since the guide shaft 115 moves up and down substantially in parallel with the signal surface of the optical disk in accordance with the diameters of 116 and 117, tangential tilt correction can be performed. However, at this time, due to the eccentricity of the first cam bodies 116 and 117, the radial movement locus of the spot due to the beam emitted from the objective lens 112a in the optical pickup device 112 to the optical disk is one straight line passing through the center of the optical disk. An off-center amount deviating from above occurs. Therefore, a second cam body 118 is provided which can cancel the deviation of the radial movement locus of the spot when adjusting the tangential tilt. The second cam body 118 is the first cam body 118 as described above.
The cams 116 and 117 have different eccentric angles, and this change is for canceling the deviation of the radial movement locus of the spot. Therefore, when the guide shaft 115 is rotated, the second cam body 118 is also rotated at the same time, and the off-center amount can be adjusted while performing tangential tilt.

[0016]

According to the guide device 100 of the above-described conventional optical pickup device, the guide shaft 115 for guiding the optical pickup device 112 in the radial direction of the optical disk is rotated, thereby allowing the optical disk device to rotate. An optical disc drive capable of performing a radial tilt correction in a radial direction (radial direction) of an optical disc, while being able to simultaneously adjust an off-center amount while performing a tangential tilt in a tangential direction (tangential, track direction) of the optical disc It is difficult to apply to It is for the following reasons.

[0017] It is difficult to accurately mount cam bodies having the same eccentric phase near both ends of a guide shaft that guides the optical pickup device in the radial direction of the optical disk.

[0018] In the future recording type optical disk drive, the optical pickup device tends to be larger,
There is not enough space to attach the cam.

In an optical disk drive having the above configuration, a three-beam system is often employed for tracking servo. In the three-beam system, there are two sub-beams on both sides in the track direction of a main beam for reading data on an optical disk, and it is necessary to adjust the output of the two sub-beams to be always equal. For this reason, in the three-beam system, when an optical pickup device (hereinafter, referred to as an optical pickup) seeks, a spot on the optical disk must always accurately trace on one diameter of the optical disk. It is necessary to adjust the off-center amount. This adjustment is called off-center amount adjustment. Conventionally, the amount of off-center adjustment has been adjusted by finely adjusting a spindle motor to which a turntable is attached or by finely adjusting the position of a guide shaft supporting an optical pickup in a direction perpendicular to the axis. However, in these methods, it was difficult to actually adjust the optical disk while rotating the optical disk while watching the output signal from the optical pickup. In addition, there has been considerable difficulty in enabling the position of a spindle motor, which should be firmly fixed, to be adjusted.
In addition, fine adjustment of the guide shaft for guiding the optical pickup needs to be performed so as not to cause displacement in the vertical direction, which is difficult. The present invention is to solve the problems of the conventional adjusting method.

[0020]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a first invention is directed to a first base on which a turntable for rotating an optical disk is mounted, and an optical pickup comprising the optical disk. A second base having a pair of tilt support shafts attached to the optical pickup on a straight line substantially perpendicular to a moving direction of the optical disc on the inner peripheral side of the optical disc, while being movably mounted in a radial direction of the optical disc; In order for the laser beam emitted from the optical pickup to be always incident substantially perpendicularly to the radial direction of the signal surface of the optical disc, the entire second base is centered around the pair of tilt support shafts with respect to the first base. An optical disc drive device comprising: a radial tilt correcting means for swinging in a height direction. As a fulcrum square tilt support shaft side of,
By displacing the other tilt support shaft in the radial direction of the optical disc so as to rotate the entire second base in a plane substantially parallel to the optical disc, the diameter of the spot on the optical disc irradiated with the laser beam is reduced. An optical disk drive device comprising an off-center amount adjusting means for adjusting an off-center amount so that a directional movement locus is always on one diameter line passing through the center of the optical disk.

According to a second aspect of the present invention, in the optical disk drive according to the first aspect, the off-center amount adjusting means includes a pair of tilt support members on the first base corresponding to the pair of tilt support shafts. A bearing arm is rotatably mounted to support the pair of tilt support shafts on the pair of tilt support bearing arms, and the one tilt support bearing arm supporting one tilt support shaft to the second base. An optical disc drive, wherein the tilt support bearing arm supports the other tilt support shaft and presses the other tilt support bearing arm in a direction in which the off-center amount decreases.

According to a third aspect of the present invention, in the optical disk drive of the first aspect, the off-center amount adjusting means forms a pivot as a convex conical surface at a tip of the pair of tilt support shafts, and Forming a pivot bearing having a concave conical surface on a pair of bearing blocks to be fitted in opposition to the pivots of the pair of tilt support shafts,
One of the pair of bearing blocks is fixed on the first base in a state where the one bearing block is fitted to the tilt support shaft opposed thereto, and is configured to be a rotation fulcrum of the second base. The other bearing block is rotatably mounted on the first base in a state where the bearing block is fitted to the tilt support shaft opposed thereto, and the other bearing block is pressed in a direction in which the off-center amount decreases. Optical disk drive device.

According to a fourth aspect of the present invention, in the optical disk drive according to the first or second aspect, the adjustment of the off-center amount by the off-center amount adjusting means is performed outside a diameter of the optical disk. An optical disk drive characterized in that it is configured.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of an optical disk drive according to the present invention will be described below in detail in the order of <first embodiment> and <second embodiment> with reference to FIGS.

<First Embodiment> FIG. 1 is a perspective view of an optical disk drive according to a first embodiment of the present invention, FIG. 2 is a plan view of the optical disk drive of the first embodiment according to the present invention, and FIG. FIG. 1 is an exploded perspective view showing an optical disk driving device according to a first embodiment of the present invention in an exploded manner.

First, a schematic configuration of an optical disk drive 1A according to a first embodiment of the present invention will be described with reference to FIGS.

After the optical disk D is mounted on the turntable 2, the disk clamp 3
, And is rotated by the spindle motor 4 in a predetermined direction. The spindle motor 4 is fixed to the left end portion in the longitudinal direction of a first base 5 formed flat using a sheet metal material.

On the other hand, above the first base 5, the optical disk D
Means that the second base 6 is positioned at an intermediate position in height by a radial tilt correcting means 50 to be described later.
The first base 5 is attached to the first base 5 so as to be swingable in the height direction.

The above-mentioned second base 6 is formed by bending a "U-shape" using a sheet metal material. The length of the second base 6 in the longitudinal direction is shorter than the length of the first base 5 in the longitudinal direction. Is set. At this time, by setting the right end of the second base 6 in the longitudinal direction to be short, a radial tilt correction unit 50 described later can be attached to the right end of the first base 5 in the longitudinal direction.

The upper surface 6a of the second base 6 has the first
An escape hole 6a1 facing the turntable 2 attached to the base 5 and an optical pickup 10 described later is largely opened.

On the back side of the upper surface 6a of the second base 6, a long guide shaft 7 and a long guide rail 8 are opposed to each other with an interval therebetween in the radial direction of the optical disc D (arrow K).
) Are extended substantially parallel to each other. An optical pickup support 9 and an optical pickup 10 mounted on the optical pickup support 9 are integrated between the long guide shaft 7 and the long guide rail 8 to form the long guide shaft 7 and It is provided movably in the radial direction of the optical disk D while being guided by the long guide rail 8. At this time, a driving mechanism for moving the optical pickup support 9 and the optical pickup 10 is provided by the side surface 6 of the second base 6.
b, a gear 12 attached to the shaft of the motor 11, a rack 14 attached to the optical pickup support 9 (only shown in FIG. 2), and an intermediate gear 13 meshed with the gear 12 (only FIG. 2). (Shown).
The rotation of the motor 11 is controlled by the gear 12, the intermediate gear 13,
By converting the movement into a linear movement via the rack 14, the optical pickup support 9 and the optical pickup 10 are integrally movable in the radial direction of the optical disk D (the direction of arrow K).

A pair of tilt support shafts 15 and 16 are provided on a side surface 6b bent forward from the upper surface 6a of the second base 6 and a rear side surface 6c opposed to the side surface 6b with the optical pickup 10 interposed therebetween. The pair of tilt support shafts 15 and 16 are attached along a straight line substantially orthogonal to the moving direction of the optical pickup 10.
b, 6c. At this time, the straight line on which the pair of tilt support shafts 15 and 16 is attached is set at a location where the signal surface on the inner peripheral side of the optical disk D intersects with the diameter near the lead-in.

On the other hand, on the first base 5, a pair of tilt support bearings 20 and 30 are provided on the side surfaces 6b and 6c of the second base 6.
The pair of tilt support shafts 15 and 16 are mounted corresponding to the pair of tilt support shafts 15 and 16. The pair of tilt support shafts 15 and 16 are supported by the pair of tilt support bearing portions 20 and 30. Then, the above-mentioned pair of tilt support shafts 15, 1
6 and a pair of tilt support bearing portions 20 and 30 constitute an off-center amount adjusting means which is a main part of the first embodiment, which will be described later in detail.

On the right end side of the first base 5 and the right end side of the second base 6, the entire second base 6 is swung with respect to the first base 5 in the height direction with respect to the first base 5. A moving radial tilt correcting means 50 is provided.

The radial tilt correction means 50 includes a first
A worm 52 is fixed to a shaft of a tilt motor 51 mounted on the base 5, and a cam gear 53 meshing with the worm 52 is supported rotatably about a shaft 54 implanted on the first base 5. ing.

On the other hand, a projecting piece 6a2 is formed in a triangular shape from the right end of the upper surface 6a of the second base 6 so as to face the cam gear 53, and a pin 55 fixed to the tip of the projecting piece 6a2 Abuts on the cam surface 53a. At this time, the cam surface 53a of the cam gear 53 is formed as an inclined cylindrical tapered surface that changes continuously in the height direction when the first base 5 is at the reference height position.

On the first base 5, the tilt motor 51 and the cam gear 53 are sandwiched between the near side and the far side in the drawing.
Leaf spring support blocks 56 and 57 are attached.
Further, leaf springs 58, 59 extend on the upper surfaces of the leaf spring support blocks 56, 57 toward the upper surface 6a of the second base 6, and the leaf springs 58, 59 lower the second base 6 on the first base. Each is attached so as to urge it to the fifth side. In addition, the leaf springs 58 and 59 are connected to the upper surface 6 of the second base 6.
When the second base 6 is rotated in a plane substantially parallel to the first base 5 and the optical disc D as described later in a state in which the second base 6 is pressed downward, the upper base 6a of the second base 6 Since the ends of the springs 58 and 59 are slid, no trouble occurs.

Then, when the tilt motor 51 starts and the cam gear 53 rotates via the worm 52, the cam surface 53a of the cam gear 53 changes in the height direction, and the pin fixed to the projecting piece 6a2 of the second base 6 is formed. 55 is a leaf spring 58,
Since the second base 6 swings in the height direction (vertical direction) with respect to the first base 5 about the pair of tilt support shafts 15 and 16 because the cam surface 53a follows the cam surface 53a with the urging force of 59. The laser beam emitted from the optical pickup 9 attached to the second base 6 can always be applied substantially perpendicularly to the radial direction of the signal surface of the optical disc D.

Next, the configuration of the off-center amount adjusting means, which is a main part of the first embodiment, will be described in detail with reference to FIGS.

FIG. 4 is an exploded perspective view showing an enlarged and disassembled view of the tilt support shaft and the tilt support bearing on the front side, which constitute a part of the off-center amount adjusting means which is a main part of the first embodiment.
FIGS. 5A and 5B are an enlarged plan view, a front sectional view, and a front view, respectively, showing a tilt support shaft and a tilt support bearing on the near side, which constitute a part of the off-center amount adjusting means of the first embodiment. 6
FIG. 7 is an exploded perspective view showing, in an enlarged and exploded manner, a tilt support shaft and a tilt support bearing on the rear side which constitute a part of the off-center amount adjusting means which is a main part of the first embodiment.
FIG. 3B is an enlarged plan view and a front sectional view showing a tilt support shaft and a tilt support bearing on the rear side, which constitute a part of the off-center amount adjusting means of the first embodiment.

The above-mentioned off-center amount adjusting means ensures that the trajectory of the spot on the optical disk D irradiated with the laser beam in the radial direction is always on one diameter line passing through the center of the optical disk, as will be described later. The off-center amount is adjusted. The off-center amount adjusting means includes a pair of tilt support shafts 15 and 16 attached to the outside of the side surfaces 6 c and 6 d of the second base 6, and a first base 5 for supporting the pair of tilt support shafts 15 and 16. It comprises a pair of tilt support bearings 20 and 30 attached above, an adjustment screw 39 provided on the tilt support bearing 30 side, and the like.

First, as shown in FIGS. 4 and 5 (a) and 5 (b) in an enlarged manner, the front tilt support shaft 15 and the tilt support bearing which constitute a part of the off-center amount adjusting means of the first embodiment. In the portion 20, a V-shaped groove 15a is formed over the entire circumference at an intermediate portion in the longitudinal direction of the tilt support shaft 15 attached to the outside of the side surface 6c of the second base 6. The shape of the groove formed in the middle portion of the tilt support shaft 15 in the longitudinal direction is not limited to the V-shaped groove 15a, but may be a U-shaped groove or a U-shaped groove. It just needs to fit without sticking.

On the other hand, the tilt support bearing portion 20 mounted on the first base 5 corresponding to the tilt support shaft 15 mounted on the outer side of the side surface 6b of the second base 6 makes the shaft 21 elongated upward. The shaft 2
1, a stepped hole 22a formed on the left end side of the tilt support bearing arm 22 is fitted, an upper portion of the shaft 21 is projected from an upper surface 22b of the tilt support bearing arm 22, and a lower surface of the tilt support bearing arm 22 22
The E-ring 23 is fitted to the shaft 21 in the stepped hole 22a while sliding the c on the first base 5 so as to prevent the tilt support bearing arm 22 from slipping upward.

A shaft 24 is press-fitted into the right end side of the tilt support bearing arm 22 substantially in parallel with the shaft 21 at a predetermined interval, and the shaft 24 is mounted on upper and lower surfaces 22b and 22c of the tilt support bearing arm 22. Projecting upward and downward, respectively. The lower end portion of the shaft 24 press-fitted into the right end side of the tilt support bearing arm 22 is made to pass through the elongated hole 5a formed in the first base 5, and the first base 5 is inserted through the elongated hole 5a.
One end of a tension spring 25 is hooked on the lower end portion of the shaft 24 protruding to the rear surface side of the shaft, and the other end of the tension spring 25 is hooked on the back surface of the first base 5. Accordingly, the tilt support bearing arm 22 is provided with the shaft 24 press-fitted therein and the long hole 5.
While the rotation range is regulated by the arrow a, it is rotatable around the shaft 21 in the directions of arrows C1 and C2, and the tilt support bearing arm 22 is constantly urged in the direction of arrow C1 by the tension spring 25. .

Further, the tilt support shaft 15 attached to the outside of the side surface 6b of the second base 6 enters into a predetermined space between the shaft 21 and the shaft 24 projecting from the upper surface 22b of the tilt support bearing arm 22. I have. At this time, the predetermined interval between the shaft 21 and the shaft 24 is set to a value slightly larger than the diameter of the tilt support shaft 15. The upper surface 22b of the tilt support bearing arm 22 is parallel to the first base 5, and the shaft 21 abuts on the V-shaped groove 15a of the tilt support shaft 15, and the tilt support shaft 15 is connected to the tilt support bearing arm. 22 upper surface 22b
The shaft 24 is also in contact with the shaft 24 at three points.

Thereafter, the shafts 21 and 24 are passed through the two holes 26a and 26b of the disengagement prevention member 26 so that the tilt support shaft 15 does not come out of the predetermined space upward, and the E-rings 27 and 27 are further provided. Is fitted to prevent the tilt support shaft 15 from coming off.

Therefore, the shaft 24 is always pressed against the tilt support shaft 15 by the urging force of the tension spring 25. In particular, even if the tilt support shaft 15 moves by a very small amount, the shaft 24 always keeps in a state of following and contacting the tilt support shaft 15 due to the urging force of the tension spring 25. When the tilt support shaft 15 moves by a very small amount, the shaft 24 and the tilt support shaft 15 slide by a very small amount. Also, in the V-shaped groove 15a of the tilt support shaft 15,
Since the shaft 21 is fitted, the tilt support shaft 1
5 is positioned by the shaft 21 in the axial direction, so that the tilt support shaft 15 has a degree of freedom only in the direction of rotation and rotation about the shaft 21 fitted in the V-shaped groove 15a. .

Next, as shown in FIG. 6 and FIGS. 7A and 7B in an enlarged manner, the tilt support shaft 16 on the back side and the tilt which constitute a part of the off-center amount adjusting means of the first embodiment. In the support bearing portion 30, the tilt support shaft 16 attached to the outside of the side surface 6c of the second base 6 is formed as a round bar.

On the other hand, the tilt support bearing portion 30 mounted on the first base 5 corresponding to the tilt support shaft 16 mounted on the outer side of the side surface 6c of the second base 6, makes the shaft 31 elongate upward. The shaft 3
1 is fitted with a stepped hole 32b formed in a protruding portion 32a formed by projecting the left end side of the tilt support bearing arm 32 upward, and the upper surface 32c is provided on the right side of the protruding portion 32a with the protruding portion 3
It is formed flat one step below 2a. And
An E-ring 33 is fitted to the shaft 31 in the stepped hole 32b while the lower surface 32d of the tilt support bearing arm 32 is in sliding contact with the first base 5 so as to prevent the tilt support bearing arm 32 from slipping upward. On the right side of the protrusion 32a formed on the left end side of the tilt support bearing arm 32, a guide groove 32e for fitting the leaf spring 34 is formed at a depth from above the protrusion 32a to the upper surface 32c. When the leaf spring 34 is fitted into the guide groove 32e, the V-shaped pressing piece 34a of the leaf spring 34 projects toward the upper surface 32c.

A shaft 35 is press-fitted substantially in the center of the tilt support bearing arm 32 substantially in parallel with the shaft 31 at a predetermined interval, and the shaft 35 is attached to the upper and lower surfaces 32c, 32d of the tilt support bearing arm 32. Projecting upward and downward, respectively. The lower end portion of the shaft 35 press-fitted substantially at the center of the tilt support bearing arm 32 is made to pass through the round hole 5b formed in the first base 5, and the first base 5 is made to pass through the round hole 5b.
One end of a tension spring 36 is hooked on the lower end portion of the shaft 35 protruding to the back surface side of the shaft, and the other end of the tension spring 36 is hooked on the back surface of the first base 5. Therefore, the tilt support bearing arm 32 is provided with the shaft 35 press-fitted therein and the round hole 5.
While the rotation range is regulated by b, it is rotatable around the shaft 31 in the directions of arrows D1 and D2, and the tilt support bearing arm 32 is constantly urged in the direction of arrow D1 by the tension spring. .

The second base 6 is mounted on the outside of the side surface 6c of the second base 6 between the leaf spring 34 fitted in the guide groove 32e of the tilt support bearing arm 32 and the shaft 35 projecting substantially in the center of the upper surface 32c. The tilt support shaft 16 is inserted. At this time, the V-shaped pressing piece 34a of the leaf spring 34 is always in contact with the shaft 35 so as to hold the tilt support shaft 16, and generates an urging force to eliminate the gap.
The upper surface 32c of the tilt support bearing arm 32 is the first
The tilt support shaft 16 is parallel to the base 5 and the leaf spring 3
4, the upper surface 32c, and the shaft 35 at three points.

Thereafter, the shafts 31 and 35 are respectively inserted through the two holes 37a and 37b of the disengagement prevention member 37 so that the tilt support shaft 16 does not come off from within the predetermined interval, and the E-rings 38 and 38 are attached. The fitting prevents the tilt support shaft 16 from slipping upward.

Further, on the first base 5, an adjusting screw 39 for pressing the right end side of the tilt supporting bearing arm 32 and the adjusting screw 39 are screwed behind the tilt supporting bearing portion 30. Screw support block 4
0 is attached. At this time, screw support block 4
A screw support block 40 is attached so that when the adjustment screw 39 screwed to 0 is rotated, the adjustment can be made outside the diameter of the optical disc D so that the optical disc D does not interfere.

Accordingly, the tilt support bearing arm 32 is finely adjusted by the adjusting screw 39 so as to rotate around the shaft 31. When the adjusting screw 39 advances and pushes the tilt support bearing arm 32, it rotates in the direction D <b> 2 against the urging force of the tension spring 36. At this time, the shaft 35 and the tilt support shaft 16 are separated from each other, but the biasing force of the leaf spring 34 presses the tilt support shaft 16, and eventually, the shaft 35 and the tilt support shaft 1 are moved.
No. 6 keeps in contact with each other while sliding in very small amounts. The tilt support bearing arm 32 is still in close contact with the adjusting screw 39 due to the urging force of the tension spring 36.

Next, the operation of the off-center amount adjusting means of the first embodiment having the above configuration will be described with reference to FIGS.

FIG. 8 is a plan view showing a state in which an off-center is generated in a radial movement locus of a spot on an optical disk irradiated with a laser beam from an optical pickup in the disk drive device according to the present invention, and FIG. FIG. 6 is a plan view showing a state after adjusting an off-center amount generated in a radial movement locus of a spot on an optical disk irradiated with a laser beam from an optical pickup in the disk drive device according to the present invention.

As shown in FIG. 8, after assembling the disk drive 1A according to the present invention, the radial movement locus of the spot on the optical disk D irradiated with the laser beam from the optical pickup 10 is represented by the optical disk D or the turntable. The center is shifted from the one diameter line indicated by a solid line passing through the center by an off-center amount △ d as indicated by a dashed line, and an off-center is generated. The off-center amount Δd of the distance between the dashed line 32 and one diameter line passing through the center of the optical disk D or the turntable 2 is at most several hundred microns.

As described above, in the disk drive 1A of the first embodiment, the turntable 2 for mounting the optical disk D on the first base 5 is rotatably provided.
The optical pickup 10 is provided on the second base 6 so as to be movable in the radial direction of the optical disc D (the direction of arrow K). Further, the right end of the first base 5 and the right end of the second base 6 are further provided. Is provided with a radial tilt correction means 50 for swinging the entire second base 6 in the height direction with respect to the first base 5.

Further, a pair of tilt support shafts 15 and 16 protruding outside both side surfaces 6b and 6c of the second base 6,
A pair of tilt support bearings 20 and 3 provided on the base 5
0. Parts such as the second base 6 and the optical pickup 10 attached to the second base 6 are pivotally connected to a shaft 21 for supporting a tilt support bearing arm 22 constituting the tilt support bearing section 20 on the near side. The optical disk D can be formed in a plane substantially parallel to the signal surface of the optical disk D.

Here, in order to rotate the second base 6 and components such as the optical pickup 10 attached to the second base 6, the second base 6 is screwed into a screw support block 40 constituting the tilt support bearing 30 on the rear side. The adjusted adjusting screw 39 is used. When the adjusting screw 39 is rotated so as to move forward or backward and the adjusting screw 39 presses the tilt support bearing arm 32 on the back side by the urging force of the tension spring 36, the tilt supporting shaft 16 is integrally tilt-supported. Since the bearing arm 32 rotates about the shaft 31 in the direction of arrow D1 (or the direction of arrow D2), the tilt support shaft 16 supported on the tilt support bearing arm 32 moves in the radial direction of the optical disc D. (In the direction of arrow K), the tilt support shaft 16 supported on the tilt support bearing arm 32 is displaced.
The second base 6 as a whole is rotated in a plane substantially parallel to the first base 5 and in a plane substantially parallel to the optical disc D with the shaft 21 on the near side as a rotation fulcrum. In this case, when the adjusting screw 39 is slightly rotated in the direction of retracting in the direction of arrow E, the entire second base 6 is rotated in the direction of arrow F. At this time, since the position where the adjusting screw 39 can be turned is outside the diameter of the optical disc D as described above, the output signal from the optical pickup 10 when the optical disc D is rotated is observed while observing the output signal. The entire second base 6 is rotated so as to reduce the off-center amount Δd.

Further, the V-shaped groove 15a of the tilt support shaft 15
The shaft 21 is fitted in the second base 6
Has little degree of freedom in the axial direction of the tilt support shaft 15 and the tilt support shaft 16, and is maintained in a state without rattling.

The tilt support bearing arm 2 on the front side
Shafts 21 and 24 protruding from the upper surface 22b of the shaft 2
Is a value slightly larger than the diameter of the tilt support shaft 15, but the gap is eliminated by the action of the tension spring 25. Therefore, the tilt support shaft 15 is always
1. Rotating while contacting the three points of the upper surface 22 of the tilt support bearing arm 22 and the shaft 24.

On the other hand, the tilt support bearing arm 32 on the back side
Spring 34 and upper surface 32c fitted in the guide groove 32e of FIG.
A gap with respect to the tilt support shaft 16 that has entered between the shaft 35 protruding substantially in the center thereof is not always generated because it is absorbed by the leaf spring 34 and the shaft 35. Also, even if this gap is eliminated and the frictional resistance increases, the frictional resistance is very close to the rotation center of the radial tilt, and the resistance torque due to this frictional resistance is very small. Not big enough.

Next, FIG. 9 shows a state after the off-center amount Δd is adjusted, and the off-center amount Δd shown in FIG.
The dashed-dotted line deviated only by this is corrected to pass through the center of the optical disk D or the turntable 2. In this off-center amount adjusting means, the optical pickup 10 is located at a substantially intermediate position between the adjusting screw 39 and the rotation center (shaft 21) of the second base 6, and the optical disk of the tilt support shaft 16 is adjusted by the adjusting screw 39. The moving amount of the optical pickup 10 in the direction orthogonal to the radial direction of the optical disc D is close to half of the moving amount in the radial direction of D. For this reason, even if the adjusting screw 39 is turned greatly, the adjustment sensitivity of the optical pickup 10 can be reduced, and fine adjustment can be performed.

In the off-center amount adjusting means described so far, there is a possibility that the radial position at which the optical pickup 10 reaches the innermost circumference of the optical disk D fluctuates. However, the second base 6 rotates about the shaft 21 as a rotation center, with a contact point between the adjustment screw 39 and the tilt support bearing arm 32 as an action point. The optical pickup 10 in question is located substantially in the middle of the shaft 21 which is the center of rotation, the adjusting screw 39 which is the point of action, and the contact point of the tilt support bearing arm 32. For this reason, the fluctuation amount of the optical pickup 10 is smaller than the fluctuation amount at the action point, and the fluctuation amount is considerably small, so that there is no problem.

Usually, a detection switch 61 is mounted on the first base 5 to detect that the optical pickup 10 has reached the innermost position. When the optical pickup 10 reaches the innermost position, the optical pickup 1
0 itself is to detect the arrival by pressing the detection switch 61. However, if the contact point between the detection switch 41 and the optical pickup 10 is set at a position closer to the shaft 21 which is the center of rotation, the fluctuation ΔL of the detection position can be further reduced.

After the off-center amount is adjusted, the radial movement locus of the spot on the optical disk D irradiated with the laser beam is always on one diameter line passing through the center of the optical disk D. Recording and reproduction can be performed well.

After the adjustment is completed, it is preferable that the first base 5, the tilt support bearing portion 20, and the tilt support bearing portion 30 be fixed with an ultraviolet curing adhesive.

<Second Embodiment> FIG. 10 shows a second embodiment according to the present invention.
FIG. 11 is a plan view of the optical disk drive of the embodiment, and FIG. 11 is an enlarged and disassembled view of a tilt support shaft and a tilt support bearing on the front side which constitute a part of an off-center amount adjusting means which is a main part of the second embodiment. FIG. 12 is an exploded perspective view, FIG. 12 is an enlarged plan view showing a tilt support shaft and a tilt support bearing on the near side which constitute a part of the off-center amount adjusting means of the second embodiment, and FIG. FIG. 14 is an exploded perspective view showing, in an enlarged and exploded manner, a tilt support shaft and a tilt support bearing portion on the rear side, which constitute a part of the off-center amount adjusting means which is a main part. FIG. 14 shows one example of the off-center amount adjusting means of the second embodiment. It is the top view which expanded and showed the tilt support shaft of the back side which comprises a part, and the tilt support bearing part.

The optical disk drive 1B according to the second embodiment of the present invention shown in FIG. 10 has the same configuration as that of the optical disk drive 1A according to the first embodiment except for a part. Here, for convenience of explanation, the same reference numerals are given to the constituent members shown above, and the constituent members shown above are appropriately described as necessary, and new reference numerals are given to constituent members different from the conventional ones. A description is given below.

As shown in FIG. 10, in the optical disk drive 1B according to the second embodiment of the present invention, the turntable 2 for mounting the optical disk D on the first base 5 is rotatably provided. 2 Optical pickup 10 on base 6
Is provided so as to be movable in the radial direction of the optical disc D (the direction of arrow K).
As in the first embodiment, a radial tilt correcting means 50 for swinging the entire second base 6 in the height direction with respect to the first base 5 is provided on the right end side of the base 6.

Here, in the second embodiment, the off-center amount adjusting means is different from that of the first embodiment, and the off-center amount adjusting means is a main part of the second embodiment.

That is, a pair of tilt support shafts 71 and 72 are provided on the front side surface 6b of the second base 6 and the rear side surface 6c opposed to the side surface 6b with the optical pickup 10 interposed therebetween. The tilt support shafts 7 are attached along a straight line substantially orthogonal to the pair.
1, 72 project outside each side 6b, 6c. At this time, the straight line on which the pair of tilt support shafts 71 and 72 is attached is set at a position where the signal surface on the inner peripheral side of the optical disk D intersects with the diameter near the lead-in.

On the other hand, on the first base 5, a pair of tilt support bearings 80, 90 are provided on the side surfaces 6b, 6c of the second base 6.
Are mounted corresponding to the pair of tilt support shafts 71 and 72 mounted on the pair, and the pair of tilt support shafts 71 and 72 are supported by the pair of tilt support bearing portions 80 and 90.

First, as shown in an enlarged manner in FIGS. 11 and 12, the front tilt support shaft 71 and the tilt support bearing portion 8 constituting a part of the off-center amount adjusting means of the second embodiment.
At 0, a pivot 71a is formed as a convex conical surface at the longitudinal end of the tilt support shaft 71 attached to the outside of the side surface 6c of the second base 6.

On the other hand, the tilt support bearing portion 80 mounted on the first base 5 corresponding to the tilt support shaft 71 mounted on the outer side of the side surface 6b of the second base 6 has a bearing block 81 whose first base is screwed by a screw 82. 5 fixed. In the bearing block 81, a pivot bearing 81b is formed as a concave conical surface on a surface 81a of the tilt support shaft 71 which faces the pivot 71a. Here, the pivot bearing 81b of the bearing block 81 is formed such that the bottom surface of the conical surface is wider than the pivot 71a of the tilt support shaft 71.

The pivot 71 of the tilt support shaft 71
By fitting a into the pivot bearing 81b of the bearing block 81, the apex of the pivot 71a and the apex of the pivot bearing 81b serve as fulcrums for rotating the entire second base 6 as described later.

Next, as shown in FIGS. 13 and 14 in an enlarged manner, the tilt support shaft 72 and the tilt support bearing 9 on the rear side which constitute a part of the off-center amount adjusting means of the second embodiment.
At 0, a pivot 72a is formed as a convex conical surface at the longitudinal end of the tilt support shaft 72 attached to the outside of the side surface 6c of the second base 6.

On the other hand, the tilt support bearing portion 90 mounted on the first base 5 corresponding to the tilt support shaft 72 mounted on the outer side of the side surface 6c of the second base 6 has a shaft 91 vertically suspended. A long hole 92a formed in the bearing block 92 is rotatably fitted to the shaft 91 so that the E-ring 93 prevents upward removal.

The bearing block 92 has a surface 92 b at a position facing the pivot 72 a of the tilt support shaft 72.
The pivot bearing 92c is formed as a concave conical surface, and the pivot 72a of the tilt support shaft 72 is fitted into the pivot bearing 92c. Also in this case, the pivot bearing 92c of the bearing block 92 has the tilt support shaft 7
The bottom surface of the conical surface is formed to be wider than the second pivot 72a.

Further, one end of the tension spring 94 is hooked on a projection 92e which projects the surface 92b of the bearing block 92 from the side surface 92d, and the other end of the tension spring 94 is hooked on the back surface of the first base 5. I have.

An adjusting screw 95 for pressing the side surface 92d and a screw support block 96 for screwing and supporting the adjusting screw 95 are mounted near the side surface 92d of the bearing block 92. At this time, the tilt support shaft 72 fitted to the pivot bearing 92c of the bearing block 92 and the adjusting screw 95 have a substantially right-angled relationship with each other,
The biasing force of the tension spring 94 acts in a direction substantially at the intermediate position between the tilt support shaft 72 and the adjusting screw 95.

Next, the operation of the off-center amount adjusting means of the second embodiment having the above configuration will be described.

Here, in order to rotate the second base 6 and components such as the optical pickup 10 attached to the second base 6, the second base 6 is screwed into a screw support block 96 constituting the tilt support bearing section 90 on the rear side. The adjusted screw 95 is used. When the adjusting screw 95 is rotated so as to move forward or backward, and the adjusting screw 95 presses the rear bearing block 92 via the urging force of the tension spring 94, the bearing block 92 is rotated about the shaft 91 by the optical disc D. Accordingly, the tilt support shaft 72 supported on the bearing block 92 is integrally displaced in the radial direction of the optical disc D (the direction of the arrow K). Therefore, the pivot bearing 92c of the bearing block 92
The pivot 71 of the tilt support shaft 71 in which the entire second base 6 is attached to the front side integrally with the tilt support shaft 72 fitted to
The vertex of a and the pivot bearing 81b of the bearing block 81
Of the first base 5 in a plane substantially parallel to the first base 5 and a plane substantially parallel to the optical disk D.

At this time, the position where the adjusting screw 95 can be turned is located outside the diameter of the optical disk D as in the first embodiment, so that the optical pickup 10 when the optical disk D is rotated is rotated. The second base 6 is rotated as a whole while observing the output signal from the controller to adjust so that the off-center amount decreases.

After the off-center amount has been adjusted, the radial movement locus of the spot on the optical disk D irradiated with the laser beam is always on one diameter line passing through the center of the optical disk D. Recording and reproduction can be performed well.

After the adjustment is completed, it is preferable that the first base 5, the tilt support bearing portion 80, and the tilt support bearing portion 90 are fixed with an ultraviolet curing adhesive.

[0088]

According to the optical disk drive apparatus of the present invention described in detail above, the first base on which the turntable for rotating the optical disk is mounted, the optical pickup is movably mounted in the radial direction of the optical disk, and the optical disk is mounted. A second base on which a pair of tilt support shafts is mounted on a straight line substantially perpendicular to the moving direction of the optical disk on the inner peripheral side of the optical pickup, and a laser beam emitted from the optical pickup is constantly transmitted to the optical disk as a signal. A radial tilt correcting means for swinging the entire second base relative to the first base in a height direction about a pair of tilt support shafts so as to make the light incident substantially perpendicular to the radial direction of the surface; In particular, when one of the pair of tilt support shafts is used as a fulcrum, By displacing the other tilt support shaft in the radial direction of the optical disk so as to rotate in a plane substantially parallel to the optical disk, the radial movement locus of the spot on the optical disk irradiated with the laser beam always passes through the center of the optical disk. The provision of the off-center amount adjusting means for adjusting the off-center amount so as to be on one diameter line enables the optical disc to be favorably recorded and reproduced by the optical pickup. Further, when the off-center amount is adjusted by the off-center amount adjusting means, the off-center amount is adjusted outside the diameter of the optical disk, so that the off-center amount is observed while the output signal from the optical pickup is observed while the optical disk is rotated. Adjustment is possible, and the adjustment is easy but highly accurate.

[Brief description of the drawings]

FIG. 1 is a perspective view of an optical disk drive according to a first embodiment of the present invention.

FIG. 2 is a plan view of the optical disk drive of the first embodiment according to the present invention.

FIG. 3 is an exploded perspective view showing the optical disk drive of the first embodiment according to the present invention in an exploded manner.

FIG. 4 is an exploded perspective view showing, in an enlarged manner, a tilt support shaft and a tilt support bearing on the front side, which constitute a part of an off-center amount adjusting unit which is a main part of the first embodiment.

FIGS. 5A and 5B are a plan view and a front sectional view showing, on an enlarged scale, a front tilt support shaft and a tilt support bearing which constitute a part of the off-center amount adjusting means of the first embodiment; It is.

FIG. 6 is an exploded perspective view showing, in an enlarged manner, a tilt support shaft and a tilt support bearing on the rear side, which constitute a part of an off-center amount adjusting means which is a main part of the first embodiment.

FIGS. 7 (a) and 7 (b) are enlarged plan and front sectional views showing a tilt support shaft and a tilt support bearing on the rear side which constitute a part of the off-center amount adjusting means of the first embodiment; It is.

FIG. 8 is a plan view showing a state in which a radial movement locus of a spot on an optical disk irradiated with a laser beam from an optical pickup is off-center in the disk drive device according to the present invention.

FIG. 9 is a plan view showing a state after adjusting an off-center amount generated in a radial movement locus of a spot on an optical disk irradiated with a laser beam from an optical pickup in the disk drive device according to the present invention. .

FIG. 10 is a plan view of an optical disk drive according to a second embodiment of the present invention.

FIG. 11 is an exploded perspective view showing, on an enlarged scale, a tilt support shaft and a tilt support bearing on the front side, which constitute a part of an off-center amount adjusting means which is a main part of the second embodiment.

FIG. 12 is an enlarged plan view showing a tilt support shaft and a tilt support bearing on the front side, which constitute a part of an off-center amount adjusting means of the second embodiment.

FIG. 13 is an exploded perspective view showing, on an enlarged scale, a rear tilt support shaft and a tilt support bearing that constitute a part of an off-center amount adjusting unit that is a main part of the second embodiment.

FIG. 14 is an enlarged plan view showing a tilt support shaft and a tilt support bearing on the rear side which constitute a part of the off-center amount adjusting means of the second embodiment.

15A and 15B are a perspective view and a plan view for explaining a guide device of a conventional optical pickup device.

[Explanation of symbols]

1A: Optical disk drive of the first embodiment, 1B: Optical disk drive of the second embodiment, 2 ... turntable, 4 ...
Spindle motor, 5: first base, 6: second base,
7 ... Long guide shaft, 8 ... Long guide rail, 9 ... Optical pickup support base, 10 ... Optical pickup, 15,1
6 ... a pair of tilt support shafts, 15a ... V-shaped groove, 20,3
0 ... a pair of tilt support bearings, 21 ... shaft, 22
... Tilt support bearing arm, 24 ... Shaft, 25 ... Tension spring, 31 ... Shaft, 32 ... Tilt support bearing arm, 34 ... Leaf spring, 35 ... Shaft, 36 ... Tension spring,
39: adjusting screw, 40: screw support block, 50: radial tilt correcting means, 71, 72: pair of tilt support shafts, 71a: pivot, 72a: pivot, 80, 90
... a pair of tilt support bearings, 81 ... bearing block,
81b ... Pivot bearing, 91 ... Shaft, 92 ... Bearing block, 92c ... Pivot bearing, 93 ... Tension spring, 95 ... Adjustment screw, 96 ... Screw support block, D ...
optical disk.

Claims (4)

[Claims] A first base on which a turntable for rotating the optical disk is mounted; an optical pickup movably mounted in a radial direction of the optical disk; and an inner peripheral side of the optical disk with respect to a moving direction of the optical disk. A second base on which a pair of tilt support shafts are mounted on a straight line substantially orthogonal to the optical pickup, and a laser beam emitted from the optical pickup is always substantially perpendicular to a radial direction of a signal surface of the optical disc. An optical disc driving device comprising: a radial tilt correcting means for swinging the entire second base relative to the first base in a height direction about the pair of tilt support shafts so as to make the pair of light incident on the pair of tilt support shafts. The entire second base is substantially the same as the optical disk, with one of the tilt support shafts serving as a fulcrum. By displacing the other tilt support shaft in the radial direction of the optical disc so as to rotate in a plane, the radial movement locus of the spot on the optical disc irradiated with the laser beam always moves to the center of the optical disc. An optical disk drive comprising an off-center amount adjusting means for adjusting an off-center amount so as to be on one diameter line passing therethrough. 2. The optical disk drive according to claim 1, wherein said off-center amount adjusting means rotatably mounts a pair of tilt support bearing arms on said first base in correspondence with said pair of tilt support shafts. The pair of tilt support bearing arms are supported on the pair of tilt support bearing arms, and one of the tilt support bearing arms supporting one of the tilt support shafts serves as a pivot point of the second base. An optical disc driving device for pressing the other tilt support bearing arm supporting the other tilt support shaft in a direction in which the off-center amount decreases. 3. The optical disk drive according to claim 1, wherein said off-center amount adjusting means forms a pivot as a convex conical surface at a tip of said pair of tilt support shafts, and further comprises a pair of tilt support shafts. A pivot bearing having a concave conical surface was formed in a pair of bearing blocks for fitting in opposition to the pivot, and one of the pair of bearing blocks was fitted in the tilt support shaft opposed thereto. Fixed on the first base in the state
The other bearing block is rotatably mounted on the first base in a state where the other bearing block is fitted to the tilt support shaft facing the other bearing block. An optical disk drive device for pressing in a direction in which the off-center amount decreases. 4. The optical disk drive according to claim 2, wherein the adjustment of the off-center amount by the off-center amount adjusting means is performed outside a diameter of the optical disk. Optical disk drive.