JP3428832B2 - Adjustment device in disk device - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a CD and a CD-RO.
The present invention relates to a disk device such as an M or a DVD, and more particularly to an adjusting device in a disk device capable of vertically setting an optical axis of a head and a recording surface of a disk with high accuracy.

[0002]

2. Description of the Related Art FIG. 5 is a partial side view showing a disk supporting portion of a conventional CD player, and FIG. 6 is a partial side view showing a state in which a rotation shaft of a motor is inclined with respect to a mounting surface of the motor. FIG. 7 is a side view showing a conventional motor shaft adjusting device. In FIG. 5, a spindle motor 1 for rotating a disk D has a pedestal 2 interposed between it and a mechanism chassis 6 and is fixed by screws 7, 7. Turntable 3
Are rotatably supported by the rotary shaft 1a of the spindle motor 1. The disk D is installed on the turntable 3 and is rotationally driven by the motor 1.

An optical head 8 for reading information recorded on the disk D is provided along the guide member 5 so as to be slidable in the X-axis direction in the figure. The optical head 8 condenses laser light from a light source (not shown) with the objective lens 9 and irradiates the pit D1 on the surface of the disk D. The intensity of the returned light is modulated by the pit D1, and the light is received by the light receiving element to detect the signal. In the optical head 8, the objective lens 9 is finely moved in the tracking direction to perform tracking servo to follow the track, and the objective lens 9 is finely moved in the optical axis direction to perform focus servo.

In this type of disc player, the objective lens 9 is attached to the recording surface (pit D1 forming surface) of the disc D.
It is preferable that the optical axis O-O of the above is perpendicularly opposed. For that purpose, it is necessary to assemble the rotating shaft 1a of the motor 1 so as to maintain the parallelism with high accuracy with respect to the optical axis OO. For example, as shown in FIG. 6, the rotation axis 1a is the optical axis OO.
If the turntable 3 is not maintained perpendicular to the optical axis O-O when it is tilted with respect to the parallel line O1-O1, the disk D mounted on the turntable 3 is also rotationally driven in the tilted posture. Therefore, the optical axis O-O of the objective lens 9
Will not be illuminated perpendicularly to the recording surface of the disk D, and the spot of the laser beam formed on the recording surface will be distorted and the detection accuracy of the pit D1 will be reduced.
Here, the rotation axis 1a is a parallel line O1-O1 of the optical axis OO.
The cause of tilting relative to is the result of cumulative dimensional tolerances for each part. In order to correct this inclination, as shown in FIG. 7, the rotary shaft 1a is aligned with the parallel line O1-O1, that is, the spacer S is interposed at a predetermined position between the motor 1 and the pedestal 2. Thus, the work of setting the parallelism of the rotary shaft 1a with respect to the optical axis OO is performed.

FIG. 8 is a perspective view showing a conventional support mechanism for a guide member. Guide member 5 shown in FIGS.
Are supported by a supporting mechanism as shown in FIG. That is, the support 6a and the support base 6b are fixedly provided on the mechanism chassis 6. One end surface of the guide member 5 is inserted and retained in a support hole 6a1 formed in the support 6a, and the other end portion of the guide member 5 is supported by a recess 6b1 provided in the support base 6b. Support base 6
In b, the screw 10b is inserted into the mounting hole 10a of the leaf spring 10 bent into a crank shape and screwed into the screw hole 6b2 formed in the support base 6b. The end of the guide member 5 is pressed by the elastic force of the leaf spring 10 and fixed in the recess 6b1 of the support base.

[0006]

However, in the disk device having the above structure, the parallelism between the axis of the rotary shaft 1a that pivotally supports the turntable 3 and the optical axis OO of the objective lens 9 is set with high accuracy. In order to do so, it is necessary to two-dimensionally adjust the rotary shaft 1a in both the radial direction (tilt in the X direction) and the tangential direction (tilt in the Y direction). Further, when the parallelism of the pair of guide members 5 supporting both sides of the optical head 8 is out of alignment, that is, when the pair of guide members 5 are arranged such that their axes are twisted with respect to each other. As the lens moves along the guide member 5, the optical axis OO tilts depending on its position, and it becomes impossible to always maintain the parallel state with the rotating shaft 1a.

When the optical axis 1a is tilted in the tangential direction (Y direction) by the spacer S, the distance between the objective lens 9 of the optical head 8 and the recording surface of the disk D changes, and this distance is extremely large. It may become short. When this distance becomes short, the working distance of the objective lens 9 and the disc D
The difference from the recording surface becomes large and it becomes necessary to perform an unnecessary focus correction operation, which adversely affects the focus servo operation. Further, the weight of the head of the conventional disk device for CD has been relatively light. But DV
For a D (Digital Versatile Disk) or the like, the weight of the head tends to be heavier than that of a CD. Therefore, the conventional support structure shown in FIG. 8 cannot withstand an accident such as dropping during transportation, and the momentary impact force becomes larger than that of the conventional one because the weight of the head becomes heavier. 5 is disengaged from the recess 6b1 or the leaf spring 1
0 may be deformed.

The present invention is to solve the above-mentioned conventional problems, and the perpendicularity between the optical axis and the recording surface of the disk can be set with high accuracy and easily, and the height position of the optical head can be set. It is an object of the present invention to provide an adjusting device in a disk device capable of adjusting.

Further, the present invention provides an adjusting device in a disk device in which the holding strength of the guide member is increased so as to prevent the guide member from coming off when an excessive impact is applied. Is intended.

[0010]

SUMMARY OF THE INVENTION An adjusting device of the present invention comprises a pair of guide members provided on a chassis in parallel at a predetermined interval, and both ends of the guide members are supported by the guide members. In a disk device provided with a moving read or write head, both of the holding members that hold both ends of at least one guide member are supported by a support base fixed to the chassis side,
The support base has a cylindrical shape extending in a direction perpendicular to the moving direction of the head, and a screw hole is formed in an end surface of the support base , and the holding member has a guide inserted in an outer peripheral surface of the support base. a hole, and the convex portion is provided to be fitted to the chassis side at a position deviated from the guide hole, the holding member relative to the support base, around the shaft can only slide of the the supporting base in the axial direction Is supported so as not to rotate, the holding member is biased by an elastic member in a direction away from the chassis side, and an adjusting screw that is inserted into the holding member and screwed into the screw hole is provided. The position of the holding member is set by adjusting the tightening amount of the adjusting screw.

In the above, the elastic member is a chassis
Is a leaf spring fixed to the side, and the tip of the leaf spring is
It may be elastically pressed to the lower end of the holding member.

Further, in the present invention, in addition to the above configuration, the rotary shaft of the turntable on which the disk is installed is adjustable so as to tilt only in the moving direction of the head, that is, the rotary shaft is set in the moving direction of the head ( It is preferable to provide an adjusting device capable of adjusting the tilt only in the radial direction).

The pair of guide members in the present invention are, as shown in FIG. 1, each a guide shaft or a guide rail for guiding the optical head. Alternatively, one guide member (main-side guide member) may be, for example, a screw shaft that also serves as a feed mechanism that moves the optical head.

The adjusting device of the present invention is capable of adjusting the height positions of both ends of at least one guide member from the chassis. That is, the heights of both guide shafts from the chassis side can be individually adjusted. Alternatively, both ends of both of the pair of guide members may be attached so that the height position from the chassis side can be adjusted.

As the adjustment work, the height positions of both end portions of the other guide member are adjusted with reference to the main guide member. This operation is performed by adjusting the tightening amount of the screw that holds the holding member to the support base.
With this operation, one guide member can be set to be parallel to the main guide member. Furthermore, adjust the height position of the entire guide member to the chassis,
It is also possible to adjust the tilt between both guide members in the Y direction so that there is no tilt in the tangential direction between the rotation axis and the optical axis of the turntable.

Further, since the height position of the optical head with respect to the chassis can be adjusted, the distance between the disk installed on the turntable and the objective lens of the optical head can be set appropriately.

By the above adjustment, the parallelism of the pair of guide members can be set, and tilting of the rotary shaft and the optical axis of the head in the tangential direction can be eliminated. Also, if necessary,
By adjusting the rotation axis only in the tilt in the radial direction, the parallelism between the rotation axis and the optical axis of the head can be set with high accuracy.

That is, according to the present invention, the parallelism between the rotation axis and the optical axis is ensured only by adjusting both ends of one guide member in the height direction and tilting the rotation axis in the radial direction. Moreover, since the pair of guide members are parallel to each other, the rotation axis and the optical axis can be kept parallel to each other regardless of the position of the head.

Further, in the adjusting mechanism, since both end portions of the guide member are completely held and fixed by the holding members, the guide member does not come off due to external impact. Further, by fitting the holding member and the support base in a concavo-convex manner so that the holding member slides only in the adjustment direction with respect to the support base, the holding member and the support base will not come off due to an external impact, for example, for DVDs and the like Even when a heavy head is used as described above, the strength of the adjusting mechanism can be increased and the durability is excellent.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 shows a disk drive unit of a vehicle-mounted disk device according to the present invention, and is a perspective view showing a mechanism chassis with its back surface facing upward. In the disk drive unit shown in FIG. 1, the mechanical chassis 16
Is made of sheet metal, and a bracket B made of synthetic resin is fixed to the back surface of the mechanism chassis 16. The moving base 18 on which the optical head H is mounted is guided by a pair of guide members (guide shafts) 14 and 15. Both ends of one guide member (main shaft) 14 are fixed to supports B1 and B2 provided on the bracket B. Both ends of the other guide member 15 are held by holding members 21 and 22. The bracket B has a tracking motor 25,
The reduction gear train 26 and the feed screw shaft 27 are supported, and a female screw member 29 supported by the moving base 18 via a leaf spring 28 is screwed onto the feed screw shaft 27. The spindle motor 11 is fixed to the adjustment pedestal 30 at one end in the X-axis direction on which the moving base 18 slides.
The rotating shaft 11a is located on the front side of the mechanism chassis 16 (Z in the figure).
The turntable 13 is fixed to the tip of the rotary shaft 11a so as to project in the axis (-) direction.

For example, a disc D such as a CD, a CD-ROM or a DVD is loaded on the turntable 13, clamped, and rotationally driven by the spindle motor 11. The moving base 18 moves from the inner peripheral side to the outer peripheral side of the disk D by the rotational force of the feed screw shaft 27. Then, from the objective lens L of the optical head H to the disc D
Is irradiated with laser light, and the reflected light is detected by the light receiving element in the optical head H, and the signal is read.

FIG. 2 is a sectional view taken along the line II-II in FIG. 1 showing an example of the configuration of an adjusting device for adjusting the tilt of the motor rotating shaft 11a in the radial direction. A pressing portion 30a is integrally formed on the adjustment pedestal 30 that fixes the spindle motor 11. A coil spring 32 is interposed between the pressing portion 30a and the mechanism chassis 16. Adjustment screw 31
Is inserted into the pressing portion 30a, and the coil spring 3
The inside of 2 is inserted and screwed to the mechanism chassis 16. The coil spring 32 is selected such that its free length is longer than the gap length h between the pressing portion 30a and the mechanism chassis 16, and the pressing portion 30a always applies the urging force from the coil spring 32 in the Z-axis (-) direction in the figure. is recieving. Therefore, when the adjusting screw 31 is tightened to bring the pressing portion 30a closer to the mechanism chassis 16, the rotary shaft 11a of the spindle motor 11 can be tilted in the α1 direction in the figure. Further, when the adjusting screw 31 is rotated in the slack direction from this state, the rotating shaft 11a can be tilted in the α2 direction by the biasing force of the coil spring 32.

That is, by rotating the adjusting screw 31, the tilting direction and the tilting amount of the rotary shaft 11a in the radial direction can be adjusted. In the present invention, the device for adjusting the inclination of the adjustment pedestal 30 that supports the spindle motor 11 is provided at only one location, and the adjustment member is only the adjustment screw 31. Therefore, the rotary shaft 11a can only adjust the tilt in the radial direction, and does not adjust the tilt in the other directions.

FIG. 3 is an enlarged perspective view showing one structural example of an adjusting device for adjusting the tilt of the rotation axis and the optical axis of the disk device in the tangential direction according to the present invention, and FIG.
It is sectional drawing seen from the V direction. As shown in FIGS.
In this guide member adjusting device, both ends of one guide member 15 are securely held and fixed by the holding members 21 and 22. Holding holes 21a and 22a are formed in the surfaces of the holding members 21 and 22 facing each other, and the end faces of the guide members are fitted and fixed in the holding holes 21a and 22a without rattling. Holding members 21,2
Inside 2 is a small hole 2 for inserting a screw that extends in the Z direction in the figure.
1b, 22b and large holes 21c, 22c serving as guide holes
Are formed. The small holes 21b and 22b are the holding members 2
1, 22 are opened at the upper ends, and the large holes 21c, 22c are opened at the lower ends.

The mechanism chassis 16 has a pair of support bases 34,
34 is fixed. Caulking portions 34b and 34b are integrally formed at the lower ends of the support bases 34 and 34 so as to project integrally.
It is crimped and fixed on the back side of. Holding member 21,
The large holes 21c and 22c serving as guide holes of 22 are fitted into the cylindrical support bases 34 and 34 in a recessed and slidable manner without a gap, and the holding members 21 and 22 are attached to the support bases 34 and 34 in a Z direction. It is slidably guided in the direction.

In the vicinity of the support base 34 on the mechanism chassis 16, a leaf spring 23 as an urging member is attached by a fixing means such as caulking. The leaf spring 23 is formed by pressing a thin metal leaf spring material,
Arm part 23 bent upward (Z-axis (+) direction)
It has a, and its tip is a support portion 23b. The support portion 23b is formed in an arc shape and has a radius of curvature larger than the outer diameter of the support base 34.
The underside of the is being oppressed. Therefore, the leaf spring 23 is
The arm portion 23a exerts an elastic force in the Z (+) direction in the drawing around the bent root portion, and the holding members 21 and 22 externally inserted on the support base 34 are biased in the Z (+) direction. .

From above the holding members 21 and 22,
The adjusting screw 24 is inserted into the small holes 21b and 22b, and is screwed into the screw holes 34a formed in the support bases 34 and 34. By tightening the adjusting screw 24, the holding members 21 and 22 can be adjusted toward the mechanism chassis 16 (Z-axis (-)) direction. On the contrary, when the adjusting screw 24 is loosened, the holding member is urged by the leaf spring 23. The parts 21 and 22 are lifted up and their positions can be adjusted in the Z-axis (+) direction shown.
Therefore, the rotation of the adjusting screw 24 causes the holding members 21, 2 to rotate.
2 can be moved up and down in the Z-axis direction, and the guide member 15
It is possible to adjust the height of. Further, the relative twist between the guide member 14 (main shaft) and the guide member 15 can be adjusted so that the guide members 14 and 15 face each other in parallel, and the parallelism between the guide members 14 and 15 is maintained. In this state, it is possible to change only the height of the guide member 15 side. By adjusting the height of the guide member 15, the head moving surface including the guide member 15 can be rotated in the tangential direction with the guide member 14 (main shaft) as a reference (center).

It should be noted that laterally projecting portions 21d and 22d are integrally provided at the lower portions of the holding members 21 and 22, and a cylindrical small convex portion 21 extending in the Z-axis (-) direction in the figure is provided on the bottom surface thereof.
e and 22e are integrally formed. Mechanism chassis 16
The small hole 16 into which the small convex portions 21e and 22e can be inserted
b, 16b are formed. When the height of the holding members 21 and 22 with respect to the chassis 16 is adjusted, the small convex portion 21
e and 22e are located in the small holes 16b, 16b, and move up and down,
The rotation of the holding members 21, 22 about the hole 16a is prevented, and the holding holes 21a, 22a can be maintained in a state of facing each other. Therefore, the guide member 15 can be kept parallel to the X-axis direction with high accuracy, and the inclination in the XY plane can be prevented from occurring.

As shown in FIG. 3, irregularities having a constant pitch are formed in the circumferential direction on the outer peripheral surface of the screw head of the adjusting screw 24 used in this guide member adjusting device. Further, steps 21f and 22f are formed on the heads of the holding members 21 and 22 through which the adjusting screws 24 are inserted. An uneven surface facing the unevenness of the adjusting screw 24 is formed on the inner surfaces of the steps 21f and 22f. However, the convex portion on the adjusting screw 24 side and the convex portion on the steps 21f and 22f side are not in contact with each other, and a gap 21g is formed between both convex portions (see FIG. 3). Therefore, after the height positions of the holding members 21 and 22 are set, the adjusting screw 24 can be reliably fixed to the holding members 21 and 22 by injecting the adhesive into the gap 21g. Adjusting screws 24, 2
It is possible to prevent the occurrence of slack in item 4.

Next, a method of adjusting the disk device will be described. In the illustrated example, the main guide member 14 of the pair of guide members is fixed, so that only the guide member 15 side is adjusted with reference to the guide member 14. However, the same adjusting device as shown in FIG. 3 may be provided at both ends of the main guide member 14 to adjust the relative posture of the guide member 15 with respect to the mechanism chassis 16. In the embodiment shown in FIG. 1 and subsequent figures, the guide member 15
The relative position of the guide member 15 with respect to the guide member 14 is adjusted by rotating the adjusting screws 24, 24 of the adjusting device provided at both ends of the guide member 14, respectively. That is, by rotating the adjusting screws 24 and 24 individually, the inclination angle of the guide member 15 in the XZ plane and the height position adjustment in the Z direction are performed.

By adjusting the inclination angle of the guide member 15 in the XZ plane, the guide member 15 and the guide member 1 can be adjusted.
4 is set parallel to each other, and in the state where this parallel is maintained, the entire guide member 15 is moved up and down in the Z direction to adjust the height with respect to the mechanism chassis 16, so that both central axes of the guide members 14 and 15 are adjusted. It is possible to perform tilt adjustment in the tangential direction (Y direction) of the included plane (moving surface of the optical head H). By this adjustment, relative tilting of the optical axis of the objective lens L of the optical head H, which is moved by the parallel guide members 14 and 15, and the rotation axis 11a in the tangential direction can be eliminated. Further, the adjusting screw 31 in the adjusting device shown in FIG. 2 is rotated to adjust the tilt of the rotary shaft 11a of the spindle motor 11 with respect to the radial direction (X direction), and the tilt between the rotary shaft 11a and the optical axis of the objective lens L is adjusted. The relative tilt in the radial direction is adjusted.

As described above, by adjusting the adjusting screws 24, 24 provided at both ends of the guide member 15 and the adjusting screw 31 shown in FIG. The rotation axis 11a and the optical axis of the optical head H can be set parallel to the tilts in both the radial direction and the tangential direction. Also, the guide members 14 and 15
Since the movable base 18 and the optical head H move to any position along the guide members 14 and 15, the rotary shaft 11a and the optical axis tilt relative to each other in the writing direction. In this case, the optical axis of the optical head H can be always applied perpendicularly to the disc D, and highly accurate reproducing operation or recording operation can be performed.

Both ends of the guide member 15 are inserted into the holding holes 21a and 22a of the holding members 21 and 22 to be completely held, and the holding members are elastically supported by the leaf springs 23. Holding member 2
1 and 22 are adjusting directions (Z direction) with respect to the support bases 34 and 34.
The guide member 15 is supported so that it can slide only and does not move relatively in the other directions, so that even when a strong external impact is applied, both ends of the guide member 15 do not come off. In the above, the support bases 34, 3
Although the leaf springs 23, 23 are used to bias the member 4 in the direction away from the mechanism chassis 16, a coil spring may be used instead of the leaf spring.

[0034]

According to the present invention described in detail above, the parallelism of the pair of guide members for guiding the head can be adjusted with high accuracy, and the height position of the head with respect to the chassis can be adjusted. Furthermore, if the tilting of the rotary shaft in the radial direction can be adjusted, the rotary shaft and the optical axis can be kept parallel to both the radial direction and the tangential direction by providing a minimum number of adjustment points. It can be adjusted to.

Furthermore, since both ends of the guide member can be held securely, the guide member is resistant to external impact.

[Brief description of drawings]

FIG. 1 is a perspective view showing an in-vehicle disk drive unit of the present invention with its back surface facing upward;

FIG. 2 is a sectional view taken along the line II-II in FIG. 1, showing an example of the configuration of an adjusting device that adjusts the radial tilt of the rotary shaft.

FIG. 3 is an enlarged perspective view showing a configuration example of an adjusting device provided at both ends of a guide member,

4 is a cross-sectional view seen from the IV direction in FIG. 3,

FIG. 5 is a partial side view showing a disc support portion of a conventional CD player,

FIG. 6 is a partial side view showing a state where the rotary shaft is tilted,

FIG. 7 is a side view showing a conventional adjusting device for adjusting the inclination of a rotary shaft;

FIG. 8 is a perspective view showing a conventional guide member support mechanism;

[Explanation of symbols]

11 Spindle motor 13 turntable 14, 15 Guide member 16 mechanical chassis 21,22 holding member 21a, 22a holding holes 23 leaf spring 24 Adjustment screw 30 Adjustment base 31 Adjustment screw 32 coil spring 34 Support

Claims (3)

(57) [Claims] 1. A pair of guide members provided in parallel on a chassis at predetermined intervals, and a read or write head having both ends supported by the guide members and movable along the guide members. In the disk device, at least one of the holding members for holding both ends of the guide member is supported by a supporting base fixed to the chassis side, and the supporting base is perpendicular to the moving direction of the head. In a cylindrical shape extending in any direction, a screw hole is formed in the end surface thereof, and the holding member has a guide hole inserted into the outer peripheral surface of the support base and a chassis hole at a position deviated from the guide hole on the chassis side. The holding member is supported by the support base so as to be slidable only in the axial direction of the support base so as not to rotate around the shaft. The holding member is biased by the elastic member in a direction away from the chassis side, and an adjusting screw that is inserted into the holding member and screwed into the screw hole is provided, and by adjusting the tightening amount of the adjusting screw, An adjusting device in a disk device, wherein a position of the holding member is set. 2. The adjusting device for a disk device according to claim 1, wherein the elastic member is a leaf spring fixed to the chassis side, and a tip portion of the leaf spring is elastically pressed against a lower end of the holding member. 3. The adjusting device in the disk device according to claim 1, wherein the rotary shaft of the turntable on which the disk is installed is adjustable so as to tilt only in the moving direction of the head.