JP2008052852A - Optical disk device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical disk device where tolerance is set easily when designing by minimizing the irregularity of a pitch between the axes of a worm gear provided at the output axis of a drive motor fixed to a drive chassis via a motor holder and a worm wheel for power transmission which engages with the worm gear so as to have tolerance against gear skip or bottom contact between gears. <P>SOLUTION: At the corresponding position of the drive chassis 2 corresponding to one point on a line L passing through the axial center of the worm wheel 9a and orthogonal to the axis CL of the worm gear 10, a positioning means 12 of the motor holder 11 fixing the drive motor M is provided. Thus, even when the fitting direction of the drive motor M is deviated a little, the irregularity of the pitch P between the axes of the worm gear 10 and the worm wheel 9a is minimized in order to provide the tolerance against the gear skip or the bottom contact between the gears. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical disc apparatus that performs recording / reproduction on an optical disc such as a DVD or a CD, and in particular, a worm gear provided on an output shaft of a drive motor fixed to a drive chassis via a motor holder, and a power engaged with the worm gear. The present invention relates to an optical disc apparatus improved so as to suppress variations in inter-axis pitch with a worm wheel for transmission as much as possible.

  In a conventional general optical disk apparatus, a drive chassis on which an optical pickup and a turntable are mounted is attached to the main chassis so that the drive chassis can be turned up and down on both sides of the rear end, and a disk clamper is disposed above the turntable. The clamper support part is rotatably supported. When the optical disk is placed on the disk tray and fed between the turntable and the disk clamper, the drive chassis is rotated upward by the cam slider so that the central opening edge of the optical disk is sandwiched between the turntable and the disk clamper. While rotating the optical disc, the optical pickup is moved to irradiate the optical disc with a laser beam to perform recording / reproduction.

  In such an optical disc apparatus, the drive motor is fixed to the drive chassis directly or via a motor holder, and the worm gear is fixed to the output shaft of the drive motor, and the first worm wheel in the power transmission gear mechanism. The disc tray, the optical pickup, and the cam slider are operated via the power transmission gear mechanism.

  However, when the drive motor is fixed to the drive chassis via the motor holder, the number of parts increases by the amount of the motor holder, and the mounting direction of the drive motor changes depending on the backlash when the drive motor is mounted. The variation in the pitch between the shafts of the worm gear fixed to the output shaft of the motor and the worm wheel for power transmission meshing with the worm gear tends to increase, and thus the mounting direction (mounting angle) of the drive motor varies. Depending on the location of the motor holder, the pitch between shafts varies greatly, making it difficult to set tolerances when designing with gear skipping and tooth bottom contact between gears. There was a problem that the design would be difficult to use.

  On the other hand, as a worm gear device used for an electric power steering device of an automobile, a worm side housing that rotatably holds a worm shaft on which a worm is formed, and a worm wheel that rotatably holds a worm wheel that meshes with the worm. The side housings are fastened at their mating surfaces, and both housings are pivoted relative to each other about a pivot center axis parallel to the rotation axis of the worm wheel, so that the meshing position between the worm and the worm wheel can be adjusted. One is known (Patent Document 1).

As a motor with a speed reduction mechanism for an automobile power window, there is also known a motor in which a speed reduction mechanism including a worm fixed to the output shaft of a motor and a worm wheel meshing with the worm is accommodated in a case (Patent Document 2). ). In addition, the worm gear rotates around the rotation mounting part of the fulcrum of the worm chassis and is always pressed against the worm wheel side by the elastic force of the spring, even if the worm wheel, worm gear etc. change in eccentricity or tooth thickness, A backlash removing device is also known in which the distance between the axes is automatically adjusted by the elasticity of the spring (Patent Document 3).
JP 2001-271913 A JP 11-348555 A Japanese Patent Laid-Open No. 5-26330

  However, in the worm gear device of Patent Document 1, in order to make it possible to adjust the meshing position of the worm and the worm wheel, the turning central axes of both housings are orthogonal to the axis of the worm through the rotation axis of the worm wheel. When the worm axial direction is slightly changed, the inter-axis pitch between the worm and the worm wheel is greatly changed due to the provision at a position deviated to one side from the line. Therefore, even if the technology of the worm gear disclosed in Patent Document 1 is applied to the optical disc apparatus, it is not possible to suppress a change in the pitch between the shafts and to provide a large margin for tooth skipping between gears and tooth bottom contact.

  In addition, since the motor with a speed reduction mechanism of Patent Document 2 does not change the pitch between the worm and the worm wheel due to the change in the direction of the worm, there is no point in applying this technique to the optical disc apparatus. Further, the backlash removing device of Patent Document 3 is a fulcrum of the worm chassis so that the distance between the shafts can be automatically adjusted by the elasticity of the spring even if the worm wheel or worm gear changes in eccentricity or tooth thickness. The rotational mounting portion of the worm is provided at a position that is greatly deviated to one side from the line perpendicular to the axis of the worm gear through the shaft of the worm, so that the inter-axis pitch (inter-axis distance) between the worm and the worm wheel changes greatly. For this reason, even if the technology of this device is applied to the optical disk device, it is not possible to suppress a change in the pitch between the shafts and to provide a large margin for tooth skipping between gears and tooth bottom contact.

  The present invention has been made under the above circumstances, and the problem to be solved is a worm gear provided on an output shaft of a drive motor fixed to a drive chassis via a motor holder, and power transmission meshed with the worm gear. To provide an optical disc apparatus that can easily set tolerances at the time of design by minimizing the variation in the pitch between the shaft and the worm wheel for the purpose, and having allowance for tooth skipping and tooth bottom contact between gears. is there.

  In order to solve the above problems, the optical disc device according to the present invention is attached to the main chassis so that the drive chassis can be turned up and down on both sides of the rear end, and the drive motor is fixed to the drive chassis via a motor holder, In a disk device in which a worm gear is fixed to the output shaft of the drive motor and a worm wheel for power transmission meshing with the worm gear is rotatably mounted on the drive chassis, the disk device passes through the axis of the worm wheel and is orthogonal to the axis of the worm gear. A motor holder positioning means is provided at the corresponding position of the drive chassis corresponding to one point on the line.

  In the optical disc apparatus of the present invention, the corresponding position of the drive chassis corresponding to the intersection of the axis of the worm gear and the line orthogonal to the axis of the worm gear through the axis of the worm wheel, or the intersection on the orthogonal line It is preferable to provide positioning means for the motor holder at the corresponding position of the drive chassis corresponding to the vicinity of.

  Further, a preferred embodiment of the optical disk device of the present invention is such that the drive chassis is attached to the main chassis so as to be rotatable up and down on both sides of the rear end, and the drive motor is fixed to the drive chassis via a motor holder. In a disk device in which a worm gear is fixed to an output shaft of a drive motor and a worm wheel for power transmission meshing with the worm gear is rotatably mounted on a drive chassis, the worm gear passes through the axis of the worm gear and the axis of the worm wheel. A positioning hole is formed at the corresponding position of the drive chassis corresponding to the intersection with the line orthogonal to the axis, or at the corresponding position of the drive chassis corresponding to the vicinity of the intersection on the orthogonal line. The positioning protrusion of the motor holder is fitted in the hole. It is an feature.

  When the motor holder positioning means is provided at the corresponding position of the drive chassis corresponding to one point on the line orthogonal to the axis of the worm gear through the axis of the worm wheel as in the optical disk of the present invention, the motor holder When the drive motor is attached via the worm gear, even if the output motor direction (worm gear direction) deviates from a predetermined direction due to a slight rotation of the drive motor around the positioning means of the motor holder, the worm gear The change in the inter-axis pitch between the worm wheel and the worm wheel can be kept small, and the closer the position of the positioning means of this motor holder is to the axis of the worm wheel on the orthogonal line, the smaller the change in the inter-axis pitch becomes. Thus, when it overlaps with the axis of the worm wheel, the change in the inter-axis pitch becomes zero.

  Therefore, it is ideal to provide positioning means for the motor holder at the corresponding part of the drive chassis corresponding to the axis of the worm wheel, but in reality, the part corresponding to the axis of the worm wheel or the part overlapping the worm wheel. Since it is difficult to provide positioning means for the motor holder because of space, the corresponding position of the drive chassis corresponding to the intersection of the axis of the worm gear and the line perpendicular to the axis of the worm gear through the axis of the worm wheel, Alternatively, it is preferable to provide a motor holder positioning means at the corresponding position of the drive chassis corresponding to the vicinity of the intersection on the orthogonal line. The positioning means of the motor holder is not particularly limited, but the structure is simple if the positioning projection of the motor holder is fitted into the positioning hole formed in the drive chassis, as in the above-described more specific preferred optical disk device. There is an advantage that the motor holder can be positioned reliably.

  As described above, the optical disk apparatus according to the present invention includes the worm gear provided on the output shaft of the drive motor and the power engaged with the worm gear even if the mounting direction of the drive motor attached to the drive chassis via the motor holder is slightly deviated. Because variations in the pitch between the shaft and the worm wheel for transmission can be suppressed as much as possible, there is an effect that the margin for tooth skipping between gears and the contact with the bottom of the gear is increased, making it easier to set tolerances in the design. .

  Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic plan view showing an optical disk apparatus according to an embodiment of the present invention with a disk tray omitted, FIG. 2 is an enlarged bottom view of the optical disk apparatus, and FIG. 3 is a part where a drive motor is attached to the optical disk apparatus. FIG.

  As shown in FIG. 1, this optical disk apparatus has a drive chassis 2 attached to a main chassis 1 so as to be pivotable up and down by supporting shafts 2a, 2a on both sides of the rear end thereof. A turntable 3 is mounted on the front of the motor and is rotated by a spindle motor (not shown). A clamper 4 is disposed above the turntable 3 and is rotatably held by a clamper holding portion 5 a at the center of the bridge portion 5 that is horizontally mounted on the main chassis 1. A disc tray (not shown) is disposed between the turntable 3 and the clamper 4 and is attached to the inside of the main chassis 1 so as to be able to advance and retract.

  The drive chassis 2 is mounted so that the optical pickup 6 moves along the guide rod 7 in a direction approaching / separating from the turntable 4. The optical pickup 6 approaches the turntable 3. The optical disk is irradiated with a laser beam through the objective lens 6a. A cam slider 8 is slidably attached to the front edge portion of the main chassis 1, and an engagement protrusion 2 b at the front end of the drive chassis 2 is engaged with the cam groove of the cam slider 8. . When the cam slider 8 slides left and right, the engagement protrusion 2b moves in the cam groove so that the drive chassis 2 rotates in the vertical direction around the support shafts 2a and 2a on both sides of the rear end. It has become.

  Further, a drive motor M and a power transmission gear mechanism 9 are mounted on the back side of the drive chassis 2. The power transmission gear mechanism 9 includes a worm wheel 9a that meshes with a worm gear 10 fixed to an output shaft of the drive motor M, a pinion gear 9b that is integrally formed with the worm wheel 9a and meshes with a rack 6b of the optical pickup 6, and the worm A large gear 9d that meshes with a small gear 9c integrally formed with the wheel 9a, a middle gear 9e that meshes with the large gear 9d, a small gear 9f that meshes with the middle gear 9e, and a cam slider 8 that is integrally formed with the small gear 9f. The pinion gear 9g meshes with the rack 8a and the pinion gear 9h that is integrally formed with the small gear 9f and meshes with the rack of the disk tray (not shown), and the pinion gears 9g and 9h are integrally formed. Reference numeral 9 f is attached to the main chassis 1. The small gear 9f is disengaged from the middle gear 9e when the drive chassis 2 is lifted.

  As shown in FIGS. 2 and 3, the drive motor M is fixed to a motor holder 11 bent in an L shape with a stopper or the like, and is similarly attached to the back surface of the drive chassis 2 with the stopper or the like. The shaft end of the worm gear 10 fixed to the M output shaft is in contact with a stopper piece 2 c formed on the drive chassis 2. Then, as positioning means 12 for positioning and mounting the motor holder 11 to which the drive motor M is fixed at a predetermined position, a positioning hole 12a is formed in the drive chassis 2, and a positioning projection 12b fitted into the positioning hole 12a is provided as a motor holder. Further, as a means 13 for determining the mounting direction of the drive motor M, a slightly larger direction determining hole 13a is formed in the drive chassis 2, and a direction determining protrusion 13b that is loosely fitted in the direction determining hole is provided. It is protruding.

  As shown in FIG. 2, the positioning hole 12a constituting the positioning means 12 of the motor holder 11 passes through the axis of the worm wheel 9a and corresponds to one point on the line L perpendicular to the axis line CL of the worm gear 10. Corresponding positions of the drive chassis 2 corresponding to the vicinity of the intersection of the axis CL of the worm gear 10 and the orthogonal line L (the vicinity of the orthogonal line L) in this embodiment. The positioning projection 12b of the motor holder 11 is fitted in the positioning hole 12a formed at the corresponding location.

  When the positioning means 12 of the motor holder 11 is provided at the corresponding position of the drive chassis 2 corresponding to one point on the line L perpendicular to the axis line CL of the worm gear 10 through the axis of the worm wheel 9a. When the drive motor M is mounted via the motor holder 11, the drive motor M is slightly rotated around the positioning means 12 of the motor holder 11, so that the direction of the drive motor M (the direction of the worm gear 10) is predetermined. Even if the deviation occurs from the direction, it is possible to suppress the change in the inter-axis pitch between the worm gear 10 and the worm wheel 9a. The closer the position of the positioning means 12 of the motor holder 11 is to the axis of the worm wheel 9a on the perpendicular line L, the smaller the change in the inter-axis pitch P between the worm gear 10 and the worm wheel 9a. When it overlaps with the axis of the wheel 9a, the change in the inter-axis pitch P becomes zero.

  Therefore, it is ideal to provide the positioning means 12 of the motor holder 11 at the corresponding portion of the drive chassis 2 corresponding to the axis of the worm wheel 9a. Since it is difficult to provide the positioning means 12 of the motor holder 11 at a position overlapping the wheel 9a because of space, in this embodiment, as described above, the position near the intersection with the line L perpendicular to the axis CL of the worm gear 10 Positioning means 12 is provided at the corresponding position of the drive chassis 2 corresponding to the above. Similarly, it is also preferable to provide the positioning means 12 at the corresponding position of the drive chassis 2 corresponding to the intersection point of the line L perpendicular to the axis CL of the worm gear 10.

  In the state of FIG. 1 in which the drive chassis 2 is lowered, the optical disk apparatus having the above-described configuration transmits the power of the drive motor M to the pinion gear 9h that meshes with the rack of the disk tray of the power transmission gear mechanism 9. Is inserted between the turntable 3 and the clamper 4, the pinion gear 9g and the rack 8a of the cam slider 8 mesh with each other, and the cam slider 8 moves to the left. Rotating upward about the support shafts 2a, 2a on both sides of the rear, the turntable 3 and the clamper 4 chuck the center opening edge of the optical disc, and the optical disc rotates. Then, the optical pickup 6 irradiates the optical disk with the laser beam through the objective lens 6a while moving in the direction approaching the turntable 3 by the pinion gear 9b meshing with the rack 6b, and recording / reproduction is performed. When the recording / reproduction is completed, the optical disk is placed on the disk tray and taken out of the apparatus by the reverse operation.

  As described above, this optical disk apparatus transmits the power of the drive motor M from the worm 10 fixed to the output shaft to the first worm wheel 9 a of the power transmission gear mechanism 9, and through this power transmission gear mechanism 9. As described above, the positioning means 12 of the motor holder 11 for fixing the drive motor M is passed through the shaft core of the worm wheel 9a as described above. The corresponding position of the drive chassis 2 corresponding to one point on the line L orthogonal to the ten axis CL (in this embodiment, the vicinity of the intersection of the orthogonal line L and the axis CL of the worm gear on the orthogonal line L Of the motor holder 11 for fixing the drive motor M by being provided at the corresponding position of the drive chassis 2 corresponding to Since the change in the inter-axis pitch P between the worm gear 10 and the worm wheel 9a due to the deviation of the direction is suppressed as small as possible, the margin for tooth skipping and tooth bottom contact between the worm gear 10 and the worm wheel 9a increases. A remarkable effect is obtained such that the tolerance setting at the time of designing becomes easy.

1 is a schematic plan view showing an optical disc apparatus according to an embodiment of the present invention with a disc tray omitted. It is an expanded partial bottom view of the same optical disk device. It is an enlarged view of the part which attached the drive motor of the optical disk device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main chassis 2 Drive chassis 2a Support shaft part 3 Turntable 4 Clamper 6 Optical pick-up 8 Cam slider 9 Power transmission gear mechanism 9a Worm wheel 10 Worm gear 11 Motor holder 12 Motor holder positioning means 12a Positioning hole 12b Positioning protrusion M Drive motor CL Worm gear axis L L A line passing through the worm wheel axis and perpendicular to the worm gear axis P Pitch between worm gear and worm wheel

Claims (3)

The drive chassis is mounted on the main chassis so that the drive chassis can be turned up and down on both sides of the rear end. The drive motor is fixed to the drive chassis via a motor holder, and the worm gear is fixed to the output shaft of the drive motor and meshed with the worm gear. In a disk device in which a worm wheel for power transmission is rotatably mounted on a drive chassis,
Corresponding position of the drive chassis corresponding to the intersection of the axis of the worm gear and the line passing through the axis of the worm wheel and perpendicular to the axis of the worm gear, or the drive chassis corresponding to the vicinity of the intersection on the orthogonal line The disk device is characterized in that a positioning hole is formed at the corresponding position, and a positioning projection of the motor holder is fitted into the positioning hole. The drive chassis is mounted on the main chassis so that the drive chassis can be turned up and down on both sides of the rear end. The drive motor is fixed to the drive chassis via a motor holder, and the worm gear is fixed to the output shaft of the drive motor and meshed with the worm gear. In a disk device in which a worm wheel for power transmission is rotatably mounted on a drive chassis,
A disk device comprising: a motor holder positioning means at a corresponding position of a drive chassis corresponding to a point on a line orthogonal to the axis of the worm gear through an axis of the worm wheel. Corresponding position of the drive chassis corresponding to the intersection of the axis of the worm gear and the line passing through the axis of the worm wheel and perpendicular to the axis of the worm gear, or the drive chassis corresponding to the vicinity of the intersection on the orthogonal line A disk device characterized in that positioning means for the motor holder is provided at the corresponding position.

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