JP2005116010A - Disk drive - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reliably maintain a state of skew being adjusted while reducing the dimensions of a disk drive. <P>SOLUTION: This drive has: a reference plane 35a of the base 11, perpendicular to the optical disk 2 loaded on a disk table 15; an adjust screw 34 to move the guide shaft 18 along the reference plane 35a; and a coil spring 37 whose one arm 37b extending from a coil part 37a forms a fixing part 38 to be fixed to the base 11 and the other arm 37c extending from the coil part 37a forms a pressing section 39 to press the guide shaft 18 against the reference plane 35a. By adjusting the screw 34 to move the guide shaft 18 along the reference plane 35a, the optical axis L of the light beam 3 emitted from the optical pickup 13 supported by the guide shaft 18 is made to be perpendicular to the optical disk 2 loaded on the disk table 15. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a disk drive device including a skew adjustment mechanism that can adjust the optical axis of a light beam emitted from an optical pickup perpendicular to a signal recording surface of an optical disk.

  In an optical disc on which information signals are recorded with high density, the optical axis of the light beam emitted from the optical pickup is inclined rather than perpendicular to the signal recording surface of the optical disc mounted on the disc table of the disc rotation drive mechanism. As a result, aberrations occur and accurate information signals cannot be recorded or reproduced. Therefore, in a disk drive device that uses an optical disk capable of recording information signals at high density as a recording medium, the optical axis of the light beam emitted from the optical pickup is the signal of the optical disk mounted on the disk table of the disk rotation drive mechanism. Some are provided with a skew adjustment mechanism that adjusts perpendicularly to the recording surface. Adjustment using the skew adjustment mechanism is usually performed at the manufacturing stage of the disk drive device.

  As this kind of skew adjustment mechanism, there is one as shown in Patent Document 1. Specifically, the skew adjustment mechanism disclosed in Patent Document 1 includes a coil spring that biases each end portion of the main guide shaft of the optical pickup in the optical axis direction of the optical pickup, and a mechanical chassis that is orthogonal to the end surface of the main guide shaft. The main guide shaft is brought into contact with the stopper surface in cooperation with the coil spring and the stopper surface provided on the mechanical chassis so as to be orthogonal to the main surface, and the position and the inclination of the main guide shaft in the optical axis direction are adjusted. A skew adjustment screw for adjustment, and the skew adjustment screw and the skew adjustment screw so that the main guide shaft is in contact with the stopper surface and the adjusted position and inclination of the main guide shaft are held by the skew adjustment screw. And a female screw portion.

  In this skew adjustment mechanism, the skew adjustment screw and the coil spring cooperate to bring the guide shaft into contact with the stopper surface provided on the mechanical chassis and adjust the position and inclination of the guide shaft. In spite of the simple configuration, the positioning of the main guide shaft in the tangential direction and the skew adjustment can be reliably performed, and good optical characteristics can be obtained. However, since the skew adjustment mechanism of Patent Document 1 uses a coil spring as an urging member, the space efficiency is low and it is difficult to reduce the size.

  As a skew adjustment mechanism of the same kind, there is one as shown in Patent Document 2. The skew adjustment mechanism disclosed in Patent Document 2 supports a leaf spring that urges the small diameter portion of the end portion of the sub guide shaft in the optical axis direction of the laser light irradiated from the optical pickup, and the sub guide shaft via the leaf spring. The slot that is formed in the mechanical chassis that restricts the movement of the sub guide shaft in the tangential direction, and the position and inclination of the sub guide shaft in the optical axis direction of the optical pickup are adjusted against the biasing force of the leaf spring And a female screw portion formed in a mechanical chassis that is screwed to the skew adjustment screw.

  In this skew adjustment mechanism, two functions, that is, a function of urging the sub guide shaft substantially in the optical axis direction of the optical pickup and a function of restricting movement of the guide shaft in the axial direction (thrust direction) Since it is realized by a spring, the number of components can be reduced and the structure can be simplified, and the productivity of the apparatus can be improved. However, the skew adjustment mechanism of Patent Document 2 uses a leaf spring as the urging member, and is not durable. Therefore, the spring force of the leaf spring is weakened over a long period of time, and the adjusted skew may come.

JP 2002-15434 A JP 2002-42432 A

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a disk drive device that can be reduced in size and stably maintained in a state in which the skew is adjusted. is there.

  A disk drive apparatus according to the present invention irradiates a light beam to a base, a disk rotation driving mechanism provided on the base and rotating the optical disk, and an optical disk provided on the base and rotated by the disk rotation driving mechanism. An optical pickup for detecting a return light beam reflected by an optical disc, a guide mechanism having a guide shaft that supports the optical pickup so as to be movable in the radial direction of the optical disc mounted on the disc rotational drive mechanism, and a disc rotational drive mechanism. A skew adjusting mechanism for adjusting the inclination of the guide shaft so that the optical axis of the light beam emitted from the optical pickup is perpendicular to the mounted optical disc. The skew adjustment mechanism is based on a reference plane perpendicular to the optical disk mounted on the disk rotation drive mechanism, an adjustment screw for moving the guide shaft along the reference plane, and one arm extending from the coil section. The other arm extending from the coil portion is a torsion coil spring serving as a pressing portion that presses the guide shaft against the reference surface. This skew adjustment mechanism advances and retracts the adjustment screw, moves the reference surface and the guide shaft pressed against the tip of the adjustment screw by the pressing portion of the torsion coil spring along the reference surface, and is supported by the guide shaft. The optical axis of the light beam emitted from the optical disk can be adjusted to be perpendicular to the optical disk mounted on the disk rotation drive mechanism.

  According to the present invention, it is possible to adjust the inclination of the guide shaft by advancing and retracting the adjustment screw in a state where the end of the guide shaft is pressed against the reference surface and the end surface of the adjustment screw using the torsion coil spring. Since this torsion coil spring is superior in durability to a leaf spring or the like, the state after skew adjustment can be maintained over a long period of time.

  An optical disk drive device to which the present invention is applied will be described below with reference to the drawings. As shown in FIGS. 1 and 2, an optical disk drive device 1 to which the present invention is applied has a base 11, a disk rotation drive mechanism 12 that rotates the optical disk 2, and the disk rotation drive mechanism 12. An optical pickup 13 is provided for irradiating the optical disc 2 mounted on the optical disc 2 with a light beam and detecting the return light beam reflected by the optical disc 2.

  The disk rotation drive mechanism 12 is arranged such that a spindle motor 14 serving as a rotation drive source of the optical disk 2 projects a drive shaft 14a toward one main surface of the base 11, and the drive shaft 14a includes: A disk table 15 on which an optical disk 2 for recording and reproducing information signals is mounted is integrally attached. The disc table 15 is provided with a centering portion 15a for engaging the center hole 2a of the optical disc 2 to center the optical disc 2, and a disc receiving portion 15b for receiving the optical disc 2 is provided around the centering portion 15a. It has been. When the optical disk 2 is mounted with the center hole 2a engaged with the centering portion 15a, the disk table 15 rotates the mounted optical disk 2, for example, at a constant linear velocity.

  An optical pickup 13 that emits a light beam to the signal recording surface of the optical disk 2 mounted on the disk table 15 condenses a light beam of a predetermined wavelength emitted from a semiconductor laser inside the optical disk 2 by using an objective lens 16. An optical system is provided that detects the return light beam irradiated to the signal recording surface and reflected by the signal recording surface of the optical disc 2 with a photodetector. The objective lens 16 is held by a biaxial actuator, and the biaxial actuator displaces the objective lens 16 in the direction of the optical axis of the light beam based on the focusing servo signal, and based on the tracking error signal. Thus, the drive displacement is performed in a direction perpendicular to the recording track of the optical disc 2.

  The optical pickup 13 as described above is movably attached by a guide mechanism 17 for moving in the radial direction of the optical disc 2 mounted on the disc table 15. The guide mechanism 17 has a pair of guide shafts 18 and 18 parallel to each other along the radial direction of the optical disc 2 mounted on the disc table 15. The pair of guide shafts 18 and 18 supports both ends of the optical pickup 13 so as to be linearly movable. The guide shaft 18 is formed with a thin end portion of a main shaft portion 18 a that supports the optical pickup 13, and serves as an attachment shaft portion 18 b for attachment to the base 11. The optical pickup 13 is provided with a pair of support pieces 19, 19 at each end, and the pair of support pieces 19, 19 provided at each end has shaft holes 21, 21 whose axes are aligned. Is formed. The optical pickup 13 is configured such that the main shaft portion 18a of the guide shafts 18 and 18 is inserted into the shaft holes 21 and 21, so that the optical pickup 13 is guided by the guide shafts 18 and 18 and slides while being mounted on the disk table 15. Move in the radial direction. The objective lens 16 of the optical pickup 13 movably supported by the guide mechanism 17 is exposed to the outside from the opening 22 formed in the base 11.

  Although not shown, the optical pickup 13 supported by the guide mechanism 17 is mounted on the disk table 15 while being guided by the guide mechanism 17 by a feed screw connected to a drive source such as a stepping motor. The optical disk 2 moves in the radial direction.

  By the way, as shown in FIG. 2, in the optical disc drive apparatus 1, the signal of the optical disc 2 is collected without causing aberration in the light beam focused on the objective lens 16 of the optical pickup 13 and irradiated on the signal recording surface of the optical disc 2. Therefore, the optical axis L of the light beam 3 emitted from the optical pickup 13 needs to be perpendicular to the signal recording surface of the optical disc 2. Therefore, the optical disc drive apparatus 1 is provided with a skew adjustment mechanism 31 for adjusting the inclination of the optical axis L of the light beam 3 as shown in FIGS. As shown in FIG. 1, the skew adjusting mechanism 30 is provided at each end of the pair of guide shafts 18 and 18. Since these four skew adjustment mechanisms 31 have the same configuration, only one will be described as an example.

  As shown in FIG. 3, the skew adjustment mechanism 31 includes an attachment piece 32 that is formed near the opening 22 of the base 11 and to which the guide shaft 18 is attached. As shown in FIG. 3, the attachment piece 32 is a piece integral with the base 11 formed by cutting and raising the base 11, and a bent piece bent on the other surface side of the base 11. 32a, a parallel piece 32b parallel to the main surface of the base 11, and a vertical piece 32c perpendicular to the main surface of the base 11, that is, perpendicular to the signal recording surface of the optical disk 2 mounted on the disk table 15. It consists of

  An adjustment hole 33 for adjusting the inclination of the guide shaft 18 is formed in the parallel piece 32b. The adjustment hole 33 is a screw hole to which an adjustment screw 34 such as a set screw with a hole that is an adjustment member for adjusting the inclination of the guide shaft 18 is attached. The adjustment screw 34 is formed such that a tip end surface serving as an insertion end forms a substantially arcuate surface 34a.

  The vertical piece 32 c is formed so as to be perpendicular to the main surface of the base 11, that is, perpendicular to the signal recording surface of the optical disc 2 mounted on the disc table 15. The vertical piece 32c is formed so that its main surface faces the moving direction of the optical pickup 13. The vertical piece 32c is formed with a mounting hole 35 to which a mounting shaft 18b which is an end of the guide shaft 18 is mounted. The attachment hole 35 is formed of a substantially rectangular long hole formed so that its long side is perpendicular to the signal recording surface of the optical disk 2 mounted on the disk table 15, and restricts the movement amount of the guide shaft 18. To do. The end surface of one long side of the mounting hole 35 becomes a reference surface 35a against which the peripheral surface of the mounting shaft 18b of the guide shaft 18 is abutted. Further, the short side of the mounting hole 35 is formed to be substantially the same as the diameter of the mounting shaft 18 b of the guide shaft 18, and a lateral backlash parallel to the signal recording surface of the optical disk 2 mounted on the disk table 15. Prevents sticking. In addition, it is a base end part of the attachment shaft part 18b, and the end surface of the main shaft part 18a becomes an abutting part that is abutted around the attachment hole 35 when the attachment shaft part 18b is inserted into the attachment hole 35.

  The vertical piece 32c is formed such that a gap 36 is provided between the vertical piece 32c and the bent piece 32a. A torsion coil spring 37 is disposed in the gap 36. The torsion coil spring 37 includes a coil part 37a disposed in the gap 36 and a pair of arm parts 37b and 37c extending from the coil part 37a. One arm portion 37b is bent in a substantially C shape and serves as a fixing portion 38 for fixing to the parallel piece 32b. The other arm portion 37c serves as a pressing portion 39 for pressing the mounting shaft portion 18b of the guide shaft 18 inserted through the mounting hole 35 by the pressing force F in the rewinding direction. The torsion coil spring 37 serving as the biasing member is fixed such that the coil portion 37a is inserted into the gap 36, and the fixing portion 38 of one arm portion 37c is sandwiched between the parallel piece 32b with the coil portion 37a, and the other arm The pressing portion 39 of the portion 37 c presses the mounting shaft portion 18 b of the guide shaft 18 inserted into the mounting hole 35 against the reference surface 35 a of the mounting hole 35 and the tip end portion of the adjusting screw 34 screwed into the adjusting hole 33. Attached to.

  The skew adjustment mechanism 31 configured as described above is used for skew adjustment after components such as the disk table 15, the optical pickup 13, and the guide shaft 18 are attached to the base 11. That is, as shown in FIG. 4, when components such as the disk table 15, the optical pickup 13, and the guide shaft 18 are attached to the base 11, an adjustment screw 34 is attached to the adjustment hole 33 of the parallel piece 32b. Yes. The torsion coil spring 37 is fixed so that the coil portion 37a is inserted into the gap 36, the fixing portion 38 of one arm portion 37c is sandwiched between the parallel piece 32b and the coil portion 37a, and the other arm portion 37c is pressed. The part 39 is attached so as to press the attachment shaft part 18b of the guide shaft 18 inserted into the attachment hole 35c against the reference surface 35a of the attachment hole 35 and the tip of the adjustment screw 34 screwed into the adjustment hole 33. Even in the state shown in FIG. 4, the pressing portion 39 of the torsion coil spring 37 causes the mounting shaft portion 18 b of the guide shaft 18 to move from the reference surface 35 a of the mounting hole 35 and the adjustment hole 33 by the pressing force F in the rewinding direction. Is pressed against the tip of the adjustment screw 34 that is screwed onto the screw. Here, the adjustment screw 34 has a tip surface formed by a substantially arc surface 34 a, and the mounting shaft portion 18 b of the guide shaft 18 pressed by the pressing portion 39 of the torsion coil spring 37 on the substantially arc surface 34 a, The mounting hole 35 is pressed against the reference surface 35a.

  In this state, the optical disk drive 1 is loaded with the adjustment optical disk 2 used for focusing, tracking, skew adjustment, etc. on the disk table 15, and recording and reproduction operations are performed. The individual skew adjustment is performed by moving the adjustment screw 34 forward and backward so that the output value becomes an optimum value at which the aberration becomes zero while observing the output value from the optical pickup 13. For example, as shown in FIG. 5, when the mounting shaft portion 18 b of the guide shaft 18 is moved in the direction of arrow D in FIG. 5 to be close to the base 11, the pressing force F of the pressing portion 39 of the torsion coil spring 37 is resisted. By pushing the adjustment screw 34 forward, the mounting shaft portion 18b of the guide shaft 18 can be moved in the direction of arrow D in FIG. 5 adjacent to the base 11 while being pressed against the reference surface 35a of the mounting hole 35.

  The skew adjustment mechanism 31 is provided at each end of the guide shaft 18 as shown in FIG. Therefore, the skew adjustment is performed using the skew adjustment mechanism 31 provided at each end of the guide shaft 18 in the directions indicated by the arrow D and the counter arrow D in FIGS. Will be done. Further, the optical disc drive apparatus 1 uses the skew adjustment mechanism 31 provided at each end of the guide shaft 18 to move the entire guide shaft 18 in the direction of approaching and separating from the base 11, thereby focusing. Coarse adjustment can also be performed.

  In the skew adjustment mechanism 31 as described above, the mounting shaft portion 18b of the guide shaft 18 abuts against the two points of the tip surface of the adjustment screw 34 and the reference surface 35a of the mounting hole 35. Thus, accurate skew adjustment can be performed by moving the adjustment screw 34 back and forth. Further, the skew adjusting mechanism 31 uses the torsion coil spring 37 instead of the leaf spring as the urging member, so that the durability is improved and the skew adjustment state can be maintained for a long time. Further, the skew adjusting mechanism 31 has the mounting piece 32 formed integrally with the base 11, so that the number of parts can be reduced and the optical disc drive apparatus 1 can be downsized.

  The skew adjustment mechanism 31 may be configured as shown in FIG. That is, in the skew adjustment mechanism 31 shown in FIG. 6, the insertion piece 41 into which the coil portion 37 a of the torsion coil spring 37 is inserted is formed integrally with the bent piece 32 a of the attachment piece 32. The torsion coil spring 37 is prevented from shifting its mounting position by inserting the coil portion 37a into the insertion piece 41 formed in the bent piece 32a. As shown in FIG. 6, the reference surface 35a against which the mounting shaft portion 18b of the guide shaft 18 is abutted is the end surface of one long side of the mounting hole 35 formed in the vertical piece 32c, and the rising piece 42 These side surfaces may be used as the reference surface 42a. Further, the rising piece 42 serves as a restricting portion 42b that bends the tip side and restricts the amount of movement of the guide shaft 10.

  In the above example, the case where the attachment piece 32 constituting the skew adjustment mechanism 31 is formed integrally with the base 11 has been described. However, in the present invention, the attachment piece 32 may be a separate member from the base 11. .

It is a top view of the optical disk drive device to which the present invention is applied. 1 is a side view of an optical disk drive device to which the present invention is applied. It is a disassembled perspective view of a skew adjustment mechanism. It is a side view explaining the state of the skew adjustment mechanism before skew adjustment. It is a side view explaining the state of the skew adjustment mechanism after skew adjustment. It is a perspective view explaining the modification of a skew adjustment mechanism.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical disk drive device, 11 Base, 12 Disk rotation drive mechanism, 13 Optical pick-up, 15 Disk table, 16 Objective lens, 18 Guide shaft, 19 Support piece, 21 Shaft hole, 22 Opening part, 31 Skew adjustment mechanism, 32 Mounting piece 32b Parallel piece, 32c Vertical piece, 33 Adjustment hole, 34 Adjustment screw, 34a Arc surface, 35 Mounting hole, 35a Reference surface, 36 Gap, 37 Torsion coil spring, 38 Fixed part, 39 Press part

Claims (3)

Base and
A disk rotation drive mechanism provided on the base for rotating the optical disk;
An optical pickup that is provided on the base and that irradiates the optical disk rotated by the disk rotation driving mechanism and detects a return light beam reflected by the optical disk;
A guide mechanism having a guide shaft that supports the optical pickup so as to be movable in a radial direction of an optical disk mounted on the disk rotation driving mechanism;
A skew adjusting mechanism that adjusts the inclination of the guide shaft so that the optical axis of the light beam emitted from the optical pickup is perpendicular to the optical disk mounted on the disk rotation driving mechanism;
The skew adjustment mechanism includes a reference surface perpendicular to the optical disk mounted on the disk rotation drive mechanism, an adjustment screw for moving the guide shaft along the reference surface, and one arm extending from the coil portion. Has a torsion coil spring that becomes a fixed portion fixed to the base and the other arm extending from the coil portion serves as a pressing portion that presses the guide shaft against the reference surface,
The optical disk of the light beam emitted from the optical pickup supported by the guide shaft is moved to move the guide shaft along the reference plane by moving the adjustment screw back and forth, and the optical disk mounted on the disk rotation driving mechanism. Disk drive that can be adjusted to be perpendicular to the drive.   The disk drive device according to claim 1, wherein the coiled portion of the torsion coil spring is inserted into an insertion piece of the base.   The disk drive device according to claim 1, wherein the skew adjusting mechanism is provided at each end of the guide shaft.

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