JP4770480B2 - Optical pickup moving mechanism and disk recording and / or reproducing apparatus including the same - Google Patents

Description

The present invention relates to a moving mechanism including a mechanism for removing backlash in a gear block when the optical pickup is moved through a gear block including a plurality of gear trains, and a disc recording and / or reproducing apparatus including the moving mechanism.

  2. Description of the Related Art An optical disk recording / reproducing apparatus is provided with a disk rotation driving mechanism that rotates an optical disk, and an optical pickup that irradiates the optical disk with a light beam and detects a return light beam reflected by the optical disk. Since this optical pickup needs to be fed in the radial direction of the optical disk, it is attached to the moving mechanism. This moving mechanism includes a mechanism in which a rack to which an optical pickup is attached and a drive motor are connected by a reduction gear block. In this moving mechanism, when the drive motor rotates forward or reversely, the optical pickup is sent in the radial direction of the optical disc via the reduction gear block.

  The moving mechanism provided with such a gear block is provided with a backlash removing mechanism for removing the backlash of the gear train constituting the gear block. For example, the backlash removal mechanism is configured to derail the gear train by pulling the rack in one direction by a pulling coil spring.

  By the way, the tension coil spring generally has a larger load as the amount of deflection, that is, in the axial direction, is extended. Therefore, when a tension coil spring is used for the backlash mechanism, the degree of extension of the tension coil spring differs depending on the position of the optical pickup, resulting in fluctuations in the load applied to each gear constituting the gear block. The load applied to the motor fluctuates and the drive control becomes complicated.

JP 2000-306344 A

The present invention has been made in view of the above-described problems, and its purpose is to eliminate the fluctuation of the load on the drive source while keeping the load on the gear block constant when removing the backlash of the gear block. It is an object of the present invention to provide an optical pickup moving mechanism and a disk recording and / or reproducing apparatus including the same.

Another object of the present invention is to provide an optical pickup moving mechanism that can realize a backlash mechanism with a simple configuration, and a disk recording and / or reproducing apparatus including the moving mechanism.

The moving mechanism according to the present invention includes a first rack to which an optical pickup is attached and moved relative to a base, a driving source for moving the optical pickup, and the driving source and the first by a plurality of gear trains. A gear block that couples to the rack, and a backlash removal mechanism that removes the backlash of the gear block. The backlash removal mechanism includes a slider that slides relative to the base in the same direction as the first rack, a second rack provided on the base, and the first rack and the base that are attached to the slider. A connecting gear for connecting the second rack, and a load applying member that has one end attached to the base and the other end attached to the slider and applies a constant load to the slider. The connecting gear for connecting the first rack and the second rack is a two-stage gear, and the load applying member is a constant looping between the base and the slider in a state where the coil spring is always curved. It is a force spring.

The disk recording and / or reproducing apparatus according to the present invention is also provided for a base, a disk rotation driving mechanism that is provided on the base and rotates an optical disk mounted thereon, and an optical disk rotated by the disk rotation driving mechanism. An optical pickup for irradiating a light beam and detecting a return light beam reflected by the optical disk, a pickup base provided with the optical pickup, and the pickup base in the radial direction of the optical disk mounted on the disk rotation drive mechanism And a moving mechanism that moves. The movement mechanism includes a first rack provided on the pickup base, a drive source for moving the pickup base, and a gear block that connects the drive source and the first rack by a plurality of gear trains. And a backlash removing mechanism for removing the backlash of the gear block. The backlash removal mechanism includes a slider that slides relative to the base in the same direction as the first rack, a second rack provided on the base, and the first rack and the base that are attached to the slider. A connecting gear for connecting the second rack, and a load applying member that has one end attached to the base and the other end attached to the slider and applies a constant load to the slider. The connecting gear for connecting the first rack and the second rack is a two-stage gear, and the load applying member is a constant looping between the base and the slider in a state where the coil spring is always curved. It is a force spring.

  According to the present invention, since the load application member having a constant load is used for the backlash removal mechanism, the load to the gear block is constant, and the load fluctuation to the drive source can be eliminated. It can be done easily.

  A disk recording / reproducing apparatus to which the present invention is applied will be described below with reference to the drawings.

    This disk recording / reproducing apparatus is an optical disk recording / reproducing apparatus such as a compact disk or a digital versatile disk on which data such as music data, video data, and map data is recorded.

  As shown in FIG. 1, the disk recording / reproducing apparatus 10 is provided with a disk rotation drive mechanism 12 for rotating an optical disk 1 on a base 11 formed by bending a metal plate, for example.

  As shown in FIG. 1, the disk rotation driving mechanism 12 that rotates the optical disk 1 has a disk table 13 on which the optical disk 1 is mounted. The disk table 13 is attached to a spindle 15 of a spindle motor 14 attached to the back surface of the base 11 and rotates integrally with the spindle 15. The disk rotation drive mechanism 12 is, for example, a servo control that changes the optical disk 1 to CLV (Constant Linear Velocity), CAV (Constant Angula Velocity), ZCLV (Zone Constant Linear Velocity), ZCAV (Zone Constant Angular Velocity), or the like. Rotate while doing.

  The base 11 is provided with an optical pickup 16. The optical pickup 16 faces outward from an opening 17 provided in the base 11 over the radial direction of the optical disc 1 mounted on the disc table 13. The optical pickup 16 condenses and irradiates the optical beam 1 emitted from the light source to the optical disk 1 rotated by the disk table 13 by the objective lens 16a, and returns the return light beam reflected by the optical disk 1 to the light. By detecting with the detector, data is written to the optical disc 1 while controlling tracking servo, focusing servo, etc., and data recorded on the optical disc 1 is read.

  The optical pickup 16 is attached to the pickup base 18 and is linearly fed in the radial direction of the optical disc 1 that is rotatably supported by the disc table 13 through the opening 17 by the moving mechanism 21. The moving mechanism 21 for feeding the optical pickup 16 in the radial direction of the optical disk 1 is supported at one end by inserting a guide shaft 22 fixed to the base 11 into a guide hole 19 formed in the pickup base 18. In addition, although not shown, the optical pickup 16 is supported so as to be linearly movable in the radial direction of the optical disc 1 by engaging an engaging piece of the pickup base 18 with a guide groove formed in the base 11 at the other end. Yes. Note that the moving mechanism 21 may be movably supported at both ends by a pair of guide shafts parallel to each other.

  Further, as shown in FIG. 2, the moving mechanism 21 uses a drive motor 23 as a drive source for moving the optical pickup 16. Further, the moving mechanism 21 connects the first rack 24 provided on the pickup base 18 and the drive motor 23 with a reduction gear block 25. As shown in FIG. 2, the reduction gear block 25 includes first to third intermediate gears 26, 27, 28, a worm 29 attached to the spindle of the drive motor, and a first base provided on the pickup base 18. And a drive gear 31 connected to the rack 24.

  Each of the first to third intermediate gears 26, 27, and 28 is a two-stage gear, the large diameter gear portion 26a of the first intermediate gear 26 is connected to the worm 29, and the small diameter gear portion 26b is The second intermediate gear 27 is connected to the large-diameter gear portion 27a. The small diameter gear portion 27 b of the second intermediate gear 27 is connected to the large diameter gear portion 28 a of the third intermediate gear 28, and the small diameter gear portion 28 b of the third intermediate gear 28 is connected to the drive gear 31. The When the drive motor 23 is driven, the drive gear 31 is rotated through the first to third intermediate gears 26, 27, and 28, so that the drive gear 31 is connected to the first rack 24. The pickup base 18 moves linearly.

  By the way, in this moving mechanism 21, as shown in FIG. 2, the driving force of the drive motor 23 is transmitted to the pickup base 18 by the reduction gear block 25 comprising a plurality of gears. Backlash is generated by the play of the respective positions where the gears that mesh with each other mesh with each other. Therefore, the moving mechanism 21 is provided with a backlash removing mechanism 32 for removing the backlash of the reduction gear block 25 so that the position control of the optical pickup 16 can be accurately performed.

  The backlash removal mechanism 32 includes a slider 33 slidably attached to the base 11, a second rack 34 provided on the base 11, a first rack 24 of the pickup base 18 provided on the slider 33, and a first rack 24 of the base 11. A connecting gear 35 that connects the two racks 34 and a constant force spring 36 that serves as a load applying member that biases the slider 33 in one direction.

  The slider 33 is formed with guide holes 33a and 33a so as to be slidable in the same direction as the movement direction of the pickup base 18, and guide protrusions 33b and 33b formed on the base 11 are engaged with the guide holes 33a and 33a. ing. A second rack 34 is formed integrally with the base 11 so as to be spaced apart in parallel with the sliding direction of the slider 33.

  The connection gear 35 is a two-stage gear, and is rotatably attached to a support shaft 37 formed on the slider 33. The connection gear 35 uses a two-stage gear, that is, the large diameter gear portion 35 a is connected to the first rack 24 of the pickup base 11, and the small diameter gear portion 35 b is connected to the second rack 34 of the base 11. Thus, the first rack 24 and the second rack 34 are brought close to each other so that the size can be reduced. Further, by connecting the first rack 24 and the second rack 34 with the connecting gear 35, the sliding amount of the slider 33 can be reduced and the backlash mechanism can be downsized.

  The slider 33 is applied with a load by a constant force spring 36 and is urged in one direction. The constant force spring 36 is configured such that one end of the coil spring is freely locked to the locking projection 36a of the base 11 and the other end is freely locked to the locking projection 36b of the slider 33 so as to be bent as a whole. It is attached. As shown in FIG. 3, the constant force spring 36 that is stretched between the base 11 and the slider 33 in this way is a normal tension coil spring (line wire) that increases in load as the amount of deflection increases. Compared to 38a), the load is substantially constant, that is, does not change even if the amount of deflection changes until both ends reach parallel positions (line 38b). Therefore, the constant force spring 36 can urge the slider 33 in one direction (the direction of arrow P in FIG. 2) with substantially the same load.

  As described above, the rotation support member 41 straddles the base 11 as shown in FIG. 1 on the base 11 on which the disc table 13, the optical pickup 16, and the moving mechanism 21 of the optical pickup 16 are disposed. It is attached so that rotation is possible. That is, the base 11 is formed with a pair of support pieces 42 and 42 on the base end side, and shaft holes 42a and 42a are formed in the support pieces 42 and 42, respectively. The rotation support member 41 is formed with rotation shafts 43 and 43 corresponding to the pair of support pieces 42 and 42 on the base 11 side. The rotation shafts 43 and 43 are not formed inward of each other, but are formed in the same direction. Therefore, the rotation support member 41 can be attached by sliding the rotation shafts 43, 43 into the shaft holes 42 a, 42 a formed in the support pieces 42, 42 of the base 11.

  A disc pressing plate 44 that sandwiches the optical disc 1 with the disc table 13 is rotatably attached to the middle of the rotation support member 41. The disk holding plate 44 constitutes the disk rotation drive mechanism 12 together with the disk table 13, and is rotatably attached to the middle of the rotation support member 41. As described above, the rotation support member 41 to which the disk pressing plate 44 is attached has the operation projection 45 formed on one side surface thereof, and rotates with respect to the base 11 so that the disk pressing plate 44 is moved to the disk table 13. It is possible to be close to and away from.

  In the disc recording / reproducing apparatus 10 configured as described above, when the optical disc 1 is mounted on the disc table 13 by being engaged with the center hole 1 a of the optical disc 1, the rotation support member 41 approaches the base 11. The optical disk 1 is sandwiched between the disk table 13 and the disk pressing plate 44, and the optical disk 1 is rotated integrally with the disk table 13. In the disc recording / reproducing apparatus 10, the optical pickup 16 collects and irradiates the optical beam 1 emitted from the light source with the objective lens 16 a onto the optical disc 1 rotated by the disc table 13. By detecting the reflected return light beam with a photodetector, data is written to the optical disc 1 while controlling tracking servo, focusing servo, etc., and data recorded on the optical disc 1 is read out. Do.

  At this time, the optical pickup 16 is operated to be fed in the radial direction of the optical disc 1 by the moving mechanism 21 described above according to the recording position and the reproduction position. For example, when the pickup base 18 to which the optical pickup 16 is attached is moved from the position shown in FIG. 4A to the position shown in FIG. 4B by the moving mechanism 21, the driving force of the drive motor 23 is changed from the first to the third. The pickup base 18 connected to the drive gear 31 and the first rack 24 is guided by the guide shaft 22 by being transmitted to the drive gear 31 via the intermediate gears 26, 27, and 28 and rotating the drive gear 31. Move linearly.

  Before the movement shown in FIG. 4A, the slider 33 of the backlash removal mechanism 32 is slid in the direction of the arrow D in FIG. 4 according to the position of the first rack 24. At this time, the constant force spring 36 in a curved state urges the slider 33 in the direction of arrow P in FIG. 4A with a predetermined load, and the slider 33 interlocked via the connecting gear 35 also urges in the same direction. To do. As a result, a rotational urging force corresponding to the urging direction of the slider 33 is also applied to the gears 26, 27, 28, 29, 31 constituting the reduction gear block 25.

  When moving to the position shown in FIG. 4B, the pickup base 18 is slid in the direction of arrow D in FIG. Then, the slider 33 to which the first rack 24 and the connection gear 35 are attached slides in the same direction according to the rotation amount of the connection gear 35, and the constant force spring 36 is changed according to the slide amount of the slider 33. It will bend, that is, bend more than the state of 4 (A). Even in this case, the constant force spring 36 urges the slider 33 and further the first rack 24 in the direction of arrow P in FIG. 4B with a substantially constant load regardless of the amount of deflection. Accordingly, a rotational biasing force corresponding to the biasing direction of the slider 33 is also applied to each of the gears 26, 27, 28, 29, and 31 constituting the reduction gear block 25, and the backlash in the reduction gear block 25 is removed.

  In the backlash removal mechanism 32, the urging force from the constant force spring 36 is substantially constant over the state of FIG. 4A and the state of FIG. It can be almost the same. Accordingly, the drive motor 23 can be easily controlled. Further, the backlash removal mechanism 32 makes the first rack 24 and the second rack 34 close by making the connecting gear 35 that connects the first rack 24 and the second rack 34 a two-stage gear. Furthermore, by connecting the connecting gear 35 to the second rack 34, the sliding amount of the slider 33 can be reduced, and the mechanism can be miniaturized.

  The present invention can be applied to a stationary disk recording / reproducing apparatus in addition to the above-described in-vehicle disk recording / reproducing apparatus 10.

1 is an exploded perspective view of a disc recording / reproducing apparatus to which the present invention is applied. It is a top view of a backlash removal mechanism. It is a figure which shows the relationship between the deflection amount and load of a constant force spring and a tension coil spring. (A) is a plan view of the backlash removal mechanism before the pickup base is moved, and (B) is a plan view of the backlash removal mechanism after the movement.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical disk, 1a Center hole, 10 Disk recording / reproducing apparatus, 11 Base, 12 Disk rotation drive mechanism, 13 Disk table, 14 Spindle motor, 15 Spindle, 16 Optical pick-up, 16a Objective lens, 17 Opening part, 18 Pickup base, 21 Movement mechanism, 22 guide shaft, 23 drive motor, 24 first rack, 25 reduction gear block, 26 first intermediate gear, 27 second intermediate gear, 28 third intermediate gear, 29 worm, 31 drive gear, 32 Backlash removal mechanism, 33 Slider, 34 Second rack, 35 Connecting gear, 36 Constant force spring, 41 Rotating support member, 44 Disc holding plate

Claims (3)

A first rack mounted with an optical pickup and moving relative to the base;
A drive source for moving the optical pickup;
A gear block connecting the drive source and the first rack by a plurality of gear trains;
A backlash removing mechanism for removing the backlash of the gear block,
The backlash removal mechanism includes a slider that slides relative to the base in the same direction as the first rack;
A second rack provided on the base;
A connecting gear attached to the slider and connecting the first rack and the second rack of the base;
One end is attached to the base, the other end is attached to the slider, and has a load applying member that applies a constant load to the slider,
The connecting gear for connecting the first rack and the second rack is a two-stage gear,
The load applying member is a moving mechanism of the optical pickup which is a constant force spring that is stretched between the base and the slider in a state where the coil spring is always curved. The optical pickup moving mechanism according to claim 1 , wherein one gear portion of the coupling gear is connected to the first rack of the optical pickup , and the other gear portion is connected to the second rack of the base. Base and
A disk rotation drive mechanism provided on the base for rotating the mounted optical disk;
An optical pickup that irradiates a light beam to the optical disk rotated by the disk rotation driving mechanism and detects a return light beam reflected by the optical disk;
A pickup base provided with the optical pickup;
A moving mechanism for moving the pickup base in the radial direction of the optical disk mounted on the disk rotation drive mechanism,
The moving mechanism includes a first rack provided on the pickup base;
A drive source for moving the pickup base;
A gear block connecting the drive source and the first rack by a plurality of gear trains;
A backlash removal mechanism for removing the backlash of the gear block,
The backlash removal mechanism includes a slider that slides relative to the base in the same direction as the first rack;
A second rack provided on the base;
A connecting gear attached to the slider and connecting the first rack and the second rack of the base;
One end is attached to the base, the other end is attached to the slider, and has a load applying member that applies a constant load to the slider,
The connecting gear for connecting the first rack and the second rack is a two-stage gear,
The disk recording and / or reproducing apparatus, wherein the load applying member is a constant force spring that is stretched between the base and the slider in a state where the coil spring is always curved.

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