JP2009004015A - Optical pickup feeding device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform normal operations smoothly by uniforming an initial load in any of optical pickup feeding directions. <P>SOLUTION: The optical pickup feeding device includes: a lead screw disposed so as to extend along the moving direction of the optical pickup at the one-side of the optical pickup and including a spiral groove on a circumferential surface; a motor rotating the lead screw; and a rack disposed at the one-side of the optical pickup and engaged with the spiral groove. The rack includes: an attachment part attached to the one-side of the optical pickup; an engagement part engaged with the spiral groove; a support part formed integrally with the attachment part and supporting the engagement part so that a fulcrum of a force applied to the engagement part by the lead screw is disposed on a line extending from the engagement point of the lead screw and the engagement part to the tangential direction of the lead screw; and an energization part applying a force to the engagement part along a direction perpendicular to the tangential direction so that the engagement part is pressed against the lead screw. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optical pickup feeding device.

  In general, the optical disk drive is equipped with an optical pickup feeding device that moves the optical pickup in the radial direction of the optical disk. In the conventional optical pickup feeder, the optical pickup is moved by engaging the teeth of the rack attached to the optical pickup with the groove of the lead screw and rotating the lead screw by a motor (for example, Patent Document 1). reference).

  More specifically, as shown in FIG. 4, the optical pickup feeder 100 has a base 101, a spindle motor 102 disposed on the base 101, and an optical disk (not shown) mounted on the motor shaft of the spindle motor 102. A turntable 103 that rotates as a unit while being placed is provided.

  Also, on the base 101, an optical pickup 104 for recording and / or reproducing with respect to the optical disc, a pair of guide shafts 105, 106 for guiding the optical pickup 104 in the radial direction of the optical disc, and guide shafts 105, 106 Are provided with a lead screw 107 for feeding the optical pickup 104 supported by the radial direction in the radial direction, and a motor M for rotating the lead screw 107.

  A rack 108 that engages with the lead screw 107 is mounted on one end of the optical pickup 104 on the lead screw 107 side. FIG. 5 is a perspective view showing an engaged state of the lead screw 107 and the rack 108, and FIG. 6 is a side view. As shown in FIGS. 5 and 6, the rack 108 includes an attachment portion 110 attached to the optical pickup 104, an inclined portion 111 that is inclined downward from the tip of the attachment portion 110, and an inclined portion 111. An extension part 112 extending upward from the tip end and a meshing part 114 held by the extension part 112 and meshing with the spiral groove 113 of the lead screw 107 are provided. Is formed.

Further, a compression spring 115 for biasing a predetermined force to the meshing portion 114 via the extension portion 112 is interposed between the attachment portion 110 and the extension portion 112. Here, when the optical pickup 104 is sent at a high speed, it is necessary to increase the rotational speed of the motor M. In this case, the meshing portion 114 of the rack 108 is disengaged from the spiral groove 113 of the lead screw 107, so-called tooth skipping. It is easy to cause. In order to prevent this, the meshing portion 114 of the rack 108 is pressed against the lead screw 107 by the biasing force of the compression spring 115 described above.
JP 2006-266469 A

  By the way, in the optical pickup feeding device 100 described above, a moment based on the rotation of the lead screw 107 acts on the connecting portion (fulcrum P1) between the extending portion 112 and the inclined portion 111, but at the position described above. The presence of the fulcrum P1 causes a difference in moment depending on the direction of rotation of the lead screw 107. For example, when the lead screw 107 rotates counterclockwise (arrow Y1 in FIG. 6), the portion where the spiral groove 113 of the lead screw 107 and the meshing portion 114 of the rack 108 come into contact (operation point P2). The force F1 is transmitted toward the upper left of the figure, and a moment M1 is applied to the fulcrum P1. On the other hand, when the lead screw 107 rotates counterclockwise (arrow Y2 in FIG. 6), a force F2 is transmitted to the action point P2 toward the lower left of the figure, and thereby a moment M2 is applied to the fulcrum P1. Since the magnitudes of the moments M1 and M2 are different, if the rotation direction of the lead screw 107, that is, the feeding direction of the optical pickup 104 is different, the deflection amount of the rack 108 is also different.

  Here, the urging force by the compression spring 115 described above needs to be set to a force that does not cause tooth skipping, but the forces F1 and F2 applied to the rack 108 and the moments M1 and M2 differ depending on the feed direction. And you have to set the biasing force according to the big value. For this reason, an extra urging force is applied from the direction in which tooth skipping is unlikely to occur (the direction in which the force and moment are small values). This extra urging force acts as an extra initial load on the operation of the optical pickup 104, and may hinder normal operation.

  An object of the present invention is to make the initial load uniform and smooth the normal operation even in any of the feeding directions of the optical pickup.

An optical pickup feeding device according to the invention described in claim 1 is:
A lead screw disposed on one side of the optical pickup so as to extend along the moving direction of the optical pickup, and having a spiral groove on the peripheral surface;
A motor for rotating the lead screw;
A rack disposed on one side of the optical pickup and engaged with a spiral groove of the lead screw;
The rack is
An attachment portion attached to one side of the optical pickup;
A meshing portion meshing with the spiral groove of the lead screw;
The fulcrum of force that is formed integrally with the mounting portion and applied to the meshing portion by the lead screw is arranged on a line extending in the tangential direction of the lead screw from the meshing point of the lead screw and the meshing portion. And a support part for supporting the meshing part,
And a biasing portion that biases a force along a direction perpendicular to the tangential direction with respect to the meshing portion so as to press the meshing portion against the lead screw.

The invention according to claim 2
In the pickup feeding device according to claim 1,
The extending portion is characterized in that the meshing portion is rotatably supported.

  According to the present invention, the meshing portion is supported so that the fulcrum of the force applied to the meshing portion by the lead screw is arranged on a line extending in the tangential direction of the lead screw from the meshing point of the lead screw and the meshing portion. Therefore, even if the rotation direction of the lead screw is different, the force due to the rotation acts uniformly on the fulcrum. As a result, it is possible to suppress an excessive application of the urging force by the urging unit, and it is possible to make the initial load uniform and smooth the normal operation.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side view showing a schematic configuration of an optical pickup feeding apparatus according to the present embodiment. As shown in FIG. 1, the optical pickup feeding device 1 is arranged on one side of the optical pickup 2 so as to extend along the moving direction of the optical pickup 2, and has a spiral groove 3 on the peripheral surface. The lead screw 4 has a motor 5 that rotates the lead screw 4, and a rack 6 that is disposed on one side of the optical pickup 2 and engages with the spiral groove 3 of the lead screw 4.

  The rack 6 is integrally formed with an attachment portion 61 that is attached to one side portion of the optical pickup 2 on the lead screw 4 side, a meshing portion 62 that meshes with the spiral groove 3 of the lead screw 4, and the attachment portion 61. A support portion 63 that supports the meshing portion 62 and a biasing portion 64 that presses the meshing portion 62 against the lead screw 4 are provided.

The support portion 63 is a line in which the fulcrum of the force applied to the engagement portion 62 by the lead screw 4 extends from the engagement point S1 of the lead screw 4 and the engagement portion 62 in the tangential direction of the lead screw 4 (vertical direction in the present embodiment). The meshing portion 62 is supported so as to be disposed on S2.
Specifically, the support portion 63 includes an inclined portion 65 that is inclined so as to be lowered from the attachment portion 61, and an extended portion 66 that extends upward from the tip of the inclined portion 65 and supports the meshing portion 62. And are provided. The inclined portion 65 and the extending portion 66 are integrally formed, and the connecting portion is disposed on the line S2. And the notch 67 is formed in the connection part, The force added to the meshing part 62 by rotation of the lead screw 4 concentrates. That is, this connecting portion becomes a fulcrum P3 of the force applied to the meshing portion 62.

  The urging portion 64 is, for example, a compression spring, and is disposed between the attachment portion 61 and the engagement portion 62 so as to press the engagement portion 62 against the lead screw 4. Since the urging portion 64 is arranged such that the expansion / contraction direction is along the direction orthogonal to the line S2, the force along the orthogonal direction is urged to the meshing portion 62.

Next, the operation of this embodiment will be described.
First, when the lead screw 4 is rotated counterclockwise by the motor 5 (arrow Y3), the force F3 is transmitted to the meshing point S1 of the lead screw 4 and the meshing portion 62 toward the upper right in the figure, and therefore, the moment P3 M3 (see FIG. 2: M3 = (component force F4 in the horizontal direction of F3) × (interval L between the meshing point S1 and the fulcrum P3)) is applied. Then, a force F4 is applied to the meshing portion 62 in the direction opposite to the urging force by the urging portion 64 (direction to press against the optical pickup 2).

  On the other hand, when the lead screw 4 is rotated clockwise by the motor 5 (arrow Y4), a force F5 is transmitted to the meshing point S1 toward the lower right in the figure, and therefore, the moment M4 (see FIG. 2: M4 = (Horizontal component force F6 of F5) × (interval L between the meshing point S1 and the fulcrum P3) is applied. Since the fulcrum P3 is arranged on the line S2 extending in the tangential direction of the lead screw 4 from the meshing point S1, the magnitude of the force F5 and the angle (angle α) with respect to the horizontal plane H are counterclockwise. This is the same as the magnitude of the force F3 when rotated and the angle β with respect to the horizontal plane H. That is, the moment M4 is the same as the moment M3. A force is applied to the meshing portion 62 in the direction opposite to the urging force by the urging portion 64.

  As described above, according to the present embodiment, the fulcrum P3 of the force applied to the meshing portion 62 by the lead screw 4 is arranged on the line S2 extending from the meshing point S1 in the tangential direction of the lead screw 4. Since the meshing part 62 is supported, even if the rotation direction of the lead screw 4 is different, the force due to the rotation acts uniformly on the fulcrum S1. As a result, it is possible to suppress an excessive application of the urging force by the urging unit 64, and it is possible to make the initial load uniform and smooth the normal operation.

Of course, the present invention is not limited to the above-described embodiment and can be modified as appropriate.
For example, in the above-described embodiment, the configuration in which the extension portion 66 and the meshing portion 62 are fixed is illustrated. However, in order to set the biasing force of the biasing portion 64 smaller, the extension portion 66 and the meshing portion 62 May be supported rotatably.

An embodiment in this case will be described with reference to FIG.
FIG. 3 is based on the embodiment of FIG. 1 and mainly describes different parts. The spiral groove 3, the lead screw 4, the inclined portion 65, the notch 67, and the urging portion 64 have the same configuration. As a difference, the engaging portion 62 is rotatably supported by the shaft 70 with respect to the extending portion 66.

  In FIG. 3, the meshing portion 62 that is rotatably arranged is inclined clockwise around the shaft 70, and this shows a state in which the motor that rotates the lead screw 4 is rotated counterclockwise. . When the rotation direction of the motor is clockwise, the meshing portion 62 is tilted counterclockwise around the shaft 70.

  In such a case, it is possible to prevent the meshing portion 62 from being detached from the spiral groove 3 by rotating the meshing portion 62 corresponding to the rotation direction of the lead screw 4. Therefore, the urging force of the urging unit 64 can be further reduced, and the initial load can be reduced.

It is a side view which shows schematic structure of the optical pick-up feeder which concerns on this embodiment. It is explanatory drawing which shows the force added by the difference in the rotation direction of the lead screw with which the optical pick-up feeder of FIG. 1 is equipped. It is a side view which shows the modification of the optical pick-up feeder of FIG. It is a perspective view which shows schematic structure of the conventional optical pick-up feeder. It is a perspective view which shows the engagement state of the lead screw and rack of the optical pick-up feeder of FIG. It is a side view which shows the engagement state of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical pick-up feeder 2 Optical pick-up 3 Helical groove 4 Lead screw 5 Motor 6 Rack 61 Mounting part 62 Engagement part 63 Support part 64 Energizing part 65 Inclination part 66 Extension part 67 Notch

Claims (2)

A lead screw disposed on one side of the optical pickup so as to extend along the moving direction of the optical pickup, and having a spiral groove on the peripheral surface;
A motor for rotating the lead screw;
A rack disposed on one side of the optical pickup and engaged with a spiral groove of the lead screw;
The rack is
An attachment portion attached to one side of the optical pickup;
A meshing portion meshing with the spiral groove of the lead screw;
The fulcrum of force that is formed integrally with the mounting portion and applied to the meshing portion by the lead screw is arranged on a line extending in the tangential direction of the lead screw from the meshing point of the lead screw and the meshing portion. And a support part for supporting the meshing part,
An optical pickup feeding device comprising: an urging portion that urges a force along a direction perpendicular to the tangential direction with respect to the engagement portion so as to press the engagement portion against the lead screw. In the pickup feeding device according to claim 1,
The optical pickup feeding device, wherein the extension part rotatably supports the meshing part.