JP3755243B2 - Optical pickup device and optical disk device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical pickup apparatus and an optical disk apparatus that are suitable for application to a disk reproducing apparatus or the like. Specifically, when one of the two guides supporting the optical pickup body is used as a reference guide, the reference guide is attached in parallel to the radial direction of the disk, and the other guide is attached to the reference guide. By tilting and mounting, the wear of the bearing portion through which the tilt guide is inserted is reduced, so that stable running performance can be obtained.
[0002]
[Prior art]
An optical pickup device 10 as shown in FIG. 7 is often used for recording / reproducing signals (data) to / from an optical disk such as a magneto-optical disk (MO) or a compact disk CD. That is, an optical pickup device 10 that slides toward the radius center 12a of the disk 12 is provided as shown in FIG.
[0003]
This optical pickup device 10 has a substantially rectangular parallelepiped main body 18 as shown. In the main body 18, an optical system for irradiating the disk surface with a light source such as a semiconductor laser or the like and reflecting the laser beam reflected from the disk to the light receiving element, or for imaging the laser on the disk surface. The objective lens 20 and the like are accommodated.
[0004]
In order to allow the optical pickup body 18 to slide toward the center of the disk, a pair of rod-shaped guides 14 and 16 are provided in this example, and one guide, in this example, the lower guide 14 functions as a reference guide, The reference guide 14 is inserted into a pair of round hole bearing portions 22 a and 22 b extending from the optical pickup body 18, and the other guide 16 is inserted into a single round hole bearing portion 24 so that it can advance and retreat with respect to the disk 12. It is comprised so that.
[0005]
As shown in FIG. 8, a magnet 26 is attached to the optical pickup body 18 and is disposed so as to be in a non-contact state with respect to the top surface of the guide 16. A force for pressing the optical pickup body 18 toward the guide 16 is applied by the magnet 26, and stable running is realized without rattling.
[0006]
As a configuration of the bearing portion 24 with respect to the guide 16, a bearing portion having a U-shaped configuration as shown in FIG. 9 can be used.
[0007]
[Problems to be solved by the invention]
By the way, the optical pickup body 18 can realize stable running by the magnet 26 provided in the optical pickup body 18. However, if the pressurization method in which the optical pickup main body 18 is pressed downward as described above is employed, the following problems are caused.
[0008]
The guide 16 is attached and fixed to the apparatus chassis (housing) so as to be parallel to the reference guide 14 with considerable accuracy. On the other hand, the bearing portion 24 is inserted into the guide 16 with a certain clearance as shown in FIG. ing. When the guide 16 is pressurized, the guide 16 and the inner surface 24a of the bearing portion 24 are in point contact at the direct apex P as shown in FIG. Therefore, considering the longitudinal direction of the guide 16, the locus of this point contact is a line contact with a minimum width with respect to the main body slide direction as shown by a straight line LP in FIG.
[0009]
Since the optical pickup body 18 is constantly pressurized by the magnet 26, the direct apex P is worn due to line contact during sliding for a long period of time and slightly wears down, so that an inner surface 24a as shown in FIG. A linear recess 28 is formed by shaving. As a result, the optical pickup main body 18 is inclined slightly, but there is a case where data recording / reproduction cannot be performed satisfactorily. Further, when worn, the contact is changed from line contact to surface contact, and extra friction is generated. This causes a problem that the drive system of the optical pickup main body 18 requires extra power.
[0010]
Therefore, the present invention solves such a conventional problem, and is a light that realizes a stable running state by devising so that the wear of the bearing portion does not proceed even if the optical pickup body 18 is pressurized. A pickup device and an optical disk device are proposed.
[0011]
[Means for Solving the Problems]
In order to solve the above-described problem, in the optical pickup device according to the first aspect of the present invention, one of the two guides supporting the optical pickup body that slides in the radial direction of the disk serves as a reference guide. The other guide is arranged in parallel with the radial direction, and the other guide is a bearing of the optical pickup main body through which the other guide and the other guide are inserted depending on a position where the optical pickup main body slides in the radial direction of the disk. It is characterized by being disposed at a predetermined angle with respect to the reference guide so that the position of contact with the part changes .
[0012]
In the present invention, one of the two guides is arranged as a reference guide in parallel with the disk radial direction. On the other hand, the other guide is attached with a slight inclination with respect to the reference guide. Then, when the optical pickup main body is stopped, a pinpoint contact is made to contact only the direct apex. However, when the optical pickup main body slides, the contact position between the inclined guide and the inner surface of the bearing portion gradually shifts. Therefore, the width of the inner wall surface with which the inclined guide contacts increases. That is, when viewed from the side of the apparatus, the optical pickup main body slides to make surface contact. When the surface contact is made, the contact area is increased accordingly, so that the amount of wear is greatly reduced, and it becomes difficult to form a concave portion associated with wear as in the conventional case. As a result, a stable running state can be realized even after long-term use.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of an optical pickup device according to the present invention will be described in detail with reference to the drawings. The disc as a recording medium is not particularly limited to the type such as an optical disc, a compact disc, and a mini disc. This is because the slide systems of these optical pickup devices are considered to be basically the same.
[0014]
FIG. 1 shows one embodiment when the optical pickup device according to the present invention is applied to a recording / reproducing apparatus for a mini-disc. This figure basically has the same configuration as the conventional optical pickup device 10 shown in FIG. 7, and is provided with an optical pickup device 10 that slides in the radial direction of the mini-disc 12. The optical pickup device 10 has a main body 18 that can be moved back and forth. In the optical pickup main body 18, an optical system that guides a semiconductor laser, which is a light source, or a laser to the surface of the mini disk 12 through the objective lens 20, as in the past. (None of them are shown in the figure).
[0015]
The present invention can also be applied to a semiconductor laser disposed on the apparatus fixing side and only the optical system mounted on the optical pickup body 18.
[0016]
The optical pickup main body 10 advances and retreats to and from the mini-disc 12 using two metal rod-shaped guides 14 and 17 as guides. As a driving means for advancing and retreating, a linear motor method, a rack and pinion method, a lead screw method, etc. Well-known means can be used. Since this driving means is not directly related to the present invention, its configuration and description are omitted.
[0017]
In order to move the optical pickup body 18 forward and backward, the optical pickup body 18 is provided with a pair of bearing portions 22a and 22b through which one guide 14 is inserted, and the guide 17 is inserted through the other guide 17 side. Two bearing portions 23 are provided. For stable running, the optical pickup main body 18 is pressurized toward the guide 17 by a magnet 26 provided on the main body 18.
[0018]
In the present invention, one of the guides in this example, the lower guide 14 functions as a reference guide. The reference guide 14 is attached and fixed to the apparatus chassis (not shown) side in a state of being positioned with high accuracy so as to be parallel to the disk radius center 12a.
[0019]
On the other hand, the other guide 17 is attached in an inclined state with respect to the reference guide 14. In other words, the guides 14 and 17 are normally positioned with high accuracy so as to be parallel, but in the present invention, they are intentionally tilted with respect to the sliding direction. The tilting direction is such that when the two guides are attached in parallel, the center line of the other guide (hereinafter referred to as the tilting guide) 17 is placed on a virtual plane formed by the center lines of the two guides. Tilt to. In the case of FIG. 1, it is attached to the apparatus chassis at a predetermined angle θ.
[0020]
Although the inclination angle θ differs depending on the size of the apparatus (that is, the slide amount), when the guide length is 50 mm and the slide length (slide width) is about 20 to 25 mm, the deviation may be about 0.5 mm. The inclination angle θ is about 0 degree 36 minutes. This value is just an example.
[0021]
Therefore, as shown in FIG. 2, the bearing portion 23 provided in the optical pickup main body 18 has an inner diameter configured as a long hole 23b. When the round hole configuration is adopted, when the optical pickup main body 18 slides on the inclined guide 17, it collides with the inner diameter wall of the bearing portion 23 to prevent smooth travel. The horizontal width (long side) of the long hole 23b is determined by the inclination angle θ and the slide length, and can be selected to an arbitrary length as long as it is longer than the horizontal width determined by these. Moreover, the long hole 23b is made into the short side substantially the same as the diameter of the inclination guide 17 penetrated here.
[0022]
The configuration of the bearing portion 23 is not limited to the long hole configuration described above, but can be configured as a U-shaped portion 23c with a side surface released as shown in FIG. In this case, the lateral width of the U-shaped portion 23c can be made the same as the length of the long side of the long hole 23b in FIG.
[0023]
When the bearing portion 23 on the inclined guide 17 side is configured in this way, the magnet 26 is attached to the optical pickup body 18 for pressurization as shown in FIG. The optical pickup main body 18 is constantly pressed downward while facing a small gap. Therefore, as shown in FIG. 4, the inclined guide 17 slides in a state of being in contact with the top wall 25 of the long hole 23 b.
[0024]
Since the inclined guide 17 is inclined by θ as shown in FIG. 5, the line contact straight line LP indicating the locus of the point contact point of the inclined guide 17 also has an inclination of θ with respect to the reference line LO. Therefore, when the optical pickup main body 18 is at the standby position (when the main body 18 is positioned on the outer diameter side of the disk 12), the inclined guide 17 is positioned on the leftmost side (solid line position) as shown in FIG. In this case, the position of the inclined guide 17 is gradually shifted in the sliding direction, and when it reaches the innermost diameter portion of the disk 12, it is positioned on the rightmost side (chain line position). Therefore, the contact point between the top wall 25 and the inclined guide 17 is also displaced in the sliding direction, and moves within the width W as shown in FIG.
[0025]
As described above, the contact point between the top wall 25 and the inclined guide 17 moves depending on the slide position, so that the contact range of the top wall 25 with which the inclined guide 17 contacts is increased. That is, when the optical pickup body 18 slides, the contact line between the top wall 25 and the inclined guide 17 is moved, and the contact range becomes a surface. Therefore, since the contact area of the top wall 25 increases accordingly, the amount of wear is greatly reduced, and it becomes difficult to form the recesses 28 associated with the conventional wear. As a result, a stable running state can be realized even after long-term use. That is, even if the optical pickup device 10 is used for a long time, a situation in which a part of the inner diameter of the bearing portion 23 is deformed due to wear does not occur.
[0026]
Therefore, it is possible to realize stable running at all times, and to achieve a long life of the optical pickup device 10. Further, unlike the prior art, there is no possibility that the optical pickup body 18 is slightly inclined with respect to the disk surface due to the wear of the bearing portion 23, and this causes the recording / reproduction characteristics to the disk 12 to deteriorate.
[0027]
【The invention's effect】
As described above, according to the present invention, one of the two guides is inclined with respect to the other guide.
[0028]
As a result, the contact point between the tilted guide and the bearing portion moves along the sliding direction and moves in a surface contact manner. Therefore, even if the optical pickup device is used for a long time, the inner diameter of the bearing portion remains constant. The part is not deformed by wear. Therefore, it is possible to realize stable running at all times and to extend the life of the optical pickup device.
[0029]
Of course, there is no possibility that the optical pickup main body is slightly tilted with respect to the disk surface due to wear of the bearing portion, thereby deteriorating the recording / reproducing characteristics on the disk.
[0030]
Therefore, the present invention is extremely suitable when applied to a reproducing apparatus or a recording / reproducing apparatus using a disc-shaped recording medium such as an optical disc, a mini disc, or a compact disc.
[Brief description of the drawings]
FIG. 1 is a configuration diagram (plan view) of a main part showing an embodiment of an optical pickup device according to the present invention.
FIG. 2 is a side view thereof.
FIG. 3 is a side view similar to FIG. 2 in which a bearing portion is changed.
FIG. 4 is an enlarged view of a bearing portion.
FIG. 5 is a diagram showing a contact locus of an inclined guide.
FIG. 6 is a partially enlarged side view thereof.
FIG. 7 is a plan view of a main part showing an embodiment of a conventional optical pickup device.
FIG. 8 is a side view thereof.
FIG. 9 is a side view similar to FIG. 8 with the bearing part changed.
FIG. 10 is an enlarged view of a bearing portion.
FIG. 11 is a diagram showing a contact locus of an inclined guide.
FIG. 12 is a partially enlarged side view thereof.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Optical pick-up apparatus 12 Disc 14 Reference | standard guide 17 Inclination guide 22a, 22b, 23, 24 Bearing part 24b Long hole 24c U-shaped part 25 Top wall

Claims (4)

Of the two guides that support the optical pickup body that slides in the radial direction of the disk, one guide is arranged in parallel with the radial direction as a reference guide,
The other guide is configured such that the contact position between the other guide and the bearing portion of the optical pickup body through which the other guide is inserted changes depending on the position at which the optical pickup body slides in the radial direction of the disk. An optical pickup device disposed at a predetermined angle with respect to the reference guide . 2. The optical pickup device according to claim 1 , wherein a shape of the bearing portion of the optical pickup body is formed in a long hole or a U-shape . 2. The optical pickup device according to claim 1, wherein a magnet that absorbs shakiness of the bearing portion with respect to the other guide is provided in the optical pickup body . Of the two guides that support the optical pickup body that slides in the radial direction of the disk, one guide is arranged as a reference guide in parallel with the radial direction,
  The other guide is configured such that the contact position between the other guide and the bearing portion of the optical pickup body through which the other guide is inserted changes depending on the position at which the optical pickup body slides in the radial direction of the disk. And an optical pickup device disposed at a predetermined angle with respect to the reference guide.
An optical disc device characterized by the above.

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