JP4982441B2 - Optical pickup device - Google Patents

Description

  The present invention relates to an optical pickup apparatus for recording / reproducing information on / from an optical recording medium, and more particularly to an optical pickup apparatus formed with a mold optical component mounting direction as a processing direction.

  FIG. 11 is a diagram showing an optical disk drive device 80 according to the prior art. The optical disk drive 80 records or reproduces information signals on a base chassis 81 constituting the main body, a disk drive unit 83 that rotationally drives the optical disk 82, and an optical disk 82 that is mounted on the disk drive unit 83. The optical pickup 84 includes a first guide shaft 85 and a second guide shaft 86 that support the optical pickup 84 movably along the radial direction of the optical disk 82.

The optical disc 82 is, for example, a CD (Compact Disc) or a DVD (Digital Versatile).
Disc). The turntable on which the optical disk 82 is mounted is attached to the rotating shaft of the spindle motor and is driven by the spindle motor. The laser beam emitted from the optical pickup 84 is applied to the signal recording surface of the optical disk 82.

  FIG. 12 is an external view of the optical pickup 84. FIG. 12A is a plan view of the optical pickup 84. FIG. 12B is a side view of the optical pickup 84 viewed from the right. FIG. 12C is a bottom view of the optical pickup 84. FIG. 12D is a cross-sectional view taken along a cutting plane line HH including the central axis of the bearing component 91.

  The optical pickup 84 includes a pickup base 87, an objective lens 88 that is disposed on the upper surface side of the pickup base 87 and focuses the light beam on the signal recording surface of the optical disk 82, a light source that emits the light beam, and the optical disk 82. The optical pickup device includes a light receiving element that detects a returning light beam reflected from the signal recording surface, and a drive system that drives the objective lens 88 in the focusing direction and tracking direction of the optical disk 82. The optical pickup 84 writes or reads a signal on the signal recording surface of the optical disk 82.

  FIG. 13 is an external view of the pickup base 87. FIG. 13A is a plan view of the pickup base 87. FIG. 13B is a side view of the pickup base 87 viewed from the right. FIG. 13C is a bottom view of the pickup base 87. A holding portion 89 in which a through hole 90 is formed is provided at one end of both ends of the pickup base 87 in a direction orthogonal to the moving direction of the pickup base 87. The central axis of the through hole 90 coincides with the moving direction of the pickup base 87. A bearing component 91 is fitted into the through hole 90. The first guide shaft 85 is inserted through the bearing component 91. The first guide shaft 85 supports the optical pickup 84 so as to be movable in the moving direction of the pickup base 87.

  A holding portion 92 is formed at the other end of the pickup base 87. The holding portion 92 includes holding pieces 93 that are formed at two locations at intervals in the same direction as the central axis of the first guide shaft 85. The holding piece 93 sandwiches the second guide shaft 86 in the direction of the rotation axis of the optical disk 82.

  Patent Document 1 discloses an information recording / reproducing apparatus that can keep sliding resistance small even when dust such as cotton dust or sand dust adheres to the surfaces of a main shaft and a driven shaft that movably support a carriage. The carriage includes an information recording / reproducing unit and a main bearing and a driven bearing through which the main shaft and the driven shaft are inserted. The main bearing is provided with four convex portions at equal intervals on the circumference of the inner peripheral portion, and the convex portions slide on the main shaft. In the driven bearing, convex portions are provided at two equal intervals on the circumference of the inner peripheral portion, and the convex portions move on the driven shaft. Only the convex part contacts the surface of the main shaft or the driven shaft.

JP 10-312652 A

  The angle formed by the direction X of the central axis of the through-hole 90 formed at one end of the both ends of the direction Y orthogonal to the moving direction of the pickup base 87 and the direction Z in which the pickup optical component is mounted is , 90 °. The mold for processing the pickup base 87 is processed with the optical component mounting direction Z as the processing direction. In order to process the through-hole 90, it is necessary to have a slide structure that can process in a direction orthogonal to the optical component mounting direction Z.

  However, when the slide structure is provided, the structure of the mold becomes complicated and the time required for processing becomes long. The number of pickup bases 87 that can be processed per unit time is limited, leading to an increase in cost. Patent Document 1 discloses reducing the sliding resistance of the main shaft and the driven shaft that support the carriage, but does not disclose forming the bearing portion by machining the mold in the vertical direction.

  An object of the present invention is to provide an optical pickup device using a pickup base that is formed with only the optical component mounting direction of a mold as a processing direction.

The present invention includes an objective lens that focuses laser light on a signal recording surface of an optical recording medium, an objective lens moving unit that moves the objective lens, and a pickup base that mounts the objective lens and the objective lens moving unit. An optical pickup device comprising:
The pickup base includes at least one guide shaft holding portion through which a guide shaft for moving the pickup base in the radial direction of the optical recording medium is inserted,
The guide shaft holding portion has at least three holding portions each having an arcuate recess having a central angle of 180 ° or less with respect to the same central axis as the guide shaft so that the guide shaft is sandwiched between the recesses. An optical pickup device having the same shape as that of the optical pickup.

  According to the present invention, the objective lens for condensing the laser beam on the signal recording surface of the optical recording medium, the objective lens moving unit for moving the objective lens, and the pickup base on which the objective lens and the objective lens moving unit are mounted are provided. The pickup base includes at least one guide shaft holding portion through which a guide shaft for moving the pickup base in the radial direction of the optical recording medium is inserted. The guide shaft holding portion is based on the same central axis as the guide shaft. The at least three holding portions having arcuate concave portions with a central angle of 180 ° or less are the same shape as the shape in which the guide shafts are sandwiched between the concave portions. Therefore, the optical component mounting direction of the mold can be formed as the processing direction.

FIG. 1 is a diagram showing an optical pickup device 1 according to a first embodiment of the present invention. FIG. 1A is a plan view of the optical pickup device 1. FIG.1 (b) is the side view which looked at the bearing component holding | maintenance part 10 from the right. FIG. 1C is a bottom view of the optical pickup device 1.
The optical pickup device 1 is mounted on the pickup base 2, the pickup base 2, an objective lens 4 that focuses the light beam on the signal recording surface of the optical disk 3, a light source (not shown) that emits the light beam, and the optical disk 3. The optical pickup device includes a light receiving element (not shown) that detects a returning light beam reflected from the signal recording surface, and a drive system that drives the objective lens 4 in the focusing direction and the tracking direction of the optical disk 3. The focusing direction is a direction for condensing the light spot, and the tracking direction is a direction for tracking the light spot on the information track.

  Two bearing component holding portions 10 are formed at one end of both ends of the pickup base 2 in a direction orthogonal to the moving direction of the pickup base 2. A bearing component 14 is fitted in each of the bearing component holding portions 10. The guide shaft 15 is inserted through the two bearing parts 14. The direction of the central axis of the bearing component 14 matches the moving direction of the pickup base 87.

  FIG. 2 is a diagram showing the bearing component holding unit 10 used in the optical pickup device 1 according to the first embodiment of the present invention. FIG. 2A is a plan view of the bearing component holding unit 10. FIG. 2B is a side view of the bearing component holding portion 10 as viewed from the right. FIG. 2C is a cross-sectional view of the bearing component holding portion 10 cut along a cutting plane line AA in a direction perpendicular to the central axis of the bearing component 14. FIG. 2D is a view showing a cross section of the bearing component holding portion 10 taken along a cutting plane line BB in a direction perpendicular to the central axis of the bearing component 14. FIG. 2E is a bottom view of the bearing component holding unit 10. FIG. 2 (f) is a cross-sectional view of the bearing component holding part 10 taken along the cutting plane line CC of the central axis of the bearing component 14.

  The bearing part holding part 10 which is a guide shaft holding part is formed into a shape in which three holding parts 11 are arranged adjacent to each other. The holding part 11 has a semicircular arc-shaped recess 12 with a central angle of 180 °, and both ends of the recess 12 are provided with straight parts 13 rising in the tangential direction. The two adjacent holding parts 11 are shaped so as to be opposite to each other, and the straight part 13 is arranged in parallel with the rotation axis direction of the optical disc 3. The central axis of the arc of the three holding parts 11 formed adjacent to each other coincides with the central axis of the bearing part 14 fitted to the bearing part holding part 10. The arc of the recess 12 is not limited to 180 °, and may be 180 ° or less.

  The bearing component holding part 10 supports the outer surface of the bearing component 14 at three locations. Of the semicircular arc-shaped concave portion 12 formed by the holding portion 11, two concave portions 12 whose openings are directed to the information reading surface side of the optical disk 3 are both end portions of the outer surface of the bearing component 14 in the central axis direction. Support. One recess 12 whose opening is directed in the direction opposite to the information reading surface of the optical disk 3 supports the central portion of the outer surface of the bearing component 14.

  Since the straight portion 13 of the holding portion 11 is parallel to the rotation axis direction of the optical disk 3 that is the mounting direction of the optical component of the mold, the bearing component holding portion 10 is formed by processing only in the mounting direction of the optical component of the mold. be able to.

  FIG. 3 is a diagram showing a bearing component holding unit 20 used in the optical pickup device 1A according to the second embodiment of the present invention. The configuration of the optical pickup device 1A is the same as that of the optical pickup device 1 shown in FIG. 1 except for the bearing part holding portion 20, and the description of the overlapping portions is omitted. FIG. 3A is a plan view of the bearing component holding unit 20. FIG. 3B is a side view of the bearing component holding portion 20 as viewed from the right. FIG. 3C is a cross-sectional view of the bearing component holding portion 20 cut along a cutting plane line DD in a direction perpendicular to the central axis of the bearing component 14. FIG. 3D is a bottom view of the bearing component holding unit 20.

  The holding portion 21 having the semicircular arc-shaped concave portion 22 having a central angle of 180 ° has a projection 23 formed on the semicircular arc-shaped concave portion 22. Since each of the semicircular arc-shaped recesses 22 is formed with one protrusion 23, the bearing component holding part 20 has three protrusions 23. The three protrusions 23 are arranged at intervals of 120 ° with respect to the central axis of the bearing component 14. The bearing component 14 is held by being pressed against the top of the protrusion 23. Since the bearing component 14 is held by the protrusion 23, when the inclination of the bearing component 14 and the deviation between the center axis of the guide shaft 15 and the center axis of the bearing component 14 are corrected, the range to be corrected is the protrusion 23. Since it is limited, correction becomes easy.

  FIG. 4 is a diagram showing a bearing component holding portion 26 used in the optical pickup device 1B according to the third embodiment of the present invention. The configuration of the optical pickup device 1B is the same as that of the optical pickup device 1 shown in FIG. 1 except for the bearing part holding portion 26, and the description of the overlapping portions is omitted. Tapered ribs 28 that are bearing member removal preventing portions are formed at both axial ends of the inner peripheral surface of the semicircular arc-shaped recess 27 formed in the bearing component holding portion 26. The shape of the taper rib 28 is formed such that the end surface of the recess 27 rises in the direction of the central axis of the bearing component 14 and the top of the taper rib 28 has an acute angle. The taper rib 28 prevents the bearing component 14 fitted to the bearing component holding portion 26 from coming out of the bearing component holding portion 26. When the radius of the semicircular opening at the end of the bearing part holding portion 26 is reduced by forming the tapered rib 28, the bearing part 14 is hardly fitted. Therefore, the height of the taper rib 28 needs to be suppressed to a height at which the bearing component 14 can be press-fitted.

  FIG. 5 is a diagram showing a bearing component holding unit 30 used in the optical pickup device 1C according to the fourth embodiment of the present invention. The configuration of the optical pickup device 1C is the same as that of the optical pickup device 1 shown in FIG. 1 except for the bearing part holding portion 30, and the description of the overlapping portions is omitted. FIG. 5A is a plan view of the bearing component holding unit 30. FIG. 5B is a view showing a cross section of the bearing component holding portion 30 cut along a cutting plane line EE in a direction perpendicular to the central axis of the bearing component 14. The bearing component holding part 30 includes a grease holding rib 33 that is a lubricant holding part.

  The grease holding rib 33 is formed in the opening of the end of the bearing part holding part 30 opposite to the side where the bearing part 14 is inserted. The grease holding rib 33 prevents the grease accumulated between the bearing component 14 from leaking. As shown in FIG. 5B, the height of the grease holding rib 33 needs to be set so as not to contact the guide shaft 15 inserted through the bearing component 14. By forming the grease holding rib 33, excess grease is stored between the grease holding rib 33 and the bearing component 14.

  FIG. 6 is a diagram showing a bearing component holding portion 38 used in the optical pickup device 1D according to the fifth embodiment of the present invention. The configuration of the optical pickup device 1D is the same as that of the optical pickup device 1 shown in FIG. 1 except for the bearing part holding portion 38, and the description of the overlapping portions is omitted. FIG. 6A is a plan view of the bearing component holding portion 38. FIG. 6B is a side view of the bearing component holding portion 38 as viewed from the right. FIG. 6C is a bottom view of the bearing component holding portion 38. When viewed from the arcuate recess 39 into which the bearing component 14 of the bearing component holding portion 38 is fitted, the end 42 on the side opposite to the main body of the pickup base 40 is opened. The concave portions 39 of the holding portions 41 are separated from each other because the central angle is 180 ° or less and the end portions 42 of the holding portions 41 arranged adjacent to each other do not have a joint portion. Each holding part 41 forming the bearing part holding part 38 holds the bearing part 14 by sandwiching the bearing parts 14 alternately. By changing the shape of each holding portion 41, the holding pressure for holding the bearing component 14 can be adjusted.

  FIG. 7 is a diagram showing a bearing component holding unit 50 used in an optical pickup device 1E according to the sixth embodiment of the present invention. The configuration of the optical pickup device 1E is the same as that of the optical pickup device 1 shown in FIG. 1 except for the bearing part holding portion 50, and the description of the overlapping portions is omitted. FIG. 7A is a plan view of the bearing component holding unit 50. FIG.7 (b) is the side view which looked at the bearing component holding | maintenance part 50 from the right. FIG. 7C is a bottom view of the bearing component holding unit 50. The bearing part holding part 50 is separated vertically in the direction of the rotation axis of the optical disk 3. A U-shaped bearing part holding part 51 arranged on the side close to the optical disk 3 sandwiches each bearing part 14 from the side close to the optical disk 3. The bearing component receiving portions 52 disposed on the side far from the optical disk 3 are formed at two locations integrally with the pickup base 53 and sandwich the bearing components 14 from the side far from the optical disk 3.

  The bearing component holding component 51 is molded as a separate component different from the pickup base 53 and is screwed to the pickup base 53. By using a component molded independently as the configuration of the bearing component holding portion 50, the structure of the bearing component receiving portion 52 molded integrally with the pickup base 53 is simplified. Therefore, the bearing component receiving portion 52 can be formed integrally with the pickup base 53 more easily with the optical component mounting direction as the processing direction.

  FIG. 8 is a diagram showing a bearing component holding portion 60 used in the optical pickup device 1F according to the seventh embodiment of the present invention. The configuration of the optical pickup device 1F is the same as that of the optical pickup device 1 shown in FIG. 1 except for the bearing part holding portion 60, and the description of the overlapping portions is omitted. In the optical pickup device 7, ribs 62 that are bearing member removal preventing portions are formed on the optical pickup device 6 shown in FIG. 7. The ribs 62 are formed at both ends in the axial direction of the inner peripheral surface of the semicircular arc-shaped recess of the bearing component receiving portion 61. The shape of the rib 62 is formed by an end surface obtained by raising the end surface of the bearing component receiving portion 61 in the central axis direction of the bearing component 14 and a surface formed on the inner side of the bearing component receiving portion 61 parallel to the end surface. . The bearing component 14 is disposed from the optical disc 3 side in the direction of the rotation axis of the optical disc 3. By providing the rib 62, the bearing component 14 can be prevented from coming off from the bearing component receiving portion 61.

  FIG. 9 is a diagram showing a bearing component holding portion 65 used in the optical pickup device 1G according to the eighth embodiment of the present invention. The configuration of the optical pickup device 1G is the same as that of the optical pickup device 1 shown in FIG. 1 except for the bearing part holding portion 65, and the description of the overlapping portions is omitted. FIG. 9A is a plan view of the bearing component holding portion 65. FIG. 9B is a side view of the bearing component holding portion 65 as viewed from the right. FIG. 9C is a bottom view of the bearing component holding portion 65. FIG. 9D is a view showing a cross section of the bearing component holding portion 65 cut along a cutting plane line FF including the central axis of the guide shaft 15.

  The bearing component holding part 65 includes holding parts 66 formed at three equal intervals. The shape of the holding portion 66 is the same as the shape of the holding portion 11 shown in FIG. Among the holding portions 66, the holding portions 66 arranged at two positions on the outer side are such that the opening of the semicircular arc-shaped concave portion faces the optical disk 3 side, and the side farthest from the optical disk 3 among the side surfaces of the guide shaft 15. To support. Among the holding portions 66, the holding portion 66 arranged at the center portion has a semicircular arc-shaped concave portion whose opening is directed in the direction opposite to the optical disc side, and is on the optical disc 3 on the outer peripheral surface of the guide shaft 15. Support the near side. The guide shaft 15 is held so as to be sandwiched by holding portions 66 formed at three locations.

  FIG. 10 is a diagram showing a bearing component holding portion 70 used in the optical pickup device 1H according to the ninth embodiment of the present invention. The configuration of the optical pickup device 1H is the same as that of the optical pickup device 1 shown in FIG. 1 except for the bearing part holding portion 70, and the description of the overlapping portions is omitted. FIG. 10A is a plan view of the bearing component holder 70. FIG. 10B is a side view of the bearing component holding portion 70 as viewed from the right. FIG. 10C is a bottom view of the bearing component holding unit 70. FIG. 10 (d) is a view showing a cross section of the bearing component holding portion 70 cut along a cutting plane line GG including the central axis of the guide shaft 15. The shape of the bearing part holding part 70 is the same as that of the bearing part holding part 65, but among the holding parts 71 arranged at three locations constituting the bearing part holding part 70, the holding parts 71 arranged at both ends are arranged. The grease holding groove 72 is provided. The grease holding groove 72 is formed as a groove having a certain depth on the surface of the semicircular arc-shaped recess 74 that supports the guide shaft 15. By providing the grease holding groove 72, excess grease is stored in the grease holding groove 72.

  As described above, the objective lens 4 for condensing the laser beam on the signal recording surface of the optical disk 3, the objective lens moving unit for moving the objective lens 4, and the pickup base 2 on which the objective lens 4 and the objective lens moving unit are mounted. The pickup base 2 includes at least one bearing component holding portion 10 through which a guide shaft 15 for moving the pickup base 2 in the radial direction of the optical disk 3 is inserted. The bearing component holding portion 10 includes the guide shaft 15. The at least three holding portions 11 having an arc portion whose center angle is 180 ° or less with respect to the same central axis as the reference shape is the same shape as the shape in which the guide shaft 15 is sandwiched between the arc portions. . Therefore, the pickup base 2 can be molded with the optical component mounting direction of the mold as the processing direction.

  Further, the same shape is a shape in which at least three holding portions 11 are arranged adjacent to each other in the central axis direction of the guide shaft 15, and the guide shaft 15 is a bearing component that is fitted to the bearing component holding portion 10. 14, the bearing component holding portion 10 can be formed by processing in the mold optical component mounting direction.

  Further, the arc portion of the holding portion 11 includes a protrusion whose top portion is in contact with the guide shaft 15 or the bearing component 14. Therefore, the inclination of the bearing component 14 and the deviation between the central axis of the guide shaft 15 and the central axis of the bearing component 14. Since the range to be corrected is limited to the protrusion 23, the correction is facilitated.

  Furthermore, since the bearing component holding part 26 includes the taper rib 28, the bearing part 14 fitted to the bearing part holding part 26 can be prevented from coming off from the bearing part holding part 26.

  Furthermore, since the bearing component holding part 30 includes a grease holding part 32 for preventing the lubricant applied to the bearing part 14 from leaking, excess grease is interposed between the grease holding rib 33 and the bearing part 14. Can be stored.

  Further, the ends of the at least three holding portions 41 are separated on a plane that includes the central axis of the guide shaft 15 and is substantially parallel to the radial direction of the optical disk 3, so that the shape of each holding portion 41 is changed. Thus, the holding pressure for holding the bearing component 14 can be adjusted.

  Further, since the bearing component holding part 50 is composed of a part molded integrally with the pickup base 53 and a part molded separately from the pickup base 53 and detachable from the pickup base 53, the bearing part receiving part 52 is formed. Can be more easily formed integrally with the pickup base 53 with the optical component mounting direction as the processing direction.

1 is a diagram showing an optical pickup device 1 according to a first embodiment of the present invention. It is a figure which shows the bearing component holding | maintenance part 10 used with the optical pick-up apparatus 1 which is the 1st Embodiment of this invention. It is a figure which shows the bearing component holding part 20 used with 1 A of optical pick-up apparatuses which are the 2nd Embodiment of this invention. It is sectional drawing which shows the bearing component holding | maintenance part 26 used with the optical pick-up apparatus 1B which is the 3rd Embodiment of this invention. It is a figure which shows the bearing component holding | maintenance part 30 used with the optical pick-up apparatus 1C which is the 4th Embodiment of this invention. It is a figure which shows the bearing components holding part 38 used with the optical pick-up apparatus 1D which is the 5th Embodiment of this invention. It is a figure which shows the bearing components holding | maintenance part 50 used with the optical pick-up apparatus 1E which is the 6th Embodiment of this invention. It is sectional drawing which shows the bearing component holding part 60 used with the optical pick-up apparatus 1F which is the 7th Embodiment of this invention. It is a figure which shows the bearing components holding | maintenance part 65 used with the optical pick-up apparatus 1G which is the 8th Embodiment of this invention. It is a figure which shows the bearing components holding | maintenance part 70 used with the optical pick-up apparatus 1H which is the 9th Embodiment of this invention. It is a figure which shows the optical disk drive device 80 by a prior art. 2 is an external view of an optical pickup 84. FIG. 2 is an external view of a pickup base 87. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1A-1H Optical pick-up apparatus 2,53 Pickup base 3 Optical disk 4 Objective lens 10,20,26,30,38,50,60,65,70 Bearing component holding part 11,21,41,66,71 Holding Portions 12, 22, 27, 74 Semicircular concave portion 13 Straight portion 14 Bearing component 15 Guide shaft 23 Projection portion 28 Tapered rib 33 Grease holding rib 39 Arc-shaped concave portion 42 Other end portion 51 Bearing component holding component 52, 61 Bearing component Receiving part 62 Rib 72 Grease holding groove

Claims (8)

An optical pickup apparatus comprising: an objective lens that focuses laser light on a signal recording surface of an optical recording medium; an objective lens moving unit that moves the objective lens; and a pickup base that mounts the objective lens and the objective lens moving unit Because
The pickup base includes at least one guide shaft holding portion through which a guide shaft for moving the pickup base in the radial direction of the optical recording medium is inserted,
The guide shaft holding portion has at least three holding portions each having an arcuate recess having a central angle of 180 ° or less with respect to the same central axis as the guide shaft so that the guide shaft is sandwiched between the recesses. An optical pickup device having the same shape as that arranged on the surface. The same shape is a shape in which the at least three holding portions are arranged adjacent to each other in the central axis direction of the guide shaft,
The optical pickup device according to claim 1, wherein the guide shaft is inserted through a bearing member fitted into the guide shaft holding portion.   The optical pickup device according to claim 1, wherein the concave portion includes a protrusion whose top portion is in contact with the guide shaft.   The optical pickup device according to claim 2, wherein the concave portion includes a protrusion whose top portion is in contact with the bearing member.   The optical pickup device according to claim 2, wherein the guide shaft holding portion includes a bearing member removal preventing portion that prevents the bearing member from coming off from the guide shaft holding portion.   The optical pickup device according to claim 2, wherein the guide shaft holding portion includes a lubricant holding portion that prevents a lubricant applied to the bearing member from leaking.   2. The end of the at least three holding portions is separated on a plane that includes the central axis of the guide shaft and is substantially parallel to the radial direction of the optical recording medium. Optical pickup device.   The said guide shaft holding part is comprised from the part shape | molded integrally with the said pickup base, and the part shape | molded separately from the said pickup base, and can be attached or detached to the said pickup base, It is characterized by the above-mentioned. The optical pickup device according to any one of 1 to 7.

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