JPH1049882A - Optical pickup device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an optical pickup device in which a track is accessed surely, and whose readout performance is enhanced, by installing two feeding shafts at a feeding mechanism of the optical pickup, installing fitting racks at the shafts, and making the pitch of a tooth part at the feeding shaft larger than that of the feeding shaft. SOLUTION: Two feeding shafts 21 are installed at the feeding mechanism 20 of the optical pickup, and the center of gravity of the optical pickup is surrounded by the feeding mechanism 20 as to prevent a stick slip generated in its movement. In addition, fitting racks 22 are installed so as to face the feeding shafts 21, and every pitch P2 of a sheetlike tooth part 23 screwed to every feed shaft 21 is made a little larger than every pitch P1 of every feeding shaft 21. In addition, the fitting racks 21 are installed by applying a preload to the feeding shafts 21. Thereby, the backlash of every fitting rack 22 with reference to every feeding shaft 21 is eliminated, and the optical pickup can be fed precisely and smoothly. In addition, the optical pickup can be accessed surely up to a prescribed track, and the readout performance of the optical pickup is enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup for reading a recording signal of an optical disk, and more particularly to a feed mechanism of an objective lens for causing a laser spot to follow surface deviation or eccentricity of the optical disk.

[0002]

2. Description of the Related Art In an optical disk player using an optical disk as a recording medium, an optical pickup is used as means for reading and reproducing information signals recorded on the optical disk. The optical pickup focuses a laser beam emitted from a laser light source as a beam spot on a pit row, which is a minute unevenness formed on a signal recording surface of the optical disc, via an objective lens, and reflects the beam from the pit row. The information signal is read and reproduced by detecting the state of the reflected beam thus obtained with a photodetector.

When a laser beam is focused on the pit row of an optical disk as a beam spot via an objective lens, the optical axis of the objective lens is maintained exactly perpendicular to the signal recording surface of the optical disk. Without
An aberration occurs in the beam spot condensed on the pit row, and a noise component is superimposed on an information signal to be read and reproduced, thereby deteriorating reproduction characteristics, and depending on the degree, reading and reproduction of the information signal become impossible. Therefore, an optical pickup used in an optical disk player or an optical recording / reproducing apparatus is designed to apply the laser beam to the signal recording surface of the optical disk so that the laser beam always enters the signal recording surface of the optical disk exactly perpendicularly. Various types of objective lenses having a mechanism for adjusting the inclination of the optical axis of an objective lens for focusing light are used.

An example of a conventional optical pickup will be described with reference to FIG. 12A and 12B are diagrams showing a configuration of a conventional optical pickup, wherein FIG. 12A is a plan view and FIG. 12B is a front view. 6
Reference numeral 0 denotes an optical pickup device, which includes an optical pickup 65, a feed mechanism 90, and the like. The optical pickup 65 includes a movable section 70, a base 80, and the like.

The movable section 70 includes an objective lens 71, a focus adjustment coil and a tracking adjustment coil (all not shown), a wire 72, and the like. The movable portion 70 is elastically held on the upright portion 81 of the base 80 by four small-diameter wires 72 made of four elastic bodies (for example, phosphor bronze) fixed to two on each side. The objective lens 71 is a lens that converges the laser light emitted from the laser light source on the signal recording surface of the optical disc, and moves and adjusts the objective lens 71 in the focus direction when a focus direction adjustment signal is input to the focus adjustment coil. ,Also,
When an adjustment signal in the tracking direction is input to the tracking adjustment coil, the objective lens 71 is moved and adjusted in the tracking direction.

In the base 80, the other ends of the four wires 12 fixed to the side surfaces of the movable portion 70 are connected to the upright portions 81 of the base 80 (mounting holes and the like are formed as necessary).
, The movable portion 70 is elastically held on the base 80 by four wires 72, and a support portion 92 of the feed shaft 91 is formed. The feed mechanism 90 includes the optical pickup 65
Of the optical disk from the inner circumference to the outer circumference of the optical disk, and includes a feed shaft 91, a guide shaft 95, a fitting rack (not shown in detail), a drive mechanism (not shown), and the like.

The feed shaft 91 is a screw that is finished with high precision, is held by a bearing so as to be parallel to the surface of the optical disk, and is fixed to the housing (both are not shown). The guide shaft 95 is for preventing the center of the optical pickup 65 from shifting when the optical pickup 65 moves. The guide shaft 95 is held by a bearing 96 so that the precisely finished shaft is parallel to the feed shaft 91 in a pair, and is fixed to the housing (not shown). Have been.

The fitting rack 92 has a plate-like tooth portion screwed to the thread portion of the feed shaft 91, and is provided so that extra pressure is applied to the feed shaft 91 via a leaf spring or the like. ing.

[0009]

However, in the above-described feed mechanism 90 of the optical pickup 65, the optical pickup 65 is moved by a pair of the feed shaft 91 and the guide shaft 95. Optical pickup 65
Of the optical pickup 65
Moves to the inner and outer circumferences of the optical disc while repeating a linear movement in the inner and outer circumference directions of the optical disc along the guide shaft 95 and a rotational movement centered on the vicinity of the center of gravity of the optical pickup 65. In particular, when the movement (stick slip) occurs while repeating the latter rotational movement, a problem occurs such that the access to a predetermined track cannot be performed well and the operation of the feed servo becomes unstable. There is.

In view of the above, the present invention has been made to solve the above-mentioned problem, and provides an optical pickup in which a plurality of feed shafts are provided so as to sandwich the center of gravity of the optical pickup to minimize stick-slip generated when the optical pickup moves. The purpose is to do.

[0011]

According to the present invention, there is provided an optical pickup apparatus comprising: an optical pickup for reading a recording signal of an optical disk; and a feeder for moving the optical pickup. Has a plurality of feed shafts for moving the optical pickup from the inner circumference to the outer circumference of the optical disk.

A gear A fixed to the plurality of feed shafts, a gear B fixed to the rotating shaft of the motor,
A gear C meshes with both the gear A and the gear B, and the plurality of feed shafts are rotated in desired directions by rotating the motor. Also, a plurality of plate-like racks fixed to the optical pickup and formed at a pitch different from the pitch of the feed shaft are screwed to the feed shaft.

Further, the racks are arranged at positions facing each other with respect to the feed shaft. Further, the rack is characterized in that excess pressure is applied to the feed shaft.
Further, a center of gravity of the optical pickup is located within a range surrounded by the plurality of feed axes in a plane parallel to the optical disk.

In a plane perpendicular to the feed axis,
A center of gravity of the optical pickup is located within a range surrounded by the plurality of feed axes. Further, in an optical pickup device comprising an optical pickup for reading a recording signal of an optical disk and a feed device for moving the optical pickup, a plurality of feed shafts for moving the optical pickup from the inner circumference to the outer circumference of the optical disk; And a guide shaft of the optical pickup provided in parallel with the axis.

Further, the invention is characterized in that the guide shaft is provided within a range surrounded by the plurality of feed shafts in a plane parallel to the optical disk. Further, among the plurality of feed shafts, the guide shaft is provided at a position closer to the optical disk than the feed shaft provided farthest from the optical disk. .

The guide shaft is provided between the feed shaft provided at a position farthest from the optical disk and the feed shaft provided at the closest position among the plurality of feed shafts. It is characterized by doing so. Further, in an optical pickup device comprising an optical pickup for reading a recording signal of an optical disk and a feeding device for moving the optical pickup, an operating part comprising an objective lens, a focus adjustment coil and a tracking adjustment coil of the optical pickup is provided by four wires. A holding unit for elastically holding the optical pickup, a plurality of feed axes for moving the optical pickup from the inner circumference to the outer circumference of the optical disc, and a guide axis of the optical pickup provided in parallel with the feed axis,
In a plane parallel to the optical disc, between the wire fixing portion of the holding portion and the wire fixing portion of the movable portion,
The invention is characterized in that the guide shaft is provided.

A guide shaft is provided between two wires provided at a position closer to the optical disk and two wires provided at a position farther from the optical disk. It is characterized in that it is provided.

[0018]

FIG. 1, FIG. 2 and FIG. 3 show a first embodiment of the present invention.
This will be described with reference to FIG. FIG. 1 is a diagram showing a schematic configuration of an optical pickup device according to a first embodiment of the present invention, wherein FIG.
(B) is a front view. 2A and 2B are schematic diagrams showing a relationship between a feed shaft and a fitting rack according to the first embodiment of the present invention, wherein FIG. 2A is a plan view and FIG.

FIG. 3 is a plan view showing a drive mechanism of the feed shaft according to the first embodiment of the present invention. 5 is an optical pickup device,
The optical pickup 4 includes a movable section 10 and a base 1.
3 and the like. The movable section 10 of the optical pickup 4 includes an objective lens 11, a focus adjustment coil and a tracking adjustment coil (all not shown), a wire 1
2 and the like. The movable part 10 has four elastic bodies (for example, phosphor bronze) fixed to two on each side.
Of the base 13 with the extremely small diameter wire 12
It is held elastically. The objective lens 11 is a lens that converges the laser light emitted from the laser light source on the signal recording surface of the optical disc, and moves and adjusts the objective lens 11 in the focus direction when a focus direction adjustment signal is input to the focus adjustment coil. When an adjustment signal in the tracking direction is input to the tracking adjustment coil, the objective lens 11 is moved and adjusted in the tracking direction.

The base 13 has the other ends of the four wires 12 fixed to the side surfaces of the movable portion 10 and the upright portions 14 of the base 13 (mounting holes and the like are formed as necessary).
, The movable portion 10 is elastically held on the base 13 by four wires 12, and a support portion 15 of the feed shaft 21 is formed. The feed mechanism 20 is a feed mechanism 20 for moving the optical pickup 4 from the inner circumference to the outer circumference of the optical disk, and includes a feed shaft 21, a fitting rack 22, a drive mechanism 25, and the like.

The feed shaft 21 is a precisely finished screw, and the feed shaft 21 is held by a bearing so as to be parallel to the surface of the optical disk and fixed to the housing (both are not shown). The fitting rack 22 is formed with two plate-shaped teeth 23 that are screwed into the screw of the feed shaft 21. Tooth 23
Is different from the pitch P1 of the thread portion of the feed shaft 21 (for example, when the tooth portion 23 of the fitting rack 22 straddles one thread of the thread portion, the tooth pitch is larger than the pitch P1 of the thread portion. The pitch P2 of the portion 23 is formed slightly larger, and when two threads are straddled, the pitch P2 × 2 is formed slightly smaller than the pitch P1 × 2).
The fitting racks 22 face each other with respect to the feed shaft 21 (for example, the teeth 23 are provided from the inside of the feed shaft 21 to the outside. Alternatively, the teeth 23 are provided from the outside of the feed shaft 21 to the inside. To be provided.) Further, the fitting rack 22 is provided so that excess pressure is applied to the feed shaft 21 via a leaf spring or the like.

The drive mechanism 25 comprises a gear train in which a motor 26, a drive gear 27 inserted and fixed to a motor shaft, an intermediate two-stage gear 28, and a driven gear 29 inserted and fixed to a feed shaft are combined. . As described above, according to the present embodiment, by providing two feed shafts 21 in the feed mechanism 20 of the optical pickup 4, it is possible to prevent stick-slip occurring when the optical pickup 4 moves. Further, a fitting rack 22 is provided so as to face the feed shaft 21, and further, a plate-like tooth portion 23 screwed to the feed shaft 21.
Is slightly larger than the pitch P1 of the screw of the feed shaft 21, and the fitting rack 22 is provided with excess pressure applied to the feed shaft 21, so that the backlash between the feed shaft 21 and the fitting rack 22 is reduced. As a result, accurate and smooth feed can be performed, and the reading performance of the optical pickup 4 can be improved.

Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 4 is a plan view showing the relationship between the feed shaft and the center of gravity of the optical pickup according to the second embodiment of the present invention. The second
In the embodiment, the range of the position of the center of gravity of the optical pickup of the first embodiment is limited, and the rest is substantially the same as the configuration of the first embodiment. Therefore, the same components are denoted by the same reference numerals and description thereof is omitted. I do.

Numeral 30 indicates a range of the position of the center of gravity of the optical pickup 4, and within a plane parallel to the optical disk, 2 is indicated.
The position of the center of gravity of the optical pickup 4 is limited to the range indicated by oblique lines c, d, e, and f surrounded by the book feed shaft 21. As described above, according to the present embodiment, the two feed shafts 21 are arranged particularly when the optical pickup 4 is placed horizontally (the optical pickup 4 is in the horizontal direction).
In this case, no extreme offset load is applied, so that stick-slip can be prevented. Therefore, as in the first embodiment, the feed of the optical pickup 4 is accurate and smooth, and the reading performance of the optical pickup 4 can be improved.

Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 5 is a plan view showing the relationship between the feed shaft and the center of gravity of the optical pickup according to the third embodiment of the present invention. The third
In the embodiment, the range of the position of the center of gravity of the optical pickup of the first embodiment is limited, and the rest is substantially the same as the configuration of the first embodiment. Therefore, the same components are denoted by the same reference numerals and description thereof is omitted. I do.

Numeral 31 indicates the range of the position of the center of gravity of the optical pickup 4, and in the plane parallel to the optical disk, 2 indicates
The position of the center of gravity of the optical pickup 4 is limited to a range indicated by oblique lines g, h, i, and j surrounded by the feed shaft 21. As described above, according to the present embodiment, the two feed shafts 21 are arranged particularly when the optical pickup 4 is placed vertically (in the horizontal direction).
In this case, no extreme offset load is applied, so that stick-slip can be prevented. Therefore, as in the first embodiment, the feed of the optical pickup 4 is accurate and smooth, and the reading performance of the optical pickup 4 can be improved.

Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 6 is a plan view showing a schematic configuration of an optical pickup device according to a fourth embodiment of the present invention. In the fourth embodiment, a part of the first embodiment is changed, and the others are substantially the same as those of the first embodiment. .

Reference numeral 6 denotes an optical pickup device, which includes the optical pickup 4, the feed mechanism 20, a guide shaft 36, and the like. The optical pickup 4 includes the movable portion 10, the base 35, and the like. The base 35 includes the movable part 1
The other ends of the four wires 12 fixed to the side surface of the base 0 are fixed to the upright portions 14 (mounting holes and the like are formed as necessary) of the base 35, and the four movable portions 10 are provided. Elastically held on the base 35 by the wire 12 and the feed shaft 2
One support portion 15 and a support portion 37 for the guide shaft 36 are formed.

The guide shaft 36 prevents the center of the optical pickup 4 from shifting when the optical pickup 4 moves, and a precisely finished shaft is provided outside the two feed shafts 21 in parallel with the feed shafts 21. According to the present embodiment as described above,
The center shift can be prevented when the optical pickup 4 moves. Therefore, as in the first embodiment, the feed of the optical pickup 4 becomes more accurate and smooth, and the reading performance of the optical pickup 4 can be improved.

Next, a fifth embodiment of the present invention will be described with reference to FIG. FIG. 7 is a plan view showing a schematic configuration of an optical pickup device according to a fifth embodiment of the present invention. In the fifth embodiment, a part of the fourth embodiment is changed, and the others are substantially the same as those of the fourth embodiment. .

Reference numeral 7 denotes an optical pickup device, which includes the optical pickup 4, the feed mechanism 20, the guide shaft 36, and the like. The optical pickup 4 includes the movable portion 10, the base 38, and the like. The base 38 includes the movable part 1
The other ends of the four wires 12 fixed to the side surfaces of the bases 0 are fixed to the upright portions 14 of the base 38 (mounting holes and the like are formed as necessary), and the four movable portions 10 are provided. Elastically held on the base 38 by the wire 12 and the feed shaft 2
One support portion 15 and a support portion 37 for the guide shaft 36 are formed.

The guide shaft 36 prevents the center of the optical pickup 4 from shifting when the optical pickup 4 moves. The guide shaft 36 has a precisely finished shaft surrounded by two feed shafts 21 in a plane parallel to the optical disk. And are provided in parallel.
As described above, according to this embodiment, stick slip can be prevented when the optical pickup 4 moves. Therefore, as in the first embodiment, the optical pickup 4
Is more accurate and smooth, and the reading performance of the optical pickup 4 can be improved.

Next, a sixth embodiment of the present invention will be described with reference to FIG. FIG. 8 is a side view showing a relationship between a feed shaft and a guide shaft according to a sixth embodiment of the present invention. The sixth embodiment is the fourth embodiment.
Since the range of the set position of the guide shaft of the embodiment is limited, and the other portions are substantially the same as the configuration of the fourth embodiment, the same components are denoted by the same reference numerals and description thereof is omitted.

Numeral 40 denotes a range of the set position of the guide shaft 36. In the plane parallel to the optical disk 3, the feed shaft 21 farthest from the optical disk 3 among the two feed shafts 21 is shown.
And the setting range of the guide shaft 36 is limited to the range indicated by oblique lines of k, l, m, and n surrounded by the lower surface of the optical disk 3. As described above, according to the present embodiment, the two feed shafts 21 are arranged particularly when the optical pickup 4 is placed horizontally (the optical pickup 4 is in the horizontal direction).
In this case, no extreme offset load is applied, so that stick-slip can be prevented. Therefore, as in the fourth embodiment, the feed of the optical pickup 4 is accurate and smooth, and the reading performance of the optical pickup 4 can be improved.

Next, a seventh embodiment of the present invention will be described with reference to FIG. FIG. 9 is a side view showing a relationship between a feed shaft and a guide shaft according to a seventh embodiment of the present invention. The seventh embodiment is the fourth embodiment.
Since the range of the set position of the guide shaft of the embodiment is limited, and the other portions are substantially the same as the configuration of the fourth embodiment, the same components are denoted by the same reference numerals and description thereof is omitted.

Reference numeral 41 denotes a range of the set position of the guide shaft 36. In the plane parallel to the optical disc 3, the guide is set within the range indicated by oblique lines o, p, q, and r surrounded by the two feed shafts 21. The setting range of the axis 36 is limited. As described above, according to the present embodiment, no extreme eccentric load is applied to the two feed shafts 21 particularly when the optical pickup 4 is placed vertically (in the vertical direction), so that stick-slip can be prevented. Therefore, as in the fourth embodiment, the feed of the optical pickup 4 is accurate and smooth, and the reading performance of the optical pickup 4 can be improved.

Next, an eighth embodiment of the present invention will be described with reference to FIG. FIG. 10 is a plan view showing the range of the set position of the guide shaft according to the eighth embodiment of the present invention. In the eighth embodiment, the range of the set position of the guide shaft of the fourth embodiment is limited, and the other configuration is substantially the same as that of the fourth embodiment. And the description is omitted.

Reference numeral 8 denotes an optical pickup device, which includes the optical pickup 4, the feed mechanism 20, a guide shaft 36, and the like. The optical pickup 4 includes the movable portion 10, the base 45, and the like. The base 45 includes the movable part 1
The other ends of the four wires 12 fixed to the side surfaces of the base 45 are fixed to the erected portions 14 of the base 45 (where attachment holes and the like are formed as necessary), and the four movable portions 10 are provided. Elastically held on the base 45 by the wire 12 and the feed shaft 2
The first support portion 15 and the support portion 37 of the guide shaft 36 are formed.

Reference numeral 42 denotes the range of the set position of the guide shaft 36. In the plane parallel to the optical disk 3, the fixed portions s and t of the movable portion 10 and the wire 12 and the other fixed portions u and The guide shaft 3 is set within the range indicated by the hatching
6, the setting range is limited. As described above, according to the present embodiment, the size of the optical pickup device 8 in the tangential direction can be reduced. Further, when the optical pickup device 8 is placed horizontally (the optical pickup device 8 is in the horizontal direction), no extreme eccentric load is applied to the two feed shafts 21, so that stick-slip can be prevented. Therefore, as in the fourth embodiment, the feed of the optical pickup 4 is accurate and smooth, and the reading performance of the optical pickup 4 can be improved.

Next, a ninth embodiment of the present invention will be described with reference to FIG. FIG. 11 is a plan view showing the range of the set position of the guide shaft according to the ninth embodiment of the present invention. In the ninth embodiment, the range of the set position of the guide shaft of the eighth embodiment is changed, and the other configurations are substantially the same as those of the eighth embodiment. And the description is omitted.

Reference numeral 9 denotes an optical pickup device, which comprises an optical pickup 4, a feed mechanism 20, a guide shaft 36, and the like. The optical pickup 4 comprises a movable portion 10, a base 45, and the like. Reference numeral 43 denotes a range of the set position of the guide shaft 36. In the plane parallel to the optical disk 3, the end surface 46 of the movable portion 10 and the upper and lower wires 12
The range of the guide shaft 36 is limited to the range shown by the oblique line surrounded by the intersections y and z between the intersections w and x with the upper and lower wires 12 and the end surface 47 of the standing portion of the base 45.

As described above, according to the present embodiment, the thickness of the optical pickup device 9 can be reduced. In addition, when the optical pickup device 9 is placed vertically (horizontal direction), no extreme eccentric load is applied to the two feed shafts 21, so that stick-slip can be prevented. Therefore, as in the fourth embodiment, the feed of the optical pickup 8 is accurate and smooth, and the reading performance of the optical pickup 8 can be improved.

[0043]

As described above, according to the present invention, since the feed shaft is provided so that the center of gravity of the optical pickup is within the range surrounded by the plurality of feed shafts, the stick slip generated when the optical pickup moves. Can be minimized. Therefore, the access to the predetermined track by the optical pickup is ensured, and the operation of the feed servo is stabilized, so that the reading performance of the optical pickup can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of an optical pickup device according to a first embodiment of the present invention, wherein (a) is a plan view and (b) is a front view.

FIGS. 2A and 2B are schematic diagrams showing a relationship between a feed shaft and a fitting rack according to the first embodiment of the present invention, wherein FIG. 2A is a plan view and FIG.

FIG. 3 is a plan view showing a feed shaft driving mechanism according to the first embodiment of the present invention.

FIG. 4 is a plan view illustrating a relationship between a feed shaft and a center of gravity of an optical pickup according to a second embodiment of the present invention.

FIG. 5 is a plan view showing a relationship between a feed shaft and a center of gravity of an optical pickup according to a third embodiment of the present invention.

FIG. 6 is a plan view showing a schematic configuration of an optical pickup device according to a fourth embodiment of the present invention.

FIG. 7 is a plan view showing a schematic configuration of an optical pickup device according to a fifth embodiment of the present invention.

FIG. 8 is a side view showing a relationship between a feed shaft and a guide shaft according to a sixth embodiment of the present invention.

FIG. 9 is a side view showing a relationship between a feed shaft and a guide shaft according to a seventh embodiment of the present invention.

FIG. 10 is a plan view showing a range of a set position of a guide shaft according to an eighth embodiment of the present invention.

FIG. 11 is a side view showing a range of a set position of a guide shaft according to a ninth embodiment of the present invention.

FIG. 12 is a diagram showing a schematic configuration of a conventional optical pickup device, wherein (a) is a plan view and (b) is a front view.

[Explanation of symbols]

3 Optical disk 4 Optical pickup 5, 6, 7, 8, 9 Optical pickup device 10 Movable section 11 Objective lens 12 · Wires 13, 35, 38, 45 · · · Base 14 · · · Standing part 15 · · · Feed shaft support part 20 · · · Feed mechanism 21 · · · · Feed shaft 22 · · · ··· Fitting rack 23 ···· Tooth 25 ··· Drive mechanism 26 ··· Motor 27 ··· Drive gear 28 ··· Intermediate two-step gear 29 ··· ··· Driven gears 30 and 31 ··· Limited range of the position of the center of gravity of the optical pickup 36 ········ Guide shaft 37 ··· Limited range 46, 47 ... end face

Claims (13)

[Claims] 1. An optical pickup device comprising: an optical pickup for reading a recording signal of an optical disk; and a feeding device for moving the optical pickup, wherein the feeding device moves the optical pickup from an inner circumference to an outer circumference of the optical disk. An optical pickup device having a plurality of feed shafts. 2. A gear A fixed to the plurality of feed shafts, a gear B fixed to a rotating shaft of a motor, and a gear C meshing with both the gears A and B, 2. The optical pickup device according to claim 1, wherein the plurality of feed shafts are rotated in a desired direction by rotating a motor. 3. A plurality of plate-like racks fixed to the optical pickup and formed at a pitch different from the pitch of the feed shaft are screwed to the feed shaft. An optical pickup device as described in the above. 4. The optical pickup device according to claim 3, wherein the racks are arranged at positions facing each other with respect to the feed shaft. 5. The optical pickup device according to claim 3, wherein the rack is applied with excess pressure on the feed shaft. 6. In a plane parallel to the optical disk,
2. The optical pickup device according to claim 1, wherein a center of gravity of the optical pickup is located within a range surrounded by the plurality of feed axes. 7. The optical pickup according to claim 1, wherein the position of the center of gravity of the optical pickup is located within a range surrounded by the plurality of feed axes in a plane perpendicular to the feed axis. Optical pickup device. 8. An optical pickup device comprising: an optical pickup for reading a recording signal of an optical disk; and a feed device for moving the optical pickup, wherein a plurality of feed shafts for moving the optical pickup from the inner periphery to the outer periphery of the optical disk. An optical pickup device, comprising: a guide shaft of the optical pickup provided in parallel with the feed shaft. 9. In a plane parallel to the optical disk,
9. The optical pickup device according to claim 8, wherein the guide shaft is provided within a range surrounded by the plurality of feed shafts. 10. The guide shaft is provided at a position closer to the optical disc than the feed shaft provided farthest from the optical disk among the plurality of feed shafts. An optical pickup device according to claim 8. 11. The guide shaft is provided between the feed shaft provided farthest from the optical disk and the feed shaft provided closest to the optical disk among the plurality of feed shafts. 9. The optical pickup device according to claim 8, wherein: 12. An optical pickup device comprising: an optical pickup for reading a recording signal of an optical disk; and a feeding device for moving the optical pickup, wherein an operating part comprising an objective lens, a focus adjustment coil and a tracking adjustment coil of the optical pickup is provided. A holding unit for elastically holding the wire, a plurality of feed axes for moving the optical pickup from the inner circumference to the outer circumference of the optical disc, and a guide axis of the optical pickup provided in parallel with the feed axis. In a plane parallel to the optical disk, between the wire fixing portion of the holding portion and the wire fixing portion of the movable portion,
An optical pickup device, wherein the guide shaft is provided. 13. A guide shaft is provided between two wires provided at a position closer to the optical disk and two wires provided at a position farther from the optical disk among the four wires. 13. The optical pickup device according to claim 12, wherein the optical pickup device is provided.