JPH08315522A - Optical recorder/reproducer - Google Patents

Abstract

PURPOSE: To obtain a simple structure for eliminating the rattling of carriage. CONSTITUTION: A carriage 4 carrying an optical head 2 is fixed slidingly to one 25 of two parallel guide shafts 25, 26 through a thrust bearing 34. A deformed radial bearing 35 fixed rotatably to the carriage 4 has a seesaw type rotary arm 37 and a pair of rollers 39 disposed at the opposite ends thereof, is pressed against the opposite sides of the other guide shaft 26 by means of a tension coil spring 40 for urging the rotary arm 37 to rotate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical recording / reproducing apparatus for optically recording / reproducing information on / from an optical disc by an optical head, and more particularly, for linearly moving the optical head along the radiation from the center of the optical disc. It is related to the moving mechanism of.

[0002]

2. Description of the Related Art Conventionally, in this type of optical recording / reproducing apparatus, as shown in FIG. 11, an optical disk 1 is rotationally driven at a high speed by a spindle motor (not shown) while an objective lens 3 of an optical head 2 is used. Recording surface 1 of optical disc 1
While irradiating laser beam LB to a, the optical head 2
Recording and reproduction are performed on the optical disc 1 by linearly moving the carriage 4 in the directions of arrows a and b along the radiation P ₂ from the center of the optical disc 1.

Then, as shown in FIG. 11, a conventional basic optical head moving mechanism 5 for linearly moving the optical head 2 in the directions of arrows a and b along the radiation P _{2 of the} optical disk 1 is provided at the upper part. Carriage 4 with optical head 2 mounted
One end side 4a of the carriage is slidably inserted into the outer circumference of one guide shaft 7 parallel to the optical disk 1 and parallel to the radiation P ₂ by two thrust bearings 7 using linear ball bearings. The other end side 4b of 4 is mounted rotatably along a guide rail 9 parallel to the guide shaft 7 by a roller 8 using a ball bearing, and a roller pressing rail 10 parallel to the guide rail 9 is used to roll the roller 8 Prevents floating.

Further, as shown in FIG. 12, an improved optical head moving mechanism 5 of the related art is provided with both ends 4 of the carriage 4.
A pair of upper and lower ball bearings, a total of six rollers 8 are provided at three locations a and 4b with respect to the vertical reference line.
It is mounted at an angle of 5 °, and these rollers 8 are slidably abutted on the upper and lower sides inside the two parallel guide shafts 7 and 11, so that the carriage 4 can be rolled between these two guide shafts 7. Has been installed in. Then, in order to prevent the carriage 4 from falling off between the two guide shafts 7 and 11 and to eliminate rattling, one guide shaft 11 is directed parallel to the other guide shaft 7 side by a strong leaf spring 12 in the arrow e direction. It always gives a strong preload to press.

In any of the optical head moving mechanisms 5 shown in FIGS. 11 and 12, the carriage 4 is moved along the guide shaft 7 by an arrow a by a linear motor (not shown) using a magnetic circuit and a voice coil. , B so that the optical head 2 is linearly driven along the radiation P ₂ along the arrows a, b.
It is configured to move linearly in the direction.

[0006]

However, in the basic optical head moving mechanism 5 shown in FIG. 11, the linear movement of the carriage 4 in the directions of the arrows a and b is smooth, while the guide rail 9 and the roller pressing rail. Due to the rattling of the roller 8 between 10 and 10, it is vertical to the carriage 4 (direction of arrow g).
Since it causes backlash, it is weak against external disturbance (vibration or shock applied from the outside) and lacks reliability. Therefore, there is a problem that it is not particularly suitable for an optical recording / reproducing apparatus that simultaneously records and reproduces the double-sided optical disc 1 from above and below by using two sets of optical heads 2 at the top and bottom.

The improved optical head moving mechanism 5 shown in FIG. 12 has a vertical direction (direction of arrow g) of the carriage 4.
While the positioning in the horizontal direction (the direction of arrow h) can be reliably performed, the number of parts and the number of assembling steps are large, resulting in a significantly high cost. Further, since the one guide shaft 11 is always given a strong preload in the direction of arrow e, a linear motor having a large load and a large driving torque is required for the linear movement of the carriage 4 in the directions of arrows a and b. Further, there is a problem that the contact surface between the total of six rollers 8 and the two guide shafts 7 and 11 progresses rapidly and lacks durability.

The present invention has been made to solve the above problems, and provides an optical recording / reproducing apparatus having a simple structure in which the linear movement of the carriage is smooth and the rattling of the carriage can be eliminated. It is intended to be provided.

[0009]

An optical recording / reproducing apparatus of the present invention for achieving the above object is provided with two parallel guide shafts for guiding a carriage on which an optical head is mounted, and one guide shaft is provided. For the shaft, a carriage is slidably attached using a thrust bearing, and for the other guide shaft, a seesaw type rotary arm rotatably attached to the carriage via a rotation center shaft, and its Using a modified radial bearing composed of a pair of rollers rotatably attached to both ends of the rotary arm and a rotation biasing means for biasing the rotary arm in one direction, the pair of rollers of this modified radial bearing are The other guide shaft is crimped to both upper and lower sides.

[0010]

In the optical recording / reproducing apparatus of the present invention configured as described above, the carriage on which the optical head is mounted uses the thrust bearing for one of the two parallel guide shafts. A pair of rollers at both ends of a seesaw type rotary arm of a deformed radial bearing, which is slidably attached to the other guide shaft, is rotatably attached to the other guide shaft by the rotation biasing means of the rotary arm. Since the guide shafts are crimped to the upper and lower sides, rattling in the horizontal and vertical directions of the carriage can be eliminated by the thrust bearing and the deformed radial bearing, and the carriage can be smoothly moved linearly along the two guide shafts. .

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an optical recording / reproducing apparatus to which the present invention is applied will be described below with reference to FIGS. In addition,
The same reference numerals are given to the same structural portions as those in FIGS. 11 and 12, and duplicate description will be omitted.

[General Description of Optical Head Moving Mechanism] First,
The outline of the optical head moving mechanism 21 will be described with reference to FIG.

The optical head moving mechanism 21 has an optical head 2 mounted on an upper part of a carriage 4 via an optical head mount 22, and the optical head 2 has a rotation direction (arrow i) with respect to an objective lens 3 in the optical head 2. The optical sensor 23 of the light reflection type for detecting the sagging of the outer periphery 1b of the optical disc 1 is mounted in the vicinity of the upstream side in the (direction).
The optical disc 1 is horizontally mounted on the spindle motor 24 and is rotationally driven at a high speed in the arrow i direction.

On both sides of the carriage 4, two guide shafts 25 and 26, which are parallel to the recording surface 1a of the optical disk 1 and the radiation P ₂ from the center O ₁ , are arranged horizontally. Both ends of these guide shafts 25 and 26 in the lengthwise direction are fixed onto a chassis (not shown).

The carriage 4 is constructed to be linearly moved between the two guide shafts 25 and 26 in the directions of arrows a and b by being guided by the guide shafts 25 and 26. The objective lens 3 of the optical head 2 mounted on the carriage 4 is linearly moved in the directions of arrows a and b along the radiation P ₂ from the center O _{1 of the} optical disc 1.

A linear motor 27 for linearly driving the carriage 4 in the directions of arrows a and b has a voice coil 29 attached to one end of the carriage 4 via a coil attachment plate 28, a pair of upper and lower yokes 30, and one of the yokes. York 30
Magnetic circuit 3 consisting of magnets 31 stacked inside the
2 and. The pair of upper and lower yokes 30 and the magnet plate 31 are fixed on the chassis in a horizontal state parallel to the guide shafts 25 and 26. The voice coil motor is configured to linearly drive the carriage 4 in the directions of arrows a and b by the driving force generated between the voice coil 29 and the magnetic circuit 32.

[Description of Thrust Bearing and Modified Radial Bearing] Next, the thrust bearing 34 and the modified radial bearing 35 of the carriage 4 will be described with reference to FIGS.

First, the moving direction of the carriage 4 (arrow a,
One end 4a in the direction (arrow h direction) perpendicular to the b direction)
A pair of thrust bearings 34 using linear ball bearings are embedded in the same axis line, and these thrust bearings 34 are slidably inserted into the outer periphery of one guide shaft 25.

Next, the other end 4 of the carriage 4 in the direction of arrow h
A modified radial bearing 35 is attached to the vertical side surface 4c of b. The modified radial bearing 35 is a seesaw type rotary arm 37 rotatably attached to a vertical side surface 4 c of the carriage 4 via a horizontal rotation center shaft 36.
And a pair of upper and lower rollers 39 using ball bearings rotatably attached to the side surfaces of both ends of the rotating arm 37 via a pair of horizontal support shafts 38.

A tension coil spring 40, which is a rotation urging means installed between the rotary arm 37 and the other end 4b of the carriage 4, rotates the rotary arm 37 around the rotation center axis 36 in the direction of arrow j. By urging, the pair of upper and lower rollers 39 are pressed against the upper and lower sides of the other guide shaft 26 so as to be rollable in the direction of arrow j.

At this time, the two guide shafts 25 and 26 are mounted with high precision on a chassis (not shown) which is processed with high precision, and the recording surface 1a of the optical disc 1 and the center O _1.
The parallelism of the two guide shafts 25 and 26 with respect to the radiation P ₂ from the
The optical disc 1 has a horizontal reference plane P ₃ connecting the centers of 5 and 26.
Is set in a completely parallel state with respect to the recording surface 1a.

Therefore, the center of rotation O ₂ of the rotary arm 37 of the deformed radial bearing 35 is set on the horizontal reference plane P ₃ , and the center of rotation O ₂ of the rotary arm 37 is set to the center of rotation O of the pair of upper and lower rollers 39. The distance L ₁ to ₃ is configured to be equal.

According to the optical head moving mechanism 21 configured as described above, the two guide shafts 25 for the radiation P ₂ from the recording surface 1a of the optical disc 1 and the center O ₁ ,
The parallelism of 26 is set with high accuracy, and the horizontal reference plane P ₃ connecting the centers of these two guide shafts 25 and 26 is set to be completely parallel to the recording surface 1 a of the optical disc 1. since the optical axis F ₁ of the objective lens 3 with respect to radiation P ₂ from the center O ₁ of the distance L ₂ and the optical disk 1 of the objective lens 3 of the optical head 2 with respect to the recording surface 1a of the optical disk 1
The mounting accuracy of the optical head 2 in the vertical direction (direction of arrow g) and the horizontal direction (direction of arrow h) with respect to the optical disc 1 such as positioning of the carriage is determined by the mounting accuracy of the carriage 4 with respect to these two guide shafts 25 and 26. .

At this time, since the one end 4a of the carriage 4 is slidably inserted into the outer circumference of one guide shaft 25 by the thrust bearing 34, the carriage 4 is horizontally oriented with respect to the two guide shafts 25 and 26 (arrows). There is no rattling in the h direction) and the horizontal mounting accuracy is set to high accuracy.

The other end 4b of the carriage 4 is provided with a pair of upper and lower rollers 39 at both ends of the rotary arm 37 of the deformable radial bearing 35 by means of a tension coil spring 40.
The upper and lower sides of 6 are crimped simultaneously from the direction of arrow j.
Then, the pair of upper and lower rollers 39 is used for the other guide shaft 36.
At the same time when pressure is applied to both upper and lower sides of the
Rattling in the vertical direction (direction of arrow g) of the carriage 4 with respect to the two guide shafts 25 and 26 is eliminated.

Moreover, at this time, since the distance L ₁ from the rotation center O ₂ of the rotating arm 37 to the rotation center O ₃ of the pair of upper and lower rollers 39 is made equal, a pair of upper and lower rollers 39 is provided.
Is simultaneously crimped to the upper and lower sides of the other guide shaft 36 from the direction of the arrow j, and when the rattling of the carriage 4 disappears, the rotation center O ₂ of the rotation arm 37 moves between the centers of the two guide shafts 35 and 36. The carriage 4 is automatically positioned on the connecting horizontal reference plane P ₃ , and the mounting accuracy of the carriage 4 on the two guide shafts 25 and 26 in the vertical direction (direction of arrow g) is also set with high accuracy.

As a result of the above, this optical head moving mechanism 21
Is capable of accurately positioning the optical head 2 mounted on the carriage 4 with respect to the optical disk 1 in a vertical direction (arrow g direction) and a horizontal direction (arrow h direction) without any rattling. it can.

Moreover, the optical head moving mechanism 21 is
Two parallel guide shafts 25 and 26 fixed to the chassis
The carriage 4 is attached to the pair of thrust bearings 34 and the deformable radial bearings 35 so as to be linearly moved in the directions of arrows a and b. Therefore, the number of parts and the number of assembling steps are small, and the structure is simple.

According to the optical head moving mechanism 21, the modified radial bearing 35 positions the carriage 4 in the vertical direction (direction of arrow g), but the modified radial bearing 35 is positioned in the horizontal direction (arrow). Since there is no positioning function in the h direction), the linear motor 2
When the carriage 4 is linearly driven in the directions of arrows a and b along the two guide shafts 25 and 26 by 7, the upper and lower rollers 39 of the pair of thrust bearings 34 and the modified radial bearings 35 are not subjected to a large load.

Therefore, the linear drive of the carriage 4 in the directions of the arrows a and b can be performed extremely smoothly, and the contact surfaces between the pair of upper and lower rollers 39 and the guide shaft 26 are less worn and the durability is improved. Since the driving torque of the linear motor 27 can be reduced, the linear motor 2
7 can be made smaller and lighter, and the overall size and weight of the optical recording / reproducing apparatus can be promoted.

From the above point of view, according to the optical head moving mechanism 21, as shown in FIG. 5, the optical head moving mechanism 21 is symmetrical with respect to the upper and lower sides of the optical disc 1 having the recording surface 1a on both upper and lower sides. It is optimal for an optical recording / reproducing apparatus in which the upper and lower recording surfaces 1a of the optical disc 1 are arranged and simultaneously recorded and reproduced by the upper and lower optical heads 2.

That is, in particular, since the deformed radial bearing 35 can completely eliminate the vertical rattling of the carriage 4, even if the optical head moving mechanisms 21 having the same structure are arranged symmetrically above and below the optical disk 1, the carriage can be prevented. Four
No vertical rattling occurs, and the optical head moving mechanism 21 having the same structure can be shared.

[Description of Skew Adjusting Mechanism and Radial Dependence Adjusting Mechanism] Next, referring to FIGS. 1, 4, and 6 to 10, the skew adjusting mechanism 43 and the radial dependency of the optical head 2 will be described. The adjusting mechanism 53 will be described.

First, the optical head 2 mounted on the carriage 4 is attached to the upper part of the optical head mount 22 in a state in which the verticality can be adjusted by a plurality of spring adjusting screws 42.

First, the skew adjusting mechanism 43 supports both ends of the skew shaft 45 by a pair of skew shaft supporting members 44, and the skew shaft 45 is horizontally above the carriage 4 and has two guide shafts 25. , 26 at right angles. Then, a pair of shaft insertion holes 46 integrally formed in the lower portions of the left and right ends 22a and 22b of the optical head mount 22 are inserted into the outer periphery of the skew shaft 45 in the vicinity of both ends, and the optical head mount 22 is mounted on the skew shaft 45. The optical head mounting base 22 is mounted so as to be freely rotatable in the directions of arrows c and d, and is slidable in the directions of arrows e and f along the skew axis 45.

A skew adjusting mechanism 43 for rotating and adjusting the optical head mount 22 around the skew axis 45 in the directions of arrows c and d includes a geared motor 47 which is a motor mounted on one end 4a side of the carriage 4. The geared motor 47 has a first cam mechanism 48 that is driven to rotate forward and backward.

The first cam mechanism 48 is composed of a cam 49 composed of an eccentric rotation shaft, and a cam driven hole 50 inserted into the outer periphery of the cam 49.
Then, the cam 49 is rotatably mounted on the carriage 4 in parallel with the skew axis 45 and at a distance, and a cam driven hole 50 formed in the lower portion of the optical head mount 22 on the side of the one end 22a is provided on the outer periphery of the cam 49. It is inserted at a right angle. The output shaft 47a of the geared motor 47 and the cam 4
A shaft joint 51 is detachably connected to one end of the cam 9, and the cam 49 is eccentrically rotated by the output shaft 47a.

Next, the radial dependency adjusting mechanism 53 has a second cam mechanism 57 which is driven on the output side of the cam 49 of the skew adjusting mechanism 43 via a worm gear device 54 which is a speed reducing means. The second cam mechanism 57
Is a cam driven lever 59 which is rockably driven by a cam 58.
The optical head mount 22 is slidably adjusted along the skew axis 45 in the directions of arrows e and f.

The worm gear device 54 includes a cam 49
On the output side, the worm 55 is integrally formed around the rotation center of the cam 49, and the worm wheel 56 is meshed with the worm 55 at a right angle. The end of the worm 55 on the side opposite to the cam 49 is rotatably supported horizontally by a support shaft 64 mounted horizontally on the carriage 4, and the worm wheel 56
Is rotatably supported horizontally on the outer circumference of a support shaft 65 mounted vertically on the carriage 4. The reduction ratio of the worm gear device 54 is 1 / N, where N is the number of teeth of the worm wheel.

The second cam mechanism 57 has a cam 58 formed of an eccentric rotating wheel on the lower surface of the worm wheel 56.
Cam follower lever 5 that is integrally molded to form an almost L shape
9 is rotatably mounted horizontally on the outer periphery of a support shaft 66 mounted vertically on the carriage 4. Then, the cam 58 is inserted into a cam driven hole 60 formed at one end 59a of the cam driven lever 59, and the other end 59 of the cam driven lever 59 is inserted.
A drive pin 61, which is integrally formed vertically on the upper part of b, is inserted from below into an elongated hole 62 formed substantially in the center of the optical head mount 22. The long hole 62 is perpendicular to the skew axis 45.

Therefore, the first and second cam mechanisms 48, 5
7 is compactly housed in a small space between the carriage 4 and the optical head mount 22. As shown by the alternate long and short dash line in FIG. 7, the worm wheel 56 and the cam driven lever 59 are supported on the carriage 4 by means of a substantially T-shaped holding plate 67 made of a thin metal plate, which supports the support shafts 65, 66. Is pressed from above.

The optical head mount 22 is placed in the small space between the carriage 4 and the optical head mount 22.
A total of four vertical compression coil springs 68 for eliminating rattling in the directions of the arrows c and d around the skew axis 45 are interposed in a state where initial compression stress is applied. A horizontal compression coil spring 69 for eliminating rattling in the directions of the arrows e and f along the skew axis 45 of the optical head mount 22 is formed on the carriage 4 and below the optical head mount 22 as a pair of springs. It is interposed between the support portions 70 and 71 in parallel with the skew axis 45 and in a state where an initial compressive stress is applied.

[Description of Geared Motor Control Circuit] Next, referring to FIG. 9, a control circuit 73 for the geared motor 47 will be described.
Will be described. First, as described above, the optical disc 1 is located near the upstream side of the objective lens 3 in the optical head 2 in the rotation direction of the optical disc 1 (direction of arrow i).
Optical sensor 23 of the light reflection type for detecting the dripping of the outer periphery 1b
Is mounted, and the optical sensor 23 is provided with a two-part photodetector 74. And the optical sensor 23
4, the detector DB is irradiated onto the recording surface 1a of the optical disc 1 and the reflected light is received by the two-divided photodetector 74, depending on the degree of sag of the outer periphery 1b of the optical disc 1. , Each divided area 74A of the two-divided photodetector 74,
The received light amounts A and B at 74B reversibly change, and the detection output proportional to the difference between the received light amounts A and B at the respective divided areas 74A and 74B causes the recording surface 1a of the optical disc 1 shown in FIG.
The skew detection circuit (not shown) detects the amount and direction of the inclination θ of the normal line P ₁ perpendicular to.

Then, the control circuit 73 controls the amount of received light A in each of the divided areas 74A and 74B of the two-divided photodetector 74,
The detection outputs SA and SB proportional to B are respectively fed to the amplifier 7
Input to the arithmetic circuit 76 through 5A and 75B, and the arithmetic circuit 76 calculates SA-SB / SA + SB. The geared motor 47 is driven through the drive circuit 77 based on the calculated output.

At this time, the geared motor 47 is rotationally controlled in proportion to SA-SB which is the difference between the respective detection outputs, and SA
Feedback is applied so that −SB = 0. Then, by setting SA-SB = 0, the optical axis F ₁ of the laser beam LB emitted from the objective lens 3 in the optical head 2 shown in FIG. 8 to the recording surface 1a of the optical disc 1 coincides with the normal line P _1. Will be.

The skew adjusting mechanism 43 and the radial dependency adjusting mechanism 53 configured as described above.
According to the above, according to the skew adjustment mechanism 43, as shown in FIGS. 6 and 7, at the time of radial adjustment adjustment at the time of assembling adjustment on the manufacturing line of the optical recording / reproducing apparatus.
The geared motor 47 is a motor forward and reverse rotation control to be rotated normally and reversely control worm wheel 56 in the arrow e _1, f ₁ direction by the worm 55 integral with the cam 49.

Then, the cam 58 in the cam driven hole 60 of the second cam mechanism 57 is rotationally controlled in the same direction as the forward / reverse rotation, and the cam driven lever 59 is rotationally controlled in the directions of the arrows e ₂ and f ₂ , The drive pin 61 of the cam driven lever 59 drives the elongated hole 62 of the optical head mount 22 in the same direction, and the optical head mount 62 is slidably adjusted along the skew axis 45 in the directions of arrows e and f. .

Then, the optical axis F ₁ of the objective lens 3 in the optical head 2 mounted on the optical head mounting base 22.
Are automatically positioned on the radiation P ₂ from the center O _{1 of the} optical disc 1.

On the other hand, at the time of skew adjustment during recording and reproduction of the optical disk 1, the control circuit 73 described above controls the geared motor 47 to rotate forward and backward as shown in FIGS. The cam 49 in the cam driven hole 50 at 48 is controlled to rotate forward and backward in the directions of arrows c ₁ and d ₁ .

Then, the optical head mount 22 is controlled to rotate about the skew axis 45 in the directions of arrows c and d, and the optical axis F of the laser beam LB emitted from the objective lens 3 to the recording surface 1a of the optical disc 1 is controlled. ₁ is the outer circumference 1a of the optical disc 1.
Skew adjustment is performed so as to automatically follow the normal P ₁ that forms the inclination θ according to the drooping of.

During this skew adjustment, the worm 55 is integrally rotated with the cam 49 in the directions of arrows c ₁ and d _1, so that the worm wheel 56 also has an arrow e.
_The optical head mounting base 22 is finely moved in the directions of ₁ and f ₁ to be finely moved in the directions of arrows e and f. However, the reduction ratio of the worm gear device 54, which is the reduction mechanism including the worm 55 and the worm wheel 56, is Since the worm wheel 56 has a very large reduction ratio of 1 / the number of teeth, the fine movement phenomenon of the optical head mount 22 in the directions of the arrows e and f can be almost ignored functionally.

Further, the first cam mechanism 48 of the skew adjusting mechanism 43 and the radial dependency adjusting mechanism 53.
The operation of the second cam mechanism 57 is cyclic (circulation type), and has a safety structure that does not apply an overcurrent to the geared motor 47.

With the skew mechanism 43 and the radial dependency adjusting mechanism 53, the optical axis F ₁ of the objective lens 3 in the optical head 2 is positioned on the radiation P ₂ from the center of the optical disk 1. Since the radial / dependent adjustment can be automatically performed by the geared motor 47 of the skew adjusting mechanism 43, there is no need for manual adjustment.

In addition, since the geared motor 47 may be electrically rotationally controlled from the outside when the optical recording / reproducing apparatus is assembled and adjusted on the manufacturing line, the radial dependency adjustment work is extremely simple.

Since the radial / dependent adjustment mechanism 53 can be driven by the geared motor 47 of the skew adjustment mechanism 43, the structure can be simplified and the cost can be reduced by using one motor.

The embodiment of the present invention has been described above.
The present invention is not limited to the above embodiments, and various modifications can be made based on the technical idea of the present invention.

[0057]

The optical recording / reproducing apparatus of the present invention constructed as described above has the following effects.

According to a first aspect of the present invention, the carriage on which the optical head is mounted is slidably attached to one of the two parallel guide shafts by using a thrust bearing, and is attached to the other guide shaft. For example, a pair of rollers on both ends of a seesaw type rotary arm of a deformable radial bearing rotatably attached to a carriage are pressed by the rotation urging means of the rotary arm to the upper and lower sides of the other guide shaft. Since the play of the carriage in the horizontal and vertical directions is eliminated by the thrust bearing and the deformed radial bearing, the carriage can be smoothly moved linearly along the two guide shafts. It is possible to position with high accuracy in both horizontal and vertical directions.

According to the first aspect, the two guide shafts can be fixed to the chassis, and the carriage is slidably mounted on the two guide shafts by the thrust bearing and the modified radial bearing. And the assembly man-hours are shown in Figure 1.
Compared with the conventional optical head moving mechanism shown in FIG. 2, the number can be greatly reduced, the structure is simple, the manufacturing is easy, and the cost can be largely reduced.

According to the present invention, when the carriage is positioned in the horizontal and vertical directions with respect to the two guide shafts by the thrust bearing and the modified radial bearing, the modified radial bearing has a vertical positioning mechanism. In addition, since the horizontal positioning function is not provided, when the carriage is linearly moved along the two guide shafts, a large load is not applied to the pair of upper and lower rollers of the thrust bearing and the deformed radial bearing. Therefore, the linear drive of the carriage can be smoothly performed, and wear on the contact surface between the pair of upper and lower rollers of the deformed radial bearing and the guide shaft is reduced,
The durability can be improved. Then, the driving torque of the linear motor that drives the carriage can be reduced, and the overall size and weight of the optical recording / reproducing apparatus can be promoted as the linear motor becomes smaller and lighter.

According to a second aspect of the present invention, since the distance from the center of rotation of the rotary arm of the deformed radial bearing to the center of rotation of the pair of rollers is made equal, a pair of upper and lower rollers are crimped to both upper and lower sides of the guide shaft. At this point, the rotation center of the rotary arm is automatically positioned on the horizontal reference plane that connects the centers of the two guide shafts, and the vertical mounting accuracy of the carriage with respect to the two guide shafts is improved. Can be set.

According to the first aspect of the present invention, the rattling of the carriage with respect to the two guide shafts in the horizontal direction and the vertical direction can be eliminated. Therefore, the upper and lower recording surfaces of the optical disk having the upper and lower surfaces as the recording surfaces can be simultaneously formed. In an optical recording / reproducing apparatus for recording / reproducing, as in claim 3, an optical head moving mechanism having the same structure including an optical head, a carriage, two guide shafts, a linear motor, a thrust bearing and a modified radial bearing is provided on an optical disc. The upper and lower optical heads can be arranged symmetrically, and the upper and lower optical heads can simultaneously record and reproduce the upper and lower recording surfaces of the optical disk, and the cost can be reduced by sharing the parts.

[Brief description of drawings]

FIG. 1 is an exploded perspective view illustrating a main part of an embodiment of an optical recording / reproducing apparatus of the present invention.

FIG. 2 is an exploded perspective view of a modified radial bearing portion in the optical head moving mechanism in the above embodiment.

FIG. 3 is a side view of a modified radial bearing portion shown in FIG.

FIG. 4 is a partially cutaway side view taken along the line AA of FIG.

FIG. 5 is a side view showing an optical recording / reproducing apparatus in which the optical head moving mechanism in the above-mentioned embodiment is symmetrically arranged above and below an optical disc.

FIG. 6 is an exploded perspective view illustrating a skew adjusting mechanism and a radial dependency adjusting mechanism in the above-described embodiment.

FIG. 7 is a schematic view of the skew adjusting mechanism and the radial
It is a partially cutaway plan view of a dependency adjusting mechanism.

8 is a partially cutaway side view taken along the line BB of FIG. 7. FIG.

FIG. 9 is a block diagram showing a control circuit of a geared motor of the above skew adjusting mechanism.

FIG. 10 is a plan view and a partially cut-away side view showing an outline of the entire optical recording / reproducing apparatus of the present invention.

11A and 11B are a plan view and a partially cut-away side view illustrating a basic optical head moving mechanism in a conventional optical recording / reproducing apparatus.

FIG. 12 is a plan view and a partially cutaway side view illustrating an improved optical head moving mechanism in a conventional optical recording / reproducing apparatus.

[Explanation of symbols]

 1 Optical Disc 2 Optical Head 4 Carriage 21 Optical Head Moving Mechanism 22 Optical Head Mounting Base 24 Spindle Motor 25, 26 Guide Axis 27 Linear Motor 34 Thrust Bearing 35 Deformed Radial Bearing 36 Rotation Center Axis 37 Rotating Arm 39 Roller 40 Tension Coil Spring (with Rotation) Means)

Claims (3)

[Claims] 1. An optical disk which is rotationally driven by a spindle motor, an optical head which optically records and reproduces information on the optical disk, and the optical head which is mounted in parallel with the optical disk.
And a carriage that is linearly moved along two guide axes parallel to the radiation from the center of the optical disc, a linear motor that linearly drives the carriage along the two guide axes, and a movement of the carriage. A thrust bearing mounted on one end side in a direction perpendicular to the direction and slid along the outer circumference of the one guide shaft, and mounted on the other end side in a direction perpendicular to the moving direction of the carriage. And a deformed radial bearing that is rolled along the other guide shaft, and the deformed radial bearing is a seesaw-type rotating arm rotatably attached to the carriage via a rotation center shaft, A pair of rollers rotatably attached to both ends of the rotary arm and a pair of rollers on the other guide shaft by urging the rotary arm to rotate in one direction. An optical recording / reproducing apparatus comprising: a rotation urging unit that is pressed against both sides of the lower side. 2. The optical recording / reproducing apparatus according to claim 1, wherein the distance from the center of rotation of the rotary arm of the modified radial bearing to the center of rotation of the pair of rollers is equal. 3. The optical head according to claim 1 or 2,
An optical recording / reproducing apparatus characterized in that a carriage, two guide shafts, a linear motor, a thrust bearing, and a modified radial bearing are symmetrically arranged above and below an optical disc.