JPH054095Y2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" This invention relates to an optical pick-up head adjustment device for adjusting the direction of the optical axis of the optical pick-up head with respect to the disc in an optical disc playback device.

``Prior Art'' Generally, in an optical disk playback device, a head base on which an optical pick-up head is mounted is supported so as to be movable in the radial direction of the disk. is configured to read signals recorded on the

In this type of disk reproducing apparatus, the optical axis of the optical pick-up head must always be perpendicular to the disk surface in order to ensure that the optical pick-up head can read the signals recorded on the disk surface.

However, in conventional disk playback devices of this kind, the optical pickup head is fixedly attached to the head base, and the direction of the optical axis of the optical pickup head with respect to the disk surface cannot be changed. Therefore, in such a disc playback device, if the disc is bent or the optical pickup head is not properly installed, the optical axis may no longer be perpendicular to the disc surface. However, there have been problems such as deterioration of the signal reproducing ability or the inability to reproduce the signal.

Therefore, the applicant provided a device in Japanese Utility Model Application No. 118981/1983, which is capable of adjusting the direction of the optical axis of an optical pickup head with respect to the disk surface.

The device is shown in FIG. 8, in which reference numeral 1 is a disk mounted on a turntable (not shown), 2 is placed below the disk 1, and is oriented in the radial direction of the disk 1 (in the direction of arrows P1 and P2).
The head base is supported so that it can move towards the head.

A tilt base support portion 3 is formed at one end of the head base 2, and one end portion of a tilt base 5 is rotatably attached to the tilt base support portion 3 via a shaft portion 4. tilt base 5
is rotatable in the directions of arrows P3 and P4 about the axis of the shaft portion 4, that is, the axis that is orthogonal to the radial direction of the disk 1 and located approximately parallel to the disk 1. An optical pickup head 7 is attached to the tilt base 5 with an objective lens 6 facing the lower surface of the disk 1. Although not shown, when installing the optical pickup head 7, the amount of inclination of the optical pickup head 7 with respect to the circumferential direction of the disk 1 can be adjusted by adjusting the amount of rotation of the mounting screw. On the other hand, a grooved cam 8 is attached to the other end of the head base 2. The grooved cam 8 is formed by forming a spiral groove 9 on the circumferential surface of a cylindrical body, and is attached to the head base 2 so as to be rotatable about its axis. This grooved cam 8 is adapted to be rotated by a motor (not shown). A protrusion 10 is formed at the other end of the tilt base 5, and the protrusion 10 engages with the groove 9. Based on this configuration, when the grooved cam 8 rotates, the tilt base 5 rotates in the directions of arrows P3 and P4, thereby aligning the optical axis 11 of the optical pickup head 7 in the radial direction of the disk 1. , that is, the arrows P5 and P6 change.

In this device, for example, if the outer periphery of the disk 1 is bent due to its own weight,
The amount of this deflection is detected by a detector (not shown), and this detection output causes the motor to rotate and the grooved cam 8 to rotate by a certain amount, which causes the tilt base 5 and the optical pickup head 7 to rotate. The optical axis 11 is shifted to a position perpendicular to the radial direction of the disk 1.

"Problems to be Solved by the Invention" The problems to be solved by this invention are the following points which cannot be solved by the apparatus shown in FIG. 8 above.

That is, in the above-mentioned apparatus, adjustment of the optical axis 11 with respect to the disk 1 is possible in the radial direction of the disk 1, and adjustment in the circumferential direction of the disk 1 is also possible. However, in these adjustment configurations, the tilt base 5, which is a separate member, is arranged parallel to the head base 2 and separated from the head base 2 by a certain distance.
In addition, a rotation support mechanism and a rotation drive mechanism for the tilt base 5 are required, which makes the entire device complicated and large, and as a result, the optical pickup head drive system as a whole It becomes difficult to downsize and flatten the Particularly when trying to move the optical pick-up head over as wide a range as possible, there is a demand for making related parts other than the optical pick-up head as small and thin as possible. It was impossible to fully meet the demands.

``Means to Solve the Problem'' This idea is to read the signals recorded on the disk by the optical pickup head by moving the plate-shaped head base on which the optical pickup head is mounted in the radial direction of the disk. In a disc playback device, the disc player is configured to be elastically slightly rotatable in a direction perpendicular to the disc surface by forming a U-shaped slit and forming a substantially rectangular opening inside the slit. The second adjustment base is formed by forming a plate-like body into a predetermined shape and having an opposing wall portion and its supporting plate portion integrally connected to each other. The support plate portion of the second adjustment base is fixed to the rotation end side of the first adjustment base, and the opposing wall portion of the second adjustment base is positioned within the opening of the first adjustment base, and these opposing wall portions are In between, the optical pick-up head is attached so as to be rotatable about a rotation axis that is perpendicular to the virtual rotation axis of the first adjustment base and substantially parallel to the disk surface, and the optical axis of the optical pick-up head is aligned with the disk diameter. It is configured so that it can be slightly rotated in both the direction and the circumferential direction of the disk.

``Example'' Below, an example of this invention is shown in Figures 1 to 7.
This will be explained with reference to the figures.

FIGS. 4 to 7 are diagrams showing the construction of the main parts of a disc playback device equipped with an optical pickup head adjusting device according to the invention. In these figures, numeral 21 is a chassis, and this chassis 2
A disk drive motor 22 is attached to the central lower surface of 1. A rotating shaft 23 of the motor 22 projects upward from the upper surface of the chassis 21, and a turntable 24 is fixed to the upper end thereof. Further, on the upper surface of the chassis 21, arrows P7,
The head device 26 is supported so as to be movable in the P8 direction. The head device 26 reads signals from a disk 27 mounted on the turntable 24, and details of its structure and mounting state will be described later.

Side plate parts 28, 28 projecting upward are formed on both left and right sides of the chassis 21, and a tray holder 29 is supported between these side plate parts 28, 28 so as to be positioned in front of the turntable 24.
The tray holder 29 is a rectangular plate-shaped body, and guide members 3 are provided on both left and right sides of the tray holder 29 extending in the front and back direction.
0 and 30 are fixed. The guide member 30 is
It has a protrusion 31 and guide pins 32, 32. The guide pins 32, 32 of the left and right guide members 30, 30 are connected to the side plate portions 28, 28, respectively.
Elongated holes 33, 33 extending in the vertical direction formed in
...It is inserted inside. With this configuration, the tray holder 29 is vertically movable within the range in which the guide pin 32 is guided by the elongated hole 33.

The guide members 30, 30 include a disk 27.
Tray 3 that transports the data from the eject position to the playback position and vice versa.
4 is installed. The tray 34 is a substantially rectangular plate-like body, and has a disk mounting portion 35 formed on its upper surface, and guide grooves 36, 36 formed on both left and right sides. This tray 34 has a guide groove 36,
The loading motor 3 is attached to the guide members 30, 30 by fitting the protrusions 31, 36 onto the tray holder 29.
7 and the driving force transmission mechanism 38, the arrow P7,
It is designed to be moved in the P8 direction.

Further, a clamper 39 for holding the disk 27 on the turntable 24 is attached to the guide members 30, 30. The clamper 39 is
A disc stabilizer 41 is rotatably attached to a holding plate 40, and the stabilizer 41 holds the disc 27 on the turntable 24 when the entire disc is lowered.

On the outside of the side plate parts 28, 28 of the chassis 21,
Slide plates 42, 42 are provided. The slide plate 42 has cam holes 43, 43 formed therein.
It is arranged on the outside of the side plate part 28 with the tips of the guide pins 32, 32 inserted therein,
Washers 44 are attached to the tip surfaces of the guide pins 32,
44 is attached with screws 45, 45 to prevent it from falling outward. The slide plates 28, 28 are moved in the directions of arrows P7, P8 by an elevation motor 46 and a driving force transmission mechanism 47 attached to the chassis 21. Based on this configuration, when the motor 46 rotates, the slide plates 42, 42
moves in the directions of arrows P7 and P8 to open the cam holes 43 and 4.
3... The guide pins 32, 32... are guided along the guide pins 32, 32... to move the guide members 30, 30 upward or downward.
The members fixed and supported at 0 and 30, that is, the tray holder 29, the tray 34, and the clamper 39, move upward or downward integrally.

To explain the structure and mounting state of the head device 26, first, guide rod mounting portions 48, 48, 49, and 49 are formed on the upper surface of the chassis 21 at the front end and rear end of the opening 25, respectively. Guide rods 50, 50 are attached between the guide rod attachment parts 48, 48, 49, 49, respectively. A head base 51 is attached to the guide rods 50, 50.
are mounted so as to be movable in the directions of arrows P7 and P8 (radial direction of the disc 27 mounted on the turntable 24) via guide portions 52, 52, . . . fixed thereto. The head base 51 is moved in the above direction by a feed motor 53 and a driving force transmission mechanism 54 attached to the chassis 21. An optical pickup head 56 is attached to the head base 51 via a tilt base 55 (second adjustment base).

The head base 51, tilt base 55, and optical pickup head 56 constitute a head device 26, and details of this head device 26 are shown in FIGS. 1 through 4. The head base 51 is made by cutting a thin elastic steel plate into a predetermined shape by press forming or the like. It is starting to move in the direction of The head base 51 has a U-shaped slit 57 in its center and a substantially rectangular opening 58 inside the slit 57 by press molding or the like. slit 57
The U-shaped portion between the opening 58 and the opening 58 constitutes a first adjustment base 59, and this adjustment base 59 is centered around the hinge-like connecting portions 61, 61 with the base 60, that is, the connecting portion 61 , 61, which is perpendicular to the radial direction of the disk 27 and substantially parallel to the disk 27.
2 in the directions of arrows P9 and P10 (the disk 27 mounted on the turntable 24)
(direction perpendicular to the plane).

The tilt base 55 is formed by press-molding a metal plate into a predetermined shape, and the upper part is connected to the connecting plate part 6.
A supporting plate portion 65 that projects laterally is integrally formed on the lower side of one wall portion of opposing wall portions 64, 64 connected at 3. This tilt base 55 has opposing wall portions 64, 64 at an opening 58.
The support plate portion 65 is positioned at the center of the rotating end portion 66 of the adjustment base 59 and on the lower surface side of the rear end of the base portion 60, and the base end portion of the support plate portion 65 is positioned within the spacer 67. It is fixed to the adjustment base 59 by screws 68 via the screws 68. In addition, the support plate portion 65
A screw 70 is rotatably inserted into a hole 69 formed at the tip of the head, and the upper end of the screw 70 is screwed into the base 60 of the head base 51. screw 70
A coil spring 71 is wound around the base portion 60 and the support plate portion 65 to bias the base portion 60 and the support plate portion 65 in a direction in which they are separated from each other. Based on this configuration, when the screw 70 is rotated to move the support plate portion 65 toward and away from the base portion 60, the adjustment base 59 moves in the directions of arrows P9 and P10 about the virtual rotation axis 62. do.

The optical pickup head 56 includes a holding tube 74 (lens tube) in which an objective lens 73 is mounted at the upper end of a body 72 in which a signal detection section and the like are built-in. A support wall portion 75 is formed in the body 72 and projects laterally.
A hole 77 having a stepped portion 76 is formed in one side of the hole 5 . This optical pick-up head 56 is installed with one side of the support wall 75 in which the hole 77 is formed positioned below one side of the adjustment base 59.
The front and rear ends of the support wall 75 are rotatably attached to the opposing walls 64, 64 of the tilt base 55 via shafts 78, 78. At this time, the opposing wall 6
4 and 64 are in substantially close contact with the front and rear support walls 75 of the optical pickup head 56, respectively, and almost no unnecessary external protrusion occurs in this direction, that is, in the direction of movement of the optical pickup head 56. Based on this configuration, the optical pickup head 56
are arrows P11, 12 centered on the shaft bodies 78, 78.
It can be rotated freely in the direction. Here, the shaft bodies 78, 78
The rotational axis 79 of the optical pickup head 56 passing through
is perpendicular to the virtual rotation axis 62, is located parallel to the disk 27 mounted on the turntable 24, and extends in the direction of movement of the head base 51. In addition, the screws 68 and 70, the objective lens 7
3 are located on the rotation axis 79. A screw 80 is rotatably inserted into the hole 77 of the support wall 75, and the upper end of the screw 80 is screwed onto the adjustment base 59. Between the stepped portion 76 of the hole 77 and the adjustment base 59, the adjustment base 59 and the support wall portion 75 are connected with the screw 80 wound thereon.
A coil spring 81 is interposed to bias the two in the direction of separating them from each other. In this configuration, when the screw 80 is rotated to move the support wall portion 75 toward and away from the adjustment base 59, the optical pickup head 56 rotates about the rotation axis 79 in the directions of arrows P11 and P12. do. In addition, Figure 2,
In FIG. 3, reference numeral 82 is the optical axis of the optical pickup head 56. In FIG.

To play a disc using this disk playback device, first give the device a command to eject the tray 34 and turn on the motor 37 to remove the tray 34.
is moved in the direction of arrow P8, and the tray 34 is pulled out to a position where the disk mounting portion 35 is exposed to the outside of the outer case of the apparatus. Here, the disk 27 is placed on the disk placement section 35. Then, a command to close the tray 34 is given to the device, and the motor 37 is reversed to move the tray 34 in the direction of arrow P8. When the tray 34 moves in the above direction and the center of the disk 27 matches the center of the turntable 24,
While the rotation of the motor 37 is stopped, the motor 46 is turned on and the slide plates 42, 42 move in the direction of arrow P7, whereby the guide pins 32, 32, . . . of the guide members 30, 30, which are in the raised position, The members that are guided by the cam holes 43, 43 and are thus supported and fixed to the guide members 30, 30, namely the tray holder 29, the tray 34, and the disk 2
7. The clamper 39 descends. Disk 27 is
While the tray 34 is descending, the turntable 2
4 and placed on the same turntable 24. Further, the disk 27 is rotatably held on the turntable 24 by a stabilizer 41 of a clamper 39 that is lowered. In this state, the motor 46 stops rotating. When a disk reproduction command is given to the device, the motor 22 is turned on and the disk 27 rotates together with the turntable 24 and the stabilizer 41. At the same time, the motor 53 is turned on and the head device 26 is moved in the direction of arrow P7 by a predetermined amount, and the optical pickup head 56 reads the signal recorded on the signal recording surface of the disk 27. Regeneration takes place.

By the way, when playing the above disc,
In order to accurately reproduce the disc 27, the optical axis 82 of the optical pickup head 56 must be perpendicular to the disc surface. However, in this lever device, the optical axis 82 relative to the disk surface
It is possible to adjust the direction of the disc in the radial direction and the circumferential direction of the disc, and it is possible to accurately reproduce the disc.

That is, in this device, the direction of the optical axis 82 of the optical pickup head 56 can be adjusted by operating the head device 26 in the following manner.

First, with reference to FIG. 2, a method for adjusting the direction of the optical axis 82 with respect to the radial direction of the disk 27 will be described. To make this adjustment, the screw 70 is rotated to move the support plate portion 65 of the tilt base 55 toward and away from the base portion 60 of the head base 51. In this way, the adjustment base 59 fixed to the support plate part 65 via the screw 68 rotates in the directions of arrows P9 and P10 about the virtual rotation axis 62, and is fixed to the adjustment base 59. The head base 51 and the optical pickup head 56 supported by the head base 51 rotate in the same direction. When the optical pick-up head 56 is rotated in the above direction, its optical axis 82 is aligned with the arrow P13,
Rotates in the P14 direction, thereby disc 27
The direction of the optical axis 82 with respect to the radial direction changes. Therefore, by appropriately rotating the screw 70, the support plate portion 65
By adjusting the position of the optical axis 82, the optical axis 82 can be made perpendicular to the signal recording surface of the disk 27 in its radial direction.

Further, referring to FIG. 3, a method for adjusting the direction of the optical axis 82 with respect to the circumferential direction of the disk 27 will be explained. To perform this adjustment, the screw 80 is rotated to rotate the optical pickup head 56. Axis line 7
9 in the directions of arrows P11 and P12. In this way, the optical axis 82 of the optical pickup head 56 rotates in the directions of arrows P15 and P16, thereby changing the direction of the optical axis 82 with respect to the circumferential direction of the disk 27. Therefore, screw 8
0 to adjust the position of the optical pickup head 56 in the directions of arrows P11 and P12, the optical axis 82 can be made perpendicular to the signal recording surface of the disk 27 in its circumferential direction.

As mentioned above, with this disc playback device,
Since the direction of the optical axis 82 of the optical pick-up head 56 can be adjusted in the radial direction and circumferential direction of the disk 27, the optical axis 82 can be accurately orthogonal to the signal recording surface of the disk 27. The disc 27 can be played back accurately.

Further, as is clear from FIGS. 2 and 3, this adjustment device can be formed extremely compactly with respect to the optical pickup head 56, realizing miniaturization and planarization as a whole. For example, the tilt base 55 increases only by approximately the thickness of the wall portion 64 of the optical pickup head 56 in the front-rear direction, and in the vertical direction as well, except for the portion where the support plate portion 65 is present, the tilt base 55 only increases in thickness. A plate thickness of approximately 51 mm is sufficient. Such a configuration is extremely effective when, for example, it is desired to increase the movement range of the optical pickup head 56 as much as possible. In other words, when considering the range of movement of the head, the constraints are the turntable, clamper, etc. located near the center of the disk, and the disk drive motor located below it. Accordingly, by arranging the support plate portion on the outer peripheral side of the disk, the optical pickup head 56 can be brought as close as possible to the center position of the disk, as shown in FIGS. 4 and 5.

Furthermore, this adjustment device has an extremely simple component structure consisting of a head base 51, which is a single press-molded part with an integrally punched elastic hinge-shaped part, and a tilt base 55, which is also a single sheet metal press-molded part. Moreover, the mounting structure is naturally extremely simple, and the cost advantage is also very large.

``Effect of the invention'' According to this invention, the optical axis of the optical pick-up head is configured to be able to rotate slightly in the radial direction of the disk and in the circumferential direction of the disk. and in the circumferential direction, the static position of the optical axis can be easily adjusted, and the optical axis can be accurately orthogonal to the disk surface, allowing accurate disk playback. In addition, the component parts can be produced extremely easily and at low cost, the mounting structure is simple, and the entire device can be made smaller and flat. It has many effects, such as being able to fully satisfy even the most demanding demands.

[Brief explanation of the drawing]

1 to 7 are diagrams for explaining one embodiment of this invention, in which FIG. 1 is a plan view of the head device portion of a disk playback device to which this invention is applied, and FIG. - A side view in line, FIG. 3 is a front view in line from FIG. 1, FIG. 7 is a front sectional view of the same, FIG. 7 is a side view taken from the line of FIG. 4, and FIG. 8 is a side view of a conventional optical pickup head adjusting device. 27...Disk, 51...Head base, 5
5...Second adjustment base (tilt base), 56...
...Light pick up head, 57...Slit, 5
9...First adjustment base, 62...Virtual rotation axis,
64... Opposing wall part, 65... Support plate part, 79...
Rotation axis line, 82...optical axis.

Claims (1)

[Scope of utility model registration request] It has a plate-shaped head base that is movably supported in the radial direction of the disk to be loaded, and an optical pick-up head mounted on the head base. In a disc playback device designed to read signals recorded on the disc surface, a U-shaped slit is formed and a roughly rectangular opening is formed inside the slit, so that the signal can be played elastically in the direction perpendicular to the disc surface. It includes a first adjustment base that is configured to be slightly rotatable, and a second adjustment base that is formed by forming a plate-like body into a predetermined shape and that includes an opposing wall portion and its support plate portion that are integrally connected. The support plate portion of the second adjustment base is fixed to the rotation end side of the first adjustment base, and the opposing wall portion of the second adjustment base is positioned within the opening of the first adjustment base. between these opposing wall portions, perpendicular to the virtual rotation axis of the first adjustment base;
The optical pick-up head is mounted so as to be rotatable about a rotational axis substantially parallel to the disk surface, and the optical axis of the optical pick-up head is configured to be slightly rotatable in the radial direction of the disk and in the circumferential direction of the disk. An optical pickup head adjustment device for a disc playback device, characterized in that: