JP2000076696A - Optical disk device and its use method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent dust and dirt from sticking at a non-operation time by providing a shutter lever turnably provided around a base end part and having an objective lens closable shutter part on its tip part, closing the objective lens when an optical pickup exists on a stop position not emitting a laser beam and opening the objective lens when the optical pickup exists on the position emitting it. SOLUTION: The shutter lever 32 is formed to a shape linking a chevron part and a circular arc part, and a cum groove 32b is formed linearly on the circular arc part side of the chevron part. A cum pin 54 erected on a thread gear 48 is fitted to the cum groove 32b to form a cum mechanism, and the shutter lever 32 is rocked around an axial part 32c by the rotation of the thread gear 48 through the cum mechanism. When the objective lens 14 of the optical pickup 12 is moved from the position (a0) to the position (a1), and the cum pin 54 is rotated by an angle (θ), the shutter lever 32 is turned counterclockwise around the axial part 32c to open the objective lens 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk apparatus for reading and writing information by emitting laser light to an optical disk such as a CD (compact disk) and a method of using the same.

[0002]

2. Description of the Related Art Like a conventional optical disk device such as a CD player, an optical disk such as a CD is irradiated with a laser beam to read (reproduce) information recorded on the optical disk or to write information on the optical disk. An optical pickup for irradiating a laser beam on an optical disk is used in an optical disk device that writes (records) the optical disk.

[0003] Such an optical pickup has an objective lens for narrowing the laser light to be irradiated as described above to a beam spot of a desired size and emitting the same. However, if dust or dust adheres to such an objective lens, an error may occur in reading the information on the optical disc and a malfunction may occur.In the worst case, it may be impossible to read or write the information on the optical disc. is there.

For this reason, conventionally, for example, FIGS.
There has been an optical disk apparatus using a dustproof mechanism of an optical pickup as shown in FIG. 14, an optical pickup 12 is provided on the right side of a turntable 10 for chucking an optical disk (not shown) so as to be movable in the left-right direction in the figure, that is, in the radial direction of the optical disk.

[0005] The optical pickup 12 is provided with an objective lens 14 at a window for emitting a laser beam. The objective lens 14 can be opened and closed by a shutter plate 16. That is, the shutter plate 16 is rotatably provided around the fulcrum pin 18, and when the optical pickup 12 moves in the area where the objective lens 14 emits laser light, the shutter plate 16 is pulled by the coil spring 20. Then, as shown in FIG.
The shutter plate 16 rotates in a direction to open the objective lens 14.

A claw portion 22 is provided at an end of the shutter plate 16 fitted to the fulcrum pin 18, and an optical pickup 12 is provided on a stationary member near the turntable 10 as shown in FIG. When the laser beam is moved to the side of the turntable 10 and the emission of the laser beam is stopped, the nail 22 is brought into contact with the nail 22 and the coil spring 20 is moved.
A stopper 24 is provided which is turned to oppose the above.

For this reason, when the optical pickup 12 completes the reading or writing operation of the information emitting the laser beam and the optical pickup 12 moves to the turntable 10 side, the claw portion 22 comes into contact with the stopper 24. By rotating the shutter plate 16 in the direction indicated by the arrow in FIG. 15, the entire shutter plate 16 rotates in the same direction, and the front end thereof can close the objective lens 14.

As described above, when the optical pickup 12 finishes reading or writing information and stops at the position most moved to the turntable 10 side,
The objective lens 14 is closed by the distal end of the shutter plate 16, and the objective lens 14 can be protected from dust and dirt.

[0009]

However, in such a conventional optical disk device, a component for closing the objective lens 14 of the optical pickup 12 is provided as follows.
Shutter plate 16, fulcrum pin 18, coil spring 2
Since five parts, namely, 0, the claw 22 and the stopper 24, are required, there is a problem that the number of parts is increased and the cost of parts and the cost of assembly are increased. Further, since the position of the stopper 24 and the position of the claw portion 22 of the shutter plate 16 are strictly required to be adjusted relative to each other, strict adjustment work is required. .

[0010] Further, as another conventional example of the above-mentioned conventional example,
JP-A-10-49895 and JP-A-63-255839
Some are published in each gazette of the issue. However, the one disclosed in the former publication has a very complicated structure and a large number of parts, and thus has the problem that the cost of parts and the cost of assembly also increase as in the above conventional example.

[0011] Also, the latter published in the above publication is
Again, the large number of parts not only raises the cost of parts and assembly costs, but also causes the shutter to slide smoothly over the ridges of the cam, so that the shutter is lower than both ends of the ridges of the cam. Part must be established,
Since the optical head (optical pickup) has to be moved extra by the lower part, the moving distance of the optical head is increased, which causes a problem that the optical disk apparatus becomes larger and the operation is delayed. Also have.

In view of the above problems, the present invention is to prevent dust and dirt from adhering to an objective lens of an optical pickup and to prevent the cost of parts and assembly from rising. It is an object of the present invention to provide an optical disk device and a method of using the same.

[0013]

In order to solve the above-mentioned problems, an optical disk apparatus according to the present invention is provided with a window for emitting laser light, which is movable in a radial direction of an optical disk chucked on a turntable. In an optical disc apparatus including an optical pickup having an objective lens and a drive mechanism for driving the optical pickup via a gear, a distal end portion is provided rotatably around a base end portion supported by a stationary portion. A shutter lever having a shutter portion capable of closing the objective lens, and a shutter lever is provided between the gear and the shutter lever, and when the optical pickup comes to a stop position where no laser light is emitted, the shutter portion is the objective lens. When the lens is closed and the optical pickup moves to a position for emitting laser light, the shutter unit Wherein the shutter lever to open the objective lens is obtained by a structure and a cam mechanism for rotating.

According to the optical disk device having such a configuration, when the cam mechanism comes to the stop position where the optical pickup does not emit laser light, the shutter section closes the objective lens and the optical pickup emits laser light. When the optical pickup is moved, the shutter lever is rotated so that the shutter unit opens the objective lens. Therefore, it is possible to prevent dust or dust from adhering to the objective lens when the optical pickup is not operating.

[0015]

Embodiments of the present invention will be specifically described below with reference to the drawings. 1 to 8
FIG. 1 is a diagram referred to for describing a first embodiment of an optical disc device and a method of using the same according to the present invention.

FIG. 1 to FIG. 4 are views showing an optical disk device according to a first embodiment of the present invention. As shown in FIG. 2, on the right side of the turntable 10 for chucking the optical disk 30 (see FIG. 4), an optical pickup 12 is provided movably in the left-right direction in the figure, that is, in the radial direction of the optical disk.

The optical pickup 12 is provided with an objective lens 14 at a window for emitting laser light. The objective lens 14 can be opened and closed by a shutter portion 32 a at the tip of a shutter lever 32.
The turntable 10 and the optical pickup 12 are provided on a chassis plate 34 so as to rotate or reciprocate.

Also, as shown in FIG.
A spindle motor 36 for driving the spindle 10a of the turntable 10 and a thread motor 38 for driving the reciprocating movement of the optical pickup 12 are provided below.

The output shaft of the thread motor 38 is provided with a motor gear 42 on the chassis plate 34. The motor gear 42 has an intermediate gear 4 having a larger diameter.
4 are engaged. An intermediate gear 46 having a smaller diameter than the intermediate gear 44 is provided integrally on the same axis of the intermediate gear 44, and a thread gear 48 having a larger diameter meshes with the intermediate gear 46. A drive gear 50 having a smaller diameter than the thread gear 48 is provided integrally on the same axis as the thread gear 48, and rack teeth 40 formed on the base side of the optical pickup 12 mesh with the drive gear 50. ing.

Accordingly, the sled motor 38, the motor gear 42, the intermediate gears 44 and 46, the sled gear 48, and the drive gear 50 constitute a drive mechanism for driving the optical pickup 12 as a whole. As shown in FIG. 4, the optical pickup 12 can reciprocate along a main shaft 52 and a sub shaft 55 provided on the chassis plate 34 via a bearing.

In FIG. 3, a shaft portion 32c is integrally formed at the right end of the shutter lever 32 in the figure, and the shaft portion 32c is rotatably supported by the chassis plate 34 via a bearing 58 (shaft). Support). Shutter lever 3
As shown in FIG. 2, reference numeral 2 denotes a shape formed by connecting a right-angled portion on the right side of the figure to an arc-shaped portion on the left side of the figure. Is formed with a cam groove 32b.

The cam groove 32b of the shutter lever 32
A cam mechanism is formed by fitting a cam pin 54 erected on the thread gear 48 into the thread gear 48.
With the rotation of the shutter lever 32, the shutter lever 32 swings around the shaft portion 32c as a fulcrum via the cam mechanism.

The operation of such an optical disk device will be described below. As shown in FIG. 5, when the objective lens 14 of the optical pickup 12 moves from the position a ₀ to the position a ₁ and the cam pin 54 rotates by an angle θ from the broken line position to the solid line position, the shutter lever 32 By the rotation of the cam pin 54 fitted in the cam groove 32b, the cam pin 54 rotates counterclockwise about the shaft portion 32c as a fulcrum. For this reason, the shutter portion 32a of the shutter lever 32 is
The optical pickup 12 moves downward from the position of the objective lens 14 in the figure to open the objective lens 14. Incidentally, the angle θ can be about 43.669 °.

As described above, with the objective lens 14 opened at the position a ₁ , the optical pickup 12
As shown in the table, TOC (table of conte
It is possible to start reading in the reading section T of nts and the table of contents of information. As shown in FIG. 6, when the optical pickup 12 reads information from the optical disc 30 and the objective lens 14 moves from the position a ₀ to the position a ₃ (the position when the thread gear 48 makes one rotation), as shown in FIG. when the cam pin 54 is returned to its original position, but also the shutter portion 32a of the shutter lever 32 returns to the original position, since this time is the objective lens 14 has moved to a position a ₃ differ from the original position a _0, Shutter section 32 of shutter lever 32
The objective lens 14 is not closed by a.

In this manner, after the thread gear 48 makes one rotation, the same operation is repeated and the optical pickup 12 is rotated.
Can move further outside the radius of the optical disc 30 to perform information reading and writing operations.

The thread gear 48 is a thread motor 38
When the optical pickup 12 moves in the opposite direction to the above, that is, inward of the radius of the optical disc 30, even if the shutter lever 32 swings during the operation of the optical pickup 12, the shutter portion 32a can be rotated by the object. Only when the operation of the optical pickup 12 is completed and the optical pickup 12 stops at the position closest to the turntable 10 without closing the lens 14, the shutter portion 32 a swings the shutter portion 32 a so that the objective of the shutter portion 32 a becomes the objective. Lens 14 can be closed.

In FIG. 7, for example, a position a _{0 in} the radial direction of the optical disk 30 is 21.9 mm from the center position C of the turntable 10, and a position a ₁ is 2 from the center position C.
3.5 mm, position a ₂ is 24.5 mm from center position C,
Position a ₃ shows the position of 13.19mm from the position a _0, in particular between positions a ₁ and a ₂ are formatted TOC reading period T, radially outward of the position a ₂ (right in FIG. The information content is formatted in (1).

As shown in FIG. 8, an inclined surface 12a is formed in the upper right portion of the optical pickup 12 in the figure, so that the shutter portion 32a of the shutter lever 32 is guided by the inclined surface 12a, so that the optical pickup can be smoothly moved. 12 and can stop.

In FIG. 8, for example, the dimension B between the chassis plate 34 and the optical disk 30 is 19.4 mm,
The dimension C between the upper surface of the optical pickup 12 and the chassis plate 34 can be 17.1 mm, and the dimension A between the upper surface of the optical pickup 12 and the optical disk 30 can be 2.3 mm. The thickness of the shutter portion 32a of the shutter lever 32 can be set to about 0.5 mm in practice so as not to contact the lower surface of the optical disc 30.

According to the optical disk device of the embodiment, the shutter portion 32 of the shutter lever 32
When the optical pickup 12 comes to a stop position where the optical pickup 12 does not emit laser light, the shutter 32a closes the objective lens 14, and the optical pickup 12 emits laser light. The shutter lever 3 so that the shutter 32a opens the objective lens 14
2 is rotated, so that the optical pickup 12
It is possible to prevent dust or dust from adhering to the objective lens 14 when the lens is not operating.

Since the shutter lever 32, the bearing 58, and the cam pin 54 are sufficient as components for closing the objective lens 14 of the optical pickup 12, dust and dirt adhere to the objective lens 14. In addition, it is possible to prevent soaring parts costs and assembling costs for preventing the problem.

Further, as compared with the dustproof mechanism using the conventional shutter plate, the distance between the positions a ₁ to open position a ₀ and the objective lens 14 for closing the objective lens 14 can be short, quick The operation can be realized and the positional relationship between the parts does not have to be so severe, so that an increase in assembly cost can be prevented.

FIGS. 9 and 10 are diagrams referred to for describing the second embodiment of the present invention. In the first embodiment, the shaft portion 32c is formed at the shaft support side end of the shutter lever 32, and is rotatably attached to the chassis plate 34 via the bearing 58. In the second embodiment, as shown in FIG.
The end of the shutter lever 32 on the pivot side is bent in a step shape so as to change the height, and the chassis plate 3
4 in that the shutter lever 32 is rotatably attached to the chassis plate 34 by being caulked (or melt-pressed).

After the shutter lever 32 is thus attached to the chassis plate 34, as shown in FIG. 9, the shutter lever 32 indicated by a solid line is rotated in the direction of an arrow (clockwise) to indicate a two-dot chain line. By arranging them at predetermined positions similar to those in the first embodiment, the same operation as in the first embodiment as described above can be performed, and the same effects can be obtained. it can.
Further, since the bearing 58 is not required as compared with the first embodiment, it is possible to further prevent a rise in component cost and assembly cost.

FIGS. 11 to 13 are views referred to for describing the third embodiment of the present invention. In the first embodiment, the cam groove 32b is formed on the shutter lever 32 side and the thread gear 48 is formed.
The cam pin 54 is provided on the side
The present embodiment is different from the first embodiment in that a cam pin 64 is provided on the shutter lever 62 side and a cam groove 72 is formed on the thread gear 48 side.

According to the optical disk device of the third embodiment, the cam groove 72 is formed together with the thread gear 48.
Is rotated, the shutter lever 62 swings about the pivot 62b via a cam pin 64 sliding along the cam groove 72, whereby the shutter 62a opens and closes the objective lens 14. The operation can be performed in the same manner as in the first embodiment.

In the above embodiment, a CD has been described as an example of an optical disk.
-The present invention can be applied to any other optical disks such as ROM, DVD, and CD-I.

Although the embodiments of the present invention have been specifically described above, the present invention is not limited to the above-described embodiments, and may be variously modified based on the technical idea of the present invention. Can be changed.

[0039]

As described above, according to the optical disk apparatus of the present invention, when the cam mechanism comes to the stop position where the optical pickup does not emit laser light, the shutter section closes the objective lens, and the optical pickup moves. When moving to the position where laser light is emitted, the shutter lever is rotated so that the shutter opens the objective lens, preventing dust and dust from adhering to the objective lens when the optical pickup is not operating. can do.

As the components for closing the objective lens of the optical pickup, only three components such as a shutter lever, a bearing, and a cam pin are sufficient, and thus a component for preventing dust and dirt from adhering to the objective lens. It is also possible to prevent soaring costs and assembly costs.

Also, according to the second embodiment, the bearing 58 used in the first embodiment is not required, so that the number of parts can be further reduced to prevent dust and dirt from adhering to the objective lens. It is possible to prevent soaring parts costs and assembling costs for prevention.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an optical disk device according to a first embodiment of the present invention.

FIG. 2 is a plan view of the optical disk device in FIG.

FIG. 3 is a sectional view of the optical disk device in FIG. 2;
FIG.

FIG. 4 is a sectional view of the optical disk device taken along line IV-IV in FIG. 2;

FIG. 5 is a plan view for explaining the operation of the optical disk device in FIG. 1;

FIG. 6 is a plan view for explaining the operation of the optical disk device in FIG. 1;

FIG. 7 is a diagram showing positions a _{0 to} a _{3 at} which the objective lens 14 of the optical pickup 12 moves for explaining the operation of the optical disk device in FIG. 1;

8 is an optical disk 30 of the optical disk device in FIG.
FIG. 4 is a partial cross-sectional side view for explaining a positional relationship between the optical pickup 12 and a chassis plate 34;

FIG. 9 is a plan view showing a main part of an optical disk device according to a second embodiment of the present invention.

FIG. 10 is a cross-sectional view of the shutter lever 32 of FIG. 9;
It is a line sectional view.

FIG. 11 is a perspective view of a main part of an optical disc device according to a third embodiment of the present invention.

FIG. 12 is a plan view of an optical disc device according to a third embodiment of the present invention.

13 is a partial cross-sectional side view of a main part of the optical disk device in FIG.

FIG. 14 is a plan view of an essential part showing an operation state of a conventional optical disk device.

FIG. 15 is a plan view of a main part showing another operation state of the conventional optical disk device.

[Description of Signs] 10 turntable, 10a spindle, 12 optical pickup, 12a slope, 14 objective lens, 1
6 Shutter plate, 18 Support pin, 20 Coil spring, 22 Claw portion, 24 Stopper, 30 Optical disk, 32 Shutter lever, 32a Shutter portion, 32b Cam groove, 32c Shaft portion, 34 Chassis plate, 36: spindle motor, 38: thread motor, 40: rack teeth, 42: motor gear, 44, 46
... Intermediate gear, 48 ... Thread gear, 50 ... Drive gear, 5
2 ... main shaft, 54 ... cam pin, 55 ... counter shaft, 58 ... bearing,
62: shutter lever, 62a: shutter portion, 62
b: shaft support, 64: cam pin, 72: cam groove

Claims (4)

[Claims] 1. An optical pickup which is movable in a radial direction of an optical disk chucked on a turntable and has an objective lens at a window for emitting laser light, and a drive for driving the optical pickup via a gear. A shutter lever provided rotatably about a base end pivotally supported by a stationary portion, and having a shutter at a distal end capable of closing the objective lens; and a gear. And when the optical pickup comes to a stop position where the optical pickup does not emit laser light, the shutter section closes the objective lens, and the optical pickup moves to a position where the optical pickup emits laser light. When the shutter is turned, the shutter lever is rotated so that the shutter opens the objective lens. Optical disc apparatus characterized by having a mechanism. 2. The optical disc according to claim 1, wherein the cam mechanism has a cam pin provided on the gear side, and a cam groove formed on the shutter lever side and fitted with the pin. apparatus. 3. The optical disc according to claim 1, wherein the cam mechanism has a cam pin provided on the shutter lever side and a cam groove formed on the gear side and fitted with the pin. apparatus. 4. An optical pickup which is movable in a radial direction of an optical disk chucked on a turntable and has an objective lens at a window for emitting a laser beam, and a drive for driving the optical pickup via a gear. A shutter lever provided rotatably about a base end pivotally supported by a stationary portion, and having a shutter at a distal end capable of closing the objective lens; and a gear. And an optical disc device having a cam mechanism configured between the shutter lever and the shutter lever. When the cam mechanism comes to a stop position where the optical pickup does not emit laser light, the shutter unit controls the objective lens. When the shutter is closed and the optical pickup is moved to a position for emitting laser light, the shutter unit is turned to the pair. Using an optical disk apparatus according to claim wherein it has a shutter lever to rotate so as to open the lens.