JPH07129969A - Driving mechanism for optical pickup device - Google Patents

Abstract

PURPOSE:To simplify a structure and to improve reliability by surely preventing a lock phenomenon occurring between a feeding spring member and a feeding screw member and eliminating a position detection switch. CONSTITUTION:An optical pickup device 20 is driven reciprocally on a radius of a recording medium 5 by the feeding screw member 24 rotated by a driving motor 23 and forming a feeding screw 24A on the outer peripheral part and the feeding spring member 25 forming an engage projecting part 25A engaging with the feeding screw 24A. A feeding spring member deviation stopper 36 controlling the deviation amount of the feeding spring member 25 is provided on the pedestal 22 of the optical pickup device 20 for holding an engaging state between the engage projecting part 25A and the feeding screw 24A. The feeding screw member 24 is provided with an incomplete screw part 29 where the engage projecting part 25A is placed correspondedly in the state where the optical pickup device 20 is moved to the outermost peripheral position or the innermost peripheral position of the recording medium 5. The incomplete screw part 29 is made so that the feeding screw 24A is got over by the engage projecting part 25A without being controlled by the feeding spring member deviation stopper 36.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention irradiates a disc-shaped optical recording medium, that is, an optical disc, a magneto-optical disc or the like (hereinafter collectively referred to as an optical disc) with a laser beam to record in a recording area of the recording medium. An optical pickup device of an optical disc device for recording or recording a recorded information signal,
More specifically, the present invention relates to a drive mechanism of an optical pickup device that reciprocally drives the optical pickup device in the radial direction of a recording medium.

[0002]

2. Description of the Related Art An information signal is recorded or recorded in the recording area of an optical disk in which a spiral or concentric recording area is formed from the inner circumference to the outer circumference on the surface of a disk substrate molded of polycarbonate or the like. An optical disk device that reproduces an information signal is generally equipped with a rotary drive device that holds an optical disk and rotationally drives it at a constant linear velocity, a laser beam light source, an objective lens or a photodetector, and the like. Consists of an optical pickup device that focuses the laser beam onto the recording area of the optical disk and focuses the reflected laser beam again through the objective lens to detect with a detector, or a magnetic head device that applies an external magnetic field to the recording area. Has been done.

A conventional reproduction type optical disc apparatus 1 is constructed as shown in FIG. 7, and an optical disc 5 is detachably mounted on a disc table 3 which is driven to rotate by a spindle motor 2 by a chucking magnet 4. To be done. The optical disc 5 has a recording area in which an information signal is recorded from the inner circumference to the outer circumference, and the optical pickup device 10 reproduces the information signal. The spindle motor 2 is controlled by the motor control circuit 7 whose operation is controlled by the system controller 6 according to the position of the recording area of the optical disc 5 scanned by the optical pickup 11 of the optical pickup device 10 so that the linear velocity of the optical disc 5 becomes constant. Driven to.

As will be described later, the optical pickup device 1
The information signal recorded in the recording area of the optical disk 5 which is optically read by the optical pickup 11 of 0 is sent to a processing system (not shown) via the reproduction processing unit 8 including a reproduction amplifier and a comparator signal processing circuit. It The optical pickup device 10 is a base 1 made of aluminum die cast.
2, the optical pickup 11 and other constituent members are assembled, and the optical pickup 5 is supported by a feed screw member 14 which is rotationally driven by a drive motor 13 and a guide member (not shown), and is reciprocally driven on the radius of the optical disk 5. . The drive motor 13 is controlled by a motor control circuit 7 whose operation is controlled by the system controller 6.

In addition, the optical pickup device 10 has a focus / focus controller whose operation is controlled by the system controller 6.
The tracking control circuit 9 is configured to move the objective lens in the focus control direction and the tracking control direction via the biaxial device. The optical pickup device 10 irradiates the optical disc 5 with a laser beam from the optical pickup 11 to detect reflected light based on the information signal formed in the recording area, and sends the output to the reproduction processing section 8.

By the way, the optical pickup device 10 is
The feed screw member 14 and a guide shaft member (not shown) hold the optical disc 5 horizontally under the optical disc 5, and cooperate with the feed screw member 14 to reciprocate the optical pickup device 10 on the radius of the optical disc 5. The feed spring member 15 is provided for the purpose. One end of the feed spring member 15 formed of a spring plate member is cantilevered and fixed by the base 12, and the free end side is bent in a substantially V-shape to form a feed screw formed on the outer periphery of the feed screw member 14. An engagement protrusion 15A that meshes with the screw 14A is formed.

The feed screw member 14 formed by threading the feed screw 14A on the outer peripheral portion of the round bar member is integrally formed with a transmission gear 14B which meshes with the output gear 13A of the drive motor 13 at one end. The drive motor 13 whose operation is controlled by the motor control circuit 7 is rotationally driven to be rotationally driven. As the feed screw member 14 rotates, the optical pickup device 10 moves to the engaging protrusion 15
A is moved along the axial direction of the feed screw member 14 via the feed spring member 15 meshed with the feed screw 14A formed on the outer peripheral portion. For example, when the optical pickup device 10 is moved from the outer peripheral portion of the optical disk 5 to the inner peripheral side and the optical pick-up 11 reaches the innermost peripheral position of the recording area, the optical pickup device 10 collides with a stopper (not shown). Immediately before being locked, for example, the switch operating portion formed on the base 12 operates the inner peripheral portion detection switch 16A. The output of the inner peripheral portion detection switch 16A is sent to the system controller 6 to control the operation of the motor control circuit 7, and the drive motor 13 is stopped.

On the other hand, when the optical pickup device 10 is moved from the inner peripheral portion to the outer peripheral portion of the optical disk 5 and the optical pick-up 11 reaches the outermost peripheral position of the recording area, the optical pickup device 10 collides with a stopper (not shown). Immediately before it is stopped, the switch operating portion formed on the base 12 operates the outer peripheral portion detection switch 16B. The output of the outer peripheral portion detection switch 16B is sent to the system controller 6 to control the operation of the motor control circuit 7, and the drive motor 13 is stopped.

[0009]

In the drive mechanism of the optical pickup device 10 configured as described above, when the optical pickup device 10 is stopped, the recording / reproducing device is accidentally dropped or the like, and a shock or the like is applied. If
The feed spring member 15 may ride over the meshed feed screw and engage with the next feed screw. In this case, the elastic force is accumulated in the feed spring member 15 by being elastically deformed, and the feed screw is engaged with a strong impact force, so that an accident such as damage to the screw occurs.
In order to solve such a problem, as shown in FIG. 8, the tooth height H of the feed screw 14A of the feed screw member 14 (the distance from the tooth bottom to the tooth tip ≈ the engaging convex portion of the feed screw 14A and the feed spring member 15). 15A), the distance L between the feed spring member 15 and the receiving surface 12A of the base 12 is set to H> L, so that the feed spring member 15 can move as shown by a chain line in FIG. Even when the feed screw member 14 is farthest away from the member 14, the feed screw 14A of the feed screw member 14 and the engaging convex portion 15A of the feed spring member 15 are kept in a meshed state.

As described above, the optical pickup device 1
At 0, the state in which the pickup 11 reaches the innermost peripheral position and the outermost peripheral position of the recording area of the optical disc 5 is detected by the inner peripheral portion detection switch 16A and the outer peripheral portion detection switch 16B, respectively. However, the dimensional accuracy of the base 12 or the stopper, the detection switch 16A,
The open / close timing of the detection switches 16A and 16B may vary depending on the performance of 16B or the mounting accuracy. Therefore, after the base 12 and the stopper collide with each other first, the detection switches 16A and 16B may be closed to stop the drive motor 13. In this case, the feed screw member 14 is rotationally driven until the drive motor 13 stops until the base 12 of the optical pickup device 10 abuts against the stopper and the detection switches 16A and 16B are closed. As shown in FIG. 9, the feed spring member 15 formed of a spring plate material is the same as the feed screw 14 of the feed screw member 14.
The engaging portion 15A is elastically deformed between A and the base 12, and the engaging portion 15A is in a state of being engaged with the feed screw 14A. This bite state is held by the elastic force of the feed spring member 15, so that an accident occurs in which the driving operation of the optical pickup device 10 is disabled.

As described above, the conventional optical pickup device 10 requires the inner peripheral portion detection switch 16A and the outer peripheral portion detection switch 16B, and the circuit for controlling the outputs of these switches becomes complicated.
The members such as 2 or the stopper, the inner peripheral portion detection switch 16A, and the outer peripheral portion detection switch 16B must be manufactured or attached with high precision, and their precision is deteriorated due to environmental changes, changes over time, etc. There is a problem that the locking phenomenon of the device 10 occurs.

Therefore, according to the present invention, an optical pickup device which reliably prevents the locking phenomenon occurring between the feed spring member and the feed screw member and simplifies the structure by eliminating the detection switch and improves the reliability. It was proposed for the purpose of providing a drive mechanism of

[0013]

A drive mechanism of an optical pickup device according to the present invention which achieves this object includes a long-axis feed screw member that is rotationally driven, and a feed member formed on an outer peripheral portion of the feed screw member. The feed spring member is supported in a drive mechanism of the optical pickup device that reciprocally drives the optical pickup device on the radius of a disk-shaped recording medium by a feed spring member having an engaging protrusion that engages with a screw formed at one end. The base of the optical pickup device is provided with a feed spring member deviation stopper that regulates the deviation amount of the feed spring member so that the meshing state of the engaging convex portion and the feed screw is not released, and the optical pickup device is In the state where the recording medium of the recording medium is moved to the outermost position or the innermost position, the feeding protrusion is attached to the outer peripheral portion of the feed screw member with which the engaging convex portion relatively engages. The incomplete thread section which allows overcoming the feed screw engaging protrusions without being restricted by the spring member deflection stoppers, characterized in that formed in the concave groove.

Further, in the drive mechanism of the optical pickup device according to the present invention, when the optical pickup device is moved to the outermost peripheral position or the innermost peripheral position of the recording area of the recording medium, the incomplete screw portion of the feed screw member is formed. An outermost peripheral stopper means or an innermost peripheral stopper means for stopping the movement in the axial direction by coming into contact with the optical pickup device in a state where the engaging convex portion of the feed screw member is relatively engaged. And

[0015]

According to the drive mechanism of the optical pickup device of the present invention having the above-mentioned structure, the feed screw member which is rotationally driven by the drive motor and the feed screw formed on the outer peripheral portion of the feed screw member are engaged with each other. The optical pickup device is reciprocally moved in the axial direction of the feed screw member by the drive mechanism that is composed of a feed spring member that has a convex protrusion and is cantilevered to the base, and the recording area formed on the optical disc Scan over. In the feed spring member, the deviation amount is regulated by the feed spring member deviation stopper formed on the base in the direction away from the feed screw member, so that the engagement convex portion of the feed spring member and the feed screw member are controlled. The state of meshing with the feed screw is maintained.

In a state where the optical pickup device is moved to the outermost peripheral position or the innermost peripheral position of the recording area of the optical disk and abutted against the outermost peripheral stopper means or the innermost peripheral stopper means, the feed spring member is stopped. The engaging convex portion of (1) is located opposite to the incomplete screw portion that is recessed in the outer peripheral portion of the end portion of the feed screw member. The incomplete threaded portion allows the engagement projection to pass over the feed screw formed in the incomplete threaded portion regardless of the regulation of the deviation amount with respect to the feed spring member by the feed spring member deviation stopper. Therefore, even if the feed screw member is still rotating even though the optical pickup device is stopped by the stopper means, the engaging convex portion of the feed spring member overcomes the thread of the incomplete screw portion. . As a result, the feed screw member rotates in a state of idling with respect to the feed spring member. By the idling operation of the feed screw member, elastic deformation of the feed spring member is prevented, and a situation in which the engaging convex portion bites into the feed screw of the feed screw member and a locking phenomenon occurs is reliably prevented.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing a schematic structure of an optical disk device 1 including an optical pickup device 20 according to the present invention. The basic structure is almost the same as that of the conventional optical disk device 1 described above, and the same or corresponding member. The same reference numerals are given to the same, and the description thereof will be omitted. In the optical disc device 1, the configuration of the feed screw member 24 that reciprocates the optical pickup device 20 along the radius of the optical disc 5, or the optical pickup device 20 moves to the outermost position or the innermost position of the recording area of the optical disc 5. In this state, the optical pickup device 20 is accurately stopped in this state, or the rotation detecting portion 45 for detecting the rotation state of the feed screw member 24 is characterized.

The rotation detector 45 detects the rotation state of the drive motor 23 in the direction in which the optical pickup device 20 is moved from the inner peripheral side to the outer peripheral side of the recording area of the optical disk 5 by the feed screw member 24. For example, the rotation detector 45
When the drive motor 23 is in the stopped state for 1.5 seconds, the timer operates to detect the stop state of the drive motor 23 and sends an output to the motor drive circuit 7,
Stop energizing to. The optical disc device 20 of the embodiment
In the above, the rotation detecting portion 45 for detecting the rotation state of the feed screw member 24 is provided. However, for example, when the optical pickup device 20 is stopped by abutting the outermost peripheral portion stopper 28 described later, the optical pickup device 20 is stopped. The energization to the drive motor 23 may be stopped by the detection means having a timer for detecting the stop state.

As shown in FIG. 2, the optical pickup device 20 includes a base 2 molded by aluminum die casting.
2, an objective lens 21, which will be described later, an optical block 30 whose details are omitted, and a triangular prism (not shown) which is located on the optical axis of the objective lens 21 and arranged between the optical block 30 and a biaxial device which will be described later. Members such as the supported objective lens 21 are assembled. The laser beam emitted from the optical block 30 is refracted by the prism for the beam splitter and enters the objective lens 21.

Further, the optical pickup device 20 is supported by a feed screw member 24 which is rotationally driven by a drive motor 23 as will be described later, and a round bar member which is supported between pressing plates 32A and 32B fixed to a device chassis (not shown). A feed screw member 24, which is held horizontally below the optical disk 5 by a guide shaft member 33 whose outer peripheral surface is finished as a smooth surface, and which is rotationally driven on the basis of the guide shaft member 33, and a feed spring member described later. 25 is used as a driving means to reciprocate on the radius of the optical disk 5.

The base 22 is provided with a pair of guide bearings 34A and 34B through which the guide shaft member 33 penetrates in such a manner as to divide the region in which the optical block 30 and the prism are mounted so as to face each other in the width direction. The feed screw member 24 is formed on one of the side end portions of the base 22 that are integrally formed and face the guide bearings 34A and 34B in the longitudinal direction.
Is integrally formed with the feed screw receiving portion 35 into which one end of the is inserted. A feed spring member deviation stopper 36 for restricting the deviation amount of the feed spring member 25 is formed on the bottom of the base 22 so that the axis line thereof coincides with the feed screw receiving portion 35.

The objective lens 21 is provided at a substantially central portion of the base 22.
Is provided. The objective lens 21 is attached to a lens barrel formed on a lens holding member 37 that is movable in a horizontal direction and a vertical direction by a biaxial device. Two
The shaft device is formed of a synthetic resin material having flexibility, for example, a polyester elastomer, and is fixed to the base 22 by a first hinge member 38, and the width of the base 22 relative to the first hinge member 38. A second hinge member 39 integrally hinged so as to be bendable in the direction, and a base 22nd hinged integrally with the second hinge member 39 so as to be vertically bendable in the second hinge member 39. And a third hinge member 40. This third hinge member 4
0 is integrally connected with the lens holding member 37. In other words, in the biaxial device, the second hinge member 39 elastically deforms with respect to the first and third hinge members 38 and 40 so as to form a parallelogram through the hinge portions, The objective lens 21 assembled to the lens holding member 37 can be swung vertically and horizontally.

The base 22 is provided with drive coils 41A and 41B located on both sides of the lens holding member 37 for moving the objective lens 21 vertically and horizontally. These drive coils 41A and 41B
Are the yokes 42A and 42B located at the center, the coils 43A and 43B that are flatly wound so as to surround the outer peripheral portions thereof, and the plate-like shape that extends to the side portions of these coils 43A and 43B. Magnets 44A and 44B. The coils 43A and 43B are the yoke 42.
The system controller 6 includes a focus tracking coil wound around A and 42B, and a tracking coil facing the magnets 44A and 44B.
The objective lens 21 is operated via the lens holding member 37 by the servo signal supplied from the focus / tracking control circuit 9 whose operation is controlled by. The objective lens 21 collects the laser beam emitted from the optical block 30, irradiates the recording area of the optical disc 5 at a focal point, and is finely moved along the track.

The feed spring member 2 is located on the side of the base 22 opposite to the feed spring member displacement stopper 36 and is aligned with the feed screw receiving portion 35 in the axis line.
A mounting portion 31 for fixing one end portion of 5 is formed.
The feed spring member 25 formed of a spring plate member is fixed to the mounting portion 31 in a cantilever state toward the feed spring member displacement stopper 36 side, and the free end side is bent in a substantially V-shape so that An engaging protrusion 25A that meshes with the feed screw 24A formed on the outer circumference of the feed screw member 24 is formed.
In addition, the horizontal free end portion 25B of the feed spring member 25 on which the engaging convex portion 25A is formed is provided with the feed spring member displacement stopper 3
It extends above 6.

The feed screw member 24 is formed by forming a feed screw 24A on the outer peripheral portion of a round bar member, and is rotatably supported by a device chassis (not shown) so as to extend parallel to the upper side of the feed spring member 25. In addition, a transmission gear 24B that meshes with the output gear 23A of the drive motor 23 is integrally formed at one end. In the outer peripheral portion of the feed screw member 24 on one end side, in cooperation with the feed spring member 25, the optical pickup device 20 is driven to the outermost peripheral portion of the recording area of the optical disc 5, and An incomplete screw portion 29, which will be described later, is formed at the feed screw portion corresponding to the engaging convex portion 25A.

The feed screw member 24 is a transmission gear 24B that meshes with the output gear 23A when the drive motor 23 whose operation is controlled by the motor control circuit 7 is driven.
It is rotationally driven via. When the feed screw member 24 rotates, the optical pickup device 20 feeds the feed screw member 24 via the feed spring member 25 having the engaging convex portion 25A meshed with the feed screw 24A formed on the outer peripheral portion of the feed screw member 24. The optical disc 5 is moved along the axial direction of the screw member 24 in the radial direction (direction of arrows A and B in FIG. 2).

The conventional optical pickup device 10 described above.
Similarly, the engagement state between the feed screw 24A of the feed screw member 24 and the engaging convex portion 25A of the feed spring member 25 is held by the feed spring member displacement stopper 36. That is,
As shown in FIG. 4, the feed spring member deviation stopper 36 acts to regulate the elastic deviation amount in the direction in which the feed spring member 25 is separated from the feed screw member 24. The distance L between the feed spring member 25 and the receiving surface of the feed spring member displacement stopper 36 is determined by the tooth height H of the feed screw 24A of the feed screw member 24.
For H> L, and therefore
Even when the feed spring member 25 is farthest from the feed screw member 24, the feed screw 24A of the feed screw member 24 and the engaging convex portion 25A of the feed spring member 25 are kept in mesh with each other. ing. With this configuration, even when a strong shock or vibration is applied, the engaging protrusion 25A meshed with the feed screw 24A of the feed screw member 24 by the elastic force of the feed spring member 25 has the feed protrusion 2A.
4A, the optical pickup device 20 is prevented from floating in the radial direction of the optical disc 5.

As shown in FIG. 3, the entire optical pickup device 20 is guided by the guide shaft member 33 and is capable of reciprocating in the radial direction of the optical disk 5. By this movement operation of the optical pickup device 20, the objective lens 21
The laser beam spot S emitted from the optical disc 5 has an outermost peripheral position S1 to an innermost peripheral position S2 in the recording area of the optical disc 5.
Move between. In the optical disc device 1 of the embodiment,
Outermost peripheral position stopper means and innermost peripheral position stopper that accurately stop the optical pickup device 20 when the optical pickup device 20 moves to the outermost peripheral position and the innermost peripheral position of the recording area of the optical disc 5. And means are provided.

As shown in FIGS. 1 and 3, the innermost peripheral position stopper means for stopping the optical pickup device 20 at the innermost peripheral position is abutted by a switch operating portion formed on the base 22, for example. Inner circumference detection switch 26 that is closed
And an innermost peripheral stopper 27 formed on the device chassis. On the other hand, the optical pickup device 20
The outermost peripheral position stopper means for stopping at the outermost peripheral position is constituted by the outermost peripheral stopper 28 formed on the apparatus chassis and the rotation detecting portion 45 of the drive motor 23. The operation of the optical pickup device 20 moving to the innermost peripheral position and stopping is the same as that of the conventional optical pickup device 10 described above.
Immediately before 0 is abutted against the innermost peripheral stopper 27 and stopped, the inner peripheral portion detection switch 26 is closed by a switch operating portion (not shown) formed on the base 22. Output of the system controller 6
To control the operation of the motor control circuit 7, and the drive motor 23 is stopped.

On the other hand, when the optical pickup device 20 is moved from the inner peripheral portion of the optical disc 5 to the outer peripheral side and the laser beam spot S focused by the objective lens 21 reaches the outermost peripheral position S1 of the recording area of the optical disc 5. The optical pickup device 20 abuts against the outermost peripheral portion stopper 28 and is stopped. When the optical pickup device 20 stops, the rotation of the drive motor 23 also temporarily stops, and this stop state is detected by the rotation detector 45. Therefore, the timer output of the rotation detection unit 45 is sent to the motor drive circuit 7, and the stop output is sent from the motor drive circuit 7 based on the timer output to drive the drive motor 2
The power supply to 3 is stopped.

As described above, the optical pickup device 20
In the state in which the feed spring member 25 is stopped at the outermost peripheral position, the engaging protrusion 25A of the feed spring member 25 has an incomplete threaded portion 29 formed on one end side of the feed screw member 24, as shown in FIG.
Corresponding to. The incomplete screw portion 29 is the feed screw member 2
The incomplete feed screw 29A having a low tooth height is formed by forming a groove on the outer peripheral portion of the feed screw member 24 so as to remove a part of the tooth tip of the feed screw 24A of No. 4 in FIG. As shown in FIG. 4, the incomplete feed screw 29A has a tooth height lower than that of the other feed screws 24A by M. Of course, in the normal state, this incomplete feed screw 29A
The engagement state of the feed spring member 25 and the engaging convex portion 25A of the feed spring member 25 is maintained, and when the feed screw member 24 is reversely driven from the stop position, the optical pickup device 20 is moved via the feed spring member 25. It

The tooth height reduction M of the incomplete feed screw 29A is
The size is smaller than the distance L between the feed spring member 25 and the receiving surface of the feed spring member deviation stopper 36, and the feed spring member 25 abuts the feed spring member deviation stopper 36 and comes out from the feed screw member 24 most. In the separated state, FIG.
As shown by the chain line, the engaging protrusion 25A has an incomplete feed screw 29.
It is dimensioned so that it can overcome A. In other words, the tooth height reduction M of the incomplete feed screw 29A, the regulation deviation amount L of the feed spring member 25, and the tooth height H of the feed screw 24A of the feed screw member 24 are set to H>L> M. Has been done.

As described above, the optical pickup device 2
0 is the outermost position of the recording area of the optical disc 5,
The feed screw member 24 is still rotating at the time of this abutment, and tries to move the feed spring member 25 in the axial direction. However, like the engaging protrusion 25A ′ of the feed spring member 25 shown by the chain line in FIG. 5, the feed screw member 24 moves over the tooth tip of the incomplete feed screw 29A and moves to the next tooth bottom. The feed spring member 25 is in a state of idling with respect to the engaging convex portion 25A ′ of the feed spring member 25, and the feed spring member 25 is not elastically deformed. Therefore, it is possible to prevent the locked state due to the engaging convex portion 25A of the feed spring member 25 biting into the feed screw 24A of the feed screw member 24.

In the optical disc device 1 of the first embodiment described above, the switch actuating portion formed on the base 22 abuts the innermost peripheral position stopper means for stopping the optical pickup device 20 at the innermost peripheral position. Although the inner peripheral portion detection switch 26 that is closed by the above and the innermost peripheral portion stopper 27 formed on the apparatus chassis are shown, the present invention is not limited to such a constitution. For example, as shown in FIG. 6, the innermost peripheral position stopper means may also be configured by the innermost peripheral stopper 27 and the rotation detecting portion 45 of the drive motor 23, similarly to the outermost peripheral position stopper means. . In this case, when the optical pickup device 20 moves to the outermost peripheral position and the innermost peripheral position of the recording area of the optical disk 5, the engaging convex portion 25A of the feed spring member 25 corresponds to the corresponding position on the feed screw member 24. A first incomplete threaded portion 46A and a second incomplete threaded portion 46B are formed near both ends.

Further, the rotation detecting section 45 includes the feed screw member 2
4, a first rotation detecting operation for detecting the rotation state of the drive motor 23 for moving the optical pickup device 20 from the inner peripheral side to the outer peripheral side of the recording area of the optical disc 5, and the optical pickup apparatus 20 for the recording area of the optical disc 5. The second rotation detection operation of detecting the rotation state of the drive motor 23 that moves from the outer peripheral side to the inner peripheral side is performed. This second
According to the optical disc device 1 of the embodiment, since the inner peripheral portion detection switch 26 can be omitted, the structure is simplified, and the occurrence of the locking phenomenon on the inner peripheral portion side is surely prevented. The rest of the configuration and operation of the optical disc device 1 of the second embodiment are the same as those of the optical disc device 1 of the first embodiment, so description thereof will be omitted.

In each of the optical disk devices 1 of the above-described embodiments, the tooth height is increased by providing a concave groove on the outer peripheral portion of the feed screw member 24 so as to remove a part of the tooth tip of the feed screw 24A of the feed screw member 24. Although the incomplete feed screw 29A having a low height is configured, the incomplete feed screw 29A is formed by the thread portion having a low tooth height for inviting the bite formed when the outer peripheral portion of the round bar member is threaded. You may comprise.

[0037]

As described above in detail, according to the drive mechanism of the optical pickup device of the present invention, the feed screw member which is rotationally driven by the drive motor, and the feed screw member formed on the outer peripheral portion of the feed screw member. The optical pickup device is reciprocally moved on the radius of the optical disc by the feed spring member having the engaging convex portion that meshes with the screw, and the optical pickup device is moved to the outermost position or the innermost position of the recording area of the optical disc. In the state of being stopped by the outermost peripheral stopper means or the innermost peripheral stopper means, the engaging convex portion of the feed spring member is positioned so as to correspond to the incomplete screw portion recessed in the outer peripheral portion of the end portion of the feed screw member. Therefore, in the normal state, the engagement state between the feed screw of the feed screw member and the engaging convex portion of the feed spring member is reliably maintained, and the optical pick -Up device is accurately driven operation.
In addition, even when the outermost position or the innermost position of the recording area of the optical disc is moved, the engagement convex portion of the feed spring member bites into the feed screw of the feed screw member and is locked. Certainly prevented.

Further, since the detection switch for detecting the outermost circumference position or the innermost circumference position of the optical pickup device is not required, the structure of the device can be simplified and a more accurate optical disk device can be obtained. .

[Brief description of drawings]

FIG. 1 is a block diagram of a main part for explaining a schematic configuration of an optical disc device including a drive mechanism of an optical pickup device according to the present invention.

FIG. 2 is a perspective view of relevant parts for explaining the configuration of the optical pickup device.

FIG. 3 is a plan view of relevant parts for explaining a driving operation of the optical pickup device.

FIG. 4 is a longitudinal sectional view of an essential part for explaining a drive mechanism of the optical pickup device.

FIG. 5 is a longitudinal sectional view of an essential part for explaining the action of the incomplete screw part of the drive mechanism of the optical pickup device.

FIG. 6 is a principal block diagram for explaining a schematic configuration of a second embodiment of an optical disc device including a drive mechanism of an optical pickup device according to the present invention.

FIG. 7 is a principal block diagram for explaining a schematic configuration of a conventional optical disc device.

FIG. 8 is a longitudinal sectional view of an essential part for explaining a drive mechanism of the optical pickup device.

FIG. 9 is a longitudinal sectional view of an essential part for explaining the action of the incomplete screw part of the drive mechanism of the optical pickup device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Optical disk device 2 ... Spindle motor 5 ... Optical disk (recording medium) 6 ... System controller 20 ... Optical pickup device 21 ... Objective lens 22 ... Base 23 ... Drive motor 24 ... Feed screw member 24A ... Feed screw 25 ... Feed spring member 25A ... Engaging convex portion 26 ... Inner peripheral portion detection switch 27 ... Innermost peripheral stopper 28. .... Outermost part stopper 29 ... Incomplete screw part 45 ... Rotation detection part

Claims (2)

[Claims] 1. An optical system comprising: a long-screw-shaped feed screw member that is rotationally driven; and a feed spring member that has an engaging protrusion that is formed at an outer peripheral portion of the feed screw member and that engages with a feed screw at one end. In a drive mechanism of an optical pickup device that reciprocally drives the pickup device on the radius of a disk-shaped recording medium, the engagement convex portion and the feed are engaged on the base of the optical pickup device on which the feed spring member is supported. In the state where the optical pickup device is moved to the outermost position or the innermost position of the recording area of the recording medium, while providing the feed spring member deviation stopper that regulates the deviation amount of the feed spring member so as not to be released, The outer peripheral portion of the feed screw member with which the engaging convex portion is relatively engaged is an incomplete nut that allows the engaging convex portion to ride over the feed screw without being restricted by the feed spring member displacement stopper. Driving mechanism of the optical pickup device, wherein a is formed in the groove shape section. 2. The incomplete screw portion of the feed screw member and the engaging convex portion of the feed screw member are relatively moved by moving the optical pickup device to the outermost position or the innermost position of the recording area of the recording medium. 2. A drive mechanism for an optical pickup device according to claim 1, further comprising outermost peripheral stopper means or innermost peripheral stopper means for abutting against the optical pickup device to stop axial movement when engaged. .