JPH03154232A - Feed controller for optical pickup - Google Patents

Abstract

PURPOSE:To detect a recording range accurately even when a tilt plate is tilted by providing a position detection member to a chassis and forming the abutting part of a support member in abutting thereon to be a circular-arc shape in taking a distance from the turning center to the detection member as a radius. CONSTITUTION:If a disk 5 is bent downward, a tilt plate 4 is turned around a support part 4d and tilted in a parallel with the disk 5. Then the pickup 1 is moved in parallel with the tilt plate 4 and when the pickup reaches an inner circumferential end of the disk 5, a press contact face 19b of a switch 19 depresses an actuator 7a and a sensor switch 7 detects the position. Then the abutting face 19b is formed to be a circular arc taking the distance from the driving center 4d to the detection part 7a as a radius. Moreover, if the disk 5 is bent upward and the pickup reaches a detection part 6a, the operation is similar to above. Thus, even when the tilt plate is tilted, the recording range is accurately detected.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a feed control device for an optical pickup, and more specifically, the present invention relates to a feeding control device for an optical pickup. In addition to adjusting the angle in accordance with the warpage of the disk, the optical pickup can be moved back and forth between the inner and outer edges of the disk, and the position of the optical pickup at both ends or one end can be switched. This invention relates to a feed control device for an optical pickup that is capable of reversing the feed direction, stopping the feed, etc. by detecting the same using electrical means such as the above.

[Conventional technology]

Information signals are normally recorded and reproduced on a disk such as a laser disk using an optical pickup.

At this time, the information signal needs to be recorded in a predetermined range from the inner edge to the outer edge of the disc. Therefore, the optical pickup is moved back and forth in the radial direction of the disk.

The above-mentioned reciprocating movement is performed by a feed control device of the optical pickup. As shown in FIG. 7, this feed control device includes a chassis 8 provided with a spin motor 9 for rotating a disk 5 via a turntable 10, and a tilt plate 4 disposed above the chassis 8. , and a housing 2 that holds an optical pickup 1.

As shown in FIG.
and a guide hole 2a into which the guide shaft 3 is inserted are formed at both ends.

As a result, the housing 2 and the optical pickup 1 are
Guide hole portion 2a, guide shaft 3, and guide portion 2b
The guide surface 4c is moved back and forth by sliding contact with the guide surface 4c.

The tilt plate 4 also has a fulcrum portion 4 as shown in FIG.
d and 4d are formed at the center position on the turntable 10 side. These fulcrum portions 4d, 4d are rotatably supported by fulcrum support portions 8a, 8a provided on the chassis 8, and serve as the center of rotation of the tilt plate 4. Furthermore, the above-mentioned tilt plate 4 is provided with a tilt adjustment drive mechanism (not shown), and this tilt adjustment drive mechanism usually includes:
For example, a motor engaged with a reduction gear is used.

As a result, the tilt plate 4 can be rotated about the fulcrum parts 4d by the above-mentioned tilt drive mechanism, and as shown in FIG. Even if the disk 5 is warped, the orthogonal state can be maintained by adjusting the inclination of the tilt plate 4.

Further, since the optical pickup 1 that moves back and forth records information signals in a predetermined recording range of the disk 5, it needs to be stopped at predetermined positions on the inner and outer edges of the disk 5. be.

Therefore, the feed control device includes detection switches 6 and 7 capable of detecting predetermined positions on the inner and outer circumferential ends, and is formed in the housing 2 so as to come into contact with each of these detection switches 6 and 7. Projections 2C and 2d are provided.

Furthermore, it is desirable that the predetermined positions on the inner and outer circumferential ends of the disk 5 be detected with high precision even if the disk 5 is warped. Therefore, in the conventional feed control device, the above-mentioned detection switches 6 and 7 are fixed to the tilt plate 4 that supports the housing 2. As a result, even when the tilt plate 4 is rotated in response to the warping of the disk 5, the detection switches 6 and 7 rotate together with the housing 2, and the detection switches 6 and 7 rotate in the direction of travel of the housing 2.
The actuator parts 6a and 7a are always in the same direction. Therefore, the position where the actuator parts 6a and 7a of the detection switches 6 and 7 are pressed by the protrusions 2c and 2d of the housing 2 is the inner circumference of the disc 5 even if the tilt plate 4 is tilted due to the warp of the disc 5. They are in predetermined positions on the end side and the outer peripheral end side.

In this way, the conventional optical pickup feed control device
By rotating and tilting the tilt plate 4, the optical axis of the optical pickup 1 can be maintained perpendicular to the disk 5, and even when the tilt plate 4 is tilted, the recording range of the disk 5 can be maintained. By being able to accurately detect the optical pickup 1, unnecessary movement of the optical pickup 1 can be prevented.

[Problem to be solved by the invention]

However, in the above-mentioned conventional optical pickup feed control device, it is difficult to wire the detection switches 6 and 7, and this wiring has a negative effect on the rotation of the tilt plate 4. This may result in a delay in access time.

That is, as shown in FIG. 10, a wiring material 15 is connected to the detection switches 6 and 7, and this wiring material 15 is arranged in a portion avoided from the movable range of the optical pickup 1. It is necessary that the Therefore, the wiring members 15 connected to the detection switches 6 and 7 are assembled while being fixed at the outer periphery of the tilt plate 4 by a plurality of binding members 16 to protect the wiring members 15 and prevent play. After being fixed to 8 with a binding member 16, it is connected to a circuit board (not shown) via a connector 17, for example.

However, the wiring material 15 described above becomes a factor that makes the load generated when rotating the tilt plate 4 unstable. This unstable load affects the tilt adjustment drive mechanism that rotates the tilt plate 4, and causes fluctuations in the operating speed at which the motor rotates the tilt plate 4 with a constant torque, for example. This variation in operating speed causes variations and delays in the access time required to adjust the inclination of the tilt plate 4 to correspond to the warpage of the disk (not shown).

Therefore, in order to stabilize the load generated when the tilt plate 4 rotates, the wiring material 15 is required to be made of an elastic material, and the wiring route must be restricted so that the load is light. However, this restriction on the wiring route requires higher precision in the routing position of the wiring material 15, which in turn leads to an increase in the number of binding members 16 and the complexity of the shapes of the tilt plate 4 and the chassis 8. I will do it. Furthermore, since the above-mentioned wiring is performed manually, it is difficult to quantitatively suppress variations due to manual work, and the work time is increased due to the positioning of the wiring.

In this way, the conventional optical pickup feed control device
Wiring material 15, wiring work, tilt plate 4 and chassis 8
By taking many measures and limiting the shape of the tilt plate 4,
However, even with these measures and restrictions, it is not a fundamental solution to stabilize the load fluctuations mentioned above. .

Therefore, in the present invention, fluctuations in the load that occur when rotating the tilt plate 4 can be stabilized without taking measures or restrictions on the wiring material 15, the wiring work, or the shape of the tilt plate 4 or the chassis 8. It is an object of the present invention to provide an optical pickup feed control device that can accurately detect the recording range of the disk 5.

[Means to solve the problem]

In order to solve the above problems, an optical pickup feed control device according to the present invention includes an optical pickup that records and reproduces information signals by irradiating a disk with light, and a holding member such as a housing that holds the optical pickup. The holding member is slidably supported by a guide surface or the like, and the tilt plate is formed with a fulcrum portion serving as a center of rotation, and the holding member is brought into contact with an abutting portion formed on the sliding holding member. , a chassis in which a position detection member such as a detection switch that detects the inner and outer edges of a recording range of the disk, and a fulcrum support part that rotatably supports a fulcrum part of the tilt plate; In a feed control device for an optical pickup, each of the position detection members is provided on the chassis, and the contact portion of the holding member that abuts these position detection members has a section from the center of rotation to each position detection member. It is characterized in that each contact surface is formed in the shape of an arc whose radius is the distance.

[For production]

According to the above configuration, the tilt plate is formed with a fulcrum portion serving as a center of rotation, and this fulcrum portion is rotatably supported by a fulcrum support portion formed on the chassis. The above-mentioned center of rotation is the center of the moment of inertia, and the fulcrum portion serving as the center of rotation and the fulcrum support portion that supports the fulcrum portion do not become a factor that fluctuates the load generated when the tilt plate rotates. Therefore, the tilt plate on which the fulcrum part and the fulcrum support part are formed and the chassis are completely separated from each other with respect to the load generated during rotation.

Furthermore, position detection members for detecting recording ranges are provided on each chassis. Therefore, the wiring paths for wiring these position detection members can be formed only on the chassis without forming them on the tilt plate. As a result, the load during rotation does not vary due to the wiring of the position detection member since the above-mentioned tilt plate and chassis are completely separated in terms of load.

Furthermore, the abutting part of the holding member that makes it possible to detect the recording range by abutting against the position detecting member has a contact surface between each position detecting member and the abutting part, and these abutting surfaces are each formed in an arc shape whose radius is the distance from the center of rotation to each position detection member. Therefore, the recording range can be accurately detected even when the tilt plate rotates about the fulcrum and tilts to accommodate the warpage of the disk.

In this way, the optical pickup feed control device can accurately detect the recording range, and the degree of freedom is increased because the wiring route of the position detection member does not affect the rotation of the tilt plate. This increased degree of freedom makes it possible to stabilize load fluctuations that occur when the tilt plate rotates, without having to take measures or restrict wiring materials, wiring work, or the shape of the tilt plate or chassis. I have to.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 6. For convenience of explanation, the same reference numerals are added to the same constituent members as in the conventional example shown in FIGS. 7 to 10.

The optical pickup feed control device according to this embodiment has a second
As shown in the figure, connect the optical axis of optical pickup 1 to disk 5.
It has a tilt plate 4 that can always be maintained perpendicular to the tilt plate 4. As shown in FIG. 1, this tilt plate 4 has fulcrum portions 4d, which serve as centers of rotation, formed at both ends in the width direction, and an opening 4e formed in the center.

As shown in FIG. 2, above the opening 4e,
An optical pickup 1 is disposed so as to be movable back and forth, and the optical pickup 1 is provided with an objective lens 1a that irradiates the disk 5 with, for example, a laser beam. The objective lens la forms a light spot on the disk 5 to record and reproduce information signals.

Further, the optical pickup 1 described above is held by a housing 2 that is a holding member. As shown in FIG. 1, this housing 2 has a guide hole 2a and a guide part 2b formed in the width direction of the tilt plate 4, and a switch which is a contact part described later on the guide part 2b side. A portion 19 is formed to be located below the tilt plate 4.

A guide shaft 3 is slidably fitted into the guide hole 2a, and both ends of the guide shaft 3 are supported by support members 4a and 4b formed on the tilt plate 4. On the other hand, the guide portion 2b is formed in a U-shape, as shown in FIG. 3, and is configured to sandwich a guide surface 4c formed on the tilt plate 4. Thereby, the housing 2 can be moved in the horizontal direction with respect to the tilt plate 4 by restricting the guide hole portion 2a and the guide portion 2b by the guide shaft 3 and the guide surface 4c.

Further, as shown in FIG. 1, a rotary shaft is inserted through the opening 4e formed in the tilt plate 4 toward the support member 4b. As shown in FIG. 2, the rotating shaft 18 is provided with a turntable 1o at the upper end of the tilt plate 4 for supporting and rotating the disk 5. On the other hand, a spin motor 9 for rotating the rotary shaft 18 is provided at the other end of the rotary shaft 18 .

The spin motor 9 is fixed to a chassis 8, and the chassis 8 has a fulcrum that rotatably supports the fulcrum portions 4d and 4d of the tilt plate 4, as shown in FIGS. Support portions 8a, 8a are formed at the center on the rotating shaft 18 side.

As a result, even if the disk 5 is warped, the tilt plate 4 and the disk 5 can be connected to the above-mentioned fulcrum portions 4d and 4d.
Parallelism is maintained by rotating around .

The chassis 8 also includes switch support parts 21 and 2.
Detection switches 6 and 7, which are position detection members, are provided on the back surface via 1. These detection switches 6 and 7 are
The chassis 8
are provided opposite to each other at both ends in the longitudinal direction. Also,
The detection switches 6 and 7 have actuator parts 6a and 6a that open and close contact parts built into the detection switches 6 and 7, respectively.
7a is provided. These actuator parts 6a
- 7a is provided through the chassis 8 so as to be located above the chassis 8, and is adapted to come into contact with and be pressed by the switch portion 19 formed in the above-mentioned housing 2.

The above switch section 19 includes actuator sections 6a and 7a.
Contact surfaces 19a and 19b that come into contact with are formed on both side surfaces. The heights of these contact surfaces 19a and 19b are set to such an extent that the contact surfaces 19a and 19b of the switch section 19 and the actuator sections 6a and 7a come into contact with each other when the tilt plate 4 rotates to the maximum. There is. In addition, the contact surfaces 19a and 19
b is formed into a circular arc shape, and as shown in FIG. The contact surface 19b side is formed along a circumference defined by radius R1, and the radius R2 is the distance from the center of rotation of the fulcrum portion 4d to the actuator portion 7a of the detection switch 7. .

As a result, the position at which the switch section 19 presses the actuator sections 6a and 7a of the detection switches 6 and 7 is determined when the tilt plate 4 rotates about the fulcrum section 4d, as shown in FIGS. 4 and 5. But it is always kept constant.

In this embodiment, the detection switches 6 and 7 are provided on the back surface of the chassis 8, but the present invention is not limited to this, and if they do not contact the tilt plate 4, they may be provided on the top surface of the chassis 8. It's okay.

In the above configuration, the operation of the feed control device will be described below with reference to FIGS. 4 and 5.

First, as shown in FIG. 4, when the disk 5 is bent downward, the tilt plate 4 is tilted at A with the fulcrum 4d as the center.
direction, and the angle of inclination becomes parallel to the disk 5. At this time, the optical pickup l is mounted on the tilt plate 4.
Since it moves parallel to the disc 5, it is possible to always make the optical axis from the optical pickup 1 perpendicular to the disc 5.

When the optical pickup 1 is located on the inner circumferential edge side of the disk 5, the lower part of the contact surface 19b of the switch section 19 comes into contact with the actuator section 7a, and this actuator section 7a is pressed, so that detection is performed. A contact section built into the switch 7 is opened and closed, and it is detected that the inner end of the recording range has been reached. Also, the optical pickup 1 is connected to the disk 5.
When the upper part of the contact surface 19a of the switch part 19 contacts the actuator part 6a, the actuator part 6a is pressed, and the contact part built in the detection switch 6 is activated. It is detected that the recording range has been opened or closed and that the outer peripheral end of the recording range has been reached.

On the other hand, as shown in FIG.
direction, and the angle of inclination becomes parallel to the disk 5. As in the case where the disk 5 is warped downward, the optical pickup 1 moves parallel to the tilt plate 4, so the optical axis from the optical pickup 1 is always perpendicular to the disk 5. becomes possible.

When the optical pickup 1 is located on the inner peripheral end side of the disk 5, the upper part of the contact surface 19b of the switch section 19 comes into contact with the actuator section 7a, and this actuator section 7a is pressed, so that detection is performed. A contact section built into the switch 7 is opened and closed, and it is detected that the inner end of the recording range has been reached. Also, the optical pickup l is on the disk 5.
, the lower part of the contact surface 19a of the switch section 19 contacts the actuator section 6a, and the actuator section 6a is pressed, thereby reaching the outer circumferential end of the recording range. is detected.

In this way, the optical axis of the optical pickup 1 and the disk 5 can maintain a perpendicular state without being affected by the warping of the disk 5. Also, disk 5
Even if the tilt plate 4 is tilted, the recording range is accurate because the contact surfaces 19a-19b are formed in an arc shape along the circumference of the radius R1 and the radius R2, as shown in FIG. It becomes possible to detect Therefore, no matter how the optical pickup 1 performs tilt adjustment, which is the rotation of the tilt plate 4 corresponding to the disk 5, the amount of movement is constant, and the optical pickup 1 is reversed or stopped at the same position.

Next, a case where the detection switches 6 and 7 are provided and wired on the upper surface of the chassis 8 will be described below based on FIG. 6.

Wiring material 15 connectable to the circuit board via connector 17
are arranged from the lower surface of the chassis 8, and after being fixed with binding members 16, 16 on this lower surface, are pulled out to the upper surface through openings 8c, 8c formed in the chassis 8, and connected to the detection switches 6, 7. ing. At this time, the detection switches 6 and 7 are provided on the chassis 8, and the wiring material 15 connected to the detection switches 6 and 7 does not come into contact with the tilt plate 4.

By the way, the above-mentioned tilt plate 4 is formed with fulcrum portions 4d that serve as rotation centers, and these fulcrum portions 4d are rotatably supported by fulcrum support portions 8a formed on the chassis 8. . The above rotation center is the center of the moment of inertia, and the fulcrum portion 4d and the fulcrum support portion 8a, which are the rotation centers, do not become a factor that changes the load generated when the tilt plate 4 rotates. Therefore, the tilt plate 4 and the chassis 8, which are engaged at the fulcrum portion 4d and the fulcrum support portion 8a, are completely separated from each other with respect to the load generated during rotation.

Therefore, since the wiring path between the detection switches 6 and 7 and the circuit board is formed only in the chassis 8, the wiring material 15 arranged in this wiring path can vary the load generated when the tilt plate 4 rotates. I have nothing to do. In addition, this wiring route is
Even if the detection switches 6 and 7 are provided on the lower surface of the chassis 8, they are still completely separated from the tilt plate 4.

Thereby, the degree of freedom of the wiring route increases because it does not affect the above-mentioned load fluctuation, and it becomes possible to simplify the shapes of the tilt plate 4 and the chassis 8. In addition, the increase in the degree of freedom described above also reduces the accuracy of the routing position of the wiring material 15, and this reduction in accuracy reduces the number of binding members 16 and shortens the time required for manual wiring. enable.

In this way, the feed control device according to the present embodiment has the wiring material 1
5. It is possible to stabilize the load fluctuations that occur when rotating the tilt plate 4 without taking any measures or restrictions on the wiring work or the shape of the tilt plate 4 or the chassis 8, and The recording range can now be detected accurately.

〔Effect of the invention〕

As described above, in the optical pickup feed control device according to the present invention, the position detection members are respectively provided on the chassis, and the contact portions of the holding members that come into contact with these position detection members are In this configuration, arc-shaped abutting surfaces each having a radius equal to the distance to the position detection member are formed.

As a result, the wiring route of the position detection member does not affect the load generated when the tilt plate rotates, increasing the degree of freedom of the wiring route, and ultimately reducing the wiring material, wiring work, and shape of the tilt plate and chassis. Even without any measures or restrictions,
It becomes possible to stabilize the above-mentioned load fluctuations.

At the same time, since the contact surface is formed in an arc shape with a radius equal to the distance from the center of rotation to each position detection member, the contact position between the contact portion and each position detection member is determined by the rotation of the tilt plate. Even when the recording area is moved and tilted, it remains constant and the recording range can be accurately detected.

[Brief explanation of the drawing]

1 to 6 show one embodiment of the present invention. FIG. 1 is a plan view of the feed control device. FIG. 2 is a front view of the feed control device. FIG. 3 is a sectional view taken along the line XX of the feed control device in FIG. 1. FIG. 4 is an explanatory diagram showing the operation of the feed control device when the disk is along the downward direction. FIG. 5 is an explanatory diagram showing the operation of the feed control device when the disk is in the upward direction. FIG. 6 is a perspective view of the feed control device. 7 to 10 show conventional examples. FIG. 7 is a front view of the feed control device. FIG. 8 is a plan view of the feed control device. FIG. 9 is a sectional view taken along the line X=X of the feed control device in FIG. 8. FIG. 10 is a perspective view of the feed control device. 1 is an optical pickup, 2 is a housing (holding member), 2
a is a guide hole portion, 2b is a guide portion, 3 is a guide shaft, 4 is a tilt plate, 4d is a fulcrum portion, 5 is a disk, 6 and 7
is a detection switch (position detection member), 8 is a chassis, 8a
15 is a wiring member, 19 is a switch portion (contact portion), and 19ab is a contact surface.

Claims (1)

[Claims] 1. An optical pickup that records and reproduces information signals by irradiating light onto a disk, a holding member that holds the optical pickup, and a holding member that supports the holding member in a slidable manner and that rotates. A position where the tilt plate in which the central fulcrum part is formed comes into contact with the abutting part formed in the sliding holding member and detects the inner peripheral end side and the outer peripheral end side of the recording range of the disk. In an optical pickup feed control device having a detection member and a chassis formed with a fulcrum support portion that rotatably supports a fulcrum portion of the tilt plate, the position detection members are each provided on the chassis, An optical pickup characterized in that each of the contact portions of the holding member that contacts the position detection member is formed with an arc-shaped contact surface whose radius is the distance from the center of rotation to each position detection member. feed control device.