JPH04141830A - Optical head and disk driving device - Google Patents

Abstract

PURPOSE:To realize the loading/unloading of a cartridge as against a device mainbody without the need of the vertical shift structure of the cartridge by retracting an objective lens in a prescribed standby position by means of the operation of a driving means which vertically moves the objective lens as against an optical disk for focus control. CONSTITUTION:When the cartridge 17 is inserted into the device mainbody 10, a sensor 19 detects the insertion of the cartridge 17 and transmits an on- signal to a control means 20. The focus actuator 21 of a second optical head 15 retracts a bobbin body. Thus, the objective lens is fixed in a direction getting far from the optical disk 18 and it can be moved without being abutted on a spindle motor 12 in the optical disk 18. When the hub of the optical disk 18 reaches a chucking part 13 just above the spindle motor 12, the hub is attracted, the cartridge 17 descends and it is set in the prescribed position of the spindle motor 12. Thus, the smooth loading/unloading of the cartridge as against the cartridge device mainbody can be realized without the need of the vertical shift structure of the cartridge.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an optical head and an optical disk drive device for recording and reproducing information on and from an optical disk (including a magneto-optical disk).

(Prior Art) As shown in the multi-optical head control method disclosed in Japanese Patent Application Laid-Open No. 2-165425, a device equipped with multiple optical heads has been proposed in order to increase the access speed during recording and reproduction of an optical disk. There is.

FIGS. 8(a) and 8(b) are explanatory diagrams for explaining the operation of an example of a conventional optical disk drive device having a plurality of optical heads, in which 1 is the main body of the device, 2 is a spindle motor, and 3 is a first A lower chassis 5, which holds the optical head 4 and is fixed to the apparatus main body 1, holds the second optical head 6,
An upper chassis 7 is provided on the main body 1 of the apparatus so as to be movable up and down, and a cartridge 7 stores an optical disk 6 therein.

In FIG. 8(a), when the cartridge 7 is inserted, the upper chassis 5 is in a raised state relative to the lower chassis 3, and the first... This allows passage between the second optical heads 4 and 6 and attachment to the spindle motor 2. When the cartridge 7 is attached to the spindle motor 2, the upper chassis 5 is lowered to move the first and second cartridges toward the optical disk 6, as shown in FIG. 8(b). Second optical head 4, 6
Recording and playback operations are now possible.

In addition, as in the small optical disc device disclosed in Japanese Patent Application Laid-Open No. 1-211265, the rotating shaft of the motor that rotates the optical disc is made movable in the axial direction, so as to prevent the cartridge from moving undesirably when the cartridge is attached to and removed from the main body of the device. A loading mechanism is also known that moves the rotating shaft.

(Problems to be Solved by the Invention) The conventional device described above does not require a mechanism to move the cartridge up and down in order to load and unload the cartridge, but the chassis that holds the optical head or the rotation shaft of the motor is on the move. However, in general, in an optical disk drive device, the positional relationship between the motor and the optical head is set with high precision, and in a configuration in which the chassis and the rotating shaft move up and down, there is a problem that the positional precision is likely to be distorted.

The object of the present invention is to eliminate the need for a structure for vertically moving the cartridge, and without affecting the positional accuracy of each part.
An object of the present invention is to provide an optical head and an optical disk drive device in which a cartridge can be inserted into and removed from an apparatus main body.

(Means for Solving the Problems) In order to achieve the above object, the optical head of the present invention includes an objective lens for forming a beam spot on the recording surface of an optical disc, and an objective lens that is attached to the optical disc for focus control. The optical head is characterized in that the objective lens is configured to be able to be retracted to a predetermined standby position by the operation of the drive means.

Further, the optical disc drive device of the present invention includes an objective lens for forming a beam spot on the recording surface of an optical disc housed in a cartridge, and a drive means for moving the objective lens up and down with respect to the optical disc for focus control. In an optical disk drive device which has an optical head and performs recording and reproduction on an optical disk, the drive means is operated to retract the objective lens to a position away from the optical disk when the cartridge is inserted into and removed from the device main body. It is characterized by comprising a control means.

(Function) According to the above optical head, the objective lens that moves up and down for focus control can be retracted to a predetermined standby position by the driving means, and the movement of the objective lens is performed during the focus control operation. This is done with precision, and if the cartridge is inserted or removed while the objective lens is in the standby position, the insertion or removal operation can be performed without any hindrance, and will not disturb the positional relationship of the various parts.

Further, according to the above-mentioned optical disc drive device, when the cartridge is inserted into or removed from the main body of the device, the objective lens, which moves up and down for focus control, can be controlled so as to be retracted to a position away from the optical disc by operating its driving means. The cartridge can be inserted and removed smoothly, and the objective lens can be moved with precision within the focus control operation without disturbing the positional relationships of the various parts.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is an explanatory diagram schematically showing the configuration of an embodiment of an optical disk drive device of the present invention, and FIG. 2 is an explanatory diagram of main parts of the embodiment of FIG. A chassis fixed to the main body lO and having an opening on the cartridge insertion side, 1
2 is a spindle motor fixed to the lower part of the chassis 11; 13 is a chucking part made of a magnet provided on the spindle motor 12; 14 is a first optical head held in the lower part of the chassis 11; 15 is the upper part of the chassis 11. 1st to
A second optical head is held opposite to the optical head 14, 16 is an eject button provided on the front of the device main body 10, 17 is a cartridge containing an optical disc 18, and 19 is provided inside the device main body 10. , a sensor for detecting the insertion of the cartridge 17; 20 a control means including an electric circuit that outputs a control signal in response to the ON signal of the eject button 16 and the sensor 19; Based on the above 1. The second optical head 14.15 is a focus actuator which is a driving means for vertically moving the objective lens unit 22, which will be described later.

FIG. 3 is an exploded perspective view showing the main parts of the optical head of the present invention used in FIG. The objective lens unit 24 is integrated with the objective lens unit 22, has a focusing coil 25 wound around it, and has a pair of tracking coils 26 at opposing positions on the sides of the focusing coil 25.
27 is a receiving hole provided in the center of the bobbin body 24, and 28 is a supporting shaft 29 that is loosely fitted into the receiving hole 27.
A substrate supporting a pair of tracking magnets 30 disposed to face each other and a pair of focusing magnets 31 disposed to face a part of the focusing coil 25, The focus actuator 2 includes the focus coil 25 and focus magnet 31.
1 is constituted, and a tracking actuator is constituted by a tracking coil 26 and a tracking magnet 30.

FIG. 4 is an external perspective view of the cartridge, and FIG. 5 is an exploded perspective view of the main parts of the cartridge shown in FIG. It can be exposed to the outside and has a chucking part 13 and a first chucking part 13 in the center. Openings are formed on the front and back surfaces of the cartridge body 32 so that the second optical heads 14 and 15 can enter therein, 34 is a beam connecting the front facing parts of the opening 33, and 35 is the opening of the opening 33. The shutter receiver formed in the surrounding cartridge body 32 is a recess, and the shutter holder 36 is slidable into a cover integral 37 made of a thin metal plate that is approximately U-shaped when viewed from the side, and a guide groove 38 formed in the front side of the cartridge body 32. The shutter 40 is made up of a plastic slider 39 and is a metal hub provided at the center of the optical disc 18 .

Next, the operation of the above embodiment will be explained.

First, when the focus actuator 21 receives a focus control signal or a control signal from the control means 20 and energizes the focus coil 25, the focus actuator 21 moves the bobbin body 24 by electromagnetic action with the focus magnet 31 and guidance of the support shaft 29. However, when receiving a control signal from the control means 20, it is pulled to the bottom so as to be retracted to the standby position shown in FIG. 6(a), and when receiving a focus control signal, ), perform vertical fine movement for focus control in the range shown in (C).

The distance of the objective lens 23 with respect to the optical disc 18 is changed by vertical slight movement of the bobbin body 24 based on the focus control signal, and the diameter of the beam spot that illuminates the recording surface of the optical disc 18 can be controlled.

Further, in the tracking actuator 26, 30, when each tracking coil 26 is energized in response to a tracking control signal, the bobbin body 24 rotates around the support shaft 29 due to electromagnetic interaction with the tracking magnet 30.
By moving the objective lens 23, tracking control of the beam spot is performed with respect to an information track (not shown) on the recording surface of the optical disk 18.

Next, the loading operation in this embodiment will be explained.

As shown in FIG. 7(a), when the cartridge 17 is inserted into the main body 10 of the apparatus, the shutter 36 of the cartridge 17 is opened and the opening 33 is opened.

At this time, the sensor 19 detects the insertion of the cartridge 17 and outputs an on signal to the control means 20, and the second optical head 15
The focus actuator 21 retracts the bobbin body 24 to the standby position shown in FIG. 6(a). Therefore, the objective lens 23 is fixed in the direction away from the optical disc 18 and does not come into contact with the periphery of the opening 33 of the cartridge 17 and the beam 34, and the hub 40 of the optical disc j8 also does not come into contact with the spindle motor 12. You can move without touching.

As shown in FIG. 7(b), the hub 40 of the optical disk 18 is attached to the chucking portion 1 directly above the spindle motor 12.
3, the hub 4o is attracted by the magnetic force of the chucking portion 13, and the cartridge 17 is lowered and set at a predetermined position in the spindle motor 12, as shown in FIG. 7(C). When the setting of the cartridge 17 is confirmed by an appropriate sensor, the power supply to the focusing coil 25 of the focus actuator 21 is stopped via the control means 20. Then, the bobbin body 24 descends and the objective lens 23 protrudes to a position where it can focus on the optical disc 18.

In this state, the spindle motor 12 and the first. Since the second optical heads 14 and 15 are held and fixed to the same chassis 11, there is no change in their positional relationship.

Also number 1. The second optical heads 14 and 15 are in a state where they can perform recording and reproduction on the image recording surface of the optical disc 18 under focus control and tracking control.

To eject the cartridge 17, press the eject button 16.
This is done by pressing . That is, when the eject button 16 is pressed, an ON signal is sent to the control means 20, and in response to the control signal from the control means 20, the focus actuator 21 of the second optical head 15 moves the bobbin body 2.
4 to the standby position. In this state, cartridge 1
7 to the outside of the apparatus main body 10, and the objective lens 23 does not become an obstacle to the movement of the cartridge I7.

In the above embodiment, the device main body 1 of the cartridge 17
Although the description has been made assuming that only the second optical head 15 is retracted to the standby position when the second optical head 14.1 is inserted into or removed from the
5 may be retracted, and it is sufficient to retract at least one optical head.

(Effects of the Invention) As described above, according to the present invention, by operating the driving means that moves the objective lens up and down with respect to the optical disk for focus control, the objective lens is moved to a predetermined standby position, for example, away from the optical disk. It is possible to provide an optical head and an optical disk drive device that can be retracted to a position, do not require a structure for vertically moving the cartridge, and can be smoothly inserted into and removed from a cartridge device main body without affecting the positional accuracy of each part.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a schematic configuration of an embodiment of an optical disk drive device of the present invention, FIG. 2 is an explanatory diagram of main parts of the embodiment of FIG. 1, and FIG. FIG. 4 is an exploded perspective view of one embodiment, FIG. 4 is an external perspective view of the cartridge, FIG. 5 is an exploded perspective view of main parts of the cartridge in FIG.
), (b), and (c) are explanatory diagrams of the operation of the optical head in FIG. 3, and FIG. 7(a). 8(b) and (C) are explanatory diagrams for explaining the operation of the optical disc drive device of FIG. 1, and FIGS. 8(a) and (b) are explanatory diagrams for explaining the operation of the conventional optical disc drive device. 10...Device body, 14.15 Optical head, 17
...Cartridge, 18...Optical disc, 20.
...control means, 21.. drive means, 22. objective lens unit, 23.. objective lens.

Claims (2)

[Claims] (1) In an optical head comprising an objective lens for forming a beam spot on the recording surface of an optical disk, and a driving means for moving the objective lens up and down with respect to the optical disk for focus control, the operation of the driving means An optical head characterized in that the objective lens is configured to be retractable to a predetermined standby position. (2) It has an optical head equipped with an objective lens for forming a beam spot on the recording surface of the optical disc housed in the cartridge, and a driving means for moving the objective lens up and down with respect to the optical disc for focus control. , an optical disk drive device for recording and reproducing data on and from an optical disk, comprising a control means for operating the drive means to retract the objective lens to a position away from the optical disk when the cartridge is inserted into and removed from the device main body. An optical disc drive device characterized by: