KR19980030558A - Pick-up unit feeding unit of optical disc player - Google Patents

Abstract

The present invention discloses a pickup unit feeding apparatus of an optical disc player.

In a pickup unit feeding apparatus of a general optical disc player, the pickup unit slides and transfers the speed on the inner and outer circumferential sides of the optical disc while increasing or decreasing its speed through a very complicated servo circuit. Therefore, the design is very difficult, and in particular, a high speed mechanism causes a problem that stable recording / playback cannot be performed.

In order to solve this problem, the present invention simplifies the servo circuit by varying the rotational speed of the transfer screw based on the point of time at which the pickup unit is located on the inner and outer circumferential sides of the optical disk. Of course, stable recording / reproducing can be performed even at a high speed mechanism.

Description

Pick-up unit feeding device of optical disc player

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk player, and more particularly, to a pick-up unit feeding apparatus for recording / reproducing from an optical disk.

In general, an optical disc player includes a loading unit in which a tray is loaded, a pick-up unit that scans a laser beam toward an optical disc, and reads information through a beam reflected from the optical disc, It is divided into a feeding part for slidingly transporting the pickup unit in the radial direction of the optical disk, and a chucking part and a tilting part for seating and clamping the disk on the turn table.

In such an optical disc player, in particular, the feeding unit is one of the very important components for precisely conveying the pickup unit for recording / reproducing from the optical disc.

Fig. 1 shows a pickup unit feeding device of such a general optical disc player.

This is because an optical disk is mounted on a turntable which is rotationally driven by a spindle motor (not shown), and a pickup unit 2 for reading a record from the optical disk about the optical disk, that is, in the radial direction of the optical disk, is provided. Sliding conveyed by the feeding device.

At this time, one end of the pickup unit 2 is axially supported by the guide member 3 so as to be slidable, and the other end thereof receives power from the feeding means.

Looking at the structure of the feeding means, on the main chassis (not shown) adjacent to the turn table is placed a feeding motor (M) in which the gear 4 is fixed on the rotation axis, the gear in the position adjacent to the gear (4) (5) is meshed.

In addition, at the center of the gear 5, a feed screw 6 whose shafts are rotatably supported on the main chassis is axially supported. Then, the transfer screw 6 is screwed with one side of the pickup unit 2, as a result of receiving power from the feeding motor (M), when the transfer screw 6 is driven to rotate, the pickup unit (2) Is slide-transferred along the transfer screw 7, that is, in the radial direction of the optical disc, to perform recording / reproducing.

However, in the pickup unit feeding apparatus of such a conventional optical disc player, since the servo control cannot be performed very precisely, a problem arises that a stable disc recording / reproducing operation is difficult.

The reason why servo control cannot be performed very precisely in this way is that the disc format per unit time is adopted to have a constant linear velocity in the inner and outer periphery in terms of the signal format of the disc. The amount of data read from should always be the same. Therefore, in the inner circumference, the track change is so severe that the feeding device also has to cope with it, that is, the variable deceleration ratio must be obtained, but the variable deceleration is achieved through the engagement of the plurality of gears 4 and 5 as in the prior art. It is difficult to obtain the dobby and therefore it is not easy to perform the servo control very precisely. In addition, in order to solve such a problem, since the servo control circuit must be very complicated, the design is difficult.

On the other hand, such a problem is particularly significant in recording / reproducing from an optical disk rotating at high speed, such as a CD-ROM driver or the like which is widely used in recent years.

The present invention was created to solve the above problems of the conventional pickup unit feeding device, and can accurately read signals even from a disk rotating at high speed, and in particular, the pickup unit feeding of the optical disc player can simplify the servo circuit. The object is to provide a device.

In order to solve such a problem, the pickup unit feeding apparatus of the optical disc player according to the present invention includes a pickup unit whose one end is slidably supported on the base and whose other end is fastened to the transfer screw, and which is adjacent to the pickup unit. A feeding motor on which the spur gear of a predetermined length is axially supported on the rotating shaft and between the feeding motor and the pick-up unit, and variably transmits power from the feeding motor onto the feed screw. In the pickup unit feeding device of the optical disc player including a speed shift means for transmitting to vary the rotational speed of the feed screw, the speed displacement means is press-installed at the end of the transfer screw, the reference to the end of the transfer screw First feed with a relatively large number of first gears and a small number of second gears Eel; A feed shaft positioned between the feeding motor and the feed screw and slidably installed on the base in a sliding feed direction of the pickup unit; A second feed shaft supported by an outer circumferential surface of the feed shaft and having a first gear portion which is selectively engaged with the first gear portion of the first feed gear, and a second gear portion which is always in engagement with the spur gear of the feeding motor; Gears; A third transfer gear axially supported on the feed shaft, the third feed gear being always meshed with the spur gear of the feeding motor, the gear portion being selectively engaged with the second gear portion of the first transfer gear; Switching means for slidingly conveying the feed shaft in the feed direction of the pickup unit so that the first and second gear portions of the first transfer gear and the first gear portion and the gear portion of the third transfer gear of the second transfer gear are selectively engaged with each other. ; It is characterized by that including the.

According to one preferred aspect of the present invention, the switching means includes a feed lever pivotally supported at a center thereof on the base, the feed lever being coupled to the feed shaft; A solenoid positioned on a base adjacent to the transfer lever, the rod being coupled to the other end of the transfer lever to rotate the transfer lever clockwise and counterclockwise; It is in including.

1 is a schematic perspective view of a conventional pickup unit feeding device.

2 is a schematic plan view of a pickup unit feeding device of an optical disc player according to the present invention;

3 is a perspective view of the main portion excerpt.

4 is a plan view showing an operating state of the present invention.

* Description of the symbols for the main parts of the drawings *

10: Base 11: Feed Screw

20: pickup unit 30: feeding motor

31: spur gear 40, 60, 70: 1st, 2nd, 3rd transfer gear

50: feed shaft 80: switching means

81: feed lever 82: solenoid

Such a characteristic configuration and effects of the present invention will become more apparent from the following detailed description of the invention with reference to the accompanying drawings.

Fig. 2 is a schematic plan view of a pickup unit feeding device of an optical disc player according to the present invention, and Fig. 3 is a perspective view showing main parts. 4 is a plan view showing an operating state of the present invention.

As shown therein, the pickup unit feeding apparatus of the optical disc player according to the present invention is roughly divided into a base 10, a pickup unit 20, a feeding motor 30, and a speed displacement means.

One end of the pickup unit 20 is slidably supported on the base 10, and the other end thereof is fastened to the feed screw 11 so that the radial direction of the optical disk is caused by the rotation of the feed screw 11. It is installed to be slidable.

The feeding motor 30 is located on the base 10 adjacent to the pickup unit 20, and the spur gear 31 is axially supported and rotated within a predetermined length on the rotation axis thereof.

On the other hand, the speed displacement means for simplifying the servo circuit by obtaining a variable speed displacement has substantially the characteristic elements of the present invention. Since the transfer gear 40 is axially supported, the first transfer gear 40 has a relatively small number of teeth with the first gear portion 41 having a relatively large number of teeth relative to the end of the transfer screw 11. The second gear part 42 is provided.

At this time, the feed shaft 50 is positioned between the feed screw 11 and the feeding motor 30, in particular, the feed shaft 50 is in the same direction as the pickup unit 20 on the base 10, that is, the optical disk ( Slidably installed in the radial direction of the (not shown).

Meanwhile, the second and third transfer gears 60 and 70 are sequentially press-fitted on the outer circumferential surface of the feed shaft 50, and the first gear portion of the first transfer gear 40 is formed on the second transfer gear 60. 41) and a first gear portion 61, which is selectively engaged with the spur gear 31 of the feeding motor 30, and a second gear portion 62, which is always engaged with the spur gear 31 of the feeding motor 30. In addition, the third transfer gear 70 is always meshed with the spur gear 31 of the feeding motor 30, and the gear portion that is selectively engaged with the second gear portion 42 of the first transfer gear 40. Has 71.

At this time, on the base 10, the first and second gear portions 41 and 42 of the first transfer gear 40 and the first gear portion 61 and the third transfer gear 70 of the second transfer gear 60 are described. Switching means (80) is provided for slidingly conveying the feed shaft (50) so that the gear portion (71) of the can be selectively engaged.

In the detailed structure of the switching means 80, the center surface of the feed lever 81 is pivotally supported on the base 10 so as to be rotatable, and one end of the feed lever 81 is the feed shaft 50 described above. Is combined with the end of the. The solenoid 82 is positioned on the base 10 adjacent to the transfer lever 81, and the rod 82a end of the solenoid 82 is coupled to the other end of the transfer lever 81. That is, the transfer lever 81 is rotated clockwise and counterclockwise according to the operation of the solenoid 82.

Referring to the operation of the present invention configured as described above is as follows.

First, a state as shown in FIG. 2 is a state where the pickup unit 200 is located on the outer circumferential surface of the optical disc. In this state, the rotational force of the spur gear 31 of the feeding motor 30 is axially supported by the feed screw 11 toward the first gear 1 of the second feed gear 60 engaged therewith. It is transmitted to the first gear portion 41 of the transfer gear 40, the transfer screw 11 is rotated at a relatively small rotational speed.

In this state, when the pickup unit 20 is gradually transferred in the inner circumferential direction of the optical disc, it is necessary to transfer the pickup unit 20 at a relatively high speed. Therefore, when the solenoid 82 is operated at some point, the feed lever 81 having one end coupled to the rod 82a is rotated and at the same time the feed shaft 50 coupled to the other end of the feed lever 81. The sliding transfer is performed so that the second gear portion 42 of the first transfer gear 40 and the gear portion 71 of the third transfer gear 70 are engaged with each other as shown in FIG. 4. Therefore, the rotational force from the spur gear 31 of the feeding motor 30 is transmitted thereto, so that the feed screw 11 is rotated at a relatively high speed, and as a result, the pick-up unit 20 is driven at a high speed. Sliding in the inner circumferential direction.

On the other hand, in the case where the pickup unit is slid to the outer circumferential direction in the inner circumferential direction of the optical disk, the pickup unit 20 is conveyed at a variable speed by an operation opposite to the transfer in the inner circumferential direction described above.

As described above, according to the pickup unit feeding device of the optical disc player according to the present invention, the configuration of the servo circuit is simplified by changing the rotational speed of the feed screw by varying the feed speed of the pickup unit on the inner and outer circumference of the optical disc. In particular, there is an effect that stable recording / reproducing can be performed even in a high speed mechanism such as a CD-ROM.

Claims (2)

One end of which is slidably supported on the base and the other end of which is a pickup unit fastened to the transfer screw, and a feeder in which a spur gear of a predetermined length is axially supported on the rotational axis and positioned on a base adjacent to the pickup unit. Pick-up of an optical disc player, located between the feeding motor and the pick-up unit, and including speed displacement means for variably transmitting the power from the feeding motor onto the feed screw to vary the rotational speed of the feed screw. In the unit feeding device, The speed shift means is press-installed at the end of the transfer screw 11, the first gear portion 41 with a large number of teeth relative to the end of the transfer screw 11 and the second gear portion with fewer teeth. A first transfer gear 40 provided with a 42; A feed shaft (50) positioned between the feeding motor (30) and the feed screw (11) and slidably installed on the base (10) in a sliding feed direction of the pickup unit (20); The first gear portion 61 and the feeding motor 30 are axially supported on the outer circumferential surface of the feed shaft 50 and selectively engaged with the first gear portion 41 of the first transfer gear 40. A second transfer gear (60) having a second gear portion (62) which is always engaged with the spur gear (31); It is axially supported on the feed shaft 50, and is always meshed with the spur gear 31 of the feeding motor 30, and selectively with the second gear portion 42 of the first transfer gear 40. A third transfer gear 70 having the gear portion 71 engaged therewith; Gear parts 71 of the first and second gear parts 41 and 42 of the first transfer gear 40 and the first gear part 61 and the third transfer gear 70 of the second transfer gear 60. Switching means (80) for slidingly conveying the conveying shaft (50) in the conveying direction of the pickup unit (20) so that the c) is selectively engaged; Pick-up unit feeding device of an optical disc player, characterized in that it comprises a. The method of claim 1, The switching means (80) includes a feed lever (81) whose central plane is pivotally supported on the base (10), one end of which is coupled to the feed shaft (50); Located on the base 10 adjacent to the transfer lever 81, the rod 82a is coupled to the other end of the transfer lever 81 to rotate the transfer lever 81 clockwise and counterclockwise Solenoid 82; Pickup unit feeding device of the optical disk player, including.