KR19980058825A - Optical disc player - Google Patents

Abstract

The present invention discloses an optical disc player.

The present invention is a base having a turntable rotationally driven by a spindle motor on one side thereof, one end of which is slidably supported on the base, and the other end of which is fastened to a feed screw, so that the feed motor An optical disc player comprising a pick-up unit that is radially slidably transported, wherein the turntable, which is rotationally driven by the spindle motor, varies in speed depending on the sliding transport position of the pickup via the clutch means, By transporting the unit at a constant speed and by varying the rotational speed of the turntable via the clutch means, it is possible to stably reproduce the optical disc. That is, not only has the advantage of simplifying the servo circuit through a simple mechanical configuration, but also has the effect of making stable recording / reproducing even in a high speed mechanism such as a CD ROM.

Description

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 an optical disk player capable of stably reproducing an optical disk by varying a rotational speed of a turn table for rotating the 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 therefrom, 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 the optical disk is mounted on the turn table 1 which is rotationally driven by the spindle motor (not shown), and the pickup unit reads recordings from the optical disk about the optical disk, that is, in the radial direction of the optical disk. (2) is slidingly conveyed by the feeding apparatus.

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.

In the structure of the feeding means, on the main chassis (not shown) adjacent to the turn table, a feeding motor M is provided on which a gear 4 is fixed on its rotation axis, and the gear is located at a 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) ) Slides along the transfer screw 6, i.e., in the radial direction of the optical disc, to perform recording / reproducing.

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

Such servo control cannot be performed very precisely. In general, the signal format of the disc adopts a method (CLV method) which has a constant linear velocity in the inner and outer periphery. The amount of data read 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, to obtain a variable deceleration ratio, but it is variable through the engagement between a plurality of gears 4 and 5 as in the prior art. It is difficult to obtain the deceleration ratio and therefore it is not easy to perform the servo control very precisely. In addition, in order to solve such a problem, the control circuits have to be very complicated with each other, so there is a difficult design.

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

SUMMARY OF THE INVENTION The present invention has been made to solve all the problems of the conventional pickup unit feeding apparatus, and provides an optical disc player that can accurately read signals even from a disk rotating at high speed, and in particular, can simplify the servo circuit. There is this.

In order to achieve the above object, an optical disc player according to the present invention includes a base having a turntable on which one side is rotated and driven by a spindle motor, and one end of which is slidably supported on the base. An optical disc player comprising a pickup unit fastened to a feeding screw and slidingly conveyed in a radial direction of an optical disk by a feeding motor, wherein the turntable driven by the spindle motor is a sliding conveyance position of the pickup via clutch means. The speed is variable according to the characteristics.

1 is a schematic plan 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 sectional view of the main parts.

<Description of the code | symbol about the principal part of drawing>

10: base 20: spindle motor

30: turn table 40: pickup unit

70: switching ring 71: gear

80: one-way spring 90: switching means

91: switching lever 91a: rack gear

91b: Pressing protrusion 92: Rotating lever

93: solenoid 94: torsion spring

Such a characteristic configuration and the resulting 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 plan view of the optical disc player according to the present invention, and Fig. 3 is an enlarged sectional view showing main parts.

As shown in the figure, in the optical disc player according to the present invention, a turn table 30 which is rotationally driven by a spindle motor 20 is positioned on a base 10.

In addition, a pick-up unit 40 is positioned on the base 10, and one end of the pick-up unit 40 is slidably supported on the base 10, and the other end thereof is a feeding motor. And coupled to a feeding screw 60 which is engaged with and rotated to the final gear g of the plurality of gear groups G rotated by 50, and is seated on the turntable 30 by its rotation. Sliding is transported in the radial direction of the optical disk.

On the other hand, the above-described turn table 30 is variable depending on the conveying direction of the pickup unit 40, that is, the rotational speed is variable, i.e. (加減) is.

In this way, the detailed structure of the clutch means for adjusting the rotational speed of the turn table 30 is largely divided into a switching ring 70, a one way spring 80, and a switching means 90.

The switching ring 70 is inserted into the lower outer circumferential surface of the turntable 30 in which the inner circumferential surface is pressed into the rotary shaft 21 of the spindle motor 20 so that the inner circumferential surface maintains a predetermined interval. 71 is extended.

On the other hand, the one-way spring 80 is inserted into the gap between the outer circumferential surface of the turn table 30 and the inner circumferential surface of the switching ring 70, in particular one end thereof is the inner side of the switching ring 70 as shown in FIG. It is fixed to the lower surface.

Accordingly, the one-way spring 80 has a directionality having the winding or unwinding around the outer circumferential surface of the turn table 30 according to the rotation direction of the switching ring 70.

At this time, the switching means 90 serves to rotate the switching ring 70 in order to impart the winding property or the loosening property about the outer circumferential surface of the turn table 30 by the one-way spring 80 as described above. .

Looking at the detailed structure of such a switching means 90, on one side of the base 10 is formed a rack gear 91a meshed with the gear 71 of the switching ring 70 on one side thereof, the upper one side The switching lever 91 is formed to be slidable to the pressing projection 91b is extended.

On the other hand, the pivoting lever 92 is pivotally supported on one side surface of the base 10 adjacent to the site where the switching lever 91 is installed, and both ends of the pivoting lever 92 are based on the center of rotation, respectively. As it is formed extending in the V-type, the extended end is in contact with the outer peripheral surface of one side of the pressing protrusion (91b) formed on the switching lever 91 and the other end is a solenoid (solenoid; 93) is coupled. That is, the rotation lever 92 is rotated relative to the center of the shaft according to the operation of the solenoid 93 to press the pressing projection 91b of the switching lever 91 in one direction.

At this time, the rotation lever 92 is inserted into the center of the shaft center of the rotation lever 92, the both ends of the pressing projection (91b) formed in the switching lever 91 and fixed to one side of the base 10 The torsion spring 94 is elastically supported in the direction opposite to the direction in which the solenoid 93 is pressed.

Reference numeral 100 is a limit switch provided on the base 10 to limit the transfer distance of the pickup unit 40 to prevent contact shock between the turntable 30 and the pickup unit 40. .

Referring to the operation of the optical disk player according to the present invention configured as described above are as follows.

First, an example is described in which the optical disk is seated on the turn table 30 and reproduced while being moved from the inner circumferential direction with the pickup unit 40.

The pickup unit 40 is slidably conveyed at a constant speed by the rotation of the feed screw 60 coupled to one side from the inner circumferential direction to the outer circumferential direction of the optical disk seated on the turn table 40.

At this time, the signal format of the optical disk adopts a method of having a constant linear velocity in the inner and outer circumference (CLV method), and the amount of data read from the disk per unit time must always be the same.

To this end, the turntable 30 is rotated at a constant speed by the spindle motor 20 and the feed speed of the pickup unit 40 that is relatively conveyed by the feeding motor 50 is variable, or vice versa of the pickup unit 40. The feed rate is constant and the rotational speed of the turntable 30 should be variable.

In the present invention, the rotation speed of the turn table 30 described later is varied to achieve stable regeneration, and the turn table 30 has a variable speed through clutch means.

In more detail, when the pickup unit 40 is transported at a constant speed from the inner circumference to the outer circumference of the optical disk by the transfer screw 60, the rotation speed of the turntable 30 should be relatively increased gradually. That is, the rotation speed should be slow on the inner circumferential side. To this end, if the solenoid 93 installed on one side of the base 10 is repeatedly operated, the rotating lever 92, one end of which is coupled to the solenoid 93, is also repeatedly rotated to The pressing protrusion 91b extended to one upper portion is repeatedly pressed.

At this time, since the switching lever 91 is elastically supported in a direction opposite to the direction in which the torsion spring 94 is pressed by the rotation lever 92, the switching lever 91 is repeatedly reciprocated along the upper surface of the base 10. When the switching lever 91 is repeatedly reciprocated in this manner, the switching ring 70 having the rack gear 91a formed on one side of the switching lever 91 and the gear 71 engaged therewith is shown in FIG. 2. As it is rotated in a clockwise direction instantaneously, the one-way spring 94, one end of which is coupled to the lower surface of the switching ring 70 has a winding and repeatedly to the outer peripheral surface of the turn table 30 The contact and loosening will be repeated. That is, the brake force is generated when in close contact, and the brake force is released when released.

By this braking force, the rotation speed of the turn table 30 becomes very slow.

When the repetitive operating speed of the solenoid 93 is adjusted in accordance with the access time of the optical disc, that is, the pickup unit 40 is directed toward the outer circumferential side of the optical disc through a microcomputer (not shown). When the operation speed is lowered, the rotational speed of the turntable 30 is gradually increased, and as a result, it is possible to stably reproduce through the pickup unit 40 which is transported at a constant speed.

As described above, according to the optical disc player according to the present invention, it is possible to stably reproduce the optical disc by transferring the pickup unit at a constant speed and conversely by varying the rotational speed of the turntable through the clutch means. That is, not only has the advantage of simplifying the servo circuit through a simple mechanical configuration, but also has the effect of making stable recording / reproducing even in a high speed mechanism such as a CD ROM.

Claims (3)

A base on which a turntable is rotated and driven by a spindle motor is located on one side thereof, and one end thereof is slidably supported on the base, and the other end thereof is fastened to the feed screw to be slid in the radial direction of the optical disk by the feeding motor. An optical disc player comprising a pickup unit to be transported, The turntable (30), which is rotationally driven by the spindle motor (20), varies in speed depending on the sliding conveyance position of the pickup unit (40) via clutch means. 2. The clutch means according to claim 1, further comprising: a switching ring (70) whose inner circumferential surface is inserted so as to maintain a predetermined distance from the lower outer circumferential surface of the turn table (30) and a gear (71) is formed on the lower outer circumferential surface; A one-way spring (80) interposed between the inner circumferential surface of the switching ring (70) and the lower outer circumferential surface of the turn table (30), one end of which is coupled to the switching ring (70); And a switching means 90 for selectively contacting the one-way spring 80 to the outer circumferential surface of the turn table 30 by selectively rotating the switching ring 70 clockwise and counterclockwise. Optical disc player. The rack gear according to claim 2, wherein the switching means (90) is slidably installed on one side of the base (10), and the gear (71) of the switching ring (70) meshes with one side of the base (10). A switching lever 91 formed with an upper surface 91a and an urging protrusion 91b formed on one side thereof; One side of the center is pivotally supported on the base 10 in a rotatable manner, and one end thereof is extended to contact the side surface of the pressing protrusion 91b of the switching lever 91, and the other end thereof is coupled to the solenoid 93. Rotated lever 92; The rotating lever 92 is inserted into the center of the shaft and both ends thereof are engaged with the other outer peripheral surface of the pressing protrusion 91b and one side of the base 10 to rotate the rotating lever 92 by the solenoid 93. And a torsion spring (94) elastically supporting in a direction opposite to the direction in which the optical disk is rotated.