Optical disk drive

An optical disk drive including a sliding portion, which moves a sub frame upward or downward against a main frame; a sensor, which includes tension members which are provided in both sides of the sliding portion so that the tension members are elastically deformed to apply an additional load to the sliding portion when the sliding portion slides, and stopper members which contact the tension members and elastically deform the tension members when the sliding portion slides; and a controller, which senses a current change of a driving motor when the additional load is applied to the sliding portion, recognizes whether the tray is loaded or unloaded onto or from the main frame, and controls the driving motor.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority of Korean Patent Application No. 2003-58291, filed on Aug. 22, 2003, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an optical disk drive, and, more particularly, to a sensor that senses whether a tray is loaded or unloaded onto or from a main frame.

2. Description of the Related Art

Generally, optical disk drives such as CD-ROM or DVDP are devices to recordor read information onto or from an optical disk.

FIG. 1is an exploded perspective view showing a structure of a conventional optical disk drive,FIG. 2is a perspective view showing a main frame shown inFIG. 1, andFIG. 3is a side view of a sliding portion as viewed in the direction of an arrow ofFIG. 2.

Referring toFIG. 1, the optical disk drive100includes a main frame110, a tray120, a sub frame130, and a base chassis140. The tray120is insertable into the main frame110, includes a first resting portion121on which a 120 mm disk (not shown) is rested and a second resting portion122on which a 80 mm disk is rested, and delivers the rested disks into the main frame110. The sub frame130is movably mounted in the main frame110. The sub frame130supports the base chassis10.

The base chassis140includes a turn table141on which an optical disk, which is rested on the tray120which is transferred into the main frame110, is rested, a spindle motor (not shown) which is placed on the same axis as the turn table141and rotates the turn table141, and an optical pickup device142which records information on the optical disk or reproduces information recorded on the optical disk while sliding in a radial direction of the optical disk rested on the turn table141.

Referring toFIGS. 2 and 3, the main frame110includes a sliding portion112, which slides in a state of being coupled with a driving device111in a direction which is perpendicular to the direction in which the tray120is inserted into the main body. The sliding portion112has two cam slots115(seeFIG. 3). While a plurality of cam projections131, formed on the sub frame130(seeFIG. 1), slide according to the tracks of the cam slots115, the sub frame130is rotated upward and downward while remaining centered on a rotation axis132supported by the main frame110.

Also, the main frame110includes two switches113connected to a micom (not shown). The switches113recognize operations of the tray120and the sliding unit112by contacting or being detached to or from two contacts114formed on the sliding portion112and send a recognized signal to the micom (not shown) by which operations of the optical disk drive100are controlled.

In the conventional optical disk drive100with the above-described configuration, since components, each having respective predetermined tolerances, are assembled together, the tolerances create gaps between the respective components.

Particularly, due to gaps created between the respective components by tolerances existing between the sliding portion112, the cam slots115and the cam projections131, the contacts114formed on the sliding portion112cannot stably press the switches113formed on the main frame110when the sliding portion112moves upward and downward against the main frame110, which prevents a smooth operation of the optical disk drive100. That is, the switches113may recognize the operations of the optical disk drive100when they are firmly pressed by the contacts114. However, since the gaps created by the tolerances prevent the switches113from being stably pressed by the contacts114, a problem exists in that the switches113cannot correctly recognize the operations of the optical disk drive100.

SUMMARY OF THE INVENTION

The present invention provides an optical disk drive including a sensor to recognize whether a tray is loaded or unloaded onto or from a main frame by detecting a current change of a driving motor.

According to an aspect of the present invention, an optical disk drive comprises a sliding portion, which is mounted in a main frame to slide on the main frame and move a sub frame upward or downward against the main frame when a tray is loaded or unloaded onto or from the main frame; a sensor, which includes tension members which are provided in both sides of the sliding portion so that the tension members are elastically deformed to apply an additional load to the sliding portion when the sliding portion slides, and stopper members which contact the tension members and elastically deform the tension members when the sliding portion slides; and a controller, which senses a current change of a driving motor when the additional load is applied to the sliding portion, and which recognizes whether the tray is loaded or unloaded onto or from the main frame, and controls the driving motor.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring toFIGS. 4 and 5, an optical disk drive200comprises a main frame210, a tray220, a sub frame230, a base chassis240, and a sliding portion212. The tray220includes a first resting portion221which is insertable into the main frame210and on which a 120 mm disk (not shown) is rested and a second resting portion222on which a 80 mm disk is rested, and delivers the rested disks to the main frame210. The sub frame230is movably mounted in the main frame210. The sub frame230supports the base chassis240. A driving motor211drives the sliding portion212in a manner such that the sliding portion212is slid on the main frame210. The sliding portion212slides in a direction that is perpendicular to the direction of the insertion of the tray220into the main frame210. The driving motor additionally causes the sub frame230to rotate against the main frame210.

The base chassis240includes a turn table241on which a disk, rested on the tray220and delivered into the main frame210, is rested after delivery into the main frame210. The base chassis240also includes a spindle motor (not shown) which is placed on the same axis as the turn table241to rotate the turn table241. The base chassis240additionally includes an optical pickup device242which either records information on the disk or reproduces information recorded on the disk while sliding in a radial direction of the disk rested on the turn table241.

A plurality of cam slots (not shown) are formed in the sliding portion212. Cam projections231formed on the sub frame230slide according to the tracks of the cam slots, so that the sub frame230moves upward or downward while remaining centered on a rotation axis232supported by the main frame210.

Tension members213are provided in both sides of the sliding portion212to project from the sliding portion212. Alternately, the tension members213may be integrated with the sliding portion. An additional aspect of the tension members213is that they may have various shapes in addition to the illustrated cylindrical shape (seeFIG. 5). The tension members213are elastically deformable so as to apply an additional load to the sliding portion212when the sliding portion212slides.

Also, stopper members214(seeFIG. 4) are formed in the main frame210to be projected on a path on which the sliding portion212slides. In an embodiment of the invention, the stopper members214are block shaped, although, like the tension members213, the stopper members214may take on various shapes. As a result of this configuration, while the sliding portion212slides, the portions of the stopper members214that contact the tension members213elastically deform the tension members213.

The tension members213are preferably elastically deformed in an opposite direction of a direction in which the sliding portion212slides.

A controller250is connected to the driving motor211. The controller250senses a current change of the driving motor211caused by an additional load applied to the sliding portion220through the tension members213, when the tray220is loaded or unloaded onto or from the main frame210, to thereby recognize whether the tray220is loaded or unloaded onto or from the main frame210and control the driving motor211.

Hereinafter, how the controller senses whether the tray is loaded or unloaded onto or from the main frame will be described with reference to the appended drawings.

Referring toFIGS. 4 through 6, when the driving motor211is rotated forward, the tray220is loaded on the main frame210. The sliding portion212slides in a direction of an arrow A as shown inFIG. 5. At this time, a current value applied to the driving motor211is uniform as illustrated inFIG. 6.

Referring toFIG. 6, at the time when the tray220is loaded on the main frame210, the tension members213contact the stopper members214to move from the location of the solid line to the location of the dotted line (SeeFIG. 5), so that an additional load is applied to the sliding portion212. At this time, a current value applied to the driving motor211increases by a value of C as illustrated inFIG. 6.

The additional load applied to the driving motor211causes the increase of the current value of the driving motor211. Such an increased current value indicates that the tray220is completely loaded on the main frame210.

Accordingly, the controller250recognizes that the tray220is completely loaded on the main frame210when the current value of the driving motor211abruptly increases, after a predetermined time is elapsed from a time when the tray220is loaded on the main frame210.

If a time interval from a time when the tray220is loaded on the main frame210to a time when the current value of the driving motor211increases is smaller than the predetermined time, the controller250recognizes that an abnormal load is generated in the state where the tray220is not completely loaded on the main frame210. The controller250then controls the driving motor211so as to correct for the abnormal load.

On the contrary, when the driving motor211is rotated, for example, backward, the tray220is unloaded from the main frame210. The sliding portion212slides in a direction of an arrow B as shown inFIG. 5. At this time, a current value applied to the driving motor211is uniform as illustrated inFIG. 6.

At the time when the tray220is unloaded from the main frame210, the tension members213contact the stopper members214to move from the location of the solid line to the location of the dotted line (seeFIG. 5) so that an additional load is applied to the sliding portion212. At this time, the current value applied to the driving motor211increases by a value of D as shown inFIG. 6.

The additional load applied to the driving motor211causes the increase of the current value of the driving motor211. Such an increased current value indicates that the tray220is completely unloaded from the main frame210.

Accordingly, the controller250recognizes that the tray220is completely unloaded from the main frame210when the current value of the driving motor211abruptly increases after a predetermined time is elapsed from a time when the tray220is unloaded from the main frame210.

If a time interval from a time when the tray220is unloaded from the main frame210to a time when the current value of the driving motor211increases is smaller than the predetermined time, the controller250recognizes that an abnormal load is generated in the state where the tray220is not completely unloaded from the main frame210. The controller25then controls the driving motor211to be deviated from the abnormal load.

As is described above, according to the optical disk drive of the present invention, it is possible to simplify the structures of components as well as to prevent a touch-sensitive sensor from performing an error in operation due to its tolerances.