This application claims the benefit of Korean Patent Application No. 2005-93961, filed Oct. 6, 2005 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.
1. Field of the Invention
Aspects of the present invention relate to an optical pickup apparatus, a method of controlling the same, and a method of releasing a locking state thereof, and more particularly, to an optical pickup apparatus, which alternately repeats regular and reverse rotations of a feeding motor to release a locking state thereof, a method of controlling the same, and a method of releasing the locking state thereof.
2. Description of the Related Art
Generally, an optical disk player comprises a spindle motor for rotating a disk, an optical pickup unit for recording data on the rotating disk or reading data from the disk, and a feeding unit for performing an operation for feeding the optical pickup apparatus in the radial direction of the disk (i.e., for performing a feeding operation).
Korean Patent Laid-open Publication No. 2004-18015 discloses a feeding unit. As disclosed, the feeding unit comprises a lead screw having a spiral groove formed therein, a driving motor for rotating the lead screw, and a power transmission gear for converting the rotating motion of the lead screw into a rectilinear reciprocating motion and transmitting the rectilinear reciprocating motion to the optical pickup apparatus. The power transmission gear comprises a slider having contact portions engaged with the spiral groove of the lead screw, and an elastic member for elastically supporting the slider towards the lead screw so that the slider elastically contacts the spiral groove. The feeding unit serves to reciprocate the optical pickup apparatus from the innermost circumference of a lead-in region of the disk to the outermost circumference of a lead-out region of the disk. The feeding unit using the lead screw and the slider has advantages, such as accuracy of feeding and prevention of backlash. However, when an external impact or excessive load is applied to the feeding unit, a locking state occurs in which the contact portions of the slider deviate from the spiral groove of the lead screw. Thereby, the feeding unit malfunctions.
When a power supply is turned on (S310), it is determined whether or not an optical disk exists using an optical pickup unit (S320). When it is determined that the optical disk exists, the optical pickup unit moves to the innermost circumference of the optical disk (S330), and then moves to a position of the optical disk in which initial data are stored (S340). When the feeding unit is in a normal state, the optical pickup apparatus is able to obtain the initial data (S350) and reads the initial data of the disk and performs recording and reproducing operations of the optical disk (S390). However, when the feeding unit is in a locking state, since the feeding unit cannot move the optical pickup unit by normal power, the optical pickup unit cannot move to the position of the optical disk in which the initial data are stored and thus cannot obtain the initial data of the optical disk (S350).
When it is impossible to read the initial data of the optical disk even after several tries, the optical pickup apparatus is operated in an emergency mode (S360˜S380). In the emergency mode, a motor is rotated under the condition that the power of the motor is increased (S360), and the optical pickup unit is moved in a direction towards the inner circumference of the optical disk (S360˜S380).
However, when the optical pickup unit moves in the direction towards the inner circumference of the optical disk, the optical pickup unit collides with the innermost circumference, thereby generating noise. Further, since the impact is applied to the optical pickup unit, the impact causes a difficulty in reading the initial data of the optical disk. Also, when the lead screw is continuously rotated under the condition that the optical pickup unit located at the innermost circumference of the optical disk cannot move any more, teeth of the slider 22 contacting the contact portions 32c are damaged.
Aspects of the invention provide a method of releasing a locking state of an optical pickup apparatus without generating impact to an optical pickup unit and a feeding unit.
Aspects of the invention provide an optical pickup apparatus, which minimizes a time taken to obtain initial data of an optical disk, and a method of controlling the same.
In accordance with an aspect of the present invention, a method of releasing a locking state of an optical pickup apparatus having a feeding unit having a feeding motor, a lead screw rotated by the feeding motor and provided with a spiral groove formed in the outer circumferential surface thereof, and a slider for converting the rotating motion of the lead screw into a rectilinear reciprocating motion and transmitting the rectilinear reciprocating motion to a pickup unit, comprises: alternately repeating regular and reverse rotations of the lead screw so as to release the locking state in which contact portions of the slider are deviated from the spiral groove of the lead screw.
According to an aspect of the invention, the regular and reverse rotations of the lead screw are alternately repeated and are performed at the maximum output of the feeding motor for rotating the lead screw.
According to an aspect of the invention, the regular and reverse rotations of the lead screw are alternately repeated and are performed three times.
According to an aspect of the invention, the regular and reverse rotations of the lead screw are alternately repeated and are performed such that moving distances of the pickup unit are gradually decreased.
In accordance with one aspect of the present invention, a method of controlling an optical pickup apparatus having a feeding unit having a feeding motor, a lead screw rotated by the feeding motor and provided with a spiral groove formed in the outer circumferential surface thereof, and a slider for converting the rotating motion of the lead screw into a rectilinear reciprocating motion and transmitting the rectilinear reciprocating motion to a pickup unit, comprises: performing a locking-releasing operation for releasing a locking state in which contact portions of the slider are deviated from the spiral groove of the lead screw when power is applied to the optical pickup apparatus.
According to an aspect of the invention, the locking-releasing operation is performed by alternately repeating regular and reverse rotations of the lead screw.
According to an aspect of the invention, the regular and reverse rotations of the lead screw are alternately repeated and are performed at the maximum output of the feeding motor for rotating the lead screw.
According to an aspect of the invention, the regular and reverse rotations of the lead screw are alternately repeated and are performed three times.
According to an aspect of the invention, the regular and reverse rotations of the lead screw are alternately repeated and are performed such that moving distances of the pickup unit are gradually decreased.
In accordance with another aspect of the present invention, an optical pickup apparatus comprises: a feeding unit having a feeding motor, a lead screw rotated by the feeding motor and provided with a spiral groove formed in the outer circumferential surface thereof, and a slider for converting the rotating motion of the lead screw into a rectilinear reciprocating motion and transmitting the rectilinear reciprocating motion to a pickup unit; and a control unit for controlling the feeding motor so that regular and reverse rotations of the lead screw are alternately repeated so as to release a locking state in which contact portions of the slider are deviated from the spiral groove of the lead screw.
According to an aspect of the invention, the control unit controls the feeding motor so that the regular and reverse rotations of the lead screw, which are alternately repeated, are performed at the maximum output of the feeding motor for rotating the lead screw.
According to an aspect of the invention, the control unit controls the feeding motor so that the regular and reverse rotations of the lead screw, which are alternately repeated, are performed three times.
According to an aspect of the invention, the control unit controls the feeding motor so that the regular and reverse rotations of the lead screw, which are alternately repeated, are performed such that moving distances of the pickup unit are gradually decreased.
These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings in which:
Reference will now be made in detail to the embodiments of the present invention, an example of which is illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. The embodiments are described below to explain the present invention by referring to the annexed drawings.
A feeding unit 20 for reciprocating the pickup unit 12 in the radial direction of the disk is installed at one side of the pickup unit 12. The feeding unit 20 comprises a feeding motor 21, the lead screw 22 rotated by the feeding motor 21, and a slider 30 for converting the rotating motion of the lead screw 22 into a rectilinear reciprocating motion and transmitting the rectilinear reciprocating motion to the pickup unit 12. The feeding motor 21 is fixed to the base chassis 10. The lead screw 22 is disposed in parallel with the guide shafts 13, and a spiral groove 22a is formed in the outer circumferential surface of the lead screw 22. A control unit 50 controls an overall operation of the optical disk player to record and/or reproduce data with respect to a recording medium (not shown), and controls a motor driving unit 40 to drive the spindle motor 11 and the feeding motor 21.
Hereinafter, with reference to
In a normal state, as shown in
With reference to
After the feeding unit 20 is returned to its normal state through the locking-releasing operation of operation S410, the optical disk player performs a basic operation for obtaining initial data of the optical disk (S430˜S450). That is, the control unit 50 drives the motor driving unit 40 to drive the feeding motor 21 at normal power for a designated time so that the optical pickup unit 12 moves to the innermost circumference of the optical disk (S430). Whether or not the optical pickup unit 12 moves to the innermost circumference of the optical disk is determined by several known methods, such as using a limit switch and driving a motor so that the optical pickup unit 12 moves to a designated distance from the assumed initial position thereof. When the optical pickup unit 12 moves to the innermost circumference of the optical disk, the feeding motor 21 is rotated in a direction towards the outer circumference of the optical disk so that the optical pickup unit 12 moves to a designated position of the optical disk so as to obtain the initial data of the optical disk (S440). The rotating direction of the feeding motor 21 for moving the optical pickup unit 12 towards the outer circumference of the optical disk is opposite to the rotating direction of the feeding motor 21 for moving the optical pickup unit 12 towards the inner circumference of the optical disk. Generally, the feeding motor 21 is rotated in the counterclockwise direction (CCW) so as to move the optical pickup unit 12 towards the outer circumference of the optical disk, and is rotated in the clockwise direction (CW) so as to move the optical pickup unit 12 towards the inner circumference of the optical disk. Thereafter, the optical disk player reads the initial data of the optical disk, and then performs reproducing and recording operations of the optical disk (S450). While not required in all aspects, the optical disk player can further utilize an emergency mode, such as the emergency mode (S360˜S380) shown in
After the optical pickup unit moves to the designated moving distance (n) in the direction towards the outer circumference of the optical disk, the optical pickup unit moves again to a distance, shorter than the moving distance (n), in the direction towards the inner circumference of the optical disk. The gradual decrease of the moving distances of the optical pickup unit reduces or prevents noise, which is generated when the optical pickup unit is located at the innermost or outermost circumference of the optical disk. That is, since the optical pickup unit moves in the direction towards the inner circumference of the optical distance to a distance shorter than the moving distance of the optical pickup unit in the direction towards the outer circumference of the optical disk, although the optical pickup unit is initially located at the innermost circumference, noise due to the movement of the optical pickup unit in the direction towards the inner circumference is not generated (S520).
Finally, the optical pickup unit moves again to a distance, shorter than the moving distance in operation S520, in the direction towards the outer circumference of the optical disk (S530). While described as starting in a particular direction, it is understood that the starting direction and/or rotational directions for the reversals in S510 through S530 can be otherwise. Moreover, it is understood that other patterns of counter rotations can be used at varying speeds and directions. Additionally, while the disclosed example counter-rotation pattern has each rotation being in an opposite direction from the preceding rotation, it is understood that the pattern could have consecutive same direction rotations having various speeds and/or distances n prior to or after an opposite direction rotation.
As described above, the optical pickup apparatus according to aspects of the present invention more efficiently releases its locking state through alternate repetitions of regular and reverse rotations of the feeding motor, and prevents generation of noise and abrasion of the contact portions 32c of the slider 30 through the movement of the optical pickup unit to gradually shorter distances.
As is apparent from the above description, aspects of the present invention provide an optical pick up apparatus, which efficiently releases its locking state through alternate repetitions of regular and reverse rotations of a feeding motor, a method of controlling the same, and a method of releasing the locking state thereof.
While not required, it is understood that aspects of the invention can be implemented as computer readable software and/or firmware implemented by a processor (such as the control unit 50). Additionally, it is understood that the optical disk player can be a reproducing apparatus and/or a recording apparatus, and can be included in a computer or as a stand alone audio and/or video component. Also, while described as used in the context of the optical pickup apparatus, it is understood that aspects of the invention can be used for other apparatuses using screws to drive an element along guide rails, and/or in apparatuses usable with non-optical and magneto-optical recording media.
Further, the optical pickup apparatus of aspects of the present invention first perform a locking-releasing operation when power is applied to the optical pickup apparatus, thereby shortening a driving time thereof.
Moreover, since moving distances of an optical pickup unit of the optical pickup apparatus of aspects of the present invention are gradually decreased when the regular and reverse rotations of the feeding motor are alternately repeated, it is possible to prevent generation of noise and damage to a slider and the optical pickup unit.
Although embodiments of the invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.
Number | Date | Country | Kind |
---|---|---|---|
2005-93961 | Oct 2005 | KR | national |