Patent Application
20130099713
1. Field of the Invention
The invention relates to an optical disk drive, and more particularly, to a method for increasing a rotation speed of a spindle motor of the optical disk drive to eliminate vibration and noise.
2. Description of the Prior Art
An optical disk drive uses a spindle motor to rotate an optical disk at high speed, and a pickup head moves along a radial direction of the optical disk to read and write data on the optical disk. A stable rotation of the optical disk can not only increase exactness of reading and writing of the pickup head, but also reduce uncomfortable feelings of users caused by the vibration.
However, the balls are affected by obstruction of friction such as surface roughness, dust, or moisture in the annular track, and the balls may not achieve the optimal position of balance. When the balls has not achieved the optimal position of balance, weight of the balls will make unbalance of the optical disk much more seriously, and cause unbalance rotation to increase vibration and noise. Thus, there still remains a problem of the vibration noise in the prior art.
One objective of the present invention is to provide a method for increasing a rotation speed of a spindle motor to make the rotation speed of the spindle motor to remain at a critical rotation speed to make balls to detach obstruction easily to achieve an optimal position of balance, so as to reduce time of increasing the rotation speed.
Another objective of the present invention is to provide a method for increasing a rotation speed of a spindle motor by increasing the rotation speed of the spindle motor to a predetermined rotation speed, recording a critical rotation speed, decreasing the rotation speed to the critical rotation speed, and increasing the rotation speed to the working rotation speed after remaining at the critical rotation speed for a short time, so as to eliminate vibration noise efficiently.
To achieve the abovementioned objectives, the method for increasing a rotation speed of a spindle motor of the present invention comprises: setting a predetermined rotation speed, wherein the predetermined rotation speed is higher than a critical rotation speed of a resonance frequency and lower than the working rotation speed; increasing the rotation speed of the spindle motor directly over the critical rotation speed to the predetermined rotation speed; recording the critical rotation speed of the spindle motor; decreasing the rotation speed of the spindle motor to the critical rotation speed; remaining at the critical rotation speed for a predetermined short time; and increasing the rotation speed of the spindle motor to a working rotation speed to eliminate vibration noise.
These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.
In order to achieve the abovementioned objectives of the present invention, the adopted technical means and effects are described below by illustrating embodiments with drawings.
Please refer to
The rotation speed of the spindle motor 10 is decreased until reaching the critical rotation speed ωc at time t3, and the rotation speed of the spindle motor 10 is remained at the critical rotation speed ωc initial time t4. During a short time between time t3 and time t4, since the critical rotation speed ωc makes the vibration more fierce, the balls 12 affected by friction such as surface roughness, dust, or moisture in the annular track 11 can detach obstruction easily to achieve an optimal position of balance. Although the critical rotation speed ωc makes the vibration more fierce, the balls 12 can achieve the optimal position of balance quickly, and not only the vibration time is relatively short, but it also can ensure the stable rotating status of the spindle motor 10. Next, the rotation speed of the spindle motor 10 is increased to a working rotation speed ω at time t5, so as to eliminate vibration noise.
In a practical test of the present invention, the rotation speed of the spindle motor 10 is increased to 6000 rpm, which is directly over the resonance frequency 2750 rpm of the optical disk drive, and then decreases the rotation speed of the spindle motor 10 to the resonance frequency 2750 rpm of the optical disk drive, and increases the rotation speed of the spindle motor 10 to the working rotation speed 9600 rpm after remaining at the resonance frequency 2750 rpm for a short time.
Therefore, the method for increasing a rotation speed of a spindle motor of the present invention can utilize increasing the rotation speed of the spindle motor to a predetermined rotation speed, recording a critical rotation speed, decreasing the rotation speed to the critical rotation speed, remaining at the critical rotation speed for a short time to make balls to detach obstruction easily to achieve an optimal position of balance to enter the stable rotating state by using the vibration generated by the critical rotation speed, and increasing the rotation speed to the working rotation speed, so as to eliminate vibration noise efficiently and reduce time of increasing the rotation speed.
Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 100138460 | Oct 2011 | TW | national |
