| In the revolving machine, the eccentric mass which caused by the installment errors or rotor part's manufacture precision will make the revolving machine vibrating, which may influence machine stabilization and part attrition. So the dynamic balanced examination and control is applied to rotor for reducing vibration. However, the revolving machine have to run and stop off several times to do it by using the majority dynamic balance methods, which disturbs equipment's work. Along with the technical development, the require of production efficiency and the precision is unceasingly raising. The online dynamic balance examination and the control system without stopping machine has become one of hot focus in the dynamic balance domain.After researching present online dynamic balance methods, a online dynamic balance equipment is designed that detects the eccentric mass quality and position only with one sensor using parallelogram principle in the rolling disk system of the hard disk driver (HDD). This equipment controls the eccentric mass by grinding, which simplifies equipment and avoids of many components, complex structure, difficult control and so on.In order to raise the balanced efficiency and avoid destroying the rotor, the pre-fastness easily grinding block is placed in disk to be grinded for controlling eccentric mass. The block and wheelhead are selected through contrasting different materials. It raises grinding speed and reduces grinding vibration.In order to realize the automatic dynamic balance, the equipment uses single chip micyoco (SCM) to sample and analysis the sensor's vibration signal and control step motor to feed wheelhead for removing the eccentric mass.Experiments of the online dynamic balance equipment are carried out in the end of this paper. The experiments include: 1. The outside noise disturbs the unbalance signal's extraction. By contrasting the vibration isolation effect of several materials one of them is used to reduce the outside vibration disturbance. 2. Comparing the signals of sensor in different distance to HDD, the best location of sensor is found where signal to noise ratio is efficiently increased. 3. The experiment is carried out to balance HDD rolling disk system using online dynamic balance. Finally, the remains of vibration is 195mg·mm that approaches the minimum vibration 132mg·mm, which indicates that the online dynamic balance equipment could reduce HDD's vibration effectively. |
