Abstract
The paper studies the characterization and evaluation technology of rotation accuracy of hydrostatic spindle under the influence of unbalance. The dynamic model of the motion error of the hydrostatic spindle is established based on the dynamic parameters. The variation law of motion error of spindle rotor is analyzed under the unbalanced mass. The paper finds that with the increase of the spindle speed, the amplitude of the spindle error motion will increase, and the inclination angleθerror is more sensitive to the change in the rotational speed. In the total synthesis accuracy, the proportion of synchronization error decreases with the increase of the rotational speed. Finally, the least squares evaluation algorithm is used to evaluate the rotation error of the hydrostatic spindle, and a method for evaluating the rotation accuracy of the hydrostatic spindle with high calculation accuracy and calculation efficiency is proposed.
Highlights
IntroductionThe motion error of the hydrostatic spindle has a significant effect on the machining accuracy. e imbalance of the spindle is the main factor affecting the spindle motion error. e motion will be affected by various unbalanced disturbances during the operation of the spindle; i.e., the geometric error of the shaft and bearing will cause the imbalance in the high rotation speed condition, the unbalanced dynamic load caused by the eccentric mass of the spindle rotor, the defect of the spindle component, and the cutting force during the cutting process. e rotor will generate motion error under the disturbance of single unbalanced dynamic load or composite dynamic load. e analysis of the motion error of the spindle can evaluate and analyze the dynamic and steady state performance of the spindle system under dynamic load disturbance
In order to be able to further analyze the motion error of the spindle, it is necessary to analyze the synchronization error and the asynchronous error of the spindle. e synchronization error is part of the total error motion, which occurs at an integer multiple of the spindle rotation frequency
It is the average contour of the polar plot of the total error motion obtained by averaging the number of revolutions. e synchronization error is related to periodic excitation factors such as dynamic imbalance associated with spindle frequency. e asynchronous error is part of the total error motion, which does not appear at integer multiples of the same rotation frequency. e asynchronous error corresponds to the noninteger multiplication component of the spindle speed. e asynchronous error is mainly related to the random interference factor, such as the pulsation of the oil supply pressure and random vibration. e total synthesis precision is the nonlinear sum of the synchronous precision and the asynchronous precision
Summary
The motion error of the hydrostatic spindle has a significant effect on the machining accuracy. e imbalance of the spindle is the main factor affecting the spindle motion error. e motion will be affected by various unbalanced disturbances during the operation of the spindle; i.e., the geometric error of the shaft and bearing will cause the imbalance in the high rotation speed condition, the unbalanced dynamic load caused by the eccentric mass of the spindle rotor, the defect of the spindle component, and the cutting force during the cutting process. e rotor will generate motion error under the disturbance of single unbalanced dynamic load or composite dynamic load. e analysis of the motion error of the spindle can evaluate and analyze the dynamic and steady state performance of the spindle system under dynamic load disturbance. Anandan and Ozdoganlar [8] presented a method based on the laser Doppler vibration method for measuring axial and radial error motion when using a micro ultrahigh speed (UHS) spindle in micromachining applications. Shock and Vibration proposed a method for measuring the radial motion error of the spindle. Fu et al [20] proposed a new method for measuring the rotation error of ultraprecision aerostatic spindle based on interference fringes. Oil recess length L1 (mm) Axial sealing edge c1 (mm) Circumferential sealing edge b1 (mm) Length factor of radial sealing surface w Effective bearing area Ab (m2) Dynamic viscosity of lubricating oil μ (kg/ms).
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
