Views: 0 Author: Site Editor Publish Time: 2023-11-19 Origin: Site
In the process of assembly and commissioning,the vibration generated by the mechanical rotation movement is inevitable,the mechanical vibration will cause harm to the normal use of the machine tool,when abnormal vibration occurs,measures must be taken to ensure the operation of the machine.In addition to the system electrical parameter settings and selection are inappropriate and other factors,there are some mechanical reasons,mainly in the following aspects:
●Ball screw installation factors
The ball screw transmission structure is mainly composed of the ball screw,nut,ball screw seat(also called the bearing seat),bearing,locking nut,coupling,servo motor and so on.In the installation process,it is necessary to ensure that the ball screw axis line is parallel to the reference surface of the moving guide rail. If the installation error is large,the drag plate will bend and deform the ball screw during the movement,and the screw rotation force is not uniform,and then thevibration phenomenon will occur.
●Ball screw nut and drag plate connection installation factors
During the installation process of the screw nut and the drag plate connection,sometimes due to the end processing of the drag plate,the screw hole on the screw nut and the mounting hole on the combination surface of the drag plate interfere with each other,or the mounting surface is not perpendicular to the reference(guide rail)surface,that is,the mounting surface is not parallel to the combination surface of the screw nut,resulting in the screw nut fastening screw being tightened to force the screw to deform. Vibration occurs.
●Coupling installation factors
Motor drive screw rotation is connected through the elastic coupling,in this part of the installation process,first of all to ensure that the screw end of the radial runout error in line with the design requirements,ollowed by to ensure that the motor mounting surface and the screw axis line vertical,the motor rotation axis line and the screw axis line overlap,generally by the design requirements of the positioning hole to ensure.Finally,evenly tighten the fastening screw of the expanded sleeve gland on the coupling with a torque wrench,so that the three conditions are not met,the lead screw and the coupling will vibrate.
●Factors of axial clearance of ball screw
During the movement of the drag plate,if the axial clearance of the lead screw is too large,vibration will also occur,including the drag plate crawling phenomenon.This is because the CNC shaft itself has a grating ruler,when the grating ruler is in effect,according to the feedback of the grating signal,the servo motor constantly rotates forward and backward to correct the position of the drag plate,and the speed is fast and slow,and the vibration is generated by the uneven speed.
●Grating reading head(ruler)bracket installation factors
The installation of the grating reading head bracket is very important in the installation process of the machine tool with the grating ruler,if the grating bracket is not installed,the data read by the grating ruler reading head is not correct,causing the feedback signal to be unstable,causing the motor to work abnormally and produce vibration,and will make the positioning accuracy of the machine tool unstable.
●Bearing quality factors
In the process of machine tool movement,sometimes due to bearing quality problems;lead screw vibration caused by bearing raceway failure or retainer breakage.In this case,it can be judged according to the vibration sound source of the lead screw,when the bearing has a problem,the lead screw will emit a vibration sound during the movement of the drag plate,such as the closer the drag plate is to the support seat at one end of the lead screw,the higher the vibration audio of the lead screw, the bearing at this end may have a problem.
●Other factors
During the use of the machine tool,the lead screw vibration will be caused by insufficient lubrication,the wear failure of the sliding guide rail and the failure of the motor encoder.In this case,it is necessary to check item by item to eliminate the vibration failure.