The motorized spindle of engraving and milling machine is a high-speed and high-rigidity precision motor. It is supported by precision rolling bearings, lubricated by grease and cooled by external circulating water. The engraving (milling) spindle is generally used vertically. The accuracy of the method used will directly affect the engraving and milling quality and the working life of the spindle. 1. Avoid impact. Strong impact,especially at the end of the main shaft and the front end cover, is not allowed. Otherwise, precision bearings and precision of the main shaft will be damaged, resulting in loss of rotation precision of the main shaft.
2. correct installation and clamping. Before installation, it should be confirmed that the state of the spindle motor is normal, mainly indicating that the appearance is not damaged and the spindle rotates smoothly. Check that the insulation resistance of the stator to the ground is above 200М Ω with a shaking table. The fit tolerance between the outer diameter of the spindle motor sleeve and the clamping seat hole must ensure that the sleeve of the spindle motor can slide smoothly into the seat hole. Under no circumstances can a hammer or other tools be used to position the spindle. The clamping force should not be too large, otherwise the steel ball raceway of the precision bearing will be deformed and the precision and service life of the spindle will be affected. After clamping, check that the runout of the centering surface of the taper hole at the front end of the spindle should be no more than 0.003MM, and the spindle should rotate smoothly.
3. Installation of collet (ER type) gland and cutter. The installation of the cutting tool must ensure the rotary precision, otherwise it will produce severe vibration, affecting the quality and efficiency of engraving (milling) and bearing life. The collet, pressing cap and cutting tool as well as the taper hole at the front end of the spindle must be wiped very carefully. Excessive force should be avoided when assembling and disassembling the cutting tool. After assembly, check that the runout of the tool root is less than 0.01 mm. If the runout exceeds the tolerance, it shall be corrected by repeatedly loosening and tightening and adjusting the contact surface of the tool shank. If there is no improvement, check whether the contact surface is in a normal state and avoid disorderly beating.