CNC Router Representative
In many CNC milling machines, vibration and noise and frictional noise are inevitably generated at work due to the fact that a number of drive shafts, gears and bearings are used in the variable speed system of the spindle. The CNC milling machine main drive system speed is in the machine does not stop working in the state, CNC Router controlled by the computer to complete, so it is more than ordinary machine noise generated more continuous, more representative.
A digital milling machine, the noise in the initial use of a larger noise and noise from the main drive system, with the use of time to extend the noise is growing, CNC Router with sound level meter in the spindle 2000r / min speed, measured The noise is 85.2 dB.
Mechanical system by any outside of the exciting force, CNC Router the system will be due to the excitation force in response to vibration. This vibrational energy propagates throughout the system, and when it propagates to the surface of the radiation, the energy is converted into a pressure wave,CNC Router which is then passed through the air, that is, acoustic radiation. Therefore, the three steps of excitation response, internal transmission and acoustic radiation are vibration noise, frictional noise and impulse noise formation process.
CNC milling machine of the main drive system soil is precisely because the gears, bearings and other parts through the excitation response, and transmission and radiation within the system and the emergence of noise, and these parts and because of the abnormal situation, CNC Router so that the exciting force plus So that the noise increases.
Machine main drive system gear in the operation of the noise are:
① gear in the engagement, CNC Router the teeth and teeth between the continuous impact of the gear at the meshing frequency under the forced vibration and bring the impact of noise.
② due to the external excitation of the role of the gear generated by the inherent frequency of the fan free vibration and bring noise.
③ due to gear and drive shaft and bearing assembly eccentricity caused by the rotation of unbalanced inertia force, which produced a consistent with the speed of low-frequency vibration. CNC Router With the rotation of the axis, each time a signal is emitted once.
④ due to the friction between the teeth and teeth caused by the self-excited vibration generated by the gear and bring friction noise. If the tooth surface uneven, CNC Router will cause rapid periodic impact noise.
The CNC milling machine spindle speed system has a total of 38 rolling bearings. Bearing and journal and support hole assembly, preload, concentricity, lubrication conditions and the role of the load on the bearing size, radial clearance and so have a great impact on the noise. CNC Router And the bearing itself manufacturing bias, to a large extent determine the bearing noise. Rolling bearings most prone to deformation of the site is its inner and outer ring. Inside and outside the ring under the influence of external factors and their own accuracy, it is possible to produce rocking vibration, axial vibration, radial vibration, bearing ring itself,CNC Router radial vibration and axial bending vibration.
And gear the same token, the higher the speed of the bearing, CNC Router the greater the frequency of rotation, the noise will increase the bearing rolling inner and outer ring of the respective accuracy If not high, will become the main factors affecting the bearing noise Roller or bearing Inside and outside the ring on a lot of depression, in the spectrum to show the frequency of the higher harmonics, the higher the noise caused.