The high speed of linear servo feed system is a system engineering, and each link in the system must meet the requirements of high speed transmission.
Inversely proportional to the moment of inertia of the ball screw feed system and the system's maximum processing speed, in order to improve acceleration, the system should make finite element analysis and CAD optimized design, under the premise of meet the dynamic and static stiffness, reducing the number of parts, optimize parts parameters and make it high-strength, lightweight.
To choose the precision ball screw assembly matched high speed rolling linear guide at the same time. For example, Japanese THK's SHS Quartet and other load series, SNR, SNS high stiffness heavy duty series, SSR ultra high-speed series, the line speeds up to 200m/min or more. German INA's drum-shaped roller linear guide according to user requirements can also configured with "RUDS" damping sliding seat, the amplitude decreased to 1/30 of the original, noise decreased significantly to meet the high-speed, high-precision, heavy cutting requirements.
To attach great importance to the installation accuracy of precision high-speed ball screw assembly on the machine tool, it plays an important role in improve the critical speed Nc, positioning accuracy, improve stability at high speeds, reducing noise and so on. Screw both ends using pre-stretching high stiffness support structure, to ensure strictly screw both ends bearing and ball nut center "three coaxial". Should use ball screw special high rigidity thrust angular contact bearings.
Make full use of ball screw "synchronization" characteristic, high speed machining centers installed in pairs of high-speed precision ball screw assemblies, is the effective measure to improve the stability of the servo feed system at high speed, improved dynamic characteristics. For example, Japanese Makino Milling Machine production the A55E type of horizontal high-speed machining center and Niigata Iron Works of SPN50-H0 type horizontal high speed machining center and Toyoda Machine EV33 vertical high-speed machining center, have adopted the double motor double screw drive mode.
In the servo feed system, to configure the brake device, the flexible buffer, the self-locking in vertical transmission, and so on.
In the purchase and acceptance of precision high-speed ball screws, and to differentiate the general large lead ball screw, and require manufacturers to provide the ordered products operating speed, acceleration, precision, noise, temperature rise and other testing data. If you are using Si3N4 ceramic balls, you should check the Si3N4 ceramic balls accuracy, hardness, surface roughness, pressure-fed load test certificate. If the selection of strong cold hollow screw, should also check the straightness of the deep hole, the test results of the outer circle coaxiality. In order to ensure the reliability of the high-speed operation, and also view the screw shaft, nut, loop back device raw material and heat treatment inspection reports.
Source: http://www.machineballscrew.com Precision High Speed Ball Screw Assemblies.
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