With the development of direct drive technology, the comparison between the linear screw stepper motor and the traditional "rotary servo motor ball screw" drive mode has attracted industry attention. Now some advanced machining center manufacturers are beginning to apply on their high speed machine tools.
The linear screw stepping motor reduces the problem of interpolation lag due to the simple mechanism of the transmission mechanism. The positioning accuracy, the reproduction accuracy, and the absolute accuracy are higher than the "rotary servo motor ball screw" by the position detection feedback control, and it is easy to implement. Linear screw stepper motor positioning accuracy can reach 0.1μm. "Rotary servo motor ball screw" up to 2~5μm, and requires CNC-servo motor - gapless coupling - thrust bearing - cooling system - high precision rolling Guide rail - nut seat - table closed loop The transmission part of the whole system should be lighter and the grating accuracy should be high. If you want to achieve high stability, "rotary servo motor ball screw" should adopt dual-axis drive, linear screw stepper motor is a high-heating component, need to take strong cold measures, to achieve the same purpose, linear screw stepper motor It will pay a higher price.
The linear screw stepper motor has considerable advantages. The linear screw stepper motor speed reaches 300m/min, the acceleration reaches 10g; the ball screw speed is 120m/min, and the acceleration is 1.5g. From the comparison of speed and acceleration The linear screw stepper motor has considerable advantages, and the speed of the linear screw stepper motor will be further improved after successfully solving the heat problem, and the "rotary servo motor ball screw" is limited in speed. Increase more.
The linear screw stepping motor has a mounting gap between the moving part and the fixed part, has no contact, and is not worn by the high-speed reciprocating motion of the mover. The long-term use has no change in the positioning accuracy of the movement, and is suitable for high-precision occasions. The ball screw can not guarantee the accuracy in high-speed reciprocating motion. Because of high-speed friction, the screw nut will wear and affect the accuracy of the motion. The demand for high precision cannot be met.