Stepper motor and the drive circuit of open-loop nc system, because of its simple structure, low price and reliable performance, has been widely applied in the economical nc machine tool, in the process of numerical control of machine tool industry in China occupies an important position. Stepping motors are often used for accurate positioning, and thus maintain out of step motor is very important. Out-of-step and its harm to the normal work of the stepper motor, each receiving a control pulse will move a step Angle, namely before further. If the continuous input control pulse, the motor is correspondingly continuous rotation. Stepper motor step steps including lost and more. Throw step, rotor steps forward is smaller than the pulse number; The step, the rotor steps forward more than the pulse number. Steps once lost and the interval number is equal to the number of integer times operation. Step throw serious when, will make the rotor to stay in one place or around a position on the vibration, step the more serious when, machine will be happened. Stepper motor open-loop feed system is an important part of, its performance directly affects the performance of the numerical control system. Step motor loss will affect the stability and control accuracy of the numerical control system, causing the deterioration of nc machine tools machining precision. Rotor acceleration is slow son force of a rotating magnetic field of stepper motor rotor n slow speed in rotating magnetic field of stepper motor, which is lower than in the phase velocity, step electric opportunity out of step. This is because the input motor power, the synchronous torque generated in step motor cannot make the rotor speed with the rotation speed of the stator magnetic field, causing loss of steps. Due to dynamic output torque of stepping motor with the continuous rise in frequency and reduce, therefore, any working frequency is higher than the frequency step will have lost. The step of stepper motor torque, drag the lack of ability. The solution: (1) make the stepping motor itself produces electromagnetic torque increased. Therefore can within the scope of rated current and appropriate increase the drive current. In the high-frequency range torque is insufficient, can be appropriately to improve the driving voltage of the drive circuit,To switch to large torque stepper motor, etc. (2) reduce torque stepper motor need to overcome. This can be appropriately reduce the frequency of motor operation, in order to improve the output torque of the motor; Set longer acceleration time, so that the rotor to get enough energy. The average speed of the rotor is higher than the average speed of the average rotational speed of rotor stator magnetic field is higher than the average rotational speed of the stator magnetic field, the stator current field for a long time, is greater than the rotor step further the time required, the rotor in the process of stepping won too much energy, caused the stepper motor output torque increase, making step motor more. When using stepper motor driver that make load, under the action of institutions, are more likely to produce the phenomenon, this is because the load downward movement, motor torque decreases as needed. The solution: reduce the stepper motor drive current, in order to reduce the output torque of stepping motor. Stepper motor and the load inertia to the stepper motor and load inertia, make the motor in the process of work don't start and stop immediately, but appears when the starting step, when to stop the step. Solution: through an acceleration and deceleration process, i. e. starting at low speed, and then gradually speed up to a certain speed, then gradually slow down until it stops. Reasonable, smooth deceleration control stepping driving system is reliable, efficient and accurate operation of the key. Step by step electric machine machine produce resonance resonance is also a cause of out of step. The continuous operation of the stepping motor, if the control pulse frequency is equal to the natural frequency of the stepper motor, will produce resonance. In a control pulse cycle, vibration is not sufficient attenuation, came to the next pulse, and near the resonance frequency dynamic error and leads to the largest stepper motor out of step. The solution: reduced stepper motor drive current; By adopting the method of subdivision driving; Damping methods, including mechanical damping method. The above method can effectively eliminate vibration of motor, avoid out-of-step phenomenon. the main products: stepper motor, brushless motor, servo motor, stepping motor drive, brake motor, linear motor and other kinds of models of the stepper motor, welcome to inquire. Telephone:
