The servo drive system of the CNC horizontal milling and boring machine serves as the core link connecting the CNC system and the actuator, responsible for accurately transmitting motion instructions. Its operational stability directly determines the positioning accuracy and machining efficiency of the machine tool. Servo drive system faults often manifest in the form of coordinate axis jamming, abnormal speed, alarm shutdown, etc. If not handled properly, it can easily expand the scope of the fault. The scientific disposal plan should follow the principle of "diagnosis and positioning first, classification and disposal later, verification and consolidation later", and accurately implement policies based on the electrical system and mechanical characteristics.
The key to fault diagnosis is "layered investigation and precise positioning". Firstly, check the appearance and alarm information: check the alarm codes on the driver panel to preliminarily determine the type of fault (such as overcurrent, overvoltage, overload, etc.); Check whether the power and signal lines are loose, whether the plugs are oxidized, whether the cables are damaged, and eliminate the basic connection fault. Subsequently, perform a power-off test: use a multimeter to measure whether the output voltage of the power module is stable, check the insulation resistance of the servo motor, and determine whether the motor winding is short circuited or grounded; Disassemble and inspect the mechanical transmission components, check if the lead screw and guide rail are stuck, and avoid servo overload caused by mechanical jamming.
Common faults need to be classified and targeted for disposal. Overcurrent faults are often caused by motor or driver abnormalities: if the motor makes abnormal noises and heats up, it is necessary to disassemble and inspect the bearing wear, replace damaged bearings, and perform dynamic balancing again; If the internal module of the drive burns out, it is necessary to replace it with a module of the same model and calibrate the parameters. Overvoltage faults are often related to power fluctuations or braking units: check the stability of the power grid voltage and add a voltage regulator; If the braking unit fails, it is necessary to replace the braking resistor or adjust the braking timing parameters.
The positioning accuracy deviation fault needs to take into account both electrical and mechanical calibration: check the servo gain parameters through the numerical control system, and if the parameters drift, reload the factory set values and fine tune them; Using laser interferometer to detect coordinate axis positioning errors and correcting them through system compensation function; If the mechanical backlash is too large, it is necessary to adjust the pre tightening force of the screw or replace the worn ball screw.
After troubleshooting, it is necessary to verify through no-load and load testing: run each coordinate axis without load, observe the smoothness of movement and alarm situation; Load standard specimens for processing, test dimensional accuracy and motion stability. Daily prevention requires establishing a regular maintenance mechanism: regularly cleaning the drive cooling fan to avoid overheating; Check the aging condition of the cable and replace it in a timely manner; Regularly calibrate servo parameters and mechanical accuracy to reduce the risk of failure from the source. This disposal plan can efficiently solve common faults in servo drive systems and ensure stable operation of machine tools.