Fault Diagnosis of CNC Machine Tools

With the development of electronic information technology, the world machine tool industry has entered the era of mechatronics with digital manufacturing technology as its core, among which CNC machine tools are one of the representative products. The faults and elimination methods of CNC machine tools also need to be understood. This article describes common troubleshooting methods and exclusion of CNC machine tools.

After analyzing the fault information, among the many reasons, determine the main reasons for the possible faults, and then analyze these main reasons.

More than 80% of CNC machine tools fail from external causes, and less than 20% are caused by internal causes. Therefore, diagnosis and repair must also follow the law of failure, from outside to inside, from shallow to deep. If it is a functional fault, check the performance of cylinders, solenoid valves, motors, contactors, etc., and then input signal components such as sensors and limit switches. Once again, electrical connections, arrests, active wire and cable, etc. . Botou Giant Heavy Machinery Co., Ltd. is a professional production, vertical lathe, CNC vertical lathe, CNC gantry milling machine, gantry machining center, CNC floor boring and milling machine manufacturers, troubleshooting of CNC machine tools is a great experience.

These external components are greatly affected by environmental factors, such as collision, corrosion, dust, etc., and poor lubrication and mechanical wear of the components are often the source of the fault. With the exclusion of external causes, it is possible to dig deeper into the CNC to find faults internally. Electrical schematic diagrams and logic ladder diagrams are two powerful tools, but foreign-imported numerical control equipment often does not provide information and data about the internal system. It can only be judged using simple boxes and previous empirical analysis. The order of internal fault diagnosis is from the power supply part to the public circuit part to the dedicated circuit part.

The power supply part generally judges the faulty component due to the large power of the component and the common test whether there is abnormal heating or not. The public circuit is often the input and output circuit board of the system. They collect the input signals from various places and convert them into identifiable signals for the system. They also transmit the commands sent by the system. Often by the A / D, D / A converter, op amp, optocoupler, micro-relay and other components of the same or similar channels, through the static and dynamic comparison of these channel circuit measurements can determine whether a channel fault. The comparative measurement method is also commonly used in the inspection of special circuits. The voltage and waveform of the test terminal of the circuit board are tested, and compared with the original record in the normal state, the circuit board can be quickly determined whether it is in good condition. Circuit board spare parts are more convenient and effective.