Machine tool maintenance bearing fault detection circuit

During the production and maintenance process, bearings often wear out, machinery gets stuck, and cannot operate normally. In severe cases, parts may be damaged. This article introduces a bearing fault detector
that can be used by mechanics . Based on the changes in sound and light on the detector, maintenance personnel can quickly determine faults in the operation of the motor bearings and repair or replace them in time.     (1) Circuit composition The bearing fault detector circuit is mainly composed of bearing detection sensor, signal processing circuit IC1, light-emitting diode LED, transistor VT, audio amplifier integrated circuit IC2, speaker Y and related resistance and capacitance components , as shown in Figure 6-41 Show.     (2) Circuit principle After turning on the power supply, IC1 is powered on and works, and its ④ pin and @ pin both output high level, causing VT to conduct. The LED lights up. At this time, there is no input signal to the ③ pin of IC2 , and the speaker Y is not d, = it, Yu, day.     When the probe of the detection sensor is in contact with the metal end cover of the running motor bearing, the detection sensor will output an alternating signal that changes with the vibration frequency of the bearing. This signal is input from the ① pin of the ∞ port and passes through After IC1 internal circuit amplification, frequency selection delay, shaping and trigger driving, it is output from the ④ pin and @ pin of IC1. The alternating signal output by pin ④ of IC1 makes VT work in the switching state of alternate on and off , and the LED flashes and lights up. The alternating signal output by the @ pin of IC1 is amplified by 1C2 and then sounds through the speaker Y.     When the bearing is operating normally. The LED is always on or flashes, and speaker Y emits a continuous and steady sound; if the sound of speaker Y is high and low with interruptions. If the LED lights up intermittently, it means the bearing is short of oil or damaged.     RP1 is used to adjust the sensitivity of the signal processing circuit. RP2 is used to adjust the speaker output volume.