||The operation of mechanical equipment requires the use of a lubrication system. The detection of the quality and contamination of lubricants remains an important part of today's industry. Our laboratory has previously developed an online automatic detection device for the concentration of iron particles in the oil, so that it can instantly know the operation status of the mechanical equipment and prevent the damage of mechanical equipment at an early stage. The detection principle of the device was the magnetic flux detection method, but the Hall sensor and the detection accuracy of the device were still insufficient and need to be improved. Therefore, this study explored the effect of different Hall sensors on the accuracy of detection. The sensor W135 was selected. Results showed that when the iron particle concentration was 800ppm, the Hall voltage difference could achieve 88mV. Compared with the previous results used the sensor AH49E where the Hall voltage difference was 8mV, its sensitivity was increases by about 11 times.|
Prior to the detection of the EDM fluid, the calibration was performed using eight different iron particle concentrations. Results showed that the measurement errors were less than 5 ppm. For the non-line detection, when the removal amount was 2000 mg, the Hall voltage value of W135 was 83 mV, which was about 5.18 times higher than that of AH49E (16 mV). For on-line detection, the Hall voltage difference of W135 was 80mV, which is 19 times higher than the 4.2mV of AH49E. Results showed that the W135 Hall sensor was much more sensitive than the AH49E. Finally, the ferrous debris in the EDM fluid was analyzed to improve the accuracy and stability of the device.
This study also improved the display unit of the detection device to make it more suitable for intelligent manufacturing engineering. After compiled the microcontroller “Ardunio”, it matched with the LCD panel, so that the iron particle concentration value of the oil could be instantly displayed in the smart phone using the Bluetooth device to instantly monitor the quality of the oil. The operator could simply observe the wear condition of the mechanical equipment.