Research on sensor used to detect chain-broken on armoured face conveyor

Abstract：To the detection of chain-broken in armoured face conveyor,a scraper detecting sensor was proposed in which special magnetic field is constructed in side section of conveyor chute and hall element is used as sensitive element to the magnetic field.The fault of single chain-broken can be detected based on the sensor.It is presented that the magnetic intensity difference between scraper going through the sensor and no scraper going through it（MID） is one of the most important performance parameter.After modeling magnetic field,the relationships between MID and length of permanent magnet,location of permanent magnet and location of hall element were researched based on ANSYS.The results indicate that MID reaches peak 308 Gs when the length of permanent magnet is 100 mm and the permanent magnet is at such a position where the distance from the edge of side section of conveyor chute is 30 mm and the hall element from the edge of pan of chute is 80 mm.Measurement on the prototype designed on the rule is carried out.MID of the prototype is 265 Gs.It is enough to scraper detection.