Intrinsically safe proximity switch for winning machines (coal-getting machines, degraders) in underground mining (deep mining)

摘要

The invention relates to an intrinsically safe proximity switch (7) for winning machines (2) in underground mining. This proximity switch (7) is mounted on the machine body of the winning machine (2). It has a switch (16) which is influenced during machine motion by the magnetic field of a permanent magnet (4), which magnetic field limits the travel of the winning machine (2). In order to increase the extent and hence the effectiveness of this magnetic field, an amplifier magnet (reinforcer magnet) (23) is located in the switch housing (12) of the proximity switch (7), to be precise on the side of the switch (16) facing away from the permanent magnet (4). It focuses the magnetic field emerging from the permanent magnet (4) and extends it considerably in the direction of the proximity switch (7). In consequence, the proximity switch (7) responds even when it is moved past at a greater or different distance from the permanent magnet (4). <IMAGE>