MONITORING DEVICE FOR A TOOL IN AN AUTOMATIC TURNING MACHINE

摘要

A tool fracture in automatic turning machines has devastating consequences if this is not detected in good time. For this reason, a great number of monitoring devices have already been proposed in which the tool in use in each case is checked for damage during the operating cycle sequence. According to the invention, a sensing needle (15) is provided which is guided radially to the centre axis of the tool (drill 5) and with regard to its guide (swivel arm 12) is flexibly mounted in a housing (14). When a tool (drill 5) is present, the sensing needle (15) (sensing stroke h') coming down onto the tool actuates the contact bank (17) of a magnetic switch (reed switch 16/17). The scanning stroke (h) of the swivel arm (12) is mechanically coupled via a tie rod (20) to the return movement of the tool (drill 5) into the rest position. A signal pulse is produced in the scanning time by a second magnetic sensor (24/25), which signal pulse initiates testing of the potential prevailing at the switch line (18) by a monitoring circuit (27).