DETECTING METHOD OF OPERATING POSITION OF LIMIT SWITCH DETECTING ORIGINAL POINT IN NUMERICALLY CONTROLLED MACHINE TOOL

摘要

PURPOSE:To confirm the operating position of a limit switch for detecting the original point, by calculating a position detecting pulse signal used from the first point, of time, when the limit switch for detecting the original point operates, to the second point of time, when one rotation signal of a motor is generated after said first point of time. CONSTITUTION:An original point aligning switch 6 and reset switch 10 are turned on to set the counting value of a counter 9 to zero. Then a function switch 11 is turned on to input a signal S1 of one rotation and pulse signal S2 for position detection to AND circuits 12, 13. Here a tool 1 is reset to the original point. At this time, a limit switch 4 for detecting the original point is tapped at a section E and turned on, then an FF circuit 14 is set, and an original point signal SB is generated at the first point of time T2 to count a pulse signal S2. After the point of time T2, the FF14 is reset at the second point of time T3 when the signal S1 of one rotation becomes a high level, and counting of the S2 is stopped. In this way, an operating position of the limit switch for detecting the original point can be clearly displayed.