| 摘要 |
PURPOSE:To decide a fault of a feedback loop when the contents of an error register are not set at zero after a dummy pulse is applied to the error register from a numerical controller to actuate a servo mechanism and then the contents of the error register are checked. CONSTITUTION:When a power supply is applied to a numerical controller, a prescribed number of dummy pulses are supplied to an error register 3 via an adder 2. The output of the register 3 undergoes a D/A conversion through a servo unit 4 and is amplified. Thus a motor 5 is revolved to set the contents of the register 3 at 0. The controller 1 reads the contents of the register 3 after a fixed time elapses. When the contents show 0, it is decided that a position feedback loop is nondefective. While a fault is decided with the feedback loop when the contents of the register 3 are not 0. Thus the power supply of the motor 5 is turned off, and an alarm is delivered. This check is possible at an optional time point with operation of a keyboard 8. Thus an assured diagnosis is possible to the position feedback loop, and the runaway is prevented with a servo system. |
