Numerical control system including internal register self-reset function with serial communication signal monitoring

Patent metadata

Field	Value
Publication number	US-2016209827-A1
Application number	US-201614992288-A
Country	US
Kind code	A1
Filing date	Jan 11, 2016
Priority date	Jan 16, 2015
Publication date	Jul 21, 2016
Grant date	—

Abstract

In a numerical control system including a numerical controller and a plurality of I/O units, a serial communication signal monitoring circuit is included inside the I/O unit to monitor a serial communication signal (data and an idle signal). When a state is detected in which a serial communication signal is high or low for a predetermined time or longer, the numerical control system acknowledges the state as disconnection of the serial communication signal, and generates a reset pulse signal to reset an internal register of the I/O unit. With this configuration, when the power supply of the numerical controller is turned off/on, it is unnecessary to turn off/on the power supply of the I/O unit.

First claim

1 . A numerical control system comprising:
a numerical controller; and one or more I/O units connected to the numerical controller, the numerical control system performing transmission and reception of input and output signals using serial communication between the numerical controller and the I/O unit, wherein the I/O unit includes a monitoring part that monitors a serial communication signal transmitted from the numerical controller, the monitoring part includes
a determining part that determines that the power supply of the numerical controller is stopped when the serial signal is stopped for a predetermined time or longer, and
a reset signal output part that outputs a reset signal to a register inside the I/O unit when the determining part determines that the power supply of the numerical controller is stopped.

2 . The numerical control system according to claim 1 , wherein the determining part is configured to set the predetermined time.

3 . The numerical control system according to claim 1 , wherein the reset signal output part is configured to set the length of the output time of the reset signal.

4 . The numerical control system according to claim 1 , wherein
the I/O unit includes
a transmission and reception part that receives the serial signal from the numerical controller or an I/O unit at a front stage and transmits the serial signal to an I/O unit at a subsequent stage, and
a stop part that stops the serial signal to be transmitted to the I/O unit at a subsequent stage when the determining part determines that the power supply of the numerical controller is stopped.

5 . An I/O unit connected to a numerical controller using serial communication, comprising:
a monitoring part that monitors a serial communication signal transmitted from the numerical controller, wherein the monitoring part includes
a determining part that determines that the power supply of the numerical controller is stopped when the serial signal is stopped for a predetermined time or longer, and
a reset signal output part that outputs a reset signal to a register inside the I/O unit when the determining part determines that the power supply of the numerical controller is stopped.

Assignees

• Fanuc Corp

Inventors

• Baba Takahiro
• Hada Kouji
• Miyazaki Yoshito

Classifications

• G05B2219/33093

  Real time clock interface between serial I-O and processor · CPC title

• G05B19/402 Primary

  characterised by control arrangements for positioning, e.g. centring a tool relative to a hole in the workpiece, additional detection means to correct position (G05B19/19 takes precedence) · CPC title

• G05B2219/34286

  Intelligent positioning I-O · CPC title

• G05B19/4148 Primary

  characterised by using several processors for different functions, distributed (real-time) systems (G05B19/4141 takes precedence) · CPC title