Patent ID: 8504871

Claim:
A safety output device of a control apparatus, the safety output device configured to send normal output data sent from an arithmetic device of the control apparatus to an operation terminal portion and also to execute a self-diagnosis, the safety output device comprising: an output controller configured to make an instruction to output normal output data calculated or designated by the arithmetic device and preset first self-diagnosis pattern data synchronously with a control cycle set by the arithmetic device; a normal output unit configured to convert the normal output data sent from the output controller into a digital signal and to output the digital signal as a normal output signal synchronously with the control cycle; a test pattern generating unit configured to encode the first self-diagnosis pattern data sent from the output controller into a pulse train signal having a pulse width equal to or smaller than a preset pulse width and to output the pulse train signal in accordance with a baseband transmission system; a combination output unit including a combining unit configured to combine the pulse train signal with the normal output signal to generate a combined output signal and an output interface unit configured to transform the combined output signal from the combining unit into an operation-terminal-portion output signal for the operation terminal portion through conversion into an operating signal level of the operation terminal portion, and to send the operation-terminal-portion output signal; a reconfiguration unit including an input interface unit configured to take in the operation-terminal-portion output signal and a pattern reconfiguration unit configured to decode the inputted operation-terminal-portion output signal and to thereby reconfigure the operation-terminal-portion output signal as second self-diagnosis pattern data; and a comparator configured to compare the first self-diagnosis pattern data with the second self-diagnosis pattern data to judge the presence or absence of a difference between the first self-diagnosis pattern data and the second self-diagnosis pattern data, wherein the presence or absence of an anomaly is judged based on the difference between the first self-diagnosis pattern data and the second self-diagnosis pattern data compared to each other, whereby the output of the normal output data from the arithmetic device and the self-diagnosis are performed in parallel.