US 12,386,331 B2
Control device for performing test of safety signal circuit, and control method for performing test of safety signal circuit
Noboru Hirose, Yamanashi (JP)
Assigned to FANUC CORPORATION, Yamanashi (JP)
Appl. No. 17/801,578
Filed by FANUC CORPORATION, Yamanashi (JP)
PCT Filed Mar. 8, 2021, PCT No. PCT/JP2021/008960
§ 371(c)(1), (2) Date Aug. 23, 2022,
PCT Pub. No. WO2021/182386, PCT Pub. Date Sep. 16, 2021.
Claims priority of application No. 2020-044157 (JP), filed on Mar. 13, 2020.
Prior Publication US 2023/0101050 A1, Mar. 30, 2023
Int. Cl. G05B 19/05 (2006.01)
CPC G05B 19/058 (2013.01) [G05B 2219/14006 (2013.01)] 4 Claims
OG exemplary drawing
 
1. A control device for performing a test of a safety signal circuit that cuts off, based on an input signal from an emergency stop switch, a motor drive signal for driving a motor included in a machine tool, the control device comprising:
the safety signal circuit;
a first controller having a first output terminal and a first input terminal; and
a second controller having a second output terminal and a second input terminal,
the first controller including:
a timing unit configured to measure an elapsed time and direct a start of a first safety signal circuit test based on the elapsed time; and
a first circuit test control unit configured to perform a first detection of whether or not a safety signal circuit input signal is inputted from the first input terminal when a safety signal circuit output signal is outputted from the first output terminal to a first circuit installed between the first output terminal and the first input terminal or the safety signal circuit output signal being outputted from the first output terminal to the first circuit is stopped, and perform the first safety signal circuit test using a result of the first detection,
the second controller including:
an execution confirmation unit configured to confirm whether or not the first safety signal circuit test by the first test control unit is complete; and
a second circuit test control unit configured to perform a second detection of, after the execution confirmation unit has confirmed that the first safety signal circuit test is complete, whether or not a safety signal circuit input signal is inputted from the second input terminal when a safety signal circuit output signal is outputted from the second output terminal to a second circuit installed between the second output terminal and the second input terminal or the safety signal circuit output signal being outputted from the second output terminal to the second circuit is stopped, and perform a second safety signal circuit test using a result of the second detection, wherein
both the first circuit and the second circuit have a path through the emergency stop switch.