Periodic light projecting sensor control device and sensor system ensuring mutual interference does not occur

#This application claims the priority benefits of Japan Patent Application No. 2017-021583, filed on Feb. 8, 2017. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.

#The disclosure relates to a sensor control device configured to control a plurality of sensor units and a sensor system including the sensor control device, and particularly, to a sensor control device configured to prevent mutual interference between a plurality of sensor units and a sensor system.

#A sensor system configured to determine whether a workpiece (object to be detected) is present based on detection values (amounts of light received) in photoelectric sensors using a plurality of photoelectric sensors is known as a conventional technique. Further, a sensor system configured to prevent mutual interference caused when light projected from a specific photoelectric sensor enters another photoelectric sensor is known as a conventional technique. For example, Japanese Unexamined Patent Application Publication No. 2014-096697 discloses a sensor system in which a plurality of sensor units storing respective pieces of identification information are operated after a delay time determined according to respective pieces of identification information has elapsed using a synchronization signal transmitted at predetermined periods as a starting point and thus mutual interference is prevented.

#FIG. 1 is a block diagram showing an example of a configuration of a main part of a sensor system according to Embodiment 1 of the disclosure.

#FIG. 2 is a schematic diagram of an overview of the sensor system according to Embodiment 1 of the disclosure.

#FIGS. 3(a) and 3(b) are schematic diagrams of a sensor unit according to Embodiment 1 of the disclosure, in which FIG. 3(a) is a perspective view of a sensor unit, and FIG. 3(b) is a schematic diagram showing a state in which sensor units are connected in series.

#The disclosure provides a sensor control device and a sensor system through which it is possible to automatically detect whether mutual interference occurs between a plurality of sensor units, and it is possible to automatically set periodic light projection timings for preventing mutual interference.

#In one embodiment, a sensor control device includes a light projection control part configured to instruct a light projection operation performed by a light projection part for each of a plurality of sensor units including the light projection part and a light reception part; and a light projection timing setting part configured to set periodic light projection timings when each of the sensor units is periodically operated based on results of light projection control performed by the light projection control parts with respect to each of the sensor units and detection results obtained by the light reception part of each of the sensor units.

#According to the above configuration, it is possible to set periodic light projection timings based on light projection control results and detection results for the plurality of sensor units. Therefore, for example, it is possible to set light projection timings for the plurality of sensor units by the way that light projection timings do not overlap. Thus, it is possible to provide a sensor control device that automatically sets appropriate light projection timings for the plurality of sensor units.