COMMUNICATION UNIT AND SAFETY SYSTEM
FIG5 is a side view showing a configuration of a mounting hole of the unit main body in the communication unit according to the embodiment of the invention 
FIG5 is a side view showing a configuration of the mounting hole 9 of the unit main body 1. As shown in FIG5, the mounting hole 9 has an elongated hole 9b. The unit main body 1 is fixed to the aluminum frame 11 by inserting the fastening member 9a into the elongated hole 9b and fastening the fastening member 9a and the aluminum frame 11 to each other. The fastening member 9a may be a member capable of being fastened to the aluminum frame 11 and the like and is, for example, a cross slot screw, a hexagon head bolt, or the like. In addition, the mounting hole 9 may be configured such that the fastening member 9a is inserted thereinto, and may have a circular hole instead of the elongated hole 9b shown in FIG5.
side view
5
notched portion
10
communication units communication unit
['1. A communication unit (10),  characterized in that , the communication unit (10) comprises: a unit main body (1); a connection portion (2) which is provided in the unit main body (1) and connected to a safety input device (7) through a cable (8); a first input and output portion (3) which is provided at a first end (1a) on a connection portion side in the unit main body (1); and a second input and output portion (4) which is provided at a second end (1b) on a side opposite to the first end (1a) in the unit main body (1), wherein the first input and output portion (3) and the second input and output portion (4) are configured to be directly connected to each other when a plurality of the unit main bodies are connected to each other in series, and a notched portion (5, 51, 52) forming a disposition space for a terminal (8a) on the connection portion side of at least the cable is provided at the second end (1b) of the unit main body (1).']