| 摘要 |
PURPOSE:To make it possible to discriminate the generation of liquid leakage, etc. and its generated position by means of a receiving signal of the optical signal, by utilizing very small reflection in the connecting part of the optical fiber. CONSTITUTION:The optical fiber 16 is so constituted that there is no connecting part between the distributor 13 and the object to be detected, for instance, to the adjacent part of the pipe, and a connecting part is provided on the object to be detected, for instance, the part laid along the pipe. When an optical pulse is sent out to the optical fiber 16 through the transmission optical fiber 14a and the optical distributor 13 from the optical pulse transmission part 11 by a signal from the pulse signal generation detecting part 10, in case of a normal state, the optical pulse is propagated in the optical fiber and it is detected by the receiving part 12. Now, for instance, in cace liquid leakage, etc. have occurred in the pipe, the optical pulse of time tn is detected by the receiving part 12, but the optical pulse of time tn+1 is not detected. When the connecting part as to each time is confirmed in advance, the position at which an accident has occurred can be detected by the time of the optical pulse which has not received the light. |
