| 摘要 |
PURPOSE:To permit a simpler circuit constitution to readily, speedily and accurately detect the oil leakage position by encoding an optical fiber cable by marking. CONSTITUTION:An optical fiber cable 50 is formed by bundling oil-detecting elements 51-54 made of four optical fibers which have oil-detecting parts 51a-54a, shown by white, and masked parts 51b-54b not detecting oil within a given length L, the lengths of the oil-detecting parts and the masked parts being doubled successively in order to encode. One end 50c of the optical fiber cable 50 is connected to a projector 60, and the other end 50d to a light-receiving means 70. Amplifying the output signals of light-receiving elements 71-74 before adding them to a logical circuit 90 permits the detection of the conditions of the penetrating light quantity decreased by the attachment of oil to the oil-detecting elements 51-54, with each oil leakage position specified. |
