| 摘要 |
<p>Light guides which cannot be transversed disruptively by flames are necessary for optic and/or optoelectric surveillance, for example of magnitudes of physical and chemical nature with processes in regions where there is a risk of explosion. For this purpose, each light guide in the risk region is made of a single fiber within its proper longitudinal opening, sufficiently small, and is then vented, without support, in a region with no risk or with lesser risks. As an alternative, an economic technical form of execution, small tubes (11a, 11b) are used longer than 25 mm and preferably with a 6 mm bore. In another alternative, the light guides are casted in the openings (12a, 12b). </p> |
