| 摘要 |
PROBLEM TO BE SOLVED: To prevent leak of a transmitted beam due to diameter expansion deformation by improving pressure-resistant performance of a tubular body.SOLUTION: A tubular body 1 is installed so that a light such as sunlight and light of illumination are vertically transferred through an inclusion body 2 such as a fluid to be a core. Even when pressure of the inclusion body 2 increases due to difference of elevation of the tubular body 1, the tubular body 1 is subjected to no diameter expansion deformation by reinforcement wire 3 by providing the reinforcement wire 3 along the thick wall part 1b or the outer peripheral surface 1c of the tubular body 1. As a result, the coated surface 11 of a low curvature rate member to be the inner peripheral surface 1a of the tubular body 1 is kept flat and no irregularities are generated.SELECTED DRAWING: Figure 1 |
