| 摘要 |
PROBLEM TO BE SOLVED: To provide an insulation bush for a thunderstorm trouble countermeasure capable of securing prescribed creepage distance and voltage resistance capable of withstanding a thunderstorm surge without using a special material which is not a general-purpose part causing the increase of cost and improving an insulation material.SOLUTION: In the insulation bush 1 made of an insulation material and comprising: a cylindrical barrel part 2 externally fitted around a binding member Bn of binding an apparatus enclosure X to a supporting body and fitted to the axial periphery of the binding member Bn; and a collar part 3 with a hole-opening disk shape connected to one edge of the barrel part 2 and abutted against a washer Z, a rising part 4 with a ring shape risen along the outer periphery of the collar part 3 toward the outside in the axial direction of the binding member Bn is provided, and further, a taper face 3b gradually diameter-reduced or diameter-expanded along the axial direction is formed at the outer circumferential face of the collar part 3, thus the creepage distance Y2 from the washer Z to the apparatus enclosure X is secured by prescribed distance or more, and an apparatus stored in the apparatus enclosure X is protected from a thunderstorm surge. |
