| 摘要 |
PROBLEM TO BE SOLVED: To provide a drain dustproof device which is easily applied to a bus duct with a simple structure and achieves predetermined drainage performance and dustproof performance.SOLUTION: A drain dustproof device includes: a plate-like base part 13 which is closely attached to a bottom plate part 12 of a housing 6 and has a second water flow hole 19 communicating with a first water flow hole 18 formed at the bottom plate part 12 of the housing 6; a cylindrical upper case part 14 fastened to the base part 13; a cylindrical lower case part 15 which has a closed bottom, is detachably attached to the upper case part 14, and has a third water flow hole 22 at a bottom part; and a number of balls 17 which are disposed in an internal space 16 enclosed by the base part 13, the upper case part 14, and the lower case part 15 and make a water flow passage in the internal space 16 into a stray flow structure. |
