| 摘要 |
PROBLEM TO BE SOLVED: To obtain a ventilation non-percolation unit that retains a ventilation non- percolation sheet on a unit different from a housing and is constituted of two rubber parts and a ventilation non-percolation sheet with a simple constitution and excellence in moldability of the rubber parts, assemblability, and retention of a ventilation non-percolation sheet.SOLUTION: A ventilation non- percolation sheet is clamped and retained between a rubber outer case and a rubber inner case. The ventilation non-percolation sheet is clamped between the inner case side face of the perforated top plate part of the outer case in rotational symmetry centering on an axial line and the outer case side end face of the inner case in rotational symmetry centering on an axial line. The cylindrical part inner peripheral surface of the outer case has a tapered inner cylindrical surface that keeps a diameter reduced toward the end face on the opposite side of the perforated top plate part of the cylindrical part. The outer peripheral surface of the inner case has a tapered outer cylindrical surface that keeps a diameter larger than the tapered inner peripheral surface of the outer case in a free state and reduced by fitting with the tapered inner peripheral surface. |
