US Patent 8715382 Ventilation member

A ventilation member (100) of the invention includes a tubular part (11), a gas permeable filter (19), and a cover part (31). In an attached state where the tubular part (11) is fit into the cover part (31), gaps functioning as gas passages (AR2 and AR3) are formed between a bottom portion (35) of the cover part (31) and the gas permeable filter (19) and between a side wall portion (39) of the cover part (31) and a body portion (17) of the tubular part (11). The opening area (S2) of a filter-end opening (15) with respect to an in-plane direction (WL) perpendicular to the thickness direction of the gas permeable filter (19) is larger than the opening area (S1) of a connection-end opening (13) with respect to the in-plane direction (WL).