Canister and evaporative fuel-processing system employing same

An evaporative fuel-processing system for an internal combustion engine for a vehicle, said engine having a fuel tank, and an intake system, comprising:

• a canister including;
• a casing including a top wall having an inner surface, a vertical wall having an inner surface, first and second chambers formed in said casing and each accommodating an adsorbent, a partition member partitioning said first and second chambers from each other, a plurality of first protuberances formed on said inner surface of said top wall at a portion thereof facing toward said first chamber, and a plurality of second protuberances formed on said inner surface of said vertical wall at a portion thereof facing toward said first chamber;
• a first filter mounted in said first chamber in a fashion abutting on said plurality of said first protuberances;
• a first space defined in said top wall between said first filter and said portion of said inner surface of said top wall,
• a second filter mounted in said first chamber in a fashion abutting on said plurality of said second protuberances;
• a second space defined in said vertical wall between said second filter and said portion of said inner surface of said vertical surface, said second space communicating with said first space;
• a charging port formed in said top wall at a location corresponding to said first chamber and opening into said first space, said charging port connecting said first space to said fuel tank;
• a purging port formed in said top wall at a location corresponding to said first chamber and opening into said first space, said purging port connecting said first space to said intake system;
• and
• an atmospheric air port formed in said top wall at a location corresponding to said second chamber.