Dirt detection method for cleaning device and dirt collecting device

A dirt collection device comprising:

• a chassis, said chassis having a chamber formed therein for dust collection;
• a feed pipe provided in said chamber, said feed pipe connecting said chamber with the external;
• a support member set in said chamber;
• a trigger (300) slidably set in said chamber, said trigger having a lower end thereof suspended and facing said chamber and an opposing upper end thereof slidably connected to said support member;
• and
• a cavity formed on said chassis, said cavity being set opposite to said upper end of said trigger, so that said upper end of said trigger closes said cavity after sliding,
• wherein said feed pipe extends upward from a lower end of said chamber into said chamber;
• said feed pipe and said chassis are integrally formed, and
• wherein the dirt collection device further comprises a partition, which together with said chassis forms a closed cabin inside said chamber, wherein said feed pipe has an upper end thereof extended into the closed cabin;
• said partition has a through hole formed thereon to connect the interior of said closed cabin and the interior of said chamber.