Cyclonic separation device and application thereof

A vacuum cleaner, comprising:

• a cyclonic separator, comprising:
• a housing;
• and
• a cyclonic separation device provided in the housing to allow dirt in a dust-laden airflow to be separated, the cyclonic separation device comprising a first-stage cyclone separator and a plurality of second-stage cyclone separators located downstream of the first-stage cyclone separator in a flow direction of the airflow, the plurality of second-stage cyclone separators surrounding the first-stage cyclone separator;
• wherein
• the first-stage cyclone separator comprises an air guide channel and a first-stage cyclone channel surrounding a part of the air guide channel, and the dust-laden airflow enters, from the air guide channel, the first-stage cyclone channel for cyclonic separation and then enters the second-stage cyclone separators through the air guide channel;
• the air guide channel comprises a first air outlet channel and an air inlet channel spaced up and down and coaxially arranged, the first-stage cyclone channel surrounds the first air outlet channel, and in the flow direction of the airflow, the first-stage cyclone channel is located between the air inlet channel and the first air outlet channel;
• and
• after entering the first-stage cyclone channel through the air inlet channel and experiencing the cyclonic separation, the dust-laden airflow enters the second-stage cyclone separators through the first air outlet channel;
• wherein the first-stage cyclone separator comprises:
• a first cyclone with a tapered wall and having a cavity with an open top;
• and
• a separating member provided in the first cyclone and defining the first air outlet channel;
• wherein
• the first-stage cyclone channel is defined between the separating member and the first cyclone, and the separating member is provided with a plurality of through-holes arranged at intervals to make the first air outlet channel communicated with the first-stage cyclone channel;
• the at least part of the air guide channel extends linearly, and the first-stage cyclone channel extends spirally along a length direction of the at least part of the air guide channel;
• the cyclonic separation device further comprises an air flow-by opening located between the first-stage cyclone separator and the plurality of second-stage cyclone separators, and the plurality of second-stage cyclone separators surround the first-stage cyclone separator;
• and
• after entering the first-stage cyclone channel through the air guide channel and experiencing the cyclonic separation, part of the dust-laden airflow enters the second-stage cyclone separators through the air guide channel, and another part of the dust-laden airflow enters the second-stage cyclone separators through the air flow-by opening, wherein a filter screen is provided at the air flow-by opening.