A changeover valve, comprising:
- a valve body (1) and an internal-communication air duct (11) and a driving device arranged in the valve body (1);
- wherein the valve body (1) is connected with a housing (2) of a vacuum cleaner, the housing (2) is provided with a ventilation opening (21), an air inlet duct (31) for driven inlet air and an air outlet duct (32) for driven outlet air, the ventilation opening (21) is provided with a filter element (4), a first end of the internal-communication air duct (11) is connected with the ventilation opening (21), an outer side of the internal-communication air duct (11) is connected with the driving device, so that the driving device drives a second end of the internal-communication air duct (11) to rotate by a preset angle, the second end of the internal-communication air duct (11) is connected at the air inlet duct (31) and the air outlet duct (32) communicates with an external space, or the second end of the internal-communication air duct (11) is connected at the air outlet duct (32) and the air inlet duct (31) communicates with the external space,
- wherein the valve body (1) is driven by the driving device, so that the second end of the internal-communication air duct (11) is connected with the air outlet duct (32) or the air inlet duct (31), and the air flow direction in the internal-communication air duct (11) is changed, such that the air flow flows to the internal-communication air duct (11) through the filter element (4) arranged at the ventilation opening (21) to ensure that the air flow flowing into the air inlet duct (31) is filtered, or the air flow flows to the filter element (4) through the internal-communication air duct (11), and dust on the filter element (4) is blown away,
- wherein when the second end of the internal-communication air duct (11) is connected at the air inlet duct (31) and the air outlet duct (32) communicates with the external space, the air flow enters the air inlet duct (31) for the driven inlet air by the driving device after entering the internal-communication air duct (11) via the filter element (4) and the ventilation opening (21), and then is driven to enter the air outlet duct (32) for the driven outlet air so as to flow to the external space via the air outlet duct (32);
- and
- wherein when the second end of the internal-communication air duct (11) is connected to the air outlet duct (32) and the air inlet duct (31) communicates with the external space, the air flow enters the air outlet duct (32) through the air inlet duct (31) communicating with the external space, and then enters the internal-communication air duct (11), and then flows to the ventilation opening (21) and the filter element (4) through the internal-communication air duct (11).