Impeller, drainage pump and indoor unit of air conditioner

A drainage pump comprising:

• a pump housing;
• a motor;
• and
• an impeller comprising:
• an impeller shaft;
• a plurality of blades comprising long blades and short blades, the long blades being fixedly connected to the impeller shaft and extending outward along a radial direction of the impeller shaft;
• and
• a circular disc comprising a plate-shaped structure sleeved on an outer circumference of the impeller shaft and an annular structure fixedly connected with the outer edge of the plate-shaped structure,
• wherein the short blades are fixedly connected to the plate-shaped structure and spaced apart from the impeller shaft and the annular structure,
• wherein the long blades are spaced apart from the annular structure,
• wherein the plate-shaped structure is provided with a plurality of balance through holes between two adjacent long blades and communicating front and rear sides of the plate-shaped structure,
• wherein the plurality of balance through holes at least including a balance through hole circumferentially disposed between two adjacent short blades, and two balance through holes each circumferentially disposed between a different adjacent set of a long blade and a short blade,
• wherein each balance through hole being circumferentially disposed between two adjacent blades of the plurality of blades is spaced apart from the two adjacent blades and the annular structure,
• wherein at least a portion of each balance through hole is disposed radially outward of the two adjacent blades, and
• wherein the impeller is movably accommodated in the pump housing, and an output shaft of the motor is fixedly connected with the impeller shaft.

An indoor unit of an air conditioner, comprising a condensate tray and a drainage pump, the drainage pump comprising:

• a pump housing;
• a motor;
• and
• an impeller comprising:
• an impeller shaft;
• a plurality of blades comprising long blades and short blades, the long blades being fixedly connected to the impeller shaft and extending outward along a radial direction of the impeller shaft;
• and
• a circular disc, comprising a plate-shaped structure sleeved on an outer circumference of the impeller shaft and an annular structure fixedly connected with the outer edge of the plate-shaped structure,
• wherein the short blades are fixedly connected to the plate-shaped structure and spaced apart from the impeller shaft and the annular structure,
• wherein the long blades are spaced apart from the annular structure,
• wherein the plate-shaped structure is provided with a plurality of balance through holes between two adjacent long blades and communicating front and rear sides of the plate-shaped structure,
• wherein the plurality of balance through holes at least including a balance through hole circumferentially disposed between two adjacent short blades, and two balance through holes each circumferentially disposed between a different adjacent set of a long blade and a short blade,
• wherein each balance through hole being circumferentially disposed between two adjacent blades of the plurality of blades is spaced apart from the two adjacent blades and the annular structure, and
• wherein at least a portion of each balance through hole is disposed radially outward of the two adjacent blades,
• wherein the impeller is movably accommodated in the pump housing, and an output shaft of the motor is fixedly connected with the impeller shaft, and
• wherein a suction port of the drainage pump is in communication with the condensate tray.