Low-noise electric lawnmowers with curved cutting blades

An electric lawnmower comprising:

• a drive unit;
• and
• a mowing unit coupled to the drive unit and comprising a set of cutting blade units and a discharge conduit, mechanically attached to the set of cutting blade units, wherein:
• each of the set of cutting blade units comprises a blade enclosure and a cutting blade defining a blade center axis,
• the cutting blade comprises a hub and a set of cutting extensions, each connected to the hub,
• the set of cutting extensions comprises at least five cutting extensions evenly spaced about the blade center axis,
• each cutting extension in the set of cutting extensions comprises a cutting edge having a curved shape,
• the cutting blade is associated with a circular boundary, having a perimeter,
• each of the set of cutting extensions comprises a circumferential edge, having a length and extending along the perimeter of the circular boundary from the cutting edge,
• a sum of the length of the circumferential edge of all cutting extensions in the set of cutting extensions is at least 50% of the perimeter of the circular boundary,
• the cutting blade comprises a cutting portion and a lifting portion such that the cutting edge is a part of the cutting portion,
• the lifting portion is directly connected to the cutting portion,
• both the cutting portion and the lifting portion protrude away from a plane defined by the cutting edge of the cutting blade of all cutting blade units in the set of cutting blade units, and
• the cutting portion and the lifting portion form a continuous curve having a variable curvature radius.