US Patent 11535369 Self-folding propeller

A propeller assembly includes propeller blades that self-fold when not in use, which reduces the overall footprint of the propeller assembly and enables efficient storage. During flying conditions, the propeller blades unfold and extend to a flight configuration that enables the generation of lift on the propeller blades and consequently to an attached aerial vehicle. In various embodiments, the transitioning of the propeller blades between a flight and folded configuration may be enabled by torsion springs coupled to each propeller blade. For example, the torsion springs cause each propeller blade to rotate and self-fold when no external forces are applied. Alternatively, during flying conditions, centrifugal forces that arise as the propeller assembly rotates counteract the torsion springs, enabling each propeller blade to achieve an extended flight configuration. Therefore, the propeller blades of the propeller assembly are optimally oriented without the need for human intervention.