Propeller propulsion unit comprising a heat engine and an electric motor and aircraft comprising such a propeller propulsion unit

A propeller propulsion unit, comprising at least one kinematic system comprising:

• a heat engine consuming fuel;
• a main shaft rotated at an output of the heat engine;
• an electrical energy generator configured to generate electrical energy from the rotation of the main shaft;
• an electric motor configured to generate a rotary movement as output from the electrical energy generated by the electrical energy generator;
• a coupling element comprising a toothed gear and a shaft;
• and
• a propeller rotated by the coupling element,
• wherein the at least one kinematic system selectively assumes one of a first configuration or a second configuration at a given time,
• wherein the toothed gear of the coupling element is movable through translational movement between a position in which the toothed gear is coupled to a toothed gear attached to the main shaft of the heat engine and a position in which the toothed gear of the coupling element is coupled to a toothed gear of the electric motor,
• wherein, in the first configuration, the coupling element is coupled to and driven by a rotational output of the electric motor,
• wherein, in the second configuration, the coupling element is coupled to and driven by a rotation of the main shaft.