Speed transmission apparatus

Speed transmission apparatus, arranged between a drive engine and a drivable receiving device,

• comprising
• a first rotary casing (3, 27) arranged so as to be able to turn about a first axis of rotation (6),
• a double epicyclic gear train which comprises a first train and a second train and which is arranged at least partially in the said first rotary casing (3, 27), between a driving input connected to the drive engine and an output shaft (2, 32), arranged so as to be able to rotate about a second axis of rotation and connected to the drivable receiving device, the above-mentioned double train establishing between the driving input and the output shaft (2, 32) a transmission ratio between an input rotation speed and an output rotation speed,
• a first rotation transmission (12, 20, 21;
• 30) arranged at an intermediate output of the first epicyclic gear train,
• a second rotation transmission (14;
• 36) arranged at an intermediate input of the second epicyclic gear train,
• a first intermediate shaft (20;
• 30) arranged in one of the said first and second rotation transmissions, so as to be able to rotate about a third axis of rotation,
• a first electric motor brake (24;
• 38) acting on the first intermediate shaft (20;
• 30) and capable of modifying a speed of rotation thereof, and
• control means (25;
• 40) electrically connected to the first motor brake (24;
• 38) and controlling this so as to be able to continuously modify the speed of rotation of the first intermediate shaft (20;
• 30) and therefore the transmission ratio between the said input rotation speed and the said output rotation speed.