US Patent 10494084 Propeller pitch control system

A control system for controlling the pitch of a propeller, the system including a propeller shaft, a blade swivel device having a rotary control element suitable for placing the blades in an angular position corresponding to a desired propeller pitch, and a transmission presenting an outlet member coupled in rotation with the rotary control element of the blade swivel device. The transmission includes a variable speed drive having drive, control, and outlet rotors that are coupled in rotation respectively with the propeller shaft, with a control member, and with the outlet member of the transmission. With the variable speed drive, the speed of rotation of the outlet member of the transmission is a predetermined function of the speeds of rotation not only of the propeller shaft, but also of the control member.