Large-torque continuous rotating type SMA motor

The invention provides a large-torque continuous rotating type SMA motor. At least two drive units are installed on a main shaft in a series connection way, and the main shaft is driven to continuously rotate by sequentially actuating each drive unit. Each drive unit mainly comprises an SMA wire, a spring, a rotating disk, a ratchet wheel and a ratchet pawl, wherein one end of the SMA wire is installed on a ceramic support seat by a flattened stainless steel pipe, and the ceramic support seat is installed on an upper plate of the motor; the other end of the SMA wire is installed on the rotating disk by a ceramic pulley; one end of the spring is hung on the rotating disk, and the other end is installed on a bottom plate by an adjusting bolt; the ratchet pawl is installed on the rotating disk, simultaneously pressed by a spring sheet installed on the rotating disk and meshed with the ratchet wheel; and the ratchet wheel is installed on the main shaft by a key groove. The drive units areformed by the joint actua