Integrated small electric piston cylinder

The invention discloses an integrated small electric piston cylinder. The integrated small electric piston cylinder comprises a motor shell, a stator, a rotor, a motor main shaft, a nut, a piston rod,a lead screw and a supporting shell, the stator is fixed in the motor shell, the motor main shaft is of a hollow structure, the motor main shaft is fixedly connected with the rotor, the rotor is arranged in the stator, the supporting shell is arranged on the motor shell, the piston rod is vertically and slidably connected with the supporting shell, the lead screw is arranged in the piston rod andfixedly connected with the piston rod, and the nut is fixedly connected with the motor main shaft, and is in threaded fit with the lead screw. The integrated small electric piston cylinder is small in size and high in integration level; and the motor main shaft is of the hollow structure, the nut is installed at the lower end of the motor main shaft, and a containing cavity is formed between themotor main shaft and the nu