The present invention discloses a shooting device which includes a rotor which can make gyrus and forward and backward motions at an inner hole of a heating cylinder, and an embedded screw of the rotor is an axial extension, a speed reducer which is arranged at the axial extension of the rotor through the rotor, and a shooting device which is provided with a gyrus driving motor. The speed reduceris an epicyclic gear speed reducer, a sun gear of which is directly arranged at an output shaft of the motor, therefore the speed reducer can be greatly reduced and can be assembled in the manner of a small cubage.