Harmonic-distortion-free low-frequency line spectrum generator

The invention belongs to the field of underwater acoustic transducers, and relates to a harmonic-distortion-free low-frequency line spectrum generator which comprises a base shell, a cylinder body is arranged in the base shell, a piston is arranged at an opening in the upper end of the cylinder body, a diaphragm is arranged at the upper end of the piston, the edge of the diaphragm is fixed to the outer wall of the upper end of the base shell, and a cavity is formed by the diaphragm and the cylinder body. A piston rod is arranged in the base shell, a piston is fixed to the upper end of the piston rod, the piston rod is still connected with a sliding bearing arranged in a center hole of the cylinder body, a servo motor is arranged in the base shell, the output end of the servo motor is connected with the input end of a speed reducer, and the output end of the speed reducer is connected with a transmission mechanism. The transmission mechanism is connected with the piston rod. According to the invention, low-fre