Inner gearing type gear rack power transmission mechanism

The invention relates to an inner gearing type gear rack power transmission mechanism, and radically solves such defects as short service life and weak stability in traditional half-gear shaft transmission mechanisms. The inner gearing type gear rack power transmission mechanism comprises a half-gear frame, a top piston arranged on the half-gear frame, a half-gear shaft, and a half gear arranged on the half-gear shaft, wherein racks are respectively arranged on the inner walls of the left and right sides of the half-gear frame; the half-gear shaft is positioned in the half-gear frame; and the half gear is engaged to the rack at the left side or the right side in the half-gear frame. The inner gearing type gear rack power transmission mechanism is characterized in that the half-gear frame is limited in a guide groove of a guide rail through the outer walls of the left and right sides; the top piston is mounted on the half-gear frame through a piston pin; a bottom piston is coaxially arranged at the bottom of the half-gear frame and the top piston, is limited in a damper cylinder rightly below the half-gear frame, and fits the inner wall of the damper cylinder; a damping spring immersed in lubricating oil is limited in the damper cylinder; and multiple oil leading holes are formed in the damper cylinder, and are respectively communicated with the guide groove and an inner frame of the half-gear frame.