Automatic door opening and closing device

The utility model relates to an automatic door opening and closing device which comprises a gear, a rack, a support, a driving air cylinder, a door and a supporting rod, the support is composed of a gear installation frame, a driving air cylinder installation frame and a sliding block track, a round through hole is formed in the center of the gear installation frame, and the driving air cylinder is composed of a connecting handle, a cylinder body, a piston rod, a connector, a sliding block and a door connecting block. When the piston rod of the driving cylinder retracts, the rack on the door is driven to rotate along the gear to open the door, and when the piston rod of the driving cylinder extends out, the door can be closed, the heavy door can be automatically opened and closed, the labor intensity can be effectively relieved, and the convenience of opening and closing the door is improved. 本实用新型涉及一种自动开关门装置，包括齿轮，齿条，支架，驱动气缸，门，支撑杆，所述的支架由齿轮安装架，驱动气缸安装架，滑块轨道组成，所述的齿轮安装架中心开有圆形通孔，所述的驱动气缸由连接柄，缸体，活塞杆，连接头，滑块，门连接块组成，当驱