Passive follow-up hydraulic robot rotary joint capable of continuously rotating

The invention discloses a passive follow-up hydraulic robot rotary joint capable of continuously rotating. The passive follow-up hydraulic robot rotary joint comprises a valve element, a valve sleeve, a valve body, a hydraulic cylinder, a hydraulic motor and a variable stiffness mechanism. The valve element, the valve sleeve and the valve body are sequentially and coaxially mounted in the hydraulic cylinder, and output shafts of the valve element and the valve body extend out of the right end of the hydraulic cylinder, penetrate through the hydraulic motor and then are connected with a flexible output mechanism; the valve element, the valve sleeve, the valve body, the hydraulic cylinder, the hydraulic motor, a high-pressure oil path and a low-pressure oil path form a hydraulic corner self-servo mechanism; the variable stiffness mechanism comprises a separation disc, a sweeping arm disc and a load disc, the sweeping arm disc is mounted on the valve element, the separation disc is mounted ...