Locking device capable of realizing power-off self-locking of set position of rotary steering engine

The invention discloses a locking device capable of realizing the power-off self-locking of a set position of a rotary steering engine. The device comprises a steering engine rocker arm, a self-locking skeleton, a self-locking middle rotating shaft, a self-locking rocker arm, a self-locking sliding block, a self-locking pawl, a spring, a pin shaft and a pawl rocker, wherein the steering engine rocker arm is connected to four uniformly distributed threaded holes in the large-radius end of the self-locking middle rotating shaft through four bolts; the self-locking pawl is arranged on the upper part of the self-locking rocker arm, and is connected to a round lug boss on the middle upper part of the self-locking rocker arm through the pin shaft; the pin shaft is in clearance fit with a round hole of the self-locking pawl and the round lug boss on the middle upper part of the self-locking rocker arm; a dowel is arranged in a dowel hole of the pin shaft after the pin shaft is connected with the self-locking pawl and the self-locking rocker arm; the threaded end of the pawl rocker is connected to a threaded hole in the small-radius end of the steering engine rocker arm; the other end of the pawl rocker penetrates through an open groove of the self-locking pawl and a hollowed circular ring of the self-locking rocker arm; the self-locking sliding block is fixed in an upper sliding way of the self-locking skeleton through two screws; the two ends of the spring are connected to mounting holes of the self-locking pawl and the self-locking rocker arm respectively.