Coder transmission device of hollow billet revolving arm speed reducer

The utility model relates to a hollow billet revolving arm speed reducer and encoder transmission device, which comprises a rack, a speed reducer and an encoder which are arranged on the rack, and a bull gear which is arranged on an output shaft of the speed reducer, the transmission shaft is mounted on the rack through a mounting structure, and the encoder is mounted on the transmission shaft; the small gear is connected to the transmission shaft in a sleeved mode, the small gear is connected with the large gear in a meshed mode, and the encoder is driven to rotate through the large gear, the small gear and the transmission shaft. According to the transmission device, the hollow billet is screwed into the rotary arm encoder to be away from the influence of a high-temperature area on the encoder, and the service life of the hollow billet is prolonged. And the hollow billet is screwed into the rotary arm encoder without being influenced by the field working condition environment, so that the whole set of equip