Water cooling mechanism for lower transmission of single crystal furnace

The utility model relates to a water cooling mechanism for lower transmission of a single crystal furnace, which comprises a water outlet pipe joint, a water inlet pipe joint, a water cooling shaft, a built-in water pipe and a rotary joint, the upper end of the built-in water pipe is communicated with a water inlet of the water cooling shaft, the lower end is communicated with a water pipe of the rotary joint, and the water outlet pipe joint and the water inlet pipe joint are in threaded connection with the rotary joint. And the upper end of the rotary joint is connected with the lower end of the water-cooling shaft, so that the water-cooling shaft can rotate freely under the condition that the positions of the two water pipe joints are fixed. The water-cooling shaft comprises a main shaft body, an annular water channel body and a shaft end cone, the annular water channel body is located in the main shaft body, the shaft end cone is located on the upper portion of the main shaft body, and the built-in water p