Constant-temperature fermentation device

The utility model discloses a constant-temperature fermentation device which comprises a heat preservation cylinder with an opening in the upper end, a plurality of supporting legs arranged at the bottom of the outer wall of the heat preservation cylinder, a heat conduction cylinder arranged in the heat preservation cylinder, a plurality of electric heating rods arranged on the inner wall of the heat preservation cylinder, and a water inlet valve communicated with the lower part of one side of the outer wall of the heat preservation cylinder, a driving motor is installed at the upper end of the heat conduction barrel, a feeding port is downwards formed in one side of the upper end of the heat conduction barrel, a sealing cover is rotationally connected to one side of the inner wall of the feeding port, one side of the upper end of the heat conduction barrel communicates with a one-way valve, a collecting barrel is arranged on one side of the outer wall of the heat preservation barrel, and an air guide pipe is