Ultra-fine powder reducing and variable-pitch spiral feeding and micro-negative-pressure degassing device

The invention provides an ultra-fine powder reducing and variable-pitch spiral feeding and micro-negative-pressure degassing device. The ultra-fine powder reducing and variable-pitch spiral feeding and micro-negative-pressure degassing device comprises a motor bracket, a driving reduction motor, a conveying charging barrel, a silo, a spiral conveying shaft and reducing and variable-pitch spiral conveying blades, the spiral conveying shaft is arranged in the conveying charging barrel, an opening is formed in the top of the silo, the bottom of the silo is fixedly connected to the upper side of the left side part of the conveying charging barrel, a discharging outlet is formed in the lower side of the right side part of the conveying charging barrel, the reducing and variable-pitch spiral conveying blades are fixedly installed on the outer circumference of the spiral conveying shaft, an extraction shell between the silo and a right end cover is arranged on the upper side of the conveyingcharging barrel, a negati