Direct heating type constant-temperature dryer

The invention discloses a direct heating type constant-temperature dryer. The direct heating type constant-temperature dryer comprises an air inlet, an electric adjusting valve arranged at the tail end of the air inlet, condensers arranged below the right portion of the electric adjusting valve, a centrifugal fan arranged at the right side of the condensers, an air outlet arranged below the centrifugal fan, an evaporator arranged below the condensers, circulating conveying pipes connected with the two ends of the condensers and the two ends of the evaporator, a draught fan arranged at the left side of the condensers and a dehumidifying port arranged at the left side of the draught fan. According to the direct heating type constant-temperature dryer, since the two condensers are obliquely arranged, the heating area of fresh air is enlarged, the air supply volume of the fresh air is adjusted in combination with the electric adjusting valve, the heating speed of the condensers on the air is controlled, the heating speed is high, the heating effect is good, the energy ratio of the working effect of a main engine is increased, and the energy saving effect is achieved; compared with the traditional technology, cyclic heating of the air is not needed, and the air outlet can be externally connected with a heat conveying pipe to form a certain distance, so a fire can be prevented, and the safety of operation is enhanced.