Ultrasonic negative pressure circulating extraction device

The invention discloses an ultrasonic negative pressure circulating extraction device used for extracting active components of natural products, mainly comprising a reflux evaporator, an ultrasonic generator, a vacuum pump, a low temperature cooling agent circulating pump, an infusion pump, an extraction flask and a collection flask, wherein, the vacuum pump can create a negative pressure state in the reflux evaporator to allow the collection flask which is connected with the reflux evaporator keep the negative pressure state, so as to allow the solvents to be benefit for the evaporation and condensation of the collected extract in the evaporator; the low temperature cooling agent circulating pump can allow the evaporator to keep low temperature inside, so as to allow the solvents vaporized to the evaporator to be subject to high efficient condensation and return to the extraction flask which is connected with the evaporator; and the infusion pump can continuously convey the feed liquid in the extraction flas