Yarn spraying device and spinning device for preparing nanofiber

The invention discloses a yarn spraying device and a spinning device for preparing nanofiber. The yarn spraying device comprises a spray pipe, a La Farr pipe-shaped inner hole is formed in the spray pipe, the throat portion of the La Farr pipe-shaped inner hole is communicated with a liquid inlet, one end of the La Farr pipe-shaped inner hole is provided with a yarn spraying opening, and the other end of the La Farr pipe-shaped inner hole is provided with an air inlet; a yarn spraying mesh is arranged at the yarn spraying opening; the mesh number of the yarn spraying mesh is about 300-500. Compared with the prior art, the spinning device has no requirements for the conductivity of a solution, and the range of the spinning solution is expanded. When the nanofiber is prepared, high voltage is not needed, and the instrument safety problems are solved; the yarn spraying device is arranged to be capable of being handheld, and therefore the operation is convenient and easy when spinning is performed.