System for taking nanofiber film through external magnetic field assisted microflow control and use method

The system comprises a micro-flow extrusion pump, a receiving roller, a plate capacitor and a control magnetic field, during application, a spinning solution is placed in an inner cavity of the micro-flow extrusion pump, a circuit where the plate capacitor and the control magnetic field are located is conducted, then the micro-flow extrusion pump is pushed, and the nano-fiber film is taken out through the receiving roller. The spinning liquid is injected from a liquid outlet of the extrusion nozzle, the injected spinning liquid passes through the control magnetic field, falls on the rotating receiving roller and is converted into spinning, then the spinning liquid is continuously injected, the rotating receiving roller continuously pulls and stretches the injected spinning liquid, and the spinning collected on the receiving roller is continuously increased to form a fiber film; and carrying out vacuum drying on the fiber film to obtain the nanofiber film. According to the design, not only can finer nanofibers