Automatic protection device for 3D printer nozzle

The utility model discloses an automatic protection device for a 3D printer nozzle. The automatic protection device comprises a protective cover, a plurality of detection pieces, a printer nozzle and a driving mechanism, the protective cover is provided with a protective cavity, and a nozzle outlet communicated with the protective cavity is formed in the protective cover; the detection piece is arranged on the protective cover and comprises a first polar plate and a second polar plate; the driving mechanism is connected with the printer nozzle; and when the detection piece is touched, the first polar plate is electrically connected with the second polar plate, so that the printer nozzle is driven by the driving mechanism to retract into the protection cavity through the nozzle outlet. The technical scheme provided by the utility model has the beneficial effects that when an object collides with the printer nozzle, the object firstly contacts with the detection piece, so that the first polar plate is electrica