Opening adjusting structure of spray head in special flame-retardant device for sponge

The invention provides an opening adjusting structure of a spray head in a special flame-retardant device for sponge, and belongs to the technical field of sponge production equipment. A rectangular air outlet hole is formed in the spray head, a metal sheet I and a metal sheet II are arranged near the tail end of the air outlet hole, the metal sheet I and the metal sheet II intercept the whole cross section of the air outlet hole, an avoiding opening is formed in the wall, close to the middle of the metal sheet I, of the air outlet hole, and a plurality of air guide grooves are formed in one side faces which the two end portions of the metal sheet I and the metal sheet II are mutually abutted, the apertures of the air guide grooves are gradually reduced to disappear from the end part to the middle part, so that the middle parts of the metal sheet I and the metal sheet II are tightly attached to each other to intercept the air outlet hole, and the thermal expansion coefficient of the metal sheet I is larger th