Patent ID: 7913848

Claim:
An air filling bag with an outer film strengthening structure, comprising: two outer films, adhered to each other to form an air chamber by means of hot sealing, each outer film including: a first film sheet, a second film sheet, stacked with the first film sheet, a plurality of first hot sealing lines, formed by adhering the first film sheet to the second film sheet by means of hot sealing in a first direction, and a plurality of second hot sealing lines, formed by adhering the first film sheet to the second film sheet by means of hot sealing in a second direction approximately perpendicular to the first direction, wherein the first hot sealing lines and the second hot sealing lines are arranged in a grid with respect to each other; and a main check valve positioned between the outer films and having one end projecting from the two outer films, the main check valve including: two first inner films, stacked together and projecting from the air chamber, two second inner films, positioned between the first inner films and projecting from the air chamber, wherein the length of one end of the second inner films is shorter than the length of one end of the first inner films, and a first air passageway formed by adhering the first inner films to the second inner films by means of hot sealing and connecting the air chamber with an outside region, the main check valve being compressed by air in the air chamber to shield the first air passageway after outside air flows in the air chamber via the first air passageway.