Patent ID: 7694701

Claim:
A structure of check valves for use in an air-packing device for packing a product, comprising: a plurality of air containers each being made of upper and lower packing films by applying separation seals where a check valve is provided to each air container; upper and lower check valve films for forming a plurality of check valves where peeling agents of predetermined pattern are applied between the upper and lower check valve films, the upper and lower check valve films being attached to one of the upper and lower packing films; an air input established by one of the peeling agents on the air-packing device for receiving air from an air source; an air passage formed in each check valve by heat-seals between the upper and lower check valve films by two or more air guide seals, the air passage including a narrow channel formed by the separation seal and the air guide seal between the upper and lower check valve films; and a common air duct formed between the upper and lower check valve films for providing the air from the air input commonly to the plurality of check valves; wherein heat-sealing between the upper and lower check valve films is prevented in a range where the peeling agent is applied, thereby creating the common air duct.