Patent ID: 9616634
Date: 2017-04-11
CPC Classifications: B31D,B65D,Y10T

Claim:
1. A method for making a cushioning air bag with a predetermined opening in an air cylinder turning zone, comprising: providing an air cylinder sheet, constituted by a plurality of air cylinders formed by adhering two sheets of outer film along a plurality of longitudinal heat sealing lines and a plurality of transversal heat sealing lines; forming a plurality of turning points on the plurality of air cylinders or the plurality of longitudinal heat sealing lines, wherein the turning points form at least two turning lines parallel to at least one axis of the plurality of transversal heat sealing lines, wherein a virtual turning middle line is defined at the middle between the at least two turning lines, the virtual turning middle line is parallel to at least one axis of the plurality of the transversal heat sealing lines; forming a portion of the two sheets of outer film at a non-heat sealing section in the turning zone to be stuck to each other to form at least one heat sealing block by heat sealing, the heat sealing block being narrower than one of the air cylinders that the heat sealing block is attached to, and being shorter than or a same length as the non-heat sealing section so as to contract an area of the air cylinders at the non-heat sealing section in the turning zone forming a plurality of nodes positioned on two outermost ones of the longitudinal heat sealing lines of the air cylinder sheet by marking or heat-sealing, the nodes being positioned on two opposite respective sides of the virtual turning middle line from each other and at a predetermined distance from the virtual turning middle line, wherein the nodes are not positioned at the turning lines, and the markings or heat seals which form the nodes are distinct from the longitudinal heat sealing lines; turning the air cylinder sheet along the turning lines; and adhering two respective sides of the turned air cylinder sheet, which are on the opposite respective sides of the virtual turning middle line from each other, with a plurality of lateral heat sealing lines respectively positioned on the two outermost ones of the longitudinal heat sealing lines of the air cylinder sheet; wherein, the plurality of lateral heat sealing lines are extended from the nodes and along the two outermost ones of the longitudinal heat sealing lines of the turned air cylinder sheet, two lateral sides of the air cylinder sheet between the plurality of nodes and the virtual turning middle line form the non-heat sealing section;