Air packing bag having film-type check valves
An air packing bag of plastic for shipping or storing goods is disclosed. The bag includes upper and lower sheets, a valve mechanism including upper and lower films and an intermediate heat-proof member, parallel bladders formed by the upper and the lower sheets, the bladders being perpendicular to the valve mechanism, seals each formed between two adjacent bladders, an air passage formed across the bladders for being in communication therewith, the air passage being adjacent the valve mechanism and having an air valve at one end, and coupling points formed on the upper sheet adjacent the air passage. Pressure inside the inflated bladders pushes both the upper and the lower films to urge against an inner surface of the upper sheet for blocking air from leaving the bladders.
1. An air packing bag comprising:
an upper sheet;
a lower sheet;
a plurality of seals formed on the upper and lower sheets defining a plurality of bladders;
an air passage formed across the plurality of bladders;
a film check valve disposed in each bladder, the film check valve in communication with the air passage, the film check valve comprising:
a lower film located between the upper sheet and the lower sheet;
an upper film located between the upper sheet and the lower film;
an intermediate heat-proof member separating the upper film and the lower film;
a plurality of spaced apart coupling points disposed within the bladder and further being spaced from the plurality of seals defining that bladder, the coupling points coupling the upper and lower films to each other at each coupling point location, the coupling points further coupling the upper and lower films to the upper sheet at each coupling point location such that when the bladder is under inflation the lower film and the upper film are urged against the upper sheet thus blocking air or other inert gas from leaving the bladder.
2. The air packing bag according to claim 1 wherein each of the plurality of bladders has an independent air inlet communicating with the air passage.
3. The air packing bag according to claim 1 wherein the plurality of seals are unevenly spaced.
4. The air packing bag according to claim 1 wherein the upper sheet, the lower sheet, the lower film and the upper film are made of plastic.