Patent ID: 7017216

Claim:
A method of manufacturing a bladder assembly comprising the steps of: (i) forming a watertight bladder having a valve device thereon; (ii) forming an inflatable air cushion inside the watertight bladder, the air cushion having an outer surface area substantially the same as an inner surface area of the watertight bladder; (iii) forming at least one air valve extended from the air cushion through the watertight bladder and secured thereto; (iv) inflating the air cushion with air through at least one air valve; (v) filling water into the watertight bladder through the valve device; and (vi) drawing an amount of air out of the watertight bladder through the valve device until the amount of air in a predetermined space of the watertight bladder is substantially reduced to no larger than 20% by volume and a water screen is thus formed around the air cushion due to siphonage.