Patent ID: 8685193

Claim:
A method of manufacturing an expansion band, comprising the steps of: (a) bonding a first layer, a second layer and a third layer together to form a bond line, wherein said first layer and said second layer are sealed by said bond line on an outline to form an inner space between said first layer and said second layer, said inner space is being divided by said bond line into a plurality of air passages; (b) providing a plurality of elastic bands to extend between said second layer and said third layer, and fixing said elastic bands onto the outline of said first layer, said second layer and said third layer; wherein said step (a) further comprises the steps of: pressing said first layer, said second layer and said third layer to a die with a pre-determined pattern; and forming said bond line in accordance to said pre-determined pattern of said die to bond said first layer, said second layer and said third layer together; wherein said bond line seals the outline of said first layer and second layer to form said inner space and bonds regions of said first layer and second layer to divide said inner space into said plurality of air passages capable of communication with each other.