This Day in Patent History – The iconic “Imbertson inflatable gate” was patented on March 16, 1965

The “Imbertson inflatable gate” was an inflatable rubber dam patented by Norman Imbertson. Norman Imbertson worked at the Los Angeles Department of Water and Power in the US. In 1956, he thought of the idea of using a sealed rubber body attached to a foundation which could be raised or lowered by the addition or removal of water. The Imbertson inflatable gate evolved in to a flexible membrane filled with air or water which acted as a weir.
The Japanese company Bridgestone installed its first rubber dam in 1978. Since then it has supplied more than 800 inflatable rubber weirs for hydro power, irrigation, flood control and water supply projects throughout Europe, Asia and the Americas.

The standard construction of the rubber dam consists of an envelope of reinforced rubber securely clamped to a concrete foundation.

Installations of rubber dams are increasing throughout the world.

Here is an inflatable dam used for “decorative” purposes.

Here is an inflatable dam used in sewers. [Image credit – Getty Images]

Source: WaterPowerMagazine 

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