""H. Bockhacker of Berlin was granted German patent DE18349 on December 22, 1881 for "Tür ohne Luftzug" or "Door without draft of air".

Theophilus Van Kannel, of Philadelphia, was granted US patent 387,571 on August 7, 1888 for a "Storm-Door Structure". The patent drawings filed show a three-partition revolving door."

The main purpose was to cut down on drafts, exclude street noise and let people into a building and keep out the snow, dust rain etc..
Source(s):
http://en.wikipedia.org/wiki/Revolving_door

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H. Bockhacker of Berlin was granted German patent DE18349 on December 22, 1881 for "Tür ohne Luftzug" or "Door without draft of air".

"Theophilus Van Kannel, of Philadelphia, was granted US patent 387,571 on August 7, 1888 for a "Storm-Door Structure". The patent drawings filed show a three-partition revolving door. The patent describes it as having "three radiating and equidistant wings . . . provided with weather-strips or equivalent means to insure a snug fit". The door "possesses numerous advantages over a hinged-door structure . . .it is perfectly noiseless . . . effectually prevents the entrance of wind, snow, rain or dust . . ." "Moreover, the door cannot be blown open by the wind . . . there is no possibility of collision, and yet persons can pass both in and out at the same time." The patent further lists, "the excluding of noises of the street" as another advantage of the revolving door. It goes on to describe how a partition can be hinged so as to open to allow the passage of long objects through the revolving door. The patent itself does not use the term "revolving door"."
Source(s):
http://en.wikipedia.org/wiki/Revolving_door#History

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