Alexander Miles of Duluth, Minnesota patented an electric elevator (U.S. pat# 371,207) on October 11, 1887. His innovation in the mechanism to open and close elevator doors greatly improved elevator safety. Miles is notable for being a black inventor and successful business person in 19th Century America.
Elevator Patent – Automatic Closing Doors
The problem with elevators at that time was that the doors of the elevator and the shaft had to be opened and closed manually. This could be done either by those riding in the elevator, or a dedicated elevator operator. People would forget to close the shaft door. As a result, there were accidents with people falling down the elevator shaft. Miles was concerned when he saw a shaft door left open when he was riding an elevator with his daughter.
Miles improved the method of the opening and closing of elevator doors and the shaft door when an elevator was not on that floor. He created an automatic mechanism that closed access to the shaft by the action of the cage moving.
His design attached a flexible belt to the elevator cage. When it went over drums positioned at the appropriate spots above and below a floor, it automated opening and closing the doors with levers and rollers.
Miles was granted a patent on this mechanism and it is still influential in elevator design today. He was not the only person to get a patent on automated elevator door systems, as John W. Meaker was granted a patent 13 years earlier.
He died in 1918 and was inducted into the National Inventors Hall of Fame in 2007.