Patents by Inventor Stuart B. Spence

Stuart B. Spence has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4793441
    Abstract: The elevator car is guided in its movement through the hoistway by the two conventional guide rails positioned one on each side of the car, and also by a third guide rail positioned on one side of the car adjacent one of the car doors. The blade of the third guide rail is parallel to the sides of the car, and is engaged by a pair of guide rolls which are mounted on a beam extending out from under the car floor. The third guide rail is mounted in the hoistway on the bracket beams which secure the counterweight guide rails in place. The purpose of the third guide rail is to prevent lateral oscillation of the car as it moves through the hoistway.
    Type: Grant
    Filed: October 20, 1987
    Date of Patent: December 27, 1988
    Assignee: Otis Elevator Company
    Inventors: Janis Cilderman, Stuart B. Spence