Patents by Inventor Ralf Holzhauer

Ralf Holzhauer 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).

  • Escalator handrail drive
    Patent number: 4875568
    Abstract: An escalator handrail is driven by a pair of angularly offset rollers. The angular offset of the rollers causes a wedging effect at the roller nip whereby the driving force imparted by the rollers to the handrail is increased.
    Type: Grant
    Filed: January 5, 1989
    Date of Patent: October 24, 1989
    Assignee: Otis Elevator Company
    Inventors: Dietrich E. Hermann, Ralf Holzhauer
  • Escalator handrail entry safety switch actuator
    Patent number: 4619355
    Abstract: Two generally U-shaped pieces are adapted to fit together end-to-end so that when they are nested in an appropriately-sized passage in an escalator entry box, they cooperate to form a generally cylindrical actuator that at one end has brushes protruding through the opening of the entry box and that is slideable in the entry box over the handrail to actuate a safety shutoff switch located therein in the unlikely event of a foreign object being pulled by the handrail into the entry box.
    Type: Grant
    Filed: August 6, 1985
    Date of Patent: October 28, 1986
    Assignee: Otis Elevator Company
    Inventors: Willy Adrian, Ralf Holzhauer