Patents by Inventor John Prewer

John Prewer 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: 5012621
    Abstract: A lift shaft which includes a plurality of self-supporting, prefabricated shaft modules which can be stacked. The lift shaft is constructed from one or more generally "plain" modules; a module containing a fully assembled lift car, optionally containing a counterweight which is temporarily supported for transit to the erection on-site; a fully assembled upper lift motor room module, including winding apparatus and electronic equipment for the lift; and a pit module which is to be suspended from a module above. The lift shaft and modules are designed so that they can be used as containers for fully assembled lift cars and/or counterweights between the factory and the building site so that a lift shaft module can be craned into position with a complete car and/or counterweight.
    Type: Grant
    Filed: October 2, 1989
    Date of Patent: May 7, 1991
    Assignee: Inventio AG
    Inventors: Leslie Power, John Prewer