Patents by Inventor Roger C. Drew

Roger C. Drew 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).

  • Security-transfer systems
    Patent number: 5469657
    Abstract: A security system controls two sliding (or other) doors 6 and 7 to allow only one door to be opened at a time. A pivoted bolt 13 is pushed by a mechanical link 16 into the opening-path of the door 6 when a lever 15 that abuts the leading-edge of the other door 7 pivots back upon opening movement of that door. A corresponding mechanism includes a link 26 which couples a pivoted bolt 23 to a lever 25 that abuts the door 6, such that the bolt 23 blocks opening of the door 7 when the door 6 begins to open. The mechanical links 16 and 26 may be replaced by hydraulic links.
    Type: Grant
    Filed: February 22, 1994
    Date of Patent: November 28, 1995
    Inventor: Roger C. Drew