Patents by Inventor David R. Schlaefer

David R. Schlaefer 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).

  • Green helmet respiratory protection device
    Patent number: D436234
    Type: Grant
    Filed: March 10, 1998
    Date of Patent: January 9, 2001
    Assignee: 3M Innovative Properties Company
    Inventors: M. Antonia S{acute over (a)}ez, David R. Schlaefer
  • Red helmet respiratory protection device
    Patent number: D469580
    Type: Grant
    Filed: March 10, 1998
    Date of Patent: January 28, 2003
    Assignee: 3M Innovative Properties Company
    Inventors: David R. Schlaefer, M. Antonia Sáez