Patents by Inventor Joseph F. R. Eijsermans

Joseph F. R. Eijsermans 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).

  • High pressure discharge lamp with tungsten electrode rods having first and second parts
    Patent number: 6590340
    Abstract: The high-pressure discharge lamp comprises a sealed lamp vessel (1) having a quartz glass wall (2) enclosing a discharge space (3). Metal foils (4) are embedded in the wall, connected to electrode rods (6a) projecting from the wall into the discharge space. The electrode rods (6a) have a first part (7a) and a second part (7b). The second part is made of tungsten with a diameter of 120 to 180 &mgr;m or molybdenum with a diameter of 120 to 350 &mgr;m, or tungsten-molybdenum mixtures with a diameter of 120 to 350 &mgr;m. The second part, which is positioned within the wall (2), prevents premature failure of the lamp caused by leakage.
    Type: Grant
    Filed: June 22, 1999
    Date of Patent: July 8, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Joseph F. R. Eijsermans, Dorothea Seebode, Angela Jörres
  • High pressure discharge lamp with tungsten electrode rods having second parts with envelope of rhenium
    Patent number: 6534918
    Abstract: The high-pressure discharge lamp comprises a sealed lamp vessel (1) having a quartz glass wall (2) enclosing a discharge space (3). Metal foils (4) are embedded in the wall, connected to electrode rods (6) projecting from the wall into the discharge space. The electrode rods (6) have a first part (7a) and a second part (7b) with a diameter of between 250 and 350 &mgr;m and at least an envelope (7c) made of rhenium. The second part, which is positioned within the wall (2), prevents premature failure of the lamp caused by leakage.
    Type: Grant
    Filed: June 22, 1999
    Date of Patent: March 18, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Manfred Peterek, Joseph F. R. Eijsermans, Dorothea Seebode, Marcus Kubon, Angela Jörres
  • Rhenium-containing electrode for a high-pressure sodium discharge lamp
    Patent number: 4864191
    Abstract: A high-pressure sodium discharge lamp provided with a solid electrode consisting mainly of tungsten plus a small quantity of rhenium, and free of alkaline earth metals. The addition of rhenium suppresses sodium attack which caused the tip end of the electrode to break off before the desired lamp life was reached.
    Type: Grant
    Filed: May 4, 1988
    Date of Patent: September 5, 1989
    Assignee: U.S. Philips Corporation
    Inventors: Martinus H. A. Van De Weijer, Joseph F. R. Eijsermans