Patents by Inventor Wiggert Kroontje

Wiggert Kroontje 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: 4940923
    Abstract: Electrodeless low-pressure discharge lamp having a lamp vessel which is sealed in a gas-tight manner and which is filled with a metal vapor and a rare gas and which has a core of a magnetic material. During operation of the lamp an electric field is generated in the lamp vessel by means of a winding surrounding the core and a high-frequency supply unit connected thereto. A transparent electrically conducting layer is present on the inside of the lamp vessel, and is connected to an electric conductor located outside the lamp vessel by means of a lead-through member incorporated in the wall of the lamp vessel. The lead-through member is electrically connected to a contact strip of conducting material extending on at least the greater part of the circumference on the inside of the lamp vessel and is electrically connected substantially throughout its length to the transparent conducting layer.
    Type: Grant
    Filed: November 27, 1989
    Date of Patent: July 10, 1990
    Assignee: U.S. Philips Corporation
    Inventors: Wiggert Kroontje, Willem J. van den Bogert
  • Patent number: 4645967
    Abstract: An electrodeless low-pressure gas discharge lamp includes a glass lamp vessel (1) which is provided with a sealing member (6) connected to the wall of the lamp vessel by means of a suitable sealing material, and which has on its inner wall a conductive layer (7), at least part of which is transparent, that extends beyond the connection to the sealing member (6), the member being slightly recessed into the lamp vessel. The inner conductive layer can thus be connected in a simple manner to an electrical conductor, which during operation of the lamp is connected, for example, to one of the supply wires of the mains.
    Type: Grant
    Filed: February 5, 1985
    Date of Patent: February 24, 1987
    Assignee: U.S. Philips Corporation
    Inventors: Anton J. Bouman, Heiner Kostlin, Wiggert Kroontje
  • Patent number: 4645468
    Abstract: In devices provided with an evacuated bulb in which is present an activated metallic getter, hydrocarbons can be released or produced. As a result, the gas pressure and the heat conductivity increase. In devices according to the invention, for example, low-pressure sodium vapor discharge lamps, solar collectors, display tubes and image intensifiers, a getter auxiliary means is provided. The auxiliary means comprises an inorganic porous carrier charged with a transition metal having an atomic number from the series 23 to 29, 41 to 47 and 73 to 79, in elementary form or in oxide form, or with a combination of at least two of the said materials.
    Type: Grant
    Filed: October 2, 1985
    Date of Patent: February 24, 1987
    Assignee: U.S. Philips Corporation
    Inventor: Wiggert Kroontje
  • Patent number: 4588919
    Abstract: A low-pressure alkali metal vapor discharge lamp has a getter for bi- and triatomic gases and a getter holder in the arc tube near at least one electrode. The electrodes need be heated less strongly during evacuation of the prior to final dosing, as a result of which no emitter material of the electrodes is lost. The ignition voltage is considerably lower than that of conventional lamps without a getter.
    Type: Grant
    Filed: April 9, 1984
    Date of Patent: May 13, 1986
    Assignee: U.S. Philips Corporation
    Inventors: Wiggert Kroontje, Franciscus M. P. Oostvogels
  • Patent number: 4559471
    Abstract: In devices provided with an evacuated bulb in which is present an activated metallic getter, hydrocarbons can be released or produced. As a result, the gas pressure and the heat conductivity increase. In devices according to the invention, for example, low-pressure sodium vapour discharge lamps, solar collectors, display tubes and image intensifiers, a getter auxiliary means is provided. The auxiliary means comprises an inorganic porous carrier charged with a transition metal having an atomic number from the series 23 to 29, 41 to 47 and 73 to 79, in elementary form or in oxide form, or with a combination of at least two of the said materials.
    Type: Grant
    Filed: March 25, 1983
    Date of Patent: December 17, 1985
    Assignee: U.S. Philips Corporation
    Inventor: Wiggert Kroontje
  • Patent number: 4455998
    Abstract: There is provided a solar collector comprising an evacuated transparent envelope having an absorber arranged therewithin. A duct containing a heat-transport medium is arranged at least partially within such envelope and is so associated with the absorber that heat derived from incident solar radiation is transferred to the heat-transport medium in the duct during operation. A reversible heatable hydrogen getter consisting of a partial metal hydride is positioned in the envelope, together with a fully hydrogenized metal hydride thermally more stable and having a higher affinity for oxygen than the partial hydride.
    Type: Grant
    Filed: November 13, 1981
    Date of Patent: June 26, 1984
    Assignee: U.S. Philips Corporation
    Inventors: Wiggert Kroontje, Gijsbert Kuus
  • Patent number: 3958145
    Abstract: A high pressure mercury vapour discharge lamp having a discharge vessel provided with electrodes between which the discharge is maintained during operation and comprising a quantity of rare gas as a starting gas and furthermore between 0.5 and 25 mg of mercury and between 1 and 20 .mu.g mol of at least one of the halides of tin (with the exception of fluoride) per cubic cm of contents of the discharge vessel. To decrease the colour temperature of the radiation emitted by the lamp the discharge vessel is furthermore provided with at least one of the halides of lithium (with the exception of fluoride), while up to a maximum of 50 mol % of lithium halide may be replaced by sodium halide.
    Type: Grant
    Filed: February 14, 1974
    Date of Patent: May 18, 1976
    Assignee: U.S. Philips Corporation
    Inventors: Alexander Gray Jack, Wiggert Kroontje