Patents by Inventor Karl L. Grafwallner

Karl L. Grafwallner 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: 4839566
    Abstract: An electric lamp for the photopolymerization of dental materials is supplied with constant electric power so that constant light output is obtained. The control circuit used to this end operates with a triac (3) connected between an a.c. voltage supply (2) and the lamp (1), said triac being controlled by signal values stored in a read-only memory of a microprocessor (4). Said stored values are respectively allocated to pairs of instantaneous values of lamp current and lamp voltage, the instantaneous values being detected in each cycle of the a.c. supply voltage and being utilized to address the read-only memory.
    Type: Grant
    Filed: February 19, 1987
    Date of Patent: June 13, 1989
    Assignee: ESPE Stiftung and Co. Produktions-und Vertriebs KG
    Inventors: Wolf-Dietrich Herold, Karl L. Grafwallner, Michael Keller
  • Patent number: 4571665
    Abstract: In an apparatus for treating dental materials with radiation of a selected spectral range, a receptacle accommodating the material to be treated is surrounded by one or a plurality of fluorescent tubes. The maximum emission of the fluorescent tubes is about 460 nm. The receptacle which accommodates the dental material during the irradiation process is preferably hermetically sealed and is made of a material that is transparent to the radiation.
    Type: Grant
    Filed: March 11, 1983
    Date of Patent: February 18, 1986
    Assignee: ESPE Fabrik pharmazeutischer Praeparate GmbH
    Inventors: Wolf-Dietrich Herold, Karl L. Grafwallner, Michael Keller
  • Patent number: 4538070
    Abstract: An apparatus for treating dental prosthetic parts includes a lamp, a reflector, a filter and an optical wave guide to project radiation of a selected spectral range onto a location of treatment. When an object is placed at this location, it actuates an infrared proximity switch which turns on the lamp for at least a predetermined period of time. A protective pane is disposed in front of the lamp and location of treatment which absorbs the selected spectral range but transmits other visible light to avoid glaring of an operator. The portion of the apparatus beneath the location of treatment includes a plate which is also absorptive in the selected spectral range to avoid disturbing reflections, and is replaceable since it may become contaminated by dental material dropping onto it and curing there.
    Type: Grant
    Filed: June 3, 1983
    Date of Patent: August 27, 1985
    Assignee: ESPE Fabrik pharmazeutischer Praeparate GmbH
    Inventors: Wolf-Dietrich Herold, Karl L. Grafwallner, Michael Keller
  • Patent number: 4412134
    Abstract: An apparatus for treating, particularly bleaching, dental objects, such as dentures or parts thereof, made of synthetic material includes a support disposed in a drawer for receiving the objects and a lamp disposed above the drawer for emitting radiation in a spectral range (approximately 400 to 500 nm) suitable for the bleaching process. An upper reflector surrounding the lamp reflects from the total radiation emitted by the lamp mainly the portion lying within the said spectral range while it transmits the remaining radiation to the outside. An inner surface of the drawer forms a lower reflector. The support also consists of reflective material and has a central semi-spherical projection to ensure that the object positioned on the support so as to surround the projection is irradiated from all sides.In another embodiment, the support for the dental object is made of glass, and two lamps each surrounded by a reflector are used to irradiate the object from above and below.
    Type: Grant
    Filed: July 15, 1981
    Date of Patent: October 25, 1983
    Assignee: ESPE Fabrik Pharmazeutischer Praeparate GmbH
    Inventors: Wolf-Dietrich Herold, Karl L. Grafwallner, Michael Keller