Patents Assigned to Oel-Held GmbH
  • Dielectric fluid for the machining of metal by means of spark erosion
    Patent number: 6048474
    Abstract: A dielectric fluid for the machining of metal by spark erosion which contains saturated aliphatic hydrocarbons with a proportion of aromatic hydrocarbons which is lower than one percent in weight and to which an additive is added, wherein organic substances from the group of anthraquinone derivatives are added as the additive in a concentration of maximally one percent in weight.
    Type: Grant
    Filed: May 21, 1997
    Date of Patent: April 11, 2000
    Assignee: Oel-Held GmbH
    Inventors: Manfred Storr, Wilhelm Rehbein
  • Method and apparatus for the machining of metal by spark erosion
    Patent number: 5773782
    Abstract: A dielectric fluid for the machining of metal by spark erosion which contains saturated aliphatic hydrocarbons with a proportion of aromatic hydrocarbons which is lower than one percent in weight and to which an additive is added, wherein organic substances from the group of anthraquinone derivatives are added as the additive in a concentration of maximally one percent in weight.
    Type: Grant
    Filed: March 19, 1997
    Date of Patent: June 30, 1998
    Assignee: Oel-Held GmbH
    Inventors: Manfred Storr, Wilhelm Rehbein