Patents by Inventor Hermanus S. J. Altena

Hermanus S. J. Altena 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: 6327784
    Abstract: The invention relates to a method of manufacturing a cutting member (3). According to the method, a single side 9 of a carrier 1 of the cutting member is provided with an auxiliary layer (11). The carrier is provided with a cutting edge (7) by means of an electrochemical machining device (19), an electrode (21) of the electrochemical machining device being arranged on a side (15) of the carrier remote from the auxiliary layer. According to the invention, the auxiliary layer is provided as far as the cutting edge to be provided on the carrier, and, after the cutting edge has been provided on the carrier, the auxiliary layer is maintained on the carrier as a layer which is functional for the cutting member. In this manner, the auxiliary layer has a double function and is thus utilized in a better way. In a preferred embodiment, the auxiliary layer mainly comprises SiO2 and has a thickness below 200 nm, preferably below 100 nm.
    Type: Grant
    Filed: December 22, 1999
    Date of Patent: December 11, 2001
    Assignee: U.S. Philips Corporation
    Inventors: Hermanus S. J. Altena, Maarten Brussee, Foppe Kramer, Johan Pragt
  • Patent number: 6312584
    Abstract: An apparatus for electrochemically machining of a workpiece by means of an electrode has an actuator for setting a gap between the electrode and the workpiece. The apparatus further has a channel for flushing the gap with an electrolyte and a container for containing the electrolyte. Power cords and are provided for feeding an electric current I supplied by a power supply through the electrolyte in the gap. Near the gap an antenna is provided to pick up electromagnetic waves radiated from the gap. The antenna is connected to a band-pass filter which passes signals in a frequency band of 40 to 100 MHz to a level detector. The level detector compares the amplitude of the filtered signal with a threshold value and supplies a stop signal to the control unit when the amplitude exceeds the threshold value. The control unit is programmed to open a switch in the power supply in response to the stop signal.
    Type: Grant
    Filed: January 12, 1999
    Date of Patent: November 6, 2001
    Assignee: U.S. Philips Corporation
    Inventors: Hermanus S. J. Altena, Anjali K. De Silva
  • Patent number: 6214200
    Abstract: In a method for electrochemical machining, the working distance is set by contacting the workpiece with the electrode, increasing the distance between the workpiece and the electrode by a first distance, detecting whether the contact between the electrode and the workpiece is broken, and further increasing the distance between the workpiece and the electrode by a second distance. Owing to this method, very small working distances can be set with a limited risk of short-circuiting and flash-over.
    Type: Grant
    Filed: April 2, 1999
    Date of Patent: April 10, 2001
    Assignee: U.S. Philips Corporation
    Inventors: Hermanus S. J. Altena, Maarten Brussee, Anton M. Boorsma, Foppe Kramer
  • Patent number: 5904831
    Abstract: The invention relates to a method of forming one or more through-holes in a metal workpiece, such as shaving foils or shaving combs, by means of an electrochemical machining apparatus (ECM apparatus). To this end, the method is characterized in that, during machining, the workpiece is provided on a substrate of an electroconductive, electrochemically inert material, such as a noble metal (alloy), in particular a noble metal (alloy) which is predominantly composed of Pt. Preferably, the workpiece is clamped onto the substrate. By virtue of said measures, rounding of the edges between the holes formed and the surface of the workpiece, which is clamped down on the substrate during machining, is reduced substantially. This has a favorable effect on the formation of sharp cutting faces.
    Type: Grant
    Filed: September 4, 1997
    Date of Patent: May 18, 1999
    Assignee: U.S. Philips Corporation
    Inventors: Hermanus S. J. Altena, Maarten Brussee, Foppe Kramer