Patents by Inventor Aart J. Van Bekkum

Aart J. Van Bekkum 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: 5113690
    Abstract: An electromagnetic flowmeter comprises a pressure-resistant measurement tube made of a heat-resistant material and a stainless steel casing which surrounds the measurement tube. Disposed in a sealed space between these two parts is a magnetic device comprising at least pole pieces and windings, and one or more measuring electrodes are arranged in the measurement tube. To ensure effective sealing even at high temperatures by simple means, at least one end of the stainless steel casing is bent to form a concentric inner ring and a steel compensation ring surrounds the inside of the inner ring. The steel from which the compensation ring is made has a coefficient of thermal expansion which is between that of the material of the measurement tube and that of the stainless steel of the casing.
    Type: Grant
    Filed: September 14, 1990
    Date of Patent: May 19, 1992
    Assignee: Krohne AG
    Inventors: Petrus N. J. van Nistelrooij, Aart J. van Bekkum
  • Patent number: 4838127
    Abstract: Ultrasonic flow meter of the clamp-on type for the measurement of the flow rate of a liquid in a pipeline, provided with two piezoelectric transmitting-receiving transducers, each accommodated in a housing, which are clamped at both sides of the pipeline axially offset with respect to each other thereon and which alternately transmit ultrasonic pulses into the pipeline and receive them therefrom in order to determine the flow rate from the transit time of the source pulses in the upstream and downstream direction. The transducers each consist of a row of adjacent subtransducers, the pulse emission face of which row is coupled over its entire length in the axial direction to the pipe wall.
    Type: Grant
    Filed: September 25, 1987
    Date of Patent: June 13, 1989
    Assignee: Altometer, Produktiebedrijf Van Rheometron A.G.
    Inventors: Pieter Herremans, Christiaan J. Hoogendijk, Adriaan H. Boer, Aart J. Van Bekkum