Patents by Inventor Charles A. Kirklen

Charles A. Kirklen 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: 3987390
    Abstract: The radio frequency resistance between a pair of conductive elements, for example, adjacent pipe sections of a pipeline, which are coupled together through an insulator, may be determined by contacting each pipe section with one of a pair of probes or electrodes connected across the output of a radio frequency oscillator which is coupled to the input of a rectifier and filter circuit. The probes are connected across the oscillator output through a resistor which insures that the direct current output of the rectifier is directly proportional to the RF resistance between the pipe sections. The output of the rectifier is coupled to a meter through an operational amplifier. The meter, which provides a direct readout of the resistance being measured, may be provided with a current limiting circuit which protects the meter from excessive DC current. Calibrating means may be provided to enable adjustment of the gain of the operational amplifier for resistance readings within several ranges.
    Type: Grant
    Filed: April 29, 1974
    Date of Patent: October 19, 1976
    Assignee: Sun Oil Company (Delaware)
    Inventors: Charles A. Kirklen, Charles F. Rhodes, Jr.