Patents by Inventor Robert L. Spaw

Robert L. Spaw 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: 5497332
    Abstract: This invention involves transducing and monitoring the power being delivered by an electric generator to a power bus by using a monitor which includes an embedded microprocessor in the memory of which are stored reference digital numbers that correspond to the generator's nominal power, and to the components of the nominal power including output power. The generator's voltage and current signals are sensed and then shaped for use by the microprocessor wherein they are digitized into a first set of digital numbers. Preferably, the first set of digital numbers is converted into pulse-width modulated (PWM) square-wave signals, which are demodulated into DC current signals that are indicative of the power and the components of power being delivered by the electric generator to its power bus. The microprocessor digitizes the square wave signals into a second set of digital numbers, and calculates from the first and from the second sets of digital numbers real time digital numbers.
    Type: Grant
    Filed: October 1, 1993
    Date of Patent: March 5, 1996
    Assignee: Automatic Terminal Information Systems, Inc.
    Inventors: Charles R. Allen, Robert L. Spaw
  • Patent number: 4170311
    Abstract: The level measuring system measures a variable level within a sensing area containing a mass of material. A sensing probe is positioned within the area and is coupled to the tank of an oscillating circuit through a switching network. A reference probe positioned in or near the sensing area is also coupled through the switching network to the tank of the oscillating circuit. The frequency of oscillation will depend upon a physical parameter of the mass of material within the immediate vicinity of sensing probe. Environmental conditions affecting the reactance of the sensing probe will equally affect the reference probe and therefore a change in the frequency produced by the sensing probe relative to the frequency produced by the reference probe will provide a true indication of the physical parameter being measured. Signal processing means are coupled to the oscillator for processing this frequency change.
    Type: Grant
    Filed: January 19, 1978
    Date of Patent: October 9, 1979
    Assignee: Automatic Terminal Information Systems, Inc.
    Inventor: Robert L. Spaw
  • Patent number: 3935970
    Abstract: A single length of insulated, stranded steel cable extends vertically through a bin or other material container and functions as a radiating antenna for an electrical signal transmitter. The reactance of the antenna, which varies as a function of the level of material in the container adjacent the antenna, is inductively linked to an oscillator circuit in the transmitter. The transmitter's signal which is altered in frequency with changes in the antenna's reactance is combined with that of a constant frequency reference signal. The frequency of the resulting difference signal is employed to form a remote indication of the material level and to provide control information for automatically maintaining or varying material levels.
    Type: Grant
    Filed: February 4, 1974
    Date of Patent: February 3, 1976
    Inventor: Robert L. Spaw