Patents by Inventor Marlin D. Westra

Marlin D. Westra 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).

  • Method and apparatus for measuring leakage to ground
    Patent number: 4352058
    Abstract: Leakage current to ground from accessible locations on single phase electrical equipment is measured by powering the equipment through an isolation transformer and measuring the current flowing between the two power input terminals of the equipment under test via accessible locations on the equipment.
    Type: Grant
    Filed: February 1, 1980
    Date of Patent: September 28, 1982
    Assignee: Sencore, Inc.
    Inventor: Marlin D. Westra
  • Method and instrument for testing the operating characteristics of a capacitor
    Patent number: 4267503
    Abstract: Dielectric absorption in a capacitor is detected by making a first measurement of the capacitance of the capacitor, then charging the capacitor to its rated voltage, then discharging the capacitor, and then promptly making a second measurement of the capacitance of the capacitor. If the second measurement indicates a capacitance value less than that indicated by the first measurement, the capacitor exhibits dielectric absorption.
    Type: Grant
    Filed: November 2, 1979
    Date of Patent: May 12, 1981
    Inventor: Marlin D. Westra
  • Inductance meter
    Patent number: 4258315
    Abstract: A direct reading inductance meter applies linearly increasing ramp current pulses to a coil under test and compares the voltage developed across the coil during occurrence of the pulses with the voltage developed across the coil while a steady state current is applied to the coil thereby to provide an output voltage having a value directly related to the inductance of the coil.
    Type: Grant
    Filed: December 21, 1978
    Date of Patent: March 24, 1981
    Assignee: Sencore, Inc.
    Inventor: Marlin D. Westra
  • Channel frequency analyser
    Patent number: 4128808
    Abstract: The percentage deviation of citizen band transmitter channel frequencies from the standard channel frequencies is determined by counting the difference between the number of cycles in the transmitted and standard frequencies during a period of 0.37 second, the number counted being mathematically related to the percentage deviation by the same factor for all channel frequencies.
    Type: Grant
    Filed: November 4, 1976
    Date of Patent: December 5, 1978
    Assignee: Sencore, Inc.
    Inventor: Marlin D. Westra
  • Display circuit for battery powered digital meter
    Patent number: 3990008
    Abstract: A digital meter incorporates a circuit which senses the input voltage and automatically energizes a digital readout device only if the input voltage is greater than a predetermined absolute value.
    Type: Grant
    Filed: March 12, 1975
    Date of Patent: November 2, 1976
    Assignee: Sencore, Inc.
    Inventor: Marlin D. Westra