Patents by Inventor Dennis L. Belt

Dennis L. Belt 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: 6889121
    Abstract: The invention provides a computer implemented method to automate the calibration of the drive voltage waveform of a solenoid operated valve. An initial estimate of valve electromagnetic parameters and valve closure point is derived and the drive voltage waveform is created based in part on circuit constraints and the parameters and valve closure point. The drive voltage waveform is applied to the valve coil and the coil current feedback is obtained and used to update the initial estimate. This process is repeated until the coil current feedback meets predetermined criteria. The electromagnetic parameters include the L/R ratio of the valve during the pull-in time and decay time, the valve back emf during the pull-hold time, and the average resistance during hold when current is steady. The closure point is used to anchor the drive voltage waveform and is adjusted at a slower rate than the other parameters.
    Type: Grant
    Filed: March 5, 2004
    Date of Patent: May 3, 2005
    Assignee: Woodward Governor Company
    Inventors: Kamran Eftekhari Shahroudi, David J. Peterson, Dennis L. Belt