Patents by Inventor David Alan Ashman

David Alan Ashman 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).

  • Auto-zeroing absolute pressure sensor
    Patent number: 9116060
    Abstract: One aspect provides a method including determining that an absolute pressure sensor is not submersed in a fluid; measuring an atmospheric pressure with the absolute pressure sensor to determine an offset pressure measurement; submersing the absolute pressure sensor in a fluid; and measuring pressure with the absolute pressure sensor; wherein a compensated pressure measurement of the fluid is determined. Other embodiments are disclosed.
    Type: Grant
    Filed: May 23, 2012
    Date of Patent: August 25, 2015
    Assignee: Hach Company
    Inventors: David Alan Ashman, Timothy Alan Higgins, Lawrence B. Marsh
  • AUTO-ZEROING ABSOLUTE PRESSURE SENSOR
    Publication number: 20130317763
    Abstract: One aspect provides a method including determining that an absolute pressure sensor is not submersed in a fluid; measuring an atmospheric pressure with the absolute pressure sensor to determine an offset pressure measurement; submersing the absolute pressure sensor in a fluid; and measuring pressure with the absolute pressure sensor; wherein a compensated pressure measurement of the fluid is determined. Other embodiments are disclosed.
    Type: Application
    Filed: May 23, 2012
    Publication date: November 28, 2013
    Applicant: HACH COMPANY
    Inventors: David Alan Ashman, Timothy Alan Higgins, Lawrence B. Marsh