Patents Assigned to Joseph N. Nelson
  • Air filter gauge
    Patent number: 4033733
    Abstract: A gauge detecting the presence of a restriction placed upon an air stream passing through a filter in connection with an internal combustion engine, said gauge including a linear indicator to show the relative restriction present in the filter and including an indicator to show that the filter requires cleaning or replacement.
    Type: Grant
    Filed: February 23, 1976
    Date of Patent: July 5, 1977
    Assignee: Joseph N. Nelson
    Inventor: Richard D. Nelson