Patents Assigned to William M. Willis, Jr.
  • Patent number: 4464929
    Abstract: A tire cap pressure gauge for mounting upon a tire valve stem and measuring tire pressure has a housing, a manually operated plunger extending axially through the housing, a spring extending about the plunger, a piston biased by the spring and having indicia, and a transparent insert member containing said spring, piston and plunger within the housing and having an internally threaded bore for mounting about the periphery of a threaded valve stem. The housing has multiple windows with indicia proximate thereto for viewing the translational position of the piston through the transparent insert member. Two embodiments show a lightweight, compact and easily assembled pressure measuring cap having sealless construction which utilizes close clearances and sharp corners to minimize leakage airflow. A small but insignificant amount of air leaks past the piston, providing an audible signal that the plunger is sufficiently depressed to provide an adequate pressure reading.
    Type: Grant
    Filed: September 21, 1981
    Date of Patent: August 14, 1984
    Assignees: William M. Willis, Sr., William M. Willis, Jr., Jerry W. Schwarz
    Inventor: William M. Willis