Patents by Inventor Adoniram J. Wells

Adoniram J. Wells 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).

  • Dosimeter having a low air flow rate
    Patent number: 4257746
    Abstract: An improved dosimeter having a low air flow rate for monitoring working areas in which air is pumped through the dosimeter at a controlled constant low rate of flow and any particles or vapors in the air are collected on a filter, a variable drive pump having an inlet and an outlet is connected to the filter and is driven by an electric motor and controlled by a feed back circuit of an integrator and an amplifier and the pump maintains a constant flow of air through the dosimeter; in operation of the dosimeter the integrator receives a signal from a pressure switch that detects changes in the flow of the air stream through the dosimeter by a change in a pressure drop of the air which is being pumped through an orifice;The improvement is the use of an adjustable by-pass valve connected in parallel with the variable drive pump in such a manner that regulated quantities of air from the outlet of the pump are recycled to the inlet of the pump thereby allowing the pump to provide a constant low flow rate of air;In
    Type: Grant
    Filed: October 2, 1978
    Date of Patent: March 24, 1981
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Adoniram J. Wells