Patents by Inventor William P. Keegan

William P. Keegan 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: 4061037
    Abstract: A mechanical pipette having a measuring piston that controls the volume of liquid drawn into the pipette reservoir and a substantially larger piston that assures that all of the liquid in the reservoir is expelled therefrom on a discharge stroke. On the discharge stroke, a valve is opened to admit air being compressed by the larger piston into the reservoir. Means are provided to adjust the displacement of the larger piston so as to control the pressure developed by the larger piston.
    Type: Grant
    Filed: September 20, 1976
    Date of Patent: December 6, 1977
    Inventor: William P. Keegan
  • Patent number: 3935734
    Abstract: A mechanical pipette having a fixed stroke for aspirating and discharging a predetermined volume of liquid into and from a reservoir. A measuring piston controls the volume of liquid drawn into the reservoir and a substantially larger piston assures that all of the liquid in the reservoir is expelled therefrom on a discharge stroke. On the discharge stroke, a mechanically actuated valve is opened to admit air being compressed by the substantially larger piston into the reservoir.
    Type: Grant
    Filed: February 26, 1975
    Date of Patent: February 3, 1976
    Inventor: William P. Keegan