Patents Assigned to CDF, Inc.
  • Sewer line restriction alarm placed in clean out plug
    Patent number: 5006833
    Abstract: A restricted flow alert for use in the access arm of the main clean-out plug location in a commercial or residential sewage system includes a diaphragm which moves in response to the presence of to close a switch and actuate an alarm. A pneumatic time delay prevents the alarm from being actuated in response to transient flow conditions in the sewer line and allows operation of the alarm at any physical orientation relative to the axis of the body of the restricted flow alert.
    Type: Grant
    Filed: July 25, 1989
    Date of Patent: April 9, 1991
    Assignee: CDF, Inc.
    Inventors: Edward D. Marlowe, Christian P. Marlowe