Patents by Inventor David Durfee

David Durfee 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: 10483055
    Abstract: A programmable arc fault circuit interrupter (AFCI) is provided. The programmable AFCI includes a dual resistive shunt array for developing inputs to an analog front end which in turn develops trigger quantities for input to a programmable processor. The programmable processor determines if the trigger quantities, singularly, or in the aggregate, exceed predetermined thresholds. Determining the predetermined thresholds are exceeded the processor issues a trigger command to momentarily energize a delatching coil, thus removing AC mains power from a load.
    Type: Grant
    Filed: July 6, 2017
    Date of Patent: November 19, 2019
    Assignee: Tower Manufacturing Corp.
    Inventors: Victor V. Aromin, David Durfee, Petar Horvatic, Steven O'Connell
  • Publication number: 20180151311
    Abstract: A programmable arc fault circuit interrupter (AFCI) is provided. The programmable AFCI includes a dual resistive shunt array for developing inputs to an analog front end which in turn develops trigger quantities for input to a programmable processor. The programmable processor determines if the trigger quantities, singularly, or in the aggregate, exceed predetermined thresholds. Determining the predetermined thresholds are exceeded the processor issues a trigger command to momentarily energize a delatching coil, thus removing AC mains power from a load.
    Type: Application
    Filed: July 6, 2017
    Publication date: May 31, 2018
    Inventors: Victor V. Aromin, David Durfee, Petar Hovitec, Steven O'Connell
  • Patent number: 9416777
    Abstract: An electrochemical actuator drive system and method that provides for full control of an electrochemical pump system having at least three electrochemical actuators, including two valve actuators, and one pump actuator. The driving circuit is based on a standard H-bridge driving circuit wherein part of the circuit is shared among actuators. Because the system only needs to operate either the pump actuator or one of the valve actuators at any given time, part of the H-bridge driving circuit can be shared among the three actuators, thereby permitting the use of four half-bridge driving circuits.
    Type: Grant
    Filed: September 26, 2014
    Date of Patent: August 16, 2016
    Assignee: Becton, Dickinson and Company
    Inventors: Andrew Leonczyk, David Durfee, Roland Croteau, Prestor Saillant
  • Publication number: 20160090971
    Abstract: An electrochemical actuator drive system and method that provides for full control of an electrochemical pump system having at least three electrochemical actuators, including two valve actuators, and one pump actuator. The driving circuit is based on a standard H-bridge driving circuit wherein part of the circuit is shared among actuators. Because the system only needs to operate either the pump actuator or one of the valve actuators at any given time, part of the H-bridge driving circuit can be shared among the three actuators, thereby permitting the use of four half-bridge driving circuits.
    Type: Application
    Filed: September 26, 2014
    Publication date: March 31, 2016
    Applicant: Becton Dickinson and Company
    Inventors: Andrew Leonczyk, David Durfee, Roland Croteau, Prestor Saillant
  • Publication number: 20070197938
    Abstract: In one aspect, the invention provides a system for determining lower body strength of a subject. In one embodiment, the system includes an electronic device having a plurality of sensors distributed in a predetermined array and a frame coupled to the electronic device and configured to support the device to allow the subject to activate one sensor of the plurality of sensors.
    Type: Application
    Filed: December 14, 2006
    Publication date: August 23, 2007
    Inventors: WILLIAM TYSON, JOHN HEANEY, DANIEL LABY, DAVID DURFEE, DAVID BANKS, DANIEL BENJAMIN
  • Publication number: 20070172231
    Abstract: A rotor magnet driven optical shutter assembly with a permanent magnet rotor directly connected to and driving the rotation of an optical shutter blade, to alternately block or allow transmission of light through the shutter aperture. The rotor is cylindrical with optional center hole, is magnetized across its diameter, and rotates around a pivot bearing coaxial with its center axis. A stator is arranged around the rotor and is shaped so that, as the rotor rotates over its range of travel, the flux through the electromagnet drive coil core varies in magnitude and direction. A drive current through the electromagnet drive coil thus induces a torque to the rotor, to open or close the shutter blade. By driving the electromagnet drive coil with a controlled current waveform, the shutter aperture may be opened or closed (either quickly or slowly), held open/closed, or moved to any intermediate position, as desired.
    Type: Application
    Filed: January 26, 2006
    Publication date: July 26, 2007
    Applicant: Melles Griot, Inc.
    Inventor: David Durfee
  • Publication number: 20070025826
    Abstract: A locator/fastener has a first outer member with a precision-machined external body portion, a retention head protruding from a first end, and a multi-diameter throughbore. A fastener, which may take the form of a cap screw, floats in the throughbore of the locator with the threaded portion protruding from a second end of the locator. A receiver has an internal precision-machined surface which contacts the precision-machined body portion of the locator and a threaded bore which receives the protruding fastener. By separating the locating and fastening functions, a quick connect disconnect device is created which does not bind or gall. A hangar system allows a sub-base plate to be attached to a base using the locator-fastener disclosed herein.
    Type: Application
    Filed: August 29, 2005
    Publication date: February 1, 2007
    Inventor: David Durfee
  • Patent number: 5065990
    Abstract: A vise jaw system for a vise having a keyway that defines a horizontal datum surface and a vertical datum surface includes at least one removable jaw for selective attachment to the vise, the removable jaw having a bottom surface held in fixed relation to the horizontal datum surface and a front surface perpendicular to the horizontal datum surface. The removable jaw also includes a recess formed in at least the bottom surface of the removable jaw. At least one positioning plate is selectively attached to the removable jaw, the positioning plate having a bottom face contacting the horizontal datum surface and a rear face perpendicular to the horizontal datum surface. The positioning plate further includes a cleat fixed to the positioning plate adjacent to the bottom face of the positioning plate, the cleat having a shape sized for reception in the recess.
    Type: Grant
    Filed: December 31, 1990
    Date of Patent: November 19, 1991
    Assignee: Susan M. Durfee
    Inventor: David Durfee