Patents by Inventor David Kelsall

David Kelsall 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).

  • Apparatus for power supply systems
    Publication number: 20050122652
    Abstract: There is disclosed a control apparatus (12) for a power supply system (2) operable at a fluctuating line voltage, the system further comprising an energy storage device (10), and the control apparatus further comprising a line voltage monitor (14) and an energy storage device controller (12), wherein the control apparatus is configured whereby the energy storage device is at least partly discharged if the line voltage falls below a first predetermined voltage and the energy storage device is at least partly charged if the line voltage exceeds a second predetermined voltage and in which the first predetermined voltage is substantially lower than the second predetermined voltage. A power supply system (12) incorporating such a control apparatus is disclosed, as is a method of control thereof.
    Type: Application
    Filed: October 3, 2002
    Publication date: June 9, 2005
    Inventors: Michael Richardson, David Kelsall
  • Inflatable flat roof theatre
    Patent number: D653352
    Type: Grant
    Filed: September 10, 2010
    Date of Patent: January 31, 2012
    Inventors: G. Eric Jacques, David Kelsall
  • Inflatable theatre
    Patent number: D656239
    Type: Grant
    Filed: September 10, 2010
    Date of Patent: March 20, 2012
    Inventors: G. Eric Jacques, David Kelsall
  • Inflatable theatre
    Patent number: D657887
    Type: Grant
    Filed: October 20, 2011
    Date of Patent: April 17, 2012
    Inventors: G. Eric Jacques, David Kelsall