Patents by Inventor Shri Sridhar

Shri Sridhar 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: 6353295
    Abstract: A lamp electronic ballast with a piezoelectric cooling fan. Use of ballast-driven lamps is limited in some lighting applications by thermal considerations. For example, the problem of heat removal from compact fluorescent lamps with integrated ballasts has limited their use. Similarly, the use of ballast-driven fluorescent lighting in high hat and other closed luminaire applications has been limited by thermal considerations. Thermal management of ballasts for such thermally sensitive applications is provided by a piezoelectric fan integrated with the ballast. The power to drive the fan may be obtained from the same AC line input that supplies the ballast, or from an AC ripple voltage present at the output of a rectifier in the ballast, or from the output of the ballast to the lamp, or from any suitable circuit location in the ballast. The fan maybe a membrane-type spot-cooler comprising a thin membrane carried by a frame mounted adjacent a hot spot.
    Type: Grant
    Filed: January 20, 1999
    Date of Patent: March 5, 2002
    Assignee: Philips Electronics North America Corporation
    Inventors: Shri Sridhar, Vivek Mehrotra, Juan Sabate, Gert W. Bruning, Nicolaas Bernardus Roozen
  • Patent number: 6118651
    Abstract: Anodized aluminum anode and cathode foils are interleaved in a stack separated by spacers saturated with electrolyte in an enclosure. The anode foils and cathode foils have tabs which protrude from the housing and are cold welded to leads outside the housing, where they are not exposed to electrolyte. This permits using copper leads, which can be soldered to traces on a printed circuit board. A flat capacitor can be fixed underneath a PCB or even used as the substrate for a circuit, resulting in high volume efficiencies and the possibility of using it as a heat sink for other components.
    Type: Grant
    Filed: December 24, 1997
    Date of Patent: September 12, 2000
    Assignee: Philips Electronics North America Corp.
    Inventors: Vivek Mehrotra, Jose Azevedo, Shri Sridhar