Patents by Inventor M. Imam

M. Imam 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: 8384292
    Abstract: Methods of protecting an electrical device, such as a ballast, from damage due to an inrush current, and devices incorporating such methods, are disclosed. A loss of input power received by the ballast is detected. In response, the ballast is entered into a standby mode. The ballast is able to remain in the standby mode for a standby period of time. The input power is monitored during the standby period of time to measure a start time. Measurement of the start time is triggered by the ballast receiving input power again. The ballast is entered into an active mode when the measured start time exceeds a protection time. The protection time corresponds to an amount of time needed for an inrush current to dissipate following input power again being received by the ballast, protecting the ballast from possible damage due to the inrush current.
    Type: Grant
    Filed: April 2, 2010
    Date of Patent: February 26, 2013
    Assignee: Osram Sylvania Inc.
    Inventors: Afroz M. Imam, Sivakumar Thangavelu
  • Patent number: 8373351
    Abstract: A driver circuit includes a plurality of switches, forming two switching legs, each of at least two switches and connected between two DC voltage buses. The switches are matched to form diagonal pairs. The driver circuit also includes a load circuit connecting the legs, with a first inductor connected between one leg's switches, and a second inductor connected between the other leg's switches, and lamp terminals between the inductors and in series with the second inductor. The driver circuit also includes a capacitor in parallel with the series-connected lamp terminals and the second inductor, and a control circuit connected to the plurality of switches. During a commutation period, a diagonal pair operates in a non-conductive state and the other in a conductive state, until a current through the first inductor reaches a predefined value. Then the other operates in a non-conductive state until the current through the first inductor reaches zero.
    Type: Grant
    Filed: December 8, 2010
    Date of Patent: February 12, 2013
    Assignee: OSRAM SYLVANIA Inc.
    Inventors: Sivakumar Thangavelu, Afroz M. Imam
  • Patent number: 8120272
    Abstract: A control circuit for a lamp. The control circuit is used in conjunction with an alternating current (AC) variable voltage power source to energize the lamp. The control circuit includes a voltage sensing component for sensing the voltage of an voltage input signal from the power source for energizing the lamp. The control circuit includes a controller configured to estimate a delay angle as a linear function of the sensed voltage. The control circuit includes an AC converter for modifying the voltage input signal according to the estimated delay angle to generate an AC voltage output signal having a constant root mean square voltage for energizing the lamp.
    Type: Grant
    Filed: September 30, 2008
    Date of Patent: February 21, 2012
    Assignee: Osram Sylvania Inc.
    Inventors: Afroz M. Imam, Sivakumar Thangavelu, Mustansir Kheraluwala
  • Publication number: 20110241550
    Abstract: Methods of protecting an electrical device, such as a ballast, from damage due to an inrush current, and devices incorporating such methods, are disclosed. A loss of input power received by the ballast is detected. In response, the ballast is entered into a standby mode. The ballast is able to remain in the standby mode for a standby period of time. The input power is monitored during the standby period of time to measure a start time. Measurement of the start time is triggered by the ballast receiving input power again. The ballast is entered into an active mode when the measured start time exceeds a protection time. The protection time corresponds to an amount of time needed for an inrush current to dissipate following input power again being received by the ballast, protecting the ballast from possible damage due to the inrush current.
    Type: Application
    Filed: April 2, 2010
    Publication date: October 6, 2011
    Applicant: OSRAM SYLVANIA INC.
    Inventors: Afroz M. Imam, Sivakumar Thangavelu
  • Publication number: 20110133664
    Abstract: A driver circuit includes a plurality of switches, forming two switching legs, each of at least two switches and connected between two DC voltage buses. The switches are matched to form diagonal pairs. The driver circuit also includes a load circuit connecting the legs, with a first inductor connected between one leg's switches, and a second inductor connected between the other leg's switches, and lamp terminals between the inductors and in series with the second inductor. The driver circuit also includes a capacitor in parallel with the series-connected lamp terminals and the second inductor, and a control circuit connected to the plurality of switches. During a commutation period, a diagonal pair operates in a non-conductive state and the other in a conductive state, until a current through the first inductor reaches a predefined value. Then the other operates in a non-conductive state until the current through the first inductor reaches zero.
    Type: Application
    Filed: December 8, 2010
    Publication date: June 9, 2011
    Applicant: OSRAM SYLVANIA INC.
    Inventors: Afroz M. Imam, Sivakumar Thangavelu
  • Patent number: 7944149
    Abstract: A ballast including an H-bridge type inverter for driving a lamp and a filter circuit that includes a buck inductor is disclosed. The buck inductor is a primary winding of a transformer, and a secondary winding of the transformer provides power to a controller of the ballast. The controller operates the inverter in various pre-ignition modes of operation such that prior to ignition, the open circuit voltage (OCV) (i.e., voltage across the lamp) and buck inductor current are controlled to transfer sufficient power from the primary of the transformer to the secondary winding of the transformer to power the controller. No switches of the inverter are turned on while there is a non-zero current through the filter circuit.
    Type: Grant
    Filed: May 12, 2009
    Date of Patent: May 17, 2011
    Assignee: Osram Sylvania Inc.
    Inventors: Afroz M. Imam, Sivakumar Thangavelu, Mustansir Kheraluwala
  • Publication number: 20100289421
    Abstract: A ballast including an H-bridge type inverter for driving a lamp and a filter circuit that includes a buck inductor is disclosed. The buck inductor is a primary winding of a transformer, and a secondary winding of the transformer provides power to a controller of the ballast. The controller operates the inverter in various pre-ignition modes of operation such that prior to ignition, the open circuit voltage (OCV) (i.e., voltage across the lamp) and buck inductor current are controlled to transfer sufficient power from the primary of the transformer to the secondary winding of the transformer to power the controller. No switches of the inverter are turned on while there is a non-zero current through the filter circuit.
    Type: Application
    Filed: May 12, 2009
    Publication date: November 18, 2010
    Applicant: OSRAM SYLVANIA Inc.
    Inventors: Afroz M. Imam, Sivakumar Thangavelu, Mustansir Kheraluwala
  • Publication number: 20100079077
    Abstract: A control circuit for a lamp. The control circuit is used in conjunction with an alternating current (AC) variable voltage power source to energize the lamp. The control circuit includes a voltage sensing component for sensing the voltage of an voltage input signal from the power source for energizing the lamp. The control circuit includes a controller configured to estimate a delay angle as a linear function of the sensed voltage. The control circuit includes an AC converter for modifying the voltage input signal according to the estimated delay angle to generate an AC voltage output signal having a constant root mean square voltage for energizing the lamp.
    Type: Application
    Filed: September 30, 2008
    Publication date: April 1, 2010
    Applicant: OSRAM SYLVANIA INC.
    Inventors: Afroz M. Imam, Sivakumar Thangavelu, Mustansir Kheraluwala
  • Publication number: 20070124057
    Abstract: A voice recognition method that is used for finding a street uses a database including information about a plurality of streets. The streets are characterized by respective street names and street types. A user provides a voice input for the street that the user tries to find. The voice input includes a street name and a street type. The street type is recognized by processing the voice input. Streets having the recognized street type are then selected from the database and a street name of at least one of the streets selected from the database is recognized by processing the voice input.
    Type: Application
    Filed: November 30, 2005
    Publication date: May 31, 2007
    Inventors: Ramon Prieto, Carsten Bergmann, William Lathrop, M. Imam, Gerd Gruchalski, Markus Mohrle
  • Publication number: 20050230009
    Abstract: A palladium-boron composition and methods of making and using same are provided. In one aspect, the invention comprises an alloy comprising palladium and boron, the boron being in solid solution in the palladium and the alloy having a two-phase structure, wherein each phase of the two-phase structure has the same crystal structure as the other phase and has a different set of lattice parameters from the other phase such that the palladium is greatly hardened by the presence of the smaller phase crystals within the spaces between the larger phase crystals. The composition is carefully prepared by a process wherein palladium and an amount of boron sufficient to place the boron in solid solution, but insufficient to combine with the palladium, are placed together and repeatedly are melted, cooled and turned over until sufficiently mixed.
    Type: Application
    Filed: August 23, 2004
    Publication date: October 20, 2005
    Inventors: Melvin Miles, M. Imam
  • Patent number: 5151407
    Abstract: Bulk form of superconducting materials are produced by pouring a melt a O.sub.2 -containing superconducting material into a heated mold, cooling the mold until solidification begins, removing the cast object from the mold, gradually cooling the cast object to prevent the development of thermal stresses, and then annealing the cast, cooled object to restore O.sub.2 to near equilibrium levels. The bulk form produced according to the present invention may be used as a sputtering target in the production of wires, or as a bulk form semiconductor.
    Type: Grant
    Filed: February 28, 1990
    Date of Patent: September 29, 1992
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Virgil Provenzano, Anand K. Singh, M. A. Imam, Kuntimadi Sadananda, William F. Henshaw
  • Patent number: 5104850
    Abstract: A high temperature superconducting coating of material oxide is produced by melting the metal oxide mixture, dipping a substrate, e.g. a platinum wire, in the metal oxide melt, withdrawing the substrate with a layer of metal oxide coated thereon, slowly cooling the metal oxide coating to avoid thermal shock and hot cracking, and post-annealing the metal oxide coating.
    Type: Grant
    Filed: February 28, 1990
    Date of Patent: April 14, 1992
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Virgil Provenzano, Anand K. Singh, M. A. Imam, Terry M. Tritt