Patents by Inventor M. Rahman

M. Rahman 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).

  • Publication number: 20080100254
    Abstract: Methods and systems are provided for controlling synchronous machines. The method comprises generating a d-axis current command and a q-axis current command, producing a modified current command from the q-axis current command, converting the d-axis current command to a first voltage command, converting the modified current command to a second voltage command, and supplying the first and second voltage commands to the synchronous machine. The modified current command limits a terminal voltage generated by the permanent magnet machine.
    Type: Application
    Filed: October 25, 2006
    Publication date: May 1, 2008
    Inventors: Khwaja M. Rahman, Silva Hiti
  • Publication number: 20080058542
    Abstract: The present invention relates to a novel photoactive compounds that can be used in formulating photoresist compositions.
    Type: Application
    Filed: October 18, 2007
    Publication date: March 6, 2008
    Inventors: M. Rahman, Francis Houlihan
  • Patent number: 7332837
    Abstract: Methods and apparatus are provided for an axial electric motor. The apparatus comprises, a stator having coils thereon for producing a magnetic field, a rotor rotated by the magnetic field, an output shaft coupled to the rotor, and a ring incorporating a coolant channel circumferentially engaging the stator for absorbing heat and reaction torque from the stator. It is preferable that that the ring have inwardly extending teeth that mesh with the coils on the stator. The space between the teeth and the coils is preferably filled with a substantially solid thermally conductive material to transmit stator reaction torque to the teeth and cool the stator. The coils are preferably formed from a flat ribbon a portion of whose principal surface is perpendicular to the teeth. A supporting frame is desirably fixedly coupled to the ring and rotatably coupled to the output shaft.
    Type: Grant
    Filed: July 29, 2004
    Date of Patent: February 19, 2008
    Assignee: General Motors Corporation
    Inventors: Terence G. Ward, Khwaja M. Rahman, James M. Nagashima, Fabio Crescimbini, Federico Caricchi, Giorgio Lucchi
  • Publication number: 20080035556
    Abstract: The present invention provides a method of reducing metals in solutions of film forming resins and a related filter sheet.
    Type: Application
    Filed: October 17, 2007
    Publication date: February 14, 2008
    Inventors: Munirathna Padmanaban, M. Rahman
  • Patent number: 7279862
    Abstract: An apparatus includes a multi-phase inverter, a fault detector to indicate a detection of a fault, a sensor to provide a speed signal indicative of whether a speed of a PM motor is greater than a transition speed, and a controller. The controller is operable to apply either an open-circuit response or a short-circuit response to the multi-phase inverter. The open-circuit response is applied when the speed of the PM motor is greater than the transition speed and a fault is detected. The short-circuit response is applied when the speed of the PM motor is less than the transition speed and the fault is detected. The transition speed is either a fixed predetermined speed or an adjusted predetermined speed.
    Type: Grant
    Filed: August 4, 2006
    Date of Patent: October 9, 2007
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Brian Welchko, Jonathan B Huse, Silva Hiti, Brendan M. Conlon, Constantin C. Stancu, Khwaja M. Rahman, David Tang, William R. Cawthorne
  • Patent number: 7262536
    Abstract: Methods and apparatus are provided for an electric vehicle embodying an axial flux traction motor directly coupled to a wheel thereof. The fraction motor includes a stator having coils for producing a magnetic field, an annular rotor magnetically coupled to the stator and mechanically to an output shaft Permanent magnets of alternating polarity are mounted on the annular rotor. Magnetic shunts bridge a portion of the stator slots above the coils. The magnets are arranged in groups with group-to-group spacing exceeding magnet-to-magnet spacing. Adjacent edges of the magnets diverge. The method comprises, looking up d- and q-axis currents to provide the requested torque and motor speed for the available DC voltage, combining at least one of the d- and q-axis currents with a field weakening correction term, converting the result from synchronous to stationary frame and operating an inverter therewith to provide current to the coils of the motor.
    Type: Grant
    Filed: July 29, 2004
    Date of Patent: August 28, 2007
    Assignee: General Motors Corporation
    Inventors: Khwaja M. Rahman, Silva Hiti, Nitinkumar R. Patel, Terence G. Ward, James M. Nagashima, Fabio Crescimbini, Federico Caricchi
  • Publication number: 20070111138
    Abstract: The present invention relates to novel photoacid generators.
    Type: Application
    Filed: February 16, 2006
    Publication date: May 17, 2007
    Inventors: M. Rahman, Munirathna Padmanaban
  • Publication number: 20070015084
    Abstract: The present application relates to a compound of formula A-X-B, where (i) A-X-B form an ionic compound Ai Xi Bi where Ai and Bi are each individually an organic onium cation; and Xi is anion of the formula Q-R500—SO3? or (ii) A-X-B form a non-ionic compound Ac-Xc-Bc, where Ai, Bi, Q, R500, Ac, Bc, and Xc are defined herein. The compounds are useful as photoactive materials.
    Type: Application
    Filed: February 16, 2006
    Publication date: January 18, 2007
    Inventors: M. Rahman, Francis Houlihan, Munirathna Padmanaban, SangHo Lee, Ralph Dammel, David Rentkiewicz, Clement Anyadiegwu
  • Patent number: 7088077
    Abstract: A method of controlling an IPM machine having a salient rotor. Stator terminal signals are measured and rotated to obtain synchronous reference frame current signals. A rotor position is estimated based on an impedance generated using the rotor and included in the current signals. The estimated rotor position is used to control the machine. An alternator-starter system in which this method is used can provide high cranking torque and generation power over a wide speed range while providing operational efficiency.
    Type: Grant
    Filed: November 9, 2004
    Date of Patent: August 8, 2006
    Assignee: General Motors Corporation
    Inventors: James M. Nagashima, Khwaja M. Rahman, Nitinkumar R. Patel, Steven E. Schulz, Terence G. Ward, Stanley K. Fujii
  • Patent number: 7072345
    Abstract: A network switch includes an input layer to receive a data stream with a set of cells. Each cell includes data and a header to designate a destination device. The input layer includes a set of input layer circuits. A selected input layer circuit of the set of input layer circuits receives the data stream. The selected input layer circuit includes a set of queues corresponding to a set of destination devices. The selected input layer circuit is configured to assign a selected cell from the data stream to a selected queue of the set of queues. The selected queue corresponds to a selected destination device specified by the header of the selected cell. An intermediate layer includes a set of intermediate layer circuits, each intermediate layer circuit has a set of buffers corresponding to the set of destination devices.
    Type: Grant
    Filed: August 24, 2001
    Date of Patent: July 4, 2006
    Assignee: Raza Microelectronics, Inc
    Inventors: Kai-Yeung (Sunny) Siu, Brain Hang Wai Yang, Mizanur M. Rahman
  • Patent number: 7057371
    Abstract: A hybrid/electric vehicle including a battery system connected to a DC charger, an inverter coupled to the battery system, and an electric AC motor coupled to the inverter. The motor has first, second and third stator windings corresponding to first, second and third phases of the motor. Each stator winding has first and second leads, and the inverter has a plurality of switches that are connected to provide current to the stator windings at the first and second leads.
    Type: Grant
    Filed: April 19, 2004
    Date of Patent: June 6, 2006
    Assignee: General Motors Corporation
    Inventors: Brian Welchko, James M. Nagashima, Khwaja M. Rahman
  • Patent number: 7051421
    Abstract: An electric traction motor for a vehicle including a housing, a wound stator field located in the housing, a rotor magnetically interacting with the wound stator field, high energy magnets configured in the rotor, and low energy magnets configured in the rotor.
    Type: Grant
    Filed: May 8, 2003
    Date of Patent: May 30, 2006
    Assignee: General Motors Corporation
    Inventors: Francois J. Biais, Khwaja M. Rahman
  • Publication number: 20060110677
    Abstract: The present invention relates to a novel chemically amplified photoresist, which is sensitive to wavelengths between 300 nm and 100 nm, and comprises a) a novel polymer comprising a sulfone group pendant from a polymer backbone that is insoluble in an aqueous alkaline solution and comprises at least one acidic moiety protected with acid labile group, and b) a compound capable of producing an acid upon irradiation. The invention also relates to a process of imaging the novel positive photoresist composition.
    Type: Application
    Filed: November 22, 2004
    Publication date: May 25, 2006
    Inventors: Francis Houlihan, Ralph Dammel, Andrew Romano, Munirathna Padmanaban, M. Rahman
  • Publication number: 20060102554
    Abstract: The present invention provides a method of reducing metals in solutions of film forming resins and a related filter sheet.
    Type: Application
    Filed: November 12, 2004
    Publication date: May 18, 2006
    Inventors: Munirathna Padmanaban, M. Rahman
  • Patent number: 7046681
    Abstract: A network switch includes an input layer to receive a data stream with a set of cells. Each cell includes data and a header to designate a destination device. The input layer includes a set of input layer circuits. A selected input layer circuit of the set of input layer circuits receives the data stream. The selected input layer circuit includes a set of queues corresponding to a set of destination devices. The selected input layer circuit is configured to assign a selected cell from the data stream to a selected queue of the set of queues. The selected queue corresponds to a selected destination device specified by the header of the selected cell. An intermediate layer includes a set of intermediate layer circuits, each intermediate layer circuit has a set of buffers corresponding to the set of destination devices.
    Type: Grant
    Filed: August 24, 2001
    Date of Patent: May 16, 2006
    Assignee: Raza Microelectronics, Inc.
    Inventors: Kai-Yeung (Sunny) Siu, Brain Hang Wai Yang, Mizanur M. Rahman
  • Publication number: 20050271974
    Abstract: The present invention relates to novel photoacid generators.
    Type: Application
    Filed: June 8, 2004
    Publication date: December 8, 2005
    Inventors: M. Rahman, Woo-Kyu Kim, Munirathna Padmanaban, Sangho Lee
  • Publication number: 20050130058
    Abstract: The present invention relates to a novel photoresist composition sensitive to radiation in the deep ultraviolet and a process for imaging the composition. The photoresist composition comprises a) a novel polymer that is insoluble in an aqueous alkaline solution and comprises at least one acid labile group, and b) a compound capable of producing an acid upon irradiation. The novel polymer of the present invention comprises at least one unit with a bisester group, (—C(O)OWC(O)O—), attached on one side to a polymer backbone unit (A) comprising an aliphatic group, and attached on the other side to an adamantyl group. The invention also relates to the novel polymer and a novel monomer for obtaining the novel polymer.
    Type: Application
    Filed: December 11, 2003
    Publication date: June 16, 2005
    Inventor: M. Rahman
  • Patent number: 6864646
    Abstract: A multiple inverter system is powered from a common energy source such as a battery. First and second inverters are coupled to the common energy source and drive corresponding motors. First and second controllers provide pulse width modulated signals, modulated with respect to first and second clock signals, respectively, to the respective first and second inverters. A capacitor coupled between a power bus and a ground bus smoothes power bus ripples caused by simultaneous switching. To reduce the size needed for the capacitor, different modulation schemes, such as center based interleaved, and leading and lagging edge coincident, are used when both motors are in the motoring mode or both motors are in the regeneration mode. However, the same modulation scheme is used when one motor is in the motoring mode and the other motor is in the regeneration mode.
    Type: Grant
    Filed: February 14, 2003
    Date of Patent: March 8, 2005
    Assignee: General Motors Corporation
    Inventors: Khwaja M. Rahman, Silva Hiti, Scott D. Downer, Brian Welchko
  • Patent number: 6801387
    Abstract: To reduce the whirling air vortices which are normally formed at the disc tip, the outer edge of the disc surface may be gradually thinned down to a sharp tip. An alternative approach, the disc tip is gradually reduced in width and rounded at its outer edge. A flow obstruction may be incorporated in the shroud adjacent the edge of the disc tip. This obstruction may comprise a small substantially rectangular insert extending from the inner edge of the housing. Or, the inner surface of the portion of the housing adjacent the ends of the disc may incorporate grooves therein. These grooves, which are roughly herringbone in shape, and would have their center near either the edge of disc in a single disc environment or mid-way between the disc in a two disc environment.
    Type: Grant
    Filed: April 13, 2001
    Date of Patent: October 5, 2004
    Assignee: Seagate Technology LLC
    Inventor: Mohamed M. Rahman
  • Publication number: 20040160201
    Abstract: A multiple inverter system is powered from a common energy source such as a battery. First and second inverters are coupled to the common energy source and drive corresponding motors. First and second controllers provide pulse width modulated signals, modulated with respect to first and second clock signals, respectively, to the respective first and second inverters. A capacitor coupled between a power bus and a ground bus smoothes power bus ripples caused by simultaneous switching. To reduce the size needed for the capacitor, different modulation schemes, such as center based interleaved, and leading and lagging edge coincident, are used when both motors are in the motoring mode or both motors are in the regeneration mode. However, the same modulation scheme is used when one motor is in the motoring mode and the other motor is in the regeneration mode.
    Type: Application
    Filed: February 14, 2003
    Publication date: August 19, 2004
    Inventors: Khwaja M. Rahman, Silva Hiti, Scott D. Downer, Brian Welchko