Patents by Inventor Madhur M. Purohit

Madhur M. Purohit 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: 10873244
    Abstract: An electronic module is provided for a power tool having an electric motor. The module includes a printed circuit board (PCB) having a first surface and a second surface; first set of power switches mounted on the first surface of the PCB; second set of power switches mounted on the PCB and electrically coupled to the first power switches forming an inverter bridge circuit for driving the electric motor; a first heat sink surface-mounted on the first surface of the PCB and having a planar main body disposed over the first power switches; a module housing arranged to receive the PCB therein; and a second heat sink secured to the module housing in thermal communication with the first heat sink to transfer heat from the first power switches.
    Type: Grant
    Filed: September 19, 2017
    Date of Patent: December 22, 2020
    Assignee: Black & Decker Inc.
    Inventors: Madhur M. Purohit, Joshua M. Lewis, Marcell E. Coates, Michael D. Grove, Victor A. Dorado
  • Patent number: 10848034
    Abstract: An electronic module is provided for a power tool having an electric motor. The electronic module includes a printed circuit board (PCB) being substantially disc-shaped; power switches mounted on the PCB forming an inverter bridge circuit for driving the electric motor; a controller mounted on the PCB and configured to control a switching operation of the power switches; positional sensors mounted on the PCB substantially equidistantly from a center of the PCB within the control portion and in communication with the controller to provide positional signals related to a rotational position of the electric motor to the controller; and a module housing arranged to receive the PCB therein. The module housing includes a planar portion in parallel to the PCB and openings disposed in the planar portion angularly around a center of the module housing to receive the positional sensors therein.
    Type: Grant
    Filed: September 19, 2017
    Date of Patent: November 24, 2020
    Assignee: Black & Decker Inc.
    Inventors: Madhur M. Purohit, Joshua M. Lewis, Marcell E. Coates, Michael D. Grove, Victor A. Dorado
  • Patent number: 10786894
    Abstract: A power tool is provided including a tool housing and a brushless DC (BLDC) motor disposed within the tool housing. The motor includes a stator assembly and a rotor assembly having a rotor lamination stack mounted on a rotor shaft to rotate therewith. The power tool also includes a power module for driving the motor, which includes: a printed circuit board, power switches operatively connected to the motor disposed on a first surface of the printed circuit board, positional sensors disposed on a second surface of the printed circuit board around a periphery of a center portion of the printed circuit board, and a heat sink having a substantially planar surface facing the second surface of the printed circuit board and disposed between the motor and the printed circuit board. The heat sink includes a through-hole therein sized to axially expose the positional sensors in the direction of the motor.
    Type: Grant
    Filed: October 13, 2016
    Date of Patent: September 29, 2020
    Assignee: Black & Decker Inc.
    Inventors: Marcell E. Coates, Madhur M. Purohit, Timothy J. Seeley, Joshua M. Lewis, David J. Smith, Bryce A. Wells
  • Publication number: 20200274421
    Abstract: A power tool is provided, including a housing; an electric brushless DC motor disposed within the housing; and a power module disposed within the housing and electrically coupled to the motor. The power module includes a circuit board, a first set of power switches mounted on a first surface of the circuit board, a second set of power switches mounted on a second surface of the circuit board substantially opposite the first set of power switches and electrically coupled to the first set of power switches forming an inverter bridge circuit, power terminals arranged on a side edge of the circuit board and coupled to the output of the inverter bridge, a first heat sink mounted on the first surface of the circuit board covering the first set of power switches, and a second heat sink covering the first heat sink and at least portions of the power terminals.
    Type: Application
    Filed: May 11, 2020
    Publication date: August 27, 2020
    Inventors: Madhur M. Purohit, John B. Fogle, Michael D. Grove
  • Publication number: 20200227975
    Abstract: A power module for driving a motor is provided including a power circuit board, power switches operatively connected to the motor disposed on a first side of the circuit board, and positional sensors disposed on a side surface of the power circuit board facing the motor. The power circuit board includes a thermally-conductive core carrier layer, a first electrically-insulating layer disposed on a first surface of the core carrier layer and on which the power switches are mounted, and a second electrically-insulating layer disposed on a second surface of the core carrier layer and on which the positional sensors are mounted. The second electrically-insulating layer is etched to expose the conductive core layer on at least approximately 70% of a surface area of the second side of the circuit board.
    Type: Application
    Filed: January 13, 2020
    Publication date: July 16, 2020
    Inventors: Madhur M. Purohit, Michael D. Grove, Joel D. Sayles
  • Patent number: 10693344
    Abstract: A power tool is provided, including a housing; an electric brushless DC motor disposed within the housing; and a control unit disposed within the housing and electrically coupled to the motor. The control unit includes a circuit board, a first set of power switches mounted on a first surface of the circuit board, a second set of power switches mounted on a second surface of the circuit board substantially opposite the first set of power switches and electrically coupled to the first set of power switches forming an inverter bridge circuit, power terminals arranged on a side edge of the circuit board and coupled to the output of the inverter bridge, and a heat sink mounted on the first surface of the circuit board covering the first set of power switches.
    Type: Grant
    Filed: December 17, 2015
    Date of Patent: June 23, 2020
    Assignee: Black & Decker Inc.
    Inventors: Madhur M. Purohit, John B. Fogle, Michael D. Grove
  • Patent number: 10500708
    Abstract: A power tool is provided including a gear case having a spindle, a motor case connected to a rear end of the gear case, a handle portion attached to a rear end of the motor case, and a motor housed inside the motor case. The motor includes a stator, a rotor rotationally arranged inside the stator, and a fan in rotational connection with the rotor. At least one air intake is arranged at least one of the motor case or the handle portion near the rear end of the motor case. A power module including power switches and a heat sink is housed in at least one of the motor case or the handle portion near the rear end of the motor case such that rotation of the fan causes air flow to enter through the air intake and flow near the heat sink and through the motor.
    Type: Grant
    Filed: October 13, 2016
    Date of Patent: December 10, 2019
    Assignee: Black & Decker Inc.
    Inventors: Joseph P. Kelleher, William F. Gallagher, Sean R. Templeton, Mark R. Poetzl, Seth M. Robinson, Marcell E. Coates, Madhur M. Purohit, Timothy J. Seeley, Joshua M. Lewis
  • Publication number: 20190058373
    Abstract: An electric brushless DC motor is provided including an outer rotor assembly having a metallic rotor body, rotor magnets mounted within an inner surface of the rotor body, and a molded structure formed within the rotor body. The molded structure includes at least one of: a main body formed on inner surface of the rotor body to securely cover and retain the rotor magnets on the inner surface of the rotor body, an axial fan formed at an end of the rotor body opposite the rotor magnets, and/or a sense magnet mount formed at approximately a radial center portion of the axial fan.
    Type: Application
    Filed: October 24, 2018
    Publication date: February 21, 2019
    Applicant: Black & Decker Inc.
    Inventors: John B. Fogle, Colin M. Crosby, David J. Smith, Merritt J. Tennison, Madhur M. Purohit
  • Patent number: 10193417
    Abstract: An electric brushless DC motor is provided including an outer rotor assembly having a metallic rotor body, rotor magnets mounted within an inner surface of the rotor body, and a molded structure formed within the rotor body. The molded structure includes a main body formed on inner surface of the rotor body to securely cover and retain the rotor magnets on the inner surface of the rotor body, an axial fan formed at an end of the rotor body opposite the rotor magnets, and a sense magnet mount formed at approximately a radial center portion of the axial fan. Alternatively or additionally, the molded structure includes a radial member projecting inwardly from the main body towards a center of the outer rotor assembly, and a bearing support member having a substantially cylindrical shape in an axial direction of the outer rotor and supported by the at least one radial member.
    Type: Grant
    Filed: December 17, 2015
    Date of Patent: January 29, 2019
    Assignee: Black & Decker Inc.
    Inventors: John B. Fogle, Colin M. Crosby, David J. Smith, Merritt J. Tennison, Madhur M. Purohit
  • Publication number: 20180083510
    Abstract: An electronic module is provided for a power tool having an electric motor. The module includes a printed circuit board (PCB) having a first surface and a second surface; first set of power switches mounted on the first surface of the PCB; second set of power switches mounted on the PCB and electrically coupled to the first power switches forming an inverter bridge circuit for driving the electric motor; a first heat sink surface-mounted on the first surface of the PCB and having a planar main body disposed over the first power switches; a module housing arranged to receive the PCB therein; and a second heat sink secured to the module housing in thermal communication with the first heat sink to transfer heat from the first power switches.
    Type: Application
    Filed: September 19, 2017
    Publication date: March 22, 2018
    Inventors: Madhur M. PUROHIT, Joshua M. LEWIS, Marcell E. COATES, Michael D. GROVE, Victor A. DORADO
  • Publication number: 20180084646
    Abstract: An electronic module is provided for a power tool having an electric motor. The electronic module includes a printed circuit board (PCB) being substantially disc-shaped; power switches mounted on the PCB forming an inverter bridge circuit for driving the electric motor; a controller mounted on the PCB and configured to control a switching operation of the power switches; positional sensors mounted on the PCB substantially equidistantly from a center of the PCB within the control portion and in communication with the controller to provide positional signals related to a rotational position of the electric motor to the controller; and a module housing arranged to receive the PCB therein. The module housing includes a planar portion in parallel to the PCB and openings disposed in the planar portion angularly around a center of the module housing to receive the positional sensors therein.
    Type: Application
    Filed: September 19, 2017
    Publication date: March 22, 2018
    Inventors: Madhur M. PUROHIT, Joshua M. LEWIS, Marcell E. COATES, Michael D. GROVE, Victor A. DORADO
  • Publication number: 20180034346
    Abstract: A power tool is provided including a housing, a brushless DC motor housed inside the housing, and a control unit housed inside the housing for controlling an operation of the brushless DC motor. The control unit includes a potting boat having an open portion, a circuit board received within the potting boat through the open portion, power switching elements mounted on the circuit board, a potting compound receiving within the potting boat to substantially surround the circuit board, and a heat sink in thermal communication with the power switching elements. The heat sink has a surface exposed outside the potting compound through the open portion of the potting boat.
    Type: Application
    Filed: October 10, 2017
    Publication date: February 1, 2018
    Applicant: Black & Decker Inc.
    Inventors: Madhur M. Purohit, Shailesh P. Waikar, Marcell E. Coates
  • Patent number: 9812930
    Abstract: A power tool is provided including a housing; a brushless DC motor housed inside an upper body of the housing; a control unit housed inside a handle of the housing, the control unit comprising a micro-controller mounted over a control circuit board; and a variable-speed switch assembly including a main body mounted directly on a surface of the control circuit board, a trigger, a plunger linearly movable with the trigger with respect to the main body, a speed-sensing mechanism housed inside the main body and coupled to the plunger to generate a variable-speed voltage signal based on the position of the plunger, and at least one output pin connecting the speed-sensing mechanism of the variable-speed switch assembly directly to at least one conductive track on the control circuit board to provide the variable-speed voltage signal to the micro-controller via the at least one conductive track.
    Type: Grant
    Filed: April 1, 2016
    Date of Patent: November 7, 2017
    Assignee: Black & Decker Inc.
    Inventors: Madhur M. Purohit, Shailesh P. Waikar, Marcell E. Coates
  • Publication number: 20170106522
    Abstract: A power tool is provided including a tool housing and a brushless DC (BLDC) motor disposed within the tool housing. The motor includes a stator assembly and a rotor assembly having a rotor lamination stack mounted on a rotor shaft to rotate therewith. The power tool also includes a power module for driving the motor, which includes: a printed circuit board, power switches operatively connected to the motor disposed on a first surface of the printed circuit board, positional sensors disposed on a second surface of the printed circuit board around a periphery of a center portion of the printed circuit board, and a heat sink having a substantially planar surface facing the second surface of the printed circuit board and disposed between the motor and the printed circuit board. The heat sink includes a through-hole therein sized to axially expose the positional sensors in the direction of the motor.
    Type: Application
    Filed: October 13, 2016
    Publication date: April 20, 2017
    Inventors: Marcell E. Coates, Madhur M. Purohit, Timothy J. Seeley, Joshua M. Lewis, David J. SMITH, Bryce A. WELLS
  • Publication number: 20170106521
    Abstract: A power tool is provided including a gear case having a spindle, a motor case connected to a rear end of the gear case, a handle portion attached to a rear end of the motor case, and a motor housed inside the motor case. The motor includes a stator, a rotor rotationally arranged inside the stator, and a fan in rotational connection with the rotor. At least one air intake is arranged at least one of the motor case or the handle portion near the rear end of the motor case. A power module including power switches and a heat sink is housed in at least one of the motor case or the handle portion near the rear end of the motor case such that rotation of the fan causes air flow to enter through the air intake and flow near the heat sink and through the motor.
    Type: Application
    Filed: October 13, 2016
    Publication date: April 20, 2017
    Inventors: Joseph P. Kelleher, William F. Gallagher, Sean R. Templeton, Mark R. Poetzl, Seth M. Robinson, Marcell E. Coates, Madhur M. Purohit, Timothy J. Seeley, Joshua M. Lewis
  • Publication number: 20160218589
    Abstract: A power tool is provided including a housing; a brushless DC motor housed inside an upper body of the housing; a control unit housed inside a handle of the housing, the control unit comprising a micro-controller mounted over a control circuit board; and a variable-speed switch assembly including a main body mounted directly on a surface of the control circuit board, a trigger, a plunger linearly movable with the trigger with respect to the main body, a speed-sensing mechanism housed inside the main body and coupled to the plunger to generate a variable-speed voltage signal based on the position of the plunger, and at least one output pin connecting the speed-sensing mechanism of the variable-speed switch assembly directly to at least one conductive track on the control circuit board to provide the variable-speed voltage signal to the micro-controller via the at least one conductive track.
    Type: Application
    Filed: April 1, 2016
    Publication date: July 28, 2016
    Applicant: Black & Decker Inc.
    Inventors: Madhur M. Purohit, Shailesh P. Waikar, Marcell E. Coates
  • Publication number: 20160181892
    Abstract: A power tool is provided, including a housing; an electric brushless DC motor disposed within the housing; and a control unit disposed within the housing and electrically coupled to the motor. The control unit includes a circuit board, a first set of power switches mounted on a first surface of the circuit board, a second set of power switches mounted on a second surface of the circuit board substantially opposite the first set of power switches and electrically coupled to the first set of power switches forming an inverter bridge circuit, power terminals arranged on a side edge of the circuit board and coupled to the output of the inverter bridge, and a heat sink mounted on the first surface of the circuit board covering the first set of power switches.
    Type: Application
    Filed: December 17, 2015
    Publication date: June 23, 2016
    Applicant: Black & Decker Inc.
    Inventors: Madhur M. Purohit, John B. Fogle, Michael D. Grove
  • Publication number: 20160181891
    Abstract: An electric brushless DC motor is provided including an outer rotor assembly having a metallic rotor body, rotor magnets mounted within an inner surface of the rotor body, and a molded structure formed within the rotor body. The molded structure includes a main body formed on inner surface of the rotor body to securely cover and retain the rotor magnets on the inner surface of the rotor body, an axial fan formed at an end of the rotor body opposite the rotor magnets, and a sense magnet mount formed at approximately a radial center portion of the axial fan. Alternatively or additionally, the molded structure includes a radial member projecting inwardly from the main body towards a center of the outer rotor assembly, and a bearing support member having a substantially cylindrical shape in an axial direction of the outer rotor and supported by the at least one radial member.
    Type: Application
    Filed: December 17, 2015
    Publication date: June 23, 2016
    Applicant: Black & Decker Inc.
    Inventors: John B. Fogle, Colin M. Crosby, David J. Smith, Merritt J. Tennison, Madhur M. Purohit
  • Patent number: 9318932
    Abstract: A power tool includes a brushless DC motor housed inside an upper body of the tool housing and a control unit housed inside a handle of the housing, the control unit including a micro-controller mounted on a control circuit board, a power unit electronically coupled to the micro-controller and mounted on a power circuit board arranged substantially parallel the control circuit board inside the handle, and a heat sink in thermal contact with the power unit. An input unit may be mounted directly on the control circuit board. An upper portion of the heat sink extending towards the upper body of the housing may include a tab protruding underneath a fan assembly of the motor to transfer heat from the power unit to the airflow created by the fan.
    Type: Grant
    Filed: June 14, 2011
    Date of Patent: April 19, 2016
    Assignee: Black & Decker Inc.
    Inventors: Madhur M. Purohit, Earl M. Ortt, Erik Ekstrom, Shailesh P. Waikar, Marcell E. Coates, Eric E. Hatfield
  • Publication number: 20140132093
    Abstract: A power tool includes a brushless DC motor housed inside an upper body of the tool housing and a control unit housed inside a handle of the housing, the control unit including a micro-controller mounted on a control circuit board, a power unit electronically coupled to the micro-controller and mounted on a power circuit board arranged substantially parallel the control circuit board inside the handle, and a heat sink in thermal contact with the power unit. An input unit may be mounted directly on the control circuit board. An upper portion of the heat sink extending towards the upper body of the housing may include a tab protruding underneath a fan assembly of the motor to transfer heat from the power unit to the airflow created by the fan.
    Type: Application
    Filed: June 14, 2011
    Publication date: May 15, 2014
    Applicant: Black & Decker Inc.
    Inventors: Madhur M. Purohit, Earl M. Ortt, Erik Ekstrom, Shailesh P. Waikar, Marcell E. Coates, Eric E. Hatfield