Patents by Inventor ALEXANDRU RAJALA

ALEXANDRU RAJALA 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: 11356006
    Abstract: An electric machine includes a machine rotor circumscribed by a machine stator, and having a rotor shaft, rotor stack, and end cap which rotate about an axis. The end cap includes lobes equal in number to a number of pole pairs of the machine rotor. A position sensor assembly has a predetermined alignment with the machine rotor and stator. The sensor assembly includes a sensor rotor formed by the lobes and a sensor stator having a printed circuit board with conductive sine and cosine traces. Machine rotor rotation causes the sensor assembly to output an unmodulated sine and cosine signals to a controller, which then calculates a calibrated reference angle. A magnetic axis of an electrical phase of the machine is aligned with and bisects a peak of the sine trace. A direct axis of the machine rotor aligns with an edge of a lobe.
    Type: Grant
    Filed: January 28, 2020
    Date of Patent: June 7, 2022
    Assignee: GM Global Technology Operations LLC
    Inventors: Suresh Gopalakrishnan, Chandra S. Namuduri, Alexandru Rajala, Thomas W. Nehl, Xiaohui Du, Edward L. Kaiser
  • Publication number: 20210234447
    Abstract: An electric machine includes a machine rotor circumscribed by a machine stator, and having a rotor shaft, rotor stack, and end cap which rotate about an axis. The end cap includes lobes equal in number to a number of pole pairs of the machine rotor. A position sensor assembly has a predetermined alignment with the machine rotor and stator. The sensor assembly includes a sensor rotor formed by the lobes and a sensor stator having a printed circuit board with conductive sine and cosine traces. Machine rotor rotation causes the sensor assembly to output an unmodulated sine and cosine signals to a controller, which then calculates a calibrated reference angle. A magnetic axis of an electrical phase of the machine is aligned with and bisects a peak of the sine trace. A direct axis of the machine rotor aligns with an edge of a lobe.
    Type: Application
    Filed: January 28, 2020
    Publication date: July 29, 2021
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Suresh Gopalakrishnan, Chandra S. Namuduri, Alexandru Rajala, Thomas W. Nehl, Xiaohui Du, Edward L. Kaiser
  • Patent number: 11015564
    Abstract: A starter assembly includes a multi-phase brushless electric motor including a stator, a rotor disposed on a rotatable shaft, and a motor endcap disposed at a first end of the stator. An electronic commutator assembly includes a sensing circuit, a control electronics subassembly, a power electronics subassembly and a heat sink. The sensing circuit is disposed adjacent to the second end of the rotatable shaft. The control electronics subassembly, the power electronics subassembly and the heat sink are disposed on disk-shaped devices arranged in a stacked configuration orthogonal to the axis defined by the rotatable shaft. The control electronics subassembly is disposed adjacent to the sensing circuit, and the power electronics subassembly is disposed adjacent to the control electronics subassembly. The control electronics subassembly is interposed between the power electronics subassembly and the sensing circuit. The heat sink is disposed adjacent to the power electronics subassembly.
    Type: Grant
    Filed: April 24, 2018
    Date of Patent: May 25, 2021
    Assignee: GM Global Technology Operations LLC
    Inventors: Chandra S. Namuduri, Lei Hao, Alexandru Rajala, Thomas W. Nehl
  • Patent number: 10886817
    Abstract: A starter assembly includes a partial planetary gear set connected to a pinion gear slidable along a first axis. The starter also includes a motor casing housing a brushless electric motor and having a first bearing. The motor includes multi-phase stator and rotor assemblies arranged inside the casing concentrically relative to the first axis. The rotor assembly has a rotor with a shaft supported by the first bearing and connected to a sun gear engaging the gear set, and a rotor position and speed sensor target. The starter additionally includes a motor end-cap for mating with and enclosing the motor casing and having a second bearing supporting the shaft. The starter also includes an electronics cover with a power connector for mating with the end-cap and housing an electronic commutator assembly. The commutator assembly includes power electronics, and control processor electronics arranged between the end-cap and the power electronics.
    Type: Grant
    Filed: April 24, 2018
    Date of Patent: January 5, 2021
    Assignee: GM Global Technology Operations LLC
    Inventors: Chandra S. Namuduri, Lei Hao, Alexandru Rajala, Thomas W. Nehl
  • Patent number: 10677212
    Abstract: A method of controlled stopping an internal combustion engine having a stop-start mode and starter assembly includes detecting when the stop-start mode is active. The method also includes monitoring current rotational speed and position of the engine. The method additionally includes determining when the current rotational position is within a predetermined range of a target stop rotational position and the current rotational speed is less than a threshold rotational speed, and afterward energizing the starter assembly to engage the engine. The method also includes establishing a time delay following energizing the starter assembly to confirm engagement of the starter assembly with the engine. Furthermore, the method includes applying a torque by the starter assembly to stop the engine at the target stop position. A vehicle powertrain employing the engine equipped with the stop-start mode, the starter assembly, and an electronic controller configured to execute the method is also provided.
    Type: Grant
    Filed: May 1, 2018
    Date of Patent: June 9, 2020
    Assignee: GM Global Technology Operations LLC
    Inventors: Suresh Gopalakrishnan, Lei Hao, Chandra S. Namuduri, Paul S. Lombardo, Chunhao J. Lee, Alexandru Rajala, Neeraj S. Shidore, Farzad Samie, Norman K. Bucknor, Dongxu Li
  • Patent number: 10471820
    Abstract: A drivetrain system for a vehicle is described, and includes an internal combustion engine, a geartrain, an electric machine, a power take-off unit, and a driveline. The internal combustion engine is coupled to the geartrain via a disconnect clutch and a torque converter. The geartrain includes a transmission and a differential gearset, including an output member of the transmission coupled to an input member of the differential gearset. The input member of the differential gearset is coupled to a rotor of the electric machine and the power take-off unit. The differential gearset is coupled to first and second intermediate driveshaft members of the driveline to transfer propulsion power to vehicle wheels that are arranged in a front-wheel configuration.
    Type: Grant
    Filed: May 1, 2017
    Date of Patent: November 12, 2019
    Assignee: GM Global Technology Operations LLC
    Inventors: Derek F. Lahr, Farzad Samie, Norman K. Bucknor, Chunhao J. Lee, Dongxu Li, Chandra S. Namuduri, Alexandru Rajala
  • Publication number: 20190338742
    Abstract: A method of controlled stopping an internal combustion engine having a stop-start mode and starter assembly includes detecting when the stop-start mode is active. The method also includes monitoring current rotational speed and position of the engine. The method additionally includes determining when the current rotational position is within a predetermined range of a target stop rotational position and the current rotational speed is less than a threshold rotational speed, and afterward energizing the starter assembly to engage the engine. The method also includes establishing a time delay following energizing the starter assembly to confirm engagement of the starter assembly with the engine. Furthermore, the method includes applying a torque by the starter assembly to stop the engine at the target stop position. A vehicle powertrain employing the engine equipped with the stop-start mode, the starter assembly, and an electronic controller configured to execute the method is also provided.
    Type: Application
    Filed: May 1, 2018
    Publication date: November 7, 2019
    Applicant: GM Global Technology Operations LLC
    Inventors: Suresh Gopalakrishnan, Lei Hao, Chandra S. Namuduri, Paul S. Lombardo, Chunhao J. Lee, Alexandru Rajala, Neeraj S. Shidore, Farzad Samie, Norman K. Bucknor, Dongxu Li
  • Publication number: 20190323475
    Abstract: A starter assembly includes a partial planetary gear set connected to a pinion gear slidable along a first axis. The starter also includes a motor casing housing a brushless electric motor and having a first bearing. The motor includes multi-phase stator and rotor assemblies arranged inside the casing concentrically relative to the first axis. The rotor assembly has a rotor with a shaft supported by the first bearing and connected to a sun gear engaging the gear set, and a rotor position and speed sensor target. The starter additionally includes a motor end-cap for mating with and enclosing the motor casing and having a second bearing supporting the shaft. The starter also includes an electronics cover with a power connector for mating with the end-cap and housing an electronic commutator assembly. The commutator assembly includes power electronics, and control processor electronics arranged between the end-cap and the power electronics.
    Type: Application
    Filed: April 24, 2018
    Publication date: October 24, 2019
    Applicant: GM Global Technology Operations LLC
    Inventors: Chandra S. Namuduri, Lei Hao, Alexandru Rajala, Thomas W. Nehl
  • Publication number: 20190326790
    Abstract: A brushless electric motor includes a motor casing having a first bearing, a motor end-cap including a second bearing, a multi-phase stator assembly, and a rotor assembly having a rotor shaft. The shaft has a first end, a second end, and a knurled section therebetween. The shaft also has a first bearing surface proximate the first end and supported by the first bearing, a second bearing surface proximate the second end and supported by the second bearing, and a rotor position and speed sensor target. The shaft additionally has a sun gear integrated with the shaft proximate the first bearing surface for engaging a partial planetary gear set. The rotor assembly also includes a rotor lamination fixed to the shaft at the knurled section and having opposing first and second sides, and first and second end plates arranged on the respective first and second sides of the rotor lamination.
    Type: Application
    Filed: April 24, 2018
    Publication date: October 24, 2019
    Applicant: GM Global Technology Operations LLC
    Inventors: Lei Hao, Chandra S. Namuduri, Alexandru Rajala, Thomas W. Nehl, Suresh Gopalakrishnan, Avoki M. Omekanda
  • Publication number: 20190323473
    Abstract: A starter assembly includes a multi-phase brushless electric motor including a stator, a rotor disposed on a rotatable shaft, and a motor endcap disposed at a first end of the stator. An electronic commutator assembly includes a sensing circuit, a control electronics subassembly, a power electronics subassembly and a heat sink. The sensing circuit is disposed adjacent to the second end of the rotatable shaft. The control electronics subassembly, the power electronics subassembly and the heat sink are disposed on disk-shaped devices arranged in a stacked configuration orthogonal to the axis defined by the rotatable shaft. The control electronics subassembly is disposed adjacent to the sensing circuit, and the power electronics subassembly is disposed adjacent to the control electronics subassembly. The control electronics subassembly is interposed between the power electronics subassembly and the sensing circuit. The heat sink is disposed adjacent to the power electronics subassembly.
    Type: Application
    Filed: April 24, 2018
    Publication date: October 24, 2019
    Applicant: GM Global Technology Operations LLC
    Inventors: Chandra S. Namuduri, Lei Hao, Alexandru Rajala, Thomas W. Nehl
  • Patent number: 10189470
    Abstract: A vehicle propulsion system includes an engine and a first electric machine each configured to selectively provide torque to propel the vehicle. A second electric machine is coupled to the engine to provide torque to start the engine from an inactive state. A high-voltage power source is configured to power both of the first electric machine and the second electric machine over a high-voltage bus. A propulsion controller is programmed to start the engine using cranking torque output from the second electric machine powered by the high-voltage power source. The controller is also programmed to operate both of the first electric machine and the combustion engine to propel the vehicle in response to an acceleration demand greater than a threshold. The controller is further programmed to decouple the engine and propel the vehicle using the first electric machine in response to vehicle speed less than a speed threshold.
    Type: Grant
    Filed: August 17, 2016
    Date of Patent: January 29, 2019
    Assignee: GM Global Technology Operations LLC
    Inventors: Venkata Prasad Atluri, Peter Beller, Norman K. Bucknor, Tito R. Huffman, Derek F. Lahr, Chunhao J. Lee, Dongxu Li, Chandra S. Namuduri, Thomas W. Nehl, Madhusudan Raghavan, Alexandru Rajala, Farzad Samie, Neeraj S. Shidore
  • Patent number: 10017044
    Abstract: A powertrain system is described, and includes an internal combustion engine including a crankshaft and an electric machine including a rotatable shaft, wherein the rotatable shaft is coupled to a motor pulley. A torque converter includes an impeller and a pump, wherein the pump is coupled to an outer sheave. An off-axis mechanical drive system includes the outer sheave of the torque converter rotatably coupled to the motor pulley of the electric machine. The electric machine is coupled to the pump of the torque converter via the off-axis mechanical drive system, and the crankshaft is coupled to the pump of the torque converter via a clutch.
    Type: Grant
    Filed: May 9, 2017
    Date of Patent: July 10, 2018
    Assignee: GM Global Technology Operations LLC
    Inventors: Derek F. Lahr, Farzad Samie, Norman K. Bucknor, Chunhao J. Lee, Dongxu Li, Chandra S. Namuduri, Alexandru Rajala
  • Patent number: 10011023
    Abstract: An end-effector assembly includes a master boom, a frame rail coupled thereto, and at least one branch rail movably coupled to the frame rail by a swing branch lock. The swing arm is movably coupled to the at least one branch rail by a swing arm lock. Each of the swing branch lock and the swing arm lock further includes a clamp configured to movably secure the branch rail to the frame rail or the swing arm to the branch rail. A pivot shaft extends through the clamp and is configured to rotationally secure the clamp in place. A swing plate is secured to the pivot shaft and is configured for engagement with a configuration tool. A locking fastener extends through the swing plate and into the pivot shaft and is configured to lock and unlock the clamp in position.
    Type: Grant
    Filed: March 14, 2017
    Date of Patent: July 3, 2018
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Yhu-Tin Lin, Dooil Hwang, Jinglin Li, Alexandru Rajala
  • Publication number: 20180050685
    Abstract: A vehicle propulsion system includes an engine and a first electric machine each configured to selectively provide torque to propel the vehicle. A second electric machine is coupled to the engine to provide torque to start the engine from an inactive state. A high-voltage power source is configured to power both of the first electric machine and the second electric machine over a high-voltage bus. A propulsion controller is programmed to start the engine using cranking torque output from the second electric machine powered by the high-voltage power source. The controller is also programmed to operate both of the first electric machine and the combustion engine to propel the vehicle in response to an acceleration demand greater than a threshold. The controller is further programmed to decouple the engine and propel the vehicle using the first electric machine in response to vehicle speed less than a speed threshold.
    Type: Application
    Filed: August 17, 2016
    Publication date: February 22, 2018
    Inventors: Venkata Prasad Atluri, Peter Beller, Norman K. Bucknor, Tito R. Huffman, Derek F. Lahr, Chunhao J. Lee, Dongxu Li, Chandra S. Namuduri, Thomas W. Nehl, Madhusudan Raghavan, Alexandru Rajala, Farzad Samie, Neeraj S. Shidore
  • Patent number: 9866157
    Abstract: A transmission assembly has an integrated torque machine including a torque machine stator and a torque machine rotor. The torque machine rotor includes at least one set of rotor magnets. An integrated rotational position sensor is configured to monitor rotational position of the torque machine rotor in relation to the torque machine stator. The integrated rotational position sensor includes a sensor rotor element and a sensor stator element. The sensor rotor element includes at least one set of sensor rotor magnets. The sensor rotor element is positioned such that the at least one set of sensor rotor magnets are aligned with respect to a rotor pole of the at least one set of rotor magnets of the torque machine rotor. The sensor stator element is positioned such that the sensor stator element is aligned with a magnetic axis of the torque machine stator.
    Type: Grant
    Filed: September 15, 2015
    Date of Patent: January 9, 2018
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Suresh Gopalakrishnan, Chandra S. Namuduri, Lei Hao, Alexandru Rajala
  • Publication number: 20170326964
    Abstract: A drivetrain system for a vehicle is described, and includes an internal combustion engine, a geartrain, an electric machine, a power take-off unit, and a driveline. The internal combustion engine is coupled to the geartrain via a disconnect clutch and a torque converter. The geartrain includes a transmission and a differential gearset, including an output member of the transmission coupled to an input member of the differential gearset. The input member of the differential gearset is coupled to a rotor of the electric machine and the power take-off unit. The differential gearset is coupled to first and second intermediate driveshaft members of the driveline to transfer propulsion power to vehicle wheels that are arranged in a front-wheel configuration.
    Type: Application
    Filed: May 1, 2017
    Publication date: November 16, 2017
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Derek F. Lahr, Farzad Samie, Norman K. Bucknor, Chunhao J. Lee, Dongxu Li, Chandra S. Namuduri, Alexandru Rajala
  • Publication number: 20170326965
    Abstract: A powertrain system is described, and includes an internal combustion engine including a crankshaft and an electric machine including a rotatable shaft, wherein the rotatable shaft is coupled to a motor pulley. A torque converter includes an impeller and a pump, wherein the pump is coupled to an outer sheave. An off-axis mechanical drive system includes the outer sheave of the torque converter rotatably coupled to the motor pulley of the electric machine. The electric machine is coupled to the pump of the torque converter via the off-axis mechanical drive system, and the crankshaft is coupled to the pump of the torque converter via a clutch.
    Type: Application
    Filed: May 9, 2017
    Publication date: November 16, 2017
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Derek F. Lahr, Farzad Samie, Norman K. Bucknor, Chunhao J. Lee, Dongxu Li, Chandra S. Namuduri, Alexandru Rajala
  • Patent number: 9735634
    Abstract: A rotor for a permanent magnet synchronous machine that includes a rotor core structure. A first set of permanent magnets forms poles within the rotor core structure. Each pole includes a pair of permanent magnets from the first set of permanent magnets. A first set of apertures is formed in a first radial layer of the rotor core structure. Each pole includes a pair of apertures from the first set of apertures. The first set of permanent magnets is inserted within the first set of apertures. Each pair of permanent magnets within a pole cooperatively generates a magnetic field in a same direction within the pole. The magnetic field generated by a respective pair of magnets in a respective pole is opposite to a magnetic field generated by a pair of permanent magnets in an adjacent pole.
    Type: Grant
    Filed: July 22, 2014
    Date of Patent: August 15, 2017
    Assignee: GM Global Technology Operations LLC
    Inventors: Lei Hao, Thomas W. Nehl, Chandra S. Namuduri, Michael G. Reynolds, Alexandru Rajala
  • Patent number: 9657705
    Abstract: A powertrain and an electromechanical apparatus are disclosed. A ring gear is attached to a first distal end of a crankshaft such that the ring gear and the crankshaft are rotatable in unison about a longitudinal axis. A motor-generator includes a motor/generator shaft being rotatable about a first axis spaced from the longitudinal axis. A starter mechanism includes a first starter gear coupleable to the motor/generator shaft and rotatable about a second axis spaced from the longitudinal axis. The first starter gear is movable along the second axis between a first position engaging the ring gear such that torque is transferred from the motor/generator shaft through the first starter gear and the ring gear to the crankshaft to start the engine, and a second position disengaged from the ring gear to rotatably disconnect the starter mechanism from the ring gear.
    Type: Grant
    Filed: March 13, 2014
    Date of Patent: May 23, 2017
    Assignee: GM Global Technology Operations LLC
    Inventors: Alan G. Holmes, Michael G. Reynolds, Alexandru Rajala, Chandra S. Namuduri, Venkata Prasad Atluri
  • Publication number: 20170077848
    Abstract: A transmission assembly has an integrated torque machine including a torque machine stator and a torque machine rotor. The torque machine rotor includes at least one set of rotor magnets. An integrated rotational position sensor is configured to monitor rotational position of the torque machine rotor in relation to the torque machine stator. The integrated rotational position sensor includes a sensor rotor element and a sensor stator element. The sensor rotor element includes at least one set of sensor rotor magnets. The sensor rotor element is positioned such that the at least one set of sensor rotor magnets are aligned with respect to a rotor pole of the at least one set of rotor magnets of the torque machine rotor. The sensor stator element is positioned such that the sensor stator element is aligned with a magnetic axis of the torque machine stator.
    Type: Application
    Filed: September 15, 2015
    Publication date: March 16, 2017
    Inventors: SURESH GOPALAKRISHNAN, CHANDRA S. NAMUDURI, LEI HAO, ALEXANDRU RAJALA