Patents by Inventor Dan Tho Lu

Dan Tho Lu 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: 20190072449
    Abstract: Systems, methods, and devices for positioning, orienting, and/or aligning a stress sensor assembly are provided. Raw stress signals, which can correspond to stress in the target, can be generated by detecting a magnetic flux that travels through the target. The raw stress signals can be sensitive to an alignment of the sensor relative to the target. In order to minimize measurement error, the stress sensor can be properly aligned relative to the target prior to taking a stress measurement. Sensor alignment can involve adjusting a yaw, pitch, and/or roll of the sensor, measuring the raw stress signals, attenuating the detected magnetic flux, and measuring the raw stress signals again. When the stress sensor is properly aligned, a change in a size of a gap between the sensor and a surface of a target can result in approximately equal changes in the raw stress signal.
    Type: Application
    Filed: September 6, 2017
    Publication date: March 7, 2019
    Inventors: David Folkner, Dan Tho Lu, Lysle Turnbeaugh, Brian F. Howard, Trevor Cowan, Brian Bowlds, David O'Connor
  • Patent number: 10209147
    Abstract: A gap compensated torque sensing system and methods for using the same are provided. The system can include a sensor head in communication with a controller. The sensor head can contain a torque sensor and a proximity sensor coupled to the sensor head. The torque and proximity sensors can each sense magnetic fluxes passing through the target and a gap between the sensor head and the target. The controller can estimate torque applied to the target from magnetic fluxes sensed by the torque sensor. The controller can determine an improved gap measurement that is independent of electromagnetic properties of the target from magnetic fluxes sensed by the torque and proximity sensors. The estimated torque can be modified by the improved gap measurement to compensate for changes in magnetic properties of the target due to variations in the gap. In this manner, the accuracy of the torque measurements can be increased.
    Type: Grant
    Filed: August 11, 2017
    Date of Patent: February 19, 2019
    Assignee: Bently Nevada, LLC
    Inventors: Dan Tho Lu, Brian F. Howard, Pekka Tapani Sipila
  • Publication number: 20190049320
    Abstract: A gap compensated torque sensing system and methods for using the same are provided. The system can include a sensor head in communication with a controller. The sensor head can contain a torque sensor and a proximity sensor coupled to the sensor head. The torque and proximity sensors can each sense magnetic fluxes passing through the target and a gap between the sensor head and the target. The controller can estimate torque applied to the target from magnetic fluxes sensed by the torque sensor. The controller can determine an improved gap measurement that is independent of electromagnetic properties of the target from magnetic fluxes sensed by the torque and proximity sensors. The estimated torque can be modified by the improved gap measurement to compensate for changes in magnetic properties of the target due to variations in the gap. In this manner, the accuracy of the torque measurements can be increased.
    Type: Application
    Filed: August 11, 2017
    Publication date: February 14, 2019
    Inventors: Dan Tho Lu, Brian F. Howard, Pekka Tapani Sipila
  • Publication number: 20190041279
    Abstract: A system includes a magnetostrictive sensor. The magnetostrictive sensor includes a driving coil configured to receive a first driving current and to emit a first magnetic flux portion through a target and a second magnetic flux portion. The magnetostrictive sensor also includes a first sensing coil configured to receive the first magnetic flux portion and to transmit a signal based at least in part on the received first magnetic flux portion. The received first magnetic flux portion is based at least in part on a force on the target. The magnetostrictive sensor includes a magnetic shield disposed between the driving coil and the first sensing coil. The magnetic shield is configured to reduce the second magnetic flux portion received by the first sensing coil. The magnetic shield includes a composite with a conductive material and an insulating material, a metamaterial, or a mesh structure, or any combination thereof.
    Type: Application
    Filed: October 4, 2018
    Publication date: February 7, 2019
    Applicant: General Electric Company
    Inventors: Pekka Tapani Sipila, Lam Arthur Campbell, Dan Tho Lu
  • Patent number: 10184846
    Abstract: A system may include a first sensor and a second sensor. The first sensor may include a driving pole that includes a driving coil that receives a driving current and emits a magnetic flux portion through a structure. The first sensor may also include a sensing pole that may include a sensing coil that receives the magnetic flux portion and generate a first signal based at least in part on the received magnetic flux portion. The first signal is based at least in part on a force on the structure. The second sensor may be disposed on the driving pole and may generate a second signal representative of a distance between the driving pole and the structure. The system may also include a circuit that may adjust the first signal based on the second signal.
    Type: Grant
    Filed: August 31, 2016
    Date of Patent: January 22, 2019
    Assignee: General Electric Company
    Inventors: Dan Tho Lu, Lysle R. Turnbeaugh, David Erik Folkner
  • Patent number: 10185021
    Abstract: A method for aligning a sensor with a conductive material includes inducing a first magnetic flux in the conductive material to generate a first magnetic field state, and receiving a first signal at a first signal output level from a first detector and a second signal at a second signal output level from a second detector at the first magnetic field state. The method also includes inducing a second magnetic flux in the conductive material to generate a second magnetic field state, and receiving a third signal at a third signal output level from the first detector and a fourth signal at a fourth signal output level from the second detector at the second magnetic field state. Moreover, the method includes, based on changes in the signal output levels, adjusting a position of the sensor relative to the conductive target material to adjust the signal output levels to desired levels.
    Type: Grant
    Filed: December 14, 2016
    Date of Patent: January 22, 2019
    Assignee: General Electric Company
    Inventors: David Erik Folkner, Dan Tho Lu, Lysle Turnbeaugh, Brian Howard
  • Publication number: 20190017888
    Abstract: A temperature compensated torque sensing system and methods for using the same are provided. The system can include a sensor head in electrical communication with a controller. The sensor head can contain a torque sensor including a core, a driving coil and a sensing coil. The sensor head can also include a temperature sensor coupled to the sensor head. The torque sensor can be configured to measure torque applied to a selected portion of a target based upon magnetic flux passing through the target, while the temperature sensor can be configured to concurrently measure the target temperature. The temperature sensor can be positioned for avoiding interference with sensed magnetic flux. The controller can adjust the determined torque using the temperature measurements to compensate for changes in magnetic properties of the target due to variation in target temperature. In this manner, the accuracy of the torque measurements can be increased.
    Type: Application
    Filed: July 12, 2017
    Publication date: January 17, 2019
    Inventors: Dan Tho Lu, Pekka Tapani Sipila
  • Publication number: 20190003817
    Abstract: Integrated penetrator and proximity sensor probe assemblies are provided for monitoring a position of a rotating target within a subsea rotating device such as subsea motors and pumps. The integrated penetrator and proximity sensor probe assemblies are configured to communicate information related to the position of the rotating target through a wall of the device housing, and can be inserted through an opening in the wall of the device housing and mounted to the wall of the device to position a proximity sensor tip assembly adjacent the rotating target. The proximity sensor probe assemblies are pressure-compensated and configured to withstand subsea pressures and conditions.
    Type: Application
    Filed: June 20, 2018
    Publication date: January 3, 2019
    Applicant: General Electric Company
    Inventors: Lam Arthur Campbell, Dan Tho Lu, Svein Arild Haugen, Jens Abrahamsen
  • Publication number: 20180340846
    Abstract: Systems, methods, and devices for positioning, orienting, and/or aligning a stress sensor assembly are provided. In some embodiments, a sensor assembly can be received within a retaining element of a sensor mounting assembly. The sensor mounting assembly can include the retaining element, an adjustment mechanism, a first member, a second member, and a third member. The adjustment mechanism can allow the sensor assembly to be displaced linearly in a proximal and/or distal direction. The first and second members can be pivotally coupled to enable the sensor assembly to be rotated about a first axis, and the second and third members can be pivotally coupled to allow the sensor assembly to be rotated about a second axis.
    Type: Application
    Filed: May 26, 2017
    Publication date: November 29, 2018
    Inventors: Martin Bucher, David Folkner, Dan Tho Lu, Lysle Turnbeaugh, Brian F. Howard
  • Publication number: 20180335324
    Abstract: A pressure compensated sensing system and methods for using the same are provided. The system can include a housing, a seal, an incompressible fluid, and sensing elements. The seal can be positioned within a housing cavity and divide the cavity into two portions. A first cavity portion can be sealed from the fluid environment by the seal and contain the sensing elements and the incompressible fluid. A second cavity portion can be in fluid communication with the fluid environment. The fluid environment can apply an external pressure to the seal that is opposed by an internal pressure of the sealed cavity applied to the seal by the incompressible fluid. When the internal pressure and the external pressure are different, the seal can move in a manner that changes the volume of the sealed cavity by an amount sufficient to equalize the internal pressure with the external pressure.
    Type: Application
    Filed: May 17, 2017
    Publication date: November 22, 2018
    Inventors: Dan Tho Lu, Lam Arthur Campbell, David O'Connor, Bryan Shadel
  • Publication number: 20180335353
    Abstract: Systems, devices, and methods for determining stress in a conductive target are provided. The systems, devices, and methods facilitate detecting stress in the target using a sensor assembly. Raw stress signals, which can correspond to stress in the target, can be generated by detecting a first magnetic flux that travels through the target. The raw stress signals can be sensitive to a gap between the sensor assembly and the target. A proximity sensor element can be used to determine the size of the gap by generating a magnetic field which can couple with the target. If the size of the gap changes, the coupling can change. By determining an impedance of the proximity sensor element, a corresponding gap signal can be generated. The gap signal can be used to correct the raw stress signals, thereby creating corrected stress signals, which can correspond to values of stress within the target.
    Type: Application
    Filed: May 17, 2017
    Publication date: November 22, 2018
    Inventors: Dan Tho Lu, Pekka Tapani Sipila, Lam Arthur Campbell, Brian F. Howard
  • Publication number: 20180335352
    Abstract: Systems, devices, and methods for determining stress in a target are provided. The systems, devices, and methods facilitate detecting stress in the target using a sensor assembly. Using a sensor, taw stress signals, which can correspond to stress in the target, can be generated by detecting a magnetic flux that travels through the target. The raw stress signals can be sensitive to a gap between the sensor and the target. A proximity sensor element can be used to determine the size of the gap by generating an electric field between itself and the target. If the size of the gap changes, the strength of the electric field can change. Using a voltage of the proximity sensor element, a corresponding gap signal can be generated. The gap signal can be used to correct the raw stress signals, thereby creating corrected stress signals, which can correspond to stress values within the target.
    Type: Application
    Filed: May 17, 2017
    Publication date: November 22, 2018
    Inventor: Dan Tho Lu
  • Publication number: 20180335323
    Abstract: A pressure compensated sensing system and methods for using the same are provided. The system can include a housing, a seal, an incompressible fluid, and sensing elements. The seal can be positioned within a housing cavity and divide the cavity into two portions. A first cavity portion can be sealed from the fluid environment by the seal and contain the sensing elements and the incompressible fluid. A second cavity portion can be in fluid communication with the fluid environment. The fluid environment can apply an external pressure to the seal that is opposed by an internal pressure of the sealed cavity applied to the seal by the incompressible fluid. When the internal pressure and the external pressure are different, the seal can move in a manner that changes the volume of the sealed cavity by an amount sufficient to equalize the internal pressure with the external pressure.
    Type: Application
    Filed: May 17, 2017
    Publication date: November 22, 2018
    Inventor: Dan Tho Lu
  • Patent number: 10113921
    Abstract: Systems and methods are presented for cancelling noise from sensed magnetostriction-based strain measurements. A drive signal corresponds to a drive coil, and a sensed signal corresponds to a sensed coil. The drive signal is used to at least partially eliminate noise similar to the drive signal from the sensed signal to generate an output signal.
    Type: Grant
    Filed: October 3, 2016
    Date of Patent: October 30, 2018
    Assignee: GENERAL ELECTRIC COMPANY
    Inventors: Dan Tho Lu, Pekka Tapani Sipilä, Lysle Rollan Turnbeaugh
  • Patent number: 10094720
    Abstract: A system includes a magnetostrictive sensor. The magnetostrictive sensor includes a driving coil configured to receive a first driving current and to emit a first magnetic flux portion through a target and a second magnetic flux portion. The magnetostrictive sensor also includes a first sensing coil configured to receive the first magnetic flux portion and to transmit a signal based at least in part on the received first magnetic flux portion. The received first magnetic flux portion is based at least in part on a force on the target. The magnetostrictive sensor includes a magnetic shield disposed between the driving coil and the first sensing coil. The magnetic shield is configured to reduce the second magnetic flux portion received by the first sensing coil. The magnetic shield includes a composite with a conductive material and an insulating material, a metamaterial, or a mesh structure, or any combination thereof.
    Type: Grant
    Filed: August 29, 2016
    Date of Patent: October 9, 2018
    Assignee: General Electric Company
    Inventors: Pekka Tapani Sipila, Lam Arthur Campbell, Dan Tho Lu
  • Patent number: 10090093
    Abstract: A system includes a sensor configured to detect an electrical leakage current associated with an operation of an industrial machine. The sensor includes a core and a first winding encircling a first portion of the core. The first winding includes a first number of turns. The first winding is configured to obtain a set of electrical current measurements associated with the operation of the industrial machine. The sensor includes a second winding encircling a second portion of the core. The second winding includes a second number of turns. The second winding is configured to obtain the set of electrical current measurements associated with the operation of the industrial machine. The first winding and the second winding are each configured to generate respective outputs based on the set of electrical current measurements. The respective outputs are configured to be used to reduce the occurrence of a distortion of the set of electrical current measurements based on a temperature of the core.
    Type: Grant
    Filed: December 26, 2017
    Date of Patent: October 2, 2018
    Assignee: GENERAL ELECTRIC COMPANY
    Inventor: Dan Tho Lu
  • Publication number: 20180258786
    Abstract: A sensor assembly is described herein. The sensor assembly includes a housing that includes an inner surface that defines a cavity within the housing, and a proximity sensor positioned within the cavity. The proximity sensor includes a first connector, a second connector, and a substantially planar sensing coil that extends between the first connector and the second connector. The sensing coil extends outwardly from the first connector such that the second connector is radially outwardly from the first connector.
    Type: Application
    Filed: April 2, 2018
    Publication date: September 13, 2018
    Applicant: General Electric Company
    Inventors: Dan Tho Lu, Lam Arthur Campbell
  • Publication number: 20180217011
    Abstract: A stress sensing system for measuring stress in a conductive target material includes at least one sensor positioned proximate to the conductive target material. The sensor is configured to measure stress in the conductive target material and to transmit a signal indicative of the measured stress to a controller. The controller is coupled in communication with the sensor. The controller is configured to receive the signal from the sensor, determine a runout portion of the signal corresponding to the runout of the conductive target material, determine a runout pattern waveform from the runout portion, and subtract the runout pattern waveform from the signal.
    Type: Application
    Filed: January 27, 2017
    Publication date: August 2, 2018
    Inventors: Brian Howard, Dan Tho Lu, Lysle Turnbeaugh, David Erik Folkner
  • Patent number: 10024645
    Abstract: Sensor assemblies, electrical penetrator assemblies and associated methods are provided for monitoring operational characteristics of subsea rotating devices such as subsea motors and pumps. Pressure-compensated proximity sensors configured to withstand subsea pressures are disposed adjacent a subsea rotating shaft for directly monitoring a position of the rotating shaft during dynamic operation thereof. A sensor tip assembly includes a sensor cap and a sensing element therein configured to produce a signal indicative of a distance between the sensor cap and the rotating shaft. A substantially incompressible fluid is disposed within a fluid reservoir within a sensor housing, and fluidly communicates with the sensor cap such that at least a portion of an internal pressure within the sensor housing is applied to interior portions of the sensor cap. The sensor housing is configured such that the internal pressure increases in response to an increase in an external pressure of the sensor housing.
    Type: Grant
    Filed: April 28, 2017
    Date of Patent: July 17, 2018
    Inventors: Lam Arthur Campbell, Dan Tho Lu, Svein Arild Haugen, Jens Abrahamsen
  • Patent number: 10024742
    Abstract: A system includes a magnetostrictive sensor having a sensor head including a driving pole. The driving pole includes a driving coil that may receive a driving current and may emit a magnetic flux portion through a rotary structure. The sensor head also includes a sensing pole including a sensing coil that may receive the magnetic flux portion and may transmit a signal based at least in part on the received magnetic flux portion. The received magnetic flux portion is based at least in part on a force on the rotary structure. The sensor head also includes a temperature sensor disposed on the sensor head. The temperature sensor may measure a temperature of the rotary structure.
    Type: Grant
    Filed: April 10, 2017
    Date of Patent: July 17, 2018
    Assignee: General Electric Company
    Inventors: Dan Tho Lu, Pekka Tapani Sipila, Clifford James Uber