Patents by Inventor Abraham Johannes Oberholster

Abraham Johannes Oberholster 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: 11609114
    Abstract: A method (400) of determining blade tip deflection characteristics is applied to moving rotor blades (R1, R2) in a turbomachine (10) comprising a housing and rotor including a shaft with the rotor blades attached thereto and at least one proximity probe (202). The method (400) includes measuring ((402) a proximity signal caused by a presence of a proximate tip of a moving rotor blade (R1) and calculating (404) by a control module (212) a shaft Instantaneous Angular Position (IAP) as a function of time, and performing (410) an order tracking process which includes expressing (412) the measured proximity signal in the angular domain and resampling (414) the expressed proximity signal to render it equidistant in the angular domain.
    Type: Grant
    Filed: June 27, 2017
    Date of Patent: March 21, 2023
    Assignee: University of Pretoria
    Inventors: David Hercules Diamond, Philippus Stephanus Heyns, Abraham Johannes Oberholster
  • Patent number: 11333033
    Abstract: A method (400) of measuring rotor blade tip deflections of turbomachine rotor blades (R1, R2) during operation using Blade Tip Timing (BTT) includes measuring (402), by a proximity sensor (202), a proximity signal caused by a moving rotor blade (R1, R2) and determining (412), by a control module (212), a Time-of-Arrival (ToA). The method (400) includes measuring a time that the shaft starts to rotate a measurable angular distance and a time the shaft has completed its rotation of the measurable distance and storing (406) timing data indicative of a plurality of ToA measurements of the rotor blade (R1, R2) and the zero crossing times.
    Type: Grant
    Filed: June 27, 2017
    Date of Patent: May 17, 2022
    Assignee: University of Pretoria
    Inventors: David Hercules Diamond, Philippus Stephanus Heyns, Abraham Johannes Oberholster
  • Patent number: 10895496
    Abstract: A method of estimating vibration characteristics of moving rotor blades in a turbomachine comprising a housing and rotor including a shaft with the rotor blades attached thereto includes measuring, by at least one proximity sensor, a Time-of-Arrival (ToA) of a proximate tip of a moving rotor blade. The method includes manipulating, by a control module, timing data to determine a corresponding blade tip deflection at each measured ToA, expressing blade tip vibration behaviour as a Bayesian statistical model consisting of intermediate model parameters, wherein model coefficients in the statistical model are probabilistic quantities as opposed to conventional, deterministic quantities, and expressing, by the control module, the determined blade tip deflections as observed values in the statistical model.
    Type: Grant
    Filed: April 25, 2017
    Date of Patent: January 19, 2021
    Assignee: University of Pretoria
    Inventors: David Hercules Diamond, Philippus Stephanus Heyns, Abraham Johannes Oberholster
  • Publication number: 20200249074
    Abstract: A method of estimating vibration characteristics of moving rotor blades in a turbomachine comprising a housing and rotor including a shaft with the rotor blades attached thereto includes measuring, by at least one proximity sensor, a Time-of-Arrival (ToA) of a proximate tip of a moving rotor blade. The method includes manipulating, by a control module, timing data to determine a corresponding blade tip deflection at each measured ToA, expressing blade tip vibration behaviour as a Bayesian statistical model consisting of intermediate model parameters, wherein model coefficients in the statistical model are probabilistic quantities as opposed to conventional, deterministic quantities, and expressing, by the control module, the determined blade tip deflections as observed values in the statistical model.
    Type: Application
    Filed: April 25, 2017
    Publication date: August 6, 2020
    Inventors: David Hercules Diamond, Philippus Stephanus Heyns, Abraham Johannes Oberholster
  • Publication number: 20190376406
    Abstract: A method (400) of measuring rotor blade tip deflections of turbomachine rotor blades (R1, R2) during operation using Blade Tip Timing (BTT) includes measuring (402), by a proximity sensor (202), a proximity signal caused by a moving rotor blade (R1, R2) and determining (412), by a control module (212), a Time-of-Arrival (ToA). The method (400) includes measuring a time that the shaft starts to rotate a measurable angular distance and a time the shaft has completed its rotation of the measurable distance and storing (406) timing data indicative of a plurality of ToA measurements of the rotor blade (R1, R2) and the zero crossing times.
    Type: Application
    Filed: June 27, 2017
    Publication date: December 12, 2019
    Applicant: University of Pretoria
    Inventors: David Hercules DIAMOND, Philippus Stephanus HEYNS, Abraham Johannes OBERHOLSTER
  • Publication number: 20190212188
    Abstract: A method (400) of determining blade tip deflection characteristics is applied to moving rotor blades (R1, R2) in a turbomachine (10) comprising a housing and rotor including a shaft with the rotor blades attached thereto and at least one proximity probe (202). The method (400) includes measuring ((402) a proximity signal caused by a presence of a proximate tip of a moving rotor blade (R1) and calculating (404) by a control module (212) a shaft Instantaneous Angular Position (IAP) as a function of time, and performing (410) an order tracking process which includes expressing (412) the measured proximity signal in the angular domain and resampling (414) the expressed proximity signal to render it equidistant in the angular domain.
    Type: Application
    Filed: June 27, 2017
    Publication date: July 11, 2019
    Applicant: University of Pretoria
    Inventors: David Hercules Diamond, Philippus Stephanus Heyns, Abraham Johannes Oberholster