Patents by Inventor Leong Chew Lim

Leong Chew Lim 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: 11716908
    Abstract: Cost effective connectors of high bending stiffness for making high-performance piezoelectric actuators and derivative devices are disclosed. In one embodiment, the connector has circumferentially alternating recesses of circular cross-section which can be cost-effectively machined out with conventional machining techniques. The circular recesses can be adopted to house circular or non-circular cross-sectioned piezoelectric active elements to make cost effective 2-level (2×) piezoelectric displacement actuators. In another embodiment, the non-circular cross-sectioned recesses in the connector include suitable wall openings to enable said recesses to be machined out cost effectively via conventional machining techniques, or via reduced use of non-conventional machining techniques. Additional stiffening mechanisms can be added to minimize the bending displacement of the base of recesses when desired.
    Type: Grant
    Filed: June 12, 2017
    Date of Patent: August 1, 2023
    Assignee: MICROFINE MATERIALS TECHNOLOGIES PTE LTD
    Inventors: Leong Chew Lim, Yu Huang, Yuexue Xia, Dian-Hua Lin
  • Publication number: 20200176665
    Abstract: Cost effective connectors of high bending stiffness for making high-performance piezoelectric actuators and derivative devices are disclosed. In one embodiment, the connector has circumferentially alternating recesses of circular cross-section which can be cost-effectively machined out with conventional machining techniques. The circular recesses can be adopted to house circular or non-circular cross-sectioned piezoelectric active elements to make cost effective 2-level (2×) piezoelectric displacement actuators. In another embodiment, the non-circular cross-sectioned recesses in the connector include suitable wall openings to enable said recesses to be machined out cost effectively via conventional machining techniques, or via reduced use of non-conventional machining techniques. Additional stiffening mechanisms can be added to minimize the bending displacement of the base of recesses when desired.
    Type: Application
    Filed: June 12, 2017
    Publication date: June 4, 2020
    Inventors: Leong Chew LIM, Yu HUANG, Yuexue XIA, Dian-Hua LIN
  • Publication number: 20200128333
    Abstract: The invention provides a Diagonal Resonance (DR) mode for sound and ultrasound generation and reception. This new driving mode is made possible due to the anisotropic sound velocity in piezoelectric single crystals. This gives rise to a crossed slab active material, which contains the crossed-diagonals of the substantially rectangular shaped active material, exhibiting comparable resonance frequency. Due to reasonably large Piosson's ratios of lead-based relaxor single crystal, the resonance vibration of the active material in crossed face or body diagonal directions induces sufficiently large vibration amplitudes for sound and ultrasound generation via any free surface which could be normal or at an angle to the resonating diagonal directions. Said DR mode typically has lower resonance frequency than conventional longitudinal and transverse width modes but high TVR and can be combined or coupled with said two driving modes to make broadband to extra-broadband sonic and ultrasonic transducers.
    Type: Application
    Filed: June 19, 2017
    Publication date: April 23, 2020
    Inventors: Shuangjie ZHANG, Leong Chew LIM, Dianhua LIN
  • Publication number: 20190103821
    Abstract: Disclose displacement connectors of high bending stiffness, high-performance piezoelectric actuators and derivative devices made of such. The connector has circumferentially alternating recess housings which, when fitted with the intended piezoelectric active elements makes displacement actuators, approximately double (2×), triple (3×) or quadruple (4×) the displacement of individual active elements without adversely jeopardizing their regenerative forces. The connector may take any overall cross-section and length to suit intended applications. Connector recesses can be configured to house piezoelectric elements of a wide variety of cross-sections and dimensions, including longitudinal mode stacks, transverse mode bars and/or tubes, single crystal blocks of suitable cut and dimensions and their bonded assemblages.
    Type: Application
    Filed: April 7, 2016
    Publication date: April 4, 2019
    Inventors: Leong Chew LIM, Yu HUANG, Yuexue XIA, Dian-Hui LIN
  • Patent number: 6592805
    Abstract: A method for producing electroceramic materials of high sintered density from hydroxide and/or oxalate precursors is disclosed. In this method the precursor(s) are compacted to form a preform, thermally treated, recompacted and then sintered to form finished products.
    Type: Grant
    Filed: June 21, 2001
    Date of Patent: July 15, 2003
    Assignee: National University of Singapore
    Inventors: John Wang, Junmin Xue, Leong Ming Gan, Ser Choon Ng, Leong Chew Lim
  • Patent number: 5509980
    Abstract: The present invention is directed to a pre-weld overageing heat treatment for nickel-based superalloys, where the alloy is heated to solutionization temperature for a time sufficient to dissolve the gamma prime phase of the alloy microstructure, then slowly cooled with periods of intermittent heating, so that the gamma prime phase reprecipitates as coarse equiaxed particles, and the presence of fine sized gamma prime phase particles is substantially avoided. The present invention is also directed to a welding method wherein said pre-weld overageing treatment is used.
    Type: Grant
    Filed: August 17, 1994
    Date of Patent: April 23, 1996
    Assignee: National University of Singapore
    Inventor: Leong-Chew Lim