Patents by Inventor Yun-Ching Ma

Yun-Ching Ma 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: 20030067054
    Abstract: The present invention discloses a surface mountable device comprising a current-sensitive element and two electrodes. The current-sensitive element is composed of a PTC conductive composite, comprising at least one polymer and a conductive filler. The feature of the present invention is that the current-sensitive element is a three-dimensional bent structure so that the shape, length and height of the device can be varied according to the space of the circuit board and the resistance of the surface mountable device. Therefore, the mountable surface of the circuit board can be used more efficiently. Moreover, the area of the current-sensitive element of the present invention is larger than that of the conventional surface mountable device. Consequently, the normal resistance of the surface mountable device of the present invention is smaller than that of the conventional surface mountable device and the voltage endurance of the surface mountable device of the present invention is increased.
    Type: Application
    Filed: October 7, 2002
    Publication date: April 10, 2003
    Inventors: Edward Fu-Hua Chu, David Shau-Chew Wang, Yun-Ching Ma
  • Publication number: 20030067729
    Abstract: The present invention discloses an over-current protection apparatus, comprising a current-sensitive element, a first electrode and a second electrode. The over-current protection apparatus of the present invention is a three-dimensional multi-layer structure, and can be formed by heating, pressing, etching, cutting and multi-stage deformation to prevent it from breakage during the bending process. Therefore, the over-current protection apparatus with at least one bend is formed.
    Type: Application
    Filed: October 7, 2002
    Publication date: April 10, 2003
    Inventors: Edward Fu-Hua Chu, David Shau-Chew Wang, Yun-Ching Ma
  • Patent number: 6512446
    Abstract: The present invention discloses an over-current protection apparatus, which comprises a current-sensitive element and at least two electrodes. The current-sensitive element is composed of a positive temperature coefficient (PTC) conductive composition, which includes at least one polymer, a conductive filler and a non-conductive filler. The melting point of the polymer is greater then 110° C., and the vicat softening point of the polymer is smaller than 110° C. for improving the conductivity and thermal stabilization of the over-current protection apparatus.
    Type: Grant
    Filed: November 28, 2001
    Date of Patent: January 28, 2003
    Assignee: Polytronics Technology Corporation
    Inventors: David Shau-Chew Wang, Yun-Ching Ma, Chiung-Huei Shieh
  • Patent number: 6487084
    Abstract: A PCB comprising a substrate, at least one circuit layer and at least one insulating layer, characterized in that the PCB further comprises at least one embedded functional material such as a PTC, and NTC and ZTC material. If the PTC material is applied in the present invention, a normal resistance of the present invention will be substantially smaller than that of the conventional PTC protection apparatus since the area of the PTC material of the present invention is larger than that of the conventional PTC protection apparatus. Moreover, through an electrically conductive hole, an upper electrode and a lower electrode respectively lying on top and bottom surfaces of the functional material are respectively connected with an apparatus mounted on a surface of the PCB to form a conductive circuit. Thus, at least one over-current protection apparatus which is usually mounted on the surface of the PCB is eliminated, and the surface utilization rate of the PCB is improved.
    Type: Grant
    Filed: February 5, 2002
    Date of Patent: November 26, 2002
    Assignee: Polytronics Technology Corporation
    Inventors: Edward Fu-Hua Chu, Yun-Ching Ma, David Shau-Chew Wang
  • Publication number: 20020170747
    Abstract: The present invention discloses a PCB comprising a substrate, at least one circuit layer and at least one insulating layer, characterized in that the PCB further comprises at least one embedded functional material such as a PTC, and NTC and ZTC material. If the PTC material is applied in the present invention, a normal resistance of the present invention will be substantially smaller than that of the conventional PTC protection apparatus since the area of the PTC material of the present invention is larger than that of the conventional PTC protection apparatus. Moreover, through an electrically conductive hole, an upper electrode and a lower electrode respectively lying on top and bottom surfaces of the functional material are respectively connected with an apparatus mounted on a surface of the PCB to form a conductive circuit. Thus, at least one over-current protection apparatus which is usually mounted on the surface of the PCB is eliminated, and the surface utilization rate of the PCB is improved.
    Type: Application
    Filed: February 5, 2002
    Publication date: November 21, 2002
    Inventors: Edward Fu-Hua Chu, Yun-Ching Ma, David Shau-Chew Wang
  • Patent number: 6479575
    Abstract: Conductive polymer blend composites exhibiting PTC (positive temperature coefficient of resistance) behavior, comprising at least two types of polymers and preferably at least two types of conductive particulate materials (e.g., carbon blacks), and electrical devices containing such composites. The two polymers are selected to have different melt flow index values, while the two particulate materials are selected to have different average particle sizes and DBP values.
    Type: Grant
    Filed: April 19, 1999
    Date of Patent: November 12, 2002
    Assignee: Polytronics Technology Corporation
    Inventors: Fu-Hua Chu, Yun-Ching Ma
  • Publication number: 20020135985
    Abstract: The present invention relates to an over-current protecting apparatus, which comprises at least one PTC over-current protecting component and a body. The PTC over-current protecting component has a PTC material, electrodes covering the PTC material, and metal terminations electrically connected to the electrodes. The body has an insulating layer and a first conductive and second conductive regions covering the insulating layer. An end of the first conductive region and second conductive region are electrically connected to the metal terminations, and another ends of the first conductive and second conductive regions are mounted to a PCB. The metal material occupies over 20% area of the sidewall of the first conductive and second conductive regions for increasing solderability. Besides, the top of the PTC over-current protecting component can be adhered to another body to form a symmetrical bodies.
    Type: Application
    Filed: March 19, 2002
    Publication date: September 26, 2002
    Inventors: Edward Fu-Hua Chu, David Shau-Chew Wang, Yun-Ching Ma
  • Publication number: 20020109576
    Abstract: The present invention discloses an over-current protection apparatus, which comprises a current-sensitive element and at least two electrodes. The current-sensitive element is composed of a positive temperature coefficient (PTC) conductive composition, which includes at least one polymer, a conductive filler and a non-conductive filler. The melting point of the polymer is greater then 110° C., and the vicat softening point of the polymer is smaller than 110° C. for improving the conductivity and thermal stabilization of the over-current protection apparatus.
    Type: Application
    Filed: November 28, 2001
    Publication date: August 15, 2002
    Applicant: Polytronics Technology Corporation
    Inventors: David Shau-Chew Wang, Yun-Ching Ma, Chiung-Huei Shieh
  • Patent number: 6377467
    Abstract: The present invention relates to a novel thermal-sensitive resistive apparatus, such as PTC and NTC, which allocates planar electrode films on the top and bottom surfaces of a prior art thermal-sensitive resistive apparatus, such as a PTC apparatus, to laminate with an outer electrode layer. A plurality of interconnection vias are electroplated with conductive material to connect to any plane. It is convenient to surface mount the apparatus of the present invention on a printed circuit board. The present invention can largely increase the dimensional stability of components and overcome the disadvantage that thermal diffusion of the prior are surface mounted resistive apparatus is affected easily by line width and environments.
    Type: Grant
    Filed: April 4, 2000
    Date of Patent: April 23, 2002
    Assignee: Polytronics Technology Corporation
    Inventors: Fu-Hua Chu, Yun-Ching Ma, David Shau-Chew Wang