Patents by Inventor Daniel H. Chang

Daniel H. Chang 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: 7271369
    Abstract: An improved PTC device and method of manufacturing is disclosed. In one embodiment, the device and method incorporates an improved metal-ceramic composite PTC material manufactured by: (a) heating a ceramic material to a sufficiently high temperature to induce the ceramic material's PTC properties; (b) grinding the ceramic PTC material into a powder; (c) mixing the ceramic PTC material powder with a metal material powder so as to produce a metal-ceramic composite material powder; and (d) sintering the composite material powder at a temperature between 600° and 950° C. In alternative embodiments, an improved multi-layer structure and method of manufacturing such a structure is disclosed. In various embodiments, a PTC device made in accordance with the improved multi-layer structure and method of manufacture may or may not incorporate the improved metal-ceramic composite PTC material disclosed herein, but may use conventional ceramic-based PTC materials.
    Type: Grant
    Filed: August 26, 2005
    Date of Patent: September 18, 2007
    Assignee: AEM, Inc.
    Inventors: Xiang-Ming Li, Xiaopeng Yang, Liwu Wang, Daniel H. Chang
  • Patent number: 7268661
    Abstract: A composite fuse element includes a network or matrix of conductive material that is in contact and interspersed with arc suppressing materials at a particle level. In such a matrix, the conductive (e.g., metal) network and the arc suppressing material particles provides a large contact surface area between these materials. When the conductive network melts or vaporizes, the resulting conductive vapors are adsorbed into the arc suppressing particles in a short time due to the large contact area between conductive and arc suppressing materials and the short diffusion distance that the conductive vapors are required to travel before they are absorbed by the arc suppressing material.
    Type: Grant
    Filed: September 27, 2004
    Date of Patent: September 11, 2007
    Assignee: AEM, Inc.
    Inventors: Xiang-Ming Li, Liwu Wang, Jeffrey D. Montgomery, Daniel H. Chang
  • Patent number: 6847751
    Abstract: A structure for effecting a transition from a passive waveguide to an active waveguide or from an active waveguide to a passive waveguide of the present invention. The inventive device comprises a first cladding; a first core disposed within the first cladding; and a ground plane disposed over the first cladding and the core. A second cladding is disposed on the ground plane. A second core is disposed on the second cladding. A third cladding is disposed on the second cladding and the second core and an electrode is disposed on top of the third cladding. The inventive structure enables the construction of a novel an advantageous switch comprising an input port; an output port; and plural waveguides disposed between the input port and the output port. Each waveguide includes a first cladding; a first core disposed within the first cladding; and a ground plane disposed over the first cladding and the core. A second cladding is disposed on the ground plane. A second core is disposed on the second cladding.
    Type: Grant
    Filed: August 11, 2003
    Date of Patent: January 25, 2005
    Assignee: Pacific Wave Industries, Inc.
    Inventors: Daniel H. Chang, Talal Azfar, Harold R. Fetterman, Joseph Michael
  • Patent number: 6844278
    Abstract: A dense lead-free glass ceramic that has low dielectric constant and low dielectric loss for producing high-frequency ceramic devices, such as inductors and low temperature co-fired ceramics (LTCC), is disclosed. The glass ceramic consists of 15-35% by weight of lead-free borosilicate glasses with low softening point, 15-35% by weight of lead-free borosilicate glasses with high softening point, 20-80% by weight of combination of amorphous and crystalline SiO2-filler (preferably 5-30% by weight of amorphous SiO2, 10-50% by weight of crystalline SiO2) and 0.1-10% by weight of at least one oxide of Al2O3, BaO, Sb2O3, V2O5, CoO, MgO, B2O3, Nb2O5, SrO and ZnO. The glass ceramic can be densified up to 99% of its theoretical density after firing and is co-firable with conductive metals between 800-900° C. The dense glass ceramic has dielectric constant of 4.2-4.6 and loss tangent (tan ?)<0.0025 at 20 MHz and good thermal/mechanical strength for application in high frequency electronic devices.
    Type: Grant
    Filed: September 18, 2002
    Date of Patent: January 18, 2005
    Assignee: AEM, Inc.
    Inventors: Liwu Wang, Xiang-Ming Li, Albert Tian, Daniel H. Chang, Zhong Zheng
  • Publication number: 20040071402
    Abstract: A structure for effecting a transition from a passive waveguide to an active waveguide or from an active waveguide to a passive waveguide of the present invention. The inventive device comprises a first cladding; a first core disposed within the first cladding; and a ground plane disposed over the first cladding and the core. A second cladding is disposed on the ground plane. A second core is disposed on the second cladding. A third cladding is disposed on the second cladding and the second core and an electrode is disposed on top of the third cladding. The inventive structure enables the construction of a novel an advantageous switch comprising an input port; an output port; and plural waveguides disposed between the input port and the output port. Each waveguide includes a first cladding; a first core disposed within the first cladding; and a ground plane disposed over the first cladding and the core. A second cladding is disposed on the ground plane. A second core is disposed on the second cladding.
    Type: Application
    Filed: August 11, 2003
    Publication date: April 15, 2004
    Inventors: Daniel H. Chang, Talal Azfar, Harold R. Fetterman, Joseph Michael
  • Publication number: 20040047544
    Abstract: A structure for effecting a transition from a passive waveguide to an active waveguide or from an active waveguide to a passive waveguide of the present invention. The inventive device comprises a first cladding; a first core disposed within the first cladding; and a ground plane disposed over the first cladding and the core. A second cladding is disposed on the ground plane. A second core is disposed on the second cladding. A third cladding is disposed on the second cladding and the second core and an electrode is disposed on top of the third cladding. The inventive structure enables the construction of a novel an advantageous switch comprising an input port; an output port; and plural waveguides disposed between the input port and the output port. Each waveguide includes a first cladding; a first core disposed within the first cladding; and a ground plane disposed over the first cladding and the core. A second cladding is disposed on the ground plane. A second core is disposed on the second cladding.
    Type: Application
    Filed: August 11, 2003
    Publication date: March 11, 2004
    Inventors: Daniel H. Chang, Talal Azfar, Harold R. Fetterman, Joseph Michael
  • Patent number: 6643419
    Abstract: A structure for effecting a transition from a passive waveguide to an active waveguide or from an active waveguide to a passive waveguide of the present invention. The inventive device comprises a first cladding; a first core disposed within the first cladding; and a ground plane disposed over the first cladding and the core. A second cladding is disposed on the ground plane. A second core is disposed on the second cladding. A third cladding is disposed on the second cladding and the second core and an electrode is disposed on top of the third cladding. The inventive structure enables the construction of a novel an advantageous switch comprising an input port; an output port; and plural waveguides disposed between the input port and the output port. Each waveguide includes a first cladding; a first core disposed within the first cladding; and a ground plane disposed over the first cladding and the core. A second cladding is disposed on the ground plane. A second core is disposed on the second cladding.
    Type: Grant
    Filed: December 5, 2001
    Date of Patent: November 4, 2003
    Assignee: Pacific Wave Industries, Inc.
    Inventors: Daniel H. Chang, Talal Azfar, Harold R. Fetterman, Joseph Michael
  • Patent number: 6602766
    Abstract: A multilayered electronic component with or without inter-layer connections created by a process using radiation curing such as ultraviolet/electron beam curing techniques. UV light or electron beam curable binders are mixed with ceramic powders and metals powders to form a ceramic slurry and electrode ink, there is little or no solvent in the metal ink and ceramic slurry. Instead of drying, a UV or electron beam is used for curing the binders. These binders could contain UV/electron beam curable monomers or oligomers, photo initiators, and other additives to provide the desired chemical and physical properties in the forming process.
    Type: Grant
    Filed: November 27, 2001
    Date of Patent: August 5, 2003
    Assignee: AEM, Inc.
    Inventors: Daniel H. Chang, Xiang-Ming Li
  • Publication number: 20030103710
    Abstract: A structure for effecting a transition from a passive waveguide to an active waveguide or from an active waveguide to a passive waveguide of the present invention. The inventive device comprises a first cladding; a first core disposed within the first cladding; and a ground plane disposed over the first cladding and the core. A second cladding is disposed on the ground plane. A second core is disposed on the second cladding. A third cladding is disposed on the second cladding and the second core and an electrode is disposed on top of the third cladding. The inventive structure enables the construction of a novel an advantageous switch comprising an input port; an output port; and plural waveguides disposed between the input port and the output port. Each waveguide includes a first cladding; a first core disposed within the first cladding; and a ground plane disposed over the first cladding and the core. A second cladding is disposed on the ground plane. A second core is disposed on the second cladding.
    Type: Application
    Filed: December 5, 2001
    Publication date: June 5, 2003
    Inventors: Daniel H. Chang, Talal Azfar, Harold R. Fetterman, Joseph Michael
  • Publication number: 20030096692
    Abstract: A dense lead-free glass ceramic that has low dielectric constant and low dielectric loss for producing high-frequency ceramic devices, such as inductors and low temperature co-fired ceramics (LTCC), is disclosed. The glass ceramic consists of 15-35% by weight of lead-free borosilicate glasses with low softening point, 15-35% by weight of lead-free borosilicate glasses with high softening point, 20-80% by weight of combination of amorphous and crystalline SiO2-filler (preferably 5-30% by weight of amorphous SiO2, 10-50% by weight of crystalline SiO2) and 0.1-10% by weight of at least one oxide of Al2O3, BaO, Sb2O3, V2O5, CoO, MgO, B2O3, Nb2O5, SrO and ZnO. The glass ceramic can be densified up to 99% of its theoretical density after firing and is co-firable with conductive metals between 800-900° C. The dense glass ceramic has dielectric constant of 4.2-4.6 and loss tangent (tan &dgr;)<0.0025 at 20 MHz and good thermal/mechanical strength for application in high frequency electronic devices.
    Type: Application
    Filed: September 18, 2002
    Publication date: May 22, 2003
    Applicant: AEM, Inc.
    Inventors: Liwu Wang, Xiang-Ming Li, Albert Tian, Daniel H. Chang, Zhong Zheng
  • Publication number: 20030024111
    Abstract: A multilayered electronic component with inter-layer connections is created by a process using dot penetration techniques. Electrodes are formed on a substrate. One or more conductive structures are formed on the electrodes to provide for interlayer electrical connections. A non-conductive (e.g., ceramic) sheet is laminated on top of the conductive dots under elevated pressure and temperature to cause the dot to penetrate through the ceramic sheet. A second electrode is printed on top of the penetrated conductive structure to complete the interlayer electrical connection without having to punch holes to form vias in the ceramic sheet.
    Type: Application
    Filed: August 2, 2002
    Publication date: February 6, 2003
    Applicant: AEM, Inc.
    Inventors: Daniel H. Chang, Xiang-Ming Li, Liwu Wang
  • Publication number: 20020072205
    Abstract: A multilayered electronic component with or without inter-layer connections created by a process using radiation curing such as ultraviolet/electron beam curing techniques. UV light or electron beam curable binders are mixed with ceramic powders and metals powders to form a ceramic slurry and electrode ink, there is little or no solvent in the metal ink and ceramic slurry. Instead of drying, a UV or electron beam is used for curing the binders. These binders could contain UV/electron beam curable monomers or oligomers, photo initiators, and other additives to provide the desired chemical and physical properties in the forming process.
    Type: Application
    Filed: November 27, 2001
    Publication date: June 13, 2002
    Inventors: Daniel H. Chang, Xiang-Ming Li
  • Patent number: 6228230
    Abstract: An apparatus for electroplating small parts comprises an electroplating bath for holding an electrolyte and electroplating anodes. The apparatus includes a container having at least one screened parts compartment for holding the parts to be electroplated, and incorporates an electrically conductive screen as its base portion, on which the parts are settled. The conductive screen is adaptable to be connected to the negative pole of a power supply to function as the cathode. A pump circulates freshly ionized electrolyte into the parts compartment and directs a flow of the electrolyte to periodically tumble the parts in the parts compartment. Thereafter, the parts are shaken by a shaker to level the parts to maximize the surface and electrical contact between the parts and the screen when they are settled on the screen. In alternative embodiments of the invention, the container can be of perforated panel construction.
    Type: Grant
    Filed: April 19, 1999
    Date of Patent: May 8, 2001
    Assignee: AEM, Inc.
    Inventors: Xiang-Ming Li, Tom w. Lamayeau, Kenneth McMasters Wallace, Bruce W. Hess, William DeoGracias, Daniel H. Chang
  • Patent number: 6034589
    Abstract: A surface mount fuse includes a plurality of substrate/arc suppressive layers, a plurality of fusible elements positioned between the substrate/arc suppressive layers and terminations connected to the ends of the fusible elements, such that the fusible elements are electrically connected in parallel. The surface mount fuse has greater amperage and voltage ratings than similarly sized conventional surface mount fuses. Additionally, the surface mount fuse has increased interrupt breaking capacity and superior mechanical properties.
    Type: Grant
    Filed: December 17, 1998
    Date of Patent: March 7, 2000
    Assignee: AEM, Inc.
    Inventors: Jeffrey D. Montgomery, Xiangming Li, Daniel H. Chang, Kenneth M. Wallace, Kenneth X. Kuang
  • Patent number: 5650199
    Abstract: A multilayered electronic component created by a wet process, wherein a ceramic base is imprinted with an electrode and an interlayer via is formed on top of it by introducing a via pattern printed in ink that is incompatible with a layer of wet ceramic slurry coating placed on top of the electrode and the via pattern. The incompatibility leads to a physical-chemical reaction that removes ceramic material away from the top of the via pattern by diffusing ceramic materials contained in a colloidal suspension forming a via-through hole. After the wet ceramic slurry is dried, it surrounds the via-through hole and the imprinted via pattern. Then a new electrode layer is imprinted on top of the dried ceramic coating. The new electrode layer completes an electrically conductive path formed from the bottom-most electrode layer, to the via pattern, and then terminating at the new electrode layer on top.
    Type: Grant
    Filed: November 22, 1995
    Date of Patent: July 22, 1997
    Assignee: AEM, Inc.
    Inventors: Daniel H. Chang, Arthur C. McAdams, Xiangming Li