公开(公告)号：JPH08191003A

公开(公告)日：1996-07-23

申请号：JP19547895

申请日：1995-07-31

Applicant: ABB RESEARCH LTD

Inventor： RUCHIKA ROITOTSURU ,  REOPORUTO RITSUTSUERU ,  RARUFU SHIYUTORIYUMUPURAA

IPC: H01B1/20 ,  H01C7/02

Abstract: PROBLEM TO BE SOLVED: To obtain a method for producing a PTC resistor exhibiting low resistivity and high current conductivity at a high temperature. SOLUTION: A polymer is admixed with a filler composed of a material having high electric conductivity and a resistor is made of the mixture. A substance having high glass transition point, melting point or crosslinking point, where PTC transition takes place only at 140 deg.C or above, is selected as the polymer. An oxidation resistant substance harder than carbon black or silver is selected as the filler. The filler is stocked in a low pressure or a nonoxidative atmosphere, especially in a protective gas atmosphere, and/or fused chemically before being mixed. Improvement in the properties of a PTC resistor thus produced can be achieved when the polymer is hardened or annealed in at least two temperature stages of the process for molding the resistor body part W.

公开(公告)号：JPH097802A

公开(公告)日：1997-01-10

申请号：JP13379396

申请日：1996-05-28

Applicant: ABB RESEARCH LTD

Inventor： GERUTO MAIDORUN ,  RARUFU SHIYUTORIYUMUPURAA

IPC: H01C7/02

Abstract: PROBLEM TO BE SOLVED: To rapidly suppress the shortcircuit current or overcurrent flowing in an electric circuit by specifying the main volume percent of a filler to be the percentage of particles with the mean diameter within a specific range. SOLUTION: Within the PTC resistor made of a compound material having high molecular mother material and a powdery filler of a conductive material buried in the mother material having electric resistor main body arranged between two contact terminals, the main volume percentage of the filler is the percentage of particles with less than 100μm and more than 5μm in the mean diameter. Since this PTC resistor extremely rapidly responds to shortcircuit or overcurrent, the current can be suppressed in the early time. Furthermore, this PTC resistor receives a relatively low energy thereby enabling the occurrence of overheated local region to be avoided without being affected by high thermal load or electric load.

公开(公告)号：JPH08237836A

公开(公告)日：1996-09-13

申请号：JP410996

申请日：1996-01-12

Applicant: ABB RESEARCH LTD

Inventor： RARUFU SHIYUTORIYUMUPURAA

IPC: H02G5/06 ,  H01B9/02

Abstract: PROBLEM TO BE SOLVED: To obtain a uniform electric field distribution by containing a dielectric substance, including a dielectric constant which increases nonlinearly as the temperature rises. SOLUTION: Electric parts which are insulated by a gas which is filled into a metal capsule are provided with a current conductor 2 for supplying a high voltage with a radius r1 which is arranged at the shaft of a tubular metal casing 1 with a radius of r2 . An insulation gas SF6 is filled into the metal casing 1 at several bar pressure. An equal voltage ranging from several kV to 1,000 MV is applied to the current conductor 2. A hollow cylindrical insulator 3 is formed at an area between the current conductor 2, which is retained by the metal casing 1. The insulator 3 is used as a polymer-filling agent with an epoxy resin base, where BaTiO3 with 10-60 capacity % having for example an average grain size of 2 μm is blended, thus easily providing a uniform electric field distribution.

公开(公告)号：JPH06215903A

公开(公告)日：1994-08-05

申请号：JP24531793

申请日：1993-09-30

Applicant: ABB RESEARCH LTD

Inventor： ANTON DEMARUMERUSU ,  FUERITSUKUSU GUROITAA ,  RARUFU SHIYUTORIYUMUPURAA

IPC: H01C7/02

Abstract: PURPOSE: To obtain an electrical resistance element with a short response time by providing a conductive surface or forming as a hollow body that is made of a conductive material or as a porous body. CONSTITUTION: A conductive particle is formed as a compound material body. The particle is formed on a support 7 that is made of a material that has a lower specific density than a conductive material and/or has a smaller specific heat amount by laminating a layer 6 that is made of the conductive material. The diameter of the particle is 1-200 μ and the thickness of the layer 6 that is made of a conductive material is 0.05-5 μm. Then, the particle has a lower specific density and a smaller specific heat amount than a resistance element where a particle that is made of a conductive material being formed truthfully is filled, thus increasing the conductivity of a low ohm state and reducing the response time for PFC move from a low ohm state to a high ohm state regardless of a simple and inexpensive structure.