Granular Or Powdered Element Patents (Class 338/223)
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Patent number: 8698592Abstract: Provided is a barium titanate-based semiconductor ceramic composition which contains no Pb, which can have an increased Curie temperature, which exhibits slight deterioration with time, and which has high reliability, containing a barium titanate-based semiconductor ceramic represented by the composition formula (Ba1-x-y-zSry(A1Bi)xA2z)TiO3, where A1 is an alkali metal element, A2 is a rare-earth element, 0.03?x?0.20, 0.02?y?0.20, and 0.0005?z?0.015, and x?0.10?y?(5/4)·x. In addition, 0.01 to 0.20 molar parts of Mn per 100 molar parts of Ti is preferably added thereto.Type: GrantFiled: March 23, 2011Date of Patent: April 15, 2014Assignee: Murata Manufacturing Co., Ltd.Inventor: Hayato Katsu
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Patent number: 8562859Abstract: A voltage nonlinear resistor is made of a sintered body that mainly includes zinc oxide grains, spinel grains including zinc and antimony as main ingredients, and a bismuth oxide phase, in which the bismuth oxide phase includes at least one of alkali metals selected from the group of potassium and sodium at a ratio in the range of 0.036 at % or higher and 0.176 at % or lower. The voltage nonlinear resistor has good voltage nonlinearity and loading service life characteristics, and can be used for a lightning arrester.Type: GrantFiled: November 17, 2008Date of Patent: October 22, 2013Assignee: Mitsubishi Electric CorporationInventors: Tomoaki Kato, Iwao Kawamata, Yoshio Takada
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Patent number: 8421583Abstract: There is provided a PTC device wherein its PTC element functions appropriately even when the PTC device is used in an environment in which solvent is present. The PTC device includes: (1) a polymer PTC component including a polymer PTC element and a first and a second metal electrodes disposed on both sides of the main surface thereof; (2) a lead connected to at least one of the metal electrodes of the polymer PTC component; and (3) a ceramic package having an open-ended space for accommodating the polymer PTC component, said open-ended space having at least one opening that defines the open-ended space. The lead closes said opening in order to isolate the polymer PTC component disposed in said open-ended space from the environment surrounding the ceramic package.Type: GrantFiled: June 5, 2009Date of Patent: April 16, 2013Assignee: Tyco Electronics Japan G.K.Inventor: Hiroyuki Koyama
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Patent number: 8362869Abstract: A thermistor based on a composition having the general formula (I): Re2-x-yCraMnbMcEyOz wherein Re is a rare earth metal or a mixture of two or more rare earth metals, M is a metal selected from the group consisting of nickel, cobalt, copper, magnesium and mixtures thereof, E is a metal selected from the group consisting of calcium, strontium, barium and mixtures thereof, x is the sum of a+b+c and is a number between 0.1 and 1, and the relative ratio of the molar fractions a, b and c is in an area bounded by points A, B, C and D in a ternary diagram, wherein point A is, if y<0.006, at (Cr=0.00, Mn=0.93+10?y, M=0.07?10?y), and, if y?0.006, at (Cr=0?00, Mn=0.99, M=0.01), point B is, if y<0.006, at (Cr=0.83, Mn=0.10+10?y, M=0.07?10?y), and, if y?0.006, at (Cr=0.83, Mn=0.16, M=0.01), point C is at (Cr=0.50, Mn=0.10, M=0.40) and point D is at (Cr=0.00, Mn=0.51, M=0.49), y is a number between 0 and 0.5?x, and z is a number between 2.5 and 3.5.Type: GrantFiled: December 19, 2008Date of Patent: January 29, 2013Assignee: Vishay Resistors Belgium BVBAInventors: Véronique Poulain, Sophie Schuurman, André Lannoo, Frans F. Westendorp
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Patent number: 8284013Abstract: A semiconductor ceramic includes a BamTiO3-based composition, as a main component, having a perovskite structure represented by general formula AmBO3. Part of Ba constituting an A site is replaced with at least an alkali metal element, Bi, and a rare-earth element, and the molar ratio m between the A site and a B site is 0.990?m?0.999 (preferably 0.990?m?0.995). Preferably, part of the Ba is replaced with Ca, and the content of the Ca when the total number of moles of the elements constituting the A site is 1 mole is 0.042 to 0.20 (preferably 0.125 to 0.175) on a molar basis. A PTC thermistor includes a component body formed of the semiconductor ceramic. Accordingly, there are provided satisfactory rise characteristics even if an alkali metal element is present.Type: GrantFiled: May 19, 2011Date of Patent: October 9, 2012Assignee: Murata Manufacturing Co., Ltd.Inventors: Masato Goto, Hayato Katsu, Naoaki Abe, Atsushi Kishimoto, Akinori Nakayama
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Film resistor with a constant temperature coefficient and production of a film resistor of this type
Patent number: 8198978Abstract: The invention relates to a film resistor (1) comprising a carbon-containing material (3) into which clusters (4) of conductive cluster material are introduced, wherein the conductive cluster material has a positive temperature coefficient. The clusters (4) are surrounded by a graphite casing and embedded in the carbon-containing material (3). Furthermore, the cluster material is present in a thermodynamically stable phase.Type: GrantFiled: April 6, 2009Date of Patent: June 12, 2012Assignees: Hochschule fur Technik und Wirtschaft des Sarlandes, Siegert Thinfilm Technology GmbHInventors: Günther Schultes, Dirk Göttel, Ralf Koppert, Olivia Freitag-Weber, Ulf Werner, Wolfgang Brode -
Patent number: 8151649Abstract: A physical quantity sensor device (10) having a structure in which a stress-sensitive body (1) of which the electric characteristics vary depending upon the application of stress and an insulator (2) having electric insulation are formed being closely adhered together, wherein the stress-sensitive body (1) comprises a thin glass film containing an electrically conductive element that is solidly dissolved therein as atoms, a method of manufacturing the physical quantity sensor device, a piezo-resistive film comprising a thin glass film containing ruthenium that is solidly dissolved therein as atoms, and a method of manufacturing the piezo-resistive film.Type: GrantFiled: May 28, 2010Date of Patent: April 10, 2012Assignee: Denso CorporationInventors: Masashi Totokawa, Masao Naito, Akihiro Takeichi
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Patent number: 8063730Abstract: An electrical device includes a thermistor and at least two electrodes electrically connected to the thermistor and to which a source of electrical power is applied to cause current to flow through the thermistor. The thermistor may be a composite and includes a polymer material; and a plurality of conductive carbon nanotubes distributed in the polymer material. The electrical device employed with the thermistor performs not only PTC property, but also NTC property. Moreover, the method for fabricating the electrical device is also simple and easy to carry out because of the simple process.Type: GrantFiled: March 12, 2009Date of Patent: November 22, 2011Assignees: Tsinghua University, Hon Hai Precision Industry Co., Ltd.Inventors: Lu-Zhuo Chen, Chang-Hong Liu, Shou-Shan Fan
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FILM RESISTOR WITH A CONSTANT TEMPERATURE COEFFICIENT AND PRODUCTION OF A FILM RESISTOR OF THIS TYPE
Publication number: 20110102127Abstract: The invention relates to a film resistor (1) comprising a carbon-containing material (3) into which clusters (4) of conductive cluster material are introduced, wherein the conductive cluster material has a positive temperature coefficient. The clusters (4) are surrounded by a graphite casing and embedded in the carbon-containing material (3). Furthermore, the cluster material is present in a thermodynamically stable phase.Type: ApplicationFiled: April 6, 2009Publication date: May 5, 2011Inventors: Günther Schultes, Dirk Göttel, Ralf Koppert, Olivia Freitag-Weber, Ulf Werner, Wolfgang Brode -
Patent number: 7764161Abstract: A barium titanate-based semiconductor ceramic composition and a PTC element that have a high Curie temperature and a low electrical resistivity at room temperature and that exhibit a desired rate of change in resistance are provided. The barium titanate-based semiconductor ceramic composition is a ceramic composition having a perovskite structure containing at least barium and titanium, wherein some of the barium is replaced with an alkali metal element, bismuth, and a rare earth element, and when the content of the titanium is assumed to be 100 parts by mole, a ratio of the content of the alkali metal element to the content of the bismuth plus the content of the rare earth element represented by parts by mole, is 1.00 or more and 1.06 or less. A PTC thermistor includes a ceramic body composed of the barium titanate-based semiconductor ceramic composition having the above feature and electrodes disposed on both side faces of the ceramic body.Type: GrantFiled: March 27, 2009Date of Patent: July 27, 2010Assignee: Murata Manufacturing Co., Ltd.Inventors: Hayato Katsu, Kenjirou Mihara, Hideaki Niimi
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Patent number: 7675401Abstract: A circuit board, for an electronic circuit having a passive circuit component, has a component region, a non-component region, and circuit wiring conductors on its surface. The component region includes a polymer composition comprising a mixture of polymer resin and filler material that, in combination with the circuit wiring conductors, forms the passive circuit component.Type: GrantFiled: June 9, 2005Date of Patent: March 9, 2010Assignee: The Hong Kong Polytechnic UniversityInventors: Ka Wai Eric Cheng, Chak Yin Tang
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Patent number: 7649436Abstract: A preferred varistor body has a structure of alternately laminated internal electrode layer and varistor layer made of a varistor material. The varistor layer has a composition containing Zn, Co, Pr, Li, and Zr. The analysis of varistor body in the depth direction from the surface thereof gives the Li content of 0.08 parts by mass or less to 100 parts by mass of the sum of Zn, Co, and Pr contents at a level of 2 ?m at the surface side above the reference depth where the Zr content becomes almost constant.Type: GrantFiled: March 27, 2007Date of Patent: January 19, 2010Assignee: TDK CorporationInventor: Mutsuko Nakano
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Patent number: 7556745Abstract: A sintered body for thermistor element of the invention is a sintered body for thermistor element containing Sr, Y, Mn, Al, Fe, and O, wherein not only respective liquid crystal phases of a perovskite type oxide and a garnet type oxide are contained, but also a liquid crystal phase of at least one of an Sr—Al based oxide and an Sr—Fe based oxide. FeYO3 and/or AlYO3 is selected as the foregoing perovskite type oxide, and at least one member selected from Y3Al5O12, Al2Fe3Y3O12, and Al3Fe2Y3O12 is selected as the foregoing garnet type oxide, respectively by the powder X-ray diffraction analysis.Type: GrantFiled: May 19, 2003Date of Patent: July 7, 2009Assignee: NGK Spark Plug Co., Ltd.Inventors: Takaaki Chosokabe, Masaki Iwaya, Naoki Yamada, Wakako Takano
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Publication number: 20080258861Abstract: A switching resistor for an electric switching device having an electrically conductive resistive material. The resistive material is a resistive material on a synthetic material basis.Type: ApplicationFiled: February 17, 2006Publication date: October 23, 2008Applicant: SIEMENS AKTIENGESELLSCHAFTInventors: Heiko Jahn, Lutz-Rudiger Janicke
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Patent number: 7432526Abstract: A semiconductor device has a heterostructure including a first layer of semiconductor oxide material. A second layer of semiconductor oxide material is formed on the first layer of semiconductor oxide material such that a two dimensional electron gas builds up at an interface between the first and second materials. A passivation layer on the outer surface stabilizes the structure. The device also has a source contact and a drain contact.Type: GrantFiled: December 20, 2005Date of Patent: October 7, 2008Assignee: Palo Alto Research Center IncorporatedInventors: Christian G. Van de Walle, Peter Kiesel, Oliver Schmidt
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Patent number: 7075404Abstract: A varistor is provided which can be driven at a low voltage, has a small leak current, and can realize a high ESD resistance and a high surge resistance. The varistor is formed using a ceramic composition for a varistor which contains zinc oxide as a primary component and sub-components including praseodymium at a content of 0.05 to 3.0 atomic percent of the total, cobalt at a content of 0.5 to 10 atom percent of the total, at least one of potassium, sodium, and lithium at a total content of 0.005 to 0.5 atom percent of the total, at least one of aluminum, gallium, and indium at a total content of 2×10?5 to 0.5 atom percent of the total, and zirconium at a content of 0.005 to 5.0 atom percent of the total.Type: GrantFiled: August 13, 2003Date of Patent: July 11, 2006Assignee: Murata Manufacturing Co., Ltd.Inventors: Sakyo Hirose, Akinori Nakayama, Kousuke Shiratsuyu
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Patent number: 7034652Abstract: The present invention provides a multifunction resistor having an improved voltage variable material (“VVM”). More specifically, the present invention provides a polymer VVM that has been formulated with a high percentage loading of conductive and/or semiconductive particles. A known length of the relatively conductive VVM is placed between adjacent electrodes to produce a desired Ohmic normal state resistance. When an electrostatic discharge event occurs, the VVM of the multifunctional resistor becomes highly conductive and dissipates the ESD threat. One application for this “resistor” is the termination of a transmission line, which prevents unwanted reflections and distortion of high frequency signals.Type: GrantFiled: July 10, 2002Date of Patent: April 25, 2006Assignee: Littlefuse, Inc.Inventors: Stephen J. Whitney, Hugh Hyatt, Louis Rector
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Patent number: 6554609Abstract: Nanostructured non-stoichiometric non-equilibrium materials are disclosed. Novel electromagnetic materials and their applications are discussed. More specifically, the specifications teach the use of nanotechnology and nanostructured materials for developing novel electrical devices and products.Type: GrantFiled: May 17, 2002Date of Patent: April 29, 2003Assignee: NanoProducts CorporationInventors: Tapesh Yadav, Roger Dirstine, John Alexander
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Patent number: 6459072Abstract: A glow plug for internal-combustion engines, comprising: a metal body (12); a metal sheath (24) having one closed end (26) and one open end (28); a terminal (30) extending through the open end (28) of the sheath (24); a conductive powder (34) set in electrical connection with one end (36) of the terminal (30) and with the sheath (24); and a layer (38) of insulating powder set between the aforesaid conductive powder (34) and the sheath (24) in an area between the closed end (26) of the sheath (24) and the end (36) of the terminal (30).Type: GrantFiled: August 6, 2001Date of Patent: October 1, 2002Assignee: Federal-Mogul Ignition SrlInventors: Ilaria Selmi, Sandro Goretti, Roberto Rossi
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Patent number: 6211496Abstract: The MoSi2 heating element has not been so resistant under the low-temperature heating, because the low-temperature oxidation, which is attributable to the grain boundary oxidation, occurred. In the present invention, long life under the low-temperature heating is attained by the following two structures. (1) The MoSi2 grains have a network structure and are linked three dimensionally. (2) The secondary, silica-bearing oxide or glass phase forms a net-like structure around the MoSi2 grains.Type: GrantFiled: February 19, 1999Date of Patent: April 3, 2001Assignee: Kabushiki Kaisha RikenInventors: Tetsuo Uchiyama, Wan Jiang
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Patent number: 6083426Abstract: A conductive paste having excellent printing properties, which can be used for manufacturing heat-resistant conductors and resistive elements, is described. Such a conductive paste can be obtained by preparing as a binder a polyimide precursor whose weight average degree of polymerization (n) ranges from 5 to 20, and mixing it with a solvent and a conductive powder. The polyimide precursor preferably is included in the range from 50 to 80 weight parts to 100 weight parts of the solvent. A polar solvent, or a mixed solvent including a polar solvent and a nonpolar solvent can be used. A preferable mixed solvent is a mixture of N-methyl-2-pyrrolidone and diethylene glycol dimethyl ether, in which the mixing volume ratio is preferably ranging from 2:8 to 9:1, more preferably, 2:8 to 3:7.Type: GrantFiled: June 8, 1999Date of Patent: July 4, 2000Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Yukihiro Shimasaki, Yusuke Ozaki, Masanaru Hasegawa, Toshiyuki Kitagawa
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Patent number: 5858533Abstract: A varistor and a PTC resistor formed from a composite material containing a polymer matrix and a filler. The varistor experiences two nonlinear changes caused by the current due to applied voltage, the varistor comprising a composite material comprising a filler and a polymer matrix, the filler consisting of particles of grained microstructure. The PTC resistor experiences a first nonlinear dependency of resistivity at a first PTC temperature resulting from an interaction of the filler and the polymer matrix and a second nonlinear dependency of resistivity at a second, lower PTC temperature resulting from the filler.Type: GrantFiled: January 15, 1997Date of Patent: January 12, 1999Assignee: ABB Research Ltd.Inventors: Felix Greuter, Ralf Strumpler
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Patent number: 5416462Abstract: An electrical resistance element having a resistance body between two contact terminals. The resistance body has PTC behavior and is composed of a polymer matrix and a filler component embedded in the polymer matrix. The filler component is composed of electrically conducting particles. Although the element is of simple and inexpensive construction, the resistance element is notable for good electrical conductivity in the low-resistance state and for a low response time for the PTC transition from the low-resistance to the high-resistance state. This is achieved as a result of the fact that at least some of the electrically conducting particles are formed as composite bodies having electrically conducting surfaces and/or as hollow or porous bodies composed of electrically conducting material. These particles have a lower specific density and/or lower specific heat capacity than solidly formed particles composed of conductive material.Type: GrantFiled: September 17, 1993Date of Patent: May 16, 1995Assignee: ABB Research Ltd.Inventors: Anton Demarmels, Felix Greuter, Ralf Strumpler
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Patent number: 5231370Abstract: Varistors and/or resistors that includes doped zinc oxide gel microspheres. The doped zinc oxide gel microspheres preferably have from about 60 to about 95% by weight zinc oxide and from about 5 to about 40% by weight dopants based on the weight of the zinc oxide. The dopants are a plurality of dopants selected from silver salts, boron oxide, silicon oxide and hydrons oxides of aluminum, bismuth, cobalt, chromium, manganese, nickel, and antimony.Type: GrantFiled: August 2, 1991Date of Patent: July 27, 1993Assignee: Cooper Industries, Inc.Inventors: Wesley D. Arnold, Jr., Walter D. Bond, Robert J. Lauf
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Patent number: 5228460Abstract: A heating element to provide heat to a tobacco flavor medium, for use in an electrical smoking article, by converting electrical energy to heat through the use of a material with electrically resistive properties is provided. The material is arranged in a radial array of blades with a current density profile such that a maximum area of each blade provides heat to the tobacco flavor medium dispersed thereon. The blade is generally U-shaped to assure dispersion of heat evenly to avoid hot spots along the blade and is tapered to reduce mass toward the mouth end of the heating element so as to maximize the heated area.Type: GrantFiled: December 12, 1991Date of Patent: July 20, 1993Assignee: Philip Morris IncorporatedInventors: F. Murphy Sprinkel, Everett C. Grollimund
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Patent number: 5218335Abstract: In an electronic circuit device, a thin film resistor is formed on a substrate and includes first regions including one kind of atom such as Cr and exhibiting an electric conductivity and a second region including a compound such as SiO.sub.2 composed of two kinds of atoms and exhibiting an insulating property. In the thin film resistor, the first regions are scattered in the second region and have an average particle size of 2 nm to 20 nm.Type: GrantFiled: April 24, 1991Date of Patent: June 8, 1993Assignee: Hitachi, Ltd.Inventors: Asao Nakano, Kiyoshi Ogata, Makiko Kohno, Yasunori Narizuka
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Patent number: 5182540Abstract: A resistor element includes a hollow cylindrical sintered body and a pair of electrodes formed on the upper and lower surfaces of the sintered body. The sintered body contains ferrite as a main constituent and contains 0.05 to 10% by volume of an insulator phase formed at the crystal grain boundary of the ferrite crystals. An insulating layer is formed to cover the side surface of the sintered body. The sintered body contains an oxide material selected from the group consisting of 0.005 to 2.0% by weight of bismuth oxide calculated in terms of Bi.sub.2 O.sub.3, 0.01 to 3.0% by weight and 0.005 to 2.0% by weight of silicon oxide and aluminum oxide calculated in terms of SiO.sub.2 and Al.sub.2 O.sub.3 respectively, and 0.01 to 3.5% by weight and 0.001 to 1.6% by weight of silicon oxide and calcium oxide calculated in terms of SiO.sub.2 and CaO, respectively.Type: GrantFiled: February 28, 1991Date of Patent: January 26, 1993Assignee: Kabushiki Kaisha ToshibaInventors: Naoki Shuto, Fumio Ueno, Yoshiko Goto, Akihiro Horiguchi, Mitsuo Kasori, Motomasa Imai
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Patent number: 5073689Abstract: The present invention provides a zirconia fiber-based or zirconia fiber-reinforced zirconia heating element which can be used in an oxidizing atmosphere at an elevated temperature.Type: GrantFiled: February 3, 1989Date of Patent: December 17, 1991Assignee: Shinagawa Shirorenga Kabushiki KaishaInventors: Katsuhiro Tabata, Masahiro Hayase, Hajime Asami, Hiroyuki Asakura, Kenji Mitsui
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Patent number: 4687903Abstract: A soldering iron bit is heated by an electrical heating element including a resistive element consisting of granular boron carbide packed in a quartz tube embedded in a piece of copper. A first power lead is electrically connected to the boron carbide at one end of the quartz tube. This first power lead passes through and is electrically insulated from the piece of copper. The second power lead is electrically connected to the boron carbide at the other end of the quartz tube, either directly or via the piece of copper. In use, connection of the first and second leads to an electrical power source causes the resistive element to generate heat in a very fast manner and to transmit this heat to the piece of copper. The piece of copper may be connected to or constitute the soldering bit and can be provided with a built-in thermostat comprising a meltable salt inserted in a hole provided in the piece of copper.Type: GrantFiled: September 27, 1985Date of Patent: August 18, 1987Inventor: Danny Zimmerman
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Patent number: 4418327Abstract: An arc limiting refractory resistive element is fabricated from aluminum oxide, carbon black and a sintering aid. The fabricating process includes compacting a mixture of the materials, sintering the compact in an inert atmosphere, then oxidizing the outer region of the sintered compact to form a non-conductive sheath around the electrically conductive material.Type: GrantFiled: September 17, 1981Date of Patent: November 29, 1983Assignees: GTE Laboratories Incorporated, GTE Prods. Corp.Inventors: Frank C. Palilla, Burton W. MacAllister, Jr., John F. McKenna
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Patent number: 4359414Abstract: An electric current regulating junction that can be electrically activated to a low resistance state in which it is capable of passing a relatively low reading current. The junction is capable of being activated electrically so as to be switched between low resistance and relatively high resistance states and vice versa. To switch from the low resistance to the high resistance state, one may apply relatively low currents (at least 10 times the magnitude of the reading current) in the form of a current-limited pulse, the pulse being regulated so that it will decay rapidly at the end. The junction comprises a normally insulative, electrically activatable composition having an electrical resistance greater than 10.sup.8 ohms through a layer 0.1-2,540 microns thick.Type: GrantFiled: October 29, 1980Date of Patent: November 16, 1982Assignee: E. I. Du Pont de Nemours and CompanyInventor: Sebastian V. R. Mastrangelo
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Patent number: 4292619Abstract: Corpuscular material which, while using a whether or not reacting binder, can be processed to resistor bodies. The material consists of corpuscular carrier material of inert oxidic material or, possibly, resistance-determining material, at the surface of which there is an oxidic resistance material retained by chemisorption, such as a noble metal compound. During heating the surface structure is retained. This starting material enables a considerable saving in noble metal compounds.Type: GrantFiled: December 29, 1978Date of Patent: September 29, 1981Assignee: U.S. Philips CorporationInventors: Cornelis A. H. A. Mutsaers, Alexander H. Boonstra
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Patent number: 4250397Abstract: The heating element includes a flexible graphite fiber-loaded impregnated paper saturated with a binder to ensure and maintain intimate electrical contact between the graphite fibers. In one form, two segments of the graphite fiber-loaded paper are coupled in series through a common bus bar and are electrically coupled to an SCR control circuit using a thermistor as a temperature responsive device. The graphite fiber-loaded paper with thermistor and electrical leads are encapsulated between cover sheets to provide an extremely thin highly flexible drapable therapeutic heating pad. Another form of heating pad includes providing the graphite fiber-loaded paper in the form of strips bonded to a plastic substrate. Electrical leads are attached and the substrate is enclosed by a cover sheet to provide a highly flexible heating pad. Two discrete methods of forming the latter heating pad are disclosed including silk screening and die pressing operations.Type: GrantFiled: June 1, 1977Date of Patent: February 10, 1981Assignee: International Paper CompanyInventors: Geoffrey I. Gray, John O. Freeborn
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Patent number: 4237441Abstract: Compositions which exhibit PTC behavior with a switching temperature (T.sub.s) above 0.degree. C., which have a resistivity at a temperature below T.sub.s of less than 7 ohm. cm, and which comprise a crystalline polymer and a particulate filler component which comprises carbon black having a particle size, D, which is from 20 to 150 millimicrons and a surface area S in m.sup.2 /gram such that S/D is not more than 10. The composition preferably has a peak resistivity of at least 1000 ohm. cm and is electrically stable when aged at elevated temperature. The quantity ##EQU1## is preferably less than 1, especially less than 0.5. Shaped articles of such compositions are prepared by a process in which the carbon black is dispersed in the molten polymer and the dispersion is then melt-shaped, the total energy used in preparing and melt-shaping the dispersion being 1 to 300 hp. hr. ft.sup.-3, preferably 1 to 100 hp. hr. ft.sup.-3, especially 1 to 50 hp. hr. ft.sup.-3.Type: GrantFiled: December 1, 1978Date of Patent: December 2, 1980Assignee: Raychem CorporationInventors: Peter V. van Konynenburg, Andrew Au, Chris Rauwendaal, Alan J. Gotcher
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Patent number: 4188607Abstract: A variable impedance device which serves to improve performance and reduce radio frequency emissions in electrically fired internal combustion engines employs a mixture of granulated or powdered bronze, or the constituents of bronze and of silica compacted and continually compressed for connection in series with the ignition wiring of an engine. The proportions of metal and silica are such that an irregular but complete conductive pathway is formed through the mixture. In preferred form the powders or granules are compressed within a fused silica lined sheath of stainless steel.Type: GrantFiled: December 1, 1978Date of Patent: February 12, 1980Inventors: David L. Cannom, Carlos M. Del Rio
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Patent number: 4125822Abstract: The presence of an organic liquid is detected by means of a probe which comprises a rubber-like material which is swellable in an organic liquid, which rubber-like material has electrically-conductive solid particles distributed therethrough, in such concentration as to touch each other.Type: GrantFiled: October 20, 1975Date of Patent: November 14, 1978Inventors: Benno Perren, Herbert Schreiber
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Patent number: 4019021Abstract: A resistance heating apparatus for rapidly heating a liquid or gas to a desired temperature includes a porous mat of fine electrically-conductive elongated elements selected from the group consisting of metal coated non-metal whiskers and polycrystalline metal whiskers electrically connected at their points of contact by metallization from the gaseous phase or by electron beam welding so as to be electrically conductive. The porous mat is disposed in and substantially fills all of the length of an electrically non-conductive tubular structure having an inlet opening at one end and a discharge opening at the opposite end. The tubular structure may be conical in shape with the inlet end being larger than the outlet end. Heating current may be supplied directly to the mat by electrodes connected thereto or the current may be induced therein from an induction means around the tubular structure.Type: GrantFiled: June 6, 1974Date of Patent: April 19, 1977Assignee: Schladitz-Whiskers, A.G.Inventor: Hermann J. Schladitz
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Patent number: 3982100Abstract: A monolithic electrical resistance heater element is produced from mixing particles of a conductive carbonaceous pyropolymer that have been deposited on a refractory metal oxide with a heat unifiable ceramic, such as alumina, cordierite, spodumene, etc., and then forming a resulting rigid "honeycomb type" of semiconductive ceramic substrate. The carbonaceous pyropolymer particles are preferably formed from heating an organic pyrolyzable substance in contact with alumina particles, or other metal oxide particulates, at a temperature above about 400.degree. C.Type: GrantFiled: October 8, 1974Date of Patent: September 21, 1976Assignee: Universal Oil Products CompanyInventor: George L. Hervert