US2645701A - Electrical resistor and resistance elements therefor - Google Patents
Electrical resistor and resistance elements therefor Download PDFInfo
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- US2645701A US2645701A US225478A US22547851A US2645701A US 2645701 A US2645701 A US 2645701A US 225478 A US225478 A US 225478A US 22547851 A US22547851 A US 22547851A US 2645701 A US2645701 A US 2645701A
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- fibre
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- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 50
- 229910052697 platinum Inorganic materials 0.000 claims description 25
- 238000004519 manufacturing process Methods 0.000 claims description 10
- 238000010304 firing Methods 0.000 claims description 5
- 239000000341 volatile oil Substances 0.000 claims description 4
- 239000002904 solvent Substances 0.000 claims description 2
- 239000000835 fiber Substances 0.000 description 27
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 26
- 229910052737 gold Inorganic materials 0.000 description 26
- 239000010931 gold Substances 0.000 description 26
- 239000011521 glass Substances 0.000 description 20
- 239000000463 material Substances 0.000 description 19
- 229910052751 metal Inorganic materials 0.000 description 17
- 239000002184 metal Substances 0.000 description 17
- 230000001464 adherent effect Effects 0.000 description 13
- 238000000576 coating method Methods 0.000 description 13
- 239000011248 coating agent Substances 0.000 description 12
- 230000002238 attenuated effect Effects 0.000 description 11
- JUWSSMXCCAMYGX-UHFFFAOYSA-N gold platinum Chemical compound [Pt].[Au] JUWSSMXCCAMYGX-UHFFFAOYSA-N 0.000 description 11
- 229910045601 alloy Inorganic materials 0.000 description 10
- 239000000956 alloy Substances 0.000 description 10
- 238000004804 winding Methods 0.000 description 10
- 229910001260 Pt alloy Inorganic materials 0.000 description 9
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 8
- 150000001875 compounds Chemical class 0.000 description 8
- 239000003921 oil Substances 0.000 description 8
- 239000000203 mixture Substances 0.000 description 7
- 239000005416 organic matter Substances 0.000 description 6
- 229910052797 bismuth Inorganic materials 0.000 description 5
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 239000011877 solvent mixture Substances 0.000 description 5
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 4
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 4
- 244000178870 Lavandula angustifolia Species 0.000 description 4
- 235000010663 Lavandula angustifolia Nutrition 0.000 description 4
- 239000000020 Nitrocellulose Substances 0.000 description 4
- 241000779819 Syncarpia glomulifera Species 0.000 description 4
- FJWGYAHXMCUOOM-QHOUIDNNSA-N [(2s,3r,4s,5r,6r)-2-[(2r,3r,4s,5r,6s)-4,5-dinitrooxy-2-(nitrooxymethyl)-6-[(2r,3r,4s,5r,6s)-4,5,6-trinitrooxy-2-(nitrooxymethyl)oxan-3-yl]oxyoxan-3-yl]oxy-3,5-dinitrooxy-6-(nitrooxymethyl)oxan-4-yl] nitrate Chemical compound O([C@@H]1O[C@@H]([C@H]([C@H](O[N+]([O-])=O)[C@H]1O[N+]([O-])=O)O[C@H]1[C@@H]([C@@H](O[N+]([O-])=O)[C@H](O[N+]([O-])=O)[C@@H](CO[N+]([O-])=O)O1)O[N+]([O-])=O)CO[N+](=O)[O-])[C@@H]1[C@@H](CO[N+]([O-])=O)O[C@@H](O[N+]([O-])=O)[C@H](O[N+]([O-])=O)[C@H]1O[N+]([O-])=O FJWGYAHXMCUOOM-QHOUIDNNSA-N 0.000 description 4
- 239000003365 glass fiber Substances 0.000 description 4
- 239000001102 lavandula vera Substances 0.000 description 4
- 235000018219 lavender Nutrition 0.000 description 4
- LQNUZADURLCDLV-UHFFFAOYSA-N nitrobenzene Chemical compound [O-][N+](=O)C1=CC=CC=C1 LQNUZADURLCDLV-UHFFFAOYSA-N 0.000 description 4
- 229920001220 nitrocellulos Polymers 0.000 description 4
- 229940079938 nitrocellulose Drugs 0.000 description 4
- 239000001739 pinus spp. Substances 0.000 description 4
- 229910052703 rhodium Inorganic materials 0.000 description 4
- 239000010948 rhodium Substances 0.000 description 4
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 description 4
- 229940036248 turpentine Drugs 0.000 description 4
- 229910010272 inorganic material Inorganic materials 0.000 description 3
- 239000011147 inorganic material Substances 0.000 description 3
- 150000003058 platinum compounds Chemical class 0.000 description 3
- 229940045985 antineoplastic platinum compound Drugs 0.000 description 2
- JHXKRIRFYBPWGE-UHFFFAOYSA-K bismuth chloride Chemical compound Cl[Bi](Cl)Cl JHXKRIRFYBPWGE-UHFFFAOYSA-K 0.000 description 2
- 229910010293 ceramic material Inorganic materials 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 229920002678 cellulose Polymers 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 229920002050 silicone resin Polymers 0.000 description 1
- 238000005476 soldering Methods 0.000 description 1
- 239000002966 varnish Substances 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01C—RESISTORS
- H01C17/00—Apparatus or processes specially adapted for manufacturing resistors
- H01C17/06—Apparatus or processes specially adapted for manufacturing resistors adapted for coating resistive material on a base
- H01C17/20—Apparatus or processes specially adapted for manufacturing resistors adapted for coating resistive material on a base by pyrolytic processes
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01C—RESISTORS
- H01C17/00—Apparatus or processes specially adapted for manufacturing resistors
- H01C17/04—Apparatus or processes specially adapted for manufacturing resistors adapted for winding the resistive element
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01C—RESISTORS
- H01C3/00—Non-adjustable metal resistors made of wire or ribbon, e.g. coiled, woven or formed as grids
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01C—RESISTORS
- H01C7/00—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49002—Electrical device making
- Y10T29/49082—Resistor making
- Y10T29/49087—Resistor making with envelope or housing
- Y10T29/49096—Resistor making with envelope or housing with winding
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
- Y10T428/2913—Rod, strand, filament or fiber
- Y10T428/2933—Coated or with bond, impregnation or core
- Y10T428/294—Coated or with bond, impregnation or core including metal or compound thereof [excluding glass, ceramic and asbestos]
Definitions
- 'I'h1s invention relates to improvements in and relating to electrical resistors and resistance elements therefor and is more particularly concerned with the provision of an improved resistance element and a resistor incorporating such an element, suitable for use inthe electronic art.
- resistors having a resistance value of from 0.1- megohms are common- 1y required, but for particular applications it may be necessary to employ resistors having values of several hundred megohms.
- the expression high resistance value or high value as employed herein, is intended to embrace resistance values ranging from one-tenth of a megohm to several hundred megohms.
- resistors for use in radio and similar equipment are at present marketed, but all of them suffer from certain inherent disadvantages, which detract from their efficient use in modern electronic apparatus.
- a resistor which shall have a high resistance value and a stable resistance, shall be substantially noise free and have a low, preferably positive, temperature coefiicient of resistance and which shall at the same time be compact and readily handlable. So far as We are aware, there is no resistor at present available which fully meets these requirements.
- the principal object of this invention is to provide an improved resistance element, by means of which resistors may be prepared which exhibit in use an improved performance and which more adequately comply with the requirements of the electrical industry than do existing types of resistors.
- Another object of the invention is to provide an improved resistance element by means of which a resistor having the characteristics of high value, improved stability and substantial freedom from noise can be prepared.
- Another object is to provide a metal film resistor which is compact, and, at the same time, exhibits the characteristics of stability combined with a low temperature coefiicient of resistance.
- a further object is to provide a resistance element by means of which a high value resistor may be obtained without resort to helical groov-
- a resistance element by means of which a high value resistor may be obtained without resort to helical groov-
- Figure 1 shows a partly completed high value resistor embodying the features of our invention
- Figure 2 shows the completed resistor
- Figure 3 shows one method of forming the metallised filament or fibre constituting the resistance element.
- Our invention therefore, broadly comprises, as an article of manufacture, an electric resistance clement comprising'a fiament, strand or fibre of non-conductive heat-resisting inorganic material having on the outer surface thereof a firmly adherent relatively thick fired-on film or layer consisting wholly or predominantly of a metal or alloy selected from the group consisting of gold, platinum and goldzplatinum alloys.
- heat-resisting material as used herein and in the claims is meant a material capable of withstanding a firing temperature of at least .00 C. and by relatively thick film or layer” is meant a film or layer haivng a resistance of between and 1000 ohms/sq.
- the material of which the filament, strand or fibre is formed may advantageously be glass or a glass-like material and of these materials we prefer to use glass.
- the conducting film or layer is formed of a gold platinum alloy, we have found that an 80:20 goldzplatinum alloy will give excellent results. A resistor formed with this alloy will exhibit a high resistivity and a low temperature coefficient of resistance.
- an electrical resistance element which comprises the steps of applying to the surface of a filament, strand or fibre of non-conductive heatresisting inorganic material a coating of a solution containing a compound of gold or platinum, or a mixture of gold and platinum compounds dissolved therein and subsequently heating the coated filament, strand or fibre to decompose the compound or compounds and cause the resulting metal or alloy film to adhere firmly thereto.
- a resistance element embodying the novel features of our invention may be made by applying to the surface of a filament, strand or fibre of non-conductive heat-resisting inorganic material and preferably having an inherent flexibility and strength such as to enable it to be wound on a former, a coating of a solution containing a compound of gold or platinum or a mixture of gold and platinum compounds dissolved therein and subsequently heatin' the coated filament, strand or fibre to decompose the compound or compounds and cause the resulting metal or alloy film to adhere firmly thereto.
- the solution may, for example, comprise a mixture of a gold and/ or a platinum compound and. a cellulose derivative dissolved in a suitable solvent or solvent mixture to which is preferably added an adhesion promoting agent or flux.
- W e have found a solution of platinic chloride, bismuth chloride and nitro-cellulose in a solvent mixture comprising acetone and alcohol, which, on firing, will produce a platinum film, to be satisfactory for our purpose.
- a temperature coefiicient lower than that given by a film of platinum alone may, however, be obtained by the use of a solution consisting of the sulphoresinates of gold and platinum (in the proportion of 4 parts of gold to one part of platinum) and bismuth resinate in an essential oil solvent mixture.
- the filament, strand or fibre may advantageously be coated by passing it through a bath containing the desired coating solution or over, and in contact with, a pad moistened with the said solution.
- Example H Percent Gold (as sulpho-resinate) 7.0 Rhodium (as sulpho-reslnate) W 0.1 Bismuth (as resinate) 0.2 Oil of turpentine 43.0 Oil of lavender 10.0
- Example 111 Perce .t Gold (as sulpho-resinate) 5.6 Platinum (as sulpho-resinate) 1.4 Rhodium 0.1 Bismuth (as resinate) 0.2 Oil of turpentine 43.0 Oil of lavender 1..0 Nitro-benzol 10.0 Colophony 21.7
- This solution when fired, will produce a film or layer consisting of a gold-platinum alloy.
- a further coating or further coatings of the solution may be applied depending on the required final thickness and resistance of the metallising film or layer.
- the latter is wound on an insulating former, which is preferably of circular cross-section, although other cross-sections may be employed.
- an insulating former which is preferably of circular cross-section, although other cross-sections may be employed.
- the method may, advantageously, be carried out as a continuous process comprising drawing or feeding a continuous length of filament or fibre through a gold, platinum or gold and platinum metallising solution, passing the coated fibre through a furnace to cause the organic matter in the coating to burn away and leave a firmly adherent film or layer of metal or alloy on the fibre and then winding the metallised fibre on to a reel or drum.
- the required length of metallised filament or fibre is wound from th drum on to an insulating former, e. g. of suitable ceramic material, and external connections are made to the element in any suitable manner.
- an insulating former e. g. of suitable ceramic material
- the resistor consists of a former i of ceramic material on which is wound a resistance element in the form of a glass fibre 2, which has been previously metallised in accordance with this invention.
- a former i of ceramic material on which is wound a resistance element in the form of a glass fibre 2, which has been previously metallised in accordance with this invention.
- On each end of the former i is a 3 to which the free ends l of the metallised fibre 2 are attached, for example by soldering. as shown at 5.
- 6 are the usual lead wires which are soldered to the outer ends of the caps 3 at for connecting the resistor in an electro c circuit.
- the completed resistor is covered with a lo er of a silicone resin varnish 8 (Figure 2) or other megohm may be constituted as follows:
- Fibre (glass) 0.001 in. dia. Resistance of film 100 ohms/square.
- Another resistor embodying the invention and having a resistance value of 10 megohms may be constituted as follows:
- Fibre (glass) 0.001 dia. Resistance of film 300 ohms/square. Resistance of 1 inch of metal- 95400 ohms.
- Figure 3 illustrates diagrammatically the preferred manner of making a resistance element embodying the features of the invention.
- 9 represents a reel or drum upon which is wound a length of glass fibre 10.
- the fibre I is drawn from the drum 9 and passes between a pair of superposed felt pads II and !2, supported in a vessel or bath [3 containing the desired metallising solution 14, the pad II being partly immersed in the said solution.
- the glass fibre l0 when it emerges from the vessel 13, is thus covered with a thin coating of the metallising solution Hi.
- the coated fibre 10 now passes into a muflie furnace containing an electric resistance heating element l6, where the coated fibre is first heated to a temperature Within a range of 450-550" C., the particular temperature depending on the particular composition of the glass constituting the fibre, to burn awai the organic matter contained in the coating solution and cause the metal in the solution to adhere firmly thereto and is then annealed, after which the now metallised and annealed fibre l0 passes out of the furnace and is wound on to a drum l'l.
- a method of making an electrical resistance element which comprises the steps of applying to a glass filament a solution of the sulphoresinate of at least one metal selected from the group consisting of gold and platinum dissolved in an essential oil solvent mixture, firing said coated filament at a temperature sufficient to burn away the organic matter and cause an adherent metallic film to adhere to'said filament, and then winding a continuous length of said filament around the outer periphery of an insulating former, and in which the solution has the following composition, namely:
- An electrical resistance element comprising an insulating former carrying a conductive element comprising a single continuous length of filament of a material selected from the group consisting of glass and glass-like materials having on the outer surface thereof a firmly adherent relatively thick substantiall uniform film of a gold platinum alloy wound around the outer periphery of said former for a plurality of turns in close proximity to each other, thereby providing an attenuated current path.
- An electrical resistance element comprising an insulating former carrying a conductive element comprising a single continuous length of glass filament having on the outer surface thereof a firmly adherent relatively thick substantially uniform film consisting of a goldzplatinum alloy wound around the outer periphery of said former for a plurality of turns in close proximity to each other.
- a method of making an electrical resistance element which comprises the steps of applying to the outer surface of a continuous filament of glass a substantially uniform layer consisting of gold-platinum alloy and then winding a continuous length of said coated filament around the outer periphery of a cylindrical insulating former for a plurality of turns in close proximity to each other thereby providing an attenuated current path.
- a method of making an electrical resistance element which comprises the steps of drawing a glass filament through a bath containing a solution consisting of platinic chloride, bismuth chloride and nitrocellulose dissolved in alcohol and acetone to form a coating of said solution on said filament; heating said coated filament to burn away the organic matter in said coating and cause a film of platinum to adhere firmly to said filament; and then winding a continuous length of said filament around the outer periphery of an insulating former for a plurality of turns in close proximity to each other, thereby providing an attenuated current path.
- a method of making an electrical resistance element which comprises the steps of applying to a continuous filament of glass a solution of the sulphoresinate of metal selected from the group consisting of gold, platinum, and goldplatinum alloys dissolved in an essential oil solvent mixture; firing said coated filament at a temperature sufiicient to burn away the organic matter and cause anadherent metallic film to adhere to said filament; and then winding a continuous length of said filament around the outer periphery of an insulating former for a plurality of turns in close proximity to each other, thereby providing an attenuated current path.
- An electrical resistance element comprising an insulating former carrying a conductive element comprising a continuous length of filament of a material selected from the group consisting of glass and glass-like materials having on the outer surface thereof a firmly adherent, relatively thick, substantially uniform film consisting of metal selected from the group consisting of gold, platinum, and gold-platinum alloys wound around the outer periphery of said former for a plurality of turns in close proximity to each other, thereby providing an attenuated current path.
- An electrical resistance element comprising an insulating former carrying a conductive element comprising a continuous length of filament of a material selected from the group consisting of glass and glass-like materials having on the outer surface thereof a firmly adherent, relatively thick, substantially uniform film of gold Wound around the outer periphery of said former for a plurality of turns in close proximity to each other, thereby providing an attenuated current path.
- An electrical resistance element comprising an insulating former carrying a conductive element comprising a single continuous length of filament of a material selected from the group consisting of glass and glass-like materials having on the outer surface thereof a firmly adherent, relatively thick, substantially uniform film of platinum wound around the outer periphery of said former for a plurality of turns in close proximity to each other, thereby providing an attenuated current path.
- An electrical resistance element comprising an insulating former carrying a conductive element comprising a single continuous length of glass filament having on the outer surface thereof a firmly adherent, relatively thick, substantially uniform film consisting of metal selected from the group consisting of gold, platinum, and gold-platinum alloys wound around the outer periphery of said former for a plurality of turns in close proximity to each other, thereby providing an attenuated current path.
- An electrical resistance element comprising an insulating former carrying a conductive element comprising a single continuous length of glass filament having on the outer surface thereof a firmly adherent, relatively thick, substantially uniform film consisting of gold wound around the outer periphery of said former for a plurality of turns in close proximity to each other.
- An electrical resistance element comprising an insulating former carrying a conductive element comprising a single continuous length of glass filament having on the outer surface thereof a firmly adherent, relatively thick, substantially uniform film consisting of platinum wound around the outer periphery of said former for a plurality of turns in close proximity to each other.
- a method of making an electrical resistance element which comprises the steps of applying to the outer surface of a continuous filament of a material selected from the group consisting of glass and glass-like materials a substantially uniform layer consisting of metal selected from the group, consisting of gold, platinum, and goldplatinum alloys, and then winding a continuous length of said coated filament around the outer periphery of an insulating former for a plurality of turns in close proximity to each other, thereby providing an attenuated current path.
- a method of making an electrical resistance a element which comprises the steps of applying to the outer surface of a continuous filament of a material selected from the group consisting of glass and glass-like materials a solution containing a compound of metal selected from the group consisting of gold, platinum, and gold-platinum alloys dissolved therein; heating said coated filament to decompose at least said compound and cause a metallic film to adhere to said filament; and then winding a continuous length of said coated filament around the outer periphery of an insulating former for a plurality of trans in close proximity to each other, thereby providing an attenuated current path.
- a method of making an electrical resistance element which comprises the steps of winding around the outer periphery of a cylindrical insulating former for a plurality of turns in close proximity to each other, a continuous length of a filament of a material selected from the group consisting of glass and glass-like materials having on its outer surface a firmly adherent, relatively thick, substantially uniform film consisting of metal selected from the group consisting of gold, platinum, and gold-platinum alloys, thereby providing an attenuated current path, and providing a stable resistance having a predetermined high constant value.
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Description
July 4, 1953 F. E. KERRIDGE ETAL 2,645,701
ELECTRICAL RESISTOR AND RESISTANCE ELEMENTS THEREFOR Filed May 10. 1951 [n Venlbrs fkA/VK. E. AEkR/DGE M/Cf/AEL BEN/AM GRAHAM PEARCE.
Adv/hey:
Patented July '14, 1953 ELECTRICAL RESISTOR AND RESISTANCE ELEMENTS THEREFOR Frank Enoch Kerridge and Michael Belham, London, andGraham Pearce, Kingsthorpe, North- 'ampton,- England,
assignors to Johnson,
Matthey & Company Limited, London, England, and Painton & Company Limited, Kingsthorpe, Northampton, England, both British companies Application May 10, 1951, Serial No. 225,478 In Great Britain January 25, 1950 17 Claims. 1
'I'h1s invention relates to improvements in and relating to electrical resistors and resistance elements therefor and is more particularly concerned with the provision of an improved resistance element and a resistor incorporating such an element, suitable for use inthe electronic art.
For many purposes, resistors having a resistance value of from 0.1- megohms are common- 1y required, but for particular applications it may be necessary to employ resistors having values of several hundred megohms. The expression high resistance value or high value as employed herein, is intended to embrace resistance values ranging from one-tenth of a megohm to several hundred megohms. H
Various types of resistors for use in radio and similar equipment are at present marketed, but all of them suffer from certain inherent disadvantages, which detract from their efficient use in modern electronic apparatus. There is a constant demand from the electrical industry for a resistor, which shall have a high resistance value and a stable resistance, shall be substantially noise free and have a low, preferably positive, temperature coefiicient of resistance and which shall at the same time be compact and readily handlable. So far as We are aware, there is no resistor at present available which fully meets these requirements.
The principal object of this invention is to provide an improved resistance element, by means of which resistors may be prepared which exhibit in use an improved performance and which more adequately comply with the requirements of the electrical industry than do existing types of resistors.
Another object of the invention is to provide an improved resistance element by means of which a resistor having the characteristics of high value, improved stability and substantial freedom from noise can be prepared.
Another object is to provide a metal film resistor which is compact, and, at the same time, exhibits the characteristics of stability combined with a low temperature coefiicient of resistance.
A further object is to provide a resistance element by means of which a high value resistor may be obtained without resort to helical groov- The manner in which the above and other objects are attained will be readily understood from the following detailed description, taken in con- Junction with the lacc mpanyingy drawings,
which are given merely by way of example and are not to be regarded as in any way limitative, the scope of the invention being defined by the appended claims.
In the drawings, Figure 1 shows a partly completed high value resistor embodying the features of our invention, Figure 2 shows the completed resistor and Figure 3 shows one method of forming the metallised filament or fibre constituting the resistance element.
During the course of extensive research carried out by us in an endeavour to meet the above I requirements, experiments were conducted with resistance elements composed of metallic films applied to suitable insulating bases and it was found that, whilst a thin metallic film would enable a high resistance value to be obtained, the resistance was not stable, whereas a relatively thick metallic film, whilst providing the required degree of stability, would not enable a high value resistor to be obtained unless the element were of such a length as to be impracticable for electronic purposes.
The problem that confronted us, therefore was to provide a resistance element, the current con ducting path of which would besufiiciently thick to produce a stable resistance and at the same time could be made of sumcient length to give a high value in a finished resistor, without the latter being unduly bulky or elongated As the result of our investigations, we have found that a satisfactory resistance element can be obtained by coating a filament, strand or fibre of non-conducting material with a relatively thick film composed of a selected metal or metals, the filament, strand or fibre being of such a nature that the metal coating can be fired thereon and preferably having sufiicient flexibility and strength as to render it capable of being wound on a small diameter former, such as a A" diameter former commonly used for miniature resistors. By this means a compact resistor of readily handlable size having a stable resistance and a high value can be obtained.
Our invention, therefore, broadly comprises, as an article of manufacture, an electric resistance clement comprising'a fiament, strand or fibre of non-conductive heat-resisting inorganic material having on the outer surface thereof a firmly adherent relatively thick fired-on film or layer consisting wholly or predominantly of a metal or alloy selected from the group consisting of gold, platinum and goldzplatinum alloys.
By heat-resisting material as used herein and in the claims is meant a material capable of withstanding a firing temperature of at least .00 C. and by relatively thick film or layer" is meant a film or layer haivng a resistance of between and 1000 ohms/sq.
The material of which the filament, strand or fibre is formed may advantageously be glass or a glass-like material and of these materials we prefer to use glass.
If the conducting film or layer is formed of a gold platinum alloy, we have found that an 80:20 goldzplatinum alloy will give excellent results. A resistor formed with this alloy will exhibit a high resistivity and a low temperature coefficient of resistance.
Other metals, in addition to gold and/or platinum, may, if desired, be included in the conducting film or layer.
According to a further feature of the invention, we provide a method for the manufacture of an electrical resistance element which comprises the steps of applying to the surface of a filament, strand or fibre of non-conductive heatresisting inorganic material a coating of a solution containing a compound of gold or platinum, or a mixture of gold and platinum compounds dissolved therein and subsequently heating the coated filament, strand or fibre to decompose the compound or compounds and cause the resulting metal or alloy film to adhere firmly thereto.
A resistance element embodying the novel features of our invention may be made by applying to the surface of a filament, strand or fibre of non-conductive heat-resisting inorganic material and preferably having an inherent flexibility and strength such as to enable it to be wound on a former, a coating of a solution containing a compound of gold or platinum or a mixture of gold and platinum compounds dissolved therein and subsequently heatin' the coated filament, strand or fibre to decompose the compound or compounds and cause the resulting metal or alloy film to adhere firmly thereto.
The solution may, for example, comprise a mixture of a gold and/ or a platinum compound and. a cellulose derivative dissolved in a suitable solvent or solvent mixture to which is preferably added an adhesion promoting agent or flux. W e have found a solution of platinic chloride, bismuth chloride and nitro-cellulose in a solvent mixture comprising acetone and alcohol, which, on firing, will produce a platinum film, to be satisfactory for our purpose.
A temperature coefiicient lower than that given by a film of platinum alone may, however, be obtained by the use of a solution consisting of the sulphoresinates of gold and platinum (in the proportion of 4 parts of gold to one part of platinum) and bismuth resinate in an essential oil solvent mixture.
The filament, strand or fibre may advantageously be coated by passing it through a bath containing the desired coating solution or over, and in contact with, a pad moistened with the said solution.
The following are examples of solutions which may be employed to form a resistance element in accordance with the invention by coating a glass fibre therewith and then heating to burn away the organic matter and leave an adherent gold or platinum or gold platinum alloy film on the fibre. It is to be understood, however, that the invention is, in no way, limited to these examples.
4 Example I Percen Platinic chloride 5 Alcohol 8 Nitro-cellulose 8 Acetone This solution, when fired, will produce a film or layer of platinum.
Example H Percent Gold (as sulpho-resinate) 7.0 Rhodium (as sulpho-reslnate) W 0.1 Bismuth (as resinate) 0.2 Oil of turpentine 43.0 Oil of lavender 10.0
Nitro-benzol 10.0 Colophony 21.7
This solution, when fired, will produce a film or layer of gold.
Example 111 Perce .t Gold (as sulpho-resinate) 5.6 Platinum (as sulpho-resinate) 1.4 Rhodium 0.1 Bismuth (as resinate) 0.2 Oil of turpentine 43.0 Oil of lavender 1..0 Nitro-benzol 10.0 Colophony 21.7
This solution, when fired, will produce a film or layer consisting of a gold-platinum alloy.
If desired, a further coating or further coatings of the solution may be applied depending on the required final thickness and resistance of the metallising film or layer.
In forming a high value resistor with the of our improved resistance element, the latter is wound on an insulating former, which is preferably of circular cross-section, although other cross-sections may be employed. In this marine. owing to the extreme attenuation of the conducting path, a high value resistor of readily hand-- lable size may be obtained.
The method may, advantageously, be carried out as a continuous process comprising drawing or feeding a continuous length of filament or fibre through a gold, platinum or gold and platinum metallising solution, passing the coated fibre through a furnace to cause the organic matter in the coating to burn away and leave a firmly adherent film or layer of metal or alloy on the fibre and then winding the metallised fibre on to a reel or drum.
To complete a resistor embodying our proved resistance element, the required length of metallised filament or fibre is wound from th drum on to an insulating former, e. g. of suitable ceramic material, and external connections are made to the element in any suitable manner.
Referring now to Figure 1 of the drawings, the resistor consists of a former i of ceramic material on which is wound a resistance element in the form of a glass fibre 2, which has been previously metallised in accordance with this invention. On each end of the former i is a 3 to which the free ends l of the metallised fibre 2 are attached, for example by soldering. as shown at 5. 6 are the usual lead wires which are soldered to the outer ends of the caps 3 at for connecting the resistor in an electro c circuit.
The completed resistor is covered with a lo er of a silicone resin varnish 8 (Figure 2) or other megohm may be constituted as follows:
Fibre (glass) 0.001 in. dia. Resistance of film 100 ohms/square.
Resistance of 1 inch of 31800 ohms.
metallised fibre.
Length required for 1 31.4 inches.
megohm.
Former 0.160 in. dia.
Number of turns -1 63.
Pitch of turns 0.004 in.
Length of winding /4 in.
Another resistor embodying the invention and having a resistance value of 10 megohms may be constituted as follows:
Fibre (glass) 0.001 dia. Resistance of film 300 ohms/square. Resistance of 1 inch of metal- 95400 ohms.
lised fibre. Length of fibre required for 10 104.6".
megohms. Former A dia. Number of turns 133. Pitch of turns 0.004". Length of winding 0.53".
Figure 3 illustrates diagrammatically the preferred manner of making a resistance element embodying the features of the invention.
Referring now to this Figure 3, 9 represents a reel or drum upon which is wound a length of glass fibre 10. The fibre I is drawn from the drum 9 and passes between a pair of superposed felt pads II and !2, supported in a vessel or bath [3 containing the desired metallising solution 14, the pad II being partly immersed in the said solution.
The glass fibre l0, when it emerges from the vessel 13, is thus covered with a thin coating of the metallising solution Hi. The coated fibre 10 now passes into a muflie furnace containing an electric resistance heating element l6, where the coated fibre is first heated to a temperature Within a range of 450-550" C., the particular temperature depending on the particular composition of the glass constituting the fibre, to burn awai the organic matter contained in the coating solution and cause the metal in the solution to adhere firmly thereto and is then annealed, after which the now metallised and annealed fibre l0 passes out of the furnace and is wound on to a drum l'l.
It is to be understood that whilst, in the above. one embodiment of the invention and the manner in which it is to be performed has been described, modification maybe made to the details thereof, without departing from the spirit of the invention.
What we claim is:
1. A method of making an electrical resistance element which comprises the steps of applying to a glass filament a solution of the sulphoresinate of at least one metal selected from the group consisting of gold and platinum dissolved in an essential oil solvent mixture, firing said coated filament at a temperature sufficient to burn away the organic matter and cause an adherent metallic film to adhere to'said filament, and then winding a continuous length of said filament around the outer periphery of an insulating former, and in which the solution has the following composition, namely:
Percent Gold (as su1ph0-resinate) 5.6 Platinum (as sulpho-resinate) 1.4 Rhodium 0.1 Bismuth (as resinate) 0.2 Oil of turpentine 43.0 Oil of lavender 18.0 Nitro-benzol 10.0 Colophony 21.7
2. An electrical resistance element comprising an insulating former carrying a conductive element comprising a single continuous length of filament of a material selected from the group consisting of glass and glass-like materials having on the outer surface thereof a firmly adherent relatively thick substantiall uniform film of a gold platinum alloy wound around the outer periphery of said former for a plurality of turns in close proximity to each other, thereby providing an attenuated current path. 7
3. An electrical resistance element comprising an insulating former carrying a conductive element comprising a single continuous length of glass filament having on the outer surface thereof a firmly adherent relatively thick substantially uniform film consisting of a goldzplatinum alloy wound around the outer periphery of said former for a plurality of turns in close proximity to each other.
4. A method of making an electrical resistance element which comprises the steps of applying to the outer surface of a continuous filament of glass a substantially uniform layer consisting of gold-platinum alloy and then winding a continuous length of said coated filament around the outer periphery of a cylindrical insulating former for a plurality of turns in close proximity to each other thereby providing an attenuated current path.
5. A method of making an electrical resistance element which comprises the steps of drawing a glass filament through a bath containing a solution consisting of platinic chloride, bismuth chloride and nitrocellulose dissolved in alcohol and acetone to form a coating of said solution on said filament; heating said coated filament to burn away the organic matter in said coating and cause a film of platinum to adhere firmly to said filament; and then winding a continuous length of said filament around the outer periphery of an insulating former for a plurality of turns in close proximity to each other, thereby providing an attenuated current path.
6. A method according to claim 5 in which the solution has the following composition, namely Percent Platinic chloride 8 Alcohol 8 Nitro-cellulose 8 Acetone 1 76 7. A method of making an electrical resistance element which comprises the steps of applying to a continuous filament of glass a solution of the sulphoresinate of metal selected from the group consisting of gold, platinum, and goldplatinum alloys dissolved in an essential oil solvent mixture; firing said coated filament at a temperature sufiicient to burn away the organic matter and cause anadherent metallic film to adhere to said filament; and then winding a continuous length of said filament around the outer periphery of an insulating former for a plurality of turns in close proximity to each other, thereby providing an attenuated current path.
8. A method according to claim 7 in which the solution has the following composition, namely Percent Gold (as sulpho-resinate) 7.0 Rhodium (as sulpho-resinate) 0.1 Bismuth (as resinate) 0.2 Oil of turpentine 43.0 Oil of lavender 18.0 Nitro-benzol 10.0 Colophony 21.7
9. An electrical resistance element comprising an insulating former carrying a conductive element comprising a continuous length of filament of a material selected from the group consisting of glass and glass-like materials having on the outer surface thereof a firmly adherent, relatively thick, substantially uniform film consisting of metal selected from the group consisting of gold, platinum, and gold-platinum alloys wound around the outer periphery of said former for a plurality of turns in close proximity to each other, thereby providing an attenuated current path.
10. An electrical resistance element comprising an insulating former carrying a conductive element comprising a continuous length of filament of a material selected from the group consisting of glass and glass-like materials having on the outer surface thereof a firmly adherent, relatively thick, substantially uniform film of gold Wound around the outer periphery of said former for a plurality of turns in close proximity to each other, thereby providing an attenuated current path.
11. An electrical resistance element comprising an insulating former carrying a conductive element comprising a single continuous length of filament of a material selected from the group consisting of glass and glass-like materials having on the outer surface thereof a firmly adherent, relatively thick, substantially uniform film of platinum wound around the outer periphery of said former for a plurality of turns in close proximity to each other, thereby providing an attenuated current path.
12. An electrical resistance element comprising an insulating former carrying a conductive element comprising a single continuous length of glass filament having on the outer surface thereof a firmly adherent, relatively thick, substantially uniform film consisting of metal selected from the group consisting of gold, platinum, and gold-platinum alloys wound around the outer periphery of said former for a plurality of turns in close proximity to each other, thereby providing an attenuated current path.
13. An electrical resistance element comprising an insulating former carrying a conductive element comprising a single continuous length of glass filament having on the outer surface thereof a firmly adherent, relatively thick, substantially uniform film consisting of gold wound around the outer periphery of said former for a plurality of turns in close proximity to each other.
14. An electrical resistance element comprising an insulating former carrying a conductive element comprising a single continuous length of glass filament having on the outer surface thereof a firmly adherent, relatively thick, substantially uniform film consisting of platinum wound around the outer periphery of said former for a plurality of turns in close proximity to each other.
15. A method of making an electrical resistance element which comprises the steps of applying to the outer surface of a continuous filament of a material selected from the group consisting of glass and glass-like materials a substantially uniform layer consisting of metal selected from the group, consisting of gold, platinum, and goldplatinum alloys, and then winding a continuous length of said coated filament around the outer periphery of an insulating former for a plurality of turns in close proximity to each other, thereby providing an attenuated current path.
16. A method of making an electrical resistance a element which comprises the steps of applying to the outer surface of a continuous filament of a material selected from the group consisting of glass and glass-like materials a solution containing a compound of metal selected from the group consisting of gold, platinum, and gold-platinum alloys dissolved therein; heating said coated filament to decompose at least said compound and cause a metallic film to adhere to said filament; and then winding a continuous length of said coated filament around the outer periphery of an insulating former for a plurality of trans in close proximity to each other, thereby providing an attenuated current path.
17. A method of making an electrical resistance element which comprises the steps of winding around the outer periphery of a cylindrical insulating former for a plurality of turns in close proximity to each other, a continuous length of a filament of a material selected from the group consisting of glass and glass-like materials having on its outer surface a firmly adherent, relatively thick, substantially uniform film consisting of metal selected from the group consisting of gold, platinum, and gold-platinum alloys, thereby providing an attenuated current path, and providing a stable resistance having a predetermined high constant value.
FRANK ENOCH KERRIDGE.
MICHAEL BELHAM.
GRAHAM PEARCE.
References Cited in the file of this patent UNITED STATES PATENTS Number
Claims (1)
1. A METHOD OF MAKING AN ELECTRICAL RESISTANCE ELEMENT WHICH COMPRISES THE STEPS OF APPLYING TO A GLASS FILAMENT A SOLUTION OF THE SULPHORESINATE OF AT LEAST ONE METAL SELECTED FROM THE GROUP CONSISTING OF GOLD AND PLATINUM DISSOLVED IN AN ESSENTIAL OIL SOLVENT MIXTUE, FIRING SAID COATED FILAMENT AT A TEMPERATURE SUFFICIENT TO BURN AWAY
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB1986/50A GB689461A (en) | 1950-01-25 | 1950-01-25 | Improvements in and relating to electrical resistors and resistance elements therefor |
Publications (1)
Publication Number | Publication Date |
---|---|
US2645701A true US2645701A (en) | 1953-07-14 |
Family
ID=9731570
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US225478A Expired - Lifetime US2645701A (en) | 1950-01-25 | 1951-05-10 | Electrical resistor and resistance elements therefor |
Country Status (3)
Country | Link |
---|---|
US (1) | US2645701A (en) |
GB (1) | GB689461A (en) |
NL (1) | NL83230C (en) |
Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2787560A (en) * | 1955-03-03 | 1957-04-02 | Stoddart Aircraft Radio Co Inc | Microwave resistor manufacture |
US2820727A (en) * | 1956-05-22 | 1958-01-21 | Gen Electric | Method of metallizing ceramic bodies |
US2930105A (en) * | 1953-07-31 | 1960-03-29 | Goodrich Co B F | Glass fiber material |
US2986090A (en) * | 1954-08-23 | 1961-05-30 | Ernst H Doerpinghaus | Electric fuses for igniting explosive charges |
US3085316A (en) * | 1959-03-26 | 1963-04-16 | Sage Electronics Corp | Method of making a resistor |
US3247020A (en) * | 1962-01-02 | 1966-04-19 | Owens Corning Fiberglass Corp | Electrically-conductive elements and their manufacture |
US3295090A (en) * | 1962-02-26 | 1966-12-27 | Dale Electronics | Electrical resistor having a core element with high heat dissipating properties |
US3371412A (en) * | 1966-02-11 | 1968-03-05 | Dale Electronics | Method of terminating a resistor |
US3491440A (en) * | 1967-06-12 | 1970-01-27 | Technology Instr Corp Of Calif | Method of making precision wire-wound electrical resistors |
US4506272A (en) * | 1981-11-06 | 1985-03-19 | Matsushita Electric Industrial Co., Ltd. | Thermal printing head |
US4523177A (en) * | 1984-01-16 | 1985-06-11 | Westinghouse Electric Corp. | Small diameter radiant tube heater |
US4572938A (en) * | 1984-01-16 | 1986-02-25 | Westinghouse Electric Corp. | Process for uniting sleeve members by brazing |
US4621182A (en) * | 1984-01-16 | 1986-11-04 | Westinghouse Electric Corp. | Small diameter radiant tube heater |
US5633035A (en) * | 1988-05-13 | 1997-05-27 | Fuji Xerox Co., Ltd. | Thin-film resistor and process for producing the same |
US20100288527A1 (en) * | 2006-06-12 | 2010-11-18 | Radim Lichy | Device for electric field control |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1081963B (en) * | 1956-07-30 | 1960-05-19 | S E C I Societa Electrotecnica | Electrical resistance surrounded by an insulating protective cover |
DE1188688B (en) * | 1962-01-20 | 1965-03-11 | Ibm Deutschland | Process for the production of printed circuits |
WO2015106426A1 (en) * | 2014-01-17 | 2015-07-23 | 李尚祐 | Surge-resistant wire-wound resistor and method for manufacturing same |
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US1832419A (en) * | 1925-05-28 | 1931-11-17 | Int Resistance Co | Electric resistance device |
GB486639A (en) * | 1937-09-10 | 1938-06-08 | Rosenthal Isolatoren Gmbh | An improved method of making high ohmic resistances with low temperature coefficient |
US2375178A (en) * | 1941-10-01 | 1945-05-01 | Ruben Samuel | Variable electrical resistor |
US2440691A (en) * | 1945-03-07 | 1948-05-04 | Continental Carbon Inc | Alloy metal film resistor |
GB611250A (en) * | 1946-04-09 | 1948-10-27 | Johnson Matthey Co Ltd | Improvements in and relating to electrical resistors |
US2487526A (en) * | 1947-04-14 | 1949-11-08 | Lockheed Aircraft Corp | Electric fire detector |
-
0
- NL NL83230D patent/NL83230C/xx active
-
1950
- 1950-01-25 GB GB1986/50A patent/GB689461A/en not_active Expired
-
1951
- 1951-05-10 US US225478A patent/US2645701A/en not_active Expired - Lifetime
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
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US1832419A (en) * | 1925-05-28 | 1931-11-17 | Int Resistance Co | Electric resistance device |
GB486639A (en) * | 1937-09-10 | 1938-06-08 | Rosenthal Isolatoren Gmbh | An improved method of making high ohmic resistances with low temperature coefficient |
US2375178A (en) * | 1941-10-01 | 1945-05-01 | Ruben Samuel | Variable electrical resistor |
US2440691A (en) * | 1945-03-07 | 1948-05-04 | Continental Carbon Inc | Alloy metal film resistor |
GB611250A (en) * | 1946-04-09 | 1948-10-27 | Johnson Matthey Co Ltd | Improvements in and relating to electrical resistors |
US2487526A (en) * | 1947-04-14 | 1949-11-08 | Lockheed Aircraft Corp | Electric fire detector |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2930105A (en) * | 1953-07-31 | 1960-03-29 | Goodrich Co B F | Glass fiber material |
US2986090A (en) * | 1954-08-23 | 1961-05-30 | Ernst H Doerpinghaus | Electric fuses for igniting explosive charges |
US2787560A (en) * | 1955-03-03 | 1957-04-02 | Stoddart Aircraft Radio Co Inc | Microwave resistor manufacture |
US2820727A (en) * | 1956-05-22 | 1958-01-21 | Gen Electric | Method of metallizing ceramic bodies |
US3085316A (en) * | 1959-03-26 | 1963-04-16 | Sage Electronics Corp | Method of making a resistor |
US3247020A (en) * | 1962-01-02 | 1966-04-19 | Owens Corning Fiberglass Corp | Electrically-conductive elements and their manufacture |
US3295090A (en) * | 1962-02-26 | 1966-12-27 | Dale Electronics | Electrical resistor having a core element with high heat dissipating properties |
US3371412A (en) * | 1966-02-11 | 1968-03-05 | Dale Electronics | Method of terminating a resistor |
US3491440A (en) * | 1967-06-12 | 1970-01-27 | Technology Instr Corp Of Calif | Method of making precision wire-wound electrical resistors |
US4506272A (en) * | 1981-11-06 | 1985-03-19 | Matsushita Electric Industrial Co., Ltd. | Thermal printing head |
US4523177A (en) * | 1984-01-16 | 1985-06-11 | Westinghouse Electric Corp. | Small diameter radiant tube heater |
US4572938A (en) * | 1984-01-16 | 1986-02-25 | Westinghouse Electric Corp. | Process for uniting sleeve members by brazing |
US4621182A (en) * | 1984-01-16 | 1986-11-04 | Westinghouse Electric Corp. | Small diameter radiant tube heater |
US5633035A (en) * | 1988-05-13 | 1997-05-27 | Fuji Xerox Co., Ltd. | Thin-film resistor and process for producing the same |
US20100288527A1 (en) * | 2006-06-12 | 2010-11-18 | Radim Lichy | Device for electric field control |
US8476526B2 (en) * | 2006-06-21 | 2013-07-02 | Abb Technology Ltd. | Device for electric field control |
Also Published As
Publication number | Publication date |
---|---|
NL83230C (en) | |
GB689461A (en) | 1953-03-25 |
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