US2915730A - Electrical resistor and method - Google Patents
Electrical resistor and method Download PDFInfo
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- US2915730A US2915730A US537810A US53781055A US2915730A US 2915730 A US2915730 A US 2915730A US 537810 A US537810 A US 537810A US 53781055 A US53781055 A US 53781055A US 2915730 A US2915730 A US 2915730A
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- 238000000034 method Methods 0.000 title description 18
- 229910044991 metal oxide Inorganic materials 0.000 claims description 38
- 150000004706 metal oxides Chemical class 0.000 claims description 38
- 239000000919 ceramic Substances 0.000 claims description 34
- 239000000203 mixture Substances 0.000 claims description 23
- 230000001464 adherent effect Effects 0.000 claims description 9
- 239000010408 film Substances 0.000 description 220
- 239000000463 material Substances 0.000 description 20
- 239000011521 glass Substances 0.000 description 17
- 239000000243 solution Substances 0.000 description 16
- 229910000410 antimony oxide Inorganic materials 0.000 description 12
- VTRUBDSFZJNXHI-UHFFFAOYSA-N oxoantimony Chemical compound [Sb]=O VTRUBDSFZJNXHI-UHFFFAOYSA-N 0.000 description 11
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 10
- 238000000576 coating method Methods 0.000 description 10
- 230000001681 protective effect Effects 0.000 description 10
- 239000011248 coating agent Substances 0.000 description 9
- 238000004519 manufacturing process Methods 0.000 description 9
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 description 9
- 229910001887 tin oxide Inorganic materials 0.000 description 9
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- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 4
- 229910001413 alkali metal ion Inorganic materials 0.000 description 4
- 239000002585 base Substances 0.000 description 4
- 150000001805 chlorine compounds Chemical class 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- 229910052718 tin Inorganic materials 0.000 description 4
- 239000012789 electroconductive film Substances 0.000 description 3
- 238000010304 firing Methods 0.000 description 3
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- 239000010409 thin film Substances 0.000 description 3
- HPGGPRDJHPYFRM-UHFFFAOYSA-J tin(iv) chloride Chemical compound Cl[Sn](Cl)(Cl)Cl HPGGPRDJHPYFRM-UHFFFAOYSA-J 0.000 description 3
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 2
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- FAPDDOBMIUGHIN-UHFFFAOYSA-K antimony trichloride Chemical compound Cl[Sb](Cl)Cl FAPDDOBMIUGHIN-UHFFFAOYSA-K 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 229910052793 cadmium Inorganic materials 0.000 description 2
- BDOSMKKIYDKNTQ-UHFFFAOYSA-N cadmium atom Chemical compound [Cd] BDOSMKKIYDKNTQ-UHFFFAOYSA-N 0.000 description 2
- 238000005524 ceramic coating Methods 0.000 description 2
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- 229910052738 indium Inorganic materials 0.000 description 2
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- 239000011701 zinc Substances 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 1
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- 229910052787 antimony Inorganic materials 0.000 description 1
- 229940075103 antimony Drugs 0.000 description 1
- WATWJIUSRGPENY-UHFFFAOYSA-N antimony atom Chemical compound [Sb] WATWJIUSRGPENY-UHFFFAOYSA-N 0.000 description 1
- 229910052797 bismuth Inorganic materials 0.000 description 1
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 description 1
- 150000003842 bromide salts Chemical class 0.000 description 1
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Images
Classifications
-
- 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
- H01C7/18—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 comprising a plurality of layers stacked between terminals
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B61—RAILWAYS
- B61G—COUPLINGS; DRAUGHT AND BUFFING APPLIANCES
- B61G9/00—Draw-gear
- B61G9/12—Continuous draw-gear combined with buffing appliances, e.g. incorporated in a centre sill
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C17/00—Surface treatment of glass, not in the form of fibres or filaments, by coating
- C03C17/22—Surface treatment of glass, not in the form of fibres or filaments, by coating with other inorganic material
- C03C17/23—Oxides
-
- 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
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
- H01B3/02—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of inorganic substances
- H01B3/08—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of inorganic substances quartz; glass; glass wool; slag wool; vitreous enamels
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
- H01B3/02—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of inorganic substances
- H01B3/08—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of inorganic substances quartz; glass; glass wool; slag wool; vitreous enamels
- H01B3/087—Chemical composition of glass
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01C—RESISTORS
- H01C1/00—Details
- H01C1/02—Housing; Enclosing; Embedding; Filling the housing or enclosure
- H01C1/032—Housing; Enclosing; Embedding; Filling the housing or enclosure plural layers surrounding the resistive element
-
- 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
-
- 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
- H01C7/006—Thin film resistors
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C2217/00—Coatings on glass
- C03C2217/20—Materials for coating a single layer on glass
- C03C2217/21—Oxides
- C03C2217/211—SnO2
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C2217/00—Coatings on glass
- C03C2217/20—Materials for coating a single layer on glass
- C03C2217/21—Oxides
- C03C2217/24—Doped oxides
- C03C2217/244—Doped oxides with Sb
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C2218/00—Methods for coating glass
- C03C2218/10—Deposition methods
- C03C2218/15—Deposition methods from the vapour phase
Definitions
- This invention relates to electrical resistors of the type comprising a ceramic body, such as a tube, rod or sheet of glass, porcelain, sillimanite, or the like, an adherent, electroconductive, metal oxide film on the surface of the body, and spaced, electroconductive terminals in electrical contact with the film.
- the ceramic body is heated to a temperature in the neighborhood of 500 700 C.
- the heated body is then contacted with the vapor or atomized solution of a selected hydrolyzable material to produce on the exposed ceramic surface a thin, strongly adherent, electroconductive film.
- Suitable materials and mixtures for producing such films include the chlorides, bromides, iodides, sulfates, nitrates, oxalates, and acetates of tin, indium, cadmium, tin and antimony, tin and indium, or tin and cadmium either with or without a similar hydrolyzable salt or other compound of a modifying metal such as zinc, iron, copper, or chromium.
- the film consists of the corresponding metal oxide or oxides.
- the thickness of the film increases with the length of time the heated body is contacted with the vapor or atomized solution, and its electrical resistance generally decreases as its thickness increases.
- Films having thicknesses from less than the first order of interference colors up to about the tenth order with electrical resistances of 1,000,000 or more down to 5 or less ohms per unit square can thus be produced. Resistances may also be adjusted upward by cutting through a film of a given resistance on a cylindrical ceramic body to shape the film into a spiral strip of predetermined width and length.
- Resistors comprising electroconductive films of this type provide distinct advantages over other types of re sistors for many purposes.
- metal oxide film resistors Prior to the present invention, however, it has not been feasible to produce commercially acceptable, metal oxide film resistors having aresistance over about 60 ohms/square. This undesirable situation has been due primarily to the general tendency of metal oxide films to have a high negative temperature coeflicient of resistance and to be quite unstable electrically, the latter being particularly-trouble some when the films are operated under, direct current load. This condition of instability manifests itself by a temporary or permanent change in resistance during operation of the resistor. While the tendency is ap parent at low temperatures, it becomes progressively aggravated as the temperature involved increases.
- the temperature coefiicient of a film or other form of resistance element is measured over a given temperature range.
- the particular temperature range selected will, of course, vary with different types of resistors and resistor applications, but will ordinarily correspond ap proximately to the expected operating range of the resistance element. It is known that electroconductive metal oxide films tend to have a negative temperature coefficient which is usually of greater magnitude in higher resistance compositions.
- the standard resistance of films in this composition range that is tin oxide films containing up to 6% antimony oxide, does not exceed about 60 ohms/square, however.
- standard resistance is meant the resistance in ohms/square of a film exhibiting a third order red inter ference color. It has been readily apparent then that, unless some practical means could be found to provide higher resistances on the order of 1004000 ohms/ square, the metal oxide film type resistor would be of limited significance.
- the film composition may be varied as, for example, increasing the anti mony oxide content of the present tin oxide films beyond the present 6% limit. This is of no avail, however, be cause as previously indicated, excessively high temperature coefficients are invariably associated with higher resistances produced in this manner.
- film composition is maintained constant but thinner films are formed on the base material, film resistance increasing as the thickness is decreased.
- This method may be carried out either by shortening the time of exposure or by diluting the film forming material.
- film compositions previously observed to produce low resistance films having acceptable temperature coefficients, can be used to form thinner, higher resistance films without substantially changing the nature of the temperature coefficient.
- compositions are deposited as very thin films, for example in thicknesses exhibiting only first order interference colors, to obtain resistance values on the order of 100 to 1000 ohms/square, such films are found to be highly unstable electrically, the degree of instability being such thatthe films are wholly un usable for resistor purposes. Thus, it would appear that the instability is a surface phenomenon which has its most pronounced effect on thin films.
- This ceramic coating was developed in conjunction with films having a third order or greater thickness and under such circumstances has proven highly satisfactory.
- a marked change in film resistance occurs which may be as detrimental to the film, from a resistance standpoint, as is the condition which the coating is designed to avoid.
- This effect may be a slight chemical interaction with, or physical disruption of, the metal oxide film during firing. With thicker films the effect is apparent but not especially serious. However, it produces such erratic effects on thinner films as to rule out its use completely.
- the improved electrical resistor resulting from such method and forming a part of this invention comprises a ceramic body, an adherent, electroconductive, metal oxide film on the surface of the body, a second electroconductive metal oxide film superimposed on the first film, and electrically conducting terminal members formed on the second film and in electrical contact with the first film.
- the secondary or protective film may contain oxides differing from those in the primary film, or the two films may contain the same oxides in different proportions.
- the protecting film must have a sufiiciently higher resistance than the primary film so that a major proportion of longitudinal electrical current flow in the resistor preferentially occurs in the protected or primary film.
- the protecting coating must possess sufficient conductivity to permit establishment of electrical contact between the terminals and the primary conducting film by a transverse flow of current through the protective film.
- the single figure in the accompanying drawing illustrates one embodiment of the present invention and shows partly in section an electrical resistor composed of a cylindrical ceramic body provided with two superimposed electroconductive metal oxide films and spaced terminal members.
- ceramic body is heated to a temperature of about 450 C. or higher, but not above its softening or deformation point, and preferably to a temperature of about 600-650 C.
- Ceramic body 10 while shown as solid, may also be a hollow body and is preferably a length of glass tubing or cane.
- the heated body is then contacted by vapors from, or an atomized solution of, a selected metal salt or salts to produce electroconductive film 11. Subsequent to formation of this initial coating and preferably while the ceramic body is still within the elevated temperature range at which film formation occurs, it is contacted with a second film forming material to produce a protective film 12.
- each film may be anhydrous and fumed onto the body or may be dissolved in compatible organic solvents and applied in solution form. It is usually more convenient, however, to employ an aqueous solution of the salt or salts with sulficient acid in the solution to prevent separation of hydrolysis products. This aqueous solution may then be sprayed on the surface of the heated ceramic body to produce the desired film, or may be thermally converted into a hot vapor phase to which the ceramic body is exposed. Exposure of the ceramic body to the film forming material, in each instance, is continued until. a film having the desired thickness, and consequently the desired resistance, is formed from the contacting material.
- the materials used in producing each film contain the same components, although necessarily in different proportions. correspondingly then the films will contain the same oxides although indifferent proportions to provide the required higher resistance in the protective cover film.
- the primary or conducting film which customarily contains up to about 6% antimony oxide, may be produced from a suitable mix ture of SnC1 -5H O and SbCl.
- a solution containing 99 parts of the tin chloride to 1 part of the antimony chloride, with water and concentrated or 37% hydrochloric acid in a ratio of 5/1 as solvent has been found particularly suitable because of the positive temperature coefficient of resistance in the resulting film. It is necessary, however, that a film of this composition be very thin, e.g. about a first order film having reference to interfer ence colors as a measure of thickness, where higher resistances on the order of 500 ohms/square are desired.
- the protective film must, of course, have a considerably higher content of antimony oxide to provide the desired higher resistance and preferably is formed from an acid solution containing about 30-60 parts antimony chloride and -40 parts tin chloride with the relative oxide contents in the film roughly corresponding to these ranges also.
- tin oxide films may be poisoned, that is given a much higher resistance, by incorporating minor amounts of such oxides as those of bismuth, iron, chromium and zinc, and rendered quite satisfactory for cover films.
- suitable compositions for forming cover films are shown in the table below along with the resistance in ohms/ square of an oxide film formed from the composition and having a third order red thickness in terms of interference colors.
- compositions are used in solution form.
- the solution is made by dissolving one gram of the tin chloride in a 1 to 5 mixture of concentrated hydrochloric acid and H 0 to produce 1 ml. of solution; one gram of SbCl (when used) in a 1 to 1 mixture of concentrated hydrochloric acid and H 0 to make 1 ml. of solution; mixing these solutions in indicated proportions; adding other chlorides (in grams) and phenol (in mls.) as required.
- top or cover film The essential function of the top or cover film is to insulate the primary film from'atmospheric and other deleterious external influences. It must then be sufficiently thick to provide such insulation and in general cover films should be at least third order films.
- terminals 13 are applied over film 12. They are desirably of a metallic nature and applied as a thin band at either end of the resistor. In forming such terminals any well-known metallizing procedure may be employed. For example, a thin coating of organo-metal material such as the noble metalresinates may be fired. on the filmed body. Alternatively, metallizing pastes containing a vitreous flux, such as commercially available silver pastes, may be used.
- terminals 13 take the form of thin, metallic bands encircling the end of the resistor, as shown, and an eighth to a quarter inch in width. This not only provides a large surface on which to fasten leads, terminal caps or the like, but also furnishes a larger contact area on the upper or cover film.
- the ratio of the resistance of the top film to that of the under or primary conducting film is too small, a substantial part of the longitudinal current flow will be shunted through it. In other words, with respect to longitudinal current flow the two films then function as parallel resistances. To the extent that the top fllrn carries any longitudinal flow of current, it functions as an exposed conducting film rather than a protecting film. In general, high resistance films of the type used for cover films have very. poor electrical stability as well as relatively high negative temperature coeflicients of resistance.
- the resistance of the protecting film be sufficiently high so that the resistance of the primary conducting coating alone istsubstantially the same, that is within 1% or so, of the final composite multi-coat film.
- Metal oxide films suitable for use as' the primary con-- ducting element in a resistor may vary in resistance from about 20 to 10,000 ohms/square.
- a cover or protecting film should have a resistance at least ten times that of the conducting film in conjunction with which it is used.
- cover films should have a resistance from at least 200 ohms up to about 10 megohms/ square.
- the improved dual-coated resistors it is convenient to pass a continuous length of heated glass or other ceramic tube or cane past a suitable fuming or spray apparatus.
- Glass is particularly convenient to use since it has been found that glass cane or tubing, as drawn from the melting chamber, may be maintained at a sufficiently high temperature to enable continuous film formation on the surface without reheating.
- Two substantially similar devices for projecting the film forming materials onto the glass surface may be set up in succession with the spray or fume pattern and length of exposure in each instance correlated with drawing speed of the glass so that a proper thickness of each film is achieved. Following that, terminals 13 may be applied in the usual manner over the cover film.
- Base 10 is also preferably substantially free of alkali metal ions for optimum electrical stability. It is known that alkali metal ions can migrate in vitreous or glassy media. As explained in my co-pending application filed of even date herewith, this condition appears to exert a serious and erratic influence on the electrical properties of electroconductive metal oxide films and to have been a major contributing factor in their electrical instability. By substantially free is meant free from any but trace impurities.
- Cane 0.260 inch in diameter, was drawn in conventional manner from an alkali-free glass having the following compositions: 58% SiO 15% A1 0 10% CaO, 7% MgO, 6% BaO and 4% B 0 During the drawing process and while the glass cane was still at an elevated temperature, it was successively passed through two adjacent coating chambers. In the first chamber the cane was exposed to the hot vapors of a hydrochloric acid solution of mixed chlorides containing 97.5 parts SnCl -5H O and 2.5 parts SbCl This produced on the cane a first order white, metal oxide film having a resistance of about 600 ohms/square. The resistance varied somewhat depending on the glass temperature and the rate of draw and hence the length of exposure.
- the solution concentration may be varied, a dilute solution producing a thinner film in a given time.
- the coated cane was exposed to the hot vapors of a hydrochloric acid solution of mixed chlorides containing 40 parts SnCl -5H O and 60 parts SbCl This produced a sixth order film having a resistance of 50,000 ohms/square.
- the cane was cut up in short lengths and metal handed to produce resistor elements. These resistors were then subjected to various tests. It was observed that the temperature coefficient of the unit was negative in sign and, when measured between 37 and 97 C., was from 200400 parts per million/degree C. The variations were primarily due to changes in the unstable cover film during metallizing but well-within a specified limit of 500 ppm.
- the resistors of the present invention provide the desired combination of high resistance values, low temperature coefficient, and satisfactory stability under electrical load.
- An electrical resistor comprising a ceramic body, an adherent, electroconductive, metal oxide film on the surface of the ceramic body, a second electroconductive metal oxide film superimposed on the first film, the second film having a different composition from and a higher resistance than the first film, and spaced, electrically conducting terminal members in physical contact with said second film and spaced from said first film by said second film, but in electrical contact with said first film through said second film.
- the electrical resistor of claim 4 in which the first film is composed of tin oxide and up to about 6% antimony oxide.
- An electrical resistor comprising a ceramic body, an adherent, electroconductive, metal oxide film on the surface of the ceramic body, a second electroconductive metal oxide film superimposed on the first film and spaced, electrically conducting terminal members in physical contact with the second film and spaced from said first film by said second film, but in electrical contact with said first film through said second film, the electrical resistivity of the second film being such that under electrical load no significant impedance is offered to a transverse fiow of current through those portions of the second film between the terminals and the first film, but
- a method of making an electrical resistor which comprises exposing a heated ceramic body to a film forming material to form an adherent, electroconductive metal oxide film on its surface, thereafter exposing the filmed ceramic body to a second film forming material to superimpose on the first film a second electroconductive metal oxide film which is of such composition and thickness relative to the first that no significant impedance is offered to a transverse fiow of electrical current while no substantial longitudinal current flow occurs in the second film, and thereafter applying metallic terminals over the second film in such manner that they are spaced from said first film by said second film, but in electrical contact with said first film through said second film.
- a method of making an electrical resistor which comprises successively exposing a heated ceramic body to two different film-forming materials whereby two separate, electroconductive, metal oxide films are formed in superimposed relationship on the surface of the body with the second film having a higher resistance than the first film, and then applying electroconductive terminals over the second film and spaced from said first film by said second film, but in electrical contact with the first film through the second film.
- a method of making an electrical resistor which comprises heating a ceramic body to a temperature of at least 450 C., exposing the heated body to a material capable of forming on the surface of the body an electroconductive metal oxide film, continuing such exposure until the resistance of such film reaches a predetermined value within the range 2010.000 ohms per square, thereafter exposing the heated body to a second material capable of forming an electroconductive metal oxide film having a different composition and a higher resistance than the first film, continuing such exposure until a film having a selected resistance at least ten times that of the first film and within the range of 200 ohms to 10 megohms per square is produced, and then applying electroconductive terminals on said second film.
- a method in accordance with claim 8 in which the first film forming material to which the ceramic body is exposed is capable of producing a tin oxide film containing up to 6% antimony oxide.
- the method of making electrical resistors in which the current carrying element is an electroconductive metal oxide film deposited on the surface of a ceramic body which comprises drawing an elongated glass body from a molten glass reservoir, successively contacting the glass body while at a temperature in excess of 450 C. with two difierent film-forming materials whereby two separate, electroconductive, metal oxide films are formed in superimposed relationship on the surface of the glass with the second film having a higher resistance than the first film, separating the filmed glass body into appropriate lengths and applying spaced electroconductive terminals to the surface of the second film on each length in such manner that the terminals are physically spaced from the first film, but in electrical contact therewith through the second film.
- composition of the first film-forming material with which the glass body is contacted is such as to produce a film containing tin oxide and antimony oxide, the latter being present in amounts up to 6%, and the contact time with this film-forming material is such that the film produced has a thickness less than third order red and a resistance of over 60 ohms per square.
- An electrical resistor comprising a ceramic body, an adherent, electroconductive, metal oxide film on the surface of the ceramic body, such metal oxide film having a resistance of over 60 ohms per square, a thickness less than third order red and being composed of tin oxide and up to 6% antimony oxide, a second electroconductive metal oxide film superimposed on the first film, the second film having a different composition from and a higher resistance than the first film but physically separated therefrom by said second film, and spaced, electrically conducting terminal members formed on said second film and in electrical contact with said first film.
- an improved method which comprises forming successively and in superimposed relationship tWo electroconductive metal oxide films and electroconductive terminals, the terminals being physically spaced from the initial film but in electrical contact therewith through the second film.
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- Engineering & Computer Science (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Inorganic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Life Sciences & Earth Sciences (AREA)
- Mechanical Engineering (AREA)
- General Chemical & Material Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Non-Adjustable Resistors (AREA)
- Apparatuses And Processes For Manufacturing Resistors (AREA)
- Springs (AREA)
- Adjustable Resistors (AREA)
Priority Applications (9)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DENDAT1066654D DE1066654B (zh) | 1955-09-30 | ||
US537810A US2915730A (en) | 1955-09-30 | 1955-09-30 | Electrical resistor and method |
GB29287/56A GB806189A (en) | 1955-09-30 | 1956-09-25 | Electrical resistor and method |
FR1159853D FR1159853A (fr) | 1955-09-30 | 1956-09-27 | Résistance électrique et son procédé de fabrication |
FR1159854D FR1159854A (fr) | 1955-09-30 | 1956-09-27 | Résistance électrique |
CH343492D CH343492A (fr) | 1955-09-30 | 1956-09-28 | Résistance électrique |
CH341885D CH341885A (fr) | 1955-09-30 | 1956-09-28 | Résistance électrique et procédé pour sa fabrication |
BE551424D BE551424A (zh) | 1955-09-30 | 1956-09-29 | |
GB18378/57A GB809190A (en) | 1955-09-30 | 1957-06-11 | Draft gear for railroad cars |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US537810A US2915730A (en) | 1955-09-30 | 1955-09-30 | Electrical resistor and method |
Publications (1)
Publication Number | Publication Date |
---|---|
US2915730A true US2915730A (en) | 1959-12-01 |
Family
ID=24144194
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US537810A Expired - Lifetime US2915730A (en) | 1955-09-30 | 1955-09-30 | Electrical resistor and method |
Country Status (6)
Country | Link |
---|---|
US (1) | US2915730A (zh) |
BE (1) | BE551424A (zh) |
CH (2) | CH343492A (zh) |
DE (1) | DE1066654B (zh) |
FR (2) | FR1159853A (zh) |
GB (2) | GB806189A (zh) |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3217281A (en) * | 1962-05-28 | 1965-11-09 | Corning Glass Works | Electrical resistor |
US3411934A (en) * | 1963-12-23 | 1968-11-19 | Ppg Industries Inc | Method of producing tin oxide-cobalt oxide plural layers on glass articles |
US3437974A (en) * | 1966-12-09 | 1969-04-08 | Corning Glass Works | High strength resistor |
JPS4929839A (zh) * | 1972-07-14 | 1974-03-16 | ||
JPS4929841A (zh) * | 1972-07-14 | 1974-03-16 | ||
US3982218A (en) * | 1974-09-19 | 1976-09-21 | Corning Glass Works | Temperature sensing device and method |
US3983290A (en) * | 1974-09-03 | 1976-09-28 | Stauffer Chemical Company | Fire retardant polyvinyl chloride containing compositions |
US5889459A (en) * | 1995-03-28 | 1999-03-30 | Matsushita Electric Industrial Co., Ltd. | Metal oxide film resistor |
US20060251930A1 (en) * | 2005-05-04 | 2006-11-09 | Samsung Sdi Co., Ltd. | Rechargeable battery |
US20150364286A1 (en) * | 2014-06-13 | 2015-12-17 | Smart Electronics Inc. | Complex protection device |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1186539B (de) * | 1960-09-07 | 1965-02-04 | Erie Resistor Ltd | Elektrischer Widerstand mit einer Widerstandsschicht aus Metalloxyd oder Metall und Verfahren zu seiner Herstellung |
US3857174A (en) * | 1973-09-27 | 1974-12-31 | Gen Electric | Method of making varistor with passivating coating |
JPS5480547A (en) * | 1977-12-09 | 1979-06-27 | Matsushita Electric Ind Co Ltd | Ceramic varister |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1771236A (en) * | 1926-10-06 | 1930-07-22 | Chicago Telephone Supply Co | Resistance strip |
US2564706A (en) * | 1946-05-02 | 1951-08-21 | Corning Glass Works | Coated resistance |
US2564707A (en) * | 1947-09-03 | 1951-08-21 | Corning Glass Works | Electrically conducting coatings on glass and other ceramic bodies |
US2564677A (en) * | 1947-09-15 | 1951-08-21 | Corning Glass Works | Electrically conducting coating on glass and other ceramic bodies |
US2647068A (en) * | 1948-03-16 | 1953-07-28 | Bishop H Russell | Process of treating vitreous materials |
US2648754A (en) * | 1947-07-22 | 1953-08-11 | Pittsburgh Plate Glass Co | Electroconductive article |
US2798140A (en) * | 1953-04-06 | 1957-07-02 | Wilbur M Kohring | Resistance coatings |
-
0
- DE DENDAT1066654D patent/DE1066654B/de active Pending
-
1955
- 1955-09-30 US US537810A patent/US2915730A/en not_active Expired - Lifetime
-
1956
- 1956-09-25 GB GB29287/56A patent/GB806189A/en not_active Expired
- 1956-09-27 FR FR1159853D patent/FR1159853A/fr not_active Expired
- 1956-09-27 FR FR1159854D patent/FR1159854A/fr not_active Expired
- 1956-09-28 CH CH343492D patent/CH343492A/fr unknown
- 1956-09-28 CH CH341885D patent/CH341885A/fr unknown
- 1956-09-29 BE BE551424D patent/BE551424A/xx unknown
-
1957
- 1957-06-11 GB GB18378/57A patent/GB809190A/en not_active Expired
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1771236A (en) * | 1926-10-06 | 1930-07-22 | Chicago Telephone Supply Co | Resistance strip |
US2564706A (en) * | 1946-05-02 | 1951-08-21 | Corning Glass Works | Coated resistance |
US2648754A (en) * | 1947-07-22 | 1953-08-11 | Pittsburgh Plate Glass Co | Electroconductive article |
US2564707A (en) * | 1947-09-03 | 1951-08-21 | Corning Glass Works | Electrically conducting coatings on glass and other ceramic bodies |
US2564677A (en) * | 1947-09-15 | 1951-08-21 | Corning Glass Works | Electrically conducting coating on glass and other ceramic bodies |
US2647068A (en) * | 1948-03-16 | 1953-07-28 | Bishop H Russell | Process of treating vitreous materials |
US2798140A (en) * | 1953-04-06 | 1957-07-02 | Wilbur M Kohring | Resistance coatings |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3217281A (en) * | 1962-05-28 | 1965-11-09 | Corning Glass Works | Electrical resistor |
US3411934A (en) * | 1963-12-23 | 1968-11-19 | Ppg Industries Inc | Method of producing tin oxide-cobalt oxide plural layers on glass articles |
US3437974A (en) * | 1966-12-09 | 1969-04-08 | Corning Glass Works | High strength resistor |
JPS4929839A (zh) * | 1972-07-14 | 1974-03-16 | ||
JPS4929841A (zh) * | 1972-07-14 | 1974-03-16 | ||
US3983290A (en) * | 1974-09-03 | 1976-09-28 | Stauffer Chemical Company | Fire retardant polyvinyl chloride containing compositions |
US3982218A (en) * | 1974-09-19 | 1976-09-21 | Corning Glass Works | Temperature sensing device and method |
US5889459A (en) * | 1995-03-28 | 1999-03-30 | Matsushita Electric Industrial Co., Ltd. | Metal oxide film resistor |
US20060251930A1 (en) * | 2005-05-04 | 2006-11-09 | Samsung Sdi Co., Ltd. | Rechargeable battery |
US8709621B2 (en) * | 2005-05-04 | 2014-04-29 | Samsung Sdi., Ltd. | Rechargeable battery |
US20150364286A1 (en) * | 2014-06-13 | 2015-12-17 | Smart Electronics Inc. | Complex protection device |
CN105206479A (zh) * | 2014-06-13 | 2015-12-30 | 斯玛特电子公司 | 复合保护元件 |
Also Published As
Publication number | Publication date |
---|---|
CH343492A (fr) | 1959-12-31 |
CH341885A (fr) | 1959-10-31 |
DE1066654B (zh) | 1959-10-08 |
BE551424A (zh) | 1959-12-18 |
GB806189A (en) | 1958-12-23 |
GB809190A (en) | 1959-02-18 |
FR1159853A (fr) | 1958-07-03 |
FR1159854A (fr) | 1958-07-03 |
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