SE129100C1

SE129100C1 -

Info

Publication number: SE129100C1
Authority: SE
Publication date: 1950-01-01

Description

Uppfinnare: W. Lehfeld och H. Lueder. Inventors: W. Lehfeld and H. Lueder.

Prioritet begard Ira den 18 december 1937 och den, mars 1938 (Tyska riket). Priority was given to Ira on December 18, 1937 and March 1938 (German Empire).

Elektriska motstand liava, till och med om tillverkningen ager rum med samma utgangsmaterial under samma betingelser, alltid nagot fran det avsedda vardet avvikande slutvarden. For att erhalla sa exakta varden SOM mojligt och halal spridningstoleransen liten, hava mycket olika vagar fOreslagits, vilka principiellt best a i att utjamna del fardiga motstandet under kontroll av en rnatanordning eller underkasta detsamma en kontroll me-deist matanordningen, foretradesvis under det sista tillverkningssteget. Sasom medel for utjamningen resp. aven for det sista tillverkningssteget utfores sasom bekant ofta en borttagning av aktivt motstandsmaterial, exempelvis darigenom, att man vid tradmotstand utfOr dessa med plustolerans och med anvandning av en rnatanordning avlindar sa mycket trad, att det avsedda vardet uppnas. Vid skiktmotstand, d. v. s. motstand, vilka besta. av ett tunt motstandsskikt pa en barkropp, avlagsnar man pa kant satt, exempelvis genom utstansning, tillsammans med delar av barkroppen eller genom bortskrapning eller avslipning delar av motstandsskiktet for att minska tvarsektionen eller Oka ledningsvagen. Vid massamotstand, vilka besta av en blandning av ledare- och halvledarepartiklar, är det visserligen aven majligt att genom avlagsnande av motstandsmaterial forandra motstandsvardet, men detta utgor icke nagon lamplig atgard, eftersom motstandets rymddimensioner harigenom andras. Av detta skal anvander man sasom bekant vid massamotstand delvis en termisk efterbehandling eller efterat anbragt tryck fOr att paverka motstandsvardet. Electrical resistance liava, even if the manufacture takes place with the same starting material under the same conditions, always slightly deviates from the intended value. In order to obtain as precise a value as possible and the halal spreading tolerance is small, very different scales have been proposed, which in principle consist of leveling the finished resistance under the control of a feeding device or subjecting it to a control with the feeding device, preferably during the last manufacturing step. As a means of equalization resp. even for the last manufacturing step, as is well known, a removal of active resistance material is often carried out, for example by performing so much wire in the case of thread resistance and using a wire device to unwind so much thread that the intended value is achieved. In the case of layer resistance, i.e. resistance, which exist. of a thin resistance layer on a support body, one is removed at the edge set, for example by punching, together with parts of the support body or by scraping or sanding parts of the resistance layer to reduce the cross section or increase the conduit. In the case of mass resistors, which consist of a mixture of conductor and semiconductor particles, it is admittedly also possible to change the resistance value by removing resistive material, but this does not constitute an appropriate measure, since the space dimensions of the resistor thereby change. Of this shell, as is known in the case of mass resistance, a thermal after-treatment or after applied pressure is partly used to influence the resistance value.

Dessa forslag erfordra dock relativt lang tid och stora kostnader och mojliggora endast erhallandet av i genomsnitt nagorlunda anvandbara motstandsmedelvarden. However, these proposals require a relatively long time and large costs and only make it possible to obtain on average reasonably usable resistance averages.

Det är Liven redan kant att pa motstandet anbringa bra ledande skikt, vilka delvis kortsluta motstandskroppen och darigenom lika ledes astadkomma en inverkan pa motstandsvardet. Liven is already on the verge of applying good conductive layers to the resistor, which in part short-circuit the resistor body and thereby in the same way have an effect on the resistance value.

Vid motstanden enligt uppfinningen Or det nu fraga oni de kanda massamotstand, vilka i huvudsak besta av metallforeningar, foretradesvis metalloxider, och vilka framstallas genom branning. Vid sadana motstand, vilka Oro kanda sasom motstand med negativ temperaturkoefficient resp. s. Ic. varmeledare, Oro nu bra ledande belaggningar Over huvud taget endast anvandbara, da de Oro inbranda, sOsorn Or i och for sig Taint for framstallning av stromanslutningsstallen vid motstand. Om marl nu pa det kanda sattet vid de foreliggande motstanden inbranner bra ledande skikt i avsikt att utnyttja dessa for utjamning av motstandsvardet, kan man icke uppna en utjamning darigenom, att man, sasom foreslagits vid andra paforda skikt, okar belaggningen, tills motstandets avsedda vorde ãr uppnail, eftersom motstanden andras till sitt motstandsvarde icke endast genom det bra ledande skiktet utan aven for varje gang genom den termiska pakanningen vid inbranningen av det bra ledande skiktet. In the case of the resistor according to the invention, there are now known pulp resistors which consist mainly of metal compounds, preferably metal oxides, and which are produced by firing. At such resistances, which Oro kanda as resistance with negative temperature coefficient resp. s. Ic. heat conductors, Oro now good conductive coatings In general only usable, as they Oro burn in, sOsorn Or in and of itself Taint for manufacturing the power connection stall in the event of resistance. If marl now in the known manner in the present resistance burns in good conductive layers with the intention of using these for equalization of the resistance value, one can not achieve an equalization in that, as has been proposed with other proposed layers, the coating increases, until the resistance is intended is oppnail, since the resistance changes to its resistance value not only through the good conductive layer but also for each time through the thermal packing during the firing of the good conductive layer.

Enligt uppfinningen inbrannas darfor de pa motstandet inbranda bra ledande skikten, fiiretradesvis metallskikt, tvartom till sadan storlek, att motstandsvardet ligger under det avsedda vOrdet. Darefter minskas dessa skikt, t. ex. genom avslipning, till sina geometriska dimensioner, tills det avsedda vardet Or uppnatt. According to the invention, therefore, the good conductive layers burned in on the resistor, preferably metal layers, are burned in, on the contrary to such a size that the resistance value is below the intended value. Thereafter, these layers are reduced, e.g. by grinding, to its geometric dimensions, until the intended value Or is reached.

Genom den enda branningsprocessen med medvetet med avseende pa ytan alltfor stora inbranda kortslutande skikt och den i anslutning dartill foljande, utan uppviirmning forsiggitende minskningen av dessa skikt kan alltsa vid det till grund for uppfinningen liggande fiirfarandet pa enkelt satt en noggrann utjamning av motstandsvardet genomforas. Minskningen av skikten kan ernas genom bortskrapning, bortslipning eller dylikt. Motstandets tvarsektion eller ovriga givna dimen- 2— — sioner hos del egentliga motstandet andras alltsa icke, titan motstandsvardet pitverkas riktning mot mindre varden uteslutande genom inverkan av den battre ledande, med en del av motstandet i beroring stilende massan. Through the only burning process with deliberately too large burn-in short-circuiting layers on the surface and the subsequent, without heating precautionary reduction of these layers, an accurate equalization of the resistance value can easily be carried out in the process underlying the invention. The reduction of the layers can be achieved by scraping, sanding or the like. The transverse section of the resistor or other given dimensions of the actual resistor do not differ from each other, the titanium resistor guard is directed towards the smaller guard exclusively by the influence of the better conductor, with part of the resistor touching the mass.

VW en sarskilt lämplig utfOringsform utnyttjas pa i och for sig kant satt de for stromtillforingen erforderliga kontakterna samtidigt sasom utjamningsskikt, for vilket andamal kontaktdelarna anbringas storre On som Or i och for sig nodvandigt, sit att genom deras minskning en utjamning av motstandsviirdet mopiggores. VW a particularly suitable embodiment is used on the per se edge, the contacts required for the power supply at the same time as an equalization layer, for which the contact parts are applied larger than Or per se necessary, so that by their reduction an equalization of the resistance value is mopiggores.

Anbringandet av utjamningsytan kan utom enligt de kinda forfarandena, sitsom kemisk forsilvring, paangning i hogyakuum eller katodforstoftning, exempelvis utforas genom anbringande ay kolloidalt silversalt i ett losningsmedel och reduktion genom termisk be-handling, eller ocksit kunna silverskikt framstallas genom anbringande av silveroxidpulver, blandat med ett flussmedel, och reduk- lionsamtidig inbranning. Dessa skikt kunna Oven under framstallningen hopsvetsas med stela metallkontakter. The application of the leveling surface can, except according to the kind procedures, such as chemical silvering, hogy vacuum or cathode sputtering, be carried out, for example, by applying a colloidal silver salt in a solvent and reduction by thermal treatment, or a flux, and simultaneous reduction of combustion. These layers can also be welded together with rigid metal contacts during manufacture.

Del angivna forfaringssattet Or sarskilt viktigt for framstallning av motstand med 'legally temperaturkoefficient, yilka besta av en blandning av halvledare, siirskil I metalloxider, vartill kopparoxid, uranoxid och dylikt lampa sig. Om man forfardigar dessa mot-stand i form av stavar och anordnar metallkontakterna for stromtillforingen i sam ma plan, har man i forsta hand den fordelen, att anslutningsandarna ligga precis mitt emot varandra. GC110111 anordnandet av ett ytteriigare skikt pa' den sida av kroppen, sum Or motsatt den, paanslutningskontakter- na ligga, exempelvis 'rid rektangulara stavar pa det salt, som visas i fig. 1 och 2 pa hifogade ritning, ernar man pa i °eh for sig kant satt, alt faltlinjerna overviigande passera genom sjalva kroppen och icke Iiings ytan. 115rigenom uppstar en janm stromf5rdelning, sit alt nagra lokala uppviirmningar och clamed nagra viirmegenomslag icke kunna uppstti. Harmed Or motstandet, da utjamningen utfö- res efter den termiska aldringen, fullt fardigt, sO alt nagra nya kontaktstallen icke bildas, villta maste underkastas en ytterligare Old-ring, varigenom itnyo motstandsandringar skulle kunna intraffa. Part of the process described above is particularly important for the production of resistors with a legal temperature coefficient, which consists of a mixture of semiconductors, especially in metal oxides, to which copper oxide, uranium oxide and the like lamp. If these resistors are manufactured in the form of rods and the metal contacts for the power supply are arranged in the same plane, the advantage has in the first place that the connecting spirits lie exactly opposite each other. GC110111 The arrangement of an additional layer on the side of the body, the opposite of which, the connecting contacts lie, for example, riding rectangular rods on the salt shown in Figures 1 and 2 of the accompanying drawing, are shown in Figs. for the edge sat, all the fold lines predominantly pass through the body itself and not the surface of the body. As a result, an even distribution of electricity arises, and some local heaters and clams cannot withstand any heat transfer. If the resistance, when the equalization is carried out after the thermal aging, is fully completed, so that no new contact numbers are formed, the wild must be subjected to a further Old-ring, whereby new changes of resistance could occur.

I fig. 1 p0 ritningen visas sasom exempel tvarsektionen av en motstandsstav, som Or atergiven i sidovy i fig. 2. Harvid betecknar a motstandskroppen av motstandsmaterial, b. c stromtillforingskontakterna och d ett metallskikt, som Or anordnat pa den fran stromtillforingskontakterna vanda sidan. Utjamningen till motstandets avsedda varde fOretages genom minskning av metallpalaggen h, coch d, och rnotstandet visar sedan exempelvis utseendet enligt fig. 3. Fig. 1 of the drawing shows, by way of example, the cross-section of a resistor rod, which is shown in side view in Fig. 2. Here denotes the resistor body of resistor material, b. The current supply contacts and d a metal layer, which Or arranged on the side of the current supply contacts. The equalization to the intended value of the resistor is effected by reducing the metal pallets h, coch d, and the rnotstand then shows, for example, the appearance according to Fig. 3.

Claims

Patent claim:

1. Explanatory method for equalizing the resistance surfaces of metal compounds, preferably metal oxides, preferably metal oxides, horse-drawn, mass-produced mass resistors, so-called protective conductors, which are provided with burnt, short-circuiting layers, can be characterized by the fact that burn in on the resistor to its size, the center of resistance lies at the intended yard, and that these layers, for example genuine sanding, are reduced to their surface, all the parts of the resistance shorted by the layers become smaller, until the intended resistance value Or is reached.

A method according to claim 1, characterized in that the contact layers serving as stripping connections are used or co-used for the leveling,

Procedure according to claim 1, it can be claimed that the reduction of the good conductive layers is not effected until after a thermal aging of the resistor.

4. A method according to the patent claim can be characterized in that, in the middle of the leveling except for the current connections serving, in a plane arranged contact layers, a further good conductive layer applied to the side of the resistance body arranged from the contacts is used. 4t, 4,21,13,1111 I 9:; 11 Kintgl. Polar. P. 1_ Norsteilt & -. 85ner 5000S9