Xyoo 1859, Mr. Simpson tau tsim lub ntiaj teb thawj lub tshuab rhaub hluav taws xob thiab tau txais patent rau cov khoom no. Cov hluav taws xob cua sov hluav taws xob yog tsim los ntawm cov hlau hlau coil uas yog armored nyob rau hauv ib tug hlau raj, thiab cov hlau raj thiab hlau hlau yog insulated nrog ceramic insulating cov ntaub ntawv los ua ib tug cua sov lub cev, uas yog peb lub npe hu ua hluav taws xob rhaub.
Vim tias tsis muaj qee yam khoom siv thaum lub sijhawm ntawd, qhov kev tsim no tsis tuaj yeem siv tau, thiab tsis muaj cov xaim hlau uas tsim nyog raws li cov khoom siv cua sov, thiab cov khoom siv uas siv tau tsuas yog hlau hlau xwb. Txawm li cas los xij, raws li qhov kev tiv thaiv ntawm cov hlau hlau me me, nws yog qhov nyuaj rau kev ua kom muaj hluav taws xob siab thiab cov hlau tsis kam ua los ntawm cov hlau muaj txiaj ntsig yog kim.
Kev tsim thiab kev loj hlob ntawm cov khoom cua sov tsis tau pib nce mus txog 1910, thaum lub tebchaws United States twb tau tsim cov nickel-chromium alloy, uas muaj kub tsis kam thiab siab resistivity, thiab cov khoom siv hluav taws xob inorganic rwb thaiv tsev twb muaj lawm. Txij thaum ntawd los, cov xwm txheej yooj yim rau kev tsim hluav taws xob rhaub hluav taws xob tau ua tiav.
Txoj kev loj hlob tiag tiag ntawm lub tshuab rhaub hluav taws xob yog thaum Tsov Rog Thoob Ntiaj Teb thib 1, thaum cov txheej txheem tseem ceeb tau tsim los ntawm cov txheej txheem hmoov, thiab xyoo 1918, Tebchaws Asmeskas General Electric Company tau muab patent rau kev tsim khoom (Generalelectric of USA), uas yog tsim los ntawm cov raj hlau. Nyob rau hauv lub raj yog concentric txoj hauj lwm ntawm lub cua sov hlau kauv lub voj voog, ib ncig yog hmoov rwb thaiv tsev khoom.
Tab sis txoj hauv kev no tsis ua haujlwm, vim tias tsis muaj cov tshuab tsim nyog lossis kev tsim khoom. Kom txog rau thaum nruab nrab-fifties nyob rau hauv cov teb chaws Europe, txoj kev siv yog tseem complex, ua rau cov nqi kim, thiab tsuas yog tom qab (Bulten Kanthal) nce qib ntawm lub tebchaws United States (OAKLEY) tus thawj tsim ntawm lub tshuab tsim rau lub American lag luam, lub daim ntawv thov thiab muaj koob meej ntawm nws cov khoom siv hluav taws xob cua sov tau nce thoob plaws ntiaj teb.
