Thaum twg yog cov hlau saw invented
Cov hlau pom, tshwj xeeb tshaj yog nyob rau hauv nws cov niaj hnub daim ntawv raws li lub pob zeb diamond hlau pom, muaj nws keeb kwm nyob rau hauv thaum ntxov 20th caug xyoo. Lub tswv yim ntawm kev siv hlau rau kev txiav cov hom phiaj hnub rov qab mus rau lub xyoo pua 19th, nrog kev txhim kho ntawm helicoidal lossis hlau pob zeb pom, uas tau siv los txiav marble. Txawm li cas los xij, qhov kev nce qib tseem ceeb uas ua rau niaj hnub pob zeb diamond hlau pom tau pib nyob rau hauv nruab nrab -20th caug xyoo.
Nyob rau xyoo 1950, nrog rau kev tshwm sim ntawm cov khoom siv pob zeb diamond, cov kws tshawb fawb tau pib sim nrog embedding pob zeb diamond hais rau hauv hlau saws. Qhov kev tsim kho tshiab no zoo heev txhim kho qhov kev ua tau zoo thiab kav ntev ntawm cov saws. Thawj daim ntawv thov kev vam meej ntawm pob zeb diamond hlaws hlau saws hauv mining tau tshwm sim hauv xyoo 1953. Los ntawm xyoo 1970, pob zeb diamond hlau pom tshuab tau loj hlob tuaj thiab pib siv dav hauv kev tsim kho thiab kev lag luam pob zeb.
