▁( now ▁the ▁Os aka ▁Works ); ▁Start ed ▁production ▁of ▁en am el ▁w ires ▁▁ 1 9 2 0 ▁- ▁Sum it omo ▁Electric ▁W ire ▁& ▁C able ▁Works ▁incorpor ated ▁as ▁a ▁limited 　 company ▁▁ 1 9 3 1 ▁- ▁Start ed ▁production ▁of ▁c ement ed ▁car b ide ▁tools ▁▁ 1 9 3 2 ▁- ▁Start ed ▁production ▁of ▁special ▁steel ▁w ires ▁▁ 1 9 3 9 ▁- ▁Company ▁name ▁changed ▁to ▁the ▁current ▁name , ▁Sum it omo ▁Electric 　 Ind ust ries , ▁Ltd . ▁▁ 1 9 4 1 ▁- ▁Open ed ▁the ▁It ami ▁Works ▁▁ 1 9 4 3 ▁- ▁Start ed ▁production ▁of ▁v ibration - proof ▁rub ber ▁products ▁and ▁fuel ▁t anks ▁▁ 1 9 4 6 ▁- ▁Open ed ▁a ▁brand ▁office ▁in ▁Tokyo ▁( now ▁the ▁Tokyo ▁Head ▁Office ) ▁▁ 1 9 4 8 ▁- ▁Start ed ▁market ing ▁s inter ed ▁pow der ▁metal ▁products ▁▁ 1 9 4 9 ▁- ▁Enter ed ▁into ▁the ▁construction ▁business ▁of ▁overhead ▁transmission ▁lines ▁▁ 1 9 5 1 ▁to ▁ 2 0 0 0 ▁▁ 1 9 5 7 ▁- ▁Del iver ed ▁the ▁first ▁Japan - made ▁television ▁broadcast ing ▁anten nas ▁▁ 1 9 6 1 ▁- ▁Open ed ▁the ▁Y ok oh ama ▁Works ; ▁Del iver ed ▁the ▁w iring ▁har ness es ▁for ▁four - w heel ▁vehicles ▁for ▁the ▁first ▁time ▁in ▁its ▁history ▁▁ 1 9 6 2