The design and development ofa power circulating rollinl Contact disc machine is descn"bed. Each disc is medlaDially coupled to a Iepamely excited d.c. electtical machine whose armatures are CODDected electtially.When the discs develop ttaaiOD. power circulates by one machine acting as a motor and the other as a generator.In this way conuoUed ttactioo with a ltepleas variation of sliding speed can be m.inftifted between the rol領(lǐng) discs. TE 73 高速雙輥試驗(yàn)機(jī)