Nidec Corp. in Kawasaki, Japan.Takaaki Iwabu/BloombergShares of Nidec, the precision motor maker founded by Japanese billionaire Shigenobu Nagamori, plunged by their daily 500 yen limit (19%) on Tuesday after the Tokyo Stock Exchange announced its decision to remove the 52-year-old company from the benchmark Nikkei 225 and Topix indexes.The exchange designated on Monday Nidec as a “security on special alert.” It cited reasons including lax internal controls and an ongoing investigation over a deepening acco ...