Eishinjuku Dojo was named by Hiroshi Ozawa.  The "Ei" kanji is not the most common kanji for this sound and in this context comes from this writing by Mencius.  Eishinjuku was the name of a private school that Ozawa Sensei's grandfather attended and the name Eishingijuku was added to the Kobukan name by Ozawa's father when he inherited the dojo.