Theodore Checkos inventor

http://www.freepatentsonline.com/search.html - shows three patents for him, as Theodore and Theodore K. Checkos.

From ssdi.rootsweb.com, Theodore Checkos was born 26 Apr 1903, and died 3 Jan 1993, and his last residence was in Riverside, California. The name is not common; also listed are Violet, possibly his wife, Nicholas, perhaps his brother, and Larry, maybe his son.

The California death index - http://vitals.rootsweb.com/ca/death/search.cgi - gives his full name as Theodore Konstantine Checkos, whose father's last name was "Chakas", and who was born in Illinois.