Actually, there were three companies!
My notes show the J. B. Miller Keyless Lock Company, of Kent, Ohio, started in 1888. This was often abbreviated as J.B.M.K.L.
In 1944 or 1945 the company was acquired by Gougler, still of Kent, Ohio. The locks were marketed under the name Gougler Keyless Locks. Around 1965 the company name used in advertising was the C. L. Gougler Machine Company, Lock Division.
Some time in the 1970s, Gougler sold the company to a family named Miller (no relation to the original J. B. Miller) and it continued to operate as the Miller Company and/or Miller Industries, of Columbus (not Kent), Ohio. Locks were marked Miller Keyless Locks. This company went out of business a few years later.