One notices a funny thing about the translators rendering of this word. When KURIOS is referring to Jesus it is translated as LORD Jesus. (Luke 24:3) If the translators were consistent and KURIOS really meant Jehovah, then it would properly be rendered in English as Jehovah Jesus. I wonder what gives?!?
kurioV is simply an honorific. In modern Greek, it corresponds to the English "Mister" (You address your teacher as Kyrios)
Because of that, it's usage floats with context and grammar. It does not take the place of a proper name on a permanent basis.
For example, Matthew 22:44 reads:
eipen o kurioV tw kuriw mou
"The LORD said to my Lord" (KJV)
It is generally understood that the first usage is a reference to God while the second usage is simply a title.