{HEAD ~ An input device} 34, wherein the step portion has a curved side surface, {TAIL ~ the operating unit} has a curved portion, and the curved portion of the operating unit fits into the curved side surface of the step portion 
{ HEAD ~ An input device } 34 , wherein the step portion has a curved side surface , { TAIL ~ the operating unit } has a curved portion , and the curved portion of the operating unit fits into the curved side surface of the step portion
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH