Keyboard structure of electronic keyboard instrument

A keyboard structure of an electronic keyboard instrument, comprising:

• keys having key main bodies thereof connected through thin plate-like hinges to base ends at a rear of the keys and adapted to be pivoted about the base ends as key fulcrums in a key depression or release direction;
• an integral key frame fixedly provided relative to an instrument body and adapted to fixedly support the base ends of said keys, the key frame extending over the width of said keys, and having a recessed groove for receiving said base ends;
• a stopper fixedly provided in at least one of the instrument body and said key frame;
• and
• stopper contact portions provided in the key main bodies and disposed close to or in contact with said stopper in a key-nondepressed state,
• wherein said thin plate-like hinges of the keys are formed to extend downward from rear ends of the key main bodies in a direction intersecting key depression surfaces of the key main bodies and said thin plate-like hinges of the keys extend in a direction parallel to a key arrangement direction, and
• wherein when any of the key main bodies is urged rearward at least in the key-nondepressed state, the stopper contact portion corresponding to the urged key main body is made in contact with said stopper to thereby restrict a rearward displacement of the urged key main body.