Keyboard apparatus for electronic musical instrument

摘要

A keyboard apparatus for an electronic musical instrument has a metallic keyboard chassis and a balance rail provided on the keyboard chassis. A plurality of pins are provided on the balance rail. The pins and the balance rail constitute fulcrums for swingably supporting white keys and black keys. A hammer is provided in a rear side of each of the white and the black keys so as to be swingable by swinging of each of the respective keys by a second fulcrum comprising oval cross sectional shafts extending outwardly from the side surface of one of the hammer and a bearing member, the side surface extending perpendicular to a direction of swing movement of the hammer and a pair of bearing recesses for pivotally receiving the shaft, the bearing recesses being formed in the other of the hammer and the bearing member. Each of the bearing recesses has a guide slot for guiding each of the shafts from outside into the bearing recess for assembling. A split groove is provided in the other of the hammer and the bearing member for receiving the one of the hammer and the bearing member. First abutment surfaces are provided so as to project in an axial direction of the shafts from the side surface of the one of the hammer and the bearing member around the shafts, the first abutment surfaces being in sliding contract with the slit groove. Second abutment surfaces are provided by reducing the width between the side surfaces and lateral vibration preventing surfaces are provided inside the split groove in close proximity to the second abutment surfaces.