Automatic player piano having frame structure self-aligned with keyboard for exactly positioning key actuators arranged in staggered manner

摘要

An automatic player piano has solenoid-operated key actuator units under a keyboard mounted on a wooden key bed, and the solenoid-operated key actuator units are supported by a frame structure inserted into a slot formed in the wooden key bed and bolted to metallic bracket members screwed to the wooden key bed; when the frame structure is taken out for a repairing work, the bracket members are never removed from the wooden key bed, and the bolt holes of the wooden key bed are never undesirably enlarged.