Automatic player musical instrument, automatic playing system incorporated therein and overheat protector for automatic playing system

摘要

An automatic player piano is equipped with solenoid-operated actuators for moving keys in automatic performance without fingering of a human player, and an overheat protector is provided for the solenoid-operated actuators so as to prevent the solenoid-operated actuators from overheat; the overheat protector includes not only a temperature sensor and a rescuer but also an information processor, and a computer program runs on the information processor so as to realize a temperature rise estimator for estimating a solenoid temperature on the basis of the amount of current flowing through the solenoid and an environmental temperature determined through the temperature sensor estimator and an overheat detector so as to find an overheated solenoid, thereby making the rescuer interrupt the current for preventing the solenoid-operated actuator from the overheat.