Touch control apparatus of electronic musical instrument

1. Hardware Configuration of an Embodiment

1.1. Configuration of Keyboard Portion 10

[0029]Next, configuration of a keyboard portion 10 of an electronic piano according to an embodiment of the present invention will now be described, referring to FIG. 1. Although the keyboard portion 10 is formed of a plurality of keys and their peripheral circuits, FIG. 1 shows the configuration of only one of the keys. A key 30 can freely pivot about a fulcrum 34. In this figure, the front of the key 30 is situated on the right side. More specifically, an end on the front side is to be depressed downward by a user. Above a rear end of the key 30, a solenoid unit 20 is provided. Inside the solenoid unit 20, a solenoid 24 is formed of a conducting wire wound to be approximately shaped like a cylinder. In addition, a yoke 22 is formed of a ferromagnet which covers the upper and lower end surfaces and the rim surface of the solenoid unit 20. The yoke 22 and the solenoid 24 form a stator of the solenoid uni