Patent attributes
Grounded, circular movable electrode and divided electrodes, formed on a surface of a circular printed board, are opposed to each other via a double-face tape, functioning also as a spacer, with a slight gap interposed therebetween. As a pad is struck with a stick, the gap between the movable electrode and the divided electrodes changes so that capacitance between the movable electrode and the divided electrodes changes, in response to which signals are output from the divided electrodes. The divided electrodes are sandwiched between the grounded movable electrode and a grounded shielded electrode and thus are not influenced from external disturbances. As the pad is struck with the stick, the gap and hence capacitance between the movable electrode and any of the divided electrodes in the struck position changes, in response to which signals are output from the divided electrodes
