PURPOSE: To provide a 'click feeling' to the operator, with simplified construction, by stretching the respective coil portions in the mutually opposite directions, which portions are the upper and lower ends of a compression coil spring loaded in a case forming arm portions respectively.

CONSTITUTION: A compression coil spring 8 has its free length l made sufficiently long in comparison with its coil diameter (d), and coil portions provided at its respective upper and lower ends are caused to open in opposite directions by one turn to thereby form respective arm portions 18, 19. When pushed down, a key top 5 slides at its engaging pieces 15, 15,... along the respective channels 16, 16,... of a wound body 3 so that the compression coil spring starts contracting. The compression coil spring 8 having its free length l made sufficiently longer than its coil diameter (d), its middle portion is bent during compression so that it is buckled. In this case, its repulsive forces toward the key top 5 suddenly changes because of the buckling of the compression coil spring 8, so that a 'click feeling' is transmitted to the operator.