| 摘要 |
A fretted instrument consists of a body with a bridge for fixation of string ends, which is connected to fingerboard with nut, pegbox for fixation of second string ends, wherein for action on strings at strictly bounded points of fingerboard the instrument comprises a keyboard comprising a set of separate keybuttons each arranged at cylindrical recess of fingerboard, along the strings. The keybutton comprises a movable head with opening for string passage and boss for pressing thereon, axle, spring, screw arranged coaxially and a ball inserted to the opening of the movable head. The ball is rest on the movable head, longitudinal groove at the axle and is closed by spring. The keybutton is rigidly fixed to the fingerboard through the axle, the spring made as helical cylindrical compression spring is rest by ends on the axle and movable head and comprises spring coils without gap in zone of ball mounting. On the axle end an adjusting washer with different in height bosses is mounted, this covers the longitudinal groove, this makes it possible to change a size between the string and upper surface in the movable head opening. In the axle recesses are made for bosses of adjusting washer, this is fixed to the axle by screw. When using the keyboard, frets are not mounted to the fingerboard, keybuttons are mounted, fixed parts of those distinguish string sounds into parts. |
