Rotary valve for brass instruments

摘要

The rotary valve comprises a rotor (3), on the outer peripheral surface of which, switching paths are formed in order to change the pipe length of the resonance pipe. The valve housing has a cylindrical shape in which the rotor is inserted. There are holes at either end of the housing. A bottom covering covers an opening from one end of the valve housing, and a top covering covers the other end of the valve housing. The internal diameter of the valve housing has the same bore diameter along its longitudinal direction. The outer diameter of the rotor is slightly smaller than the diameter of the outer running track of the radial ball-bearing.