Air-driven vibrator

In a vibrator comprising a rigid body having a substantially disk-shaped working chamber defined by a cylindrical side wall and a pair of opposite end walls extending perpendicular to the axis of the chamber, a substantially disc-shaped vibratory element smaller in size than said chamber and received in said chamber for oscillatory movement, means for injecting a gaseous working fluid under pressure into said chamber in a direction tangential to said chamber to generate a swirling stream of working fluid therein, and, exhaust means for exhausting used working fluid out of said chamber, the improvement wherein axial end faces of said vibratory element are machined substantially flat, said vibratory element having an axial bore extending therethrough along the axis thereof, an insert member protruding axially outwardly of said axial end faces of said vibratory element being securely inserted into said axial bore of the element to prevent the vibratory element from sticking to the end wall of the chamber when the vibrator is not operated.