US Patent 10201470 Device for delivery of resonant frequencies to treated muscles

A drumming device for delivering a repetitive percussive strike to muscles below a skin surface comprises a main housing enclosing an electric motor with a shaft having a fixed rotational speed, a drive pulley, a toothed belt encircling the drive pulley and a driven pulley with an integral cam mounted on the pulley such that the rotating shaft causes the driven pulley to rotate at a predetermined number of cycles per second, the assembly causing a repetitive, reciprocal movement of a plunger body a fixed distance and at 16.6 cycles/sec, the plunger movable in a downward direction following contact with the cam, such that the plunger reciprocates within the housing when the cam member contacts the plunger causing the plunger shaft to move laterally outward. When the massaging device is properly position in contact with the skin the moving plunger causes muscle spindles to vibrate at their resonant frequency.