Patent ID: 7156201
Filing Date: 2007-01-02
Classification: A61B,B06B

Abstract:
1. An ultrasonic resonant rod waveguide-radiator having a defined length, an entrance surface and an exit surface, comprising: at least three cylindrical sections, including a first cylindrical section comprising the radiator's entrance surface and a second cylindrical section comprising the radiator's exit surface; at least two sections of variable cross-section; wherein said at least three cylindrical sections and said at least two sections of variable cross-section are arrayed in alternating positions and acoustically rigidly connected together; wherein the ratio of the cross-sectional areas of the exit surface and the entrance surface is approximately 1:1; wherein the waveguide-radiator's total length is equal to a multiple of half the length of an acoustic wave in the waveguide-radiator material, taking into account a geometrical dispersion; wherein the length of each of said at least two section of variable cross-section is no less than the value of Log(N)/k, where N is the ratio of diameters of the cylindrical sections adjacent to said section of variable cross-section and where k is the wave number, which is equal to ω /C where ω is the frequency of ultrasonic vibrations and C is the speed of sound in liquid; wherein the sum of the length of the second cylindrical section and the length of the section of variable cross-section adjacent to said second cylindrical section is at least 30% of the total length of the waveguide-radiator.