To allow an emissive surface to drive by transverse vibration with the same amplitudes everywhere which does not include longitudinal vibration at all.

A tool horn body 2 is formed so as to be a stepped prismatic shape from a large-sized part 2a and a small-sized part 2b. A fixing face 7 for fixing to an elevation mechanism is formed at the upper end part of the large-sized part 2a. An emissive surface 8 for performing working such as welding is formed at the lower end part of the small-sized part 2b. The adjoining two side faces of the tool horn body 2 are provided with a first fixed horn 4 driven by a first longitudinal oscillator 3, and a second fixed horn 6 driven by a second longitudinal oscillator 5, respectively. The face fitted with the second fixed horn 6 in the tool horn body 2 is provided with a first slit 9 corresponding to the first longitudinal oscillator 3. The face fitted with the first fixed horn 4 in the tool horn body 2 is provided with a second slit 10 corresponding to the second longitudinal oscillator 5. The oscillation of the emissive surface 8 is made into the transverse oscillation by providing each slit 9 and 10.