抄録
In the application of longitudinal vibration, a conventional vibration system is almost of one-dimensional construction such as solid horn. And high power vibrational energy could not get because of the radial coupling of the vibration. But the authors are sure it may be more convenient that ultrasonic energy can be transmitted from the direction of driver to the other and also it is able to be concentrated by parallel operation of drivers and to be divided into plural loads from one vibration source. From this point of view, the authors have devised (we call L-L type converter) the directional converters of longitudinal vibration as shown in Fig. 1. These converters are same fundamental behavior of vibration so that two longitudinally vibrational rods of half wavelength are connected each other at their node of vibration (as shown in Fig. 5) and also it has two resonant frequencies (as shown in Table 1), one is the same phase each other at their free end surfaces A and B, another is the opposite phase, and does the ratio of vibrational velocity between A and B. Uniform rod with rectangular cross-section as well as the converter has three resonant frequencies, each of which is in-phase-mode, quasi-in-phase-mode and anti-phase-mode. In all cases, the resonant frequency of the in-phase-mode was higher than that of anti-phase-mode. (as shown in Table 2) The authors were analyzed the converter by setting up an assumption from these vibrational characteristics, and led the equation to needing design, and also we designed, devised and measured the new converter. The result was dotted within one percent to the given resonant frequency, three percents to the calculated ratio of vibrational velocity in free end surfaces.
