日本音響学会誌
Online ISSN : 2432-2040
Print ISSN : 0369-4232
28 巻, 3 号
選択された号の論文の10件中1~10を表示しています
  • 柴山 乾夫, 佐藤 弘明
    原稿種別: 本文
    1972 年 28 巻 3 号 p. 97-107
    発行日: 1972/03/10
    公開日: 2017/06/02
    ジャーナル フリー
    This paper describes a general analysis of the torsional circular wave guide with steps based on the infinite matrix method and its application to the three-element torsional wave guide. The details of the analysis are described in Sec. 2. As a result, the dynamic characteristics of a cascade circuit with many steps can be given by the three foundamental equations, i. e. Eq. (7) for the uniform section, Eq. (16) for the velocity components and Eq. (21) for the stress components at each step. In Sec. 3, the shrot-circuit admittances (see Figs. 5 and 6), the distribution of axial resonant frequencies (see Figs. 7, 8, and 9) and the frequency filtering characteristics are investigated for several geometrical configurations of the wave guide as shown in Fig. 3. The results are discussed by comparing the exact theory with the well-known one-dimensional theory, from the point of view to apply the distributed constant design theory used in an electrical circuit to the mechanical system. In order to clarify the reason why the difference from the one-dimensional takes place, the aspects of the wave disturbance at each step are studied, through the particle velocity distribution (see Figs. 11 and 12), the condition of higher mode excitations (see Fig. 13) and the comparison of the relative axial distributions (see Fig. 14). As the results of these studies, it is stated that, i) in the inner part of vibrator, the disturbance appears conspicuously as a local deformation of radial distribution, and then the phase of the particle velocity advances forward along the propagation axis more than that of one-dimensional theory, and consequently, ii) at the input or output terminal of the vibrating circuit, we observe such phenomena as the axial resonant frequencies are lower than the values obtained by the one-dimensional theory and the frequency characteristics are widely different from designed ones. Especially, when the center frequency of a filter is taken at the resonant frequency f_3, it is noted that the admittance characteristic is deformed from the design value even if the radius of the wave guide is smaller enough than the wavelength. The working attenuation charcteristic, therefore, has a large ripple as much as a few decibel (see Fig. 10). As a solution of this problem, the authors have proposed the shortening of length of the slender wave guide as shown in Fig. 10. Finally, a number of experiments are found to support the theory very well as seen in the resonant frequency distribution shown in Figs. 7 and 15.
  • 富川 義朗
    原稿種別: 本文
    1972 年 28 巻 3 号 p. 108-116
    発行日: 1972/03/10
    公開日: 2017/06/02
    ジャーナル フリー
    Many constructions of the mechanical filter with attenuation-poles have been published up to the present time, but the greater part of them is rather complex and large for construction to obtain attenuation-poles. The mechanical filter with attenuation-poles consisting of multi-mode resonators has been published in recent years and it is made clear that the filter is suitable for miniature size, but the filter has a weak point that attenuation-poles are not set up independently, because band-width and attenuation-poles are decided with the same coupler. In this paper that a new type of mechanical filter is proposed, one with attenuation-poles which are obtained easily by couplers not concerned with band-width. This paper describes the construction and experimental result of the filter with attenuation-poles of composite type consisting of two multi-mode discs and some couplers. As multi-mode disc, a disc in the orthogonal flexural double mode B_&lt11&gt having one nodal diameter and one nodal circle is used. Constructions of the filter with attenuation-poles published until now, in the beginning, are classified into some groups (Table 1) and arranged by their equivalent lattice circuits to clean up principles of the filters with attenuation-poles and the position in the groups of the filter described here (Figs. 1 and 2). The construction (Fig. 3) and its equivalent circuit (Fig. 4) of the new filter with attenuation-poles are shown next. Its equivalent circuit is based on the circuit of T type transferred from Jaumann circuit of the double-mode disc (Fig. 5), in which cutting off some part of the disc for adjustment of two resonant frequencies is regarded as attaching negative equivalent mass. Relation between resonant frequencies obtained from the circuit of T type and the ones measured practically is described in the appendix (Figs. A-1 and A-2). It is pointed out that modes of series arms of T type equivalent circuit are those of which nodal diameter is different at an angle of geometrical 90 degrees from the diameter of B_&lt11&gt mode measured practically (Figs. 6 and 7). Finally, there is described that design method of the filter applying image-parameter method to the equivalent circuit in which electrical inductances are added in parallel at both electrical end terminals (Fig. 8), with one example of the design and experimental result of the filter with attenuation-poles (Table 2 and Fig. 9).
  • 根本 佐久良雄, 森 栄司
    原稿種別: 本文
    1972 年 28 巻 3 号 p. 117-126
    発行日: 1972/03/10
    公開日: 2017/06/02
    ジャーナル フリー
    Most vibrators used for ultrasonic power applications are longitudinal vibrators. However, progress in ultrasonic power applications demands the development of new types of vibrators. . . torsional vibrators. One example among them is a magnetostrictive torsional vibrator, which has been developed by the present authors. It is in practical use, e. g. , as a surgical operating tool of senile cataract of human eyes etc. But the magnetostrictive torsional vibrator has the following difficulties: (1) The output power of a single vibrator is insufficient in order to be used for ultrasonic machining etc. (2) It is hard, in view of its construction, to drive a plural vibrators in cascade for sufficient power. (3) It is also difficult to attach a vibration monitor to it. (4) A load and the vibrator must be joined together by adhesion, which often comes off from the vibrator, thus lowering the reliability. Under the notion that a bolt-clamped Langevin type electrostrictive torsional vibrator has the possibility of overcoming the difficulties mentioned above, the present authors examined it and found that it has some merits, which a magnetostrictive one does not have, and it is adoptable for ultrasonic power applications. In making up an electrostrictive torsional vibrator for ultrasonic power applications, we adopted bolt-clamped Langevin type'' as shown in Fig. 1-b, using ceramics polarized so as to vibrate in thickness shear mode with Langevin's metal blocks to lower the resonant frequency of the vibrator and to obtain an arbitrary resonant frequency from the same disc. The matal blocks (1), (4) and ceramics (2), in Fig. 1-b, are clamped by bolt (3) and nut (5). In order to polarize the electrostrictive ceramics circumferentially as one body, silver electrodes (hatched portion) are glazed on the ceramics as shown in Fig. 3, and they are polarized eight times one division after another. Polarizing conditions are as follows: (1) In 160℃ silicone oil bath, (2) in an electric field of 13kV/cm between adjacent electrodes, (3) electric field was impressed for 20 minutes per one element. But these conditions are not always best. Nodal plane of the vibrator shown in Fig. 4 is set at C plane. The frequency equations of the vibrator shown in Fig. 4 are expressed as eq. (4) about the division A-B-C, and as eq. (5) about C-D-E-F. In Figs. 5 and 6, there are shown trially made vibrators, the latter has the cascaded structure of A-B-C division of the vibrator shown in Fig. 4. As is seen in the figures, both vibrators have resonant frequencies cloes to the designed one. Torque generated at the small element shown in Fig. 7 is expressed as eq. (9), using Elasto-Piezo-Dielectric Matrix written as eq. (6) or Table 1. Torque generated in the whole cross-section of transducer ceramic is expressed as eq. (10). Putting the integrand of eq. (10) as eq. (11), this is given as Table 2 with the ceramic polarized as Fig. 2. The relation between output torque and the dimensions of the vibrator including material constants is given by this value. The authors show in section 5. 2. 4. that the torque calculated and measured agree well. This electrostrictive torsional vibrator has also some weak points ; (1) It requires polarization as many as eight times to make one thickness-shear mode ceramics. (2) Therefore it is difficult to make small sized vibrators. (3) The whole volume of the electrostrictive ceramics is not used effectively. Selection of the torsional vibrators, magnetostrictive or electrostrictive ones described in this report is not decided easily, but they should be selected according to circumstances.
  • 伊藤 勝彦, 森 栄司
    原稿種別: 本文
    1972 年 28 巻 3 号 p. 127-135
    発行日: 1972/03/10
    公開日: 2017/06/02
    ジャーナル フリー
    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.
  • 森 栄司, 金子 誠司, 大川 順弘
    原稿種別: 本文
    1972 年 28 巻 3 号 p. 136-137
    発行日: 1972/03/10
    公開日: 2017/06/02
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  • 森 栄司, 高木 尚, 金子 誠司
    原稿種別: 本文
    1972 年 28 巻 3 号 p. 138-
    発行日: 1972/03/10
    公開日: 2017/06/02
    ジャーナル フリー
  • 山本 美明
    原稿種別: 本文
    1972 年 28 巻 3 号 p. 139-145
    発行日: 1972/03/10
    公開日: 2017/06/02
    ジャーナル フリー
  • 尾上 守夫
    原稿種別: 本文
    1972 年 28 巻 3 号 p. 146-152
    発行日: 1972/03/10
    公開日: 2017/06/02
    ジャーナル フリー
  • 柴山 乾夫
    原稿種別: 本文
    1972 年 28 巻 3 号 p. 153-158
    発行日: 1972/03/10
    公開日: 2017/06/02
    ジャーナル フリー
  • 鷲沢 茂貴
    原稿種別: 本文
    1972 年 28 巻 3 号 p. 159-164
    発行日: 1972/03/10
    公開日: 2017/06/02
    ジャーナル フリー
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