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スプリアスモード抑圧形・縦振動音片の解析
Get PDF論文(Article)This paper deals with a theoretical analysis and some experimental results on the longitudinal resonator which is suttable for frequencies above 30KHz. In order to suppress the unwanted flexural modes, the piezoelectric ceramics are bonded on four surfaces of the slnder resonator with square cross sections, and the electrode of a piezoelectric ceramic is formed like a sinusoidal function for the longitudinal resonator to vibrate only in the wanted mode. Here are discussed the equivalent circuit constants and the apparent resonant frequency of the resonator in due consideration of the impedance of the piezoelectric ceramics, and the results are compared with those of resonators with the normal electrode and the partial one. Furthermore, the response curves of a differential type mechanical filter consisting of the longitudinal resonators are shown. These results show that the sine-shaped electrode is effective in suppressing spurious responses in the mechanical filter consisting of the longitudinal resonator
簡単な正イオンの発生源とその応用について
Get PDF論文(Article)This is a report on some experimental results of the measurement of the positive ion emission currrent from the electric heater which is made from SiC, and the application of the positive ion to the neutralization of negative charge. The positive ion emission current from SiC heater has much value and good stability for some considerable hours. Electrification on the silk yarn, turns to almost negative polarity, when the warping machine of the silk yarn operates. Therefore, some attempts have been made to neutralize the negative charge on the silk yarn by the positive ion emission from SiC heater. Thus, it has been made clear that the satisfactory result can be obtained by using the combination of the SiC heater and the electric fan
50KC以下の搬送周波数における電気・機械濾波器
Get PDF論文(Article)With the improvement of communication facilities, an electromechanical filter is useful for the multiple communication and the prevention of channel interference. At present time, the centered frequency range of these filters which is from 50KC to 500KC is used. But, of late, we require an electromechanical filter for frequencies below 50KC or above 500KC. In this paper, the design method and the experimental results of an electromechanical filter for frequencies below 50KC are described. These results obtained here show that the electromechanical filter is practically used as electrical wave filters. The filter used here is the electromechanical one which uses dominant mode and which consists of two couplers and two resonators. The resonators are flexurally vibration metal bars which are coupled at their nodal point with torsionally vibrating bars. An electromechanical filter is equipped with a pair of electromechanical transducers for exciting and detecting the vibrations. The electromechanical transducers used here are two kinds of types of the electromagnetic transducers and of the piezo-electric ones. The piezo-electric transducer consists of two pieces of piezo-electric material with a metal sheet sandwitched between them and the piezo-electric material is a barium titanate ceramic. The electromagnetic transducer is useful for mechanical filter for frequencies below 5KC, while the piezo-electric transducer is available for mechanical filter with frequency range between 10KC and 50KC, and the latter one has a simple construction and low spurious, because of the piezo-electric transducer of partial electrode suppressing the higher mode vibration. In the last chapter, a few examples of new construction of electromechanical filter and a test of its filter are described
リチウム二次電池の性能評価の標準化
Get PDF論文(Article)Cell performance of active materials is generally evaluated electrochemically by using a test cell which consists of the specially designed half cell for research purpose. However the results obtained often depend on the test cells with different configuration, and this makes the exact evaluation difficult. These cells consist of multiphase system such as active material, electrolyte, conductive filler, current collector and so on, and all the electrons or ions pass through each boundary layer during cell operation. Thus the path-ways of current flow would be profoundly affected by the state of these interfaces. In this report, we focused on the functions of hetero-contact phases between the cell component materials to design a test cell which enable us to know real cell performance of the active materials. Combinations of the electrolytes and the current collector materials, function of the conductive additive (carbon material) and the anodic oxide film on aluminum current collector were examined by using our unified test cell. The relationship between the cell performance and these functional hetero-contact phase at the cell component materials were discussed in detail
誘電形機器の研究
Get PDF論文(Article)Chapter 1. General Consideration Chapter 2. Construction and Theoretical Cosideration Chapter 3. Design Procedure of Electrode Dimensions Chapter 4. High Frequency Generator Chapter 5. D.C.-A.C. Converter Chapter 6. Deviation Detector Chapter 7. Conclusion Pleviously the author presented the report of study on dielectric type (Condenser type or electrostatic type) high frequency generator. Moreover the rotating machine and the apparatus of this type are utilized to control or measuring elements such as D.C.-A.C. converter, tachogenerator and deviation detector (or position detector, namely, transducer to electrical signal from small linear or angular displacement). Chapter 2 presents the discusions of general construction of this type and the theoretical treatments that are applicable to the all machines and devices above mentioned. Chapter 3 is concerned with the design of the optimum electrode dimensions. To develop this method, it is necessary to appreciate the variation of interelectrode capacity. For this purpose, the wave form of variation of this capacity is measured and the values of C_0, C_1, etc. are measured concerning some representative types of electrode construction such as plate electrode, rectangular teeth and trapezoidal teeth electrode, where C_0 is the mean value of this capacity and C_1 is the amplitude of the fundamental component of variation of this capacity. Chapters 4 through 6 contain the applications of this method to each machines and devices. In addition, it is emphasized that this method is not only applicable to the dielectric type, but also to the control elements of the induction type and the other electric machinery such as printed circuit servomotor. Chapter 4 gives several conditions to obtain maximum output for various loading states and some numerical examples. By these examples, it is clarified that this machine has more excellent output characteristics than an electromagnetic induction type alternator within the frequency range of 10KC - 100KC. Paragraph 4.9 and chapter 5 treat rotating machines of this type which are utilized to control devices. The former cotains detailed treatments of tachogenerator and the latter, D.C.-A.C. converter. Chapter 5 gives some experimental results about the stability of the converters which is affected by the drift of the contact potential difference. Chapter 6 presents theoretical and experimental treatments of the deviation detector of both types, namely, amplitude type (the deviation is indicated by the amplitude of electrical signal) and phase type. Besides the dielectric type, there are many others, that is, Inductosyn, Vernier resolver and Telecote, etc..But the amplitude type has a superiority on its voltage sensitivity over others and the phase type is suitable for the digital counting detector
押込みかたさとバウシンガー効果(第1報)
Get PDF論文(Article)The indentation hardness of 0.57% carbon steel specimens, which were applied 5.6% and 10.7% tensile or compressive prestrains, was measured by a 10mm diameter quenched steel ball, and the following results were obtained : (1) Owing to the Bauschinger Effect, the hardness of the specimens applied tensile strain was smaller than that of the specimens applied the same amount of compressive prestrain as the tensile strain. By low temperature ageing, the hardnes of these specimens increased, but the hardness of the tensile prestrained specimens was still smaller than that of the compressive prestrained ones. It is clear that low temperatme ageing can not remove the Bauschinger Effect completely. (2) To make the series of p_m / c - 20 (d / D) curves obtained from the hardness measurements of tensile prestrained specimens coincide with the true compressive stress strain curves of the specimens, as D. Tabor suggests, the constant‘c' must be set about 3.15 to 3.20, larger than 2.8, given by Tabor; where p_m represents mean indentation pressure of the steel ball with diameter D ; d the diameter of indentation It can be considered that this may be caused by the isotropy of the Bauschinger Effect. In consequence of the low temperature ageing of these specimens, the value‘c' comes near to 2.8, because the Bauschinger Effect is partly removed. (3) The Meyer index‘n' for indentation hardness measurements of tensile prestrained specimens is larger than that of compressive prestrained ones, and comes near to 2.5, whlie the value‘n' approaches 2.0 when the specimens are aged. These phenomena can be said to have resulted from the Bauschlnger Effect
薄膜トランジスタの動的圧電特性に関する実験
Get PDF論文(Article)In this paper, it is emphasized that CdSe thin film transistor (TFT) may be used as a functional device having the faculty of both the electro-mechanical transducer of high sensitivity and the ordinary amplifier. Our results showed that the drain current level of TFT was modulated by the dynamic stress given on the glass substrate of TFT, using ultrasonic horn vibrating at the frequency of 20.0 KHz. The maximum drain current modulation observed was 81% at the vibration displacement ”d” of 8 microns at the tip of this horn impinging on the center of the substrate. Metal-SiO-CdSe-Metal thin film capacitor stressed dynamically showed sinusoida out put voltage of 4.2 mV by the piezoelectric effect of CdSe at ”d” of 7.4 microns. From these results, it was confirmed experimntally that the modulation mechanism of the drain current of the TFT was attributed to the variation ΔVo of gate-offset voltage Vo due to the applied dynamic stress
一端閉塞の多孔質弾性円管内非定常流(管長が伸びあるいは縮む場合の線形理論)
Get PDF論文(Article)Unsteady flow of a viscous, incompressible fluid in a semi-infinite circular tube with a porous, elastic wall whose length contracts or expands with time, but whose cross-section does not vary, is studied considering the effects of suction or injection on the wall. Laminar, similar solutions with respect to space and time are obtained analytically. Velocities, pressure, frictional drag, power and work of fluid are analyzed. The elastic motions of the tube have two typical cases one is from the finite length to another finite one, and the other is from the finite length to the infinite or infinitely small one, if it may be possible. The former has a tendency to induce the remarkable compensating flow in the center of the tube, while the latter causes the flow to have the core region with the boundary one. There are the critical conditions of suction and injection on the wall in accordance with the conditions of motion of the wall either contracting or expanding in an axial direction. The conditions of suction and injection are divided into two parts, giving a classification of the situations of the induced flow fields
グラフ理論による通信網の近似解析
Get PDF論文(Article)Relay stations of a communication net are mutually connected under many different conditions, and hence detailed comparisons of these capacities is very difficuit. It is described that the capacity of relay station can be analyzed by a method determining the path on graph theory. This capacity of communication net is graph-theoretically defined, and its characteristics are illustratively examined by the abovementioned method. Further, two approximate methods for numerical analyses are proposed and applied to an actual telphone circuit of Tohoku electric power company
PVCの高温水中での脱塩化水素
Get PDF論文(Article)Thermal degradation of PVC in water was carried out using a stirred pressure reactor at 240～280 ℃. Ca(OH)_2 or CaCO_3 was used as HCl scavenger and dispersed in water. Although HCl produced is reduced to CaCl_2 on the face of granular scavenger, its effect is preserved because CaCl_2 dissolves in water immediately. When PVC was heat treated at 270～280 ℃ for 1h on such conditions, both dehydrochlorination of PVC and the recovery of HCl as CaCl_2 were nearly perfect