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Hisashi NISHIMURA
1986 Volume 52 Issue 476 Pages
1125-1131
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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Katuhisa FUJITA, Tomohiro ITO, Keizo OKADA
1986 Volume 52 Issue 476 Pages
1132-1140
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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Yasushi NIITSU, Yuzi NODA
1986 Volume 52 Issue 476 Pages
1141-1147
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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Akira SHOJI
1986 Volume 52 Issue 476 Pages
1148-1154
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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Akira SHOJI
1986 Volume 52 Issue 476 Pages
1155-1161
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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Hirokazu OSAKI, Susumu KIKUCHI, Risei USUDA
1986 Volume 52 Issue 476 Pages
1162-1169
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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Hitoshi TAKEDA
1986 Volume 52 Issue 476 Pages
1170-1176
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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Toshihiko ASAMI, Hisayoshi SEKIGUCHI, Ryuji NISHIUCHI
1986 Volume 52 Issue 476 Pages
1177-1185
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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This paper presents expressions and computational graphs to determine the optimal tuning and damping parameters for a linear system with two degrees of freedem. The maFss m
1 is connected to an immovable foundation through a spring k
1 and a dashpot c
1. An impressed harmonic force acts on the mass m
2. Either of the masses (named main mass) should be isolated from the vibration originating from the impressed force ; whereas, the other mass functions as a dynamic absorber. The optimization criterion is minimizing the maximum displacement of the main mass. The optimal design parameters can be formulated when c
1=0. If c
1≠0, optimization is carried out using numerical analysis, such as the Newton-Laphson method. The optimal conditions obtained theoretically are summarized in graphs, and tested on a vibratory model. The experiment makes is clear that the theory is very useful for the isolation of actual mechanical vibrations.
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Shin TAKAHASHI, Katsuyoshi SUZUKI, Tadashi KOSAWADA
1986 Volume 52 Issue 476 Pages
1186-1191
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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A method is presented for solving free vibrations of conical shells with variable thickness. Three components of displacements are assumed to have quadratic expressions of thickness. The characteristic equations are solved by a new method. Frequencies and distributions of displacements and stresses are presented, and the former is compared with the Mirsky method and also a linear approximation method.
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Shinji HAYAMA, Masaaki MATSUMOTO
1986 Volume 52 Issue 476 Pages
1192-1197
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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The pressure pulsations in pipelines frequently generate severe vibrations in the piping systems. The exciting forces due to internal flow oscillations are analyzed. It is found that they are generated in the regions where the pipelines have static deflections or geometrical curves like bends, by reaction forces due to the acceleration of the fluid in the pipe and forces due to spatial momentum change ; and that the former have the same frequencies as those of the pressure pulsation, and the latter twice Unstable vibrations due to parametric excitation may occur when the fluid has a high density, or the pipe has a low buckling load. Experiments have confirmed the theoretical analyses.
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Hiroyuki KOJIMA, Hideo SHIRAISHI, Kosuke NAGAYA
1986 Volume 52 Issue 476 Pages
1198-1202
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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In this report, the transient vibrations of a beam mass system subjected to nonlinear electromagnetic force are investigated theoretically and experimentally in consideration of both the nonlinearity of the electromagnetic force and the inductance of a electromagnet. The beam is fixed at one end, and the mass is attached to another end. The electromagnetic force produced by the elctromagnet acts on the mass. The electromagnet is excited by sinusoidal waves, rectangular waves and rectangular pulse voltages by using a micro computer. In the analysis, the electromagnetic force is approximated by using a series of rectangular pulses, and the lateral vibrations of the beam are obtained by adding the individual responses due to each rectangular pulse. The response solution of the governing partial equation of the beam mass system is derived by the Laplace transformation method. The numerical results agree well with the experimenatal ones.
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Seiji CHONAN, Naotake NOZAWA
1986 Volume 52 Issue 476 Pages
1203-1210
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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This paper is a study of the dynamic response of an infinitely long thick strip plate subjected to an impulsive load. The plate is simply supported along the edges and resting on a viscoelastic foundation. The problem is studied on the basis of a plate theory, in which the effects of rotatory inertias and shear deformations are retained. Governing equations are solved by applying the methods of the Laplace transform with respect to time, and the Fourier transform with respect to a space variable. Dynamic coefficients (=maximum dynamic displacement / static displacement or maximum dynamic bending moment / static bending moment) are calculated numerically for plates subjected to a step line load, and shown graphically for various values of the parameters included.
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Katsuyoshi SUZUKI, Kuniaki SUGI, Tadashi KOSAWADA, Shin TAKAHASHI
1986 Volume 52 Issue 476 Pages
1211-1217
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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This paper is concerned with the dynamic response of a plane curved bar with varying cross-sections under a dynamic load working perpendicular to the plane comprizing the. center line. As numerical examples, time responses of displacement and bending moment are found for a symmetric semd-elliptic arc bar having varying cross-sections and clamped ends subjected to a step concentrated impact load. The behavior of responses due to variations of the cross-sections and the load point are clarified.
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Shinki OHTSU, Yoh KAWAKAMI, Kiyoshi KANEDA
1986 Volume 52 Issue 476 Pages
1218-1223
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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In the previous paper, a survey was reported on the vibrations of electrical concrete breakers, one of the typical piston-operated vibrating tools. From various analyses of vibration measurements, it was confirmed that the main cause of vibration sensitivity was the reaction force of the connecting rod via the piston, resulting from rapid air compression rather than the impingement of the chisel for the chisel holder on the front of tool. Based on such a conclusion, two kinds of system were adapted on the vibration reduction and vibration isolation of the breakers. One of them consists of the dynamic balancer driven by the positive cam, and the other consists of the elastic coupling between the crank shaft incorporated in the cylinder body and the motor section. The former was not always effective in reducing vibration in handles because of the restricted size and weight, but the latter was considerably effective in isolating vibration in handles, about 6∼10 dB smaller in vibration level than conventional ones.
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Takeshi FUJIKAWA, Masaru NITTA, Kozo OKITA, Fumiyasu KURATANI
1986 Volume 52 Issue 476 Pages
1224-1231
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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The authors attempt to construct a system with several degrees of freedom having the same modal parameters as those obtained by FEM analysis or measurement. In this paper, a system identification method using sensitivity analysis is proposed for an undamped lumped-mass model. In the method, model parameters such as mass values or spring constants are initially given and then modified by the least-squares minimization procedure to minimize the difference between the predicted modal parameters and the desired values. Some conditions on the selection of the model parameters and the desired values are discussed for obtaining the solution of system identification. System constructions, for example, with three or five degrees of freedom models are shown, thereby demon-strating typical characteristics of the presented method.
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Etsujiro IMANISHI, Takeshi FUJIKAWA, Yoshihiro HAMAZAKI, Hiroshi ZUI
1986 Volume 52 Issue 476 Pages
1232-1239
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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A new method is proposed for analyzing complex structures by a substructure synthesis method. In this method, mass and stiffness matrices of components are expressed by unconstrained modes, and can be applied for both theoretical and experimental modal analysis. Several numbers of the modal coordinates of each component are retransformed to the physical coordinates of the connection points by using normal mode shapes. Therefore, each component can be treated as one of the finite elements in FEM analysis, making it possible to connect them to each other or one another directly or to connect them with nonlinear elements obtained by FEM. A new technique is also proposed for correcting the truncation error of higher order modes by using dummy masses at the connection points. The dummy mass technique improves the dynamic characteristics of the total system without using the residual compliance matrix. The effectiveness of the procedures is demonatrated by numerical examples.
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Masaru NAGAIKE, Akio NAGAMATSU, Shinya KIJIMOTO
1986 Volume 52 Issue 476 Pages
1240-1247
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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The space distribution and frequency spectrum of the sound pressure and acoustic intensity emitted from the outer surface of an internal combustion engine are analyzed by both the boundary element method and the usual simple method. The experimental value of the vibrational velocity of the outer surface of the cylinder block when a piston head is excited is used as the input data of the above calculation. The sound pressure and acoustic intensity around the actual engine are measured by the vibration test when a piston head is excited with harmonic force under conditions of a nonreflective room. Accuracy of the calculated results, both by the boundary element method and by the usual simple method, are investigated by comparing them with the experimental results.
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Masaru NAGAIKE, Akio NAGAMATSU
1986 Volume 52 Issue 476 Pages
1248-1256
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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The vibration of an internal combustion engine is analyzed by the multiple component mode synthesis method (MCMS) proposed by the authors. An engine is regarded as a combined system of a piston, a connecting rod, a crank shaft, a flywheel and a cylinder block. First, the vibration of the crank shaft is analyzed independently by the component mode synthesis method. The crank shaft is divided into 20 components, the natural modes of all components calculated by the finite element method are composed to make the equation of motion in the modal coordinates, and the vibration of the crank shaft is analyzed with this equation. Next, the vibration of the cylinder block is analyzed independently by MCMS. Finally the vibration of the total structure of the engine is analyzed by MCMS. All calculated results agree well with the experimental ones.
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Yukio ISHIDA, Takashi IKEDA, Toshio YAMAMOTO
1986 Volume 52 Issue 476 Pages
1257-1264
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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This paper deals with subharmonic oscillations of the order 1/2 and some types of summed-and-differential harmonic oscillations in a symmetrical rotating shaft system with quartic nonlinear spring characteristics. It is known that the restoring force of the shaft has quartic nonlinearity intensively, in addition to quadratic and cubic ones when the shaft is supported by double-row angular contact ball bearings. It is clarified in this paper that the nonlinear terms of the fourth order have strong effects on these kinds of osillations which are caused by nonlinear terms up to the third power of coordinates. We theoretically analyzed these oscillations, paying attention to nonlinear components represented by the polar coordinates, and showed variations of the resonance curves and the occurrence of unstable vibrations. We also ascertained these phenomena in experiments.
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Atsuo SUEOKA, Takashi AYABE, Hideyuki TAMURA, Norihito YAMAMOTO
1986 Volume 52 Issue 476 Pages
1265-1271
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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The rolling noise arises from the interaction of the vibration characteristics between a rail and wheels through the contact points. This paper deals with the coupled vertical vibrations between a rail and a wheel, regarding the rail as an infinitely long Timoshenko beam installed on an elastic foundation and the wheel as a point mass. The authors analyse the linear and nonlinear vibrations due to the linear and nonlinear contact forces between the rail and the wheel, respectively, for the case that the wheel moves along the rail with a sinusoidal irregularity. The influences of several factors of the rail upon the coupled vibration characteristics are also examined. The random vibrations due to the irregularity of the rail are also discussed, and the importance is pointed out of not only the vibration at the contact point, but also the distributed one in the longitudinal direction of the rail.
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Hiroshi OTA, Kazuki MIZUTANI, Tadao KAWAI
1986 Volume 52 Issue 476 Pages
1272-1279
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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The approximation previously proposed by the authors is applied to an analysis of unstable vibrations of a rotating asymmetrical shaft supported by asymmetrically flexible bearing pedestals. A frequency equation is represented by the determinant of the 4th order, 8th order, or 12th order, according to three cases in which a directional inequality of bearing pedestal stiffness is negligibly small, small but considerable, or not small, respectively. Instability regions are obtained by solving each frequency equation. No matter what the magnitude of directional inequality of bearing pedestal stiffness may be, the position, width and number of instability regions can be sufficiently determined by use of the determinant of the 8th order. The same instability regions are obtained by calculation even though the determinant of the 12th order is used. Instability regions derived from approximation are found to agree well with those obtained by an analog computer.
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Yukio ISHIDA, Takashi IKEDA, Toshio YAMAMOTO
1986 Volume 52 Issue 476 Pages
1280-1288
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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This paper deals with subharmonic and ultra-subharmonic oscillations in a rotating shaft system with nonlinear spring characteristics involving quartic terms. When the shaft is supported by double-row angular contact ball bearings, nonlinear terms of the fourth order appear in the restoring force in addition to the second and the third terms. Owing to this quartic nonlinear component, subharmonic oscillations of the order 1/4 and ultra-subharmonic oscillations of the orders 3/2 and 2/3 will probably appear. We analyzed these oscillations theoretically paying attention to the nonlinear components represented by the polar coordinates and investigated the probability of occurrence and the shapes of the resonance curves. We also conducted experiments and compared their results with the theoretical ones.
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Yukio ISHIDA, Takashi IKEDA, Toshio YAMAMOTO, Hiroki OKADA
1986 Volume 52 Issue 476 Pages
1289-1296
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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This paper deals with summed-and-differential harmonic and super-summed-and-differential harmonic oscillations in a rotating shaft system which are caused by quartic nonlinearity. We theoretically analyze these oscillations, paying special attention to the nonlinear components represented by the polar coordinates. We clarify which kind of nonlinear component has an influence on each oscillation. In experiments, the shaft was supported by double-row angular contact ball bearings, and the restoring force had nonlinear spring characteristics involving quartic nonlinearity, in addition to quadratic and cubic ones. Experimental results were compared with the theoretical results regarding the probability of occurrence and the shape of the resonance curve. As the result, it has become clear that such analysis is very effective in predicting the occurrence of oscillations in a practical rotating shaft system.
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Nobuo TANAKA, Yoshihiro KIKUSHIMA
1986 Volume 52 Issue 476 Pages
1297-1305
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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From the viewpoint of feedforward control, this paper deals with an optimum design of a vibrationless forging hammer system presented in the previous paper. First, a chart to estimate the control effect in terms of a feedforward control is shown. Then, with the aid of the chart, a design procedure of the vibrationless forging hammer system is demonstarted. In order to design the control system quantitatively, a performance index to show the suppression effect of a transmitted impulsive force is proposed. Based upon the index, a nonlinear programming is applied to find optimum parameters of the system. Furthermore, taking into consideration a realizability of the feedforward element, the vibrationless system is designed. Finally, by using a signal wave of an impulsive force obtained in the actual impact process, a simulation experiment is carried out, and the capability of the vibrationless hammer system is verified.
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Nobuo TANAKA, Yoshihiro KIKUSHIMA
1986 Volume 52 Issue 476 Pages
1306-1311
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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In the previous papers, the principle of a vibrationless forging hammer was proposed, and optimum designed procedures of the feedforward control system were shown. The purpose of this paper is to realize the vibrationless system designed by the feedforward control method, and also to verify the capability of the system experimentally, First, before conducting the impact experiments of the system, this paper adopts a feedforward chart proposed by the authors to estimate the control effect as well as to obtain a perspective of the realizability of the control system. Then, from the viewpoint of an impact experiment, the control effect of suppressing the impulsive force is shown. Furthermore, it is demonstrated that both analytical and experimental results show a high degree of agreement. Finally, by changing impact conditions such as the height of a hammer head, impact numbers, etc., the robustness of the control system is shown.
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Keiji YOKOSE, Isao NOMOTO, Hiroshi SHINDOH
1986 Volume 52 Issue 476 Pages
1312-1320
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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In this paper, we analysed, ed theoretically the hunting stability of a bogie truck having a small clearance in the connecting position between the truck frame and the bolster anchor when the spring and friction are connected in series against truck turning. According to the theoretical analysis, we suggest that the exclusion of clearance is extremely important for securing the running stability of high speed railway vehicles, because the hunting velocity may be reduced due to the influence of clearance. Then, the fact that the limit cycle corresponding with the hunting velocity is an unstable limit cycle when there is no clearance is examined. However, on the contrary, there appears to be either a stable limit cycle or an unstable one corresponding to the magnitude of the angular amplitude of the truck frame if there is cleamance in the connecting position between the truck frame and bolster anchor. In the practical analysis, we investigated truck hunting which occurred in an actual car during a SHlNKANSEN running test carried out by the JNR.
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Osamu SATO, Hiroshi SHIMOJIMA, Akihiko SAITO, Tsuyoshi KANEKO
1986 Volume 52 Issue 476 Pages
1321-1328
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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Motion of a prismatic part, which rolls across a surface, is analyzed theoretically in consideration of stiffness and viscous damping about elastic deformation of the surface and edges of the part, and the motion is also investigated experimentally. The probability that the parts will come to rest in a particular natural resting aspect is derived in consideration of the dissipation of energy when the parts bounce up and down.
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Ryoichi ICHIMIYA, Wataru FUKAI
1986 Volume 52 Issue 476 Pages
1329-1336
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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It is important to make a precise estimation of the sound pressure level distribution in a factory which contains many noise sources, such as machine tools, oil pressure equipment, etc. The sound pressure level in the factory varies because the sound sources do not always generate constant sound pressure by repetition of the working and resting of the machine tools. This paper deals with the simulation of the sound pressure level in the factory, which is analyzed with sound energy equations and the Monte Carlo method. Effects of the room constant, working ratio, frequency, deviation of sound power level, etc., on the sound pressure level are made clear.
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Kohshi NISHIDA, Toshiaki YOSHII
1986 Volume 52 Issue 476 Pages
1337-1343
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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In this paper, the pressure wave form of the impact sound, which is radiated from the end surfaces of a ram in the deformation process of a billet, is discussed theoretically and experimentally. The impact sound may be attributed to air pulses caused by the sudden acceleration of the ram. The impact sound wave at a field point is calculated by superimposing those emitted from the divided small elementary areas of the end surfaces. In the calculation, it is assumed that the acceleration of the ram consists of a half sine pulse, and that the shelter effect due to the ram can be ignored when the wave length of the impact sound is larger than the dimensions of the ram. The superimposed sound pressure wave forms agree fairly well with those measured in the laboratory experiment, and show fairly well, the change of wave forms due to different points.
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Takahiro ITO, Takehiko FUJIOKA, Masakazu IGUCHI
1986 Volume 52 Issue 476 Pages
1344-1350
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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Before the slip of a driven wheel set occurs. The increase of torsional vibration of the axle can be observed. Perceiving this vibration. the slip can be predicted. To detect this vibration the force transducer's signal from the axle must be filtered in a band-pass filter, whose passing frequency band includes the natural frequency of the wheel set. A digital filter or analogue filter can beconsidered for this purpose. The advantage of digital filter is that the parameters can be easily changed by the alternation of the software and the filter calculation can be easily coupled with control calculation The problem is that all the calculation must be completed within the sampling interval. In this paper a digital filter for optimum adhesion control is proposed. The calculation time of the proposed filter is shorter than that of FFT method. Experiments confirmed that this digital filter can be used for optimum adhesion control.
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Masaya MURATA
1986 Volume 52 Issue 476 Pages
1351-1354
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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The Ladder Chart have been used to the presentation of programs on the Programable Sequence Controller (P.C.) as same as on the electric sequence circuits consisted of relaies. But, it is unsuitable method for the presentation of programs on P.C. because which involves new codes of micro computor never seen in sequnce circuits of relaies. The new description method using Boolean Algebra and the new symbols for new codes is prefered. This method gives a logical presentation and the convenience of progam coding.
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Hiromitsu HIKITA
1986 Volume 52 Issue 476 Pages
1355-1361
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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This paper concerns the decoupling of a linear right invertible system. The system structure of a decoupled system is investigated from the viewpoint of closed loop poles. It is also related with a compensator by a simple equation. The closed loop poles, therefore, can easily be assigned while preserving decoupling by adjusting the system structure; and the corresponding compensator is automatically determined. By taking account of the causality of the compensator, a new decoupling method is derived which simultaneously realises arbitrary pole assignment by a static or dynamic compensator.
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Katsunobu KONISHI, Kouji MAEGAWA, Toshio YOSHIMURA, Hirokazu ISHIHARA
1986 Volume 52 Issue 476 Pages
1362-1369
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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This paper is concerned with the model reference adaptive control (MRAC) of single-input single-output discrete-time linear systems subject to unknown constant and small vibrated disturvances. A method to decrease the input-sensitivity to the small vibrated disturvance is presented. The method consists of two steps : The extension of the controller structure of the basic MRAC so as to include enough parameters to adjust the transfer function between the input and the vibrated disturvance ; and the step to determine the parameters by using the 1st-order Butterworth low-pass filter or the quadratic criterion. Experimental results of a pressure control system show that the magnitude of the input vibration at the steady state is reduced to l/5∼1/6 of the basic MRAC, and that the control performance is comparable to the well-tuned velocity-type PI control.
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Naoto YANAGIHARA, Hiroshi SAITO
1986 Volume 52 Issue 476 Pages
1370-1374
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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The true value of impact force, in high speed deformation tests of metals, is commonly measured by the use of the Hopkinson-bar method. But, a defect of this method is the restriction of measurable time because of the length of the bar. One of the authors suggested constructing a measuring theory for impact force acting on a bar with uniform cross sectional area, based on the theory of the propagation of longitudinal elastic stress waves. From the stresses detected at two points on the bar, two stress waves travelling in opposite directions along the bar axis are separated, and the impact force is estimated, without the restriction of the measuring time. This paper presents a new theory for measuring the impact force which occurs on a bar having two different diameters. The results of the experiments clearly confirm the correctness and usefulness of this theory.
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Hiroomi MIYAGAWA, Keiji IMADO, Kazuaki KAWAKITA
1986 Volume 52 Issue 476 Pages
1375-1379
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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In recent years, a new measuring method utilizing the Hall effect for three dimensional ball motion has been developed. The reliability of the data was confirmed by comparing the data obtained by this new method with those obtained by the induction coil method. The components of the angular valocity of ball motion and the alteration of contact angle during one cage revolution were analyzed, based on the data by the new method, and the influences of race failure on ball motion under static moment loading were investigated.
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Keigo FUKUNAGA, Masafumi SAKAMOTO
1986 Volume 52 Issue 476 Pages
1380-1386
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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The oil-film-formation between gear teeth lubricated with grease or oil lubrication is investigated by the electrical resistance technique. The grease examined is a lithium soap structure in mineral oil. The properties of grease are very similar to those of oil material. Tests are made with pairs of 31 and 35-teeth spur gears of 2.5-module, 20 deg pressure angle, and l0-mm face width. The values of loading force are changed from P
n =66. 7 kN/m to 472 kN/m in steps and the values of pitch line velocity are also changed from V= 1.59 m/s to 6.19 m/s. The observations are as follows: (1) The volume resistivity of grease is measured. (2) The relationship between the passage of time and the oil-film-formation became clear. (3) The maximum load carring capacity with grease lubrication is about 60 per cent of that with oil lubrication.
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Fumio OBATA, Komei FUJITA, Masahiro FUJII
1986 Volume 52 Issue 476 Pages
1387-1393
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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As a basis for the study to clarify the relationship between scoring occurrence and temperature in spur gear pairs, the temperature rise in a rectangular shaped body used as a model of a gear tooth was examined analytically, when a moving heat source with variable heat quantity was supplied repeatedly at regular intervals. The characteristic of the temperature rise of the body and the effect of radiation on the temperature rise were investigated. The temperature rise on the working tooth flank in the heat supply region and its neighborhood can be divided into the flash temperature component not affected by the state of radiation and the bulk temperature rise component significantly affected by it.
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Akira YOSHIDA, Komei FUJITA, Kiichi MIYANISHI, Osamu TORII, Kenji HIGA ...
1986 Volume 52 Issue 476 Pages
1394-1401
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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In this report, the effects of hardened depth and relative radius of curvature on surface durability of a nitrided aluminium chromium molybdenum steel roller are experimentally elucidated. The experimental results are discussed by the amplitude of ratio of shear stress to Vickers hardness. The surface failure mode in this experiment was spalling due to the crack having its point of origin beneath the surface. The depth of the spalling crack agreed well with the depth of the maximum amplitude of the ratio of the orthogonal shear stress to Vickers hardness. The surfase durability of the nitrided roller tended to increase as the hardened depth increased and the relative radius of curvature decreased.
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Toshimi TOBE, Masana KATO, Katsumi INOUE
1986 Volume 52 Issue 476 Pages
1402-1410
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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The residual stress of carburized spur gears is calculated being based on the assumption that the main cause of residual stress is the volume difference between case and core due to the martensitic transformation in cooling. The relation between hardness and carbon content is determined for SCM420H test gears by the measurement, and is used to estimate the specific volumes of the structures from the distribution of hardness. The two-dimensional FEM is used for the calculation The reliability of the method is examined by comparison with stresses measured by the X-ray diffraction method. The present method is then applied to the estimation of residual stress of carburized gears whose hardness and retained austenite are recommended in the AGMA standard. A formula is proposed to estimate the residual stress from hardness and the amount of retained austenite, and it is applied to the estimation of the fatigue strength of carburized spur gear teeth.
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Shoji HAIZUKA, Chotaro NARUSE, Ryozo NEMOTO
1986 Volume 52 Issue 476 Pages
1411-1419
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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Recently, one of the most important problems is in measuring the efficiency of gears and, further, in finding the way how to increase their efficiency. This problem has already been studied, but the final detailed conclusions have not yet been published. In our study, several factors for increasing the efficiency of gears, i.e. factors for decreasing the frictional loss of gears, were investigated. It was found that by means of increasing the viscosity of base oils and concentration of anti-wear additive plus EP additive to the base oil, we can obtain only very low effects on the decrement of frictional loss. On the contrary, however, synthetic oils bring about quite remarkable effects on the decrement of frictional loss. Further, the temperature rise in gear teeth was measured in connection with the frictional loss and a relationship was found between them.
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Aizoh KUBO, Satoshi KIYONO, Makoto FUJINO
1986 Volume 52 Issue 476 Pages
1420-1425
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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A new method to analyze or predict the state of machine vibration owing to gear meshing is introduced. Most of the results of research on gear vibration published until now dealt with only very simple vibrational systems of a pair of gears. But for common gearing or machines with gears, the vibrational system is much more complicated, and direct application of these results is impossible. This report shows one new method to analyze such a complex system; that is, a method to reduce a forced vibrational system with parametric exciting terms into quasi-equivalent forced vibrational system without a parametric exciting term. Using this method, the vibrational exciting force due to gear manufacturing and alignment error and to periodical change of tooth mesh rigidity are integrated into one total vibrational exciting force E
v which acts at tooth meshing position. Using of E
v, the machine vibration owing to gear meshing can be analyzed by conventional methods of vibration analysis for systems without parametric excitation.
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Atsunobu MORI, Shigemitsu KIMURA, Haruo MORI
1986 Volume 52 Issue 476 Pages
1426-1434
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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This paper describes the observation of physical aspects of cavitation and film pressure profiles in a circumferentially grooved journal bearing subjected to rotating loads. Photographic evidence is presented to illustrate how the patterns of the cavity and pressure profile change in accordance with the combination of the rotation and precession of the journal. The correspondence of the pressure profile to the pattern of the cavity is discussed qualitatively through the flow field. This is related to the boundary conditions for the Reynolds equation. For particular cases without journal rotation, there can be found a pressure gradient in the fernlike or scaly cavity, which renders conventional cavitation models useless. A compressible full film model is proposed, and its feasibility is examined.
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Yoshio HARUYAMA, Tsuneji KAZAMAKI, Haruo MORI, Shin-ichi YOSHIZAWA
1986 Volume 52 Issue 476 Pages
1435-1441
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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The exact solutions for the squeeze film flow of an incompressible Newtonian fluid and that of a gas between circular parallel surfaces are presented under the assumption of a small sinusoidal vibration. From a comparison of the conventional approximate solutions with the exact one and the experiment, it is concluded that the averaging approach in which the inertia term is averaged out across the film thickness gives fairly good approximations, and that the perturbation solution becomes remarkably inaccurate as the unsteadiness becomes high.
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Yoshio HARUYAMA, Tsuneji KAZAMAKI, Astunobu MORI, Haruo MORI
1986 Volume 52 Issue 476 Pages
1442-1447
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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In this report, the authors investigated theoretically and experimentally the inertia effects on the dynamic performance of externally pressurized circular thrust bearings in a turbulent flow regime within a capillary restrictor. From the experiment, it is concluded that the influence of turbulence should be considerable when the Reynolds number decreases in value, and that the presented analysis yields good predictions for the dynamic bearing performance for a wide range of the Reynolds number.
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Tamotsu NAKAMURA, Haruki IMAIZUMI, Katsuo KATAYAMA
1986 Volume 52 Issue 476 Pages
1448-1454
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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It has been suggested, on the basis of experimental results, that a surface roughening phenomenon would be generated as a result of relative differences of an amount of deformation in thickness size due to random orientations of crystallic grains in the sub-surface layer. A simulative analysis of surface roughening has been carried out using a theory of the plasticity of crystals, on the basis of a constant uni- axial tensile stress model of F. C. C. structure polycrystalline aggregate. It has been confirmed that the surface roughness and wavelength of the surface profiles simulated are qualitatively similar to the experimental results.
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Toshiyuki SAWA, Akihiro KARASAWA, Youichi HARADA, Akihiro SHIMIZU
1986 Volume 52 Issue 476 Pages
1455-1461
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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The design method of bolted joints with gaskets is almost based on experience, and the sealing performance is not made clear by theoretical analyses. In the present paper, discussion is made on the distribution of contact stress in the bolted joints fastened with tap bolts, when a clamped part with a gasket is the cover of a pressure vessel and a circular flange. The distribution of contact stress is analyzed as a three-body contact problem, using the three dimensional theory of elasticity. Moreover, the contact stress is measured by means of ultrasonic-waves. In addition, the force ratio (the ratio of an increment of the bolt axial force to an external load) and the maximum stress caused in bolts taking account of a bending moment are analyzed. For verification, experiments are carried out, and the analytical results are in fairly good agreement with the experimental ones.
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Takeo SHINMURA, Eiju HATANO, Koya TAKAZAWA
1986 Volume 52 Issue 476 Pages
1462-1468
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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This paper describes the magnetic-abrasive finishing process, and its trial equipment, in which the cylindrical workpiece is finished with the assistance of a rotating magnetic field using mechanical bonded magnetic-abrasives made of both iron and alumina particles. From the experimental results, it is found that the finishing efficiency is improved and the finished surface roughness value is a little large in the case of the rotating magnetic field compared with the stationary magnetic field. In this report, which combines the rotating magnetic field with the stationary magnetic field, a new efficient finishing process is developed and confirmed by experiments.
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Shinsuke AKAGI, Ryohei YOKOYAMA, Koichi ITO
1986 Volume 52 Issue 476 Pages
1469-1476
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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The objective of this paper is to develop an optimal planning method for the initial design of an energy supply plant of an LNG carrier. With the objective of minimizing the total annual cost, both the scales and numbers of various equipment of the above plant are investigated in order to be planned optimally together with operational policies for several energy demands of steam, electric power and propulsion. This planning problem is first formulated as a mixed-integer linear programming one, by adopting zero-one integer variables indicating the equipment's selection or the on/off status of operation together with continuous variables indicating the operational level of each equipment. Then, the optimal selection and operational policies of the equipment are determined numerically by adopting the branch and bound algorithm. Lastly, the effectiveness of the planning method proposed here is ascertained through a numerical study for an energy supply plant of actual scale.
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Yoshiyuki NAKAGAWA, Toshio YOSHIMURA, Katsunobu KONISHI
1986 Volume 52 Issue 476 Pages
1477-1482
Published: April 25, 1986
Released on J-STAGE: February 21, 2008
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In this paper, geometric modelling is discussed to represent free-form curves and surfaces for computer-aided design systems using the B-spline. The B-spline is convenient to use for interactive design, and has no specific geometric restrictions to represent complicated curves and surfaces with a small number of points. The number of knots is reduced by the condition that the distance between a given curve and an approximate representation exists within a prescribed tolerance. The placement of knots is found interactively using an approach that concentrates the knots in the region of the large curvature. The smoothing of surfaces is performed by the identity condition of curvature derivatives on both sides of the knot point vector. The proposed methods are applied to the geometric modelling of a turbine blade, and the numerical results illustrate the superiority of the proposed methods.
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