The deformation and strength of single lap joins having different thicknesses of adherends were investigated both analytically and experimentally. The strain distributions of the joints of carbon steel bonded with epoxy resin under tensile shear loading were analyzed by the finite element method. The strength of the joints was predicted by applying the strength laws for adherend, adhesive layer and their interfaces to the calculated stress distributions. The calculated strain distributions in the joints were in good agreement with the experimental observations. The predicted strengths of the joints were close to the measured values by experiments. On the basis of the results obtained, the effect of the adherend thickness on the joint strength is discussed.

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The problem of an elastic infinite body containing a series of spherical cavities under tension is treated. It is assumed that several spherical cavities with equal radii are arranged on a line at equal intervals and that the infinite body is subjected to uniform tensile stress in the direction of the line of cavities. The method used in this study is a numerical one in which the general solution of the biharmonic equation in the polar coordinates is recurrently superposed until all boundary conditions at the surface of each cavity are satisfied. Calculated results for the stress concentration factor are indicated in some diagrams for various values of the number of cavities, the ratio between their interval and radius, and Poisson's ratio.

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This paper deals with the interaction between a thin elastic stiffener of finite length and an internal crack in an anisotropic half space under longitudinal shear. The problem is solved by the singular point method. Replacing the crack and the stiffener with continuous distributions of screw dislocations and concentrated forces, respectively, we obtain a set of singular integral equations. In order to clarify the influences of anisotropy of the matrix, physical properties of the stiffener, and the geometrical parameters of crack arrangement on the stress intensity factor at the tips of the crack, numerical calculations were performed. The results are shown in figures.

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The size effect on the crack growth in SUS 316 steel was studied by observations of load-displacement curves of many proportional compact specimens with various nominal widths. When the thickness was less than 0.2 times the width, the critical crack-tip opening-displacement (CTOD) for the start of steady crack growth was proportional to the thickness. The proportional constant was expressed by the experimental constants (yield stress, work-hardening parameters and fracture true stress) obtained by the unidirectional tensile tests. It was concluded that a ductile crack grows when the normal stress ahead of the crack-tip exceeds the fracture true stress of the materials.

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We have measured the tensile fracture properties of the TiC coated SUS316L stainless steel, applying a stress perpendicular to the plane of interface between the coating and the substrate. The fracture of the as grown or non-an-nealed specimens occurred partially within the TiC layer. A tensile fracture of the TiC coated specimens after vacuum annealing at about 1373K(1100°C) presented arc-shape curved fracture surfaces which can be understood by statics consideration taking into account the maximum stress plane theory and the residual thermal stress. The strengths of non-annealed and annealed specimens are 34.4MPa(350kgf/cm²) and 30.2MPa(308kgf/cm²), respectively, expressed in terms of Weibull's 50% fracture stresses.

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This paper presents an exact solution for the transient response in the interior of an elastic half space subjected to a normal or a tangential semi-infinite line load varying with time as a Heaviside unit step function on its surface. The solution is based on the stress function approach, the Laplace transform and the double Fourier transform method applied to a non-axisymmetric dynamical problem. The Laplace inverse transform which is performed by the three-dimensional Cagniard's technique gives an exact solution for the stress wave propagations. The results of numerical evaluation are shown graphically for the stress variation versus time in the interior of a half space.

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The propagation of transient waves in an elastic half space excited by a normal or tangential impulsive loading over one quarter of its surface is investigated. The solution is based on the stress function approach and the Laplace transform, the double Fourier transform method to non-axisymmetric dynamical problem. When the Laplace inverse transform is performed by means of Cagniard's method, it is important whether the formulation has, or has not, singularities on the real axis of Fourier transform plane. The stress transient in load region was compared with that on free surface. The numerical results are shown graphically for the stress variations versus time.

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Incompressible potential flow through a cascade of staggered thin airfoils with steady loading in general, unsteady, in-phase motion is considered. With the assumptions of the Kutta condition and linearized wakes, exact analytical expressions are derived for pressure distribution, lift and moment, using conformal mapping applied to the velocity field. Mean attack angle and parabolic camber are considerd to give steady loading, and then the results are expressed in closed-form as quadratures, and reduce to the well-known relations for thin airfoil theory, as the solidity decreases to zero. Typical results are given in the figures. They should serve as a measure of the accuracy of numerical or approximate solutions, as well as representing in a simple way the effects of steady loading, stagger and solidity on unsteady cascade aerodynamics.

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Experiments on the behaviour of turbulent slugs and relaminarization in pulsatile flows are made using four ducts with different aspect ratios. When acceleration is relatively low, the propagation characteristics of a slug is qualitatively similar to that of a steady duct flow. For example, the propagation speed of the leading edge of the slug is larger than that of the trailing edge. In such a case relaminarization of low is controlled mainly by viscous dissipation. Meanwhile, when acceleration is relatively high, the disappearance and the following appearance of turbulent slugs are seen at fixed phases in a cycle and these phases hardly change in the downstream direction. This phenomenon is not inferable from the knowledge of steady duct flows. The relaminarization under the influence of such an acceleration is controlled mainly by acceleration itself and the limit under which relaminarization occurs is described by an acceleration parameter k first introduced about steady accelerating boundary layer flows. Its critical value agrees well with that obtained for steady accelerating flows.

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Using an abrupt stall type airfoil, which shows the nature of abrupt change in the static moment curve as the increment of angles of attack due to the sudden change of separation pattern to the leading edge separation, are investigated experimentally the unsteady aerodynamic characteristics of the airfoil in pitching oscillation near stall angle of attack. The aspects of the change of separation pattern during oscillation in this region of angle of attack are clarified in detail. The effects of mean angle of attack, reduced frequency, amplitude of pitching oscillation and location of pitching axis on the unsteady stall characteristics are made clear, and the region corresponding to separation patterns are defined.

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Helical surface instability of a cylindrical liquid jet in a cocurrent uniform gas stream was investigated theoretically and experimentally. The results according to the linear instability theory showed that a nonaxisymmetric wave disturbance could grow enough for a large relative velocity between the liquid jet and the gas stream. When the relative velocity became larger than a specified value, the shape of the liquid jet changed from "axisymmetric mode" to "helical mode". A helical disturbance on the liquid surface grew over the down-ward liquid column and broke up into droplets. About the frequency of the helical disturbance, the theoretical results agreed well with the experimental results. It was also found that the helical disturbance relates closely to the fluid flow conditions.

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When a flow with swirling component is introduced into a conical diffuser, the swirl center deviates from the diffuser axis and whirls around it if the swirl intensity and Reynolds number exceed critical values. The critical swirl intensity Ω_cr and the Reynolds number Re_cr depend on the diffuser geometry, especially on the opening angle but not on the area ratio. A nondimensional whirling frequency f^* depends on the swirl intensity and the diffuser opening angle but not on Reynolds number. The value of f^* becomes minimum at Ω=0.45.

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Fully developed incompressible turbulent flow in a conical diffuser with a perforated plate has been simulated numerically. A k-ε mode, which consists of two transport equations for turbulence energy and energy dissipation rate besides the mean velocity equation was applied, and a unique mathematical model was proposed to describe the effect of a perforated plate. Time-averaged distributions of velocities and pressures, and RMS values of turbulence are calculated in the whole flow region. The calculation results show that the diffuser efficiency and the uniformity of velocity distribution depend on the resistance coefficient K and location x_p of the perforated plate. The optimum combination between K and x_p is obtained for the high diffuser efficiency or the uniform velocity distribution. The Reynolds number is set at 2×10⁵ and 2000 grid points are distributed. Calculations were carried out on the FACOM/M 180 system in the Institute of Industrial Science, University of Tokyo.

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Dynamic characteristics of a bypass type flowmeter in pulsating flow and in transient flow were studied analytically and experimentally. (1) Parameters which influence measurement errors of the mean flow rate of pulsating flow with the bypass type flowmeter were clarified. (2) Depending on the configuration of the bypass passage, there were cases where the measured value of mean flow rate was larger than the true value and where it was less; a suitable configuration of the bypass passage should be used, to obtain a value that is close to the true one. (3) Parameters which influence response of the flow in the byapss passage during accelerating or decelerating flow were clarified.

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The purpose of this investigation is to make clear fundamental characteristics of convension performance of kinetic energy of a two-phase flow into work. As the first step, and experimental study of power generation by a Pelton-type turbine was conducted using an air-water two-phase mixture as the working fluid. The characteristics of the output and the efficiency for air and water flow rates were investigated. The efficiency was expressed as a function of the void fraction α and the flow pattern as follows : α<0.84 (bubbly flow) : η_max=0.75-0.20α α>0.84 (annular-mist flow) : η_max=2.5-2.3α The water flow rate ranged from 0.167 to 2.2 kg/s, the air flow rate from 0 to 17×10^-3 kg/s, and the output frm 0 to 280 W.

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Shaft displacement due to dump casing deformation which occurs when external piping forces and moments are applied was investigated. The test pump was an axially split, single-stage double suction volute type with foot support. An analysis by FEM(MSC/NASTRAN) was performed and considerable good agreement was obtained with actual measurement. It was found that shaft displacement due to pump casing deformation can not be neglected for pumps with foot support. In API 610-6th standard, limit of shaft displacement is 0.127 mm for pumps which have suction bores 300 mm or less. But according to this investigation, it is reasonable with pumps having suction bore diameters larger than 300 mm to enlarge this limitation. Effects of pump size and casing thickness on shaft displacement were investigated by FEM. The possibility of a galling of the casing wearing ring and a considerable leakage from mechanical seal caused by piping loads was also investigated.

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This paper presents a simple formula for thermal designing of natural-air-cooled electronic equipment casings with standard arrangement of circuit boards and power supplies. The formula meets the requirements as a practical formula, since it represents an air-cooling system in its simplified form with due regard to such factors as the stack effect, air flow resistance, natural convective transfer and so on. The formula was applied to predict the temperature rise in two practically used electronic equipment cabinets with standard arrangements and a modeling case. The predicted temperature rise values, obtained through the formula, slightly differed - within 10 percent - from the actual values based upon experiment results.

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To measure air excess ratio in exhaust gas, sensors are used which measure oxygen concentration in the gas by using a solid oxide electrolyte with a gas diffusion layer. In this paper, the movement of oxygen in the gas diffusion layer by solid oxide electrolyte is simulated with Nelnst's equation for solid oxide electrolyte and a diffusion equation for the gas diffusion layer. The calculated current value at the solid oxide electrolyte changes with the oxygen concentration distribution in the gas diffusion layer and agrees with the experimental value. Furthermore, it is affected by the thickness of the diffusion layer.

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This paper describes heat transfer studies in nucleate boiling of polyolester oil and freon R113 binary mixtures done to obtain design data on heat transfer performance characteristics of an evaporator. Pool boiling experiments were performed around horizontal straight heater pin at atmospheric pressure, heat flux was changed from 0 to 70 kW/m², and mixture oil concentrations from 0 to 100 weight %. These data were compared with published studies on oil-freon binary mixtures. The oil concentration influenced the heat transfer coefficient of oil-freon R113 mixtures ; with lage oil concentrations, a remarkable reduction in heat transfer occurred. Then based on the data, an empirical correlation for the heat transfer coefficient of oil-freon R113 mixtures was obtained. The correlation included terms for wall superheating of freon R113, oil temperature difference, and oil mole fraction. Comparisons were made between experimental and calculated results. The proposed correlation was found valid for the prediction of heat transfer coefficients of oil-freon R113 mixtures.

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This paper presents a numerical method for the three dimensional analysis of gas flow in boiler furnaces. This method is based on the Modified FLIC Method, which is a kind of finite volume method, and on the anisotropic porous media modeling tube bundles. Two application examples are shown in this paper. The first example is of an experimental model boiler furnace, and the calculated results show a good agreement with experimental data. The other example is of an actual boiler furnace. In the latter example, three dimensional gas flow characteristics in furnace and the rectifying effect of panelled tubes at furnace outlet on a flow pattern are discussed.

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This paper presents an experimental study on the phenomena of evaporation and ignition of a fuel-droplet impinging upon a hot surface. The experiment was made on seven kinds of fuels. It was revealed that cool flame is generated in n-heptane and diethyl-ether at a surface temperature range which is 300-400 K below that of hot flame generation. The surface temperature at which the cool and hot flames were generated was determined by applying a statistic method. Their delay times were also measured and then classified into physical and chemical delays by applying the statistic technique which was presented by Kumagai et al. The natures of both the cool and hot flame generation and the ignition temperatures measured by using the crucible method was discussed.

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The soluble and insoluble particles produced in heating the hydrocabon fuel have been measured to study the sooting processes. It is shown that soluble particles called presoot in this paper can be regarded as the "precursors", composed of heavy hydrocarbon droplets, and insoluble ones are composed of soot. Methane, propane, ethylene, and acetylene were employed as the fuel. As to the methane, propane, and ethylene, it is shown that presoot are produced in endothermic reactions and the overall activation energies are detemined from the Arrhenius plots of yields. In the case of acetylene, the reaction of soot formation is exothermic and presoot is not observed, because it grows into soot as soon as it forms by self-generating heat. Furthermore, it is shown that the effects of oxygen on both the presoot and soot formations are hardly detected and that the effective factors of fuel property are both the C/H ratio and the enthalpy of formation.

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Local soot particle size in a flame is often measured by light scattering methods, which are hampered not only by low signal-to-noise ratio but also by a limited knowledge on refractive index. In the present study, a laser homodyne method was applied to determine the size and number density by detecting Brownian motions of particles. For processing the signal, a photoelectron correlation method was employed using a fast digital correlator. The particle size and the number density could be successfully determined by the correlation time and the count ratio of signal photocurrent pulse to total one, respectively. This method was applied to laminar diffusion flames on a Bunsen burner, and the spatial distributions of particle sizes and number densities were measured. A discussion is made of the possibility of detecting the polydispersity from the obtained correlogram.

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An experiment on the mixing characteristics of the combustion gas in a two-dimensional test room which is a model of a marine boiler with ceiling burners has been carried out in the range of the inlet Reynolds NOs.=5x10³-3x10⁴. It was shown that the mixing characteristics in the combustion chamber were improved with an increase of flow resistance by the tube bundle and the concentration of the room, c^^-_L at the mean residence time, t_s depends on only the resistance coefficient of bundle c_f. The nondimensional concentration normalized by the inlet concentration c_o was expressed by the following empirical formula. (c^^-_L/c_o)_t=ts=0.62c_f^0.03

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The lateral oscillation of a simple levitated body, which is guided by magnetic forces, is examined theoretically and experimentally. Considering the relative vertical motion between the body and the magnetic guides, an ordinary nonlinear differential equation with periodic variable coefficients, which governs lateral oscillations of a simple levitated body, is derived. It is solved by use of the method of multiple scales with respect to time. As the main result, the condition of passing through the parametric resonance, is discussed in the case of primary resonance. It is also shown that a forced oscillation due to the unsymmetry of magnetic guide forces occurs at the same time in the case of secondary parametric resonance. Furthermore, the transient phenomena of passing through the primary resonance have been observed with a simple experimental apparatus. The steady-state oscillations under the combined influence of parametric and external excitations, have been observed in the secondary resonance.

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This paper describes the results of analytical and experimental investigations of the nonlinear harmonic and parametric resonance phenomena of a roller chain stretched vertically which is regarded as a system with many degrees of freedom, when the elongation of the chain during vibration is taken into account. The resonance treated in this report is one of the resonances excited under combined forcing and parametric excitations in which the ratio of the forced lateral displacement acting at a lower end to that of the tension fluctuation is 1:2. Two chains with different frictional coefficients were used in experiments in order to examine the effect of friction upon the vibration characteristics. The experimental results showed remarkable features attributable to the combined excitations and agreed well with the analytical results.

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In this paper, the effects of the torsional moment on the free transverse vibration of circular bars are investigated with the condition that the axial elongation can be neglected. A differential equation on the non-planar motion of the bar is derived. Then the equation is solved by means of the perturbation method and the numerical one for the case in which both ends are clamped. The results show that the characteristic frequency decreases quadratically with an increase of the torsional momet, which is contrary to the case of tension. It is also confirmed that the non-planar vibration arises due to the torsional moment.

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Rolling noise arises from the vibration due to the interaction between wheels and rail through the contact points. The authors treated the vibration of a rail in the horizontal and vertical directions in the previous papers. In this report, the axial vibration of a rotating wheel, at the circumference of which shear force and spin moment from kalker's linear creep theory act simultaneously, is formulated in order to consider the coupled vibration between wheels and rail in the horizontal direction. It is shown that the response of the steady-state vibration is obtained by solving the simultaneous algebraic equations with respect to the contact forces. As a verification of the present analytical method, the theoretical and experimental impedance characteristics of a stationary wheel suspended with springs at a point on the outer circumference are compared.

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This paper deals theoretically and experimentally with the forced oscillation in the vicinity of the dynamic unstable region of an unsymmetrical rotor system having nonlinear spring characteristics due to ball bearings. Near this rotating speed of a shaft, an unstable region vanishes and a stable oscillation appears due to the nonlinearity. We discussed this oscillation with attention to the nonlinear components represented by the polar coordinates and clarified which component has influence on this oscillation. Since this system involves an external force due to the unbalance, nonlinearity and the characteristic of parametric resonance, we have investigated the effect of the coexistence of these factors on the vibratory phenomena. We have also compared this oscillation with the super-summed-and-differential harmonic oscillations in a symmetrical shaft system and the dynamic unstable vibration of an unsymmetrical rotor system reported previously.

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Flexible solar battery paddles of spacecrafts have low frequency vibrational characteristics due to the stringent limitation of the weight of launched rockets. The basic problem dealt with here is how to estimate and control the vibrational modes of flexible booms of the arrays even in large angle attitude maneuvers. First a proposed mode estimation method with use of outputs of solar cells is shown to give good estimation of the vibrational modes. Then, it is shown that even static output maximization control in a desired direction cannot work stably without flexibility control based on the mode estimation and that the boom is controlled dynamically based on the feedback control theory so as to suppress the vibration of the arrays even in large angle attitude maneuvers.

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The use of digital control techniques for active magnetic bearings has, in comparison with analogue controls, the following advantages : (1) more simplified hardware for the electric circuit (2) universality of electrical hardware (3) more sophisticated control techniques are applicable (4) software flexibility (5) extension of the system using additional CPU. Using a simple experimental apparatus of vertical single axis control, digital controls with a microcomputer were tested together with the analogue technique, as a first step to multi-axes control with high speed rotation. In impulse tests the digital control was almost equal in performance to the analogue control. Especially, the first-order digital PID control gave satisfactory results. However, noise of half the sampling frequency is amplified and harms control performance in some cases.

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For saving energy and resources, the spheroidal graphite cast iron is tentatively used as gear material. It has many advantages in manufacturing and physical properties. The authors apply this material to medium-hardness gears which are used in medium or large size gear units. First, new materials--3 kinds of JIS FCD60 by various heat treatments and as-cast FCD70--are produced by way of trial. From the machinability tests of these materials by turning, it is clear that the as-cast FCD70 has the best machinability in terms of cutting force and tool life. Second, the hobbing surface roughness to hardened and tempered steel. Third, the surface durability of as-cast FCD70 is investigated by using a 2 roller-type contact fatigue testing machine. It indicates that the pitting fatigue life of the as-cast FCD70 is longer than that of hardened and tempered steel. Consequently, the as-cast FCD70 is applicable to medium-hardness gears in terms of manufacturing and surface durability.

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In order to elucidate the effect of case depth on fatigue strength and failure of case-hardened gears, fatigue tests were performed using a power circulating gear testing machine. Case-hardened gears with three different case depths including an optimum case depth for surface durability which was determined by a calculating method derived from roller tests were used in the tests. It was revealed that the type of tooth breakage caused by bending fatigue or surface fatigue depended upon the case depth and that the above mentioned calculating of optimum case depth was valid also in gear design.

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To determine the scoring resistance of spur gears with various coatings, scoring tests on gear pairs coated with copper, graphite, molybdenum disulfide and phosphate were carried out under forced lubrication using a power-circulating gear machine. Further, the surface temperature of a coated gear tooth was calculated. From the experimental results it was found that the effect of copper and molybdenum disulfide on the scoring resistance of the gears was significant and gears, of which the load-carrying capacity with no scoring was considerably large, could be developed. The order of the calculated surface temperature for scoring of the gears agrees with that of the scoring resistance of the gears.

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This paper presents a study on dynamic behavior of thin-rimmed spur gears with various web arrangements. Natural frequencies of flexural vibration of gear body were measured and compared with the calculated results by Mindlin's method. The relations between these natural frequencies and the spectra of circumferential, radial and axial vibrations were investigated. The circumferential, radial and axial vibration accelerations and root stresses were measured under different running conditions by using a gear testing machine of power absorbing type. On the basis of these results the effects of web arrangements on vibration and dynamic load were clarified to a considerable extent.

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The life of plastic gears is shortened when they are used at a high temperature because they become less strong and vary in the way they mesh with each other, causing them to be worn away at their root in an abnormal way. It is necessary for lengthening the life of plastic gears to take care not to generate heat in them and to keep them from rising in temperature due to radiating heat quickly. The present report deals with various methods designed for lengthening the life of plastic gears having form and dimensions adapted to given operating conditions and makes inquiries about whether the use of these methods can lengthen the life of plastic gears to a greater extent than expected at the time of designing.

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Plastic gears have many merits ; silent running, self-lubrication, corrosion-proof, etc ; but they have many demerits too ; lower load-carrying capacity, lower-thermal resistance, etc. Because the plastic is expensive, the plastic gears should be designed as small as possible. Then, plastic gears which have smaller module, pressure angle of 14.5°, contact ratio above two and helical trace are proposed in order to increase economically their load capacities. The load capacity of a gear pair whose bending strengths are balanced by applying thick teeth to the plastic gear and thin teeth to the steel gear is double that of the usual gear pair having the same thick teeth.

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The Michell viscometer is mainly composed of a cup and a ball. The viscosity is indicated by the time, during which the ball adheres to the cup against the gravity, after the space between them has been filled with oil sample and the ball has been pressed against the cup firmly. Although the mechanism of this viscometer is very simple and the viscosity can be measured using only several drops of the sample, it has not been used widely. The authors have improved this viscometer in several points and developed a constant temperature box for it. As a result, the reliability of the measurement has become higher and the operation of the viscometer easier. For example, we can know numerically the relation between the distance covered and the kinematic viscosity of automotive engine oil without any difficulties.

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Mechanical behaviors of a hollow-bolt are analysed by a finite element method (FEM) which can deal with the contact conditions of threaded portions correctly. The characteristics of the load of No.1 thread, which is the nearest one to the bearing surface of a nut, and the stress concentration at the root of No.1 thread of a bolt are discussed by varying the inside diameter of a hollow-bolt, the friction coefficient at pressure flank and the nominal diameter. The results obtained indicate that the values of the load of No.1 thread and the stress concentration factor show opposite features to the variations of the inside diameter and the nominal diameter. Therefore, the evaluations of strength of a hollow-bolt based on the load distribution are not always correct.

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For carburized spur gears of m = 5 which have effective case depths d_eff = 0.6, 0.9 and 1.3 mm as well as non-carburized gears and normalized gears, relations between the residual stress at the root and the hardness are made clear. Bending fatigue tests are carried out to obtain SN-curves of these gears. The effect of case depth on the fatigue limit is not very significant. Influences of the residual stress at the root surface, the surface hardness and the core hardness on the fatigue limit are quantitatively determined from the results of fatigue test and a formula which may be available to estimate the fatigue limit of spur gears is finally proposed as a function of these factors.

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In designing bolted joints, it is important to discuss a clamping effect (contact stress distribution) and to estimate the force ratio (the ratio of an increment of bolt axial force to an external load). In order to improve the clamping effect, raised faces of the interfaces have been used. But theoretical grounds are not made clear. No investigations on the case where an external bending moment is applied to bolted joints are made either except some ones reported. In this paper, the clamping effect and the force ratio in the cases where T-flanges of which interfaces have non-contracted parts are subjected to external bending moments are analyzed using the two-dimensional theory of elasticity and the point-matching method. For verification, experiments are carried out with respect to the contact stress distribution and the force ratio for the external bending moment. Analytical results are in a fairly good agreement with experimental ones.

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Using a drop hammer apparatus, four kinds of impact compression and forming tests are carried out with nonmetallic materials (i.e., clay, plasticine, silicone polymer and rubber) which have various viscous/elastic/plastic characteristics, and their applicability to the new forming process previously proposed by the authors is discussed. It is concluded that a viscous medium with a high strain rate sensitivity m is advantageous for piercing and shallow stretch-forming. Some new applications (i.e., piercing of small holes and glass sheets) are presented.

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As a basic study for the establishment of the methodology for computer aided or automated design of machine structures, this report deals with a method of graphical description of the functional structures of power transmitting or motion transmitting machines, such as machine tools, measuring apparatus, etc. The machines are considered as an aggregation of motion transmitting elements, such as gear mechanism, screw driving mechanism, cam mechanism, etc. and their functional structures are graphically described using these elements. In this topological graph, the nodes correspond to motion transmitting elements and the edges correspond to relations between two elements such as fixed or motion transmitting. In addition, two fundamental motions, which are the input and output motions of the element are attached to each node. A gear shaper is selected as an example of graphical description of machine structure, and its fundamental motion graph and basic graph are presented.

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An aim of the investigation is to take on an intelligent aspect of CAD (ICAD) for the mechanical design through all processes from concept to detail even though the proposition of design is input semantically. First report as a preliminary study is, however, limited to only the conceptual design and for the case of a simple object which has relatively low degree of freedom. ICAD in this report has been carried out by means of applying the so-called frame representation and production rules by which knowledge and controlling rules are activated. As an actual example a coupling has been designed, and in that process, the design should be convergent and should have a unique solution no matter where the design is started inside the set which has the common top concept, for this instance, "torque transmission between shafts."

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