The present study discusses better solutions, as an extension of the previous paper in which the existence of the solution in terms of an elliptic function and three algorithms to obtain the modulus parameter by the trial scheme were proposed. For a quasi-linear case, the modulus is now solved explicitly in terms of the given frequency by using the reversion of power series. For strongly nonlinear case, an algorithm for a high speed trial solution is developed to determine the Fourier characteristic parameter by applying the so-called q-expansion theory. The application also makes it possible to treat the ultra low frequency range for which no usually available formulae overcome the computer difficulty. The numerical results are demonstrated, in which in particular the solutions composed of the pulse train for the strongly nonlinear slow vibration are included. Results due to five different methods are mutually compared to estimate their respective accuracy / optimal territories in the frequency region.

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In previous papers, the authors presented a new technique of identifying a nonlinear multi-degree-of-freedom vibratory system and showed its applicability by numerical simulation. To see how an actual vibratory system is identified by the presented technique, an identification system is developed based on the technique and using a personal computer, and is applied to some simple vibratory systems. The identification results is then evaluated by comparing the actual response of the vibratory systems with the predicted response using the identified parameters. It is shown in this way that the developed technique can well be used for identifying the vibratory systems in a reasonable time.

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The authors propose a method of direct identification of design parameters (mass, location of the center of gravity, the moment of inertia, spring constant, damping constant and the location of the support of elastic mounts) of a damped vibration system of rigid and elastic mounts. In this method, modal parameters are repeatedly modified by changing the design parameters based on the sensitivity analysis of the complex eigen value in order to correspond to the objective values (damped natural frequency, modal damping ratio, mode shape coefficients). A calculation model and a rigid body model are examined to verify the usefulness of the method.

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An earthquake and microtremor isolation floor system is developed for high-tech facilities such as computer rooms, VLSI factories and those manufacturing lasertechnology-applied products. The system consists of 3-dimensional isolators, air dampers, viscous dampers and leveling controllers which automatically maintain the level of the floor. The 3-dimensional isolator, which is made from the compound construction of an air spring and a laminated rubber bearing, absorbs vertical vibration by the air spring, which the horizontal one is primarily by the laminated rubber bearing. To examine the effectiveness of the system, seismic shaking tests and microtremulous tests of a floor model weighing 20 tons were performed. The results are satisfactory and the effective isolation of both earthquakes and microtremors is confirmed. It is observed that the numerical predictions are in good agreement with the experiment results.

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The influences of the internal resonance on the subharmonic oscillation [3p₂] and the superharmonic oscillations [p₁/2], [p₁/3], [p₂/3] in a nonlinear two-degree-of-freedom system whose natural frequencies, p₁ and p₂ are at the ratio of 1:2 are discussed. By the theoretical analysis, we clarified the following : (a) The kinds of nonlinear terms which have an influence through the internal resonance are different among these nonlinear forced oscillations. (b) In the cases of the oscillations [3p₂] and [p₂/3], the stationary solutions where two modes coexist appear in addition to those which appear in the system with no internal resonance. The resonance curves of the former bifurcate from those of the latter. (c) In the cases of the oscillation [p₁/2] and [p₁/3], the other mode always appears, and only the solutions where two modes coexist appear. (d) Almost periodic oscillations are not obtained in every oscillation.

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The impact vibrations of grouped bars between restraints caused by excitations such as earthquakes are studied by shaking table experiments. In this report, the frequencies at which jump phenomena occur (jump frequencies) are considered. The parameters relating to jump frequencies are derived, and shaking table experiments are performed on these parameters. The experimental results show that jump frequencies are not influenced by the impact stiffness and the number of bars, but are influenced by the parameters relating to the nondimensional input parameter such as the position of the impact springs, the total gap and the input acceleration. The analytical results using the single-degree-of-freedom model introduced by the observed phenomena are in good agreement with the experimental ones assuming a proper value of the coefficient of restitution.

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To monitor the shaft vibration of a rotary machine, the rotating pulse signal and the shaft vibration signal are detected by one vibration sensor, and vibration data is derived from this measured result by data processing. The vibration wave is analyzed, and the characteristics of the shaft vibration are gained. This method is applied to a measurement of the shaft vibration of a vertical-type rotary machine. A method by which the position of a rotor on a vertical direction is gained, is shown. This method is applied to a rotary machine. From the measurement of the position of the rotor on the vertical direction, the state of the rotor and the variance of the bearing gap according to the rotation are known in the rotation. By use of this result, we can monitor the magnitude of the abrasion of the bearing.

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Theoretical analyses are presented for the dynamic stability of a free-clamped coaxial cylindrical shell partially filled in the annular gap with incompressible, inviscid liquid and subjected to vertical excitation. The dynamic version of the Donnell equations and the velocity potential theory are used for the motions of the shell and the liquid, respectively. The problem is solved by using the modified Galerkin method so as to satisfy the boundary conditions, and the governing equation is reduced to a type of coupled Mathieu's equation. The instability boundaries where parametric resonance occurs are determined by using Hsu's method. It is found that a principal instability resonance and a combination instability resonance of the sum type of two natural vibrations, each of which has the same circumferential wave number and different axial mode of vibration, are likely to occur. Further, the interactive effect of the coaxial cylinders is found to become small with an increase in the wave number and the annular gap.

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Vibration analysis of thick rotating cylindrical shells subjected to an initial torque is described. The basic equations, including the effects of the initial tensions and resultant shear stresses due to rotation, torque, external pressure and axial compression load, are derived by the Timoshenko-type shell theory. By the modified Galerkin's method, frequency analysis is carried out for four boundary conditions (i.e., both ends (A) clamped with axial constraint. (B) Simply supported without axial constraint. (C) Simply supported with axial constraint and (D) clamped without axial constraint). Numerical results are compared with those based on the Flugge-type shell theory and the difference between both thoeries is examined.

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For the purpose of decreasing the lower critical speed of circular cylindrical shells, which are used in centrifugal separators to enrich uranium, and rotating at higher speeds, it is considered that circular cylindrical shells are connected with bellows. Vibration analysis of circular cylindrical shells connected with bellows is carried out by the substructure synthesis method for various numbers and dispositions of bellows, and the optimum ones are examined. Moreover, the transfer matrix method, by which the critical speeds are simply obtained, is described and the results are examined by the substructure synthesis method.

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In the previous report, a method of vibration analysis of continuous bodies was presented. This method is based on the transfomation of analytical solutions into discrete relations between displacements and concentrated forces at nodal points located on part of the boundary of a subdomain. The resulting relations have the same forms as those in the FEM. In this paper, transient pressure responses of fluids contained in rigid pipes of which cross sections varying along axes are calculated by the method. The calculated results of the time history of pressure change agree well with the experimental results. This means that the accuracy of calculation is sufficient for higher modes of natural vibrations of the systems. The present method is also effective in shortening the computational time.

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In a piping system driven by two compressors having the same rotating speed and an arbitrary crank phase angle, the magnitudes of the pulsation responses are affected by the crank phase angle between them. Thus, in a pulsation analysis, it is necessary to develop an effective and conservative technique to estimate the maximum response in the design stage. In this paper, three conventional methods are discussed and a new method is proposed : their accuracy and usefulness are examined through a numerical pulsation analysis by a finite element method for some typical models. It is found that the present method is sufficiently accurate and is useful for practical applications.

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In a piping system including a reciprocating compressor, pulsating flow would be generated by intermittent injection from the reciprocating compressor. When the pulsating flow is in a condition of resonance, it would naturally result in an undesirable variety of problems. In this paper, a new method for the attenuation of the pulsation is reported. The new method consists of side-branch pipes in which fibrous matters or many orifices having large openings are packed. The side branch pipes have large and uniform resistance against the pulsation and increase the damping of the piping system. The new method shows good performance and is effective even when the operating conditions change. It does not increase the power consumption of the compressors because it has not resistance in the path of main flow.

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Stability of a viscous liquid layer of horizontally infinite extent, on the bottom of which a liquid saturated porous plate is set, is studied theoretically and experimentally under a vertical oscillation. The theoretical analysis is carried out under the assumption that the system is most strongly excited by the 1/2 subharmonic response. The neutral stability curves are found theoretically in the plane of the frequency-amplitude of the applied force. On the other hand, the experiment is undertaken by using the aqueous glycerin and the porous plate of the sponge rubber. From the theoretical and experimental results, it is found that if a porous plate is set on the bottom of the liquid layer at a constant total depth, the system is stabilized, and if the solid bottom of the liquid layer is replaced with a porous one at a constant depth of the liquid layer, it is also stabilized. Thus, in any case, the system is stabilized by the presence of a porous plate.

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Many vibration problems of combustion engines have been resolved supported by the progress of experimental measurement and computor-aided engineering systems. Dynamic theories of the piston-crank mechanisms still consist of the static equivalent mass and correcting crank torque methods. They have been called the approximate analysis because they are predicated on the constant angular velocity about the crank axis. This paper discusses the basic relationships of the reciprocating engine dynamics in order to verify these conventional methods. The results are that some of them are correct and another is not sufficient for analyzing vibration, on the angular accerelation of the crank shaft.

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Eliminating brake squeal generated during brake application is an important subject for the improvement of comfort in a car. There has been a lot of research into the problem of brake squeal in the past. Most of the papers presented elaborate on low-frequency brake squeal. However, brake squeal often has high-frequency vibration. For this reason, we have researched high-frequency brake squeal (5-10 kHz), so as to study the method of eliminating brake squeal by modification of the brake disc.

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The resistance against truck turning, that is composed of the friction force and elastic one working in series, contributes to the running stability of bogie-cars. So, up to present, the effects of the resistance have been studied as to the stability for hunting motion. But this study deals with its effects on the forced lateral vibration caused by the alignment irregularity of track. The numerical integration of motion equations by Runge-Kutta-Gill method is applied for the analysis. As the 1st report, this paper describes simulated results about effects of the friction force at side bearer in relation to the amplitude of track irregularity and running speed. These results suggest that it is disadvantage to the running vibration to lower the friction coefficient of side bearer from the present value as a countermeasure against the heavy wear of wheel-flange.

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The 1st report showed that contact loss and stress of a contact wire of the existing system were too large for the satisfactory current collection at a speed of 300km/h. In order to improve the situation, the effect of the parameters on the performance are studied using the same equipment. Tension and mass of contact wire and mass and upward force of the pantograph are changed. And a test is also done under the condition that the wave propagating velocity of contact wire is lower than the pantograph velocity. The experimental results as well as theoretical analyses indicate that contact loss and nondimensional stress of contact wire depend mainly on the wave propagating velocity of contact wire and the contribution of pantograph mass to the improvement is smaller than that of this velocity.

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This paper deals with a small creature recognition and identification method by using image processing based on expert systems for the application of the micromanipulator system. Since creatures under the microscope are not all the same, moving and changing forms and shapes with time, in the normal pattern matching method used for industrial products, conventional methods cannot be applied. This newly proposed method is based on the segmentation method of creatures, consisting of characteristic features independent of the individual size and length : complicated images of creatures are divided by the segments into simple shape segments such as line, circle, oval and others. The connection between the segments is described by the expert system. Then creatures are expressed simply by the set of these segments. Tracking a specific creature by image is also shown in this paper. Thus, the method can avoid the individual differences of creatures. The effectiveness of this method is shown with some experimental results.

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The VSS design problem for a linear system has been investigated using a quadratic performance index, the value of which can be more lowered by logically switching admissible gains {K₀, K₁, ..., K_p} than by the single gain K₀. The VSS control law is characterized a gain-switching surface for a quadratic function of the state and by including a design parameter α. Furthermore, the concept of the resultant model is introduced with a view to inspecting the VSS performance as a parameter of α. Practical application to a servo-system composed of a DC servomotor (50W) and gears is made with the result that the proposed VSS is more effective in the improvement of the index than the single gain K₀ feedback system.

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A systematic synthesis of planar mechanisms is carried out with consideration of the tolerances of pairing elements. Namely, optimum tolerances of holes and shafts which make pairs in the mechanisms are determined using a probability density function, for the purpose of reducing the output errors of oscillating links in the mechanisms. Based on the above analytical results, the optimum tolerances of pairing elements of planar six-link mechanisms are arranged, as a practical example of multi-link mechanisms. As a result, it has been revealed that the maximum output errors are reduced up to approximately half the level of those of mechanisms which have the same clearance at every pair.

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In this paper, fatigue tests using high-hardened compact tension (CT) specimens with heat treatment are carried out. CT specimens are of finished machining and rough machining. Their surface roughness of the notch root is about R_max = 2-11 μm. The CT specimens are of a 0.45% C steel, the hardeness 53 to 56 H_RC, and the root radii for the notch is 5 mm. The results may be summarized as follows : (1) Fatigue life is equal to the number of cycles until failure. (2) Fatigue life is independent of the surface roughness of the notch root. (3) Fatigue limit is 502 to 525 N/mm², that is, about 1.24 times that of AGMA.

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This paper presents a study on the root stresses of thin-rimmed spur gears due to press-fitting. The stress analysis of the thin-rimmed spur gear press-fitted upon the shaft or the bush by the 2-dimensional finite element method (FEM), in which the elastic contact between the thin-rimmed gear and the shaft or the bush, was taken into consideration, was carried out, and the root stresses were measured. The effects of rim and bush thicknesses, number of teeth, and interference on the root stress and the stresses at the contacting surface were examined. On the basis of these calculated results, a practical formula for the maximum true root stress of thin-rimmed spur gear press-fitted upon the shaft was derived.

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A method for calculating the tooth profile of a WN (Haseg SymMarC) gear, generated with a hob, is indicated, and a mapping function for the profile approximated to the tooth profile of a WN gear is obtained. The true root stresses of a WN gear calculated by the 2-dimensional elasticity theory and mapping function are compared with those by the 2-dimensional finite element method (FEM), and the validity of the root stress analysis of a WN gear by the theory of elasticity is confirmed; the position of the critical section on tensile and compressive sides of a WN gear is clarified. The stress concentration factors at the position of the critical section are calculated under different loading conditions. A practical formula for true root stress of a WN gear is derived on the basis of these calculated results.

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The use of gears for power transmission is conditioned by the strength as well as the accuracy. The employment of austempered ductile iron is examined from this view point. The test gears are made of ductile irons FCD45 and FCD60. They are austenized at 900°C then austempered at 300 to 400°C. In the austempering process, the bainitic transformation causes size expansion and a considerable tooth profile error of the gears. The profile error can be reduced by austempering at 400°C or employing the ferrite-bainite dual phase ductile iron. The bending fatigue tests are performed by using electro hydraulic servo controlled pulsators, and SN curves are obtained. The higher the austempering temperature, the higher the fatigue strength. The fatigue strength of gears austempered at 400°C is about 520MPa and it is higher than the strength of normalized S45C gears.

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Usually, the conditions of finished tooth surfaces are different between a pair of pinion and gear of the medium-hardness gears (the hardened and tempered gears), because their sizes, materials and hardness are often different each other. The authors investigate the influence of roughness combination of a pair of gears on their surface durability using a disk machine with rolling and sliding. The first report deals with the case of the same hardness combination, and the results are summarized as follows : (i) The pairs of disks with the combination of the surface roughness 10 μm and 1 μm R_max have the pitting limits of about 0.26 HB kgf/mm², while the pitting limit of disk pairs with 10 μm R_max is about 0.1 HB kgf/mm². (ii) However, the disk with smooth surface (1 μm R_max) is worn out considerably, and further the pits of the lower speed disk with smooth surface occur earlier than those of the higher speed one with rough surface. (iii) When a pinion with smooth surface mates with a gear with rough surface, the above facts indicate that the pitting and wear resistances of pinion should be made higher than that of gear.

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The tooth bearing of a bevel gear is easily changed by assembly errors, because both shafts of a bevel gear pair are not parallel. In the present paper, under conditions in which a test bevel gear was assembled with a complete tooth bearing a toe tooth bearing or heel tooth bearing the dynamic behavior of the skew bevel gear was investigated under various gear operating conditions using a power circulating-type bevel gear testing machine. By measuring the tooth root stresses, the vibrating displacements in three directions perpendicularly intersected each other on a skew bevel gear. In comparison with these measured data, the effect of the tooth bearing on the dynamic behavior of a skew bevel gear is clasified.

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To find out a fundamental tooth profile design policy for the scoring of spur gears, the effects of tooth profiles on scoring behavior were examined taking account of the two-cylinder test results. The tip interference on the approach side markedly affects the scoring phenomena. Both the reduction of the maximum specific sliding on the geometrical working flanks and the avoidance of tip interference on the approach side are the essential conditions to obtain spur gears having superior scoring load capacity. In the mixed lubrication state, where the scoring occurrence has an intimate relation with the working flank bulk temperature, the scoring bulk temperature of a spur gear pair with no tip interference on the approach side can be estimated well by the bulk temperature on the outer surface of the cylinder immediately before seizure in two-cylinder tests.

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In the previous paper it was shown that the ring-shaped spur gear can be formed by successive indentation of a rack-shaped punch. A ring-shaped specimen is deformed by the flow of the indented material in the circumferential direction working in this method, causing changes pitches of the formed grooves. The specimen is observed experimentally to be deformed with a similar pattern throughout working. A deformation model of the specimens is proposed using an elastic-plastic finite element method to simulate well the actual deformation behavior. Spur gears with a maximum accumulated pitch error of 0.3 mm are produced by indentation of a rack-shaped punch with pitches determined theoretically based on this deformation model.

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Determination of the errors of hobs and a hobbing machine is necessary in order to improve the hobbing accuracy. This paper focuses on the configurations remaining on the tooth surfaces of hobbed gears, and clarifies analytically the tooth surface configurations affected by the errors of hobs and the hobbing machine. The errors of concern are lead variation and eccentricity, while the errors of the hobbing machine are the change of the revolutionary center and the rotational irregularity of the table. From the relationships between the surface configurations and the errors of hobs and the hobbing machine, it is possible to estimate the errors by the observation of the tooth surface configurations.

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The feed marks on the tooth surfaces of hobbed gears express the characteristics of the tooth surfaces very well, and are related closely to the errors of hobs and hobbing machines. In this paper, the formation mechanism of feed marks caused by the errors of hobs and hobbing machines is investigated, and the relationships between the errors and the feed marks in the tooth surface configurations shown in the first report are clarified. Moreover, the relations between the feed marks and calculated tooth profile errors are investigated. From those relationships, it is possible to estimate the errors of hobs and the hobbing machine by the feed marks of hobbed gears.

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The hourglass-shaped worm wheel is often cut by a fly tool, especially in the case of small production or of large size. The previous report has taken a NC technique into the fly tool method, and the tool is controlled to trace the theoretical wheel tooth surface. With this method, several traces of the cutter are needed to envelop a theoretical surface, and this results in low productivity. In this paper, the NC fly tool method is combined with conventional technique such as the tool edge profile and the cutter position selectings almost suitable to the wheel tooth surface. In this method, an edged cutter traces the wheel tooth surface one time only. The tooth surface profile errors are investigated in the case of the Lorenz method, the NC Lorenz method and the tilted axis NC fly tool method. The latter method has the potential to reduce profile errors by several percent of those of the first two method.

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The so-called fly tool method of cutting hourglass shaped worm wheels offers an economical production of large-size worm gears. This method however, gives us only an approximate tooth surface of the wheel. The previous reports introduced the numerical control (NC) technique to the fly tool method for making a tool which is able to trace the wheel surface. The fly tool method demands high responsibility of the NC servo to obtain a high cutting speed. To prevent the speed problem, this report discusses two methods of end milling : (1) the end mill tool is driven as the tool of the fly tool method, and (2) the tool is fed in the orthogonal three directions. The tooth profile errors of wheels cut with these two methods are investigated. Compared to the latter method, the first method gives a higher precision of profile, but it is difficult to realize the motion of the tool. A bronze wheel is cut for a trial with the latter method, and the tooth bearing pattern is checked. A method of tooth surface modification is proposed.

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The plastic gears used for driving paper-drying drums in paper-making machines and others are used at a gear ratio of 1:1 by putting several gears in a row. Accordingly, the intermediate gears undergo loading on both tooth surfaces, but at present, the operational characteristics of the plastic gears being used in this way have not been elucidated at all. Therefore, in this study, the operation test applying alternating loads was carried out using MC nylon gears and such things as the operational term of life, the wear of teeth, and the state of change of tooth profile were examined.

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The changes in head geometry caused by head-and-tape contact are investigated experimentally and analytically. Dummy heads made of copper and lapping tapes are used for wear tests in which the dummy head slides on the lapping tape travelling under constant tape tension and sliding velocities, leading to a constant contact force. An optical interference microscope and a surface profilometer are used to examined the head geometries, and an optical microscope is used to examine the head-and-tape contact area. The tape deformation is calculated using the finite element method under a condition of uniform pressure applied to the tape. From these investigations, the following is clarified. At the early stage of wear, the head wears selectively where the contact force is high. The head reaches specific geometries in spite of the difference in initial geometries of heads. This means that the contact pressure between the head and tape becomes uniform in accordance with the progress of wear. The head geometry in a steady state of wear is very close to the tape deformation calculated under uniform pressure. This result shows the occurrence of uniform wear, and the wear volume V calculated by V = cPvt, where c is the specific wear rate, P is the contact force, ν is the sliding velocity and t is the sliding period.

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Using a replication technique, we examined the tribological morphology of carbon sputter-coated thin film disks during overload and contact-start-stop (CSS) tests. The main results are as follows : (1) The replicated profiles on acetate replicas were successfully observed by a scanning electron microscope (SEM) using secondary electrons. The SEM image analysis can determine the wear asperity of a dimension of 60 nm. (2) Disk durability in the overload test depended on carbon layer thicknesses. More than 20 nm thickness was necessary for the sufficiently high durability. (3) In the CSS test on a 5nm-carbon-thickness disk, a surface scratch of a dimension of 1 μm width and 0.1 μm depth was induced even by the initial 4 CSS cycles.

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In this second paper, the influence of inlet pressure boundary conditions on the static characteristics of sector-shaped pad thrust bearings, which are subjected to the effects of both turbulence and fluid inertia forces, is investigated theoretically and experimentally. The basic lubrication equations presented in the first paper are solved by a numerical technique combining the control volume integration and the Newton-Raphson iteration method under the three kinds of inlet boundary conditions in accordance with three types of lubrication conditions. The theoretical results pertaining to the pressure distribution, load carrying capacity and center of pressure are obtained for θ=60°, R₁=0.5, A=1.0-2.0, Re=2 000 and R^*_e=0-1.6, and the results of the load carrying capacity are compared with the experimental results. From these theoretical and experimental results, the relationships between the inlet boundary conditions and the static characteristics of sector-shaped pad turbulent thrust bearings are clarified.

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A new type of self-controlled restrictor using a floating disk is proposed to obtain a very high stiffness in a hydrostatic bearing. This new type restrictor can control the mass flow rate of an operating fluid by using only a balance of the forces exerted on both sides of the disk in contrast with a conventional diaphragm-type self-controlled restrictor which uses an elastic deformation of a diaphragm. Here, the static characteristics of a hydrostatic thrust bearing with this new type restrictor are theoretically and experimentally investigated. It was shown that the hydrostatic thrust bearing has a very high stiffness (nearly infinite stiffness) in a very wide range of imposed load.

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The linear stiffness and damping coefficients of a fluid film in a seal clearance are theoretically investigated in the laminar regime. In this study, the porous materials are applied to the annular plain seals employed in the pumps by insertion into the inlet part of the seal. The modified Reynolds equation, including a so-called filter term, and the pressure equation obtained from Darcy's law, are applied to the system and are numerically solved. Under the same conditions, the annular plain seals with the porous materials have larger main stiffness terms and cross-coupled damping terms, and smaller cross-coupled stiffness terms, in which the K_XY is smaller in magnitude, and smaller main damping terms than those of the ordinary ones with the solid surface. Furthermore, with increasing the axial length of the porous material applied to the seal surface, the main stiffness terms increase in the range of the smaller axial length than the total one of the seal surface, while the cross-coupled stiffness terms and the main damping terms decrease.

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This paper deals with the characteristics of bolted joints under thermal changes. When a bolted joint in which the coefficient of linear expansion of bolts is less than that of clamped parts is put under thermal changes, the bolt axial force produced in the bolt and the compression between the clamped parts are increased with an increase of temperature. The variations of the bolt axial force and the compression between the clamped parts are analyzed during an increase of temperature, and a formula to obtain these variations is proposed. In the experiments, strain gauges for high temperature are glued to the shank of the bolt made of steel and the outer circumference of the clamped parts made of aluminium. When a bolted joint is put in a furnace, the strains of the bolt and the clamped parts are measured during an increase of temperature. The numerical results are in fairly good agreement with the experimental results.

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A diamond grinding wheel is generally used to grind hard and brittle materials, such as advanced ceramics. It is however, quite difficult to dress a diamond grinding wheel efficiently because of its high degree of hardness. In this study, some investigations are carried out to increase dressing efficiency of resinoid bonded diamond grinding wheel. Dressing forces are measured over a wide range of dressing conditions, and SEM observation of a grinding wheel is carried out. Special attention is paid to comparison between stick method and rotary brake method. Results obtained in this study provide useful information for determining required dressing time, and for choosing efficient dressing condition for diamond grinding wheels.

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The press-forming tests of the precipitate-hardening aluminum sheets, A 6061, were conducted under various preaging, quenching and full annealing conditions, as the preliminary test of the thermomechanical treatment to determine the coexistence of the strengthening of the sheet and the improvement of the press-formability. The main results are summarized as follows : (1) The stress-strain relations of the materials in which the precipitation has not yet developed follow the saturated law. Consequently, this characteristic must be taken into account in evaluating the press-formability, a new factor of ductility n^* is proposed. (2) The n^* is appropriate in the evaluation of the stretchability of any aluminum ally sheet containing the materials tested so far. (3) Deep-drawability, using the hemispherical punch, correlates n^* under the consideration of r. (4) For deep-drawability, using the flat-headed punch, n^* is the indicator of sudden change, and r is the main factor.

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In order to estimate the number of roll passes necessary to form the light guage steels for general structure, the relation between the shape factor and the number of roll passes for various sections is investigated by arranging the data collected from several companies. We can obtain a good correlation for symmetrical, asymmetrical and wide profile section. Furthermore, allotment of roll bend angle at any stage was carried out under the hypothesis that the locus of the edge of the section on the horizontal plane was modified by the cubic curve. The roll flower for sash section, track sections, keystone plate, deck plate and pipes designed by this CAD system agreed well with actual roll drawings.

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The performance of dispatching rules is usually tested under various criteria. When due-date criteria are applied, dispatching rules that consider the shop state usually give good results. In this research, the discussion in concentrated on the due-date performance aspect of dispatching rules. Based on an analysis of the relations between the primary factors which affect the due-date performance, a shop state dependent switching rule is proposed. The rule is tested against some other due-date oriented rules under seven kinds of due-date based criteria and is found to be superior to the other rules. Focusing on mean tardiness criterion, further comparison is made with varying degrees of due-date tightness and shop load heaviness, and the proposed rule exhibits obviously better performance than the others.

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A completely separated functional FMS (flexible manufacturing systems), or a partly separated functional FMS, should be constructed because a fully functional FMS, where each machine has all of the tools required for processing various kinds of jobs, is superfluous and wasteful in meeting the multiform and changeable demands of consumers in a flexible manner. A series of the effective methods are presented in this study for allocating the tools to each machine in a 2-machine flowshop type FMS to meet the above demands and to maximize the utilization of the FMS. The method for a completely separated functional FMS having no duplicated tools is proposed in this report. Some simulation results clarify that the utilization of the FMS by this method is as high as the fully functional FMS when the number of jobs is large, but is less than that when the number of jobs is small, especially in the case that a distribution of job operations is exponentially biased.

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A method for distributing tools to each machine in a 2-machine flowshop type FMS with some duplicated tools (a partly separated functional FMS), is proposed in this report. This method is composed of three parts : one for selecting duplicated tools, one for allocating unduplicated tools, and one for allocating job operations processed by these duplicated tools to one of the machines having these duplicated tools. Maximum I and II are proposed for selecting the duplicated tools. The method for allocating tools proposed in the first report is used for allocating the unduplicated tools. A heuristic method of exchanging some pairs of job operations processed by the duplicated tools is developed for allocating job operations to each machine. Some simulation results show that the proposed method is effective for increasing the utilization of the FMS.

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This tool attempts to be able to deal, in practice, with all phases of design processes from the conceptual design to the drafting, and with a wide implementation to design of various kinds of machinery. The tool evolvs so as to be that which (1) a user can interact with an actual configuration of image revealed on the display at an early step of the conceptual design, and (2) is easy to amend the shape partially and recalculate accordingly by a provision of the back-tracking feature of the tool. A STANDARD-CONFIGURATION slot is added to the frames in the knowledge base, which participates in cooperation with the existing ELEMENTS-VECTOR and HOW-TO-DESIGN slots in the way that the STANDARD-CONFIGURATION slot will proceed to get an organic relationship between concept and shape, while the last two slots can deal with the control of design procedures.

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This paper concerns the development of any curved surface using dynamic programming. In the case of designing curved transformation of any arbitrary region on the curved surface into flattened forms are indispensable to manufacturing processes. Generally speaking, until now, as there is no systematical sheme to get flattened forms, methods by man require a lot of effort. We have already proposed a method to transform any curved surface using the finite element method. In this paper, we introduce ideas of the dynamic programming to the primal problem. That is, an objective curved surface is decomposed into the regions in juxtaposed strips. Then each region is developed into a flattened shape. The whole shape is derived by means of solving multistage decision processes. To illustlate the results, we apply them to transform duct and shoe models into flattened forms.

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