In this paper, using a differential equation of a cylindrical shell introduced by one of the authors, the deformation and strength of a cylindrical shell with cut-outs are discussed for the so-called exact solution. These problems have been discussed up to the present day by others. Their treatments, however, are performed under various restrictions with respect to the shape, size and the number of the cut-outs. The method of analysis proposed by the present authors has no such restrictions and is available for all the cases irrespective of the shape, size and the number of the cut-outs. As an example, a thin cylindrical shell having one large circular cut-outs under a uniformly distributed axial tensile force is analyzed.

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In this paper, a cylindrical shell with simply supported ends subjected to a concentrated twisting couple on its middle surface is discussed. A theoretical solution is obtained from the strict consideration of the properties of singularities in the cylindrical shell under the action of two types of concentrated loads, that is, circumferential and axial ones. Numerical results are presented for shells of radius to thickness ratios of 50, 100, 150 and 200 with a length to radius ratio of 4. They show that the radial displacement and bending stresses which do not exist in the case of the two-dimensional problem of elasticity appear owing to the existence of the curvature of the cylindrical shell. And also they are not so small as we expected and become large as the ratio radius/thickness increases.

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From our experiments carried out about the bending and torsional fatigue of S35C specimens with a diametrical hole (each specimen has a round hole or its connected holes), the following results were obtained. 1) In the case of a specimen with a diametrical hole, the root radius of the notch at the branch point is constant (ρ₀&cong;0.5 mm in our material), as in the case of the bending fatigue test of the circumferential notched specimen. This means that the fatigue limit of the material with defects is mainly determined by the limit stress for propagation of its non-propagating crack. 2) when the fatigue limit of a specimen with a diametrical hole is determined by the crack strength (whenρ<ρ₀), the fatigue limit is mainly dominated by the diametrical hole in the perpendicular direction of the maximum tensile stress. This means that the fatigue limit of a material with defects is more influenced by the size of defect than by the sharpness of defect. 3) It is case of a plain specimen, τ_w/σ_w&cong;0.6; but in the case of the specimen with a diametrical hole, τ_w/σ_w=0.750.9. This shows that the effect of defect in the bending fatigue is greater than in the torsional fatigue.

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In the present paper, the wedge action of oil in the fatigue crack is calculated by using a simple crack model. The wedge action affects the propagation of fatigue crack on account of the viscosity of the oil and also of the repeated velocity of applied stress and it is more effective under smaller stress amplitude. To confirm the effects of the wedge action, fatigue tests are carried out on bearing metals lining on steel plates in pure mineral oil and in an oil with oleic acid under various stress frequencies. In pure oil, the experimental results are found to agree considerably well with the results of calculation. In an activated oil, however, the frequency effects on the crack rate decrease due to the reduction of wedge action on account of the crack width enlarged by corrosion.

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The paper deals with the flexural vibrations of a ring with arbitrary cross section and proposes an approximate theory to predict the natural frequencies by means of the Ritz's method. The frequency determinant is derived from the Hamiltonian principle by use of the stress-strain-displacement relations of three-dimensional theory of elasticity, and by expanding three components of the displacement in a finite double power series of the radial and axial coordinates with unknown coefficients. Compared with the experimental results for twenty three kinds of rings which are classified into six sets with respect to the cross section, the theory was ascertained to be available for the practical use. Furthermore, as an application to a general axi-symmetric elastic solid with free boundary surface, the frequencies of truncated conical shells and combined shells of hemispherical and circular cylindrical shells were calculated and compared with the already-known results, showing a good agreement between them.

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The authers developed miniature gauges for soil, grains and powders mentioned below:(a) Pressure cell: measuring the normal stress between grains and wall. (b) Friction cell: measuring the tangential stress between grains and wall. (c) Internal stress cell: measuring the magnitude and direction of principal stress in grains. (d) Gradient cell: measuring the angle of revolution in grains. (e) Strain cell: measuring the strain in grains. In these gages, (a)(d) are made up of electrical strain gauges, and (e) is made up of electrical coil. Then, using these gauges, the experiment of compression of sand in a cylinder was carried out. In this experiment, the accuracy of gauges was confirmed. And the distributions of resultant stress of wall, and internal stress and strain in sand were revealed.

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In order to obtain the blade characteristics of an axial fan with an orifice-type fan guide, the influence of the fan guide on the blade characteristics is investigated by establishing a theoretical model in which a flat plate parallel to the wing surface is placed near its tip. As the result, a Prandtl-type integral equation for this wing model is derived. In the present paper, the equation is solved when the wing and the plate are in the same plane. Furthermore, the wing planform and its aerodynamic forces satisfying the condition of minimum induced drag are also presented. Thus, the fundamental blade characteristics is clarified concretely.

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Using five comparatively simple shape converging- diverging nozzles which have been installed in the low pressure side of a shock tube, the transient flows induced in the nozzles by the impinging of the shock front have been observed optically by the schlieren method. Moreover, the formation process of the reflected shock when the shock front impinges on the nozzle has been clarified. using two different nozzles with the same contraction ratio. As the result, the effects of the shape of nozzle and the incident shock Mach number on the formation process, and the formation distance of the reflected shock were found. And it was elucidated that the reflected shock strength was dependent on not only the contraction ratio but also the shape of the nozzle.

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A transient flow induced by the shock front impinging on the four kinds of Laval nozzles, which were installed in the low pressure side of a shock tube, was observed optically by the schlieren method, and the starting process of nozzle and the value of initial diaphragm pressure ratio required to start the nozzle have been clarified. The nozzle starting time the duration of flow with constant Mach number were determined experimentally, as a function of the nozzle Mach number and the initial diaphragm pressure ratio. Moreover, it was found that the reflection of slip-stream caused by the Mach reflection of a shock wave is classified into two essentially different patterns of regular and irregular types. This phenomenon is similar to the two patterns of regular and Mach reflections occurring in the reflection of shock wave.

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We analyzed the turbulent pressure loss in the pipe flow of a dilute polymer solution by a method similar to that of Karman for Newtonian fluid or to that of Metzner et al. non-Newtonian fluid, and found that the friction factor in the pipe flow was expressed by two non-dimensional numbers: R_e and S(R_e=2ρRV/η_v, S=η_c/ρR², where η_v: viscosity, η_c: cross viscosity, ρ: density, R: pipe radius, V: mean velocity), and we showed that the analytical expression agreed with the experimental data well. In order to avoid the mechanical degradation, the concentrated polymer solution were injected into the water at the delivery side of the pump. Consequently, we obtained the same effect as the natural head flow. By way of an example, we tried an experiment on a hydraulic conveyor. Then the concentrated polymer solution was injected into a flyash slurry. Apparently, the Toms effect may be also recognized in the case of hydraulic conveyor.

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Until now, theoretical analyses using a digital computer have been inadequate. In this report, the following improvements were added to the conventional theoretical analyses: (1) Until the present, conventional analyses were carried out using for the most part an overflow type pump, a high pressure fuel pipe and a fuel nozzle. In this report, however, analysis was made using a by-pass control type pump (considered to be the basic structure of any pump system), a high pressure fuel pipe, a fuel nozzle, a fuel tank, a fuel feed pipe and fuel feed chamber. (2) In conventional analyses, when a void appeared in the fuel injection system, it was necessary to substitute a different equation and the boundary conditions of both ends of the high pressure fuel pipe were believed to be unsatisfactory. We have tried to improve on these points.

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It is necessary to decide the fuel compressibility, the specific weight, the sonic velocity, the flow coefficient and other physical characteristics when simulating a fuel injection system. Until the present, it would seem that the relationship between these physical characteristics and the primary factors of these characteristics has been unclear. For this reason, proper application of these characteristics could not be made. Therefore in this report, we measured the physical characteristics of the diesel gas oil and also of the fuel injection system used in this study. Moreover, after comparing the calculated values with the actual experimental values, a method of calculating the time interval for computation and the judgement values for permissible error, etc. were analyzed and were appropriately established. By using the methods described above, the results of the calculation matched adequately with the specific experimental factors, even when a void condition was present.

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This paper deals with a new mechanism, the generalized Oldham coupling. First the existence of the mechanism is deduced through the inversion of chain. This is a turning block double-slider mechanism with circular-arc-sliders and is a cyclical varying speed coupling. Next the relative angular motion between two shafts connected by the coupling is analysed and is verified experimentally. This coupling has one to one correspondence to the double crank mechanism on the condition that two mechanisms yield the same angular motion. In particular, the coupling corresponding to that having one crank of infinite length generates a new motion. The Oldham coupling corresponds to one of that having both cranks infinite length and is considered to be a special case of the generalized Oldham coupling.

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This paper purports to describe the construction and experimental results of a new surface tester with a stylus. The trial device consits of a sensor, a work table, a gear train, a servomotor, a binarycode drum, electric digital circuits, a code panel, and a recorder. Measured value of surface roughness is held on the code panel and after converted to voltage, it is given as a cuve recorded on a chart paper. The sensor touching periodically the surface of a test piece is an electric contact switch with a stylus driven by an on-off servomechanism. The sensor has a sensitivity of 0.1 micron of roughness height and a low measuring force of about 4 milligrams. It is also shown that this tester gives an accuracy of±0.2 micron.

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A basic discussion on an unsteady cutting process, in which the undeformed chip thickness increases or decreases linearly as in peripheral milling, is carried out. In order to make clear a change of the cutting mechanics with a varying underformed chip thickness, the deformation process of a process of a chip formed in previous cutting stage on the tool rake face must be took into consideration. In this paper, a time dependency of cutting energy is analyzed and theoretical equations are derived on the basis of changes in shearing energy in primary deformation zone and frictional energy consumed in tool-chip interface. Numerical solutions of the equations are calculated and compared with experimental results obtained in peripheral milling. A qualitatively good agreement of the variational configurations in both results shows appropriateness of the theoretical analysis. It is also confirmed that a theoretical discussion can interpret the characteristic variation of cutting mechanics in the milling process.

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In the present paper, the influence of the generation and growth of self-excited chatter vibration upon the surface finish is made clear under consideration of a particular work arrangement in centerless grinding. An application of the results gives some practical grinding conditions to make the growing up speed of vibration slow and one cycle of operation can be finished before the vibration begins to damage the surface finish.

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The drawing limits of mind steel and aluminum sheets were examined for the case of repeated drawing operations in which the blank was deformed incrementally as the rubber ring was repeatedly loaded and unloaded. The drawing condition used was base on the optimum one for the first drawing operation clarified in our 1st report. The obtained drawing ratio was 2 for mild steel, 3 for hard aluminum and 6 for half-hard and soft aluminums. When the work hardening of the blank was diminished by intermediated annealings, a maximum drawing ratio of 12 was achieved for soft aluminum. The strain distribution, shape and a surface roughness of drawn cups were also examined. Furthermore, the relation between the height of the drawn cup and the number of drawing operations was discussed for the case of using either a vulcanized natural rubber or a polyurethane ring and was compared with the data reported by N. A. Maslennikov.

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