The orthogonal cutting mechanism with the transitional deformation range (i. e. the "flow region" which exists between the rigid region of workpiece and the plastic region of steady chip), instead of the conventional shear plane, is analyzed theoretically in the case in which simple continuous chip is produced under the assumption of a perfectly plastic solid. Using the results, the experimental data for lead and brass are discussed. In all cases the starting boundary-line of flow region is situated under the conventional shear line, and the ending boundary-line above it. The inclination angles of both boundary-lines and the sector angle of flow region increase with rake angle. With an increase of depth of cut, the inclination angle of starting boundary-line increases, while that of ending boundary-line and, hence, the sector angle increase in the case of lead, but decrease in the case of brass. Furthermore, the strain of chip decreases with an increase of rake angle, and it has a tendency to decrease slightly in the case of lead and increase gradually in the case of brass with an increase of depth of cut.

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The need is becoming more and more urgent for bearings operating at very high temperatures. But present-day liquid lubricants are temperature-limited owing to their characteristics, but graphite is chemically more stable and capable of being used as a lubricant. So in pursuit of information concerning the performances of the angular contact type ball bearing operating in an electric furnace under the graphite-air mist lubrication at high temperature, the frictional moment and temperature of bearing have been measured. The conclusion reached on the experimental results is as follows. The bearing can be run at surrounding temperatures up to 800°C without appreciable damage. The smaller the particles of graphite, the less frictional moments are obtained, but at very high temperatures the grading and consumption of graphite have little influence on the frictional moment. Small change in frictional moment occurs in accordance with variation of surrounding temperature. The moisture content of graphite has little influence on the frictional moment. The cooling effect of air is somewhat remarkable.

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Formerly we had reported "the fluid lubrication theory of cylindrical roller bearing with consideration of relationship between viscocity and pressure" by approximate calculation. Afterward, applying the graphical solution in the report "film thickness between gear teeth" by Hersey, we have obtained the exact solution of load capacity of the cylindrical roller bearing under the fluid lubrication and report it in this paper. And in this report, two assumptive equations, namely parabolic and exponential equations, for the relationshirp between viscocity and pressure are compared. The load capacity of cylindrical roller bearing under the fluid-film lubrication changes with the change of the roller arrangement in operated bearing, and becomes infinite when the film thickness takes some value other than zero. So the possibility of the fluid-film lubrication in cylindrical roller bearing is large in the actual operation.

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This paper presents a theoretical investigation on the performance of cylindrical roller bearing under variable loads. In the first half, the analytical solutions of the frictional resistance, the fluid pressure distribution, the load-carrying capacity and the thickness of fluid film entrapped between two cylindrical surfaces under variable loads are given. In the latter half, it is described how the above solutions can be applied to the cylindrical roller bearing by using the equivalent coefficient approximately.

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It is known that a plastic deformation of a tube to be sunk beginns at the portion which does not come to contact with the die wall. This deformation of tubes is analysed under certain hypotheses. As a result, the deformation and the ratio of the stress to be added to cause the deformation to the yield stress of tube materials can be expressed in dimensionless terms determined by the sinking conditions and the properties of the materials. Experiments were made and confirm that the obtained equations are available for sinking dies designing.

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In this report the force acting normal to the die surface in rolling a thread by the flat die type machine was calculated according to YAMAMOTO'S theory on the thread rolling force, and the results of calculation were compared with REICHEL'S experiment. YAMAMOTO derived the general equation on the thread rolling force according to his own theory. The solutions of this equation for the case of the oil pressure type machine, in which the screw stock is revolved over 10 times until the thread is formed completely, coincide to his experimental results. But his equation must be modified somewhat in the case of the flat die type machine, in which the screw stock is revolved 5 to 6 times at most. After this modification, the equation was solved for the same example as REICHEL'S experiment. This solution was found out to be a good approximation to REICHEL'S experimental results.

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For testing plane curves given as a profile curves of templets and the like, the author divides these curves into many minute arcs, and measures the values of curvatures of each dividing points by use of a simple instrument with one or more indicators, and by integrating these values he calculates relative errors of these curves compared with the standard ones, or absolute values of coordinates of each points. In the present paper, he gives both theory and exprimental results of a method based on the above principle, and examines whether it is to be practically applicable.

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For the analysis of the running resistance, in advance, of snowcars, it is indispensable to make clear the value of y₀, viz. the depth of subsidence of caterpillar-plates on the surface of snowfall. In the present paper, the value of y₀ is investigated theoretically and experimentally, the influences of the hardness H of snow surfaces, the contact pressure between caterpillar-plates and snow surfaces w, the speed of vehicles V, and so on being ascertained.

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The writer carried out a theoretical analysis for the running resistance (on its unrelated part with speed) of caterpillar-snowcars on the basis of mechanical characteristics of snowfall and derived a general expression for the resistance by synthetizing the influence of running speed and the depth of subsidence of caterpillar-plates (in the 1st and 2nd Reports) to this analytical result. Further it was ascertained that the values of resistance calculated by the general expression nearly coincided with these values measured in the running tests, under the practical speed limit-around 20 km/h.

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