In the first report, the form of the grooved surfaces of the cylindrical cam with a swinging follower was analysed theoretically, and then various defects of the grooved surfaces for the actual cutting time and the idle movement time of automatic machines were improved. In this paper, the numerical calculation about the pressure angle between the cylindrical cam and the swinging follower was carried. Therefore it is expected that a guide to the design of cams used for automatic machines will be given very care fully regarding to the limit of the pressure angle.

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In the 2nd report the author studied the pressure angle on the grooved surface of the cylindrical cam with a swinging follower used for the threading attachment of Bechler Automatic Screw machine. It this paper, the theoritcal analysis for the specific sliding between the grooved surface and the swinging follower, for example, between the thread take-up cam and lever of the sewing machine was described, when various forms of the follower tip were given. In conclusion the relation between the swinging angle of the follower of various forms and the specific sliding was discussed, and the durability of this cam mechanism was also explained.

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Previously, the theoretical formulus on the form, the pressure angle and the specific sliding of the grooved surface of the cylindrical cam with a swinging follower, were derived. In tihis paper, the fine machining for the prevention of the surface roughness, the noise and the irregularities of the torque due to the interference between the grooved surface and the follower tip, was described. Morever, the author designed and trial manufactured a convenient machining apparatus which can finish the thread take-up cam very easily.

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In this papers, two relations concerning noncircular gears were introduced clearly and geometrically : first, the relation between the pitch curves and the base curves; second, that between the pitch curves and the tooth profiles. As a few concrete illustrations of these, the pictures of tooth profiles of noncircular gears with pitch curves formed with special plane curves were shown.

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In our last report^* under similar title the cutting pitch curve of a pseudo-elliptical gear was given by a two-termed expression in terms of polar tangential coordinates. In the present report the cutting pitch curve which is more closely approximate to an ellipse is given by a three-termed expression. The deviation of the pitch curve from the ellipse was calculated, and the result was compared with that of our last report. It cutting gears with the installation described in our last report, we had much trouble to renew the worm-wheel at everv chance of the dimensions of pseudo-elliptical gear. We eliminated the above mentioned inconvenience by using eccentric circular cams. Also we constructed for trial installation equipped with eccentric gears. The results are as follow : 1. Comparing the new pseuds-elliptical gears with those appeared in our last report, we have much closer approximation to and smaller deviation from the true elliptical ones, the theoretical value of deviation being less than 10% of that appeared. 2. Moreover in cutting gears of varipus dimensions the management of our new installation is far easier than that of our last one; i. e. we have only to adjust the eccentricities both the eccentric circular cams and the eccentric gears. * T. MATUYAMA and K. KON; "Cutting Pseudo-Elliptical Gears (Partl)" Transactions of the Society of Mechanical Engineers, Japan Vol. 20, No. 98, 1954 Part 4.

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Friction process on the cutting tool is discussed when the continuous chip is produced in dry cutting. It is shown that the chip on the cutting tool is in yield state and the shear stress on the cutting tool is equal to the shear stress on the shear plane. Considering this result and conditions of plastic deformation in the chip, new expressions for the shear angle and friction angle on the cutting tool are introduced. And then the thermal effect on friction process on the cutting tool is discussed for the case of the high-speed cutting.

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We found that the roughness of the grinder-finished surface and the grinding force were influenced by the oilness and the pentrating of the coolant from the grinding base researches, and we could relate the surface tension and the oilness of the coolants to the roughness of grinder-finished surface and the grinding force. And it was found that the thickness of the grinding surface layers were changed from 22μ to 42μ, by the action of the oilness of the grinding coolante.

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In order to investigate the performance characteristics of the internally cooled grinding wheel more minutely, "Coolant through the wheel" practice has been applied to the offhand grinding of thick plate. The experiments show that the longer the length of contact arc between wheel and work, the more effective the "Coolant through the wheel" practice, the very few amount of coolant may be. perfectly utilized in this practice, and it does not take effect on the grinding performance to cool the body of work only.

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In the first report it was shown that the analysis of sheet metal bending might be based on the tensile stress-strain diagram only, although the deformation was very complicated. From this point of view, the second report dealt theoretically with the plastic bending of sheet metal by V-type punch and die. The analysis consists of two cases. First, sheet metal is supported on the edges of V-type die and loaded at the center line. Secondly the supports are transferred from the edge to the face of V-type die and load acts at the center as before. The results obtained in the analysis agree very well with the experiments. This paper contains the results of the experiments in the progressive cases up to so-called coining and the analysis of profile after bending. As a result, it has been confirmed that the angular spring back Δθ approaches asymtotically to a definite value, if the load increases beyond a certain magnitude.

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For example, a method of prevention of wear of the Rail and the Tyre, the test of defacement was studied the effect of heat-treatment of the rail and tyre, under the dry condition by Amsler-type Abrasion Testing Machine. As a result, if we heated one, the other untreated was suffering from concentrated pressure, therefore we should take care of practical use and in case of both heat treated, we find out good effect.

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By means of the strobo-flash type high-speed photography the motion of running shuttle, the state of filling re-winding and the motion of picking mechanism of power loom were photographed at a speed of 17Or. p. m. From these photographs, the abnormal running form of the shuttle, the spiral shape of ballooning of re-winding weft and the motion of swell cao be seen.

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In pressure control systems, for example as shown in Fig. 1, we sometimes experience that when the initial disturbance in pressure is smaller than a certain limit the system is stable and the pressure fluctuation diminishes, but when the initial disturbance is larger than the critical limit the system is unstable and the pressure fluctuation grows. The author treated this phenomenon as caused by the non-linear resistance of flow in the pipe connecting the measuring element (diaphragm) and controlled medium (air in tank). And he found that the critcal value of pressure disturbance mentioned above was given as [numerical formual] supposing the resistance being proportional to the square of velocity of flow in the pipe, where α, b are constants in expression (2) showing the characteristics of controlled medium, K is the coefficent of resistance of flow as in expression (1) and κ is also a constant in expression (3) showing the characteristics of servomotor.

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Mechanical polishing is recently being required for the reason of the appearance and wide-spread use of sintered alloy contacts. As the mechanical polisher, we designed a machine based on lapping, and made experiments on the sintered Ag-W alloy contacts. Furthermore, we tried to find a solution which might, in future, help to make clear the mechanism of plane contact of metal pieces. Then, substituting the measured values of their contact resistance, roughness and load into a theoretical equation based on an assumed contact condition, we calculated both the effective contact points and the true contact area. Upon studying the relations that exist among the above mentioned figures, we found that, the increase of effective contact points which is due to the high degree of surface finish, had especially a great deal of effects on both the decrease of the contact resistance and the other performances of contacts.

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