Theoritical formulas for desingning an exponentional or conical horn for longitudinal or torsional vibration in ultrasonic cutting are established in this report. Then, the mechanism of the tool post that is much important for developing the fundamental research or effective application to various cutting tools is investigated. And it has been found that the structure of an ultrasonically vibrated cutting tool calculated by these formulas has a style suitable to coventional machine tools and has several nodes. An ultrasonically vibrated cutting tool can be fixed statically on the machine tool by supporting these nodal points.

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The cutting mechanism in ultrasonic cutting is considered in this report and the main results are as follows : 1) Amplitude and frequency have relations with the cutting speed and the critical cutting speed V_c=0.376 af m/min (a : amplitude micron, f : frequency kirocycle). 2) Cutting time t_c in one cycle is very short. (for example t_c=10^-6s3) Cutting length l_T in one cycle is V/f. (for example l_T=0.08 micron) 4) And at a cutting speed lower than this critical cutting speed, the cutting tool is separated from the chip in each cycle and is cooled by air or can be lubricated exactly by using the usual lubricant without special cutting fuild.

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The motive of this study is developed with an analysis of the mechanism of ultrasonic cutting and experimental results by using the single cutting tool that vibrates to the traverse direction. Af first, in this report, this ultrasonic cutting is considered. In this ultrasonic cutting, the cutting resistance is decreased and the cutting ratio is increased compared the conventional cutting. But, owing to the ultrasonic friction between the tool-edge and the work peice, high temperature is occured at the tool-edge and, in early cutting time, wear of the tool is induced. It will be performed smoothly by using a grinding wheel instead of this single cutting tool and obtained the efficient effects.

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The outline of the effects in ultrasonic grinding by using the longitudinally ultrasonically vibrated grinding wheel was investigated (frequency : 20kc amplitude : max. 22μ, work peice : aluminum, copper, brass, high speed steel). The results are as follows : 1) It is found that the grinding wheel can be vibrated and revolved without any trouble by this described method. 2) This longitudinal ultrasonic grinding is more effective machining at lower speed. 3) The grinding resistance is decreased by increasing of amplitude or decreasing of grinding speed. 4) Owing to this ultrasonically vibrated wheel, powdery chips are scattered and residual chips are not observed on the surface of grinding wheel in spite of this low grinding speed. 5) The bur is not occurred at the machined surface edge for any soft materials.

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In this paper, the opportunity of ths study is described and the punching mechanism is considered and the outline of this effective ultrasonic punching is investigated. By using the conventional press, the crack is occurred in cold punching and so is generally heated, but in this ultrasonic cold punching, the crack is never observed and moreover, the punching resistance is decreased to 1/2∼1/8 that of conventional punching.

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When the cutting temperatures of a drill point are not uniform along both cutting edges, it is impossible for us to measure the temperature distribution by the conventional drill-work thermocouple method. In order to study these problems, we prepared the special drill-constantan thermocouple, welding a constantan wire of 0.1 mmφ on the flank of the drill directly near the cutting edge. We thus made clear both the distribution of temperature along the cutting edge and the unequality of the temperature between the two lips of the same drill.

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It was impossible to study the lateral spread during the rolling analytically, because in the conventional studies for rolling it used to be treated as a two-dimentional problem. The author adopted the mean slipping angle between the rolls and plate and developed the three-dimentional consideration of rolling stresses in the first report. Using these results the author has obtained a new formula of spread during the hot rolling as follow : [numerical formula] then [numerical formula] and [numerical formula] The validity of new formula is also discussed in this report, using the plasticine which has same plastic behavior of steel in hot states.

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Conventional calculation of rolling load has been treated on the basis on the assumption of two-dimentional deformation, but such an assumption cannot be used for the hot rolling practice in which the ratio of width to the thickness of material is smaller than 20, when the lateral spread occurs. The author developed the three-dimensional consideration of rolling stresses and spread during the rolling in previous report. Using these results, the author obtained a new formula of rolling load in hot states as follows : [numerical formula] In this report the calculated results were presented for various rolling conditions.

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However very important the performance of lubricant for the drawing of medium or high carbon steel wire is not only for the efficiency of the work, but also for the quality of the drawn wire, only few of systematic approaches to wire drawing lubrication problems have been reported. The author investigated performances of many lubricants under elevated die temperatures, and confirmed that they dominate the efficiency of lubricants under practical drawing conditions. From this point of view, he investigated many lubricants especially the mixture of lime and soap, and made clear the coating effect of solid lubricants. He also examined and improved metallic soaps and phosphate coatings. On the other hand, he investigated the effect of die cooling.

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Analytical solutions of the pressure distribution of externally pressurized concentric journal or parallel surface thust bearings are obtained for compressible and incompressible fluids, for several bearing configurations, by means of complex potential functions. Flow rates, and approximate evaluations of the effects of eccentricity and sliding speed, are also obtained. A bearing design factor for restrictor compensated bearings is presented, and optimum values for maximum bearing stiffness are determined. Comparisons are made between theoretical calculations and available experimental data.

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There are several hypotheses on the mechanism of rolling friction, but they are not recognized as an established theory. Authors recently reported the experimental research on the high speed rolling friction and clarified the many characteristics which cannot be expounded by the former hypotheses. In this paper, the new hypothesis about the rolling frictions at every case of the start, low speed and high speed are presented. The rolling friction at start is attributed to the potential energy loss caused by the surface roughness and theorized considering the elastic deformation. The potential energy loss theory cannot be applied to the kinetic rolling friction, but the low speed rolling friction is due to the sliding friction caused by the meshing of contact surfaces and then the high speed rolling friction is resulted from the energy loss with the minute collisions occur on the dry surface and from the fluid friction on the lubricated surface.

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Dynamic loads on spur gear teeth are examined by a gear testing machine and a strain gauge apparatus. The ground pinion and gear are tested at the periphery speed 80 m/s and below. Some teeth of the gear have normal pitch errors which were given about 15μ on purpose. The magnitude of the dynamic load increases at the critical speed at which the conjugating frequency is equal to the natural frequency of the vibratory system consisting of the pinion, gear and the teeth stiffness. At a speed higher than the critical speed, the heavy dynamic load occurs on the tooth which has the postitive error. If there is a tooth which has the negative error, the tooth tends to carry no load, and the heavy dynamic load will occur after several teeth. The calculated results, which are analysed as a vibration problem, are nearly coincident with the measured results.

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The nominal coefficient of friction between the wire rope and sheave lining was measured by an experimental device for koepe winding. The angle of contact is 188 degrees in the device and nearly equal to that in actual winders. On that occasion, the kind of lining and paint, surface pressure and slip velocity were changed variously. Examining the relation between the nominal coefficient of friction and the rope pull, we concluded that this measured value is applicable to the designing calculation of actual winders.

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