Der Bericht enthalt im ersten Teil allgemeine Vorstellung des Entwurfs fur ein internationales Passsystem, das an die zweite Konferenz der ISA-Komitee fur Passungen, Mai 1931,vorgeschlagen wurde. Im zweiten Teil wird der Vergleich zwischen dem japanischen Passsystem und dem ISA-Vorschlag durchgefuhrt. Auf Grund des Vergleichs wird der folgende Schluss bekommen : Die kunftige Fortschritte in der Herstellungstechnik der Lehren in Japan lassen es nicht unmoglich erscheinen, dass zu einem spateren Zeitpunkte das vorgeschlagene Passsystem praktisch einwandfrei vorgenommen wird.(Original p.895)

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In a 3 1/2 H.P. farm engine of the Otto cycle, using a throttle valve governor, the exhaust cam was changed in form in order to close the exhaust valve before certain degrees of the first dead point, while the inlet valve had no change as it had worked automatically. The result was remarkable in the efficiency at light load. The gain was 11% at 2 H.P. and 19% at 1 H.P., as compared with the original cam.(Original p.900)

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[figure] [figure] In Fig.1 showing the elevation of the economiser, flue gas comes from the left hand side at temperature t_<g_1> and surrounding the 1st tube uniformly, gives the heat quantity Q_1 to feed water, and then gas temperatu refalling to finally t_<g_2> and surrounding the 2nd tube uniformly, it gives Q_2 to feed water and soon. Thus the gas surrounds the nth tube at temperature t_<g_n> and gives Q_n to the feed and leaves the economiser at temperature t_<g_<n+1>>.[table] then the heat content of gas at [numerical formula] In the equation (1), if t_<g_1>, G_<g_1>C_g as well as Q_1,Q_2,…Q_n are known, we can find t_<g_2>, t_<g_3>, …t_<g_n>, t_<g_<n+1>>. Next, we require to find the value of Q_m, the heat quantity transfered to the mth tube. From equations of heat trasmission of tube, we get [numerical formula] where t_<g_m> : gas temperature at the mth tube, t_<w_m> : temperature of water at the exit of the mth tube, t_w : temperature of water at the inlet of the mth tube, K_p : 1/{1/α_iD_i+(log_e D_0/D_i)/2λ+1/α_0D_0}, coefficient of heat transmission of tube, α_i : film coefficient between wall and feed water, α_0 : film coefficient between wall and gas, λ : conductivity of wall, D_i : inner diameter of tube, D_0 : outer diameter of tube, L : length of a tube, C_m : specific heat of water, On the other hand, heat quantity transfered to the mth tube. [numerical formula] Therefore, if K_pLt_<g_1>G_wC_wG_g are known, we can find t_<g_2> t_<g_3>…t_<g_n>t_<g_<n+1>> and Q_1 Q_2…Q_n by (1) and (2). Consequently, the total heat transfered to all tubes n×n' is [numerical formula] and the temperature of water at the outlet of each tube is [numerical formula] and the temperature of water at the exit of the economiser is [numerical formula] In practice, two cases such as (a) t_<g_1>t_wt_w' are given, and heating surface and t_<g_<n+1>> are unknown. (b) t_<g_1>t_wt_<g_<n+1>> are given, and heating surface and t_w are unknown. will often occur. In such cases, [numerical formula] the left hand term is constant and Q_1Q_2…in the right hand term can be found, if definite tubes are used and G_w, G_g etc can be assumed, so that we can investigate the number of tubes n in raw. September 1932] Putting the total quantity of feed water, X. [numerical formula] then we can find n', the number of tubes in column. [numerical formula] In this case, the left hand term is also constant, so that we can find n and n' as in the case (a).(Original p.903)

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Experiment No.1. A fly wheel was fitted to the cone pulley of a 16" Pillar Shaping Machine to see what effect this would have on the motion of ram. No effect was descovered by the author. Experiment No.2. A ram made of No.12 aluminium alloy was then fitted to the machine to see what saving of driving power could be effected. This new ram saved much power on the return stroke and, even under a moderately heavy cut, produced a plane as good as that produced by a cast iron ram. Experiment No, 3. The author made a close inspection of the plane produced and found that the surface was concave instead of being straight. Two steel guide bars were then added to help the ram motion and this idea was found to be very effective, a better plane being produced.(Original p.908)

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Tool dynamometers which are generally used for measuring the cutting force, are classified in two groups, namely the hydraulic and piezoelectric dynamometer. The former is very simple in its construction, but it allows the point of tool a displacement relative to the tool rest ; for example, in the case of a lathe tool dynamometer the point of tool is depressed in a great deal in the working, condition, and consequently the corresponding change of tool angles is caused. The latter or piezoelectric dynamometer needs not only delicate manipulation, but a great precaution for the leakage of electric charge is necessary, especially when the air is damp. In a new dynamometer devised by the authors, the recording of the cutting force is carried out by a pure mechanical method ; a rectangular bar is twisted by the force, and its angular displacement is magnified by means of levers and is recorded. As its construction is very simple it is useful not only in laboratories, but also in workshops. So far as the depression of the tool point is concerned, it is superior to a certain hydraulic dynamometer made in Germany. The said depression in the authors' dynamometer, for example, when the deflection of the recording pen is 20 mm, is 39% of that in the hydraulic dynamometer at the corresponding deflection of the pen, and 21% when the oth r fulculum is used. The capacity of the dynamometer may be easily altered by altering the torsion bar or the ratio of magnification. It is proved by calibration that displacements of the recording pen are in almost perfect rectilinear relation with the loads, and that there is neither hysterisis nor time effect. In the present paper, the results of measurements are also reported. The experiments were carried out for mild steel, cast iron, gun metal, copper, alminium, bakelite and ebonite at various combinations of feeds and cutting depths, which make the cutting area 1'26,0'945,0'623 or 0'315 mm^2.(Original p.914)

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In this paper, an attempt is made to solve the problem of a rectangular plate which is simply supported or perfectly or imperfectly clamped at the periphery and supported by many elastic beams parallel to the edges of plate and subjected to a distributed load in any manner. To simplify the problem, it may be assumed that the elastic beams lie symmetrically to the center line of the plate and the latter is subjected to an uniformly distributed load. The reaction, produced by the elastic beams can be considered as the external force acting on the plate, so the differential equation of an elastic plane can be written as follows : - [numerical formula] September, 1932] p_0=uniform load, a, b=breath and length of the plate respectively, x, y=rectangular co-ordinates, the origin being taken at the corner and their directions coincide with sides of the plate, E_<a/2>, E_<a_i>, E_<b/2>, E_<b_i>=moduli of elasticity of the elastic beams at x=a/2,x=a_i, y=b/2 and y=b_i respectively, I_<a/2>, I_<a_i>, I_<b/2>, I_b_i=moments of inertia of the elastic beams at x=a/2,x=a_i, y=b/2 and y=b_i respectively, Now the auther assumed that the deflection of the plate can be represented by the following formula, [numerical formula] In this equation, λ is equal to a/b and for α, β we put the next limitations, i.e.0&le;α&le;1,0&le;β&le;1. Therefore, for α=β=0 or α=β=1,the equation (2) satisfies the boundary condition of the freely supported or perfectly clamped rectangular plate respectively. But, the equation (2) is not necessarily the solution of eq. (1), hence we can determine the unknown coefficient A_<mm> in eq. (2) as to satisfy this condition. The auther has introduced the general conditional equation for A_<mm>, and for examples, some numerical calculations and experiments on special cases have been carried out. From these sesults, he has confirmed that the theoretieal results well coincide with those of the experiments.(Original p.924)

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Es behandelt sich um die Spannungen in irgend einem Punkt in Walze zuerst und nachher die maximale Schubspannung : Die Spannungen σ_y, σ_z und τ_<y_z> lassen sich leicht unter der Benutzung von Sparinungsfunktion berechnen und damit wird die in folgender Beziehung stehende maximale Schubspannung τ_<max> berechnet, [numerical formula] Die Punkte mit konstantem Wert K≡τ_<max>/〓 sind errechnet und mit Kurven zeichnerisch dargestellt. Die Schar von auf dieser Weise erhaltenen K-Kurven stimmt ziemlich gut mit der der schon experimental erhaltenen Isochromen-Kurven in Photoelastizitat uberein.(Original p.931)

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If we define the acid by the concentration of H^+, a strong acid has a large concentration of H^+, whilst weak one is of a small concentration. In the above defined weak acid Fe^<++> acts as the positive catalyser. We can use this nature of Fe^<++> for the etching of strain figures of mild steel. Using CuCl_2 and H_2O_2 as the oxidizing agents, C_3H_5(OH)_3 as the retarder and HCl as the provider of H^+, the author obtained very good results. For an example, a titration curve of the above case, by measuring the electrical potentials of the liquid between Pt and Cu plates at 13℃, is shown in Fig.1.[figure] Further, the author, studied on the process of the failure of mild steel and for the engineering purpose classifies the strain due to stress as follows : - 1. Strain due to individual crystal. 2. Strain due to body or configurated crystals. a. Elastic strain. B. Plastic strain. C. Local strain. In this paper, their natures are discussed from the stress-strain diagrams and the strain figures. The strain due to individual crystal is difficult to measure by ordinary commercial testing machines, but the strains due to body which are elastic, plastic and local strains, can easily be shown by a stress-strain diagram. In case of compression test, using an Amslers'20 ton testing machine fitted with an enlarging apparatus, the author obtained the following diagrams. The elastic strain developes in a range of a in Fig.2. and shears the material in the direction of nearly maximum shearing stress and shows the most remarkable deform along the axis of loading. The plastic strain occurs after the material is strained by the elastic strain and shears partly the material without definite direction, because it develops in the elastic parts of the material which are not sheared by the elastic strain. Difference between them is clearly shown by the another's compression tests, using laterally holed test pieces of two kinds as the author's compression shown in Fig.3.[figure] [figure] In the Fig.3,the left hand side diagram corresponds to the left hand side test piece and the right hand one to the right hand side test piece. In the former case, the test piece fails at first around the hole and then at upper end. In the latter case, the plastic strain, developed around the two holes, occupies the whole space of surface, to that the elastic strain or sudden change can not occur. Lastly, the author proposes two methods in consideration of the mechanical properties of materials which are called the stress-straining time diagram and the stress-energy diagram. Results of futher study will be reported in near future.(Original p.934)

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The Department of Communications has adopted the conveyor system in handling of parcels and letters in the recently completed building of the Tokyo Central Post Office, in order to meet the incessantly increasing mass of mailmatters and at the same time to avoid unnecessary labour for the personnels. The process of handling mailmatters in Japan is different in certain respects from those in other countries, where mechanical handling is already adopted, so that the author had to establish novelties in carrying out the handling system. The principles followed in the design are : 1) the adoptation of machinery, which may lead to a minimum maintanance cost with simplicity in the operation. 2) high value is set on the safe operation, without any danger of clogging or retarding of progress and damage or loss of the mailmatters. 3) maintenance of the present methods of handling as far as possible. 4) preference on the home products, except unavoidable cases. The essential of the handling system lies in the interconnection and timing of the machinery to the manual handling. As to the construction of machinery itself, not much trouble is encountered and there is no special point, except that electrie are welding is widely utilized, most of the heavy cast iron parts being dismissed from the office rooms, Also much consideration is taken in the prevention of vibrations and noises. The floor area of the working rooms amounts to 18000 sq.m. and the length of conveyor lines is about 1560 m. There are installed many other mechanical appliances, such as elevators, lifts and subveyors, electropost, dust collectors, and plain and spiral chutes, and the total power required is about 250 HP.(Original p.940)

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