精密機械
Print ISSN : 0374-3543
47 巻, 8 号
選択された号の論文の19件中1~19を表示しています
  • 吉川 弘之
    1981 年 47 巻 8 号 p. 907-912
    発行日: 1981/08/05
    公開日: 2009/06/30
    ジャーナル フリー
  • 岩田 一明, 森脇 俊道, 村田 伸宏, 八木 徹也
    1981 年 47 巻 8 号 p. 913-919
    発行日: 1981/08/05
    公開日: 2009/06/30
    ジャーナル フリー
    In order to improve environmental conditions of metal cutting operations, a new hygienic cutting fluid of neat oil type was developed, and its performance tests were carried out for turning operations from various viewpoints. The newly developed cutting fluid consists basically of liquid paraffin derived from saturated hydrocarbons, and contains edible hydrogenated rapeseed oil and refined palm oil as lubricant. The total amount of aditives is 40%. The properties of the new cutting fluids are equivalent to those of JIS 2-3 when compared to those which contain extreme pressure additives. Some typical toxic tests were carried out, and it was approved that the toxicity of the new cutting fluid was extremely low when compared with other commercially available oils. The newly developed, cutting fluid also showed a good long term stability. Machinability tests of plain carbon steel containing 0.45% C (JIS S 45 C) were carried out with high speed steel tool (JIS SKH 9) on an engine lathe. The newly developed cutting fluid showed similar or even better performances at cutting speeds from 70 to 80m/min in tool life, surface roughness and chip disposal etc. when compared with a commercially available cutting fluid of JIS 2-3 type.
  • AE法による破壊過程の解析
    本間 恭二
    1981 年 47 巻 8 号 p. 920-925
    発行日: 1981/08/05
    公開日: 2009/06/30
    ジャーナル フリー
    Previous work dealt with the effects of pores on macroscopic fracture of the vitrified grinding wheels. In the present work, fracture mechanisms of the same materials from the stages of microcrack growth to final fracture under uniaxial tensile loading are discussed by means of the acoustic emission monitoring which provides the information of dynamic morphological changes of them. Results of the emission monitoring revealed that a clear correlation between the crack growth behavior and the emission amplitude distributions was founded, and the incremental microcrack growth in the location of inhomogeniety could be detected throughout loading. It was also found with the specimens having sharp notches that, prior to the final fracture, intermittent fracture (break in two pieces) of abrasive grains or bondbridges or both took place, while with the specimens without notches that a simultaneous coalescence of each microcracks extended sufficiently to critical length should cause the final fracture. Although only qualitative discussion of the results were attempted in this study, the type of information obtained can readily be used for qualitative interpretation of the fracture mechanics of the materials.
  • 岡田 勝蔵, 高橋 昇
    1981 年 47 巻 8 号 p. 926-931
    発行日: 1981/08/05
    公開日: 2010/02/16
    ジャーナル フリー
    Precipitate particles are occasionally adopted to study the deformed superficial layers. The aim of the present paper is to examine experimentally the structure, size and distribution of these particles formed at the deformed region by high voltage transmission electron microscopy. Specimens of Al-4% Cu alloy, solution treated at 540°C for 30 h and water quenched, are scratched with a diamond cone and aged at 260°C for 2 h. The main results obtained are as follows. (1) Isometric θ-phase precipitate particles at the heavily deformed superficial region are observed. (2) The size of plate-like θ'-phase precipitate particles at the plastically deformed region are smaller than that at the undeformed region, on the other hand, their density is larger than at the undeformed region. (3) Preferential precipitation on a particular habit plane of θ' depends on the crystal orientation of the scratching direction.
  • 切削あるいは塑性変形によってみぞを生成する砥粒切れ刃の連続間隔
    中島 利勝, 中川 平三郎
    1981 年 47 巻 8 号 p. 932-937
    発行日: 1981/08/05
    公開日: 2009/06/30
    ジャーナル フリー
    The successive spacing and its distribution of cutting or ploughing edges are experimentally made clear by analyzing interference grooves on ground surface and correlating grooves with positions of cutting edges on the wheel surface. Then discussed are the effects of grinding conditions, such as plunge speed, speed ratio, grain size and dressing condition upon the successive cutting edge spacing. The successive cutting edge spacing distributes widely, following the Gamma Distribution. The successive spacing of cutting edges concerning cutting or ploughing has a close relation to the real interference depth of wheel. The successive cutting edge spacing is not a characteristic value of the wheel, but is affected by grinding conditions.
  • ステンレス鋼, 軸受鋼研削の場合
    松尾 哲夫, 園田 真治
    1981 年 47 巻 8 号 p. 938-943
    発行日: 1981/08/05
    公開日: 2009/06/30
    ジャーナル フリー
    Conditioning of steel is an indispensable process to obtain high quality steel products. Snagging has recently attracted much attention as the more advantageous conditioning method from stand-points of energy-saving and air pollution compared to other methods, such as oxygen scarfing or mechanical chipping. An important problem in snagging is the selection of proper wheel type, but correct selec-tion is hampered by the lack of exact information. In our previous work, a laboratory snagging test under constant load was made on an S 55 C steel, using different wheel types. In the present study, the same snagging test was carried out on SUS 304, SUS 430 and SUJ 2 steels using seven different wheel types. This experimental work allowed the metal removal rate, the wheel wear rate and G-ratio to be determined. It was found that the 32 A wheel was the best from a stand-point of removal rate, while from stand-points of wheel wear or G-ratio the ZS and ZN wheel types were superior to the alumina wheel types. In special, the ZN wheel showed the higher G-ratio over the ZS wheel for the grinding of SUS 304 steel. Also, it is noted that the geometry of the surface generated depends largely on wheel type, and then, a great difference in the geometry is seen even between the ZS and ZN wheel types.
  • 高梨 三郎, 庄司 彰
    1981 年 47 巻 8 号 p. 944-948
    発行日: 1981/08/05
    公開日: 2009/06/30
    ジャーナル フリー
    This paper describes some experiments on the coefficient of kinetic friction between two cylindical surfaces considered to be approximately equal to the contact of gear teeth surfaces. The experiments were made for finding out the coefficient of kinetic friction between the contact surfaces of plastic gear teeth. The followings are found from the experiments. The coefficient of kinetic friction was influenced by the lubricating conditions and sliding velocity, and slightly depended on the load. It was hardly influenced by the dimensions of both cylinders so far as present experiments are concerned. As the summary of these experiments, the coefficient of kinetic friction jet concerning the present experiments can be expressed as the following :
    μ=C0Pn-0.1·V0.23
    where, C0; coefficient to be determined by the combination of materials and lubricating conditions, Pn; load (N), V; sliding velocity (cm/s).
  • 高浜 逸郎, 藤田 昌大, 永田 茂, 高橋 一博
    1981 年 47 巻 8 号 p. 949-955
    発行日: 1981/08/05
    公開日: 2009/06/30
    ジャーナル フリー
    The purpose of this paper is to investigate the locomotion during the normal walking after analyzing the experimental data. Here the data of moments at joints are obtained with sufficient accuracies by the method of analyzing the data which has been proposed in previous report and the patterns of their changes are discussed with relation to the gait patterns. These discussions derives essential points in locomotion during normal walking. Further the data of moment obtained here are compared with a few data obtained by other walkers. It is confirmed by this comparison that the data obtained here gives a typical feature among all quoted data and their values almost hold averages of all data throughout a cycle of walking.
  • 1981 年 47 巻 8 号 p. 955
    発行日: 1981年
    公開日: 2010/11/19
    ジャーナル フリー
  • 静電容量法による摩耗進行追跡
    武士俣 貞助, 岩井 実
    1981 年 47 巻 8 号 p. 956-961
    発行日: 1981/08/05
    公開日: 2009/06/30
    ジャーナル フリー
    This report concerns the relationship between the extent of intermesh and the degree of toothsurface wear when a polyacetal spur gear is engaged with a steel gear. In the present study, a change in backlash was observed by measuring the electrostatic capacity across the sectorial electrodes mounted on the side of the tested gear. By measuring the distribution of temperature from the circumference to the center of the gear caused by frictional heat on the tooth surface, a study was made on the wear on the tooth surface with respect to the effect of thermal expansion on backlash. Results obtained are as follows : (1) Observing changes in backlash during operation, it was found that when the amount of thermal expansion is greater than the amount of wear, backlash is reduced below that immediately after the starting operation. (2) A greater load on the tooth increased the amount of wear per one revolution resulting in rapid increase in backlash. (3) It was found that the wear rate was largely influenced by the applied load and less influenced by the number of revolutions.
  • 断続切削時における食いつきの研究 (第3報)
    中村 示, 山本 明, 河村 一郎, 今井 誠
    1981 年 47 巻 8 号 p. 962-968
    発行日: 1981/08/05
    公開日: 2009/06/30
    ジャーナル フリー
    A primary factor of the wide fluctuation of tool life owing to an engagement angle Ea in face milling may expect that the transient stresses in the cutter tooth are varied with the angle Ea, and then, their transient stresses distribution upon the rake surface for the various angle Ea at milling are analyzed by photoelastic experimental method, in which the lead alloy plates are cut with a tool of epoxy resin. Moreover, it makes a model of stresses distribution from these results and this model is applied here for the computational stress analysis in the tool on the same cutting process by the finite element method and these computed values are verified with the photoelastic experimental results, after that, it makes another attempt to calculate about the varied tool wedge forms and boundary conditions. The main results have proved as follows. When a rake surface of tool contacts at the outward face of workpiece with a positive engagement angle and it bigins biting from apart point of the tool edge, the parallel stress σy for the rake surface acts only at a neiborhood of tool edge as tensile stress, at last, their stresses turn to compression one in entirely biting to the tool edge. Thereupon, these tensile stresses are induced by the friction force of chip flowed on the rake surface. Such the alternating stresses acted at the neiborhood of tool edge become a cause of chipping or breakage and it is supposed that stresses exert a great influence upon the tool life.
  • 田口 三生, 横山 一男
    1981 年 47 巻 8 号 p. 969-974
    発行日: 1981/08/05
    公開日: 2009/06/30
    ジャーナル フリー
    In order to find the method by which the chips are effectively broken, it is necessary to observe in detail the chip breaking phenomena. In this report, the chip breaking phenomena are photographed by the high speed camera, and the relations between the chip breaking types and the cutting conditions are investigated by them. The following results are made clear. (1) The chip breaking types are able to be classified into three types : the type in which the chip hits the workpiece, the type in which the chip hits the tool flank, and the type in which the chip is broken at the point of tool tip. (2) As the cutting speed increases gradually, the chip breaking type generally transfers from the type in which the chip is broken at the point of tool tip to the type in which the chip hits the workpiece and finally to the type in which the chip hits the tool flank, or it transfers from the type in which the chip hits the workpiece to the type in which the chip hits the tool flank. (3) The chip breaking types change according to the kinds of workpieces. (4) The chip breakability is decided by the frequency in occurrence of the above three types.
  • 細井 俊明, 細井 良祐, 浅野 幸三, 堀内 宰, 長谷川 嘉雄
    1981 年 47 巻 8 号 p. 975-980
    発行日: 1981/08/05
    公開日: 2009/06/30
    ジャーナル フリー
    A new type of carbide-tipped twist drill has been successfully developed in order to drill steel workpieces at considerably higher feed speed than that of the conventional HSS twist drills. Design principle, cutting mechanism and capability of this new carbide drill are discussed with reference to a conventional HSS drill. The new carbide drill is characterized by special shapes of the cutting edge, the chip pocket and the flute. It has been ascertained experimentally that the special edge shape makes the tool free from edge chipping which occurs otherwise in steel cutting. Also the chip pocket and the flute design guarantee both periodic fracture and smooth transport of the chip along the flute. Drilling forces for the carbide drill have been experimentally known to be greater than that of conventional HSS twist drills. The carbide drill gives fairly closer hole accuracy than the HSS drill.
  • 下穴偏差の切削状態に及ぼす影響
    佐久間 敬三, 清田 宏
    1981 年 47 巻 8 号 p. 981-986
    発行日: 1981/08/05
    公開日: 2009/06/30
    ジャーナル フリー
    Cutting action, effected by the alignment error between pre-bored hole in workpiece and spindle axis under rotation, is examined in reaming steel by means of a dynamometer, which is specially designed to measure torque, thrust and radial forces in two directions (X, Y). From these results, relationships between variable components of cutting forces and sectional profile of machined hole are discussed. In rotation of tool axis, eliptical movement is mostly observed. It causes the difference of two variable components of radial force (ΔRX, ΔRY), which are related to the variable torque. Variable force components during one spindle rotation have an influence on the eliptical profile in the machined hole section, and variable components, whose frequencies correlate to number of tool teeth, influences the number of lobe in multi-cornered profile. Eliptical movements of tool axis affect on the state of metal-flow in sub-surface of hole wall, and cause the roundness error. Since the alignment error is unavoidable in hole-making operations, the ideal cutting motion cannot be performed in reaming process.
  • 切削模型とエネルギー解法および二, 三の予備的結果
    広田 明彦, 笠原 和夫
    1981 年 47 巻 8 号 p. 987-993
    発行日: 1981/08/05
    公開日: 2009/06/30
    ジャーナル フリー
    The tool angles such as the normal rake angle and the inclination angle vary continuously along the cutting edges of a twist drill, furthermore the cutting velocities also change in magnitude and direction at any point on the cutting edges. There-fore the chips are produced with various chip flow and normal shear angles, and the cutting process is three dimensional. In this paper it is assumed that the chips at infinitesimal parts on the cutting edges are described by simple shear plane oblique cutting models, and the whole chip formation process is treated as an accumulation of the infinitesimal parts along the cutting edges. A cutting model, in which the condition of side curl of the chip is considered, is developed and the energy method is extended to the case of drilling process. Then they are used with the appropriate data obtained in orthogonal cutting to predict the chip formation along the cutting edges and cutting forces in the case of drilling with pilot holes. Preliminary examination shows that the proposed cutting model and the energy method give good qualitative explanations on the chip formation and the torque.
  • 川崎 晴久
    1981 年 47 巻 8 号 p. 994-999
    発行日: 1981/08/05
    公開日: 2009/06/30
    ジャーナル フリー
    リニアサーボモータ駆動によるキャリジ送り機構の高性能化を図るために, 振動特性について検討を行い以下の結論を得た.
    (1) 案内・支持機構の剛性に起因する縦揺れについて解析し, その固有振動数の向上を図る条件を明らかにした.
    (2) リニアセンサ取付位置による系の動特性について解析し, 次の点を明らかにした.
    (a) 垂直軸に関して, センサ取付位置と推力作用点とがキャリジの重心をはさむ構成にすると, 系は不安定となる.
    (b) 位置整定時間を最小とする最適センサ取付位置が存在する.一般に, 制御目標位置が重心より離れるにつれて, 最適センサ取付位置も重心より離れた位置となる.
    (3) モータ最大電流に制限のある場合の位置整定時間を明らかにした.
    ここで実験に用いたリニアサーボモータは, 既に試作プリンタのキャリジ送り機構に供せられ, 平均印字速度70字/sを実現している.今後は, リニアサーボモータの軽量化と高推力化, リニアセンサの高信頼度化等が, リニアモータ駆動によるキャリジ送り機構の課題となろう.
  • 八重島 公郎, 両角 宗晴
    1981 年 47 巻 8 号 p. 1000-1004
    発行日: 1981/08/05
    公開日: 2009/06/30
    ジャーナル フリー
    In mechanical variable-speed drives, the range of revolution ratio is one of the important performances, and it is desirable that the range is as wide as possible. However, among the mechanical variable-speed drives being put in practical use now, those which can change speed steplessly from normal revolution to reverse revolution including zero revolution (stop) are very few. The authors newly devised and manufactured a mechanical variable-speed drive on trial, which has the larger range of revolution ratio and is smaller in size as compared with conventional ones, besides, on the use of which, large limitation is not imposed. This paper deals with the design, trial manufacture, operation test and the derivation of the formula for calculating both the rotating speed and the efficiency of this variable-speed drive, and it was confirmed that this variable-speed drive can be put to practical use, and that the formula derived for calculating the efficiency is sufficiently useful for estimating the efficiency at the time of the design.
  • 大塚 二郎, 局 又太郎, 光永 聖
    1981 年 47 巻 8 号 p. 1005-1007
    発行日: 1981/08/05
    公開日: 2009/06/30
    ジャーナル フリー
  • 米津 栄
    1981 年 47 巻 8 号 p. 1015-1016
    発行日: 1981/08/05
    公開日: 2009/06/30
    ジャーナル フリー
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