精密機械
Print ISSN : 0374-3543
30 巻, 357 号
選択された号の論文の9件中1~9を表示しています
  • 林 大九郎
    1964 年 30 巻 357 号 p. 763-769
    発行日: 1964年
    公開日: 2009/10/08
    ジャーナル フリー
  • 小宮 宗治
    1964 年 30 巻 357 号 p. 770-778
    発行日: 1964年
    公開日: 2009/10/08
    ジャーナル フリー
  • 熱損傷と工具摩耗の関係
    杉田 忠彰, 山田 巌
    1964 年 30 巻 357 号 p. 779-784
    発行日: 1964年
    公開日: 2009/10/08
    ジャーナル フリー
    According to the experimental results, it is evident that ceramic face milling cutter do not receive a fatal damage as a complete fracture by the thermal cracks which produce in the cutter, but tool wear of the cutter is promoted by these thermal cracks.
    Comparing the tool wear in continuous cutting (turnning) with in intermittent cutting (face milling), the latter is remarkble. And, it is found in some microscopic observations on the wear surface of the cutter that the increasing wear affect with falls of many alumina grains from the tool surface. The more cutting condition in the intermittent cutting is severe, the more falls of the grains are remarkble, and also characteristics of the wear approch to it in the continuous cutting when the cutting condition is light.
  • せん断機構の力学的解析
    北条 英典
    1964 年 30 巻 357 号 p. 785-793
    発行日: 1964年
    公開日: 2009/10/08
    ジャーナル フリー
    Stress distributions in the rectangular region enclosed with parts compressed by punch and die were analysed for the process of elastic deformation in shearing, employing the shearing model which was induced from the previous reports. Assuming that the stress distributions had no change until the early stage of appearance of first micro-cracks, and using failure condition for plastic anisotropic body, angles of first micro-cracks (α) and reduced shearing forces (kc) at the moment of appearance of first micro-cracks were calculated and they were compared with each observed values. Thus, it was confirmed that the shearing model adopted here was suitable for shearing mechanism.
    The results obtained are as follows :
    (1) The values of α increase and the values of kc, decrease as the rectangular region sheared by tool becomes smaller, and applied forces concentrate at the cutting edges.
    (2) The values of α and kc, decrease as the side force increase.
    (3) The values of α increase and the values of kc decrease in the case where normal tensile stress act on the vertical sections of the sheared part.
    (4) Distributions of stresses and α along the center line of the clearance between punch and die have the transition points near the surface layer of the sheared part, in which points values of α are minimum and first micro-cracks begin to appear.
  • 各種焼入条件に伴う硬化層の適性
    小川 喜代一
    1964 年 30 巻 357 号 p. 794-802
    発行日: 1964年
    公開日: 2009/10/08
    ジャーナル フリー
    This study is to find suitable flame-hardening conditions and also to see the wear resistance of metal by using as a testpiece Ca Kugelpraphite Gusseeisen flame-hardened by progressive hardening method.
    The flame-hardening has so far been known as comparatively easy method, but is now being recognized as a reasonable method of hardening because the direct measuring of surface temperature has been made possible recently by the appearance of Milliscope and by the progress of hardening equipments in western countries.
    In this study, we observed the quality of hardened layers and measured the hardened degrees of surfaces under the various suface temperatures made by changing the Feed Speed, Gas Pressure and Pre-Heating conditions of Acetylen-Oxygen Gas. Thus, we got the suitable flame-hardening conditions of Ca Kugelpraphite Gusseeisen and made actual measurings of the wear-resistance.
    From these investigations, we understand that comparatively low degrees of temperature for 800°C-830°C are good for hardening in the mechanical quality as well as in the wear-resistance.Also, we got a conclusion that the flame-hardening is better than Salt Bath Nitriding method of the same cast iron testpiece when compared in the wear-resistance.
  • 吹付け距離と被冷却物形状の影響
    山本 明
    1964 年 30 巻 357 号 p. 803-808
    発行日: 1964年
    公開日: 2009/10/08
    ジャーナル フリー
    To get informations on the application of mist cooling, effects of blow distance and shape of a cooling object are discussed by measurement of the local heat transfer coefficient α. Effect of cooling object shape consists chiefly from the effect of blow angle against the surface and that of gravity upon liquid flow spreading over the surface.
    (1) When mist turns into liquid flow on the outside of the scope which mist covers over the surface, strong cooling power can be get. Rate of this re-liquidification of mist comes up to 8090%.
    (2) When the mist flow is under increased liquid flow rate and in the situation stated in (1), cooling area expands almost geometrically as blow distance increases. The more heat is carried away, for the maximum cooling strength (αmax) remains neary the same.
    (3) Effect of gravity accompanied with inclination of the surface brings about unsymmetrical distribution of α and a change of cooling scope.
    (4) With inclination of blow angle against the surface, cooling scope comes up an oval and expands. Heat quantity that flow can carry away does not so much decrease.
  • 田中 義信, 津和 秀夫, 河村 末久
    1964 年 30 巻 357 号 p. 809-815
    発行日: 1964年
    公開日: 2009/10/08
    ジャーナル フリー
    Microstructure and the distributions of cutting edges on the grinding wheel dressed by diamond, crush-roller, and the other grinding wheel are investigated.
    The results are as follows;
    (1) when dressed by diamond and crush-roller, almost of the top surface of cutting edges are formed of shellyenevenness, but dressed by grinding wheel, they are formed of flat surface like worn surface.
    (2) when dressed by diamond, about 7090 per cent of grains remain on the working surface, so that cutting edge spacing becomes about 2 mm for a grinding wheel of A46. But, dressed by crush roller, many grains fall off, and the spacing becomes larger.
  • 全体加熱した丸棒被削材を旋削したときの形状誤差
    一宮 亮一
    1964 年 30 巻 357 号 p. 816-821
    発行日: 1964年
    公開日: 2009/10/08
    ジャーナル フリー
    The shape in which the whole-heated cylindrical work with same diameter is machined with lathe is not always cylinder with same diameter depending on the temperature distribution of the work by natural cooling. Then, in this paper, the theoretical equation for the shape error of the work which is machined after whole-heating is reduced and the comparison of numerical and experimental results are discussed.
    These results lead to following conclusions.
    (1) The diameter of the work which is whole-heated and machined is maximum at the end of machining and also minimum diameter is observed. The shorter the time of natural cooling, the position of minimum diameter approaches to the side of starting and longer the time, the position of minimum diameter comes to the middle.
    (2) The difference of maximum and minimum diameters is large when the time of natural cooling is short and it shows maximum when the time is zero.
    (3) Experimental results at 400°C of work temperature and numerical results coincide comparatively.
  • 太田 信之, 大井 真次
    1964 年 30 巻 357 号 p. 822-828
    発行日: 1964年
    公開日: 2009/10/08
    ジャーナル フリー
    This paper describes the method of flatness measurement of surface plates by means of a straight edge and an indicator with 0.001 mm graduation.
    The straight edge is supported with two gauge blocks on the surface plate. The measuring spindle of the indicator moving along the straight edge is in contact with the surface plate, in order to measure its straightness in any direction. In the preceding papers, it was discussed how the deflection of straight edge is minimum. In this paper, the results are applied to the flatness measurement of surface plate. The experiments show that if the straight edge is supported on two points according to the invented method, the flatness of surface plate smaller than 1000 mm×1000mm is measured within accuracies specified in JIS (f.i. 1 st grade 13μ and 2 nd grade 32μ in 1000 mm × 1000 mm) by this method.
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