原子レベルの分解能と高い三次元位置決め能力を有するSTMは,試料を非破壊で三次元計測できることが従来の測定装置にない大きな優位性である.微細加工パターン等の測定結果から,格子の溝交差部における深さ50nmの急峻な構造についてもXY面内分解能10nm以下,Z軸方向分解能1nm程度で三次元計測が可能となり,深さ方向の情報を有する三次元計測では従来の走査型電子顕微鏡を凌駕する見通しが得られた.STM像は等高線表示等によって微細形状を三次元情報として把握できるためパターン測長,段差計測が容易であり,マイクロエレクトロニクス分野のみならず広く微細加工表面の評価装置として有望である.

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ガス中や液体中の実験は,物質の表面を原子的レベルで制御して行うことが可能であり,ガス中や液体中でも原子が見られるSTMの測定対象として非常に興味ある系である.
本研究では,STM測定のための電気化学セルを製作して,電気化学的処理によるSTM像の変化について調べた.その結果,STMで拡散律速型の電気化学反応を時間的・空間的に分解して測定出来ることが明らかになった.このことは,電気化学反応の原子的レベルでのその場観察と分析・制御が可能な走査電気化学顕微鏡の開発の可能性を示している.このような顕微鏡が開発されれば,真空中での薄膜形成や薄膜加工と同じようなことが液体中でも可能となると予想され,液体中でのみ製造できる新しい材料の開発も可能になると期待出来る.

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機械加工のできるロボットの現状は,被加工物が単純形状のものを除き,コンピュータの支援なくしては実現は遠く,FAの一員となるためには,マシニングセンタ等の工作機械用CAMの研究と同様に機械加工ロボット専用のCAMの研究が望まれる.
それには,個々の形状モデルを正確に加工できる技術と実績をつくることから始めなければならない.
また,従来の人間の手作業は,付加価値の高い作業ばかりではないので,ロボットの導入に当たっては,経済的な面でも制約を受ける.従って,シンプルにして安価な適応範囲の広いロボットが要求されよう.

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In response to the increasing demand for press tools, a compact and practical CAD/CAM system for progressive dies, one of the most complicated types of press tools, has been developed. The features of this system are: (1) designing can be easily accomplished just by inputting the geometrical data of the strip and die layouts, and (2) CAM information can be directly extracted from the CAD information. In developing this system, a new model for die construction has been determined by studying the design process. An algorithm and data file needed for automatic tool selection and calculation of machining conditions and tool paths have been completed from the data obtained by using this model. To analyze the usefulness, many practical studies have been performed, and it has been found that the total period for design and manufacturing is reduced to about 1/5 the time previously required. This method can also be applied to many other types of press tools, such as compound dies, single dies, and transfer dies.

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本報では,ダイヤモンド研削式NC非球面レンズ研磨機と3軸双子型スモールツールの開発とその経緯について概説し,新型の2軸偏心量可変型スモールッールについて,その原理,構造,機能を詳しく述べた.次いで,これによる非球面研磨の検証として輪帯研磨,球面の放物面化について述べた.
非球面製作技術の研究は最近著しく進歩し,非球面の用途も拡大されてそれにふさわしい新しい方式が次々と実用化されつつあるが,人工衛星搭載用リモートセンシングカメラや天体望遠鏡のような大型で高精度の光学系への対応はまだ不十分と思われ,今後も精力的な開発努力が必要である.

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Vibrations and noises of gears consist of the average component and the fluctuant one. The former is the component which always appears in each tooth meshing. In general, this component consists of the meshing frequency and its harmonics. The latter is the component which fluctuates about the average component and is caused by the error of gears, torque fluctuation, and so on. In this report, the extraction of this average component by using a method of moving averages is described. This method is very effective for extracting the average component of gear noises or gear vibrations. The effectiveness of this method is shown theoretically and experimentally.

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小ねじ強度試験機を試作し,強度差を与えたM2十字穴付きなべ小ねじの強度試験を行った.得られた特性値を用いて,小ねじ強度及び検出力に影響する因子を調べた結果,次のことが判明した.
(1)強度試験の結果からねじ面の潤滑は最大締付けトルク,軸力及びトルク係数に,座金の有無は締付けトルク及びトルク係数に,座面の潤滑は締付けトルク及びトルク係数に,雌ねじ材質は軸力,ねじトルク及びトルク係数にそれぞれ影響を与えるが,Crめっきの有無はほとんど影響しないことがわかった.
(2)小ねじ強度の検出力から,小ねじの強度試験を行うための最適条件をSN比ηを用いて判断することができた.すなわち,最大締付けトルクにはねじ面のマシン油潤滑,Crめっき小ねじ,S45C雌ねじが高い検出力を示したが,最大軸力に対しては影響する因子が求められなかった.また,弾性限に対する締付けトルクに対してもマシン油潤滑及びCrめっき小ねじの使用が検出力が高く,軸力に対してはねじ面及び座面のマシン油潤滑とS 45 C雌ねじの効果が大きかった.
(3)特性値の誤差を比較するため,変動係数の大小を表現するパラメータη'を用いて解析を行った.締付けトルク及び軸力は最大値及び弾性限値に対してともに変動係数で10%前後であるが,ねじトルク値は約2倍大きい変動係数を示した.
(4)新しく開発した試験機を用いた時のねじ強度の測定誤差を検討してきたが,従来の試験法に比べて精度的にも十分妥当性があると考えられる.

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This paper describes an experimental investigation of the grinding mechanism in a highwork-feed-rate electrolytic grinding method. An idealized tool consists of a single diamond tool and a copper electrode in substitution for the conductive grinding wheel. The influence of electrolytic action on single diamond cutting force components in SS 41 and Al-Cu-Si alloy are investigated and discussed using the cutting force equations reported in the previous paper. Summary of the results are shown below. (1) Cutting force components consist of both chip formation and ploughing force in the case of single diamond cutting. (2) Cutting force compo-nents in SS 41 decrease in proportion to the increase in the applied electrolytic amount. This may be caused by the reduction of chip formation force due to the decrease in actual cutting depth of cut. Ploughing force and specific grinding force are held constant even by the applied electrolytic action. (3) Cutting force components in Al-Cu-Si alloy also decrease with increase of the applied electrolytic amount. As the applied electrolytic action in this alloy induces the preferential dissolution of hardened precipitation particles, the specific grinding force decreases remarkably, thereby causing a decrease in the chip formation force. Material softening by the preferential dissolution increases the ploughing force. (4) The propriety of the proposed cutting model is ascertained by the experimental study of cutting time in an electrolytic single diamond cutting.

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This paper describes a new device which can automatically measure the lead error at the cutting edge of threaded cutting tools such as gear-hobs and taps. Firstly, a new precise main spindle with a precise rotary scale, a new-type photoelectric feeler, and an angular position detector for cutting edge are developed. Secondly, the non-contact-type automatic measuring machine is produced, combining them with a tool makers' microscope, laser length measuring system and a microcomputer. Thirdly, the program for the control of the machine and for the measurement are developed, and the cumulative lead error and the cumulative dividing error of the cutting edge are computed from the detected values by the microcomputer and recorded by a printer or a plotter. Finally, in order to investigate the accuracy of measurement in this machine, the experiments are carried out. The main results are as follows: (1) The precision of measurement for the lead error in the gear-hob is 0.16μm for repeatability in standard deviation. (2) The detective precision for the angular position of the cutting edge is about 10'' for repeatability in standard deviation.

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This paper describes the change in the vibration of the teeth in the process occurring the initial surface failures of gear teeth. First, the torsional vibration characteristics are analysed of a gear pair with several profile errors and frictions between the teeth. The maximum of the tooth root stress is found to be desirable for observing the vibration characteristics connecting with the tooth failure. Second, the pitting test is carried out to find the typical change in the maximum of the tooth root stress during the test. The pattern of the typical change is as follows: The maximum of the tooth root stress increases gradually with the number of load cycle, then reaches to the peak because of its decrease due to the pitting of the tooth.

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Even when the temperature of the ball screw reaches steady state, the change of its distribution is repeated as the nut goes and returns. In this study, the repeated change is numerically analysed by a difference method on several idealization, where the screw shaft is replaced by a solid cylinder and the nut is replaced by a hollow cylinder. This thermal phenomena is treated as a contact problem between two cylinders. The following results are obtained: (1) The temperature of the screw shaft is higher just around the nut. Therefore, it is expected that the forced cooling of the screw surface near the nut is effective. (2) There is almost no temperature gradient in the radial direction. Therefore, there is a possibility that the heat transfer of the ball screw can be regarded as one dimensional problem.

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The various phenomena generated in the machining process are generally recognized for the quality control purposes on the basis of the engineering measurements. However, the skilled machinist perceives the premonitory symptom of the unusual grinding phenomenon by his excellent sense of hearing. The present paper, therefore, was an attempt to devise new monitoring methods which utilize positively the acute sense of the human instead of the customary methods. Our study has led to one very significant conclusion : There is a very strong possibility of the diagnosis of the redress life, because the sensuous value perceived by the human can be rank-ordered and discriminated by means of the technique of pattern classification using fuzzy algorithm.

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The purpose of the paper is to theoretically calculate infeed of grinding wheel for forming a cambered workpiece such as roll in traverse grinding. The infeed of grinding wheel has been analyzed considering various residual stock removals, wheel wear, the profile change of cutting surface of wheel caused by wheel wear. Then it is made clear that cambered workpiece can be ground with NC-grinding machine. The distributions of stock removal rate, grinding force and wheel wear rate on cutting surface of wheel are calculated.

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The paper is concerned with the increase of endurable pressure in machining of a new lapping wheel named ''Liquid-Bonded Wheel''. The bond strength of this wheel is smaller than that of conventional grinding wheels. But endurable pressure of this wheel becomes high enough to withstand the mechanical shock of bumping to the workpiece and machining by employing some technique as follows. (1) Improving the angular accuracy of the axis of the main spindle of machine. (2) Using finer abrasives for increasing the contact points by unit volume of stacked grains in the wheel. (3) Using combination in still finer grains with the fine grains for increasing the density of the mixture. The wheel employing these technique has the endurable pressure of about 1 MPa in machining. Moreover, packing the vessel uniformly with abrasive grains may be important, for an uneven packing may deteriorate the flatness of the working surface of the wheel, and the flatness may influence the geometrical accuracy of the finished surface of workpiece. The wheel packed uniformly with grains is manufactured by covering the bottom of a mold with some annular plates.

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This paper deals with the life of various tools to clarify the machinability and optimum tool materials in cutting of sintered carbons with high hardness. Furthermore, the behaviors of the tool wear are discussed from the view points of cutting forces, chip geometries, surface roughness and vibration characteristics, such as cutting frequency and amplitude in chatter vibration cutting. The obtained results are as follows. (1) The tool is worn by the abrasive action in cutting of sintered carbons. Particularly, CBN and ceramic (black) tool are worn. Sintered carbide (K grade) and sintered diamond tool have a long life in tool materials used. (2) A decrease of the wear rate of the tool relief face in chatter vibration cutting and in increasing of the cutting speed depends on a decrease of the contact number between tool and work and an increase of relief angle, which is varied by vibration characteristics.

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Single-point diamonds are used to scratch the surfaces of HP-Al₂O₃, HP-Si₃N₄ and S-SiC. When depth of cut is about 2μm, the diamond tips are worn by either the single-plane or the double-plane or the microfracture type. The wear rate of S-SiC is the highest and then HP-Si₃N₄ and HP-Al₂O₃ in turn. When depth of cut is larger than 2, um, the adhesion is remarkably severe. The adhered layer has a tendency to become thinner as the scratching speed increases. It exhibits swelling and partly flaking repeatedly in the scratching process.

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This paper deals with a reliability analysis for determining an abrasive belt life by the size of wear land formed on the cutting edges. The experiment was carried out under the following conditions: the grinding speed is 480, 960 and 1440 m/min, and the contact pressure is 17, 35 and 50 kPa, respectively. The distribution of the land was measured at the desired grinding time up to 3600 seconds using a new developed instrument. The experiment above was repeated by changing grain size, stiffness and grade of the belt. It was found that the distribution of wear land is fitted to the Logarithmic normal model. The reliability function and the hazard rate of abrasive belt life for quality of surface finish are also derived.

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In this paper, tool life in wafer rotation grinding is compared with that in creep feed grinding. Then the trial to improve the tool life is done by means of doing dressing and grinding simultaneously. The main results obtained are as follows: (1) Tool life in creep feed grinding depends on increasing of surface roughness and normal grinding force and changing of outlook of ground surface. And, in this case, it is about 100 wafers of 4 inch size. (2) Tool life in wafer rotation grinding depends on increasing of normal grinding force, and, in this case, it is 10-15 wafers of 5 inch size when dressed by PVAR 600, 60-70 wafers of 5 inch size when dressed by GC 1000 H. (3) Surface roughness and normal grinding force are maintained nearly constant by means of each time dressing and intermittent dressing. And these dressings are done during grinding, so there is no loss time for dressing. Therefore the problem of tool life can be resolved. (4) Wear of grinding wheel by dressing in wafer rotation grinding is nearly equal to that in creep feed grinding.

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For the purpose of contributing to the advanced technology of fabricating metal molds and dies with curved surfaces, the computational algorithm has been developed for generating tool paths suitable for high rate machining using the cemented carbide toolings. The software incorporates the high speed algorithm developed by a preceding study of the authors for computing the intersections and checking tool interference among multiple curved surfaces. The prototype CAM system automatically generates the tool paths as the rough cutting tool path, contour line tool path, and scanning tool path which continuously transfer on to the next element surfaces. Cutting tests have been performed by using the prototype CAM system connected to a machining center, and demonstrated the effectiveness of the high speed and high accuracy tool path generation and the real time machining of the curved composite surfaces.

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