含気マイクロカプセルを用いると非接触に超音波による圧計測 (PEPA) や高精度変位計測 (HsDSE) あるいは血流やカプセル自身の流線描出 (2D-MTI)などの計測が可能であり, その素材や粒径を選択すれば任意の共振周波数を設定できることを実験的に示し, これをDDS-carrierに応用すると薬物の種類に関係なく制御を行い得る可能性を紹介した.
生体内で安全に用い得る含気マイクロカプセルの直径はAlbunexと同様に数μm (1～8μm) であるが, 都合のよいことにこのサイズでの理論的実験的に予想される共振周波数は約1～7MHz程度と, 生体内における超音波減衰特性と画像分解能から必然的に決定する医用超音波計測での使用可能周波数帯域と偶然にも一致する.
薬物移動と濃度あるいは圧分布をモニタし, それらに基づいて薬剤放出を行うDDSは, あらかじめプログラムされた通りに薬物放出を行う従来の化学的なDDSに対し, 物理的に外部からコントロールできるマイクロアクチュエータである.定量的計測・制御に使える生体用精密マイクロカプセルは現時点では未完成であるが, Albunexの出現で大きく前進したごとく, 近い将来高精度な生体用マイクロカプセルが完成することと思われる.

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An air bearing lead screw and nut have been developed for application to ultra-precise positioning over long strokes. The design features are : (1) Porous restrictors made of ceramic materials with surface plating are applied to the flanks of the nut threads. (2) The thread profile is square to improve its machining accuracy and this minimizes bearing clearance. Performances of the air bearing lead screw and nut were examined with a fully air-lubricated one-dimensional linear table. Primary results for a lead screw with a nominal diameter of 25mm are : (1) The axial stiffness is over 30N/μm with 0.5 MPa supply pressure. (2) Precision of the nut linear motion is evaluated to be 5 nm. (3) Lead accuracy is improved more than 10 times compared to the machining accuracy of lead screws. These results demonstrate that the air bearing lead screw and nut is a practical approach for micropositioning with ultra-fine accuracy.

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A new solid-type end mill is the up-to-date cutting tool made from supertough cermet material, which was developed for end mill. This cermet has TiC and TiN for its main ingredients and equals cemented carbide in elastic modulus and its heat conductivity is lower than one tenth of that of cemented carbide. The tool life of cermet end mill in optimum cutting condition proves to be about two times as long as that of cemented carbide one. This end mill ensures surface roughness of 1μmR_max which is equal with ground surface one. Since cermet end mill is so small as φ2-12mm in tool diameter, restriction from machine tool side at cutting speed and feed rate, also, is considered, but careful consideration is paid to tool design, so that stable cutting could be capable at the cutting speed 30-100m/min.

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The Finite Element Method (FEM) is an excellent simulation tool in the Computer Aided Engineering (CAE). It is indispensable to a new product development because of its superiority in wide usability, low computation cost and high accuracy. However, it is difficult to utilize the FEM well enough without experts in the FEM. Therefore, a consulting system for the FEM is required to help beginner to master it by himself. Concretely the following fields in the FEM require a consulting system : (1) modeling, (2) mesh generation, (3) output inspection and a total consulting system for the FEM “FEMHELP” are developed. In this paper, the necessity and outline of the FEMHELP system are shown.

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コーナ部のフィレット形状を, 簡潔な原則により, 対象曲面の種類, 頂点での稜線数丸めの半径にかかわらずC¹連続で統一的に処理し作成するアルゴリズムを示した.物理的なものに対応したローリングボール法により定義したので, 現場で製作されるものとよく一致する自然な形状が得られた.今後は, 球が面に接する場合に加え, 稜線に接する場合のフィレット曲面生成法を開発し, 形状モデリングシステムへの組込みを図る.

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Microcutting of AFRM (Alumina Fiber Reinforced Metal) are performed with SEM direct observation method. The purpose of this study is to make clear the cutting mechanism of AFRM and the fracture of fibers at the plastic deformation zone of the orthogonal microcutting. Since AFRM shows an obvious anisotropic strength depending on the direction of fiber axes, cutting direction are classified by the fiber angle. Summary of the results are shown below. (1) The fracture of fibers in microcutting with carbide tool are caused by shearing, tensile and bending forces. (2) In fiber angle 30° and 60°, the direct collision of fibers with cutting edge of tool were observed with high frequency. In these cases, fibers were fractured by the shearing force. (3) In another fiber angles, fibers were fractured by the bending forces after the severe bending deformation. The amount of deformation in fibers became larger in the case of fiber angle 90° and 120° with an extensive overcut. This enhances difficulties in the exhaust of chip and worsens the surface finish. (4) The deformation zone of the orthogonal microcutting with diamond tool was found to decrease by approximately one-half comparing with carbide tool. This can be attributed to the low friction coefficient between the rake face and a sharp edge of the cutting tool. (5) Four typical cutting mechanism have been proposed by the results of the direct observation of microcutting of AFRM.

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This paper presents some experimental results on the mechano-chemical polishing of bulk polycrystal ferrite as well as polycrystal ferrite laminated with other materials. A polishing plate made of tin is used with a polishing fluid chemically active to ferrite such as hydrochloric acid. Using the mechano-chemical process, the stock removal rate can be increased and the damaged layer of the polycrystal ferrite decreased, in contrast with those in the mechanical polishing process. For laminated ferrite, the micro-steps are substantially formed on the polished surface made of different materials. This feature is utilized for finishing the air bearing surfaces of multi-channel magnetic heads, when an electrochemical action is added to mechanical polishing, in order to compose the local cell between a ferrite and either a polishing plate or a laminated material.

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試作したダイヤモンドコーテイング工具を用いて過共晶Al-24%si合金の切削実験を行った結果, 次のことが明らかになった.
(1) 窒化けい素セラミックスを基体にしたダイヤモンドコーティング工具は, 切込みが0.2mmとわずかでも切削距離が大きくなると膜の剥離が起こる.
(2) 焼結ダイヤモンドを基体にした場合では, 膜の剥離が生じず, 摩耗もほとんど観察されないので, 切削工具として十分に使用可能である.
(3) 基体に窒化けい素を用いた場合と, 焼結ダイヤモンドを用いた場合の, ダイヤモンドコーテイングの付着性について考察できた.

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As the wire-EDM is based on discharge phenomena in a dielectric fluid, the eroded surface differs markedly from the base materials in many respects of physico-chemical changc caused by severe thermal actions with an extremely high cooling rate. The analyses about property changes of eroded surface are very important problem in relation to the erosion mechanism and quality of products such as surface integrity, some mechanical properties. The paper mentions the characteristics in degenerated zones due to wire-EDM, using ESCA (Electron Spectroscopy for Chemical Analysis) method which is very effective for analysis on extreme surface of 1-2×10^-3μm depth and chemical combination of elements. As a result, it was proved the existence of Fe oxide (FeO, Fe₂O₃), Cr oxide (Cr₂O₃) and its depth below surface. The density and thickness of wire electrode materials (Cu, Zn) on machined surface were sustained, and it didn't occur oxidization in those materials.

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正方形テーブル板の四隅を対角線方向に配置した円弧はりとオイルダンパで支持した除振テーブルを開発し, その水平方向と上下方向のばね特性および水平方向の共振曲線を理論と実験によって検討した.おもな結果は以下の通りである.
(1) 本除振テーブルの水平方向ばね定数は水平面内のどの方向にもほとんど同じ値をもつ.
(2) 水平方向および上下方向のばね定数はR, β, dの値によって大きく変化し, R, βが大きいほど, またdが小さいほど小さくなる.
(3) 円弧はり上部の剛体直線部の長さLおよびテーブル板の一辺の長さaの値は除振テーブルの水平および上下方向のばね定数の値にほとんど影響を与えない.
(4) 本除振テーブルの水平方向共振曲線は加振方向に関係なく似たような共振曲線となり, 加振方向以外の連成振動はほとんど生じない.
(5) オイルダンパの制振効果は加振方向によってやや異なる.

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アーク放電プラズマジェットCVD法によって合成したダイヤモンド薄板をYAGレーザ照射によって切断加工および平坦化加工を試み, その加工特性を調べ以下のことがわかった.
(1) レーザ照射エネルギー密度を調整することによってダイヤモンドの切断加工を行うことができた.エネルギー密度が小さくて切断加工できない場合には, 無定形炭素, 結晶粒界や欠陥部, ダイヤモンド粒の順に選択的にガス化して除去されるだけである.
切断加工の進行する条件では黒鉛化あるいはガス化が同時に進行してダイヤモンドが除去され, クラックのない良好な切断面が得られる.しかし, アルゴン雰囲気中ではダイヤモンドが黒鉛化して切断溝周辺及び溝内部に付着する.この黒鉛の付着量は酸素濃度が高くなるほど減少し, 酸素分圧700torr以上で付着物は観察されなかった.
(2) レーザビームのピークパワーを大きくするほどアスペクト比の大きい切断溝が形成され, 空気中, 1回のレーザ照射で幅30μm, 深さ120μmの切断溝が得られる.この照射を繰り返すことによって, 幅30μmで深さ800μm程度の切断が可能であった.
(3) レーザ照射角度を変化させることにより任意の傾きを有する切断面が得られる.そして, ダイヤモンド薄板表面と平行に照射することによって表面粗さ3μmR_max程度の平坦化加工ができた.

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As one of the difficult-to-machine materials, austempered bainitic spheroidal graphite cast iron (FCD 1000 A) have been machined so far only by grinding. In the present study, cutting of the FCD 1000 A was tried using CBN tools. Cutting performance of the tools was investigated through determining the optimum combination of condition for cutting and binding phase for the tool materials. For fine cutting of the FCD 1000 A, the optimum cutting temperature was determined as 1 100 K and the best material for the binding phase of CBN tool was TiC from both tool life and surface roughness points of view. From the temperature dependence of flank wear rate, wear behavior of the tool could be classified into two temperature regions, A and B. In the region A, a scratch mark was abundantly observed on the wear surface of the tool due mainly to microspalling of c-BN particles. In the region B, it was significantly observed that the tool wear was controlled by falling-off of adhering particle from the cutting edge.

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The study deals with the automatic measuring path generation of 3-dimensional measuring machine (3 D-CMM) with 5 degrees of freedom. The 3 D-CMM consists of the Cartesian coordinate structure and a touch probe with 2 rotational degrees of freedom. The measuring path is automatically generated in off-line on the basis of CAD, taking account of the collision between the touch probe and workpieces. The measuring path is converted to the actual one by matching the CAD data with the image of workpiece being arbitrarily set on the 3 D-CMM. The system enables the measurement without changing the setting of workpieces, which remarkably reduces the measuring time.

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This report discusses subjects and countermeasures in order to apply the stripe pattern projection technique to the automatic focusing equipment used in microscopes. The effects of wafer circuit patterns, wafer defocus and illumination system on the detected signal wave of the projected stripe pattern are analyzed. A technique to minimize the detection error of the stripe pattern contrast by eliminating the influence of the circuit pattern on the stripe pattern image is described. Also, an illumination technique to secure a uniform stripe pattern image and a detection technique to improve contrast detection accuracy are discussed. Using these techniques, a repeatability of ± 0.6μm (3σ) and an accuracy of ±1.0μm (3σ) in automatic focusing have been achieved.

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The calculation formula for zooming FFT, by which zoom FFT analysis can be carried out on a personal computer without any special FFT instruments, was derived by applying the same procedure that the Fast Fourier Transform was derived from discrete Fourier transform. According to the derived formula, a BASIC program of zoom FFT was coded, and was applied for analyzing the gear transmission errors measured on two tested gear pairs. By selecting a zoom ratio equal to the lowest common multiple of their gear- and pinion-tooth number devided by the gear tooth number, their gear- and pinion-low harmonics were distinctly separated and extracted without piket fence effect. And the amplitudes of the pinion low harmonics corresponded well with the hearing noise levels of the tested gear pairs.

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An approach was given to estimating straightnesserror curve using identification technique and Kalman filter in a previous short paper. This approach can compensate accidental errors which are mixed to the measuring values from displacement sensors when a serial three point method is used. In this paper, the following facts are revealed by simulation and some experiments. (a) This approach is a match in measuring accuracy for a serial multi-point method which uses four displacement sensors. (b) This approach is superior in accuracy and repeatability to a serial three point method. (c) This approach shortens the computer processing time to 1/10 comparing with a serial multi-point method.

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This paper deals with a failure diagnosis of a pneumatic directional control valve used in automated production systems. The valve vibration is monitored by an accelerometer : Six parameters characterizing the vibration data are extracted, and fed into multi-layer neural networks to solve four types of diagnosis problems. It is shown that the neural network approach is useful for the failure diagnosis, yielding low failed-safe and low failed-dangerous probabilities. Neural network structures are analyzed through Boolean expressions summarizing relationships between two successive neuron layers. These expressions are obtained by noting that, for learning patterns, occurrences of discrete failure events behind continuous network input parameters are known. For each neuron, its function can be clarified by the structure analysis; irrelevant neurons can be identified and removed without degrading the diagnosis performance; the neural network for a diagnosis of foreign material around a spool utilizes a majority voting mechanism, and attains a 50% reduction of incorrect answers compared with a linear diagnosis. A conjugate gradient followed by a variable metric method is demonstrated as an effective learning algorithm.

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High-speed and heavy-duty grinding of non-circular workpieces generally requires high rigidity of the overall mechanical system including the wheel feed system and the workpiece rotating system. Conventionally, hydraulic systems, such as the hydraulic copying mechanism and hydraulic servo mechanism, with which high power can be obtained relatively easily were mainly adopted as the drive system for highly rigid machine tools. However, electrical servo mechanisms capable of outputting high power are gradually being adopted by NC system. This paper discusses two problems; (1) improving in profile interpolation accuracy and (2) improving in servo error in high-speed grinding. Both problems are related to control technology and both will arise when an electrical servo mechanism is adopted for high-speed high-accuracy non-circular profile grinding. Solutions are offered for both problems. The solutions proposed by this paper are high speed, automatic generation of minimum linear interpolation data, the feed-forward control method, and the profile error compensation method. Prototype test equipment has been made to evaluate the feasibility of the solutions and to check how they can be adopted.

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The three-point methods such as the summit method and the rider method give convenient way of assessing circularity. Especially, the method by the use of three displacement detectors is a promising technique to separate precisely the circularity profile of a workpiece from apparent runout on a machine tool. Several in-situ circularity measuring systems based on this method have been developed so far. In these systems, however, relative angles between three detectors are not necessarily determined in a reasonable way. In this study, the performance index of the detecting angles has been derived by applying the law of error propagation to the method and the most reasonable angles have been determined by optimizing the performance index. In addition, by utilizing the performance index, generalized n-point method has been developed and its effectiveness in improvement of measuring accuracy has been verified analytically and experimentally.

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There are many types of defects in wood, some of which reduce strength of structure parts or spoil the appearance of furniture parts. To make efficient use of valuable wood free from such defects, it is desired to develop an automated inspection system which is able to locate the position and extent of each defect present and to identify the type of defect at each location. In this paper, we propose an automatic inspection method to detect and discriminate surface defects in wood. The essential points of the method are as follows : Input gray level image of testing wood is divided into a number of regions and several tonal property measures are extracted from image of each region, and fuzzy clustering technique is adopted for detection and discrimination of surface defects. Applying the proposed method to inspection tests of actual lumbers, we obtained the following results : (1) Defect detection can be achieved almost completely. (2) Discrimination rate ranges from 25 to 82% depending on the type of defect, and this indicates that more research is needed.

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A new type of hologram interferometer for null-testing and measuring a paraboloidal mirror configuration is proposed. In the interferometer a hologram causes a spherical reference wavefront which interferes with a spherical wavefront reflected by a paraboloidal mirror under test. The method to calculate the amount of configuration error of a paraboloidal mirror from the interferogram is also proposed. Almost straight and equally spaced tilt fringes obtained in the experiment for a commercial on-axis paraboloidal mirror shows the interferometer is useful.

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