Today we have serious position of the environment by factory development. We have to establish the development to meet the environment as soon as possible. As to cutting although dry process is ideal but it has problems in insufficiency of lubricant and cooling. Then cutting is performed in nitrogen gas that can control the generation of heat and keep it cool. In this research, we apply nitrogen process to end mill cutting in machining center. By comparison with dry process, we examine the effect of lubricant by nitrogen against oxidization layer. Finally, we verify the advantage of nitrogen process.

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Oil-mist or fume is generated in the near-dry machining process. Recently, the machining process is conducted in the closed machine, arid such small particles are evacuated outside with the mist collector. In this study, the amount of the small particles of oil mist and fume was measured in the working environment under various conditions. It was shown that the air pollution can be avoided by using the aid of mist collector with high performance filter especially very small particle smaller then 0.3μm. Also the amount of the mist particle which the machine operator is exposed when the machine door is opened at the work piece change. It was shown that using the mist collector with appropriate performance can prevent the discharge of the particles outside of the machine.

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In this case of using mist cutting(MQL), many problems are remaining. For example,oil mist may diffuse into working area and enter the woker's lungs,this phenomena may cause the health hazard. To solve these problems,we have studied a new cutting liquid which acts as lubricant in cutting and then it completely evaporates and does not remain on the workpiece. In this study, we indicated that the fundamental cutting characteristics of an aluminium alloy and a steel by applying no dregs oil mist. Moreover, we compared it with the characteristics of commonly used MQL methods and dry cutting.

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A new ecological method to supply a minimum amount of lubricant has been proposed, in which relatively large water particles, covered with a thin oil film. This new method is called OoW (Oil Film on Water Drop Gutting Fluid). In this report, the lubrication and the cooling performance of the OoW are investigated. The force are recognized the same value in the four cutting.fluid by friction and wear test machine. The lowest temperature rise of material is OoW. In cutting force test, OoW is appeared the best value by milling test on MC.

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An ultraprecision positioning table system is one of the most important components in nano manufacturing systems. This paper describes an ultraprecision XY positioning table system newly developed. The table is levitated by aerostatic bearings and driven by voice coil motors arranged symmetrically about the driving axes. The table is, consequently, free from the non-linear behavior and the direction dependency. The positioning capability of the developed system has been verified through a series of nano-positioning experiments.

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We developed a reaction-free linear slide, Shuttle Unit, for high speed machining of linear micro-grooves such as diffraction gratings. Shuttle's speed is 1.2m/S and 3 cycle/S. It means 3 grooves with the length of 200mm are machined in a second. Reaction-free structure eliminates the effect of reverse motion of Shuttle with 10G acceleration. Shaper machining by single diamond crystal tool attached under the Shuttle, can make very precise grooves without burr. This time we tried machining more complicated grooves such as a groove which depth is synchronized with shuttle motion. This method can produce arbitrary pattern of grooves on the surface of work and add advanced optical function to it.

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Generally, in manufacturing of various parts of an ultraprecision machine tool, accuracy of a mother machine is not enough and tedious correction by scraping is indispensable. The purpose of this study is to investigate a possibility to design an ultraprecision mother machine which can produce machine parts of an ultraprecision machine tool. In this study, to obtain a higher accuracy independent of bed thickness or work size, active mounts are newly employed which can support the bed foot by push up or pull down forces and actively control the deformation of bed while the table traverses. From the results of simulations, it has been found that the active mounts are effective to improve the machining accuracy.

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A series of ultra-compact machines has been developed for small size work piece mass production in the automotive industry. It has been shown that these machines not only have necessary cutting capability, space, and energy saving characteristics, but also excellent dynamics and motion accuracy.

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A simple process to fabricate three dimensional microstructures on single crystal silicon is presented in this study. The area irradiated by focused ion beam (FIB) can be selectively etched in HF solution. Etching characteristics of irradiated area are studied. The etch rate of irradiated area increases with increasing dose over 3.4×10^<-5>C/cm^2. In addition, it can be also controlled by accelerate voltage. Finally, 3 dimensional microstructures can be fabricated based on these results, which indicates a possibility of industrial application as a novel 3 dimensional micro fabrication process.

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In order to study the effects of atmospheric molecules,a micro-cutting experiment of Fe was carried out with a mothod called one and a half round cutting in air,vacuum and N_2 environments. At the same time,the effect of oxidation was taken into account also. Comparing the change of cutting forces and observing the conditions of chips and scratches ,it was found that Fe seems to be more ductile in vacuum than in air and N_2. Finally, the wear of a diamond tool was discussed by measuring the ratio of C atoms remained on scratch surfaces with an EDS.

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In this study, we developed a diamond AFM cantilever for micro-to-nano scale machining. The diamond AFM cantilever is composed of single crystal silicon cantilever and a cutting edge with controlled tip shape. The former is fabricated by anisotropic etching of the single crystal silicon, the latter is taken out from diamond array tool. By using this cantilever to AFM machining for single crystal silicon, plane machining area was formed deep rectangular shape cavity. The depth of machining area was deeply with increasing normal load. And the chip of silicon was observed largely by SEM image. It was found that the diamond AFM cantilever was possible to machining with high efficiency and accuracy.

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The measurement system of dynamic accuracy of a multi-axis machine tool was developed in this research. This system is constructed with measuring parts using liner-scale which resolution is less than 0.1 micrometer and ceramics air slide and data analysis unit. Dynamic accuracy measurement was performed about the circle locus and straight-line locus in a simultaneous 5-axis control state, and this research has estimated the processing locus. In this report, dynamic accuracy adapting the technique of space positioning was measured, and the technique of evaluating the locus accuracy of a machine tool was developed.

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This paper deals with the analysis for motion error of the XY table of NC machine tools. When the table moves along corners, the overshoot or undershoot occurs due to the several mechanical and control factors. In order to clarify the mechanism, the simulation model of feedforward and feedback control block as well as mechanical block is used. By comparing the simulated and measured motion trajectory on an existing machine, it was found that the simulation could predict the motion errors at the corner, which can be interpreted into servo errors and mechanical errors.

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Optical measuring method for run-out of spindle with ball mirror and auto-oollimator is studied. However, the measuring result is estimated to include error by unevenness of reflectance on surface of ball mirror. Three-point method is one of measuring methods not to be affected by error of datum. Therefore, three-point method is introduced to remove the errors due to unevenness of reflectance. It is shown that three-point method is successfully applied to the optical measuring device for spindle rotation accuracy through ray tracing simulation.

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A run-out measuring instrument with capacitance displacement probe is widely used in industry. However, this measurement method has the defect that measurement result depend on a feature of measured object. Furthermore, attachment error between measured object and spindle is never detected in measurement at are section. In this paper, we compare the optical measurement by virtual V-block method which does not depend on a feature of a measured subject to 2-point method with capacitance displacement probe in view of measurement principle. And we show how to separate the attachment error from the run-out error of a spindle.

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Establishment of a supreme measurement technology for endmill cutting-edge profile as on milling-machine is indispensable to success the most precise milling work, such as die/mold and parts machining, recently. The aim of study is to develop a new measuring technique based on laser diffraction, which is called diffraction gauge method, to evaluate cutting-edge profiles of micro-endmill (φ≦500μm) with precision of better than 100 nm even though on-machine measurement. The measurement resolution was experimentally achieved to be 15 nm for a helical endmill and repeatability of ±50 nm with valid accuracy for new tools. In this article, the measurements on a sample of worn tool(φ300μm), which has curried out side milling of 4.4 m milling length on graphite with 40,000 rpm rotational speed, are presented. The experimental results verify that the diffraction gauge method is able to not only measure cutting-edge profiles of new micro endmills but also wear quantity of worn tools.

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This paper describes the static characteristics of water-lubricated high speed conical bearings. This type of bearing is intended to be applied to spindles for drilling small holes on printed circuit-boards. Pressurized water is first fed to the inside of the rotating shaft and supplied to recesses on the shaft surface through feeding holes. Water pressure is therefore greatly increased at the outlets of feeding holes due to the centrifugal force by shaft rotation. In addition, water pressure also increases by hydrodynamic effect of shallow recesses. The static characteristics are theoretically predicted and calculated results are compared with experimental ones. It was found that the proposed conical bearings can achieve both low power consumption and large load capacity.

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The Ribbon bearings that can reversibly rotate, which is one type of spiral-grooved thrust bearing, are supposed with an experimental verification in this paper. Liquid injection method is applied to the bearing to reduce the friction at start period. It means that the bearing is 'hybrid' one constructed by hydrostatic and hydrodynamic bearing. By circulating the lubricant in the clearance, temperature raise can be also controlled. Furthermore, to investigate a possibility ofa bearing that realizes rmch higher load carrying capacity, the effect of spiral groove depth to bearing characteristics is experimentally examined, resulting that the optirrum depth is about lOOμm.

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A rolling element has a spring characteristic in the transient displacement region from the stationary state to a continuous rolling motion. For this reason, a bearing having a rolling element is useful to construct an ultra-precision positioning device. In this paper, a mechanism for the damping capacity generation of the rolling element is investigated, to improve the dynamic characteristic of this positioning device. A stage supported by two rollers is constructed, and its tangential displacement is measured accurately when the driving force is acting. As a result, it is confirmed that the rolling element has a nonlinear spring characteristic. An energy loss is generated by the reciprocating motion of the stage in the transient displacement region. This is the main cause of the damping capacity. Furthermore, this energy loss or the damping capacity of the stage can be improved by using two rollers having different diameters

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In this paper, we researched the NRRO of an angular contact ball bearing for machine tools. At first, we developed a new apparatus for measuring rotational accuracy of rolling bearings. It was cleared that the total NRRO of angular contact ball bearing for machine tools became large in proportion to rotational speed.

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This paper studies effect of ultra fine surface structures on friction coefficient. Ultra fine structure was fabricated on a soda glass plate by nano-forming method with-a knife edge diamond tool. Friction coefficient of the fabricated surface was measured by a friction tester both under dry condition or wet condition with kerosene. Results show that ultra fine structure increases friction coefficient under, dry condition, but reduces factional coefficient under wet condition. Indentation load and indentation pitch also change friction coefficient.

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This paper proposes a theoretical model of the ductile-brittle transition in machining of hard-brittle materials based on.the fracture mechanics, and discusses the enhancement of the critical area by the externally applied hydrostatic pressure. The theory suggests that the critical area is proportional to K_<IC>^2/σ_O^2 , and that variation of the critical area by externalhydrostatic pressure depends on K_<IC>^2/σ_O^3. Machining test under external hydrostatic pressure was conducted on four kinds of hard-brittle materials. Results are compared with the theory, and effects of material properties on the critical area is discussed.

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This study aims to fabricate three dimensional microstructures on single crystal silicon by tribo-nanolithography (TNL) and wet chemical etching. The processed area of single crystal silicon by diamond tip withstands etching in KOH solution, and consequently protruding microstructure can be fabricated. TEM and SIMS analyses are utilized to study the mechanism of masking effect. As a result, it can be known that crystal silicon structures are converted to amorphous silicon by TNL process, resulting in affectting to the etch mask against KOH solution. Furthermore, comparison of etch rate between amorphous and single crystal silicon is conducted.

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Micro-meso mechanical manufacturing (M4) technology has recently attracted attentions as an alternative micromachining solution because of its potentials of processing variety in materials into 3 dimensional forms. Using a micro lathe, which is installable and operational in a SEM (scanning electron microscope), we control the position of XY stage of the micro lathe with visual feedback from CCD camera. We also compare the positioning control with visual feedback to the positioning control with number of pulse.

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This study aims to clarify the effect of ultra high-acceleration and vibration cutting on the reduction of plastic deformation and the improvement of machined surface. This paper reports on the result obtained through the molecular dynamics simulations on the ultra high-acceleration and vibration cutting of aluminum. From the simulation results, it was verified that applying ultra high acceleration and vibration to the cutting tool in cutting process reduces the plastic deformation. The effects of vibration amplitude and frequency on the reduction of plastic flow and cutting force in cutting process were also evaluated.

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The demand of high-speed turning for a superheat resistant alloy has recently been increasing in a field of aviation / space industry. Therefore, this paper proposes a new approach of high-speed turning for inconel718 by use of a multi-tasking machine tool that fused with a lathe and a machining center. As a result of machining test by the new machining method, it was realized that new method is 2.4 times of the conventional method in machining efficiency.

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An NC machine tool which is instructed machining operations by NC programs is widely employed in manufacturing systems. However, it is impossible .to change cutting parameters during machining operations, because cutting parameters are determined and coded as NC programs before the machining operation. This is the biggest problem to realize autonomous machining operations. The digital copy milling system which generates tool paths in real time is developed in our laboratory to realize autonomous machining operations. An NC machine tool associated with the digital copy milling system can perform autonomous machining operations unconstrained by NC programs. In this study, additional functions to detect and avoid tool collision are developed .for the digital copy milling system to achieve five-axis milling control. The experimental verification to show real time tool path generation for five-axis milling was performed successfully.

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This study deals with evaluation method of interference between cutting tool and workpiece in 5-axis control machining. In conventional studies, the 2-dimentional C-Space was proposed in order to generate cutter location considering the interferencebavoidance. In order to accelerate generation of the cutter location, a new calculation method of the 2-dimentional C-Space isbrequired. So, we propose a new idea of discrete 2-dimentional C-Space and high-speed calculation method. The proposedbcalculation method is based on new functions of graphic acceleration hardware (GPU). In the proposed method, geometricbcalculation of the discrete 2-dimentional C-Space is regarded as the drawing process of 3-dimentional computer graphics. As abresult, the high-speed evaluation of tool interference is realized by GPU functions.

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This paper proposes a measuring method of geometric accuracy of 5-axis machining centers by means of one ball and one displacement sensor instead of the ball bar system. The device of the method of using the ball as a measurement reference is more low-cost than that of the ball bar and can be applied to the small machine. To confirm the effectiveness of this measuring method, it was applied to the measurement of a real machine. As a result, the same measurementresults as the ball bar were obtained for the angular deviation. However, there is a problem to be solved for a positional deviation.

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The velocity of each axis is greatly changed when 5-axis machining centers are used to machine complex shapes. It is, therefore, the synchronous accuracy of rotary axes and translational axes is an important factor, when generating high accurate shapes. In this study, a dynamic model of the each axis including a rotary axis (C-axis) is developed, and synchronous motions of rotary axis and translational axes are simulated. In order to compare with the simulation results, experimental works were also carried out The synchronous accuracy of C and XY axes was measured using a ball bar system. In addition, a grid encoder system was .applied to detect the position of the translational axes.

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In this study, the model of a parallel mechanism type machine tool which was developed by Toyoda. Machine Works was made by using software for analyzing the complex mechanism, DADS. Although there are forty-eight joints in the PKM machine, the influence of the deviation on a circular movement was simulated considering only one deviation. The goal of this study is to determine the permissible geometric deviations existing in the joints of the PKM machine.

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Recently, high precision machining and high-speed cutting are required in the die and mold machining. To solve this problem, die and mold machining by 3+2 axis control machining, which is a method of indexing by 2-axis rotary motion and machining by 3-axis feed motion, on 5-axis machining center is proposed in this paper. In this machining process, the list of indexing angle should be determined automatically, because the shape of the die and mold is very complex to determine the angle by an machining operator. Therefore, the main objective of this research is automatic determination method of the list of indexing angle for the die and mold machining. Firstly, we propose the calculation method of optimum indexing angle candidates for required machining surfaces using normal vectors of the surfaces and cutting edge. Secondary, we propose the machinable area evaluation method of calculated indexing angle based on inverse offset method with state flag. Finally, we show the examples to demonstrate the effectiveness of the proposed methods.

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Development of the lathe industry's turret with motor for CNC lathe milling. By simplifying the structure of rotary tool drive and installing a motor for rotary tools in the turret, transmission efficiency was improved and thermal displacement by coolant was achieved. Moreover, the turret developed was ultra-rigid to take into consideration its role as tool holder. As a consequence, machining characteristics, precision, speed, and surface quality have been improved to a standard superior to those attainable by a small machining center.

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The "Driven at the Center of Gravity" technology was developed to improve the motion dynamics of machine tools. The application of the DCG theory enabled machine tools to achieve substantial improvements in design fundamentals such as machining time, accuracy, surface quality, and tool life. This theory is not only limited to machining centers, but can also be applied to all machine tools that have tools and workpieces which make relative movements. Machine tools using this DCG theory are able to follow orders precisely without any unnecessary movement.

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For improving the machinability of Al alloys, especially the chip breaking, low melting metals such as Pb and Bi have been added. Recently,. however, from the viewpoint of the environmental protection, the use of the low melting metals is restricted, and as the alternative method, dispersion of Si particles as the nucleus of chip braking is pointed out. Investigated the effect of Si dispersion on machinability of Al-Cu alloys, there was little influence of Si dispersion to machinability at dry cutting. However it was clarified that the chip breaking of Al-Cu alloys dispersed Si particles was improved remarkably by using cutting fluids.

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Cause of difficultly to machine austenitic stainless steel was studied by turning with new tool or wore tool. In cutting of SUS304 with wore tool, Vichers hardness at surface reached 600 against approximately 300 at inside. We thought it was because strain induced martensitic transformation generated at surface of SUS304.

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Investigated the effect of Si dispersion on machinability of Al-Cu alloys, it was clarified that there was little influence of Si dispersion to machinability at dry cutting, however the chip breaking of Al-Cu alloys was improved remarkably by using cutting fluids. In this research, turning test for various wrought products (A 1050, A2017, A5056, A6061, A7075)was carried out to investigate whether the tendency which appeared in Al-Cu-Si alloys would be also appeared in aluminum alloys on the market, and it was clarified the cause of chip breaking of aluminum alloys.

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In grinding of C/C composite, it is difficult to obtain a fine finished surface due to the anisotropic properties of C/C composite. The purpose of this study is to clarify the good grinding conditions and the grinding mechanism of SiC-C/C composite. This material was ground with a surface grinding machine in dry method. The surface roughness and the grinding forces were measured. The main results obtained are as follows. The grinding force in the wheel speed of 30 m/s was smaller than that of 24 m/s. The grinding force with SD230 wheel was smaller than that of SDC400 wheel. The surface roughness in SDC400 wheel was better than that of SD230 wheel.

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The machinabilities of intermetallics FeAl having various aluminum contents formed by reaction sintering were investigated by turning. Hardness of FeAl increase with increasing aluminum content. Tool wear in machining FeAl was mainly flank wear. Tool life decreased with increasing aluminum contents and this tendency was remarkable at higher than cutting velocity 1.0m/s. Machined surfaces of FeAl were smooth and clear cutting mark was found on surface at cutting velocity 0.5m/s. However, at higher than cutting velocity 1.0m/s, cutting mark was unclear and clack was found on surface of hard material having higher aluminum content. It was suggested that critical cutting velocity of FeAl using cemented Carbide P20 is about 0.5m/s.

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Stampable sheets are molded in compression molding method. The compression molding method has the problem that the glass fiber that stays on surface of molded part effects bad appearance. The transfer molding method is used as molding method of the other plastic materials. In this molding method, the blanks of Stampable sheets flow through the sprue. Therefore, the surface quality and the strength of molded parts differ from compression molding method. In this study, for the purpose of the improvement of the surface quality and the strength of molded parts, the transfer molding method was performed and the effect of molding conditions was investigated experimentally in comparison to compression molding method.

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In this paper, we propose the viscosity measurement method using laser trapping. We can measure the viscosity of films without contact using this method. Particles of the order of 2 micron in diameter have been trapped using a dry objective lens with large working distance. The principle of the viscosity measurement method is as follows. We investigate the maximum velocity which can capture a particle when optical radiation pressure is equal to viscous resistance. Then, we ask for the viscosity by applying Stokes's law using the velocity. And, it was proved this measuring method using laser trapping by viscosity measurement with glycerin is possible.

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Many studies on laser forming of thin plates have been done; however, few studies based on the buckling-mechanism have been made. Although characteristics of laser forming due to buckling mechanism have not been made clear, they are important for practical use because the forming of thin foils or plates is caused due to the buckling. In the present study, the bending of thin plates is made using 2 beams or line beam! bending direction is controlled.

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Laser machining is one of the most promising technologies for micro-fabrication as it benefits from its high power density, micron sized spot and non-contact accessibility. In most conventional Laser machining process however, the material is removed above its melting temperature by transforming the Laser power into heat energy. On the other hand, the material is also possible to be removed by a behavior called "ablation" if the incoming Laser power is big enough. Unlike the heating process, "ablation" directly breaks off the chemical bonding of the materials without introducing heat effect. Recent research have founded "ablation" is achievable by multi-photon absorption with Laser which produces pulse duration as short as pico(10^<-12>) and femto(10^<-15>) second. The aim of this study is to explore the potential of applying ultra short pulsed Laser into micro-fabrication. In this research, an ultra short pulsed laser micromachining system has been developed and its performance in three-dimensional micro-machining has been studied.

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Influence of wavelength and the kind of assist gas on machining characteristics of aluminum nitride using Q-switched Nd:YAG harmonics were experimentally investigated. Removal rate increases with the reduction of wavelength. Drilled depth increases proportionally with the number of laser shot at the beginning region of machining, while it stagnates after the proportional region. Drilled depth was greatly different by the kind of assist gas in the case of fundamental wavelength, while it was not influenced sensitively by the kind of assist gas in the case of harmonics because of its high photon energy. Debris was deposited remarkably except for fundamental wavelength, when blind hole is drilled using helium as the assist gas.

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Polymer materials are applied in broad field due to the high functionality, but polymers are easily affected by heat or forces in processing. Laser processing is used in many fields. Laser ablation is focused in this study, because it prevents to get form damage by the heat and PC(Polycarbonates) was used as sample piece. In this paper, machining characteristics of PC are experimentally investigated, while ablation process is analyzed considering both photochemical and thermal effects. The optimal process conditions for PC are discussed by comparing calculated results with experimental ones. The possibility of 3-dimensional form generation of laser ablation for polymer was investigated.

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This paper describes two-dimensional axisymmetric analysis of non-steady heat conduction of two-layers composed of resin and metal in laser drilling of printed circuit board. In the present analysis, resinous evaporation and diffraction of optical system for image formation were considered, and influence of diffraction on hole shape was investigated. Latent heat of evaporation and absorptivity were estimated using hole depth in experimental results. Laser intensity distribution at resin surface was estimated using the calculated result of diffraction in the experiment. Experimental hole shapes were in good agreement with analytical results considering diffraction. It was concluded that twodimensional .axisymmetric analysis considering diffraction of optical system for image formation is necessary to estimate hole shape in laser drilling of printed circuit boards.

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Cu direct drilling using CO2 laser is remarkable for a processing method which connects between layers of the multi-layered PWBs. In this research the index of absorption on the surface of copper foil for the outside layer circuit was obtained from the measurement data of the infrared rays thermography, and the relationship was examined between the copper foil surface absorption rate and the processing hole diameter. Moreover, the processing hole quality paid attention to the amount of the overhang.

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We draw attention to improving the laser-drilled hole quality. In the present paper, we applied a data-mining method to the FEM data of thermal stress in order to elucidate the factors which influenced the thermal stress of the copper plating on the laser-drilled hole wall. As a result, it is clear that a new factor which influences the unreliability for circuit connections is mined out, despite the presence of complex factors. Moreover, we tried express the above results visually using the face method.

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This research aimed to develop the super-low pressure controller which was able to give the work piece the stable super-low pressure to obtain the machined surface quality equal with the separation abrasive processing. Super-finishing process can make good finished surfaces in short time. In addition, super-finishing is widely used in the last finishing of slide planes of precision parts such as bearings. We processed super-finishing with this device to confirm the ability. As a result, the machined surface was improved when pressure decreased. Moreover, when stone pressure was 0.2MPa, the roughness of finished surface was 12.5nm, which the working accuracy was the highest.

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