The purpose of this study to accomplish three-dimensional trapping of micro objects by a YAG laser with the Liquid Crystal Spatial Light Modulator (LCSLM). This paper describes a prototype experimental system. The experimental result shows that performance of phase modulation decreases with the increases of temperature of LCSLM. For this reason, the cooling system is necessary for LCSLM. The experimental result using cooling system shows a constant performance of phase modulation for a LCSLM. Using the cooled LCSLM, we have carried out the two-dimensional trapping of a particle. Using YAG laser a global trapping system has been developed by cooled LCSLM.

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This paper deals with the micro-welding of the glass substrate by YAG laser. The micro-welding technology is required for the precision assembly of the micro components in the optical transmission devices, LCD plate and so on. In the conventional joint way of the glass materials, bond material, which was melted by heat energy, joints the joint materials. In our proposed method, two glass plate was overlapped in which the absorbent was painted at the joint area of glass inside, and the YAG laser was absorbed in only the painted area Therefore, only the joint area will be welded and glass surface will be clear. In this experiment, slide glasses were tested to be jointed by the YAG laser and a feasibility study of new welding method was carried out.

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This research examines the machining characteristics of a new micro-machining process featuring ultrasonic cavitation in distilled water. In the process, the cavitation based on the ultrasonic vibration varies with the geometry of the tool and the clearance between the target surface of the workpiece and the tool connected to the horn. The effects of the tool geometry and clearance must change the erosive action of cavitation and thereby the material removal. The machining experiments demonstrated that the smaller the clearance and the deeper the tapered angle of the tool tip, the deeper was the machined depth because of the higher machining force due to the enhanced cavitation. In those cases, the machined geometry closely followed the tool's geometry. At clearances larger than a certain value, regardless of the tool geometry, the cavitation generates a dent in the area corresponding to the center of the tool.

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Non-silicon based micro machining requires multiple principles to access different materials according to each objective, and also a single set-up to attain the repeatability. Using conventional machine tools normally take more than one process from roughing to finishing thus is energy consuming, costly and yet inconsistent. Newly developed in this research is a multifunctional macro-machining system capable of milling, turning, grinding, buffing, polishing, EDM, ECM, Laser machining and their combination. The system has four degrees of freedom, desktop size and 0.1 μm positioning accuracy. This paper particularly investigates the electrode wear and its form accuracy sustainability as applying this system to manufacturing carbide mold for aspherical lens.

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When the cold roll formed products such as pipe, channel, angle, etc, are cut by press or saw, both cut-off edges open, and magnitude of the distortion differs. It is considered that the distortion occurs due to release of residual bending moment and residual twist moment. This report shows the residual moment that is measured by Sachs method, and also the calculation result of residual moment that is obtained by using of principle of minimum potential energy.

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A drilling burr profile measurement method has been presented in this paper. The measurement method is based on image processing techniques. A measurement system ; consisting of a measurement instrument and software ; has been developed. Using the system, four side images of measured burr profile are projected by four prism mirrors located around the burr. Consequently, images of top and four sides of the burr can be simultaneously taken by CCD camera located right above the burr. Burr thickness and height are calculated from taken image using developed software. The measurement accuracy by the system is examined using simple geometry objects. Measurement tests of drilling burr have been made and drilling burr thickness and burr height have been obtained.

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For indirect sensing of the crater wear of diamond cutting tool, features of the cutting force relating to the wear are investigated. The ultra-precision diamond turing experments show that the dynamic compornent of cutting force change from random to chaotic, when the crater wear develops. Since the change can be detected by calculating the time-lag until the autocorrelation function of the cutting force becomes to 0, this feature extraction is useful for the tool wear monitoring.

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This paper will propose a new approach to measure deformation, flank wear on micro diameter tool cutting edge. In other words, we can evaluate the change of cutter diameter. Furthermore, due to this approach bases on applied laser diffraction, it can be also applied to in-process measurement. Subsequently, this theoretical analysis and fundamental experiment will show that it is available to measure cutting edge deformation, flank wear in submicrometer resolution.

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A method for motion accuracy measurements of machining centers has been presented and then measurement system has been developed. The system consists of the mechanical instrument with a parallel mechanism and software to generate path of MC from measured data. A feature of the system is to be able to measure not only circular paths but also other paths such as square paths. The mathematical relationship between MC motion and measured data from the instrument are described. Setting angles of the instrument to tested MC have been estimated based on derived relationship. Calculation accuracy of developed software has been studies by simulations. Measurement tests using developed system have been made for both square and wave paths.

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This paper presents a new laser interferometric distance measuring method which can be applied to parallel mechanisms. This method has a strong merit that the gap of joint and the error by bending deformation in the value of measured length are includes in measuring value, so that the influence of these error can not be appear in the system evaluation and the calculation the coordinates. The key of this method is that the mirror of interferometer is sphere and a lens is located in front of sphere by the distance of the focus. The experimental result of the travel within 100mm is describes and compared with linear scale.

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Accuracy of conventional interferometric methods for three-dimensional surface profiling is limited by errors of intrinsic metrics inside interferometric microscopes. A simple technique of XY axes calibration is proposed to measure those intrinsic errors resulted from CCD pixel arrays and objective lens distortion. In this self-calibration technique, a inclined plane is used as the specimen. Two sets of profile measurement data before and after a small shift of the specimen in the X (Y) axis direction are used to obtain the calibration curve concerning the intrinsic errors. Test results based on computer simulation are reported.

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To make clear the wear property of Fe-Al intermetallic compounds, the five specimens of Fe_3Al, FeAl, FeAl_2, Fe_2Al_5 and FeAl_3 were subjected to abrasion tests using abrasive paper with some grain size. In FeAl_2, Fe_2Al_5 and FeAl_3 specimens with relatively high Al composition, the wear surface translated from ductile wear surface into brittle wear surface with chipping at the specific size of abrasive grain. The effect of applied force per abrasive grain on this ductile-brittle transition was discussed from the relationship between micro cracking condition in indentation test and grain size on abrasive paper.

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This paper proposes machining method under high hydrostatic pressure as a new damage-free machining method for hard brittle materials. For machining tests under-high hydrostatic pressure, a new machining device was developed. The device consists of a turntable and a tool stage inside a pressure vessel, and they are controlled by motors and a handle installed outside of the vessel. The device also consists of a load cells to measure cutting forces, and position sensors to detect tool position. Machinability of glass was examined by the device under 400MPa and 0MPa. Optical observation of the machined traces has revealed that hydrostatic pressure is efficient to minimize machining defect.

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This paper describes the system which we developed for cutting brittle materials with a small depth of cut to realize ductile mode cutting. This system has orthogonal 3-axis mechanism with a high-speed linear motor on the X-axis, a hybrid-type feed mechanism composed of coarse and fine positioners on the Y-axis, and a micrometer positioner using a ball screw on the Z-axis. We evaluated the performace of the system and realized ductile-mode shaping in case that shaping speed was 1mm/s.

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The mechanisms of abrasive grain machining processes are investigated based on thermo-elastic-plastic finite element simulations of orthogonal cutting with a negative rake. When machining of a steel of SK-5 with negative rake at low, intermediate, or fast cutting speed, bulge-type, ribbon-like, or serrated chips are formed, respectively. First, changes in the equivalent stress, temperature, plastic strain, and plastic strain rate observed at a spatially fixed point during a serrated chip formation are clarified. This indicates that a adiabatic shear occurred in the serrated chip formation. Next, changes in these cutting state parameters at some convective points of different types of chips are clarified. This shows the conditions of transition from a type of chip formation.

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The influence of material properties of the workpiece SK-5 on the orthogonal machining processes with negative large rake angle are investigated through the finite element analysis. The analysis shows that the material properties have a great influence on the machining processes, but that a critical uncut chip thickness, under which chip forms with great difficulty, changes complicatedly when material properties including the strain hardening exponent, yield stress, thermal conductivity, and initial temperature, are changed.

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This paper deals with an experimental study of ultra-precision diamond cutting of magnesium alloy (AZ31). In order to investigate the machinability such as the cutting force and the surface integrity and understand the problems in a micro cutting, the experiments on the diamond cutting of magnesium alloy and pure aluminum with an ultra-precision turning machine has been carried out. The machinability of magnesium alloy was compared with that of pure aluminum and discussed. Consequently, both the thrust force component and the surface roughness obtained by cutting of magnesium alloy became larger than that of pure aluminum. It was also found that the inclusions or the defects in the work material caused to generate the scratches on the finished surface and influenced the integrity of mirror surface.

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For objective of cost reduction of automobile unit parts, we develop to change process in the cutting process that Equipment Cost is low from the grinding process that Equipment Cost is high. In hardness materials not less than 60HRC, cutting is possible in continuity cutting by CBN tool and ceramic tool. However in interrupted cutting of spline outside diameter of unit parts, there is matter that tool life is short so that continuous impulse force acts on tool cutting edge. So we applied oblique cutting method in interrupted cutting, and investigated tool life. As a result it was able to extend tool life for conventional single point cutting largely, and was able to make roughness too small than conventional grinding level.

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The effect of porosity on tool life in cutting by cemented carbide tip (P20) was investigated using two kinds of sintering iron have different porosity at the various cutting depth. The result was that the cause of shortening tool life was rather porosity than hardness of specimen in a cutting condition. Besides tool life was shortened in cutting at the high cutting depth and the high cutting velocity condition. To sum up, tool life was shortened at the condition of high cutting speed and high cutting depth. These result were likely caused by heat shock in interrupted cutting.

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Analysis tool of milling process is developed to design tool geometry. Dynamic cutting process can be simulated with edge shape function defined as height of cutter. End milling process can be modeled as a pilling up of orthogonal cutting planes containing edge velocity and chip flow direction on divided cutting edges. The model can also consider the effect of slope on cutter trace made by the prior cutting edge. Two types of shear plane model can be realized according to the increasing rate of chip contact length. Chip flow direction can be determined to minimize cutting energy, which is the sum of shear energy on shear plane and friction energy on rake face. Ball end milling process with reduced chip contact length is analyzed to reduce tool vibration with cutting forces. It is shown that analysis software developed is effective for parametric design of cutter shape such in roughing end milling process.

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Heat generation in high-speed cutting causes various troubles. It makes a tool life short and accuracy of machined surface worse. In this study, tool temperature behavior in high-speed milling is simulated using finite element method. This report, it is analyzed that the transitional thermal behavior in short cutting time by loading intermittent heat flow is superimposed on the steady state of tool temperature. It is compared with experimental result with thermo infrared imaging camera, then heat flow ratio into tool and heat convection to air are determined.

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In the machining process, the work hardened surface layer and the cutting burr are generated by plastic deformation beneath the machined surface, which was due to the pressure of a cutting tool. Therefore, it is considered that there is some relationship between them. The relationship between the size of the cutting burr and the depth of the work hardened surface layer was investigated experimentally in the orthogonal cutting with a shaper. As a result, it was clear that there is a significant relationship between the size of the cutting burr and the depth of the work hardened surface layer and that they can be estimated by the shear strain applied to the chips.

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This paper deals with the development of a new centerless grinding method, the regulating-wheel-less centerless grinding. In convenient centerless grinding, a regulating wheel to support the workpiece and control its rotational speed must be employed. Consequently, not only a high-precision regulating wheel unit and a high-accuracy dressing technique for the regulating wheel are required, but also it is difficult to produce a small-size grinder for machining micro parts. To solve the above problems, a new centerless grinding method without regulating wheel unit has been proposed. In this method, an ultrasonic vibrating shoe, the end of which is in elliptic motion at a high frequency, is employed instead of the regulating wheel. In this work, an experimental apparatus based on this concept has been produced, and grinding tests have been carried out. This report describes the produced apparatus and test results.

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Exponential type lost motion is sometimes observed especially in large-size machine tools which use linear ball guide way or wiper seal. This paper theoretically analyzes the motion of the drive system which uses sliding guide way and is affected by the nonlinear spring characteristics of the wiper seal and calculates the radius error and motor torque during circular interpolation motion. Using test stand that has sliding guide way and simulated wiper seals, some motion tests are conducted. The measured radius error and motor torque indicate similar tendency with calculated results.

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We have always proposed and provided the best machine which can satisfy shorter due date and lower cost on machining for die and mold as a machine tool maker. We have also aimed higher speed and more accuracy. It is clear that the quality of machining data and the high-speed control which can realize it are very important. So, we accomplished high-speed control DCS IV which previous high-speed control DCS III was upgraded. In CNC of the latest machine, this high-speed control DCS IV is attached. But most of the companies can't easily buy a new machine during the long recession. So we have developed high-speed and high-quality feed function PUMA NET which can use new high-speed control even in existing machines and shorten machining time and improve the quality of machined surface with low initial cost.

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The basic construction is thermal symmetry and combination of simple cubic. It brings small and parallel thermal deviation. Additionally the "Thermal Active Stabilizer (TAS)" cancels them continuously smooth. This system can be offered with small extra cost.

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This paper describes a trial of the active thermal deformation compensation for a high-speed machining center. Deformation sensors and thermal actuators which consist of electrical heaters, fins and cooling fans were implemented to realize the active thermal deformation compensation. The position and the inclination of the spindle were predicted using a matrix method. The predicted error was less than 5μm in case that the spindle speed was varied up to 12,500rpm.

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A new method is proposed in the present research to monitor tool wear of endmills by comparing measured cutting force with calculated one. A new cutting force model is developed to correlate the milling force with the tool wear, and cutting experiments are carried out by utilizing a vertical machining center. Variables in the cutting force model are identified so that the calculated milling force is best fitted with the measured one. It is clarified by the experiments and the identifications that there is a good correlation between the tool wear and the identified variables. Unlike the conventional monitoring methods, the present method based on the cutting force model is expected to be able to monitor the tool wear without utilizing any databases.

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This paper presents a method of adaptive control of tapping in order to perform high speed, high productivity tapping by using newly developed intelligent machine tools. This method means changing acceleration rate and cutting speed of tapping by means of the value of cutting torque by monitoring cutting force with internal sensor. To use this method, the cutting torque increase is not so sharp at the hole bottom vicinities because of prevention of chip jamming. In order to inspect the productivity and safety of tapping, a new algorithm is proposed and a new NC system is fabricated. As a result, productivity improved 32 % experimentally as compared with conventional system.

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This paper describes a research on a prediction of contact between a grinding wheel and a workpiece. The phenomenon of whitening of a grinding fluid, accompanied by the wheel approach to a workpiece can be detected using a laser sensor. The laser stripe is illuminated on the trailing flow of a grinding fluid and the reflection energy is measured. The illuminating and sensing point for an appropriate measurement is experimentally investigated. Effects of the distance between a wheel and a workpiece, wheel speed, and fluid flow rate on the laser reflection intensity is investigated, and the possibility of the prediction of contact is discussed.

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The Japanese first five axis simultaneous controlled machining center was developed in 1970, that is after ten years of the first practical Jpapanese NC machine tool developments. The basic study has started at 1968, and was conducted by the committee of JSME. This paper describes the history of the development, its industrial effects,and actual example of the machining operation. It would say that this development change the Japanese machine tool design way.

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Recent demands for calibrating the machine tool accuracy become very tight, as the production user requirements on machining accuracy increase its levels. The accuracy inspection method is standardized in ISO standard. This paper describe the present status of its standardization tendency in the ISO TC39/SC2 which is the special committee on the machine tool accuracy.

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Analysis of machining errors is very important in design process of machine tools. A kinematic model is proposed in the research to represent the motion errors between the tools and the workpieces. Two types of machining centers are considered in the research to analyze the machining errors due to the kinematic errors of the feed motions. The effects of the kinematic errors on the machining errors of the products are analyzed and compared by applying the model developed here.

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This paper deals with the identification of alignment errors in five-axis machining centers. There are thirteen alignment errors in each five-axis maching center. Three alignment errors in the three translational slideways are identified by circular tests using a Telescoping Ball Bar. In this paper, assuming the use of a Telescoping Ball Bar, identification methods for the other ten alignment errors in five-axis machining centers are proposed. The theoretical background for identification is given by form shaping theory. The validity of the proposed identification method of alignment errors in the work-tilting type of five-axis machining center is confirmed by experiment.

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This paper describes a method of automatic compensation of spindle head position and workpiece mounting error for 5-axis control machining. One has been applied to machining for a mold die of the bumper for the cars by the new 5-axis machining center which machine sculptured surfaces efficiently. The other has been applied to machining for a marine propeller by the general-purpose machining center.

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In order to reduce the setup time, 5-axis controlled machining centers are recently used for the production of general machine parts. Therefore, 5-axis controlled machining centers with higher working accuracy have been required. However, the evaluation method of kinematic performance of such 5-axis machining centers has not been investigated. In this study, a ball-bar technique is applied to the measurement of the 3-axis simultaneous control motion, and the factors that affect to the kinematic performance are discussed. The measured results show that the wear of the worm gear affects to the rotational accuracy of the rotary axis. It is found that the worm gear causes the fluctuation in the rotational speed of the rotary axis.

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Friction (hydrodynamic) guideways have been used as a feed drive system of traditional NC machine tools, such as machining centers. It is known that the machine that has this type of guideways is good for heavy cutting. On the other hand, it has more friction, and so the driving system has larger lost motion, in consequence, positioning accuracy can be worse without linear encoder feedback. Recent friction gudeway design has been dealing with the friction decrease. This paper describes the comparison of motion accuracy (mainly the amount of lost motion) of the machines built in these ten years by using circular test measurement.

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The process for making worm gears introduced here is the process performed by our GALAXY form rolling machine. Electric Power Steering has good reputation never the less it has a high cost. The worm gear it requires is processed, currently by milling and grinding. We expect our research to contribute to economical production by cutting costs. Form rolling costs about 40% less than the cost of cutting. Our new genuine computer control GALAXY -the only one fully utilizing computer capacities- succeeds in economical and precise form rolling of hi-tech worm gears.

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The thermal deformation of a grinding spindle has direct effects upon the quality of machined parts. The final solution is the use of zero-thermal-expansion glass-ceramics as a spindle material to reduce the thermal effects, though there are three problems such as the material cost, machining cost and risk of spindle failure. The ultra-precision surface grinder having a glass-ceramic spindle of zero-thermal-expansion has been built in 1985 and had gotten world-class special results for many years. The spindle has been damaged during operation and a damaged part has been observed. All cracks are originated from ground holes in the glass-ceramic spindle. From the results of bending tests on variously finished zero-thermal-expansion glass-ceramic samples, it is clarified that final finishing process after etching produces higher resistance for the breakage of a glass-ceramic spindle.

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In the oil-air lubrication applied to the high-speed spindle supported with a set of ball bearings, very severe noise is emitted so that the high-pressure air supplied through a couple of thin nozzles may collide with steel balls which are rolling at high speed. In this paper, the sound noise radiated from the spindle unit has been measured, changing theflange shape of the tool holders, the supplied air pressure, the number of nozzles and so on. A special spindle supported by magnetic bearings is also used in the experiment. From those experimental results, it is confirmed that the collision air causes such sound noise.

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In putting ultra-high-speed-milling to practical application, CAD/CAM, machining-center, cutting-tools, and molding-tools need to be prepared. For this, it is essential to determine the true nature of high-speed-milling and its requirements to determine the true nature off high-speed-milling conditions, introduce the required CAB/CAM, machining-center, cutting-tools, holding-tools and latest trends of tool-management-techniques, as well as propose specific solutions for existing problems. It will especially focus on introducing high-speed-milling in the molding and parts manufacturing industries, and discuss indetail the selection of cutting-tools and holding-tools, importance of tool-managiment, and ideas on the construction of cutting conditions databases.

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This paper describes examples of ultra high speed machining by aero-static bearing spindle, so called the air spindle. Air spindle has no metal contact, therefore there is no limitation to turn it for long hours in constant at maximum speed. In addition run out of the spindle (NRRO) is smaller than 0. 07μm and then tool life can be extended. Due to the above-mentioned feature, air spindle realizes an actual ultra high speed machining only by using small size cutters.

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Hereunder is the explanation for cutting example of Ultra High Speed Machining Center model SPARKCUT which has raid feedrate of 100 m/min with simultaneous opposite 2 axis movement, and super high speed spindle 75,000min-1.

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In recent years, the worldwide development in information industries has been grown tremendously and the market is becoming full of information devices ; such as Personal Computer, cellular phone, and other devices, even in a regular household. Those information devices have a very short product lifecycle by aggressive technology innovations and seeking for more comfortable product designs, and hence, the demand for its dies and molds and injection molding machines has been booming. The company develops and manufactures the linear motor equipped electrical discharge machines and machining centers to satisfy the need of making precision molds in a short time. This reports deals with the linear motor equipped machining centers. "MC180L" (Fig1)

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This paper describes Servo Technology for 'High Speed and High Precision Machining'. From the market, feed axis of machine tool is required to realize high speed feed, maintaining high accuracy. In order to meet this request, FANUC has introduced the concept 'NANO CMC', which enables ultra high speed and high precision. This NANO CNC system consists of Nano meter unit Interpolation by CNC and Nano meter level Control by newly designed servo system, called αi series. Nano control is constructed by organic combination of servo motor with ultra smooth rotation, encoder with super high resolution, amplifier with high precision current detector and control software with high response and high precision.

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Binderless cBN compacts were synthesized by the direct conversion method from hexagonal BN under high pressure and high temperature without additives or catalyst, and cutting performances of them have been investigated. The fine-grained (<1μm) and high purity (>99.9%) compact has high hardness and high-temperature strength. In addition, this compact has high thermal conductivity above 300W/m. K. The cutting tool of the binderless cBN compact shows good wear resistance in the high speed milling of cast iron or steel, because of the excellent thermal properties of the compact. The cutting edge is cooled down rapidly during the non-cutting time of milling due to the high thermal conductivity of the compact. As the result, this cBN compacts are applicable to cutting tools of high speed milling for gray cast iron at over 25m/s in both dry and wet condition and for steel at 16.7m/s in dry condition.

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In this paper, the flank wear and the surface roughness of machined surface are investigated by high speed milling of hardened steel for a small size ball end mill using a high speed spindle attachment. And also it is investigated that the influence of a tool life on the inclination angle of workpiece and the minimum quality lubrication (MQL) method. By the results, it is shown that the long tool life and the small surface roughness are obtained by the conditions of step up milling and the MQL method.

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In recent years, high speed milling has been widely noticed in the light of machining efficiency. However, tool wear and breakage are becoming conspicuous with high speed milling. It is essential to develop new tools suitable for high speed milling. This study deals with the design and fabrication of ball end mills with special tool shapes on 3D-CAD/CAM system, which is developed by ourselves for high speed milling.

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Recently, high-speed milling technique for realizing high efficiency and high accuracy in the manufacturing of die and mold has become useful and important technology. In this technology, a small diameter ball end mill is used at the cutting conditions such as small depth of cut, high rotational speed and high feed speed. And, it becomes important to optimize the specifications of the tool for high-speed milling. This paper describes the effects of edge treatment for ball end mills using micro blasting method. The conditions of edge treatment using micro blasting and the cutting characteristics of high-speed milling were investigated.

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