In Japan, ultra-precision macining technology has grown with an expanded demand of high precision parts that are used for private industries such as OA instruments, optical fiber communication and semi-conductor manufacturing devices, And, the development process is different from in U. S. A Passing 20 years, the technology is now indispensable as supporter of these industries. The technology with the key word of "ultra-precision" is able to produce high value added and display originality over in future. This paper introduces ultra-precision machines and the components technology used.

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This paper describes the temperature of lubricating oil and torque loss of spindle in hydrostatic journal bearing. The temperature of oil rises due to the viscous friction. To reduce the temperature rise and torque loss, we propose the U shaped multi -recess type and evaluate the performance by numerical analysis. This solution shows that the oil temperature and torque loss are remarkable influenced by turbulent flow.

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This paper describes the static characteristics of hybrid (water/air lubricated) hydrostatic journal bearings. Aerostatic bearings have often been used for high-speed spindles because of its low friction and high accuracy of motion. However aerostatic bearings have disadvantages such as lower load capacity and bearing stiffness compared with water-lubricated hydrostatic bearings. On the other hand, water-lubricated hydrostatic bearings have higher damping coefficient and larger load capacity though larger power consumption is needed at speeds. In this paper, therefore, we propose a hybrid journal bearing which can be used as both an air-lubricated and a water lubricated hydrostatic bearing. The proposed bearing can achieve both low power consumption and large load capacity by selecting air or water as the operating fluid according to the operating condition of a spindle. In addition, the static characteristics of the proposed bearing are theoretically clarified and the usefulness of the bearing is shown.

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Recently, new technology has been utilized to develop environment-friendly angular contact ball bearings for machine tool spindles. Bearings with a bore diameter of 100mm have been tested to confirm the operating characteristics of these newly designed parts. In addition, a specially designed lubricant nozzle was also introduced and found to reduce the noise caused by balls cutting off the air jet of air oil by 6 to 8dBA at speeds greater than 10,000rpm. The newly designed nozzle in combination with the newly designed bearings is also effective at reducing the air-oil consumption. The newly developed bearings are capable of operating with an air rate of 10NL/min and an oil rate of 0.03mL/21min at a speed of 21000rpm. This is only 40% of the air rate and 10% of the oil rate of a conventional system. The electrical energy consumption of this newly developed environment-friendly technology is expected to be 20% less than a conventional system.

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To prevent backlash for accurate motion control, ball screw has various types of the way to apply preload, and the friction torque characteristics on each types are different. The friction torque on double nut preloaded ball screw dynamically varies after motion direction change. The friction torque after motion direction change is lower than that in the steady state. It's quite different from backlash because the preload is not absorbed and rotational motion is perfectly converted into Linear motion. This paper clarifies the difference of friction torque characteristics between double nut preloaded ball screw and over-size ball preloaded ball screw.

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This paper describes some new technologies on Linear Motion guide for machine tools. This Linear Motion guide should be satisfied with the requirements of performances and ecological behavior requested by machine tools engineer and end-user. As for performances, static stiffness, running accuracy and good economy are major concerns for machine tools engineer. As for ecological behavior, there exist some aspects. These are "Low emission from machine to environment", "Resistability against solvents provided inside the machine" and "Human friendly characteristics".

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The present paper presents a method to improve motion accuracy of a precision feed device driven with open loop control by means of 'Walking Drive', which has been developed by the present authors. Displacements of the contact block and voltages applied to the piezoelectric actuators are measured at the same time, and it is clarified that the motion error is caused mainly by the nonlinearity between the displacements and the voltages. Thus, the repeated learning control is applied to compensate the voltages, and a feed motion error of 300 nm under the open loop control is reduced to 58 nm by the compensation.

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The purpose of this study is to realize a magnetic bearing of nanometer rotational accuracy at a high speed. Unbalance force which arises from non-coincidence of the center of rotation and the center of inertia in a spindle decreases the rotational accuracy. The spindle motion control around the center of inertia is desirable for decreasing the unbalance force. In this paper, first, a method for estimating the center of inertia from currents of electromagnets is proposed. Then the spindle is experimentally controlled to rotate around the estimated center of inertia. Experimental results show that the rotational accuracy of the spindle is 13.3nm (3σ) at 2000 min_<-1>, and the electromagnetic control force which synchronizes with the spindle rotation is suppressed to 0.19N which is 6.7% of that around the center of profile.

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At present, it is afraid of a limit of photolithography in the semiconductor field again to the requirement of which becomes rapidly minute electron beam lithography technology attention. As for the field as well, downsizing is the flow of the necessity as well as this except for the micro-machine which advanced micro-machining technology should lithography be necessary, the optical communication and so on we development research and development electron beam device use. So, the outline of the development device, an application example, and so on are shown about the study on the various adaptation fields that we advance it at present that report.

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This paper describes a new polishing method in which electrolysis is combined with free-abrasive polishing to form mirror-like surfaces of stainless steel, aluminum, titanium and tungsten with roughness less than 1 nm Ra and flatness less than 1 μm. Removal rate in cases of stainless steel and tungsten increases with current density in wide ranges where mirror-like surfaces are formed. Eelectrolysis in cases of aluminum and titanium doesn't increase removal rates but it only contributes to forming mirror-like surfaces in narrow ranges of current density by means of controlling chemical activity of these metals.

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Micro dimple texture should be evaluated from the viewpoints of the following : a shape, a surface quality, a configuration, a performance as an optical surface, and so forth. In this paper, the shape and the surface quality are measured by the techniques of the interferometory and the geometrical optics, respectively. The interference fringes indicating the error from the designed shape were obtained by Twyman-Green interferometer. And the patterns of the tool mark on the surfaces of the dimple were visualized by the ray tracing method. The pattern agreed well with the pattern obtained by theory.

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Clearance at the interface of two solids in contact should be evaluated for sealing gas leakage. In this study, first of all, we designed experimental apparatus. It enabled us to detect the gas leakage in the sensitivity of 1.0 × 10^<-8> (Pa・ m^3/s) which is equivalent to the clearance of 10〜50nm. Next, the relations of gas leakage with the experimental parameters such as surface roughness of the interface, contact pressure, vacuum pressure, etc. were measured for the purpose that micro-space at the interface should be investigated. Namely, we tried to estimate the micro-space quantitatively based on the relation between the clearance at the interface of two solids metals in contact and their surface roughness. As a result, it becomes clear that qualitatively theoretical characteristics correspond comparatively well with experimental ones. However, the analytical values don't agree quantitatively with the experimental ones, approximately doubled. It would be caused by the reason that rising up of the valley part of the surface roughness appears due to deformation of top asperities in contact.

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IN this study, critical condition for ring cracking of turbine-grade Si_3N_4 ceramic was examined through the Sm_2Co_<17> particle impact (dynamic loading) test and the quasi-static indentation (static loading) test. Moreover, some indentation tests using split specimen (or BIT) were carried out. Regarding the stress for the ring cracking, hydrodynamic pressure assumption (pcv) gave plausible value to that by the quasi-static indentation test within the present combination of materials. Indentation in the split specimen brought Hertzian cracks. In the continuous specimen, however, no cracks appeared at the same load.

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Although cavitation impacts normally cause damage in hydraulic machinery, the impacts can strengthen metallic materials as same as shot peening (SP). In case of peening by cavitation impacts, the shots are not required, thus the peening is called "cavitation shotless peening (CSP)". In older to figure out the mechanism of the improvement of life time of forging die treated by CSP, residual stress and hardness were measured with and without CSP. Tested materials were tool alloy steel SKD61. It was revealed that the residual stress of the surface treated by CSP was more compressive than that of not peened specimen and still kept compressive after heat treatment.

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The distributed virtual factory (DVF) based on the concept of distributed simulation has been proposed as a new simulation environment to evaluate the performance of large scale manufacturing systems. To develop a DVF, it is necessary to integrate existing area-level simulators modeled by various simulation softwares via computer networks. In this paper, DVF is constructed by implementing a communication interface, developed by C++, VisualBasic etc., on existing area-level simulators, where each programming language is supported by the corresponding simulation software to enhance its functions. The function of communication interface and the implementation procedure are described through an illustrative development of a hypothetical DVF.

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The objective of the present research is to develop an integrated process planning and scheduling system which is applicable to the holonic manufacturing systems. A systematic method is proposed, to select suitable machining sequences and sequences of machining equipment, taking into consideration of production schedules.

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In order to realize an autonomous milling, the tool paths and cutting conditions have to be decided in real time manner using the predicted and measured information of machining process. In this paper, the algorithm of in-process tool path generation is proposed to modify the cutting conditions according to the machining status and machining troubles. To be more precise, the machining area is divided into some cells and the tool path is generated as the removal sequence of machining cells. The modification of the tool path is also realized by dividing into the smaller cells and so on. As the case study, the in-process tool path generation and modification is made by deciding the cutting conditions in parallel with predicting the machining status using the cutting simulator that was already developed.

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This paper describes the prediction of cutting force by Genetic Programming (GP) method in ball-nosed end milling. In recent years, the prediction methods of cutting force in flat end milling have been proposed. However, it is difficult to predict cutting force in ball-nosed end mill, because the shape of cutting edge is more complicated than Flat end mill, and it is need to take tool attitude into consideration. In this study, modeling of cutting force by GP in ball-nosed end milling is tried on the basis of in-process measurement data.

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This paper deals with the development of CAD/CAM system for getting a good machined surface. In case of inclination machining using the ball end mill tools, various change of the tool attitude can be carried out. Thus inclination machining is used in order to avoid machining in a tool tip. We searched a difference of surface appearance and surface roughness in terms of the tool attitude. However it is difficult to keep a tool attitude when a tool interference is considered in case of the form for which 5-axis control machining is needed. This research aims at development of the CAD/CAM system in order to create the tool path for good machined surface.The tool path is created in consideration with the machined surface quality of different tool attitudes. Using deviced method, cutting start point, tool feed direction and tool attitude can be determined automatically.

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This paper deals with the automatic deburring of castings. The deburring works that are performed in the final process of production area are still done by skilled workers since the automation of deburring works is difficult. The study aims at developing the automatic deburring system by making use of CAD data of workpiece and industrial robot. The tool selection system selects a tool suitable for specific burr of castings among a variety of tools. The CAM system decides how to deburr with the selected tool with regard to the tool imformation file which indicates the shape and condition and the tool path data is automatically generated.

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This study deals with the development of new hammering tool called "air-chipper". Hammering tool is one of typical deburring tools, and air-chipper is conventionally used to perform the deburring work for cast workpices. Although air-chipper is an effective tool, there are problems of durability and quality since it is driven by compressed air. Excess energy after hammering motion transfers to damper rubber and causes the deterioration of rubber, which leads to the breakage of a chisel holder of air-chipper due to the crash with the stopper. In addition, the difficulty to directiy measure the chisel motion causes uncertainty of deburring quality. Thus, the improvement of air-chipper was intended to solve the above problems by introducing an air damper to the air-chipper. It is possible to diagnose the deburring quality by measuring the inner pressure of air damper room. As a result, air-chipper installed in a deburring robot system reveals an effective performance in combination with the image processing device.

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Cutting fluid has been used for the cutting processing. However, the use of the cutting fluid contains the factor of the environmental problem. Therefore, the cutting fluid-less processing has been required. For one of the cutting fluid-less processing, the cold-air jet processing has been advocated. In the cold-air jet processing, it becomes important that the processing point is supplied, while temperature and pressure of the cold-air jet were kept. In this study, in order to efficiently supply the processing point with the cold-air jet, the endmill tool with air holes was produced experimentally, and the processing experiment was carried out. The following has been clarified : Effect of the air hole diameter of the tool on processing characteristics and effect of the tool hole direction on processing characteristics. From the experimental results, it is proven that there is no problem to 1.5mm at air hole diameter. And, it has became about 2.8 times the tool life than the dry-type processing in case of the endmill with the air holes which could supply the processing point whole area with cold-air jet.

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Dead -end deep stepped holes of special alloy (A6063) for centralized lubrication distributer are machined with a new cutting fluid supply system, which can effectively generate oil filmed water drops. Better surface finish and smaller dimension error can be obtained comparing with a conventional emulsion cutting fluid. Most suitable results are achieved when the oil filmed water drops are supplied through tool center oil holes.

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As a low environmental burden processing, the cold-air jet processing has been advocated. Generally, the much cutting fluid is used for the turning. The cutting fluid carries out lubrication, cooling, and chip cleaning of the processing point. In the cold-air jet processing, the lubrication of the processing point supplies the vegetable oil mist of the necessary minimal dose, and cooling and chip cleaning are carried out in the high-speed compression cooling air. In this paper, the lubricity of the cold-air jet processing has been clarified.

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A new type of metalworking fluid is developed that conforms to recent environmental requirements. Comparatively large water particles are covered with oil film and sprayed on a machining point with a soft air jet. The performance of this metalworking fluid is studied in an aluminum alloy milling process with changing the oils. Surface tension of the oils and cutting forces are measured and multiple regression analyses are performed for the measured results. Experimental results show that interfacial tension of 100 nm film thickness oils on water and oiliness of the oils effect on the machining performance.

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The purpose of this paper is to investigate the potential application of the cutting in the nitrogen atmosphere. In order to clarify the effects of the nitrogen atmosphere, cutting tests were carried out on plain carbon steel S45C with carbide tool. Cutting tests were conducted in the sealed chamber of which the atmosphere was changeable. Nitrogen, argon, carbon dioxide gases and air were used as the atmosphere.

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As a low environmental burden turning, cold-air jet processing which does not use the much fluid like the convention is devised, and it has be made that the characteristics are clarified to be a purpose. In this study, coolability problem of the processing point in the Cold-air jet processing is noticed, and to begin with, the effect of cooling effect on the turning characteristics by the supply condition of air flow has been clarified. As this result, cold-air jet supply condition has been found, of which the coolability is high by low flow and low-noise level, cold-air jet supply condition.

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Since it is correspondent to environmental problems such as global warming, discharge of the emission, consumption of the energy, use of chemical substance, the cutting fluid-less processing has been exposed to the attention. As substitution processing of the cutting fluid, there is the cold-air jet processing. In the cold-air jet processing, it is important to efficiently supply the processing point with the low-temperature compressed air. In this study, vacuum insulated pipe with high thermal insulation performance has been installed in machine tool. The insulative property of vacuum insulated pipe has been clarified. It has been confirmed that there is almost no temperature loss, when it installs the vacuum insulated pipe in the spindle of machining center, and when it supplies the cold-air jet, and that it can supply the processing point with the cold-air jet. And, it has been confirmed that the machine tool dose not receive temperature effects by cold-air jet.

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The use of the cutting fluid contains the factor of the environmental problem. For one of the cutting fluidless processing, the cold-air jet processing has been advocated. In the cold-air jet processing, it becomes important that the processing point is supplied, while temperature and pressure of the cold-air jet were kept. In this study, in order to efficiently supply the processing point with the cold-air jet, the endmill tool with air holes was produced experimentally, and the processing experiment was carried out. From the experimental results, it is proven that is no problem to 1.5mm at air hole diameter. And, it has became about 2.8 times the tool life than the dry-type processing in case of the endmill with the air holes which could supply the processing point whole area with cold-air jet.

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Machining trend for total cost reduction in current manufacturing industry and proposal of lightweight and high-precision dual face contact system and high-precision col let system for the purpose of lowering production cost.

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BT standard tooling is a tooling interface that is held with a 7/24 taper. A gap exists between the spindle nose and the tool flange when the tooling is clamped. However, when users demands high speed and high precision machining capabilities, and when the cutting tools for high speed is being developing, the serious problems become clear on 7/24 taper standard tooling. We introduce 1/10 short taper, taper & flange double face contact tooling "NIKKEN NC5 Tooling System" for the high speed and high precision machining.

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This papers describes the examination of stiffness, thermal deformation, and cutting performance of a newly developed high-speed spindle holder of machining center. Experimental results show that thermal deformation of the developed high-speed spindle holder was same as a conventional spindle, but that stiffness was low. It is considered that the precision machining of mold models is done by use of the developed spindle on the conventional machine if the overhang of tool is small.

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Authors proposed already a direct tool chucking mechanism for high-speed spindle, which incorporates a mechanism to prevent the chucking force reduction at high-speed. In this paper, the new version of the chucking mechanism was proposed to resolve its weak points and analyzed the basic characteristics of the mechanism with finite element method. As the result, the following were made clear : 1) The accuracy of tool position after chucking is very high, and 2) Chucking force is distributed widely from the back end of tool to front end of chucking mechanism.

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In a die machining, the unbalance of a spindle system consisting of a spindle and a tool holder decreases the machining accuracy and the holding function of the machine tool. A new method has proposed to adjust the unbalance of the spindle system and an unbalance adjustment system has been developed which able to easily adjust the unbalance of the spindle system of a high speed machining center. The outline of the system has been given. The performance test results show that the new system is effective certainly to decrease the unbalance of the spindle system.

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This paper explains the tooling management & control with the latest digital tooling system. The RF-ID system and OPEN-CNC technology are used specifically for the transmitting of the information between the digital tooling and the machining centers.

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This paper describes the theory, structure and performance of ECOSAVER which is a device to make micro-fog and ECOTOOL SYSTEM used for semidry cutting. And it also shows the examples of some cutting tests.

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This paper discribes the result of micro structure fablication in spherical single-crystal silicon by anisotropic etching. Etching experiment with spherical single-crystal silicon covered with mask pattern has shown that side surface angle and depth of groove were changed every 90°.

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In order to obtain ideal flatness and surface roughness of glass substrate disk, a new finishing method with micro-patterned hard asperities was fundamentally studied. An anisotropic etching process has possibility to produce the surface covered by silicon abrasive asperities of extremely well defined shape and size. Different height and apex angle of asperities were produced by the changing of etching time before and after removal of SiO_2 coating during etching process. The height and apex angle of asperities were uniform on the surface. The height of asperities was controlled in sub-micron meter order. The apex angle of asperities was controlled from 40 to 164 degree. Glass convex specimens were scratched with these asperities in different shape. The depth of the groove for glass specimen decreased with apex angle of asperities. These results show the possibility of this new finishing method for glass substrate.

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The research that micro-machining of the square on the surface (100) of single crystal silicon by the machining cantilever installed in friction force microscope is presented in this paper. It was found that the machined area is changed into striking convex after the work piece is etched by KOH solution. The relation that the height of the convex depends on the machining conditions especially on the density of KOH solution is understood. Moreover, the efficiency of ultrasonic cleaning with etching to improving the roughness and removing of the remained is confirmed. And the method of maskless formation of micro-structure as the application of the experimental results is proposed.

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This project aims to develop a micromanipulation system, which enables unskilled operators to implement in-situ operations to a tiny object at an environment of Scanning Electron Microscope (SEM). The current research has developed an image-processing algorithm to real time capture the movements of the tool tip, to translate the movements to the hypothetical magnification and then to adaptively control the movements of manipulator accordingly. This paper has described the visual feedback algorithm and force feedback device to enhance the operation ability of the system.

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Development of milli-machine for super finishing is discussed in this paper. The micro tool which is formed by anisotropic etching of silicon wafer is attached to the milli-machine. The milli-machine is driven by the repulsion of magnetic force. It is found that the developed milli-machine has the cutting ability of the Al-Mg alloy material.

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