An NC machine tool is widely employed in manufacturing systems. However, it is impossible to change cutting parameters, such as depth of cut and stepover, to maintain the stable cutting and to avoid the cutting trouble during machining operations, because cutting parameters are determined and coded as NC programs before the machining operation. The digital copy milling system which generates tool paths in real time is developed to solve the problem mentioned above. An NC machine tool associated with the digital copy milling system can perform autonomous and intelligent machining operations unconstrained by NC programs.

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An evaluation method for synchronous motion of translational and rotational axes in 5-axis machining centers is proposed. In the proposed method, the X and the C' axes are simultaneously controlled and a circular path is generated under a constant peripheral feed speed. The relationship between the diameter of the circular path and the distance between both centers of the rotary axis and the circular path is useful for evaluating the accuracy. If the diameter of the circular path is smaller than the distance between both centers of the rotary axis and the circular path, the influence of the backlash becomes strongly. If the offset between machine coordinate origin and the center of the C' axis is large, it is difficult to evaluate the inaccurate synchronization appropriately.

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Dynamic synchronous accuracy is an important factor in multi-axis machine tools because the velocity of each axis is greatly changed in the machining of complex shapes such as impellers. This paper proposes a controller design method for feed drive systems to improve the multi-axis synchronous accuracy. In the design method, the velocity loop in the control systems is designed by using "the Partial Model Matching Method", and the positional loop is also designed by using the frequency characteristics of the velocity control loops designed. In addition, a feed forward controller which can compensate the servo delay is proposed. The parameters of the proposed controllers can be determined systematically without trial and error. The effectiveness of the proposed method in the multi-axis synchronous motion including rotary axes was evaluated by the simulations of multi-axis machining. As a result, it is clarified that the proposed method can greatly improve the synchronous accuracy.

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The linear motor driving mechanism is adopted for positioning mechanism of the machine tools to realize high speed and precise positioning, because of frictionless and no backlash. When the table of machine tools is driven at high speed, two or more linear motors are used for the same axis to obtain the high thrust power. In case of using more linear motors, however, the position of the table changes because the thrust force of each linear motor does not become the same. In addition, this causes to generate micro vibration and to change the velocity of each linear motor due to yawing around the center of gravity. In this study, the imaginary motor control method was proposed with three linear motors for driving table to control the position of the gravity, the vibration and yawing. From the results of simulation and the experiments, it is confirmed that the proposed method can control the position of the gravity, the vibration and yawing independently.

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The present trend of multi functional machine tools leads to the complicated thermal deformation and vibration characteristics, causing the energy to increase for improving them. The research and development of the machine tool consuming minute electric power is desired in view of global environmental conservation. The optimum design of rib structure of the machine tool is one of the effective methods to improve its characteristics without unnecessary energy consumption. With respect of the thermal deformation, static deformation and natural frequency of the column of machine tools with rib structure, this paper examined the optimum shape of a simplified rib structure column model by applying the multi-objective generic algorithm to FEM analytical results. The optimum design variable values for the thermal deformation were conflict with the values for the natural frequency of the 1st order mode of vibration ; nevertheless, the design variable values were obtained improving the thermal deformation, static deformation and natural frequency in comparison with those at the initial values.

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Since laser interferometer systems are high accuracy and non-contact measurement, the systems have been incorporated into such manufacturing equipment as precision cutting machines, measuring machines and lithographic systems. The measurement error in interferometers is due primarily to the change in laser wavelength that is affected by the refractive index of the air, which depends on its temperature, humidity and pressure. Without proper environmental compensation, degradation in system accuracy and repeatability will occur and limit the quality of final products. We have developed a new environmental chamber and a new wavelength tracking compensator for precision machine tools with laser interferometer system. The measurement of tool-workpiece relative displacement and the raster flycutting test are performed to verify that the two products are effective in minimizing the laser measurement error and making progress in the form accuracy. The experimental results, which imply the highly corrected accuracy of less than 100nm, show a remarkable improvement compared with the case without compensation.

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[in Japanese]

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This paper presents a development of a large-size FMS (Flexible Machining System). Production equipment such as machine tools is always required high productivity. One of the methods to realize it is FMS. We have developed a large-scaled FMS that consists of the latest 12-multiple face machining with 5 axes, based on FMS technical know-how so far. The max. table size is '3m×6m', and the portable weight of LOADER ROBOT is 30t. Although it is a large machine, a table-change system is adopted so as to carry out setups outside. We have accomplished the target speed and accuracy by operating the developed systems, and found out the FMS is capable of 720-hour automatic operation from the current data we have been collecting.

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For the manufacture products with helical gear, we had proposed a new extrusion process by using the divided die. In this method, the setting of the die is as follows: The die is divided into the direction of the circumference of the product. Afterwards, each divided dies were fixed with the gap by shifting the dies in the extrusion direction. In this paper, the fundamental characteristics of this extrusion process are investigated by carrying out extrusion test that variously changing the gap of die, velocity of stem and number of gear. The change in the velocity of stem doesn't influence the twist of gear so much. There is a limit in the value though the twist of gear increases, as the space between dies increases. The twist of gear increases with increasing the gap of the die. However, there is a limit of gap to produce the products.

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This study aims to clarify the interaction between Si wafer and individual diamond abrasives in grinding processes in an atomic level. This paper reports on the results obtained through the nano-scratching simulations by using the molecular dynamics method and the experiments by an atomic force microscope (AFM), respectively. In the experiments, the influence of environment, such as atmospheric pressure and temperature, were evaluated. From the experimental results, the formation of embossment on the scratched area was observed under air, while the formation of concave groove was observed under vacuum. It was also proven that the scratch groove under high temperature becomes deeper than that under room temperature in both the experiments and the simulations.

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Thick films are needed in micro-electro-mechanical systems as insulation, piezoelectric and ferroelectric materials. To form the thick film, Powder Jet Deposition (PJD) method is proposed. In the PJD process, particles are sprayed on the substrate under the condition of ordinary temperature and atmospheric pressure. In this study, a new double nozzle type PJD device is developed. In this report, relationship between PJD conditions and vickers hardness of formed film is investigated. And it is found that gas pressure have large affect on strength of ceramics film compared with jet angle and distance.

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Ultrasonic Machining (USM) is known as an effective method for machining brittle materials. The materials are removed by impacts of the abrasive grains which are pressurized by ultrasonic vibrating tools. The purpose of this research is to make micro grooves on the brittle materials accurately and efficiently by ultrasonic machining. Using the electrorheological fluid assisted USM, we could make an accurate micro groove on brittle materials. In this paper, the decrease of the average diameter of abrasive grains according to the progress of the machining is investigated, in order to take a first step to make micro grooves efficiently. The results show that the average diameter of abrasive grains decreases according to the amount of the removed materials.

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This paper proposes a new fabrication process of a nano/micro composite metal structure by using nano plastic forming method. This process consists of three steps ; first fabricate a nano/micro mold by nano plastic forming on a plate, then coat the plate with a metal by using spatter coating, and finally polish the metal plate to remove unnecessary coating. The process is examined by using soda glass and aluminum alloy as a plate. Some results are shown in this paper.

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In this study, the grinding of SCM 415 steel hardened by carburization and quenching treatments was carried out under supply of coolant included chips or abrasive grains. The correlations between surface quality and contents of chips and abrasive grains were investigated with respect to the number of scratch, surface roughness and grinding forces. The number of scratches gradually increased up to ca. 100/10^2cm^2 against contents of contaminations. In addition, it is noticed that abrasive grains have significant effects on formation of scratches rather than the chips in grinding fluid.

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Surface plunge grinding of glass quartz is conducted with a SD270 metal-bonded diamond wheel, the cutting edges of which are truncated so as to be aligned with the height of the grinding wheel working surface, and the ground surface roughness is investigated in terms of the truncation depth and the workpiece speed. It is found that the ground surface roughness decreases with the increase of truncation depth and converges to a value depending on the workpiece speed. The ground surface roughness decreases with the workpiece speed, and the roughness of Ra 16nm was obtained at the truncation depth of 15μm and the workpiece speed of 0.6m/min. Furthermore, resin-bonded diamond grinding wheels of various mesh sizes are applied to the grinding of the glass quartz under the same grinding conditions, and it is found that the cutting-edge-truncated SD270 metal-bonded grinding wheel brings about the roughness better than that obtained from a SD3000 resin-bonded grinding wheel.

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Recently, higher processing accuracy is demanded for the automobile parts from the rise of the requirements of environment protection and energy conservation for the cars. In this report, all the existing methods for the processing of the introduced gear cannot satisfy the desired accuracy and the desired cost demanded by the gear surface and the characteristic of the product any more. Therefore it is necessary to develop a new grinding technology that should have the same high accuracy as the gauges. Accordingly, we developed a highly accurate but cheap mass production grinding method for the processing of the gear surface. It utilizes the theory of pressure transcription and realized by a hold and rotate mechanism. All of the development objectives have been accomplished and the new processing technology is detailedly introduced in this report.

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An automatic wheel-approach system for a surface grinding machine using a hydrophone which the authors had developed is enhanced. The previous system was not reliable enough for an actual use because the coolant-flow in the nozzle is not stable and S/N ratio of the detected signal was not big enough. Then, a fluid-flow regulator and new fluid-supply nozzles are developed to enhance the S/N ratio and effects of the devices on the system reliability are experimentally investigated. An automatic approach of a porous-wheel from 5mm-clearance between the wheel and a workpiece, Δy, has been successfully performed. The wheel can be positioned as accurate as Δy=15-40μm in 4-8sec.

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In this research, the high temperature Fine Particle Bombardment (FPB) treatment system was developed. This system is a combination of FPB treatment and high frequency induction-heating. The specimen was produced in temperature ranging from room temperature to 900℃. From element analysis, using SEM and EDX, series of processing temperature higher than 600℃ a layer containing Cr element of shot particle was observed. In addition, by structural analysis using XRD, it was revealed that this layer is FeCr_2O_4. Then, the corrosion resistance was evaluated for each series using electrochemical measurement in 3%NaCl solution. From these results, corrosion resistance improved as the treating temperature rose, and Cr-900 series, samples treated at 900℃, showed a good corrosion resistance.

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The phrase 'standardization' is indicative of competitiveness in the Japanese manufacturing industry. In manufacturing plants, a wide variety of cutting tools is in use today. In many cases, the cutting tools are stored in disarray. The cutting tool management is far from well-ordered. This paper describes a logical procedure of standardizing the cutting tool specification. The eternal objectives of manufacturing industry are lead time reduction and cost reduction. The accessible as well as effective way of achieving them is the optimization of the manufacturing process. The manufacturing process optimization in metal cutting consists of three basic elements ; cutting tool standardization, CAM utilization, and cutting condition optimization. The standardization of cutting tool specifications is the foundation for improving productivity. Therefore, the cutting tool standardization is inextricably linked with lead time reduction and cost reduction, and should be considered business challenge.

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Recently, it is difficult to expect a stabilized production and its span because of globalization of manufacturing, consumer's various inclination, and short-lived products. Responding these needs, the production system based on the operator's flexibility, for example, cell production system, has been reexamined. But the ability of the essential function system depends on the personnel management and the working division. Nowadays, examination using production line simulation system has increased, although, it is important to reconsider the proposal based production content, procedure, and working division. Nevertheless, the changes on current simulation model and examinations of new system require an enormous time. It is becoming a heavy burden. To improve this system, the new modeling methods and U/I are contrived.

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This study proposed a method for suppressing the torques and consumed kinetic energy to drive manipulators with consideration of the effect of inertial forces. The present study deals with the case that manipulators are controlled by specifying only the starting and ending points. The trajectory between both points can be determined arbitrary. The total motion of manipulator is determined by giving the initial position, initial posture and the motion curve of each input joint. The motion curve reveals time profiles of angle displacements, velocities and accelerations of each actuator. In this study the motion curve is expressed by polynomials and their coefficients are decided by two heuristic algorithms. One is representative method ; GA, and the other is SHA proposed by S. Lin, et al. The study determines the optimal motion of PUMA560 by the proposed method, and reveals it effectiveness.

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Necessity of small and accurate aspheric lens is increasing in medical service and optical communication. To measure such lens, micro-stylus whose tip ball is less than several of micrometers in diameter is necessary. This paper describes the development of a micro stylus with tip balls of 10μm and 50μm in diameter, respectively. The tip balls are silica spheres which feature of high accuracy and affordable price. The silica sphere is glued to the end of the stylus made of stainless steel, which serves as the probe of an air-bearing displacement sensor. Surface profile measurement of an aspheric lens is carried out by the micro-probe.

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This paper describes an instrument called nanoshape for measuring surface forms of aspheric optical elements on the processing machine. The effectiveness of the on-machine measurement system is confirmed by the result of compensation processing based on the measurement data. The instrument employs a contact-type scanning stylus. An original inclined self-weight method is designed to control the contact force. In this method, the contact force is generated by inclining the air slider of the instrument, on which the stylus is attached, from the horizontal plane only a little below the stylus. As a result, an extremely steady low contact force (measuring force) can be easily achieved. This method has a peculiar error that occurs by inclining. This error tends to increase as the angle of inclining grows. The evaluated radius variation can be reduced enough by setting the measuring force to tens of milligrams.

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For measuring the surface profile of soft thin films such as photoresists we proposed the method using multiple ball cantilevers and constructed a multi-ball-cantilever AFM system, which covers a wide area at high speed. Each cantilever has a ball stylus with a diameter that dose not plastically deform measured surfaces. In this research, to realize high accuracy in measurement, we observed the behavior of the multi-ball-cantilever using the white light interferometer. We discussed the nano measurement characteristics of the multi-ball-cantilever by measuring the step height standard.

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As probing technique for Nano-CMM to measure microparts at the accuracy of nano order, the study on laser trapping probe has been progressed. In this report, we proposed circular motion probe and experimentally investigated the property of probe to enable coordinate measuring in all over oscillating plane. As the result, we proved that we can detect position of workpiece at the resolution of 30nm by monitoring oscillating amplitude. In addition, we were able to detect proximity angle between probe sphere and detected plane by monitoring change of orbit of circular motion. It is suggested that nano-position sensing in lateral 2D plane is possible with these properties of circular motion probe.

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According to advanced functionality in a wide variety of equipments in these days, ultra precision, high complexity and high efficiency of fine-fabrication is required. Not only performance of machine tool but also downsizing of high accurate working tool itself has been an important issue to realize above conditions. In this study, on-machine tool measurement technology using laser diffraction which is able to manage micro tool and able to post in the machine tool has been establishing. In this article, the on-machine tool measurement device is developed. The developed on-machine device is carried out a response measurement experiment of hundreds nano-displacement using piezo stage then the fundamental characteristics of the developed measurement device is verified.

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The novel finishing process using the optically trapped particle as a polishing tool have developed in order to improve the surface quality as well as a few nano meter RMS. This process enables to polish the surface in selected area as small as 10μm^2. The mechanical contact of the particle makes the roughness of the substrate smooth. It is considered that a machining process is enhanced by the thermal, chemical and photo induced effect. In this report, we perform the laser trapping of a silica particle with a diameter of 1 micro meter by using ultraviolet laser in order to investigate the photo induced effect in UV wavelength.

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Dry drilling of composite/metallic stacks for aircraft components is extremely difficult to keep sufficient hole quality and efficiency of drilling process. Problems of the dry drilling of the stacks are in chip ejection, chip formation and high temperature especially for titanium alloy. To clear these problems, low-frequency vibration (10-50Hz) drilling is applied in this study. Controlled vibration was applied in drill axis direction. In this paper, to clarify the mechanisms of drilling temperature and tool wear reduction in low-frequency vibration drilling, drilling temperature was measured by using tool-work-thermocouple method. As the result, drilling temperature at cutting term in the vibration drilling was same as that in the conventional non-step drilling even though the average uncut chip thickness was largely different.

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Machinability of Ti-47.7at%Al intermetallic compound having TiAl-Ti_3Al full lamellar structure is investigated by orthogonal cutting test using cemented carbide tool K10. Defects such as cracks, peelings due to brittle fracture along with the direction of lamellar were observed on the machined surface. The larger brittle cracks were occurred in cutting by tool with the rake angle of +5°. For machining in the rake angle of -5°, the depth of crack occurrence was independent on the direction of lamellar. On the other hand, for machining in the rake angle of +5°, it increased rapidly at the lower angle between lamellar direction and cutting direction than 90°.

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This paper deals with the step generated at the grain boundary in an ultra-precision diamond cutting of phosphor bronze for a typical metal mold of Fresnel lens. In this study, the cutting experiments were carried out with an ultra-precision cutting machine by a single crystal diamond tool in order to investigate the relationship between the generation of grain boundary step and the cutting conditions. The influence of the thrust force component and the heat treatment on the step at grain boundary is discussed. It was found that the thrust component of the cutting force and the feed rate condition greatly influence the magnitude of the step at grain boundary.

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In this paper, machining performance of driven rotary tool which is expected to apply high efficient cutting for difficult-to-cut materials was investigated and also suitable cutting condition of it was examined. The rotary tool is attached to a milling axis on a multi tasking lathe, the parameters related to the rotary cutting (cutting speed V_w, circumferential velocity ratio V^*, tool inclination angle β, normal rake angle α_n) were independently adjusted. Furthermore, understanding of mechanism of the rotary cutting was deepened by applying of oblique cutting and simulation based on shear angle theory. In the results, it was found that the application of driven rotary cutting into high speed cutting is possible. Temperature of the tool rake face while cutting increase with increase of tool inclination angle. However small tool inclination angle made chip flow angle changed to be negative and chip adhere to machined surface.

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In this report, Al-Si alloys which contain 2-25mass%Si was processed and machined by dry cutting in order to clarify effect of eutectic Si particles and primary Si particles on machinability of Al-Si alloy. The number of chips per unit weight was rapidly increased in machining specimens containing more than 15mass%Si. Moreover, Chip thickness and curl radius decrease with increasing the eutectic Si. It was found that these are due to higher hardness of matrix caused by eutectic Si particles. Therefore, it is considered that the crack of primary Si which act as a nucleus of chip breaking grow up, and thereby the increase of number of chips was promoted.

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Machinability of Al-Mg-Si alloy is investigated using an orthogonal cutting test. The yield stress and elongation rose by increasing Mg_2Si content. This tendency was prominent in the aging condition of T6 (Aging at 180℃ after solution heat treatment). On the other hand, the yield stress and elongation increased largely by addition of excess Si in the whole aging condition. The cutting resistance of a material added excess Si (C5) was smallest, and the burr formation at the edge of work was suppressed. In the aging condition of T6, the cutting resistance was large because of large strength of work and thickness of chip. The width of burr decreased by prestraining of 10 percent before machining.

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In order to investigate the influence of second-phase particles on chip breakability of aluminum alloys, turning test for various wrought aluminum alloys were carried out with carbide inserts (K10) in dry and wet cutting conditions. In the materials, Al_2Cu, Al_6Mn, Mg_2Si, Al-Fe-Si system compound and eutectic Si were observed as second-phase particles. Chip breakability of materials which containing Al_2Cu or Si as second-phase particles were superior than that of materials with Mg_2Si or Al-Fe-Si system compound. This tendency was more prominent in wet cutting than in dry cutting. The Al_2Cu and Si particles on the machined surface were fractured by cutting tool in machining. It was estimated that those fractured second-phase particles acted as nucleus of chip breaking during machining. Moreover, the increase of the chip breakability in wet cutting was attributable to the promotion of fracture of Al_2Cu and Si particles due to the Rehbinder effect.

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The mechanism that one table is put on another, it is called "a serial mechanism", is generally adopted for a XY-table of a high-speed machine tool. However, the XY-table causes some problems ; big oscillation occurred by heavy moving parts of machine and high gravity position. To solve this matter, we developed a new table system "The Differential Slider". The Slider has great characteristic features that we can lighten and slim machine due to no source of power and linear encoder in X direction. On the other hand, the table with no moving part is easy to come under the influence of disturbance. In this paper, we focused on The Differential Slider control by the disturbance observer. According to our experiments, we confirmed the effect of disturbance observer and the availability of the Differential Slider mechanism.

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The positioning table systems applied for recent precision equipments require nanometer-positioning functions, high speed drive capability and a compact structure. In order to meet these requirements, a non-contact mechanism by non-contact guiding and driving are effective. In this paper, therefore, an ultrasonic levitation table system driven by linear motor was developed. The table system was able to decrease vibration transmission from ultrasonic guideway to the table by a multiple constrained structure. The results of actual table positioning experiments confirmed that the developed system has remarkable performance.

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In order to realize an ultra-precision machine tool, it is necessary and indispensable to develop ultra-precision table positioning technology. In particular, the high speed and ultra-precision table system with wide driving function is urgently required. A belt-driven table system is effective means for coarse driving mechanism because of compactness, simple structure, quick response and long driving distance. In this paper, a positioning table system equipped with a belt drive mechanism was newly developed and then the basic performance of the developed table system was evaluated.

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High precision, low production-cost, and environment-friendly table systems are required from machine tool builders. A linear-motor-driven table with hydrostatic water bearings is newly developed and its performance is investigated. The table supported by constant-flow water bearings is preloaded by magnetic force of the linear motor. A magnet plate of the linear motor is mounted on an inclined base of the table system so as to preload the table in horizontal and vertical directions. Static stiffness of the table system is affected by bearing clearance and water-flow volume. Load carrying capacity and static stiffness of the developed table under 6μm bearing clearance were estimated at 17.6kN and 1.95kN/μm respectively.

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A new magnetostriction material that is called Giant Magnetostriction Material (GMM) has attracted attentions as new actuator and senseor in various fields. Because they can output large displacement and high power that is compared with those of conventional magnetostriction materials. In this reserch, their potential as oscillator is paid attention, and the speaker that is consisted of low height actuator with GMM is developed. In this paper, in order to establish the system that best shape of oscillator is determined, as a first step, the characteristics of the GMM and the oscillator are investigeted.

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One of big problems in MQL cutting process is disposal of chips accumulating on working table and work piece in machine tools. In order to solve this problem, a new machining system that immediately collects chips from a cutting tool is suggested. The tool was developed and a cutting test was carried out. To suction the chips stably, the chips are necessary to be broken into small pieces. In this study, effects of a chip control plate equipped with tool are investigated in turning process. It was found that length of chip is shortened by the chip control plate.

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In MQL intermittent cutting of aluminum alloy, it is considered that an interface between tool and chip is directly lubricated with supplied oil under boundary lubrication regime because of relatively low contacting pressure and low temperature rise. In order to investigate effect of roughness on boundary lubrication performance of lubricant oil, frictional experiment and intermittent cutting test were carried out under severe contact condition. From the experimental results, it is found that frictional coefficient became small if using ester type lubricant and tool with rougher surface under boundary lubrication regime. It is suggested that this reduction in friction by ester with rougher tool is brought from oil retention by roughness valley.

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Improvement of lubricity between tool and chip or workpiece is essential for obtaining good cutting performances. In particular, the achievement of high lubricity is required in MQL cutting. MQL cuttings, however, have problems relating to low lubricity or low stability and, as a result, the introduction to practical cutting industry is limited. Then, to overcome the above problem, cutting tools with micro structured surface, that is, micro grooves were developed in the hopes that the grooves play the role as retainer of cutting fluid. A series of MQL cutting experiments revealed that the cutting shear angle became larger and the cutting force became lower, as compared with the conventional cutting tool without micro grooves. This demonstrated that the micro grooves brought low friction to cutting tool surface.

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The great deal of cutting oil consumed during the machining processes is one of the environmental issues. The Minimum Quantity of Lubricant Supply (MQL) method, called near-dry cutting, have attracted a lot of attention recently. However, in MQL method, oil mist is discharged to the environment with compressed air, and it float around in the factory. In this research, Direct Oil Shot Lubrication Method (DOS) is proposed and applied to milling processes in order to reduce the float of oil mist. The amount of oil mist in DOS is considerably suppressed, compared to MQL. And DOS is compared to DRY and MQL cutting for being evaluated lubrication effect. In cutting force, flank build up, and surface roughness, each value of DOS is close to that of MQL.

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This paper deals with form accuracy and tool paths in machining with small ball-end mill of which diameter is approximately 2mm. Machining with contour tool path may have form accuracy worse due to acceleration, deceleration and servo response of machine motion. Tool path expected to improve this form accuracy, is proposed. Machining experiment using those tool paths is conducted to compare the form accuracy at edge part of object workpieces. The result shows that the proposed tool path improves the form accuracy.

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This research effort is focused on analyzing machining error in arbitrary direction in ball end milling of cylindrical surface theoretically. Ball end milling is widely used to machine dies, molds and various aerospace components that are characterized by 3-dimentional free form surface. They are always required to be of high accuracy. In this study, the machining errors at various parts of machined surface are evaluated. And the theoretical results are verified by the experiments. The workpiece material is 0.45%C plain carbon steel. And the cutting tool used in this research is HSS. The theoretical results agree well with the experimental values.

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Ball end mills are widely used in machining of parts with sculptured surfaces. The properties required for ball end milling are high productivity, high machining accuracy and integrity of machined surface. In this study the machining error theory is applied to the analysis of spherical surfaces. The workpiece shape is concave and convex. The work material used is plain carbon steel. Cutting tool is a cobalt enriched high-speed steel (Co-HSS) ball end mill. The machining errors are examined for various cutting conditions and cutting modes. The machining error in down cut is lager than that in up cut. It is seen that the influence of cross-feed on machining error is largest in the cutting mode of down cross-feed and down cut. The machining error in concave workpiece is lager than that in convex workpiece. But in down cross-feed., the machinging errors in both shapes are almost same.

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This paper deal with cutting mechanism and cutting performance of machining for inclined surface by a ball end mill. The cutting edge shape of the ball end mill is very complex, so we use 3D-CAD for calculation of chip area during machining. Then cutting performance is discussed using the evaluate value calculated by the multiplication of the chip area and the length from Z axis to the gravity of the chip area. And also the influence of the spindle inclination in the feed direction on the cutting performance is considered.

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Two kinds of austenitic stainless steels, SUS 304 and SUS 316, were milled using TiAIN coated cemented carbide end mill developed for milling difficult-to-cut materials. Tool wear reliability analysis was carried out based on the tool wear progress. Reliability functions ; hazard rate, tool failure probability density and reliability, were derived from the wear data. The features of reliability functions coincide with the cutting characteristics of materials used in this study. Austenitic stainless steel SUS 304 shows a poor machinability compared with SUS 316 and carbon steel S50C.

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This study deals with geometric analysis of workpiece removal in multi axis control machining with ball end mill. In order to predict both surface roughness and accuracy of workpiece shape in finish machining process, it is required to apply a new estimation method which can cope with quite small feed rate in cutting conditions. So, in this study, we introduce the developed removal model of workpiece, which is designed to consider influences of cutting edge roundness. And, we analyze both removal depth on each cutter mark and cutting error on workpiece shape, for a case of ball end mill with a throwaway chip. From results, we can find that distribution of removal depth on cutter mark is strongly influenced by tool posture and shape error caused by tool deflection is often bigger than height of cusps.

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