This paper describes the new 5-axis vertical machining center "D500". Conventional 5-axis machines have two major difficulties. One is that it is not easy to realize both high accuracy and high speed at the same time. And another is that it is not easy to make the fullest use of the 5-axis machines. In order to solve these, "D500" is equipped with a unique machine structure and three DD motors in the two rotating axes.

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This paper describes about high performance machining center for hard machining application. In general, hard chatter vibration will occur in cutting process of titanium alloy. To avoid the chatter vibration, dynamic stiffness and damping ratio are very important factor. Sufficient supply of high volume coolant is effective solution to increase of tool life in cutting process of titanium alloy.

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This paper describes composite machining of internal grinding and Hard-turing. Internal grinding of small bore is one of difficult process. Because low rigid quill causes bending by grinding force and makes taper bore. And this force is influenced by condition of grinding wheel and unstable. This bending prevents high tact fine grinding of small bore. In order to keep good accuracy and high grinding efficiency, we reduced stock removal for grinding. Hardening of material makes deformation and required thick stock removals. We added hard turning on internal grinder so that minimize stock removal for grinding. This combined process achieved 30% reduction of total cutting time.

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This paper presents the technologies for high precision machining with high-speed and high-acceleration driving of feed-axis of double-column machining center. In the proposed approach, linear motors whose stator has no magnet are adopted to the feed-axis. In addition, the force pulsation of linear motor is reduced by arranging of magnets and canceling effects of two sliders. Moreover, we proposed to adopt the feed forward compensation of the mechanical deflection which caused by high-acceleration.

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In order to improve operation rate and productivity of machines, not only machine performance but also ease of operation and convenient maintenance are important. I will introduce what design for ease of operation and convenient maintenance is, with reference to actually developed machines. Specifically, I will introduce the following: Design for front-located tool magazine for ease of tool setup and visual check, other centralized devices which daily check is needed for, and even manual storage location and foot switch storage.

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Recently, needs to high accuracy and high-value added products are becoming more sophisticated. From this, there are many strong demands to machining system such as high productivity, high accuracy, capability of quick change in production line, and energy conservation. Shaft-shaped parts, which are one of mass production products, tend to have several processes such as turning, heat treatment and grinding. Commonly, process integration of these processes has been thought to be difficult. We have developed multitasking machine which can integrate turning, heat treatment, and grinding process, and have developed elemental technology to realize this, to increase productivity of mass production parts, as a subsidized project of NEDO. This paper will report multi-tasking technology and elemental technology used in this machine.

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Hybrid micro-machining is the most promising technology for the production of miniaturized parts and this technology is becoming more and more important and popular because of growing demand for industrial products with not only increased number of functions but also of reduced dimensions, higher dimensional accuracy and better surface finish. In order to achieve meaningful implementation of micro-machining techniques, this research seeks to address four important areas; namely (a) development of machine tool capable to do both conventional and non-conventional (b) process control, (c) process development to achieve necessary accuracy and quality and (d) on-machine measurement and inspection. An integrated effort in these areas has resulted in successful fabrication of micro structures that is able to meet the miniaturization demands of the industry.

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In recent years, diversification of consumer needs and ephemeralization of a product life cycle is progressing in Japanese industry. As a result, the production system has changed from high-mix low-volume production manufacturing to variant types in variable quantity. The cell production system is paid to attention as a production system to achieve variant types in variable quantity. There are a miniaturization and a process consolidating of the machine tool as needs of the cell production system. The processing to the small part was assumed, and a compact size, light small power diode laser of 50W was used as a heat source of this system. In this research, a multifunctional machine tool of a desktop size in which the cutting function and the heat-treatment function with the Koide power semiconductor laser were consolidated was made for trial purposes. The practicality to the cell production system and the superiority of this machine to the environment load were examined.

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In order to level up the 3D complex shape machining for the metal mold and die, the machining simulation which can be considered the contact point or relative angle between the workpiece and machining tool is useful. In this study we has been developed the technique which calculates the interference quantity of the cutting edge and the workpiece for the ball-nosed end milling. In this report the new machining test method at any tool orientation used by 3axis controlled machine tool is presented, and the relationship between machining accuracy and the tool orientation and the cutting force is discussed.

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Ball end milling is widely used in the manufacturing process of sculptured surface. In order to achieve high productivity and high accuracy with low costs, it is necessary to know the cutting properties before manufacturing. This research makes an effort on finding out the influence of shape of workpiece on machining error in ball end milling of cylindrical surface. At first, the machining errors in ball end milling of convex and concave cylindrical surfaces are analyzed theoretically, respectively. Secondly, the experiments are carried out to verify the theoretical results. At last, the appropriate cutting conditions are discussed basing on the calculated and measured values.

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Ultra precision steel cutting using geometrically defined single crystal diamond cutting tools is normally handicapped by excessive chemical tool wear. But when the ultrasonic elliptical vibration cutting is applied, it has been reported that tool wear is considerably reduced and fine surface was obtained. The reason is thought to be because the cutting takes place intermittently, and reduces chip thickness and cutting force. End milling is commonly used to produce micro free curved surfaces. This method is one form of intermittent cutting, and chip thickness can be controlled. In this paper, end milling was performed to cut steel. The work material was stainless steel (SUS420J2) 2 mm × 5 mm in size. The major experimental conditions used were a clearance angle of 20°, a swing radius of 2 mm and a rotation rate setting of 100,000 min^<-1>. The experimental results show that tool wear was reduced and machined surface had high surface quality under those conditions.

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The micro-scale grooves are machined on the glass plates with the inclined ball end mills. This study discusses the effect of the tool shape on brittle fracture to improve the material removal rate. A large edge roundness, which can be controlled by honing, suppresses the crack propagation. However, the effect of the edge roundness reduces with the cutting length; and disappears in the long cutting length due to the tool wear. The effect of the tool stiffness on brittle fracture is also studied in the vibration tests and the cutting tests with changing the under-neck length. The maximum feed rate for finishing a crack-free surface increases with the tool stiffness.

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A 5-axis simultaneous controlled machine tool is built up to machine the micro-scale structures on brittle materials in milling. The on-machine measuring system is developed to measure the alignment error in the setting of the workpiece and surface profile after machining. A confocal laser displacement sensor is mounted on the head of the machme tool in the measurement. The alignment error can be compensated by the coordinate transformation based on the measured data. The glass milling is performed to verify the error compensation with the developed measuring system. The machined profile can also be measured with the laser scanning on the surface.

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In machining, controlling the friction at the tool-chip contact area is an important factor. It is well known that microscopic textures on the solid surface often improve the frictional characteristics. Thus, microscopic textures fabricated on the tool rake face are expected to reduce the friction coefficient at the tool-chip interface. For this reason, using sputtering, photolithography and wet etching techniques, nano/micro-scale steps were fabricated on the tool rake face near the cutting edge where a produced chip makes a contact with the tool during machining. Orthogonal cutting experiments were carried out using the fabricated tools and the cutting forces were measured. As a result, it was found that the width of the steps and the distance from the cutting edge to the step had direct influences on the reduction of the friction coefficient.

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The frictional stir burnishing can give frictional heat and large stir, to the surface of work pieces. Those factors made enhanced layers on some of steel materials (S45C and SUS304). The enhanced layers are observed clearly in cross section of processing surface by optical microscope in those cases. S45C carbon-steel was hardened and its hardness is over 900HV. It is thought that the main factor that the hardened layer was obtained is martensitic transformation. SUS304 stainless-steel which can be not given heat-treatment for transformation was also hardened. It is thought that the factors that the hardened layers were obtained is grain refinement or deformation induced transformation.

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This paper shows a micro fabrication to control the functionality on a surface. The surface functions are controlled with the shape and the alignment of the micro-scale structures, which can be machined in the incremental stamping with the structured tool and the plastic molding. The effect of the pillar shape and the alignment on wettability is measured in the droplet tests. The contact angle on the cylindrical pillars array with isotropic alignment follows the Cassie-Baxter model well. The wettability is also observed on the plastic plate deposited by the thin metal layer. The surface property changes from hydrophobic to hydrophilic wettability with decreasing the contact angle. The structured surface deposited by the thin gold layer also changes the wettability with the solid fraction.

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This paper discusses the design of structured surface to enable quick removal of the liquid on it. Conventional measurement of contact angle and/or sliding angle does not necessarily give actual evaluation because of the liquid volume is limited to several iiL. In this paper, water or oil of 3mL was poured over the structured surface that made of polydimethylsiloxane and the total area of residual droplets was calculated from the captured image with camera. The pattern was line-and-space with rectangular cross-section of which dimension was sub-millimeter order. The pattern was oriented in parallel or perpendicular to the flow. V-arrangement converging to the flow direction was also tried. It was found that V-arrangement was effective both for water and oil. The appropriate dimension was 100mm in depth, width and height.

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Micro chemically Ni-P plated diamond tools were developed and the crystal structure of plating layer was made clear. Drilling and grooving characteristics of single crystalline silicon and quartz glass were examined using these tools regarding machining mode, tool life, hole diameter change, product quality, etc. As a result, the tool life in grooving glass was almost an half of that in silicon, which may result from the thermal conductivity. In helical drilling of silicon more than 800 holes could be machined at the maximum.

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Micro ball endmill with a tool tip radius of 50 μm was formed using binderless poiy crystalline diamond (PCD) and binderless cBN as tool materials. Which is similar to that of single crystal diamond tool, smooth and sharp cutting edges without micro chips could be formed. Cutting test revealed that binderless PCD was effective for the interrupted cutting of hard and brittle materials such as glass-like carbon and cemented carbide.

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Magnetic compound fluid (MCF) is expected for the use in the ultra-precision surface polishing process of three-dimensional shaped components. The MCF shows the action of accumulation and particle disposition under fluctuating magnetic field, and generates the high restoring force. In this paper, the effects of the MCF composition on the polishing characteristics under fluctuating magnetic field were experimentally investigated. The obtained results showed that the Magnetic Fluid (MF) included in the MCF accelerated the particle disposition once a fluctuating magnetic field is applied, thus generates the high restoring force and increases the polishing performance. The α-cellulose in the MCF not only increased the shearing force but also retain the fluidity, thus improved the polishing performance.

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Recently, many micro processes have been developed for fabricating various types of micro elements and systems. In this study, single point incremental forming, in which any die or any backing plate was needed, was developed for fabricating thin shell structures. It was found that the accurate sensing of contact between the tool and blank, and the selection of proper forming conditions resulted in the elongation of forming limit. Then, micro 3D shell structures of aluminum foil 12 micrometers thick were formed successfully on a blank without any die or any backing plate. Finally, incremental forming of miniature pyramid with a base of 1 mm x 1 mm was conducted on an ultra thin pure gold foil 2.5 micrometers thick.

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This paper deals with cutting phenomena in micro end milling. Cutting experiment was conducted by small milling machine and micro end mill was used. Tool wear and surface roughness were measured in interval of constant cutting length. Cutting force components were measured by dynamometer. As the results, rotational speed at which tool wear was minimized existed in this experiment and feed rate hardly affected on tool wear. Surface roughness at bottom was deteriorated by interference between tool edge and bottom of work, caused by deflection of tool.

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An increased on demands of aerospace components has lead to implementation of high speed machining (HSM) coupled with dry or near dry machining to increase the productivity. In this investigation, the effect of high speed drilling (HSD) conditions on the performance and surface integrity of titanium alloys were studied. Cutting forces and temperature were determined as a function of the two control parameter. A cursory metallurgical examination was made on the holes surface. The results of the investigation showed an increase in cutting temperature with increasing cutting speed and feed. Thrust force and torque decreased linearly with the increasing cutting speed but significantly increased when higher feed is employed. The surfaces of the specimens were examined under the scanning electron microscopy (SEM) and the hardness was measured using microhardness tester machine.

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A great compressive residual stress is generated within the drilled surface layer, and hardness increases with the work- hardening in drilling of the high hardness material. If these functions can be positively given, the additional process such as shot-peening becomes unnecessary. Then, the conditions to give these functions by drilling was found from the change in the microstructure of drilling conditions and the drilled surface layer, and the relation among generated change in the microstructure and the residual stress, hardness, was found in this research.

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It is well known that the elastic deformation caused by cutting force and the thermal deformation caused by temperature rise are considered to be the main cause of the machining error during the fine boring process of the engine cylinder. In this study, to clarify the proportions of thermal deformation and the elastic deflection in the total machining error, a new experimental method (YAG laser heating experiment) to investigate the influence of thermal behavior on machining error solely was developed. Then, FEM analysis and experiments were carried out (900m/min, F=0.2mm/rev, D=0.3mm, Dry Cutting). The result shows that the deformation caused by the thermal expansion is larger than that caused by the cutting force.

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Rotary cutting using a milling spindle on the multitasking lathe is expected to achieve high speed and high efficiency machining of high-temperature alloys for aerospace industries. This paper discusses effects of cutting speed and the rotating speed of the circular tool on the cutting point temperature and tool surface temperature. And also the effect of the groove type chip breaker for the machining of Incone1718 is discussed. It is shown that the cutting point temperature is kept rather low during the rotary cutting comparing with the conventional cutting. And the chip breaker works at the higher cutting speed of 500m/min.

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To make clear the relationship between machinability of aluminum alloys and adhesion on tool face, some annealed aluminum alloys has been machined at dry cutting using lathe under condition to cause adhesion on cutting tool more remakably. As a result, it was found that the surface roughness of longitudinal direction on work is controlled by both adhesion on rake face and on back rake face of tool. And, the surface roughness of transverse direction on work increased with increasing the adhesion on bake rake face of tool. Moreover, machined chip increased remarkably when fracture energy is more than 50 kJ/m^3.

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CFRP (Carbon Fiber Reinforced Plastic) has higher specific strength, modulus of elasticity and so on. CFRP is, however, well known as difficult-to-cut material which has very strong physical and mechanical characteristics. Drilling technique of CFRP which is one of the most important cutting operations is currently carried out in industrial factories. In this research, we tried to make high accuracy drilling process by helical movement method of cutting tools on the CFRP plates. Cemented-carbide ball-nose end mill is suitable to drill out thin CFRP plates which dimension of L/D (Length per Diameter) is below 0.3. On the other hand, it is not easy to make drill holes on the thick CFRP plate by ball-nose and square end mill because of inefficient evacuation for cutting chips.

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This study describes a new method for micro-pin electrode formation and its application to micro machining of insulating ceramics. The rotating electrode is moved through the inside of the working plate with scanning EDM, then it changes into a micro-pin with a very small diameter. Two electrically isolated plates were set in position, and movement of the electrode is controlled to maintain a centered position by measuring current to the isolated plates. Machined diameter closely corresponded to the desired diameter. A micro hole of 30μm diameter was drilled into insulating Si3N4 ceramics using a formed micro-pin electrode.

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In single discharge with rather high discharge current and with a thin tungsten elecirode, a very thin, needle-like shape can be formed at the tip of the electrode. Accuracy of this needle diameter is important to apply for actual products. Although discharge current is rectangular pulse in our previous experiments, this time, stepped pulse is applied to change the effect of input energy distribution, and then the needle diameter is examined. In single discharge of the stepped pulse, thin needle is formed and Standard deviation of the needle diameter was able to be made small.

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Insulating ceramics can be machined by EDM machine with the assisting electrode method. In this method, the formation process of the electrical conductive layer on the workpiece is the most important factor. The EDMed workpiece is covered with cracked carbon that is generated from the dielectric oil during discharge. Machining atmosphere contributes to the formation process of carbonic layer. To clarify the influence of machining atmosphere in assisting electrode method, the effect of temperature, kinetic viscosity and cooling property of dielectric oil was investigated using the designed test machine system. The correlation between properties of the dielectric oil and material removal rate were revealed with the four types of dielectric oil. The optimum kinetic viscosity value was observed in the same compound oils. Elongated long pulse accelerated the material removal rate using some oil that had the good cooling capacity.

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Powder suspended EDM are know as a method which can finish mirror-like surface by EDM. One of a reason is that, electrical discharge was dispersed using powder suspended fluid. But the roughness of machined surface was different when a several powders mixed, so the influence of gap phenomenon was not apparent. In order to vary the gap phenomenon under the powder suspended EDM, the gap region observed using a high-speed camera system. This report describes the observation result with powder suspended EDM.

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Conventional five-axis machining centers with a tilting rotary table have two rotary axes parallel to linear axes. Recently, some machining centres with an inclined A-axis are developed. However, there is no method for measuring the deviations inherent to this type of machines. A new measurement method is proposed as well as the identification method. It is found that the inherent deviations can be identified by carrying out simultaneous three-axis motion for the C-axis and simultaneous four-axis motion for the inclined A-axis.

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Cone frustum machining with simultaneous five-axis control, which is prescribed in NAS979, is one of the most general method for the accuracy test of five-axis controlled machine tool. And instead of the machining, the measurement with double ball bar device has been proposed. In our previous work, we showed that the geometric errors between feed axes in five-axis controlled machine tool influence the accuracy of machined cone frustum, and it depends on the location, apex angle, tilt angle or diameter of the cone frustum. It indicates that all geometric errors might be identified with the profiles of cone frustum. In this paper, we suggest a method to identify the geometric errors in five-axis controlled machine tool with tilting table using the multiple motion trajectories of cone frustum machining measured by double ball bar device.

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Five-axis machining centers are normally classified into three structure types which are Tool-tilting-, Tool-Work-tilting- and Work-tilting-type. They are basically designed from conventional three-axis machining centers by addition with two rotational slideways. In this research it is described that the affect of structure errors on all kinds of five-axis machining centers which are working well for five-face machining is analyzed by form-shaping function. It is found that five-axis machining centers have nine variation of structure type. Normal Work-tilting-type of five-axis machining center is not exactly better structure than new proposed structure type in view of machining errors.

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In this study, mathematical models for the rotary table driven by roller gear cam and direct drive motor applied for 5-axis machining centers are proposed. The table driven by the roller gear cam is modeled as three degrees of freedom system. This model consists of rotary motion of motor, rotary motion of table and linear motion of globoidal cam. On the other hand, the table driven by the direct drive motor is modeled as single degree of freedom system. In order to evaluate the effectiveness of models, the frequency response, the step response and the pitch error of uniform velocity motion are measured and simulated. The influences of the unbalances mass are also measured.

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This paper proposes the improvement method of angular positioning of tilting rotary table in 5-axis control machining center. Angle deviation of the tilting rotary table caused by moment load of workpiece fixed on the tilting rotary table is a major disturbance to machining accuracy in 5-axis control machining center. However, factors related to this problem have not been clarified. Therefore in this paper, angle deviation and drive torque are measured under tilting rotary table added moment load. From a experimental results, experimental model as a function of angle deviation, moment load and drive torque is obtained, and angle deviation is estimated by using proposed model accurately.

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To clarify the point to note in measuring geometrical deviation of five axis MC by simultaneously three axis movement using the double ball bar, we carry out following evaluation. 1. Reproducibility of measurement. 2. Reproducibility of alignment accuracy between the center of ball on the spindle side and center of C axis. 3. The influence of C-axis rotation to the alignment accuracy. 4. The influence of range of measurement angle on the calculated value of track center. As a result the notes to be considered in measuring are made clear. The factor of influence to the measurement precision is shown, and the note to high accuracy measurement is examined.

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We developed an ISO draft proposal for testing the kinematic accuracy of five-axis machining centers. The draft proposal consists of the existing document of ISO 10791-1 for three axis machines and three normative annexes for five axis machining centers. In the annexes, five testing objectives and their tolerances corresponding to structural configurations are proposed. The kinematic tests include two-axis motion, three-axis motion and five-axis motion. The object of the two axis motion is to check the synchronous accuracy of a linear axis and a rotary axis, and the object of the three-axis motion is to check the geometric accuracy of two-linear axes and one rotary axis. Two kinds of five-axis motions is also defined. One motion is to check the overall geometric accuracy and the other motion is to check the overall kinematic accuracy.

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In this paper, NC data for three-dimensional circular movement under simultaneous five-axis control were prepared by using a CAM software and a theoretical method, and the velocity changes of the NC data were precisely investigated. Then, using the simulator of five-axis machines, trajectories were compared. It is found that higher feed rates are limited to avoid rapid change in velocity in the NC data produced by the CAM and, as the result, the trajectories are affected by the feed rates programmed.

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