This paper describes an innovative method to machine the guide rails for elevators in high efficiency and high accuracy. Guide rails are usually machined on a planer. However, the machining time is long because of the useless return motion of the table and low cutting speeds. In order to decrease the machining time, face milling with combined cutters was applied to the machining of guide faces. The trial face milling of guide rails indicated the reduction of the width of guide rails at the tool exit and deterioration of the perpendicularity of guide faces. Thus, in this research, the machining mechanism affecting the accuracy of the machined surfaces was studied. The analytical and experimental results revealed that cutter path deviation from the center of a guide rail affects the width reduction at the exit part of the guide rail, whilst the clamping stiffness of the guide rail has a much greater influence on the perpendicularity of the guide face than the cutter path deviation. It was also found that change in the number of cutting edges engaged in machining simultaneously caused wavy machined surface with a long wave length. Finally, determined based on the above findings were the critical tool path deviation and critical clamping stiffness, which permitted the efficient machining of the guide rails at a high cutting speed of 267m/min and a high feed rate of more than 1000mm/min, decreasing machining time by a factor of six.

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This paper deals with machinability in high-speed face milling of gray cast iron to which small quantities of Al and Mg were added. The machinability of Al-Mg-added gray cast iron was evaluated in face milling with cermet inserts at cutting speed from 100 to 1000 m/min in comparison with conventional gray cast iron and Al-added gray cast iron. In the face milling of conventional gray cast iron and Al-added gray cast iron, the wear increased significantly as the cutting speed increased. The wear pattern of tools in the milling of these irons were almost the same, and the thermal cracks similarly occurred in both cases. On the other hand, the addition of both Al and Mg has drastically decreased the wear rate and the wear hardly progressed even in prolonged cutting length after initial wear. The amount of the adhesion on tool faces increased as the cutting speed increased. The adhered layer mainly consisted of the elements added to the work material. As this result, the increase cutting speed resulted in the thick adhered layer and the reduction of tool wear. Furthermore, the small addition of Al and Mg prevented the thermal cracks in the face milling of the gray cast iron.

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Surfaces of optical parts are required to be smooth. Therefore, polishing is carried out. The period of polishing process depends on the roughness of ground surface. To shorten the period of polishing process, the roughness of ground surface must be smooth. In this paper, to clarify the optimum grinding condition, maximum height roughness of traverse ground surface is analyzed theoretically utilizing the statistical grinding theory. From the view point of relationship between the grain cutting direction and workpiece feed direction, the grinding condition is classified into parallel grinding and cross grinding. And it is found that the parallel grinding has an advantage in rough grinding, and the cross grinding is suited to finish grinding.

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Surface acoustic wave (SAW) linear motor is a kind of ultrasonic motors. The advantages of the SAW linear motor are thin structure, high force, high speed and precise positioning. On the other hand, the motor has a problem with wear of contact surface. The SAW linear motor consists of a LiNbO₃ substrate as a stator transducer and a silicon substrate with distributed projections as a slider. However, the stator transducer material is easy to wear out due to friction drive. Moreover the silicon projections may enhance the wearing. Lifetime of the motor is reduced by the wear of the stator. To solve this problem, previously, segment-structured diamond-like carbon (S-DLC) films have been applied to the stator transducer surface. However, reduction of driving performance with S-DLC films stator was observed. Nonuniform shapes and heights of the segments are considered as the reason. Additionally, exfoliations of the S-DLC films were observed. The reason of this problem was that interlayer between the S-DLC films and LiNbO₃ substrate was not optimized. In this report, we propose a new S-DLC transducer. This paper presents the new method, fabrication of the stator transducer and abrasion test result. Driving characteristic with the stator is also reported.

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By using a cutting model and energy method proposed in previous papers, cutting forces in various milling processes in which both cutting edges of spherical and cylindrical portions engage with the workpiece can be predicted, and distribution of cutting forces along the cutting edge also obtained. To clear the behavior of tool deflection and the mechanism of machined surface generation in milling along a contour line of an inclined surface, FEM model of a ball end mill is constructed by using geometrical data of cross section of the tool. The tool deflection and locus of tool axis during milling are analyzed by using the cutting force data predicted and the FEM model of a ball end mill. In the analysis, radial force components distributed along the cutting edge are applied to the FEM model and support condition of the tool is experimentally determined on the basis of a bending test of a cylindrical bar conducted on machine tool. Tool deflection and behavior of the tool axis during contour milling of inclined surfaces is measured by using an eddy-current type sensor and compared with the predicted results. The predicted results are in good agreement with the experimental results. It is shown that the tool deflection and behavior of the tool axis vary considerably with the feed direction of the tool. For milling an inclined surface where the left side of the feed direction is higher, the tool axis deflects to be drawn toward the inclined surface.

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It has become a recent trend to apply a special environment into a lithography tool, for instance, immersion, EPL (Electron beam Projection Lithography) and EUVL (Extreme Ultra Violet Lithography) in order to exposure less than 22nm line and space at semiconductor industry field. For a cooling system that a heater is surrounded by metal can and a coolant is supplied into the can by using movable tubes, not only flexibility, damping, durability, particle protection and anti-liquid, etc, but also pressure-resistance, low outgasing and low leak from connections, etc might be strongly taken into account for vacuum lithography. Especially, because a coolant leak is very critical for EUVL in which a partial pressure of several molecular is strictly restricted, a special tube and joint have to be required in the case of liquid cooling system. On the other hand, a gas cooling can be one candidate because of a lower leak damage, however it is necessary to compensate its low cooling efficiency of gas system by using temperature feedback control. In this paper, two guide lines of a cooling mechanism for wafer and mask stage of vacuum compatible tool, a liquid cooling and gas cooling system are introduced.

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Polymeric composites, i.e. epoxy resin and polystyrene including an ionic liquid of BMImBF₄ have been prepared and characterized in terms of their tribological properties. The addition of BMImBF₄ up to 20 wt% has achieved to improve lubricity of the polymeric matrices in both air and vacuum without detrimentally degrading mechanical strength. BMImBF₄ has been stored in pores distributing inside the polymeric matrices. As little chemical reaction between epoxy resin and BMImBF₄ has revealed by Fourier transform infrared spectroscopy, BMImBF₄ would work as a lubricant after seeping from the pores due to the transformation and/or the slight wear of the surface of the polymeric composites. Furthermore, coatings of the epoxy resin including BMImBF₄ on silicon plates have shown low frictional properties regarding thickness raging from several to 600 μm. The coating has also performed self-lubrication on acrylic resin as well as steel previously coated with epoxy resin to avoid chemical reaction with BMImBF₄.

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In this paper the effectiveness of the binder-less PcBN tool with a sharp edge in the high-speed machining of soft magnetic materials. By using the binder-less PcBN tool with high-temperature hardness and high bending strength, we studied the effect of rake angle and cutting speed on the surface machined under a high-speed cutting condition. We then found that the surface roughness was reduced at a rake angle of -5 degrees by the increase of the cutting speed. On the other hand, the flank face wearing rate at a cutting speed of 20m/s decreased to 1/2.5 of the rate at a low cutting speed. The tool flank face wearing rate in the high-speed machining of pure iron, a major component of the work-piece material, was extremely higher than the rate in the machining of soft magnetic materials. It was found that the resin component of the work-piece materials remaining on the flank face in a graphitized form prevented the reaction between the binder-less PcBN tool and the iron, the main component of the work-piece materials.

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Milling is one of the most important metal cutting processes. If we measure the cutting force, we can make cutting process optimum, prevent tool breakage, and improve efficiency of process. However in the case of using an end mill with small diameter, it is very difficult to identify whether cutting process is good or not.
In this paper, we proposed the cutting force measurement technique by using image processing. In the technique, we captured a image of the end mill during cutting process, determined deflection of the tool and then estimated cutting force. Finally, we can estimate small cutting force with high accuracy.

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This paper presents novel methodologies for a rheology-based rolling friction modeling and its parameterization in ball screw-driven table systems. The rolling friction exists in the table drive mechanism as a nonlinear component, which deteriorates the control performance in the fine positioning. The rolling friction behaviors, therefore, should be clarified to provide a precise numerical simulator and to design effective compensators. In the rolling friction modeling, a rheology-based friction model is introduced, considering the characteristics of contact points at the friction surface. The proposed friction model, in addition, is formulated by a neural network (NN), where the network parameters can be identified to express the actual friction behaviors. The proposed rolling friction modeling has been evaluated by a series of numerical simulations and experiments using a prototype for industrial positioning devices.

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A new planar multi-link model is given for a fishing-rod tackle in orderto analyze its nonlinear dynamic behavior. In this theory, the rod and the line are modeled as united multiple rigid bodies. A method adopting a lower triangularization of a sparse symmetric coefficient matrix of linear equations is proposed for dynamic tackle-simulations. Relevant parameters such as drag coefficient and damping coefficient are identified through rod vibration experiments. The numerical solutions describe the vibration of the rod-tip and the large deformation of the line under the water. The results of this paper show that the water depths of main sinker play significant roles for the rod-tip response through a larger damping force for a deeper sinker. The response of the rod and the variation of the line shape caused by the fish-bite are demonstrated, similarly.

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A vertical-scanning shape-measurement interference microscope using white light is widely used to measure 3D shape of a small object. This microscopy however cannot be used in vibrating environment. Because it is required to repeat one-way vertical movement of the predefined length and interferogram recording after that. We are researching a new technology which can accurately measure the real-time changes of optical path difference (OPD) and can trigger the recordings. When a rough surface is observed under the microscope, an interference pattern has very complex structures. To measure OPD change from the pattern, we use flexible masks to extract components of cosine change and sine change from the complex-structure change. Using the extracted changes we can obtain continuous phase change over a 100-μm vertical movement. But, the total phase change of the movement slightly depend on roughness of the measured area. This dependence is showed to be affected by a numerical aperture of an object-lens and can be reduced using a smaller aperture lens.

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In this paper, a novel approach for designing grain patterns based on digital technology is proposed. A digital tree is raised according to weather data such as daylight hours, precipitation, and temperature obtained from public organizations, and grain patterns are then formed as the cross section patterns generated by cutting the trunk of a digital tree. In order to simulate tree growth, digital trees are constructed as an electric charge model in consideration of dendrological characteristics and environmental conditions. A basic system based on the proposed method is developed and it enables one to make grain design as the cross section patterns of various types of digital trees which are obtained by changing growth conditions such as the growth period, the growth location and the slope angle of a growth place.

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