In the previous papar, we have proposed a feedback superposition method to nonlinear vibration system whereby exact determination of the functional structure for periodic solution can be realized. Meanwhile, regarding a specific nonlinear system having no stiffness such as a stiffness-free impact oscillator, we have to analyze unconverged functional series. In order to solve this problem, we propose in this paper an advanced superposition method by applying Cesàro's summation technique. Through this approach, we can obtain fundamental periodic solution for the stiffness-free impact oscillator. This symmetric solution can be explicitly represented for the functional structure which has not been available by former approach such as the patching solution method. Finaly, we found that the impact oscillator system can be evaluated in terms of (C. 1) summation to the viscous-damped system and (C. 2) summation to the undamped system, respectively.

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A new analytical method to find the exact solution to nonlinear impact oscillator system having no spring stiffness is proposed. In this study, we apply the pseudo feedback superposition method in order to derive the fundamental form of unconverged periodic fundamental series which inevitably appear through the analysis. First, for this stiffness-free impact oscillator we assume the solution facing towards the future. Under this assumption, we have to evaluate unfavorable two terms ; “trend” term and “offset” term which lead to failure of periodicity and symmetricity among the solution. Second, we propose an alternative method to derive corrected terms based on the evaluation of only finite terms summation. Solution calculated through the approach can be indentical to that through Cesàro's summation approach reported in the previous paper. According to the proposed solving procedure, it is also found that the derivation of the periodic solution calculated through the conventional patching method assures the approval condition to the periodic solution.

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Vibrational mechanisms of flow-induced vibration of a coil spring due to fluid flow were investigated and the mitigation methods were suggested. At first, as one of those vibrational behaviors, flow-induced vibration of a coil spring with a circular rod in the middle of it due to an axial flow was investigated experimentally using fundamental test apparatus. The effects of stiffness of springs, gap between springs and inner rod and initial compression of springs on the vibrational behavior were clarified, and a stability diagram is presented for the spring vibration. Based on the experimental results, the vibrational mechanisms of the coil spring with an inner rod were investigated. Finally, a design instruction on the mitigation of flow-induced vibration of coil springs including the cases of cross-flow-induced vibration and the axial-flow-induced vibration of a spring without an inner rod was summarized and suggested.

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This paper describes frequency entrainment in self-excited oscillators which are mechanical vibration systems controlled by velocity feedback with variable gain. The oscillators are in a state of self-excitation, or in a state of vibration suppression by velocity feedback gain. When external force to the oscillator is small, the velocity feedback has a positive gain and self-excited vibration is generated. When external force is large and the vibration amplitude of the oscillator reaches the reference only by forced vibration, velocity feedback suppresses vibration actively, and then frequency entrainment occurs (forced entrainment). The synchronization limit of forced entrainment is derived from the resonance curve of forced vibration. Frequency entrainment in the plural oscillators (mutual entrainment) can be treated as force entrainment by substituting external force for the interaction of the other oscillator.

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A soot blower is used to blow off soot on tubes in a tubular heat exchanger. or a gas heater. The soot blower has a long flexible tube, that is, a lance tube, 8 in long and 76.2 mm in diameter, which is put slowly into/out of a gas heater. Stearn flows through the lance tube and is discharged at the free end to blow off soot. The lance tube, rotating slowly about its axis at about 12 rpm, is supported at an intermediate position by a support bearing, that is, a lance bearing. Vibrations and noises occurred in operation while a lance tube is being put into a gas heater slowly. They are considered self excited vibrations due to friction between the lance tube and the lance bearing. From frequency analysis dominant frequencies of the observed vibrations are the eighth to tenth natural frequencies. Experimental study is clone to clarify the mechanism of the vibration. Accordingly. backward whirling motion of a shaft is observed. As the clearance between the flexible shaft and the circular support is reduced, higher modes appear.

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This paper concerns the minimizaton of acoustic potential energy in a strongly coupled structural/acoustic enclosure using both active noise control (ANC) and active vibration control (AVC) A target enclosure is composed of rigid walls and a flexible panel that is subject to external forces. First, optimal feedforward control law to minimize the acoustic potential energy in the enclosure is derived using control actuators for AVC and acoustic point sources for ANC situated at arbitrary locations. It is found that acoustic control power becomes zero under the optimal condition even in a strongly coupled enclosure as in a weakly coupled system. It is also found that under the minimization of acoustic potential energy, vibration control power becomes zero. Numerical simulation is carried out, demonstrating the control effect for minimizing acoustic potential energy using both ANC and AVC. Finally, synergy effect of ANC and AVC is clarified, intriguing phenomenon due to the effect being investigated.

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Seismic ties are connecting devices installed between boiler and its supporting structure in thermal power plants. The seismic ties are made of steel and allowed to be used in the elasto-plastic deformation region in order to reduce the seismic response of the boiler structure. This paper deals with a study on vibration energy absorbing performance of elasto-plastic behavior of the seismic ties based on vibration energy balance equations of boiler structures using experimental proof vibration data obtained from a large shaking table.

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A simple and stable energy-storage flywheel system with high temperature superconducting levitation is presented. In order to have stable levitation, a superconductor and a permanent magnet are used, and 3 permanent magnets support the top of the shaft. In the part of drive system, 8-poles permanent magnet and 8 coils are used to cancel electromagnetic forces in the radial direction. An electromagnetic damper consisting of permanent magnet for levitation and 4 coils is presented which lies at both ends of the shaft. When the shaft vibrates in the direction perpendicular to the shaft axis, current flows in the damper coil. It generates the electromagnetic force. The force is in proportion to vibration frequencies of the shaft, so that the force behaves like damping forces. Using this system, a control like the sensorless control is performed. Experimental tests have been carried out for the system as just mentioned. It is clarified that our system has stable levitation, and vibrations are suppressed significantly.

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Tainter gates at Folsom dam in California have an inclined circular-arc skinplate which undergoes a streamwise rotating vibration, thus inducing an excessive push and draw hydrodynamic pressure. In order to calculate the in-water inherent vibration frequency of the skinplate, such a vibration-induced hydrodynamic pressure acting on the inclined circular-arc skinplate has to. be analyzed first. This study presents an empirical evaluation method of the push and draw pressure induced by the streamwise rotating vibration of the inclined circular-arc rigid skinplate, which is based on the theoretical results for the vertical flat and rigid weir plate undergoing the streamwise rotating vibration. Subsequently, the exact equation of motion of the skinplate is derived, and the in-water free vibration tests of 1/30-scale skinplate model of Folsom Tainter gates are made to verify the derived equation of motion for its validity.

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Pressure fluctuation occurs in an oil pressure pump in the nature of the machine. It becomes a cause of a vibration and a noise of a building where the oil pressure pump are set because the pressure fluctuation gives a fluctuating force on floors and walls of the building. So it is important to reduce the vibration and noise from an environmental point of view. A side branch is often used to reduce the pressure fluctuation because of its simplicity and its effectiveness. In this paper, the side-branches are applied to the real pumps and the reduction effects are described. As 2nd and and harmonics of the pressure fluctuation are dominant in this pump, two side branches are used to reduce each harmonics components respectively. As a result, the vibration of wall and the interior noise of the room were suppressed violently. And it was clarified that the reduction mechanism is not resonance but the superposition of two fluctuating weves which are the progressive and reflective waves.

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Rubbing between a rotor and a stator causes the characteristics vibration to the rotating machinery. Rubbing mainly occurs at the seal part and the blade tips. Since many sort of materials are used on the seals, the friction between a rotor and seals have also various coefficients. In case of the high friction coefficients it is easy to induce the backward whirl by the rubbing, while in case of the low friction coefficients the backward whirl may not be caused in spite of existing of the rubbing. The narrower the whirl orbit, the greater the contact force is. In this paper, these behaviors are confirmed experimentally and theoretically.

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This paper considers a design method for delayed-inverse systems for time-invariant strictly proper digital systems, which exactly reproduce the input with some delay. The inverse system must be stable in practical applications. It is well known that the inverse system is unstable if the system has invariant zeros outside the unit circle. The purpose of this paper is to give a state space design method for stable delayed-inverse systems such that the series-connected system, which includes the system and the stable delayed-inverse system, is a diagonal rational function. As a preliminary, we construct the delayed-inverse system by the usual method and factorize the delayed-inverse systems into several subsystems. The stable delayed-inverse system is obtained using observer design for subsystems of the delayed-inverse system. A simple numerical example is also shown.

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This study demonstrates the applicability of PCB monitoring using laser ionization time of flight mass spectrometry. Picosecond 266 nm laser light ionization reduced fragmentation, with PCB detection sensitivity under ppbv (-μg/Nm³) that can be achieved in one minute detection time. This has great advantages in terms of real time monitoring ability compared to the conventional method, which requires several days analysis time. A prototype of the PCB monitoring device has been developed and tested in Mitsubishi Heavy lndustries' PCB treatment plant. The one-minute detection time represents a substantial advance in the monitoring of exhaust gas and in compliance with safety regulations in the atmosphere surrounding work areas where PCB vessels are dismantled.

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Power-assist system technology and its applications to manufacturing systems, constructing systems, rehabilitation and welfare services have attracted special interest recently. For example, automobile assembly processes utilizing power-assist systems exist. However, the effect of such uncertainties as Coulomb friction on the power-assist systems has not been fully addressed. This study proposes a controller design method for the robustness improvement of power-assist control. Especially, we pay attention to the influence of uncertain Coulomb friction and design the servo control system consisting of two parts. The first part is an on-line impedance control simulator which works as the reference generator. The other one is a sliding mode controller to suppress the errors between the references and corresponding responses. By applying the method to the positioning problem of a cart, the effectiveness of the method is verified by experiments.

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Force measurement method by using a carbon nanotube (CNT) probe with pico-Newton (pN) order resolution is presented. A CNT probe is constructed by attaching it to the tip of a tungsten needle probe or an atomic force microscope (AFM) cantilever by using nanorobotic manipulators inside a field-emission scanning electron microscope (FE-SEM). Electron-beam-induced deposition (EBID) is used for fixation of CNT probes. For manipulating them easily and quickly, CNTs are dispersed in enthanol by ultrasonic waves and oriented on copper electrodes by electrophoresis. The elastic moduli of CNT probes are calibrated by exciting the probes at the fundamental frequency by applied electric field, for force measurements. We analyzed the resolution of force measurement method using a CNT probe. This method can be used to measure the mechanical properties of nanostructures and friction or exfoliation forces in nanometer order.

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In order to develop a human friendly support machine for elderly people, improvement of the interface between human and mechanical system has been becoming very important. Especially, soft mechanical interfaces are strongly required in motion assist machines for handicapped people or elderly people. Therefore, an actuator that has both active elements and passive elements attracts attention to design the soft mechanical interface. To realize these elements, we propose a new type of pneumatic soft actuator that a sponge rubber is covered with silicon rubber (Silicon Outer Fence Mold Actuator). In this paper, the structure of the actuator is explained. Furthermore, it is clarified that the characteristics of the actuator are influenced by the number of sponge layer and sponge material. Moreover, we clear position control performance of the actuator. That is to say, the effectiveness of the proposed actuator is cleared through some experimental results.

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The elastic parameters of skis are essential for simulation on skiing. Generally, the elastic parameters of skis have not been reported. Also, the elastic parameters of skis are difficult to determine by either theoretical and experimental approach. Therefore, an inverse analysis method to identify equivalent elastic parameters of skis is very important. In the identification method, mainly, the experimental modal analysis technique, the finite element method and the sensitivity analysis method are used. First, by applying the experimental modal analysis technique to a ski with free boundary conditions, natural frequencies and mode shapes are obtained. Secondly, from the obtained natural frequencies and mode shapes, the equivalent elastic parameters of the ski are identified numerically. Finally, to justify the application of this approach, the bending stiffness and twisting stiffness in longitudinal direction calculated by the obtained equivalent elastic parameters of the ski are compared with those obtained by the other experimental method.

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This paper considers a method to identify the parameters for the piezoelectric shunt damping. Employing the self-sensing actuator methodology, the proposed method uses the piezoelectric element for shunt damping as a sensor/actuator, and only a simple circuit is required for the experimental setup. From the frequency response obtained from the voltage signals of the circuit, the parameters are calculated simply by the linear least squares method. The experimental results demonstrate the efficiency of the proposed method.

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In this paper, we proposed new parameter identification technique using orthogonal functions to identify the density and the modulus of elasticity of each segment of the beam. Using orthogonal functions, we could consider the parameter distribution in idientification and identified the distribution of the density and the modulus of elasticity with a few parameters. We applied the Haar series for the cracked beam and the Fourier series and Legendre series for the uniform and the combined beam. We checked the applicability of our technique for the parameter identification by the simulation and found the considerable reduction of the calculation time and good regularization ability.

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Locomotion, one of the most basic robotic functions, has been widely studied for several types of robots. As for self-reconfigurable modular robots, there are two types of locomotion; one type is realized as a series of self-reconfiguration and the other is realized as a whole body motion such as walking and crawling. Even for the latter type of locomotion, designing control method is more difficult than ordinary robots. This is because the module configuration has many degrees of freedom and there are a wide variety of possible configurations. We propose an offline method to generate a locomotion pattern automatically for a modular robot in an arbitrary configuration, which utilizes a neural oscillator as a controller of the joint motor and evolutionary computation method for optimization of the neural oscillator network, which determines the performance of locomotion. We confirm the validity of the method by software simulation and hardware experiments.

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This paper introduces elliptic Gabor wavelets with the triangular lattice configuration as a model-based target recognition approach. And, making the degree of overlap uniform between the neighboring Gabor wavelets in the frequency domain, it enables to cover the frequency space with higher density than the existing circular Gabor wavelets with square lattice configuration. Thus, it succeeds efficiently to extract a rotation and scale invariant features of the target objects. This paper, furthermore, presents some useful guidelines for designing system parameter values by a large amount of experiments, and shows effectiveness of the proposed method by comparing it with other methods.

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The self-powered active vibration control system, which produces control force using energy regenerated by dampers is applied to rubber-tired vehicle suspensions. Such systems do not require external energy to produce control force. The proposed system is composed of an electric actuator, a condenser, relay switches and a variable resistor. To discuss its feasibility, the balance between the regenerated and the consumed energy is examined and the conditions under which regenerated energy is greater than consumed energy are obtained. Then control schemes of the self-powered system are presented and their performance are examined through numerical simulations. The results indicate that the system achieves active vibration control without external energy and its performance is as good as a typical active controller using external energy.

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This paper deals with a control method of rotary cranes with rotating and boom-hoisting operations. The control systems should have robustness with respect to rope length, mass of load and frictional disturbances, which are variant parameters in the rotating and the boom-hoisting motions. Firstly we derive a simple linear model of the crane dynamics by using a disturbance observer. The model has robustness with respect to the mass of load and the frictional disturbances. Although dynamics of the rotary crane are described by a double-input quadruple-output nonlinear system, the derived linear dynamics are two single-input double-output systems, so that we can easily design the robust control system with respect to the rope length. In the control system, by using nominal natural frequencies of rope-load vibration system, desired closed-loop poles are easily assigned without trial and error. We further propose a method of adding an integrator to the controller for reducing positional errors of the crane. The effectiveness of the proposed method is experimentally confirmed by comparisons with conventional controllers.

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This study examined a function of the low speed adaptive cruise control system (low speed ACC). The effect of the difference of the low speed ACC with and without stop control functions on driver behavior was investigated in the driving simulator experiment. The effect of the difference of low speed ACC functions on the reduction effect of driving workload was also estimated from actual vehicle data in traffic congestion. In case of the ACC without stop control, excessively dependent for the system was not observed. The driver positively carried out the braking operation, and the possibility of a preceding vehicle collision comparatively lowered as the result. On the other hand, the reduction effect of driving workload by the ACC with stop control was remarkably estimated high regardless of the traffic environment.

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Conventional structural optimization methods are difficult to apply to the early process of design referred to as conceptual design, in which diverse design solutions are to be obtained. This paper describes a design method that obtains diverse design solutions. As a first step, a form-generation system that generates diverse forms is proposed. In this case, the diversity of organism is noted, and the form-generation method is referred to 'induction' and 'apical dominance' in the developmental process of organism. The proposed system, consisting of a generation process and an optimization process, is applied to the structural design of chairs, and the diversity of solutions is analyzed. As a result, it is shown that, as compared with conventional structural optimization methods, the proposed method obtains design solutions of adequate diversity. The results indicate the effectiveness of the proposed system for obtaining diverse design solutions.

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This study uses experimental and computational analysis to investigate the dynamic behavior of a fly line. Fly-casting is one of the most significant issues in fly-fishing. In order to cast a lightweight fly, the weight of a fly line is utilized. Fling speed, the casting process and the loop shape of the line while in flight are important for the proper presentation of flies. Moreover, the shape of a fly line is also important for a long cast or controlled cast. In this paper, the fly-casting process is investigated experimentally in the case of wrist fixed.

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This study uses experimental and computational analysis to investigate the dynamic behavior of a fly line. Fly-casting is one of the most significant issues in fly-fishing. In order to cast a lightweight fly, the weight of a fly line is utilized. Fling speed, the casting process and the loop shape of the line while in flight are important for the proper presentation of flies. Moreover, the shape of a fly line is also important for a long cast or controlled cast. In this paper, a rod and a line are modelled and calculated in the case of wrist fixed.

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In the engineering domain, the specialization of engineering knowledge is growing with the advancement of technology, and the area which one disigner handles is narrowing. However expertise in a wider area is needed to achieve practical design, therefore multiple designers need to cooperate on the disign of any one product. This process is called design collaboration. The aim of collaboration is to achieve complex, large-scale disign by the sharing of knowledge and information amongst several designers. In recent years, customer requirements are more sophisticated, so companies need to develop advanced products to maintain their market share. As a result, it has become more important to achieve a creative design. The second aim of collaboration is to achieve this creative design. This paper discusses an advanced collaborative system to support a creative design process that depends on interactive communication among a number of designers. The new system presented in this paper enables the flow of more creative ideas from the process of interactive communication among a number of designers.

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In NC machining of noncircular contours, where cutter is fed along a straight line intersecting perpendicularly the roration axis of work piece, the cutter path usually consists of Archimedes's spiral segments. From machining precision and efficiency point of view, a desired cutter path should be composed of the fewer segments as possible under the condition of satisfying the specified interpolation error limitation. In this paper, an optimal interpolation principle of Archimedes's spiral for planar curves is presented and then a practical algorithm is constructed. The segment number of the cutter path resulted from the algorithm not only is the fewest but also the interpolation accuracy agrees with the specified value. It is also evidenced that the profile error of machined contour corresponding to the cutter path is perfectly controlled within the desired value, i. e. the specified interpolation error value, through detailed analyses. The interpolation results of using the presented algorithm for machining disc cam profile are compared with those obtained by Nishioka's methods ⁽³⁾ . The comparison results sufficiently confirm the validity of the algorithm developed by the authors.

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Virtual Enterprise (VE) is a temporary alliance of enterprises that come together in order to better respond to cope with demand of customers. VE includes many kinds of business models in term of supply chain, such as vertical structure, horizontal structure and so on. In this study, we focus on the negotiation process in VE, and try to apply multi-agent paradigm with marketing science and game theoretic approach as its decision making mechanism in order to analyse the characteristics of several business models. We propose VE simulation models to analyse the forming dynamism of VE amongst several potential members in the negotiation domain, and finally clarify the performance of VE based business models.

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Recently, in the field of machine tool, measuring instrument, robot, medical industry, information processing and so on, many miniature structures are used for high precision or many functions. When machine structure becomes small, the influence of the surface area becomes larger than that of the volume. For example, in the case of the micro-machine, mass of the machine becomes small in proportion to the cube, but surface area of the machine only becomes small in proportion to the square, and frictional force or air resistance which are very influenced by surface area become the factor of the unstable behavior. Therefore, the control of the coefficient of friction between the sliding parts is an important factor for stable behavior of the machine. And standard deviation of coefficient of friction was also an important factor. In this study, relationships between specifications of the sliding surface of a minute part and the coefficient of friction or its standard deviation were investigated in experiment. Photo-fabrication for final treatment on the sliding surface were used. At first, relationship between friction and some environment conditions was investigated. Then relationship between friction and specifications of sliding surface was measured. In addition, a neural network for designing specifications of sliding surface with the desired coefficient of friction was builded up and evaluated. It is concluded from the results that (1) Coefficient of friction was changed only 0.03 by some environment conditions, (2) Relationship between the specifications of the sliding surface and the coefficient of friction was declared, (3) The sliding surface with the desired coefficient of friction was designed by inverse analysis using neural network.

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To clarify the wear resistance and seizure resistance of the vegetable oils with anti-wear additives of Dibenzyl-Disulfide (DBDS) and Phosphonic Acid-Dibutyl (DBPo), the four-ball tests were carried out under dip-feed lubrication using Soda-type four-ball machine. The width of the wear scar on the stationary balls lubricated with the vegetable oils containing DBPo additive was smaller than that without the additive, and was smaller than that containing DBDS additive. The seizure resistance of the vegetable oils with DBDS additive increased in following order : Turbine oil<Rapeseed oil<Soybean oil<Corn oil. On the other hand, the seizure resistance of the vegetable oils with DBPo additive increased in the following order : Turbine oil<Soybean oil<Corn oil<Rapeseed oil. The DBPo additive showed significant improvements in seizure resistance compared with DBDS additive.

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An elastic robot finger has been developed for controlling grasping force when weight and frictional coefficient of grasped object are unknown. First, geometry of the finger is designed. The elastic finger has ridges at the surface to divide the contact area. Geometry of the ridges is trapezoid like human ridges. It also has a pair of tactile sensors embedded per one ridge similar to human fingertips. The surface of the whole finger is curved so that normal reaction force distributes unequally. A Finite Element (FE) model of the elastic finger was made to conduct a dynamic contact analysis using a FE method in order to design the elastic finger in detail. Then the elastic finger was made to confirm the results of FE analyses. At a result, it was confirmed by calculation and experiment that the elastic finger can detect the incipient slippage of the ridge that occurs near the edge of contact area and can deduce the stick area ratio. This result in useful for controlling grasping force when the weight and friction coefficient between the elastic finger and grasping object are unknown.

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A path of contact of gears for power transmission in this series of papers is assumed to be designed under the following design conditions that it has (1) A constant gear ratio under a given disposition of two axes, (2) No variation of bearing loads which means that it is a straight line coinciding with the contact normal, (3) A pair of smooth tooth surfaces around the design point, (4) A pair of teeth with contact ratio required and (5) Equal strengths of bearing and tooth on both drive and coast sides. This second paper clarifies that a path of contact under the design conditions (1) and (2) is expressed by 5 unknown variables which are determined by giving the design point and the inclination angle of the path of contact in this designing method and as the result, they include 3 independent variables for bevel and hypoid gears and 2 for crossed helical, worm and cylindrical gears, which will be chosen to satisfy other conditions (3), (4) and (5).

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In this paper curvatures of skew gears are investigated and not only interference but bload items about curvature are discussed. First, expressions of free direction curvature on the tooth surface of gears are derived by two direction curvatures on the tooth surface of gear 1. Second, space image and expressions and characteristics of many items about curvature are clarified. Finally, the method of space display of curvature are shown and examples of curvature space image of involute worm gears are shown. A feature of this paper is the new viewpoint from the expressions of free direction curvature derived by two direction curvatures of gears 1. The new viewpoint give possibility to discuss more broad and detailed space image and characteristics. For example, the theory of minimum relative curvature is clarified. It is known that small relative curvature is good to performance about wear.

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Polishing processes of silicon wafers have been traditionally carried out utilizing colloidal silica slurry on a polishing pad. It causes the bad working environment and the high total polishing cost. A pad with fixed ultrafine silica has been developed to solve these problems. However, it still has the problem of too low removal rate as a polishing pad. In this study, a new fixed-abrasive tool which applies aggregate silica grains and adds alkaline powders into the pad is developed. Instead of conventional abrasive slurry, a slurry-free polishing could be performed by only supplying D. I.-water. The experiments have been carried out on silicon wafers. As a result, compared with the traditional slurry process, higher removal rate and better finishing roughness could be obtained. Moreover, it could be possible to obtain the constant supply of alkaline and the constant polishing rate by coating of alkaline powders.

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This study deals with on-machine resharpening of cutting tools for the purpose of reducing the consumption of scarce materials and suppressing the total production time on precision machining. To make the resharpening processes on machine automatically, the processes must he fast and its apparatus must be simple. So the conventional methods like grinding or PVD coating can't meet the requirements. Electrodeposition of composite coating is one of the methods which meet the requirements. Ni-P-SiC composite coating layer on cemented carbide tool was able to cut steel. Then, by electrolytic etching with H₂SO₄ electrolyte, Ni-P-SiC on cemented carbide is removed at the rate of 20μm/min or faster and the oxidative reaction stops by itself result from that cemented carbide forms passive state layer. Using these coating and stripping methods, resharpening process takes within only 5 minutes.

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Recently, a demand of miniaturization and performance enhancement of the printed wiring board is intensified more and more with the rapid populaization of the information terminal electronic equipment. The processing by the drill is generally used in small diameter drilling of the printed wiring board. Then, the through-hole of small diameter is desired for the miniaturization of the equipment. And, there is the internal damage of drilled hole in one of the problems in the formation of the through-hole in the drilling. Therefore, it is necessary to consider internal damage that causes the migration and plating to decrease with the reliability of the product. Then, it is required that the deterioration of the drilled hole quality is controled. Therefore, for the purpose of clarifying. the factor that affects the damage, width and thickness of fiber bundle of glass cloth used as a reinforcement of the GFRP were noticed in this study. And, internal damage and effect of the thrust force and cutting torque were examined using those 5 kinds of different materials. Following conclusions were obtained : (1) To make smaller the influence of the damage width by the rotation angle and to do high reliability drilling, it is effective to equal the rate of fiber bundle of each warp yarn and weft yarn occupied in each direction. (2) The approximation of the damage width was deduced from feed rate and fiber bundle thickness, and it is possible that damage width with the glass cloth of various fiber bundle thickness is estimated.

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The effect of the cutting fluids on the machinability of Al-Cu-Si alloys which is candidate of the free cutting aluminum alloys without lead have been studied. The turning test was carried out using the cutting tool with the chip breaker. It was found that surface roughness after machining of the alloys became roughened, while the generation of the adhesion on the cutting tool was increased either in the dry or the wet cutting conditions. In the dry cutting, the chip breaking was better in the over aged alloys where the adhesion was easily generated. On the other hand, the chip breaking in the wet cutting was better in the under aged alloys where the adhesion was hard to generate. These results can be explained in terms of generation of the adhesion on the cutting tools ; in the dry cutting, the chip was greatly bent by the existence of the adhesion on the cutting edge of the cutting tool though, in the wet cutting, the chip breaker acted effectively by the adhesion was not easily generated.

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