Journal of Advanced Mechanical Design, Systems, and Manufacturing
Online ISSN : 1881-3054
ISSN-L : 1881-3054
2 巻 , 4 号
Special Issue on Advanced Manufacturing Technology
選択された号の論文の39件中1~39を表示しています
Special Issue on Advanced Manufacturing Technology
Papers
  • Keiichi NAKAMOTO, Mitsuru TSUNODA, Keiichi SHIRASE, Toshimichi MORIWAK ...
    2008 年 2 巻 4 号 p. 464-473
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    In 3+2-axis control milling, it is difficult to determine effective tool posture automatically. In this study, a rapid acquisition method of material removal volume is proposed for process planning. Material removal volume is an important factor to determine effective tool posture for realizing high efficient milling. In the proposed method, workpiece shape, product shape and tooling shape are represented by using the voxel representation for calculating the discrete cross correlation function. The offset surface is generated on the boundary of the existence of the similarity between product shape and tooling shape. Tooling swept area is calculated as the convolution of the tooling shape. Consequently, material removal volume and unmachined volume are obtained based on product shape, workpiece shape and tooling swept area. The computation load of the acquisition method is independent of the complexity of the product shape, tooling shape and tool posture. The respective removal volume in different tool posture can be simply evaluated. The effectiveness of the removal volume acquisition method is confirmed in conducted case studies.
  • -Application of Non-Circle Cutting-
    Yoshitaka MORIMOTO, Yoshio ICHIDA, Ryunosuke SATO, Yukio OHORI
    2008 年 2 巻 4 号 p. 474-481
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    A new cutting device driven by an enlargement mechanism with a PZT drive has been developed to realize positioning the cutting tool from nm to mm. In this study, the mechanical principal of a newly developed enlargement mechanism consisting of fluid chamber, a PZT device, and cutting tool stage is reported. The basic performances of the developed mechanism are also evaluated. This developed device demonstrates that the magnitude of enlargement reaches 4 times of stroke than the original one of the PZT. The dynamic characteristics show DC to 50 Hz which is enough frequency response to realize the non-circle cutting. The non-circle profile is machined by the developed mechanism. The profile accuracy obtained settles in ±1.3μm by the repetitive control method.
  • Keisuke UMEZAWA, Yasuhiro KAKINUMA, Seiichiro KATSURA, Kohei OHNISHI, ...
    2008 年 2 巻 4 号 p. 482-492
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    The linear motor driving mechanism has been adopted as a positioning mechanism of machine tools to realize high speed and precise positioning because of friction-free and no backlash. However, when two or more linear motors are used, minute differences between the thrust forces of each motor causes the generation of micro vibration and the change of velocity of each linear motor generated by yawing around the center of gravity. This study proposes interaction-mode-control method for the machine tool table driven by three linear motors to control the three modes defined as the position of the center of gravity, bending and yawing independently. The interaction-mode-control method is a new technique for applying interaction modes defined according to the workspace to the real control system through modal conversion. From the results of simulation and experiments, it is confirmed that the three modes are controlled independently and, therefore, bending and yawing can be suppressed using interaction-mode-control. Moreover, to combine the interaction-mode-control method with disturbance observer and feedforward control, this control system has high robustness and precise positioning can be realized.
  • Xiaoyou ZHANG, Tadahiko SHINSHI, Akira SHIMOKOHBE, Tatsushi SATO, Hide ...
    2008 年 2 巻 4 号 p. 493-503
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    The objective of this study is to realize high-speed electrical discharge machining (EDM) using a wide-bandwidth, high-precision, millimeter-stroke, 5-DOF controlled maglev local actuator. In this paper, we report on the EDM of 1mm diameter holes using the maglev local actuator, and discuss the relationships between machining speed, the bandwidth of the actuator and the control gain of the EDM system. The experimental results show that the machining speed using the maglev local actuator was improved as the bandwidth of the actuator and control gains of the EDM system increased.
  • Hiroshi MATSUDA, Hiroyuki SASAHARA, Masaaki FUKUDA, Masaomi TSUTSUMI
    2008 年 2 巻 4 号 p. 504-512
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    A textural surface pattern is used to add a physical or decorative function to an object's surface. We have proposed a milling technique involving patch division that can quickly generate a geometric surface pattern using a common profile-forming method. This report describes a method of generating a tool path using 3D-CAD and an FEA preprocessor applied to the patch division milling of a curved surface. Experimental results of the proposed method as applied to spherical and free-form surfaces are described.
  • Hiroyasu IWABE, Hideki MIWA
    2008 年 2 巻 4 号 p. 513-521
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    This paper deals with the cutting mechanism and cutting performance by ball end milling of curved surface. Firstly, the modeling of a cutter and a workpiece with a concave curved surface are carried out using 3D-CAD. Secondly, the chip area is calculated by the interference of the rake surface and the chip volume removed by a single cutting operation. The maximum chip area shows transitional phenomenon, then a new cutting method such as a looped cutter path machining is proposed and the effectiveness of the new method is considered and verified using the evaluation value which is calculated by the multiplication of the chip and the length from Z axis to the gravity of the chip area.
  • Erween Abd. RAHIM, Kamaruddin KAMDANI, Safian SHARIF
    2008 年 2 巻 4 号 p. 522-531
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    This paper presents the experimental investigation into the performance of the uncoated carbide tool when high speed drilling (HSD) of Ti6Al4V. Machining responses such as thrust force, torque, vibration, chip formation and surface integrity of drilled surface were evaluated at various cutting conditions. Results show that cutting speed and feed significantly influenced the above responses. Folded wavy type chips and curly type chips were produced under all tested cutting conditions. It was also found that the transition from aperiodic to periodic chip formation occurred as the cutting speed increases. In addition, improvement of the drilling performance was also recorded as a result of reduction of acceleration amplitude during peck drilling method was adopted. Observation on the subsurface of the drilled workpiece indicates a severe plastic deformation at all tested cutting conditions.
  • Hiroshi NAKAJIMA, Atsushi KATO, Hiroyuki SASAHARA, Hiromasa YAMAMOTO, ...
    2008 年 2 巻 4 号 p. 532-539
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    In this report, a driven rotary tool's machining performance on SUS304 stainless steel was examined. The rotary tool was attached to a milling axis on a multi-tasking lathe which has B axis control. It is possible to adjust the tool's circumferential speed as the tool is controlled to rotate by a milling motor. As well, the contact angle between the work-piece and cutting point are controllable as the milling axis has four degrees of freedom of movement. The objective of this study is to clarify the influence of tool posture on the rotary cutting process. It was found that the tool temperature increase and also the chip flow angle increases, when the tool inclination angle increases.
  • Etsuji OHMURA, Masayoshi KUMAGAI, Makoto NAKANO, Koji KUNO, Kenshi FUK ...
    2008 年 2 巻 4 号 p. 540-549
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    In this study, “stealth dicing” (SD) was applied to ultra thin wafers 50 μm in thickness. A coupling problem composed of focused laser propagation in single crystal silicon, along with laser absorption, temperature rise and heat conduction was analyzed by considering the temperature dependence of the absorption coefficient. When the depth of the focal plane is too shallow, the laser is also absorbed at the surface as the thermal shock wave reaches the surface. As a result, not only is an internal modified layer generated but ablation occurs at the surface as well. When the laser is focused at the surface, strong ablation occurs. Ablation at the surface is unfavorable because of the debris pollution and thermal effect on the device domain. It was concluded that there is a suitable depth for the focal plane so that the thermal shock wave propagates inside the wafer only. The optimum irradiating conditions such as pulse energy, pulse width, spot radius, and depth of focal plane can be estimated theoretically also for ultra thin wafer.
  • Keiji OGAWA, Toshiki HIROGAKI, Eiichi AOYAMA, Hajime IMAMURA
    2008 年 2 巻 4 号 p. 550-559
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    Recently, materials made of natural resources have been gaining attention. In particular, high expectations are placed on bamboo fiber. However, conventional bamboo fiber extraction techniques have problems, primarily involving quality, accuracy, and efficiency. To solve these problems, a new method of obtaining bamboo fibers with a machining center (MC) is proposed. NC programs are designed according to a cutting theory based on a geometrical tool path for cylindrical work. The experimental results verify that fiber shape can be controlled by adjusting the appropriate end-milling conditions with a spiral tool path. The fiber length is influenced by the axial depth of the cut, while the fiber diameter is influenced by the vascular bundle size, which is a component of bamboo. Therefore, considering the direction and size of the bamboo components, the desired bamboo fibers can be obtained with high quality and accuracy using end-milling with an MC.
  • Yasuhiro KAKINUMA, Nobuhito YASUDA, Tojiro AOYAMA
    2008 年 2 巻 4 号 p. 560-569
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    Polydimethylsiloxane (PDMS) is one of the important materials for microfluidic chips. The pattern of micro channels on the PDMS plate is usually fabricated through the photolithography and micro molding process. However, the photolithographic method requires multi chemical and mechanical processes and resultant long process time. The micro milling process is a feasible method for rapid fabrication of various patterns of micro channels. However, micromachining has not yet been applied to soft polymer materials. It is difficult to machine elastic materials such as PDMS because of their low toughness. In order to machine a micro grooves on soft polymer materials, the cutting process applying cryogenic cooling is proposed because the elastic properties of soft polymer materials remarkably change from rubbery state to glassy state below the glass transition temperature. In this study, the freezing milling method using liquid nitrogen is applied to the micro grooving of PDMS. The result of a cutting test shows that micro grooves can be shaped easily and machined accurately in PDMS by the proposed method.
  • Masakazu FUJIMOTO, Yoshio ICHIDA, Ryunosuke SATO
    2008 年 2 巻 4 号 p. 570-578
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    To clarify the wheel wear characteristics in grinding process using vitrified cBN wheels, we have investigated the change in wheel wear behavior when the load on the grain cutting edge is increased by increasing work speed. Wheel wear behavior in the grinding process may be classified into two main types, a) wheel wear process-type 1, that is consists of initial and steady-state wheel wear regions, and b) wheel wear process-type 2, that is consists of initial, steady-state and abnormal wheel wear regions. In the steady-state wear region of wheel wear process-type 1, lower wheel wear rate, lower stable grinding forces and good finished surface roughness are obtained, because self-sharpening due to micro fractures of the cutting edges takes place. In grinding with wheel wear process-type 2, it is very hard to obtain good finished surface and high grinding ratio, because of occurrences of fracture or releasing of cBN grains.
  • Suryadiwansa HARUN, Toshiroh SHIBASAKA, Toshimichi MORIWAKI
    2008 年 2 巻 4 号 p. 579-586
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    In this paper, turning with actively driven rotary tool method was investigated. The main purpose of the present work is to examine influences of machining conditions especially the tool rotational speed and direction upon the cutting force components, the chip formation and the cutting temperature. Experimental results show that cutting temperature decreases with an increase in the tool rotational speed in a certain speed range. The change in tangential force against the tool rotational speed is not so large than radial and axial force. Increase in the tool rotation in CCW direction exited chatter due to the large radial force.
  • Pai-Shan PA
    2008 年 2 巻 4 号 p. 587-596
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    A new mechanism design using a magnetic force with high efficiency to assist discharging dregs out of the electrode gap during the electrochemical finishing on the surface finish process that follows end-turning is investigated in the current study. Through simple equipment attachment, magnetic-assistance during electrochemical finishing can follow the cutting process on the same machine. This process can be used for various end-turning operations. Among the factors affecting electrochemical finishing, the magnetic-assistance is primarily discussed. The experimental parameters are chemical composition and concentration of the electrolyte, flow rate of the electrolyte, initial gap width, current rating, on/off period of pulsed current, feed rate of workpiece, rotational speed of workpiece and electrode, magnetic strength, and distance between the two magnets. A higher current rating with magnetic-assistance reduces the finishing time and avoids the difficulty of dreg discharge. Providing a large magnetic field intensity or using a small distance between the two magnets produces a larger magnetic force and discharge ability and better finishing. A large rotational speed of the workpiece and electrode produces better finishing. Pulsed direct current can slightly promote the effect of electrochemical finishing, but the current rating needs to be increased. The magnetic-assistance during the electrochemical finishing process makes a great contribution in a short time by making the surface of the workpiece smooth and bright.
  • Takuya MATSUDA, Fumiki TANAKA, Masahiko ONOSATO, Hiroaki DATE
    2008 年 2 巻 4 号 p. 597-608
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    In a machining system using computer numerical control (CNC) machine tools, detailed models of machining information are necessary to simulate detailed machining and to control the complex motion of machine tools. However, existing machining information models lack the necessary information and are described in their own formats. Consequently, many models which include the same information exist. Moreover various simulations for a virtual machining system and adaptive control for a real machining system are inacculate. To solve these problems, a digital machining information (DMI) model to support a real-virtual machining system is proposed in this study.
  • Takashi MATSUMURA, Yasuaki MIYAHARA, Takenori ONO
    2008 年 2 巻 4 号 p. 609-618
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    The dynamic response in the cutting operations with the small diameter tools is measured to simulate the cutting process in micro-scale milling. The inclined ball end mills are excited with measuring the exciting force on the vibration generator. Then, the compliance of the tool-spindle system is measured with changing the excitation frequency. The modal parameters are estimated with changing the cutter axis inclination and the overhang of the tool. A vibration model is presented to show that the vibration is subjected in the radial direction of the small diameter tool. A dynamic cutting process is simulated to show the effect of the spindle speed on the tool displacement based on the estimated modal parameters.
  • Katsuhiro OTA, Atsushi TSUTSUMI
    2008 年 2 巻 4 号 p. 619-628
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    A novel supercritical cleaning process was proposed for removing contamination in high aspect ratio trenches and microholes of highly integrated semiconductor devices. The supercritical CO2-pulse cleaning with the periodic pressure swing of supercritical fluid between subcritical and supercritical conditions was conducted for removing particles in microholes of fabricated model structures. The microhole depth is 2.0 μm with microhole sizes ranging from 0.2 μm to 1.6 μm. The effects of microhole size on particle removal were investigated by means of non-destructive observation of high aspect ratio model structures with an optical microscope and SEM. The supercritical CO2-pulse cleaning efficiently removed more than 50 nm fine particles from the deep microholes owing to its drastic changes in density near the critical point by depressurization of the supercritical fluid.
  • Koei MATSUKAWA, Katsunori SATOH, Akihiro GOTO, Nagao SAITO, Naotake MO ...
    2008 年 2 巻 4 号 p. 629-639
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    Recently hard layers have tried to be formed using electrical discharge machines (EDMs) which are mainly used now for material removal. The time and cost of producing dies and machine parts can be greatly reduced when the same EDM is used as the main plant machine in die making and surface modification. The wear properties of hard layers formed on stainless steel using EDM were studied. As a result, it was found that surface layers modified with both titanium hydride (TiH2) green-compact electrodes and titanium carbide (TiC) semi-sintered electrodes had a hardness of about 2,600 HV, and a surface roughness of 10 to 13 μmRy. And the coating thickness of a surface layer modified with a TiH2 electrode was 12 μm, but the coating thickness of a surface layer modified with a TiC electrode was thinner at 2 μm. However the hard layers formed with TiH2 electrodes were three to four times more wear resistant and the layers formed with TiC electrodes were about ten times more wear resistant than surfaces without a hard layer.
  • Yoshio ICHIDA, Ryunosuke SATO, Masakazu FUJIMOTO, Hiromichi TANAKA
    2008 年 2 巻 4 号 p. 640-650
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    This paper deals with a fractal analysis of the wear behavior of the grain cutting edges in superabrasive grinding. Fundamental overcut fly grinding experiments for producing individual straight grooves using a grinding tool with multiple grits are carried out to clarify the wear characteristics of the grain cutting edges in the grinding process and then the change in three-dimensional profile of the cutting edge measured with a multiprobe SEM is evaluated on the basis of fractal analysis. The main results are summarized as follows: (1) Fractal dimension for the contour line of the fine cutting edge formed by micro fracture shows a higher value than that of cutting edge formed by attritious wear or large fracture. (2) Fractal dimension for cBN grain cutting edge mainly formed by micro fracture tends to take a higher value than that for diamond grain cutting edge mainly formed by attritious wear. (3) The complex change in shape of the cutting edge with the progress of grinding process can be quantitatively evaluated by means of fractal analysis.
  • Yasuhiro OKAMOTO, Ryoji KITADA, Yoshiyuki UNO, Hiroyuki DOI
    2008 年 2 巻 4 号 p. 651-660
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    This paper deals with the effects of the nozzle shape on cutting results and fundamental characteristics of laser cutting of solid type molded composite materials, which was composed of semiconductor board and epoxy-resin molding compounds, by Q-switched single-mode fiber laser. Experimental results clarified that high speed cutting of 16 mm/s could be carried out using a Laval throat nozzle with initial expansion zone, which also led to straighter kerf shape and narrower kerf width than other nozzles. Besides, Laval throat nozzle made it possible to reduce the kerf width, and the difference of kerf width between irradiation-side and exit-side became smaller. Nitrogen assist gas led to the narrow kerf width and straight kerf shape. Furthermore, the difference of kerf between substrate side and epoxy-resin side became smaller. Substrate side irradiation was more suitable for precision cutting than epoxy-resin side irradiation. These results proved that Q-switched single-mode fiber laser was useful for cutting of composite materials.
  • Yasuhiro OKAMOTO, Tomokazu SAKAGAWA, Hikaru NAKAMURA, Yoshiyuki UNO
    2008 年 2 巻 4 号 p. 661-667
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    Aluminum nitride and silicon carbide are expected as a useful material for the substrate in semiconductor industry because of their excellent properties. Precision micro-machining without crack and with little heat affected zone is required for their applications. Shorter wavelength makes it possible to remove a material with little heat affected zone because of its high photon energy. Therefore, effects of wavelength on machining characteristics of AlN and SiC in micro-drilling using Q-swithched YAG harmonics were experimentally investigated. The drilled depth increased with decreasing the wavelength. Under the reduced pressure condition, the drilled depth increased, and the better surface integrity could be obtained compared to the atmospheric pressure condition. The circumference region around the drilled hole was oxidized for all the case, and the oxidization in the case of fourth harmonic was more remarkable than that in second harmonic. In the initial stage of drilling for AlN with fundamental wavelength, the irradiated point expanded by the absorption of laser beam with increasing the number of laser pulse, and the processing was carried out by crumbling the grain due to the thermal expansion. On the other hand, the higher harmonics could make a hole at the irradiated point from the initial stage without thermal expansion.
  • Koji TERAMOTO, Jun'ichi KANEKO, Tohru ISHIDA, Yoshimi TAKEUCHI
    2008 年 2 巻 4 号 p. 668-674
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    This paper presents a framework of a compositional machining simulation. Because the machining process involves complex physical phenomena, various fragmented process simulations, such as cutting force, thermal behavior, vibration, and so on, have been investigated. The authors have proposed a concept of the compositional machining simulation which enables a versatile machining simulation. The concept is based on the building block type construction of the various machining process simulators. An association framework and systematic description of fragmental process models are explained. As an example of the framework, fragmented simulations of endmilling process are organized as a multi-aspect simulation.
  • Satoshi KANEKO, Ryuta SATO, Masaomi TSUTSUMI
    2008 年 2 巻 4 号 p. 675-684
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    This paper proposes a mathematical model of a feed drive system consisting of a cylindrical linear motor and linear ball guides. The friction model consists of two components; a model for the relationships between displacement and friction force under microscopic motion (non-linear spring characteristic), and a model for the relationship between velocity and friction force (Stribeck curve). The non-linear spring is modeled from the results of very low frequency simple harmonic motion experiments. The Stribeck curve is modeled from the results of friction force experiments conducted for various constant velocities. The parameters in the model were derived from machine specifications of the feed drive system and experimental results. In addition, in order to account for the quantization error of the linear scale, the controller and amplifier were modeled as a discrete time system. To evaluate the proposed model, step responses and circular motion under various conditions were measured and simulated. The influence of the friction characteristics on dynamic behavior was then investigated. In the experiment, the friction characteristics were changed and compared using three greases with differing viscosities. As a result, it was confirmed that differences in grease viscosity strongly influence the damping of vibrations for the step responses. Furthermore, it was clarified that quadrant glitches do not appear in the microscopic displacement region. For many simulation results, it was verified that the proposed model accurately reflects the real behavior.
  • Ryunosuke SATO, Yoshio ICHIDA, Yoshitaka MORIMOTO, Kenji SHIMIZU
    2008 年 2 巻 4 号 p. 685-693
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    The purpose of this study is to make clear the polishing characteristics of the manganese oxide slurry for wire material of Cu. To examine the polishing characteristics of the manganese oxide slurry, a series of polishing experiments for oxygen free copper have been carried out by using MnO2, Mn2O3 and Al2O3 as abrasive grains and polishing properties have been discussed. As a result, the best result among three kinds of slurries is obtained in polishing with Mn2O3 slurry at the viewpoints of the stock removal and surface roughness. Furthermore polished surfaces have been analyzed using SEM and atomic force microscope. While a large number of mechanical scratches are observed in the polished surface with Al2O3 slurry, the polished surfaces with manganese oxide slurries are covered with fine protrusions. It seems that the fine protrusions result from interaction between mechanical and chemical effects.
  • Akira OKADA, Yoshiyuki UNO, Atsuo IIO, Kunihiko FUJIWARA, Kenji DOI
    2008 年 2 巻 4 号 p. 694-700
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    A new surface modification for bio-titanium alloy products by electron beam (EB) polishing is proposed. In this EB polishing method, high energy density EB can be irradiated without concentrating the beam. Therefore, large-area EB with a maximum diameter of 60mm can be used for instantaneously melting or evaporating metal surface. Experimental results made it clear that surface characteristics, such as repellency, corrosion resistance and coefficient of friction could be improved simultaneously with the surface smoothing in a few minutes under a proper condition. Therefore, EB polishing method has a possibility of high efficient surface smoothing and surface modification process for bio-titanium alloy.
  • Yasuhiro UENISHI, Toshiki HIROGAKI, Eiichi AOYAMA, Takahiro IIDA, Masa ...
    2008 年 2 巻 4 号 p. 701-710
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    We propose a non-contact method using infrared ray thermography for measuring gear tooth contact to focus attention on the heat generated on the tooth surface at meshing. First, the radiation performance of the gear tooth surface and the effect of lubrication oil were investigated. Then, the reliability of this technique was evaluated by comparing with the observation result of tooth contact with red lead which is traditional red paint for industrial use. Finally, the possibility of evaluating the meshing transmission error was shown. The results show this technique is effective for monitoring the contact pattern and confirming the surface pressure.
  • Ryuji IWASHITA, Hiroyuki SASAHARA
    2008 年 2 巻 4 号 p. 711-718
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    For the planarization process of LSI wafers, metal bumps covered with a certain kind of resin are machined with a diamond tool before its stacking. In this study, the deformation process and temperature field in this process are analytically simulated with FEM. In order to analyze the cutting process for resin which has a viscosity, the cutting simulator first has to treat the visco-elastic-plastic material property. Secondly, to analyze the cutting at the micro-meter level depth of cut, the analysis model was scaled down. Finally, to simulate the cutting process of a LSI wafer, PVC and 70%Cu-30%Zn brass were assigned a resin and a metal part, respectively. As a result, it was clarified that the machining temperature during a resin cutting remains high even if the depth of cut is a micro-meter scale because of its poor thermal conductivity. In addition, the chip forming process showed very discriminative deformation at the boundary between the metal bump and a resin.
  • Hossein TEHRANI NIK NEJAD, Nobuhiro SUGIMURA, Koji IWAMURA, Yoshitaka ...
    2008 年 2 巻 4 号 p. 719-734
    発行日: 2008年
    公開日: 2008/07/31
    ジャーナル フリー
    Process planning and scheduling are important manufacturing planning activities which deal with resource utilization and time span of manufacturing operations. The process plans and the schedules generated in the planning phase shall be modified in the execution phase due to the disturbances in the manufacturing systems. This paper deals with a multi-agent architecture of an integrated and dynamic system for process planning and scheduling for multi jobs. A negotiation protocol is discussed, in this paper, to generate the process plans and the schedules of the manufacturing resources and the individual jobs, dynamically and incrementally, based on the alternative manufacturing processes. The alternative manufacturing processes are presented by the process plan networks discussed in the previous paper, and the suitable process plans and schedules are searched and generated to cope with both the dynamic status and the disturbances of the manufacturing systems. We initiatively combine the heuristic search algorithms of the process plan networks with the negotiation protocols, in order to generate suitable process plans and schedules in the dynamic manufacturing environment. A simulation software has been developed to carry out case studies, aimed at verifying the performance of the proposed multi-agent architecture.
  • Akira OKADA, Toshiyuki YAMAUCHI, Kimihiko ARIZONO, Yoshiyuki UNO
    2008 年 2 巻 4 号 p. 735-741
    発行日: 2008年
    公開日: 2008/08/12
    ジャーナル フリー
    The purpose of this study is to develop a new type of wire electrode, in which piano wire with very high tensile strength is coated with electrically conductive layer, such as brass or zinc, in order to attain high speed and high precision wire EDM. In this report, using a trial-made thin wire of 50μm in diameter, the optimum thickness and quality of brass layer were experimentally investigated for higher performance fine wire EDM. Furthermore, the influence of the tensile strength of piano wire used as a core wire was discussed. As a result, the coated brass with copper content of 60-70% is effective and the thickness of coated brass is needed to be more than 1.45μm for high removal rate.
  • Fusaomi NAGATA, Tetsuo HASE, Zenku HAGA, Masaaki OMOTO, Keigo WATANABE
    2008 年 2 巻 4 号 p. 742-752
    発行日: 2008年
    公開日: 2008/08/12
    ジャーナル フリー
    Control of robotic mold polishing is considered in this paper. CAD/CAM-based position/force controller that simultaneously performs stable force control and exact pick feed control along curved surface is presented for articulated-type industrial robots. The force feedback loop controls the polishing force consisting of the contact force and the kinetic friction force. During mold polishing, the position feedback loop has a delicate contribution to the force feedback loop in Cartesian space so that the abrasive tool does not deviate from the desired trajectory but keeps a constant pick feed. When a mold polishing robot runs, cutter location (CL) data with normal vectors are used for not only a desired trajectory of tool translational motion but also desired contact directions given to a mold. The CL data allow the robot to realize a complete non-taught operation of the position and the contact direction. In this paper, a simple experiment is conducted by using an industrial robot with a ball-end abrasive tool in order to evaluate the effectiveness of the proposed method. The target workpiece is an aluminum PET bottle blow mold after NC machining, whose curved surface has small cusp marks with each pick feed of about 0.3 mm height. The results show that the proposed mold polishing robot with the CAD/CAM-based position/force controller can uniformly remove the cusp marks and further achieve mirror-like surface quality without undesirable over-polishing.
  • Tatsuhiko SAKAGUCHI, Toshihide KAMIMURA, Keiichi SHIRASE
    2008 年 2 巻 4 号 p. 753-761
    発行日: 2008年
    公開日: 2008/08/12
    ジャーナル フリー
    Unexpected disruptions often occur in the manufacturing systems. The manufacturing systems cannot execute the manufacturing operations in accordance with the predetermined production schedule due to such disruptions. Therefore, a systematic scheduling method is required to cope with such disruptions. In this research, distribution of processing time is described with the normal distribution. The reactive scheduling method for distribution of processing time is proposed in order to modify the predetermined production schedule. And the suitable re-scheduling period is considered through the computational experiments.
  • Masayuki TANAKA, Yasuhiro KAKINUMA, Tojiro AOYAMA, Hidenobu ANZAI, Tak ...
    2008 年 2 巻 4 号 p. 762-772
    発行日: 2008年
    公開日: 2008/08/19
    ジャーナル フリー
    Semiconductor process technology increasingly requires high accuracy and efficiency. In the case of processing thin fragile substrate such as silicon wafer, it has to be fixed with low strain. In addition, its fixture device can be used under vacuum condition because some processes are carried out in vacuum. It is required to develop a new fixture device for vacuum transportation of silicon wafer. ERG is the functional material whose friction characteristic varies according to the intensity of applied electric field. The surface friction of ERG can be changed quickly and reversibly applying the electric field. In other words, it becomes easy to fix and release a substrate by control of electric field. In this study, ERG is applied to a fixture element of silicon wafer available for vacuum process. The ERG fixture element was trial-manufactured and its performance under vacuum condition was evaluated experimentally. The result shows that the ERG effect emerges in vacuum and ERG can fix silicon wafer sufficiently. Moreover, numerical analysis of electric filed was carried out to obtain the optimal pattern of the one-sided electrodes used for the ERG fixture element. It is clear that the optimal width of electrodes exists according to the gap of electrodes and the thickness of ERG.
  • Daisuke ARUGA, Arata KANEKO, Nobuyuki MORONUKI
    2008 年 2 巻 4 号 p. 773-782
    発行日: 2008年
    公開日: 2008/08/19
    ジャーナル フリー
    This paper discusses the design of surface microstructures for quick drying. The structures produced in this study were arrays of micropillars with different sizes and pitches fabricated by photolithography. It was found that the sliding angle decreased with an increase in the pitch of the pillars. Hence, droplets could be removed easily. However, the evaporation time increased significantly. To achieve a balance between the evaporation time and the sliding angle, a reticular pattern consisting of pillars and flat areas was designed and tested. The evaporaiotn time became shorter than the fully arrayed surface on this pattern, while the sliding angle could not be made small. The evaporation time became shorter than the fully arrayed surface on this pattern, while the sliding angle could not be made small.
  • Yoshihito KANAMORI, Arata KANEKO, Nobuyuki MORONUKI, Takafumi KUBO
    2008 年 2 巻 4 号 p. 783-791
    発行日: 2008年
    公開日: 2008/08/19
    ジャーナル フリー
    This study demonstrates the application of dip coating to self-assembly of fine particles on a substrate that is covered with line-and-space pattern of hydrophilic (SiO2) and hydrophobic materials (OTS). The pattern was fabricated on a substrate by lithography first. The substrates were drawn up from the water-based suspension in which particles were dispersed and the particles self-assembled on the hydrophilic region only forming the packed-structure. Then, contact printing was applied for the patterning to extend the scale. The scale was extended up to 10mm x 10mm while keeping the self-assemble performance.
  • Go ABE, Masatoshi ARITOSHI, Tomoki TOMITA, Keiichi SHIRASE
    2008 年 2 巻 4 号 p. 792-799
    発行日: 2008年
    公開日: 2008/08/22
    ジャーナル フリー
    Recently, a demand for precision machining of dies and molds with complex shapes has been increasing. Although CNC machine tools are utilized widely for machining, still machining error compensation is required to meet the increasing demand of machining accuracy. However, the machining error compensation is an operation which takes huge amount of skill, time and cost. This paper deals with a new method of the machining error compensation. The 3D surface data of the machined part is modified according to the machining error measured by CMM (Coordinate Measuring Machine). A compensated NC program is generated from the modified 3D surface data for the machining error compensation.
  • Seksan CHAIJIT, Shigeru NAGASAWA, Yasushi FUKUZAWA, Mitsuhiro MURAYAMA ...
    2008 年 2 巻 4 号 p. 800-811
    発行日: 2008年
    公開日: 2008/08/26
    ジャーナル フリー
    This paper reports for the cutting mechanism of a thin worksheet on a flexible underlay by wedge indentation. The effect of underlay's rigidity on the cutting characteristics and separation limit of aluminum foil is studied. Indentation of a 42 degree center bevel blade into a 10μm thickness aluminum foil mounted on several flexible underlays was carried out experimentally and numerically. For discussing the effect of the underlay yield stress and Young's modulus on the deformation behavior of worksheet, an elasto-plastic finite element analysis was carried out. The followings were obtained: (i) the deformation features of the worksheet on a flexible underlay is classified into three patterns: the hard, the mixture, and the floating mode; (ii) there are upper bound rigidities and the lower bound rigidities of the floating phenomenon; (iii) the floating phenomenon is evidenced when the rigidities of underlay are less than the lower bound rigidities; (iv) the mixture mode enables to cut off a worksheet using a bending elongation effect on the outer surface of worksheet.
  • Jiang ZHU, Ryo SUZUKI, Tomohisa TANAKA, Yoshio SAITO
    2008 年 2 巻 4 号 p. 812-823
    発行日: 2008年
    公開日: 2008/08/27
    ジャーナル フリー
    In this paper, a surface sculpturing system based on 8-axis robot is proposed, the CAD/CAM software and tool path generation algorithm for this sculpturing system are presented. The 8-axis robot is composed of a 6-axis manipulator and a 2-axis worktable, it carves block of polystyrene foams by heated cutting tools. Multi-DOF (Degree of Freedom) robot benefits from the faster fashion than traditional RP (Rapid Prototyping) methods and more flexibility than CNC machining. With its flexibility driven from an 8-axis configuration, as well as efficient custom-developed software for rough cutting and finish cutting, this surface sculpturing system can carve sculptured surface accurately and efficiently.
  • Akira KAKUTA, Yuji FURUKAWA, Nobuyuki MORONUKI
    2008 年 2 巻 4 号 p. 824-832
    発行日: 2008年
    公開日: 2008/08/29
    ジャーナル フリー
    Silicon carbide is expected to be used as a next-generation material because of its more effective mechanical and electronic properties. The hetero Molecular Beam Epitaxy process may provide a method to form thin layered mono-crystal Silicon carbide on a Silicon substrate. The present paper aims to clarify the relation between the layer's properties and the substrate crystal orientations, especially (100) and (110), and discusses the mechanism of Silicon carbide growth under certain operating conditions through a series of tests and evaluations.
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