Journal of Advanced Mechanical Design, Systems, and Manufacturing
Online ISSN : 1881-3054
ISSN-L : 1881-3054
7 巻 , 2 号
選択された号の論文の16件中1~16を表示しています
Technical Note
Papers
  • Shigeru NAGASAWA, Yuki KOMIYAMA, Pusit MITSOMWANG
    2013 年 7 巻 2 号 p. 103-114
    発行日: 2013年
    公開日: 2013/03/01
    ジャーナル フリー
    This paper describes about the intensity of stress concentration, and the maximum stress component occurred on the inside liner of a corrugated fiberboard during a rotary creasing process. Three dimensional finite-element analysis, based on the combination of orthotropic-elastic liners and Ring Crush Test based medium, was carried out by varying mechanical conditions such as the working diameter of the main-creaser, the boundary constraint of lateral tensile state and the misalignment of the biting position with an apex of corrugated medium. The simulated stress distribution and deformation shape of inside liner explained about a few experimental features, such as the failure occurrences on the inside liner.
  • Ryutaro TANAKA, Shuhei YAMAZAKI, Akira HOSOKAWA, Tatsuaki FURUMOTO, Ta ...
    2013 年 7 巻 2 号 p. 115-124
    発行日: 2013年
    公開日: 2013/03/01
    ジャーナル フリー
    This paper proposes a method for measuring the tool edge temperature during tapping. The infrared ray from the tool edge of the tapping tool was measured using a two-color pyrometer with an optical fiber. In addition, the vibration caused by contact between the first-act tool edge and the workpiece was sensed by an acceleration pickup. The outputs of the pyrometer from the tool edges and chips could be distinguished by analyzing the cutting behavior in the tapping process. The tool edge temperature was successfully measured for tapping of AISI 1045-based free-machining steel and stainless steels. The cross-sectional cutting area appears to control the tool edge temperature. The maximum tool edge temperatures with thee two steels at a cutting speed of 30 m/min reached almost 300 and 400°C, respectively. The cutting torque for stainless steel 303 was 3.4 N·m lower than when tapping stainless steel 304. The tool edge temperature for stainless steel 304 reached the maximum value of 510°C. The temperature for stainless steel 303 was about 100°C lower than of stainless steel 304.The tool edge temperature for stainless steel 304increased linearly with the cutting speed. The rate of increase in the tool edge temperature with increase in cutting speed from 25 m/min to 30 min was larger than that from 20m/min to 25min. Therefore, the tool edge surroundings apparently became harder with an increase of cutting speed.
  • Jun OKAMOTO, Yu KUMASAKA, Kazuya KAWAMURA, Tomoyuki MATSUMOTO, Seiji K ...
    2013 年 7 巻 2 号 p. 125-139
    発行日: 2013年
    公開日: 2013/03/01
    ジャーナル フリー
    We have been developing the Orthopaedic physical examination assisting system using magnetic position tracker to quantitate knee laxity diagnosis. In this study, to investigate the influence of anatomical landmark sampling error for bone coordinate registration, reproducibility verification simulation was done. Firstly, the motion data of imitation bones was acquired using the system and set as a reference data. To get the error motion data, virtual error vectors were added on the reference sampling points and new motion data was recomputed. Evaluation was executed by comparison with the reference data and recomputed data. The evaluation results lead improvement methods of measurement reproducibility as follows. 1. It is important to point the landmarks proximal to the knee carefully because the contribution of the motion error is higher than the distal landmarks. 2. To reduce the registration error, thigh and shank receivers should be set close to the knee as possible. 3. If the allowance area of the sampling error is in 2.0 mm diameter circle, Diagnosis error using IKDC Knee examination form is approximately 20 %.
  • Jungchul KANG, Masaharu KOMORI
    2013 年 7 巻 2 号 p. 140-155
    発行日: 2013年
    公開日: 2013/03/01
    ジャーナル フリー
    Geared transmissions are used in a variety of mechanical devices to realize a wide range of speeds or torques. However, the transmission of power and motion in a geared transmission is interrupted when the working gear pairs are changed to vary the velocity ratio. In order to solve this problem, an uninterrupted transmission system was proposed in the previous report that can change the velocity ratio while transmitting power and rotation from the input shaft to the output shaft. However, in the uninterrupted transmission system, there are some cases in which it is difficult to design a suitable noncircular gear based on the combination of angular velocity ratios. In addition, since there is a design constraint that must be satisfied between the angular velocity ratio and the number of teeth on the clutch, the gears and clutches cannot be designed independently. To solve this problem, a new type of uninterrupted transmission system that enables the design of a suitable noncircular gear for various combinations of angular velocity ratios is proposed in this report. Furthermore, in order to avoid the constraint between the angular velocity ratio and the number of teeth on the clutch, a new transition method is proposed. An experimental device using the novel uninterrupted transmission system is constructed, and the effectiveness of the proposed system is verified by experiment.
  • Yuan KANG, Sheng-Yen HU, Sheng-Chuan CHEN, Yeon-Pun CHANG
    2013 年 7 巻 2 号 p. 156-170
    発行日: 2013年
    公開日: 2013/03/01
    ジャーナル フリー
    Constant flow valves have been presented in industrial applications or academic studies, which compensate recess pressures of a hydrostatic bearing to resist load fluctuating. The flow rate of a constant-flow valve can be constant in spite of the pressure changing in a recess. However the design parameters of this type valve must be specified. This paper analyzes the dynamic responses of the spool-type constant-flow valve that is designed as a spool-type restrictor but with matched preloading spring and supply pressure. In this study the static analysis presents the specific relationships among design parameters for constant flow rate and the dynamic analyses give the variations around the constant flow rate as the working pressure fluctuates.
  • Hideaki ONOZUKA, Koji UTSUMI, Tomu KATO, Hayato TAKAHASHI, Toshiyuki O ...
    2013 年 7 巻 2 号 p. 171-186
    発行日: 2013年
    公開日: 2013/03/01
    ジャーナル フリー
    Aiming to suppress chatter vibration during machining of huge mechanical parts, dies, and molds, a design method for a damped arbor imbedded with a mass damper was devised. First, an analysis method coupled with Rayleigh's method was developed and used to calculate the stiffness of an arbor with a tapered hollow space for installing the mass damper inside. In the formulation of the vibrating system with two degrees of freedom, the displacement ratio is introduced for accurate calculation of the counter force of the damper mass. Then, the shape and size of the hollow space was optimized in order to maximize the negative real part of the compliance of the arbor. The proposed design method can increase the dynamic stiffness of the damped arbor with a hollow with the minimum reduction in its static stiffness. Furthermore, it is found that once the damper is optimized for the maximum length of an arbor in a certain design range, it can be applied to a shorter arbor without deterioration of dynamic stiffness. Finally, chatter noise and machined surface roughness measured experimentally proved that a damped arbor prototyped by the proposed design method has much higher cutting performance than a conventional one.
Technical Note
Papers
  • Yu WANG, Li LIN
    2013 年 7 巻 2 号 p. 195-204
    発行日: 2013年
    公開日: 2013/03/12
    ジャーナル フリー
    This paper proposes a novel method for evaluating the braking system on oil rig. The Evaluation indexes, braking capacity, response speed control accuracy and braking efficiency, are put forward according to the drilling safety, benefit, quality and so on. The experimental apparatus to the performances of brakes was built by measuring the relation between the braking pressure, torque and rotation speed. The performances of pneumatic disc brake, hydraulic disc brake and pneumatic band brake are researched by modeling, theoretical analysis and experiment. Based on quantitative analysis, the value analysis is used to quantitatively and qualitatively evaluate the indexes. Some suggestions were put forward for selecting the braking system according to the evaluation. The total evaluation standard system is first proposed and it avails to optimize and evaluate the braking system on oil rig and its automation. Traditional selective method based on experience can be revised and the conclusions also provide a new reference for researching the automation of braking system and other mechanical systems.
  • Chin-Nan CHEN, Chin-Hsi LIAO, Yunn-Shiuan LIAO
    2013 年 7 巻 2 号 p. 205-218
    発行日: 2013年
    公開日: 2013/03/19
    ジャーナル フリー
    Thread cutting is one of the crucial machining procedures of mechanical processing. However, breakage of the nose of a threading tool is relatively common in fine-thread machining and directly related to the nose radius. The design concept of the unequal nose radius (UNR(1)) tool involves increasing the radii of the front teeth of a multi-point threading tool and maintaining the radius of the last tooth as the nose radius of the standard thread. This design can enhance the machining efficiency and remove burr. However, no method exists for determining the nose radius. Ideally, each tooth of a UNR multi-point threading tool should have approximately the same life span. Because the life of the tool is inversely proportional to the strain value, we proposed comparing the maximum strain value of each tooth to determine the nose radii. A recursive binary search was adopted for comparison. The best values were then gradually converged into a single solution to obtain the optimal nose radii combination. Considering a 3-point threading tool for example, the recursion results provided the optimal radii combination. The experiments confirmed that the machining efficiency of the 3-point threading tool was 15 times of that of a single-point threading tool.
  • Mohebullah WALI, Shinji WAKUI
    2013 年 7 巻 2 号 p. 219-232
    発行日: 2013年
    公開日: 2013/03/19
    ジャーナル フリー
    In this paper, a unidirectional positioning stage which is supported by four coil-type spring isolators and actuated by four pneumatic cylinders is considered. The stage jerk feedback scheme (SJFB) with positive polarity is proposed to reduce the stage mass, resulting in the improvement of positioning speed. However, reduction of stage mass results in the overshoot that can be controlled by increasing the stage stiffness through the outer feedback loop controller. In addition, to avoid the self-oscillation of stage caused by high gain of SJFB and to improve the repeatability, the conventionally used scheme, namely, base plate jerk feedback (BPJFB) with positive polarity based on its damping role is combined with the SJFB scheme. It is concluded from the experimental results that the proposed control system obeys the related theory and provides high speed positioning with improved repeatability. The amount of the reduced mass through SJFB scheme is also experimentally estimated.
  • Yoshiyuki KARUNO, Kazushi TAKAHASHI, Atsushi YAMADA
    2013 年 7 巻 2 号 p. 233-243
    発行日: 2013年
    公開日: 2013/03/29
    ジャーナル フリー
    The lexicographic bi-criteria combinatorial food packing problem to be discussed in this paper is described as follows. Given a set I = {i | i = 1, 2, . . . , n} of current n items (for example, n green peppers) with their weights wi and priorities γi, the problem asks to find a subset I' (⊆ I) so that the total weight ΣiI' wi is no less than a specified target weight T for each package, and it is minimized as the primary objective, and further the total priority ΣiI' γi is maximized as the second objective. The problem has been known to be NP-hard, while it can be solved exactly in O(nT) time if all the input data are assumed to be integral. In this paper, we design a heuristic algorithm for the problem by applying a data rounding technique to an O(nT) time dynamic programming procedure. We also conduct numerical experiments to examine the empirical performance such as execution time and solution quality.
  • Mohd Sanusi ABDUL AZIZ, Tatsuaki FURUMOTO, Kazuhiro KURIYAMA, Shigeki ...
    2013 年 7 巻 2 号 p. 244-256
    発行日: 2013年
    公開日: 2013/04/05
    ジャーナル フリー
    This study investigates the residual stress and deformation induced in a consolidated structure obtained through a layered manufacturing process. In this research, temperature and dynamic stress induced in the substrate during a selective laser melting (SLM) process were measured to investigate the influence of laser irradiation conditions on the development of residual stress and deformation in the consolidated structure. The stress was measured using a strain gauge that was attached on the bottom face of the substrate, whereas the temperature was measured using a thermocouple inserted in the substrate. The influences of the substrate height, consolidated structure height, and laser scanning pattern on the deformation and residual stress also were investigated experimentally. Additionally, the effects of different materials used as the substrate on deformation were investigated. It was found that during the laser consolidation process, temperature changes in the substrate caused repeated thermal expansion and shrinkage within the substrate, producing internal stress at the completion of the laser consolidation process. The stress that was induced in the substrate corresponds to the deformation result. Residual stress at the top of the consolidated structure increased whereas residual stress at the bottom of substrate decreased as the height of the consolidated structure increased. However, less deformation occurred when using stainless steel as the substrate.
  • Jeongju CHOI
    2013 年 7 巻 2 号 p. 257-267
    発行日: 2013年
    公開日: 2013/04/05
    ジャーナル フリー
    This paper presents the robust tracking control of EHA (Electro Hydrostatic Actuator) system. EHA system provides the simple structure and frees from the environment pollution, but the poor tracking performance is caused by the internal leakage, surging of pump and friction. In order to increase the tracking performance of EHA system, ABSC (Adaptive Back-Stepping Control) with RBFNN (Radial Basis Function Neural Networks) is proposed. The proposed control scheme can guarantee the robustness and increase the tracking performance in accordance with the external disturbance and unmodeled uncertainties. The update law for the proposed ABSC with RBFNN is designed based on the reconstruction error. To verify the effectiveness of the proposed control scheme, computer simulation and experiments are executed and the results were compared with that of the general BSC(Back-Stepping Control).
  • Xingsheng LI, Tetsusei KURASHIKI, Masao FUKUDA
    2013 年 7 巻 2 号 p. 268-281
    発行日: 2013年
    公開日: 2013/04/16
    ジャーナル フリー
    Diaphragms made of stainless steel plates are widely used in switching parts in electrical devices, which control on/off of the electric supply of electric devices. However, there are many geometrical parameters for designing diaphragms such as height, diameter, and so on. The aim of the study is to estimate effects of the design parameters on click characteristics of diaphragms based on FEM. In the numerical analysis, the residual stress generated in the press forming has been investigated, and the click characteristics such as load and click ratio were estimated with the numerical model by changing the geometry of several diaphragms. Finally, the relationship between design parameter and click characteristics was defined as ‘design space’, and we could obtain the designable area by controlling the design parameters. Furthermore, if the diameter of a diaphragm was changed, we could choose the diaphragm by controlling the design parameters based on the proposed designable area. From these results, the proposed design space is useful for the estimation of the designable region of diaphragm considering click characteristics.
  • Ming-Fu LIN, Kao-Hua CHANG
    2013 年 7 巻 2 号 p. 282-294
    発行日: 2013年
    公開日: 2013/04/24
    ジャーナル フリー
    Continuing improvements in computer and machine tool technology have led to many new and fascinating applications in CAD/CAM systems. One of the most fruitful areas of CNC machine research is kinematic analysis, which describes the mapping between the set of cutter position and orientation and the set of joint variables. There has thus far been relatively little research into the mapping between the set of joint variables of machine tool and set of joint variables of another machine tool. In this thesis we develop a method called machine coordinate values exchange (MCVE) model, which aims to deal with this kind of analysis. This proposed methodology is a mathematical form, applicable to both academic research and production, and enables the direct and rapid generation of joint variables. This study also presents a novel graph, called an isometric schematic, to conceptualize the prototype of multi-axis machine, and establishes and shows the feasibility of the MCVE model for two different types of machine tools.
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