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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal of The Korean Society of Manufacturing Technology Engineers
Journal Basic Information
Journal DOI :
The Korean Society of Manufacturing Technology Engineers
Editor in Chief :
Volume & Issues
Volume 22, Issue 6 - Dec 2013
Volume 22, Issue 5 - Oct 2013
Volume 22, Issue 4 - Aug 2013
Volume 22, Issue 3 - Jun 2013
Volume 22, Issue 3_1spc - Jun 2013
Volume 22, Issue 2 - Apr 2013
Volume 22, Issue 1 - Feb 2013
Selecting the target year
A Study on Concentrating Photovoltaic Module with Plate Structure
Park, Seung-Jae ; Hong, Min-Sung ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 629~634
DOI : 10.7735/ksmte.2013.22.4.629
This study aims to investigate a new structure for a concentrating photovoltaic (PV) module using a III-V compound semiconductor solar cellto solve the problems of existing concentrating PV modules and to explore a concentrating optical system with a flat structure, which shows remarkable advantages in terms of manufacturing cost, installation, and maintenance. This study should greatly contribute toward the development of concentrating PV modules. This study was performed to achieve an improvement in efficiency and economy and to implement an actual product. A new source of renewable energy is the only way in which countries that cannot produce oil can even emerge as an energy power. Therefore, this work can serve as a fundamental study that will help South Korea grow into a country that is a PV power generation force.
Development of the Air Floating Conveyor System for the Large Glass Sheet
Lee, Tae Geol ; Yu, Jin Sik ; Jung, Hyo Jae ; Kim, Jong-Hyeong ; Kim, Joon Hyun ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 635~642
DOI : 10.7735/ksmte.2013.22.4.635
We have prepared a DEMO conveyor device for conveying a large 8G class glass sheet using ahorizontal air-cushion system. This device consists of the body frame and the driving frame that are combined to realize a frame for conveying glass without any contact.The driving frame comprises an air flotation table (bed), drive roller supported at both ends, and ASU. Part of the ASU serves to control the airflow as the chamber consists of a porous pad and fan. Fiber filters replace the porous pad and axial fans serve as an air compressor. In addition, to determine the appropriate glass levitation from the air table, this study examined the design specifications of the applied filter (discharge speed of HEPA and ULPA filters, and flow rate) as well as the height of the and the proper supporting roller height (14mm). Then, after adjusting the position of the ASU and the number of ASUs required to configure the UNIT air floating C/V, we analyzed the height and flatness of the glass and derived the appropriate layout (1140-mm distance between ASUs).
Study on Implant Cleaning Effect of Lasers of Different Wavelengths
Park, Eun Kyeong ; Yang, Yun Seok ; Lee, Ka Ram ; Yoo, Young Tae ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 643~651
DOI : 10.7735/ksmte.2013.22.4.643
This study applied a laser cleaning method (dry cleaning) that is used for cleaning semiconductor elements to dental implant cleaning. The lasers used in this study were pulsed fiber lasers with wavelengths of 1,064 and 532 nm. The peak output, energy per pulse, energy density per pulse, time of pulse experiment, and number of pulse experiments served as process variables for this study, and the variables were changed for each experiment. As a result, a laser with a wavelength of 532 nm showed much higher cleaning efficiency than its 1,064 nm counterpart. As the wavelength range decreased, the quantized energy increased and the reflection rate of the titanium used for the implant decreased; consequently, the energy absorption rate increased. Therefore, it is proposed that the energy density by wavelength has a greater influence on cleaning than does the output size.
Study on Development of Automation System for Non-Contact Counting of ID Card
Kang, Dae-Hwa ; Hong, Jun-Hee ; Guo, Yang-Yang ; Lee, Hyok-Won ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 652~657
DOI : 10.7735/ksmte.2013.22.4.652
In this study, we developed a counting method for non-contact ID cards using an optical fiber displacement sensor instead of the traditionally used friction counting method. The proposed method has the advantage of high speed and automated measurement. For counting non-contact ID cards, an H-type optical fiber sensor, jig part, and counting program are developed separately to build the system and adjust it. Through the experimental test results, it was confirmed that counting is possible with one type of international ID card and one type of financial security card based on ISO7810. Furthermore, by applying the proposed method to 100 ID cards 100 times repeatedly, it was confirmed that it has high accuracy and an error ratio of 0%. We experimentally demonstrated that the proposed counting method for non-contact ID cards using an optical fiber displacement sensor can perform measurements with high accuracy and high speed.
Study of Active Damping Boring Bar Using Piezoelectric Actuator for Small Boring Process
Guo, Yang-Yang ; Hong, Jun-Hee ; Song, Doo-Sang ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 658~664
DOI : 10.7735/ksmte.2013.22.4.658
In this paper, we present a case study of vibration suppression based on the application of active damping to the small boring process of a boring bar with diameter below
. The proposed active damping system consists of an acceleration sensor for real-time monitoring of the vibration signal, a driver for phase control in a computer program, and piezoelectric actuators for damping. In this system, the vibration signals are detected by the acceleration sensor and sent to the computer as an input. The phase shift parameter of the natural frequency of the input signal is sent to the data acquisition board in the computer and calculated by the phase control program. This study confirmed the effectiveness of this damping system, and it opens up the possibility of the development of active damping systems for small boring processes.
The Porosity Control Technology of Lap Joint Welding Using Continuous Wave Nd:YAG Laser of the Low Carbon Steel SS41
Lee, Ka Ram ; Hwang, Chan Youn ; Yang, Yun Seok ; Park, Eun Kyeong ; Yoo, Young Tae ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 665~672
DOI : 10.7735/ksmte.2013.22.4.665
With the development of advanced processing technology, laser processing systems, which require high-quality precision processing, have attracted considerable attention. Although laser equipment is expensive, it enables quick processing and less deformation of materials. This technology is often applied to secondary batteries, which has thus farinvolved the use of argon tungsten inert gas (TIG) welding. However, the welding characteristics of argon TIG welding are not yet good, and a laser is used for welding to address this problem. In this study, lap-joint welding was conducted, and the desired welding characteristics were obtained when the laser power was 1800W and the laser beam travel speed was 1.8 m/min. Lap-joint welding was conducted on Ni-coated SS41. Two cases were compared. No pores were observed in the Ni-coated SS41 lap-joint welding part, and cracks appeared from the lap-joints. Moreover, the pole rod and tap were welded together in a T-joint form to improve the output of the secondary battery. T-joint laser welding showed better welding characteristics than TIG welding.
Study on Strength Durability of Automotive Front Bumper during Driving
Han, Moon-Sik ; Cho, Jaeung ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 673~679
DOI : 10.7735/ksmte.2013.22.4.673
This study investigates the strength durability of an automotive front bumper subjected to vibrations during driving. Through structural analyses,the maximum equivalent stresses of models 1 and 2 were found to be 187.09 and 278.4 MPa, respectively. The maximum deformations of models 1 and 2 were 1.3772 and 2.675 mm, respectively. As model 1 shows less deformation than model 2, itis stronger than model 2. Models 1and 2 show natural frequencies within 230 Hz as the range of the maximum harmonic response frequency. Models 1 and 2 have maximum amplitude displacements of 0.105 and 0.154 mm at critical frequencies of 159 and 110 Hz, respectively. As model 1 has a higher critical frequency than model 2, it has more strength durability than model 2. This study result can be effectively utilized for the design of a front bumper by investigating prevention against damage and its strength durability.
Modeling of a Confinement Effect in Laser Shock Peening on Titanium Alloy
Lee, Wooram ; Kim, Joohan ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 680~685
DOI : 10.7735/ksmte.2013.22.4.680
In this study, the effect of laser shock peening on a titanium alloy was modeled using different confinements. Both liquid and solid confinement could be applied to laser shock peening, and solid confinement provided a dry laser shock peening process, which has the advantage of a corrosion-free effect. When a different confinement was applied to laser shock peening, a different peening effect would be expected. In our study, the peening effect was numerically modeled and simulated. The main effect of different confinements was a change in the impedances required to confine a shock wave from a plasma. The impedances were assumed with respect to different materials. Johnson-Cook`s plastic deformation modeling was applied to the simulation. The strains and residual stresses were calculated to evaluate the confinement effects. When solid confinement was used, the residual stress increased by 60-85%, compared to the case of liquid confinement. However, the depth of the residual stress was slightly deeper. The simulated results could be applied to estimate the peening effect when a different confinement was used in the laser shock peening process.
Measurement of Aluminum Liner Internal Defect Deformation and Strain Using Shearography and FEM Verification
Choi, In-Young ; Hong, Kyung-Min ; Ko, Kwang-Su ; Kang, Young-June ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 686~692
DOI : 10.7735/ksmte.2013.22.4.686
Today, environmental issues have become a matter of worldwide concern. In particular, automobile industries engage in considerable research and investment to develop high-efficiency and ecofriendly cars. Most ecofriendly cars use natural gas or hydrogen gas instead of fossil fuels. In this regard, low-weight and high-pressure vessels have gradually been developed to increase the driving distance of a car. However, most pressure vessels installed in cars develop many defects over time owing to shocks sustained when the car is being driven. Such defects can cause the explosion of the pressure vessel. Therefore it is important to prevent such explosions due to internal defects. The use of shearography for measuring the internal defects of objects afford many advantages. It is a non-contact and non-destructive method, and it is not limited by the object shape. In this study, the internal defect deformation and strain of an aluminum liner that is used in a CNG bus for the fuel storage tank is measured using shearography. It is important to measure the strain and deformation in order to detect defects and repair the pressure vessel. To verify the accuracy of the shearography measurement method, the measurement results of shearography, out-of-plane ESPI, and FEM are compared quantitatively.
Analysis on Life Prediction for Different Materials in Vehicle Door Hinge Lightweight Design
Yu, Ki Hyun ; Kim, Hong Gun ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 693~699
DOI : 10.7735/ksmte.2013.22.4.693
Environmental issues are attracting increasing interest worldwide, and accordingly, environmental regulations for vehicles are being made more stringent. As a result, the car industry is conducting studies focusing on fuel efficiency and lightweight vehicles. To manufacture lightweight vehicles, existing steel parts are replaced by composite materials and lightweight metals. In this study, the fatigue life of a new material for manufacturing lightweight car door hinges was predicted using a finite-element analysis program. The existing steel material was replaced by carbon-fiber-reinforced plastic (CFRP) and aluminum alloy 6061, and the test results were analyzed. The maximum stress decreased by approximately three times, whereas the fatigue life and safety factor increased. When only CFRP was used, its allowable stress, safety factor, and fatigue life were excellent, but the sagging of the product exceeded the allowable value, which posed a limitation in use. Therefore, it seems desirable to use an appropriate combination of steel, AA6061, and CFRP for this product.
Development of the Two-piece Aluminum Wheels Using the Friction Stir Welding
Choi, In-Young ; Kang, Young-June ; Kim, Andrey ; Ahn, Kyu-Saeng ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 700~707
DOI : 10.7735/ksmte.2013.22.4.700
Owing to high oil prices and environmental issues, the automobile industry has conducted considerable research and made large investments to manufacture a high-efficiency automobiles. In the case of automobile wheels in which a lightweight material is used to increase the fuel efficiency a mold is used to increase the production efficiency; however, the use of the molding method for this purpose is very expensive. Therefore an automobile wheel consists of two parts. In this study a two-piece automobile wheel is manufactured by the friction stir welding(FSW) of Al6061-T6 to reduce the manufacturing cost and process complexity. The FSW welding tool geometry and rotational speed, and the feed rate are key factors that significantly affect the weld strength. Therefore tensile tests were conducted on specimens produced using various welding conditions, and the optimal FSW welding conditions were applied to manufacture aluminum wheels. To ensure reliability, prototype aluminum wheels were manufactured and their mechanical reliability and safety were evaluated using a durability test, fatigue durability test, and impact test. Through this study, aluminum wheel production was made possible using the FSW method.
A Study on the Characteristics of Vibration Due to the Forces of Drive Shaft
Sa, Jongsung ; Kang, Taewon ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 708~716
DOI : 10.7735/ksmte.2013.22.4.708
This study aims to understand the applied forces and related vibrational characteristics of a tripod joint (TJ), which is mostly used in front-drive-type middle-sized sedans in South Korea. The plunging force (PF) and generated axial force (GAF) are the most influential quantities related to the vibrational characteristics of a driveshaft. To obtain meaningful data, specially designed tests were performed using MTS test sets. The results of direct measurements reveal that higher PF and GAF values appear to worsen the vibrational characteristics of the vehicle. On the other hand, the measured apparent mass is useful for calculating the applied forces for a short driveshaft that has no dynamic vibration absorber. Among diversely controlled samples, it shows that the viscosity and tight fit are very sensitive to shudder vibrations of the vehicle. Therefore, these are good design factors for quality controls in the production line of constant-velocity joints.
Design of Ultrasonic Tool Horn for Wire Wedge Bonding
Lee, Bong-Gu ; Oh, Myung-Seok ; Ma, Jeong-Beom ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 717~722
DOI : 10.7735/ksmte.2013.22.4.717
In this study, we investigated the design of a wire wedge bonding ultrasonic tool horn using finite element method (FEM) simulations. The proposed method is based on an initial design estimate obtained by FEM analysis. An ultrasonic excitation causes various vibrations of a transducer horn and capillary. A simulated ultrasonic transducer horn and resonator are then built and characterized experimentally using a laser interferometer and electrical impedance analyzer. The vibration characteristics and resonance frequencies close to the exciting frequency are identified using ANSYS. FEM analysis is developed to predict the resonance frequency of the ultrasonic horn and use it in the optimal design of an ultrasonic horn mode shape.
Identification and Reduction Method for Refrigerator Contraction and Expansion Noise
Kim, Wonjin ; Park, Seong Kyu ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 723~729
DOI : 10.7735/ksmte.2013.22.4.723
The contraction and expansion noise of a refrigerator are investigated, and some effective methods are proposed to reduce the level and occurrence frequency of noise. First, the noise of a refrigerator is measured to estimate the frequency spectrum and occurrence frequency of noise. Second, a sound visualization was conducted using an acoustic camera to determine the location of the noise source. From the results, it was observed that the internal part mainly producing noise was the third shelf in the freezer room. A method to estimate the acceleration on the location of the noise source is introduced to analyze the contraction and expansion noise precisely and accommodate experimental convenience. Noise reduction methods such as the replacement of the existing shelf with glass shelves, adoption of rail slides, and increase of roughness on the contact surface of the shelf are proposed and tested.
Integrated Dynamic Simulation of a Magnetic Bearing Stage and Control Design
Kim, Byung-Sub ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 730~734
DOI : 10.7735/ksmte.2013.22.4.730
The dynamic simulation of machine tools and motion control systems has been widely used for optimization, design verification, control design, etc. There are three main streams in dynamic simulation: structural dynamic analysis based onthe finite element method, dynamic motion analysis based on equations of motion, and control system analysis based on transfer functions. Generally, one of these dynamic simulation methods is chosen and employed for specific purposes. In this study, an integrated dynamic simulation is introduced, in which the structure, motion, and control dynamics are combined together. Commercially well-known software is used in the integrated dynamic simulation: ANSYS, ADAMS, and Matlab/Simulink. Using the integrated dynamic simulation, the dynamics of a magnetic bearing stage is analyzed and the causes of oscillation and noise are identified. A controller design for suppressing a flexible dynamic mode is carried out and verified through the integrated dynamic simulation.
Rotating Accuracy Analysis for Spindle with Angular Contact Ball Bearings
Hwang, Jooho ; Kim, Jung-Hwan ; Shim, Jongyoup ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 735~739
DOI : 10.7735/ksmte.2013.22.4.735
The error motion of a machine tool spindle directly affects the surface errors of machined parts. Spindle motion errors such as three translational motions and two rotational motions are undesirable. These are usually due to the imperfectness of bearings, stiffness of spindle, assembly errors, and external force or unbalance of rotors. The error motions of the spindle need to be reduced for achieving the desired performance. Therefore, the level of error motion needs to be estimated during the design and assembly process of the spindle. In this study, an estimation method for five degree-of-freedom (5 DOF) error motions for a spindle with an angular contact ball bearing is suggested. To estimate the error motions of the spindle, the waviness of the inner-race of bearings and an external force model were used as input data. The estimation model considers the geometric relationship and force equilibrium of the five DOFs. To calculate the error motions of the spindle, not only the imperfections of the shaft and bearings but also driving elements such as belt pulley and direct driving motor systems are considered.
Study on Dynamic Characteristics of Spindle-bearing System Subjected to Radial Load
Choi, Chun-Suk ; Hong, Seong-Wook ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 740~746
DOI : 10.7735/ksmte.2013.22.4.740
Angular contact ball bearings are often adopted for a high-speed spindle owing to their durability against axial and radial loads. The dynamic characteristics of an angular contact ball bearing, however, are very complicated because they are dependent on the applied loads as well as on the system configuration. This study systematically analyzes the radial-load-dependent characteristics of spindles as well as angular contact ball bearings. Toward this end, a spindle dynamic model along with the bearing dynamics model is established. An iterative solution algorithm is implemented to resolve the statically indeterminate problem associated with spindle-bearing systems subjected to radial load. Two numerical examples are provided to investigate the spindle and bearing characteristics as a function of radial load with regard to the system configuration.
Development and Evaluation of Ultra-precision Desktop NC Turning Machine
Ro, Seung-Kook ; Park, Jong-Kweon ; Park, Hyun-Duk ; Kim, Yang-Keun ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 747~754
DOI : 10.7735/ksmte.2013.22.4.747
This study introduces a recently designed desktop-sized NC turning system and its components. This machine is designed for the ultra-precise turning of parts with a diameter of 0.5-20 mm with minimum space usage for the machine. This study aims to achieve submicron-level accuracy of movements and good rigidity of the machine for precision machining using the desktop-sized machine. The components such as the main machine structure, air bearing servo spindle, and XZ stage with needle roller guides are designed, and the designed machine is built with a PC-based CNC controller. Its static and dynamic stiffness performances and positioning resolutions are tested. Through machining tests with single-crystal diamond tools, a form error less than
and surface roughness (Ra) of
for workpieces are obtained.
Variable PID Gain Control of Winder Tension of Roll-to-Roll Printing System using Estimation of Winder-Roll Radius
Park, Jong-Chan ; Jeon, Sung Woong ; Nam, Ki Sang ; Kim, Chung Hwan ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 755~760
DOI : 10.7735/ksmte.2013.22.4.755
The dynamics of the winder roller of a roll-to-roll printing system for printed electronics is a time-varying system because of the variation of the winder roller radius owing to rewinding or unwinding of the web. Therefore, an adaptive control method considering the time-variant characteristics is required for precise tension control. In this study, the variable PID gain method is applied to the actual roll-to-roll system and verified by experiments for unwinder tension control. The required value of the winder roller radius for the application of the variable PID gain is estimated from the measurement of the winder tension and winder motor torque. The simulation results as well as experimental results show that the fixed PID gain control cannot stabilize the tension of the winder roller with varying winder roller radius. On the other hand, the variable PID gain method can control the tension of the winder roller regardless of the winder roller radius.
Investigation of Friction Hysteresis in Miniaturized Linear Table Lubricated Withgrease
Ahn, Sung Woo ; Jeong, Young Hun ; Song, Chang Kyu ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 22, issue 4, 2013, Pages 761~766
DOI : 10.7735/ksmte.2013.22.4.761
A precision linear motion table plays a crucial role in manufacturing systems used in various industries such as machine tools, semiconductors, and nanofabrication. In particular, one of the most typical mechanisms for a linear motion table is to use a ballscrew and LM guides. However, this mechanism is inevitably influenced by friction because of the relative motion in its joint regions. One of the most complex phenomena in friction is the hysteresis behavior of dynamic friction, which was compared with the steady dynamic friction that was presented using a Stribeck curve in this study. Therefore, we investigated the dynamic friction and its hysteresis behavior using a miniaturized linear table equipped with a ballscrew and LM guides that were lubricated with grease. Subsequently, it could be seen that hysteresis could be considered a time delay after zero-velocity crossing and that it was influenced by acceleration.