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2018 Society of Plastics Engineers Annual Technical Conference, ANTEC 2018

作者： Chen, Jian-Yu Huang, Ming-Shyan Nian, Shih-Chih Bachelor Program of Precision System Design Feng Chia University Taiwan Dept. of Mechanical and Automation Engineering National Kaohsiung First University of Science and Technology Taiwan Dept. of Power Mechanical Engineering National Taitung College Taiwan

Injection molding is one of the most common methods for the mass production of plastic products with complex geometries. However, while injection molding is a highly convenient and cost-effective method, some problems still remain, including warpage, quality variations, surface defects, insufficient physical properties of the finished parts, and so on. During the ejection stage, one of the most serious problems is that of sticking at the interface between the molded part and the cavity surface. The adhesion force inhibits the release of the molded part from the mold surface, and can lead to serious defects, such as distortion and cracking. The adhesion phenomenon is particularly common in the injection molding of thermoplastic polyurethane (TPU). Numerous factors affect the intensity of the mold adhesion force, including the injection molding conditions, the surface morphology, the surface modification conditions, and the rheological properties of the molten polymer. To clarify the effect of the molding conditions on the mold adhesion level, the present study uses a tensile mode mold adhesion tester to measure the adhesion force for various values of the mold temperature, melt temperature and injection speed. In addition, the surface free energy (SFE) of the molded parts is measured in order to better understand the correlation between the wettability and the processing conditions. © 2018 Society of Plastics Engineers. All rights reserved.

关键词： Injection molding

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Online measurement of polymer melt viscosity in injection molding 75

Online measurement of polymer melt viscosity in injection mo...

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75th Annual Technical Conference and Exhibition of the Society of Plastics Engineers, SPE ANTEC Anaheim 2017

作者： Huang, Ming-Shyan Nian, Shih-Chih Chen, Jian-Yu Yang, Kai-Jye Tseng, Jian-Chou Dept. of Mechanical and Automation Engineering National Kaohsiung First University of Science and Technology Taiwan Dept. of Power Mechanical Engineering National Taitung College Taiwan Bachelor Program in Precision System Design Feng Chia University Taiwan

ISBN: (纸本)9780692883099

Melt viscosity, determined by the shear rate, barrel temperatures, and pressure during plasticization, greatly affects the flow ability of polymer melts as well as the quality of injection-molded parts. In particular, the consistency of molding qualities is highly relevant to the plasticizing quality at each cycle (i.e., injection molding requiring a high yield rate highly relies on the stability of polymer melts). However, numerous factors affect the plasticizing quality, including the geometry of injection screws, processed polymer materials, processing parameters of plasticization such as the feeding rate, screw rotational speed, barrel temperatures, back pressure, and screw backward speed. The conventional approach of plasticization in injection molding machines uses a single reciprocating screw for conveying, melting, and metering polymer melts. The plasticizing quality is roughly adjusted by indirectly controlling barrel temperatures;thus, the melt viscosity varies. An in-suit approach of assuring melt quality is to measure the melt viscosity variation online, which is a more suitable indicator of the plasticizing quality than temperature. This study thus monitored the melt viscosity variations in polymer melts by using in-mold pressure sensors. Furthermore, the effects of the injection velocity and mold temperature on the melt viscosity variations were examined.

关键词： Polymer melts

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Parametric Analysis on the Geometry of Magnetic system for Subwoofer with FEMM

Parametric Analysis on the Geometry of Magnetic System for S...

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2018 3rd International Conference on Computational Modeling, Simulation and Applied Mathematics (CMSAM 2018)

作者： Yu-Cheng Liu Shu-Chien Wu Jiun-Yen Chen Bachelor's Program in Precision System Design Feng Chia University Master's Program of Electro-Acoustics Feng Chia University

The aim of this study is to investigate the distributions of magnetic flux and the variations in B curve for a novel design of loudspeaker magnetic system. Two different geometries, simulated with commercial finite element software-(FEMM) are presented, as well as an optimized design for the geometry of magnetic system. Results showed that changes in the inner side geometry obviously influence the distributions of magnetic field. In addition, the maximal magnetic force shifts to the position of lowest cross-sectional area. Meanwhile, B curve not only reduces the B level, but also loses the original uniformity in the air gap. Thus, the distortion caused from magnetic system will increase. Based on the original design, the new design not only maintains the flat B curve, but also saves on the amount of material of required for the magnetic system by around 31%.

关键词： Subwoofer Magnetic flux B curve NRT Finite element method

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Study on the Characteristics of Acoustic Radiation of Microspeaker Associated with Pattern of Diaphragm with Finite Element Method

Study on the Characteristics of Acoustic Radiation of Micros...

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2018 3rd International Conference on Computational Modeling, Simulation and Applied Mathematics (CMSAM 2018)

作者： Yu-Cheng Liu En-Tzu Chang Hung-Wei Chen Bachelor's Program in Precision System Design Feng Chia University Master's Program of Electro-Acoustics Feng Chia University

The objective of this study is to investigate the acoustic radiation of Microspeaker based on various pattern geometries of diaphragm. The influence of first resonant frequency(f) is discussed, as are the radiation efficiency(SPL) and impedance curve(IMP). First, microspeaker geometry was reconstructed with CAD software(Creo). Four geometric pattern parameters, width, angle, depth, and quantity, of microspeaker diaphragm were defined and simulated with commercial finite element software-COMOSL Multiphysics. Results showed that the quantity and depth of pattern significantly influenced on the acoustic radiation, especially at lower frequencies. The stiffness of diaphragm decreased with increases in quantity and depth of pattern. In addition, f for both conditions shifted to lower frequency and bandwidth of microspeaker was extended. Increasing the angle of pattern, resulted in more solid diaphragm and slight increase in efficiency.

关键词： Microspeaker Pattern of diaphragm Finite element method

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A Methodology for Longitudinal Tooth Flank Crowning of the Helical Gear on a CNC Honing Machine

A Methodology for Longitudinal Tooth Flank Crowning of the H...

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2014 2nd International Conference on Future Materials Engineering and Industry Application(ICFMEIA 2014)

作者： Van-The Tran Ruei-Hung Hsu Chung-Biau Tsay Program of Mechanical and Aeronautical Engineering Feng Chia University Program in Precision System Design Feng Chia University Department of Mechanical and Computer-Aided Engineering Feng Chia University

The gear honing is the most economical way for hard finishing an involute helical gear after hobbing and heat treatment or after shaving and heat treatmentThe gear honing can also be applied to the modification of gear tooth surfaces to compensate for the distortions that occur during heat treatment processMost published papers on the technology of gear honing describes on the principle of generated gear surfaceHowever, the longitudinal tooth flank crowning of a helical gear with honing has not been investigated yetTherefore, in this paper, we proposed a novel method for longitudinal tooth flank crowning of work gear surfaces by setting a crossed angle between the honing cutter and work gear axes as a linear function of honing cutter's traverse feed in the honing processA mathematical model for the tooth profile of work gear honed by a standard honing cutter is also establishedThree numeral examples are presented to illustrate and verify the merits of the proposed gear honing method in longitudinal crowning.

关键词： Gear honing Longitudinal crowning Tooth flank Helical gear Mathematical model

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A Numerical Method for Reversely Generating a Pair of Conjugated Rotor Profiles of Twin-screw Compressor from the Measured Profile Data

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Procedia CIRP 2017年 63卷 483-487页

作者： Ruei-Hung Hsu Yu-Ren Wu Zi-An Chen Bachelor's Program in Precision System Design Feng Chia University Taiwan R.O.C. Department of Mechanical Engineering National Central University Taiwan R.O.C.

Reverse engineering technique is generally practiced to reconstitute the original conjugated rotor profiles from the measured point data with profile deviation for further evaluating performance of the competitor's same-level products in the twin-screw compressor manufacturing industry. However, it is time-consuming when synthesizing and restoring the original rotor profiles via either trial or enveloping methods. This paper proposed a numerical method, named meshing clearance elimination (MCE) method, for approaching pairs of conjugated male and female rotor profiles from the discrete measured profile points. By using this method, the clearance between two screw rotors can be attained via the normal rack generation computation and then eliminated by proportionally distribute the normal compensation onto the measured rotor profiles to obtain the “ideal” rotor profiles to avoid numerical divergence in the following compressor performance computation. Two kinds of rotor profiles measured from CMM (Coordinates Measurement Machine) were demonstrated in the numerical examples to show the effectivity and advantages of the MCE method.

关键词： twin-screw compressor rotor profile meshing clearance

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Variations in the acoustic measurement of earbud earphones in an ane-choic chamber due to changes in the earphone placement in ear Concha

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Canadian Acoustics - Acoustique Canadienne 2020年第4期48卷 29-40页

作者： Pawar, S.J. Liu, Y.C. Huang, Jin H. Department of Applied Mechanics Motilal Nehru National Institute of Technology Allahabad Prayagraj India Bachelor's Program in Precision System Design Feng Chia University Taichung Taiwan Department of Mechanical and Computer-Aided Engineering Feng Chia University Taichung Taiwan

The growth of consumer electronic products is encouraged by innovations and has stimulated the persistent development of earphones for high-quality sound reproduction. Earbud earphone is located in the concha of the human ear facing an ear-canal. The placement of earphones in the concha plays a remarkable role in the sound pressure level response of an earphone. In this study, ten earphones were tested for frequency response and total harmonic distortion using head and torso simulator in an anechoic chamber. Three positions and two orientations of earphones in the concha were identified for measurement. Based on the responses of all earphones at all orientations and positions, it is concluded that there is a variation in the frequency response and total harmonic distortion. Even though the variation is small in magnitude, its effect on sound perception, sound exposure, and the hearing threshold is phenomenal. Based on the proposition presented in this work and the safe daily sound exposure, it has been determined that the variation in the frequency response affects the perceived loudness of sound and can cause signif-icant differences in the daily sound exposure limit for a human being. © 2020, Canadian Acoustical Association. All rights reserved.

关键词： Frequency response

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Application of programmable Logic Controller to Build-up an Intelligent Industry 4.0 Platform

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Procedia CIRP 2017年 63卷 150-155页

作者： Jian-Yu Chen Kuo-Cheng Tai Guo-Chin Chen Bachelor's Program of Precision System Design Feng Chia University No. 100 Wenhwa Rd. Seatwen Taichung 407 Taiwan Department of Mechanical and Computer-Aided Engineering Feng Chia University No. 100 Wenhwa Rd. Seatwen Taichung 407 Taiwan

Industry 4.0 is initiated by the German government as a high level technology strategy in order to keep Germany in a global leading position in manufacturing, also intends to solve energy and aging issues in parallel. Germany has proposed the “Reference Architecture Model Industries 4.0” which is based on the regulations published by the International Electrotechnical Commission. The manifestation of Industry 4.0 can be achieved by the realization of digital factory. And it's emphasized on total integration with Cyber Physical system as its core technology, via Internet of Things to realize the operational environment of human machine interaction, and the utilization of Big Data for decision making. The research motivation of this thesis is to utilize Totally Integrated Automation Portal as a digital factory software development platform, to achieve the fundamental educational requirements of digital factory, and to understand Industry 4.0 concept. Methodology of this research is based on a set of experimental and training mechanism, the sequence of machine movements is controlled by a programmable Logic Controller, and this PLC has to be complied with IEC61131 International Standard. Regarding communication technology also to be complied with IEC61158 and IEC62541 e.g. PROFINET and OPC UA protocol. And finally realizing the operational environment of human machine interaction via smart phone according to the outcome of this research, it has been shown that total integration concept can be realized by single production machine. By standardization of factory environment and increasing the level of operational environment of human machine interaction, productivity and quality of production could be significantly increased. PLC could be used to analyze intelligent platform and comply with the Industry 4.0 standard at the same time.

关键词： I4.0 Digitalization Factory PLC and IEC61131

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Quality Monitoring Methodology for Micro-Shrinkage of Thick-Walled Injection Molded Components

SSRN

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SSRN 2022年

作者： Huang, Ming-Shyan Chen, Jian-Yu Xiao, Yu-Qi Department of Mechatronics Engineering National Kaohsiung University of Science and Technology 1 University Road Yanchao Dist. Kaohsiung City824 Taiwan Bachelor’s Program of Precision System Design Feng Chia University 100 Wenhwa Road Seatwen Taichung City40724 Taiwan

Sink mark degrades the surface quality of the thick-walled injection molded components. An effective method for quantifying sink marks, and predicting the occurrence of such defects as a function of the injection molding process parameters, are of significant interest in improving the molding quality. The present study proposes a method for measuring the micro-shrinkage using a simple image-processing technique. Simulation and experimental trials are performed to investigate the effects of injection molding parameters on the quality of the polymer melt (as evaluated using quality indexes extracted from the pressure profiles within the chamber and the tie-bar elongation, respectively) and the quality of the final molded component. The sink mark is determined mainly by the holding pressure. The quality indexes revealed in this study are all highly correlated with micro-shrinkage. They provide a viable means of predicting the formation of sink marks and excessive micro-shrinkage in thick-walled injection molded components. © 2022, The Authors. All rights reserved.

关键词： Injection molding

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A first-principles study on the quantum tunneling of methylhydroxycarbene isomerization in various solvents 4

A first-principles study on the quantum tunneling of methylh...

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4th Padjadjaran International Physics Symposium 2019, PIPS 2019

作者： Susanti, E.D. Rusydi, F. Puspitasari, I. Fadilla, R.N. Aisyah, N.D. Ahmad, A. Research Center for Quantum Engineering Design Faculty of Science and Technology Universitas Airlangga Jl. Mulyorejo Surabaya60115 Indonesia Department of Physics Faculty of Science and Technology Universitas Airlangga Jl. Mulyorejo Surabaya60115 Indonesia Precision Sciences and Technology and Applied Physics Graduate School of Engineering Osaka University Suita565-0871 Japan Information System Study Program Faculty of Science and Technology Universitas Airlangga Jl. Mulyorejo Surabaya60115 Indonesia School of Chemical Science and Food Technology Faculty of Science and Technology Universiti Kebangsaan Malaysia Bangi Selangor43600 Malaysia

Quantum tunneling phenomenon allows a high-barrier reaction to occur even though thermal energy is not sufficient to surmount the barrier. The phenomenon has been suggested to exist in the isomerization of methylhydroxycarbene which occured at 11 K. Here we study the quantum tunneling that occured in the isomerization of methylhydroxycarbene to acetaldehyde and to vinyl alcohol based on density functional calculations. The isomerization pathways are determined under the effect of various solvents which are modeled by polarizable continuum model (PCM). We use Wentzel-Kramers-Brillouin (WKB) approximation to calculate the tunneling probability (T) and extend the usefulness of T into isomerization rate. The results show that the solvents give a significant effect on the isomerization rate of methylhydroxycarbene to acetaldehyde but an insignificant one on the isomerization rate to vinyl alcohol. © 2020 IOP Publishing Ltd. All rights reserved.

关键词： Isomerization

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