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A hot runner system can provide many advantages to plastic injection mold engineers for improving product quality. In edge gate systems in particular, the gate traces can appear on the side of products rather than the top. However, it is difficult to establish hot runner systems using edge gates because of their structural differences from conventional gate systems. This article presents the entire process of preparing a 48-cavity plastic injection molding system with edge gates. This process consists of 48-cavity injection mold design, structural analysis, verification of design plans, filling analysis of multi-cavity, cooling channel design on the basis of cooling analysis, fabrication of the mold system, and test injection. All presented computer-aided engineering analyses were conducted using ANSYS and MoldFlow.

This paper presented a study about maximum stresses acting on the 4-dish solar collector system, which caused by excessive wind. For this, Central Composite Design and Response Surface Method were used on the basis of maximum stresses calculated by Finite Element Method. VisualDOC was used for CCD (Central Composite Design) and RSM (Response Surface Method), and Ansys was used for FEM (Finite Element Method) analysis. 9 cases of CCD points were selected and FEM analyses were conducted at these points. Based on these results, response surface function was constructed to model maximum stresses as function of wind velocity and thickness of dish support bar. In order to evaluate RSM model, arbitrary point were selected, and maximum stresses calculated by RSM were compared with those calculated by FEM.

This paper presented characterization of spray velocity and angle of spray nozzle systems for cosmetic products. Diameter and length of nozzle orifice were chosen as shape factors of the spray system. Combinations of the factors were determined by using Central Composite Design. Fluid analysis was conducted by using Fluent to obtain spray angle and velocity. RSM (Response Surface Method) was used to approximate the relationship between these 2 factors and spray characteristics. To evaluate the proposed method, experimental work with existing was conducted and good agreement between simulation and experimental results.

This paper presents an improved experimental equation for representing wave spring behaviors. Wave springs were widely used for automobile automatic transmission and have to be precisely controlled. In fact an experimental equation was provided by mechanical design handbook. However the accuracy of the equation is not suitable. Therefore we tried to optimally modify correction factor K used in the equation without modifying the whole equation. For this different models of springs were manufactured to test and simulate. Theses results were analyzed and redefined correction factor K. To evaluate the proposed approach modified correction factor K was applied into various models and good agreement was obtained.

This paper presents a series of injection process simulations for blow molding preforms by using MoldFlow. The injection-blowing system was used and this consists 3 stages on the same machine; (1) preform injection, (2) blowing and (3) ejection. The quality of preform injection process is an important factor that can dominate the whole process efficiency. The injection mold system consists of 10 cavities and a hot runner system. The hot runner system has 10 cavities and temperature of each cavity can be independently controlled. Through several filling analyses, suitable temperature of each gate was determined so that all cavities could be simultaneously filled. Weld lines on the bottom of preforms were predicted. This fact can be an important aspect because preforms will be blown. To improve cooling efficiency, ''Floody Cooling Type" channels were applied. Conventional cooling channels were straight-line types and then distances between cooling channels and cavities cannot be uniformed. Floody cooling type channels were uniformly placed around cavities as far as possible. To compare two different types of cooling channels, cooling tests of MoldFlow were carried out and certain advantages of floody cooling type channels were evaluated.

This study presents a determination procedure of optimal shot-peening process conditions, wave profiles and thickness in order to precisely control and improve durability and fatigue life of wave cushion springs assembled into automobile automatic transmission clutch. For this shot-peening process, residual stress analysis was applied under various conditions. Experimental works were conducted to evaluate proposed approach by using X-ray diffraction residual stress measurement tester. It could be expected that this study provided guideline for wave spring optimal design and improving fatigue life.

This study was to accomplish a design process of 10-sp cassette system consisting of different material sprockets and a spider. Main purpose of this design was developing a lightweight and highly efficient cassette system for road bicycle. For this it is necessary to determine the materials and the shapes considering various important factors. Especially sprockets of 10-sp cassette system must become thinner than sprockets of low speed cassettes. Thus it is necessary to carry out a series of structural analyses so as to secure sufficient mechanical strength and rigidity. To verify the safety of this system, a series of finite element analysis was conducted under various boundary conditions. Single sprocket analysis and assembled parts separately were analyzed and compared each other. The analysis results were sufficiently satisfied. In fact how to manufacture the system must be considered.

This paper investigates a design optimization for "Bone Plate System" which can directly fix human bones fractured. The active trauma system consists of several shaped bone plates and implant screws for fixation of fractured human bones with various manual instruments allowing to handle them. The material corresponds to titanium because it was well known as harmless material when being inserted into human body. This system has to be suitably rigid as well as manually bended in orthopedic surgery operations. Then bone plates have to be designed with suitable shapes. In order to verify whether bone plates were well designed, a series of bending tests. However optimized shapes of bone plates have to be determined before unnecessary a number of bending tests. For this purpose FEM(Finite Elements Method) was applied during design process which allows us to investigate the bending strengths of bone plates. Based on FEM results, dimensions of bone plates were optimized in order to be suitably rigid without actual bending tests.

Abstract: In this study, a useful indirect cutting force measurement method using an acceleration sensor and current hall sensors is proposed. A series of experiments was performed on a precise micro machining stage with a high-speed spindle. A three-axis acceleration sensor was installed on the spindle head, and current hall sensors were connected to the motor current inlet cables. From the results obtained, the correlations of the tool teeth rotation and current amplitude showed a linearity of 92.0% precision for hall sensor signals, and 98.0% precision for acceleration sensor signals. Even though the results using the acceleration sensor showed better linearity than those of the current hall sensors, the signals can be easily affected by chattering, spindle vibration, and other external disturbances. From this perspective, the current hall sensor can provide more robust results.

Recently the polymeric LOC (lab-on-a-chip) has been developed by the bio technology and the micro electro mechanical system technology. It is possible that biological experiment and analysis is executed rapidly and easily using a simple specimen. Therefore, many researches on LOC are progressing actively in various fields such as medical, biotechnical, environmental aspects etc. Up to the present time, most of polymeric LOC has been manufactured by LIGA (lithograpie galvanofomung abformung) or chemical etching processes. However, these methods have several disadvantages which are the complicated fabrication stages, requirements for various special equipments and limitations of materials. In this study, in order to overcome these difficulties, the possibilities of micro fluidic channel features were executed by micro cutting process for the steel. So the micro mold insert with micro fluidic channel was designed and manufactured by micro cutting process for the injection molding.

Recently, ultra-precision micro patterns and shapes have been widely used in optical field. Various methods which are based on semi-conductor fabrication methods are nowadays used in fabrication of micro shapes and patterns, but micro endmilling technology has lately attracted considerable attention because of various available materials, flexibility of process and high-productivity. For the precision micro endmilling process, analysis of micro cutting error is mandatory. In general, tool deflection is a major factor which causes cutting error and limits realization of the high-precision cutting process. Specially, in micro endmilling process, micro tool deflection generates very serious problems compared to macro tool deflection. In this paper, it is performed to observe the real tool deflection shapes in micro endmilling process, so the trend of micro tool deflection was analyzed using real captured images in this study. To get the real images of micro tool deflection, micro slot cutting processes were executed under various cutting conditions using micro endmill and the real images of tool deflection were obtained during cutting process by high-speed camera. Finally, the extent of tool deflection was calculated by the deflection angle according to cutting conditions and two trends (the point of first tool contact and the cutting stage) of micro tool deflection were analyzed.

Recently, the trends of industrial products move towards more miniaturization, variety and mass production. Micro drilling which take high precision in cutting work is required to perform more micro hole and high speed working. Especially, Micro deep hole drilling is becoming more important in a wide spectrum of precision production industries, ranging from the production of automotive fuel injection nozzle, watch and camera parts, medical needles, and thick multilayered Printed Circuit Boards(PCB) that are demanded for very high density electric circuitry. The industries of precision production require smaller holes, high aspect ratio and high speed working for micro deep hole drilling. However the undesirable characteristics of micro drilling is the small signal to noise ratios, wandering motion of drill, high aspect ratio and the increase of cutting force as cutting depth increases. In order to optimize cutting conditions, an experimental study on the characteristics of micro deep hole machining processes using a tool dynamometer was carried out. And additionally, microscope with built-in an inspection monitor showed the relationship between burr in workpieces and chip form of micro drill machining.

In this study, micro powder blasting techniques are applied to micro-pattern making process using developed Si3N4-hBN composites. Material properties of the developed machinable ceramics according to the variation of h-BN contents, those are used to give good machinability to the ceramics, are evaluated. And, a series of required experimental works are performed to determine optimum powder blasting conditions for micro-pattern making. The experiments are performed for the prepared samples with no mask, and samples with three different mask patterns. As the results, it can be observed that the machinability of the developed Si3N4-hBN composites increases as the h-BN contents in the composites. Also, from the experimental results, it is possible to determine the optimum blasting conditions for micro-pattern making process with Si3N4-hBN composites.

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Abstract: This paper presents a sculptured surface recognition and localization strategy for the inspection process using the CMM. First, the database is generated from the CAD data based on the Z-Layer concept. Then, the three-dimensional shape of the object on the CMM table is constructed using a vision guided CMM. Two vision cameras are implemented to guide the CMM to the object, and B-spline interpolation method is applied to generate a surface that passes through the obtained data points. As a following step, the Z-layers of the generated surface are created and the geometric properties are calculated to determine the best matching surface in the database. Rough location and orientation of the object are determined by analyzing the image data, and the minimization algorithm is applied as a next step to obtain more accurate localization results. The experimental results show that the proposed method can be applied effectively for sculptured surface recognition and localization in the inspection processes.

Abstract: The objective of this paper is to deal with the deflection effects of cutting tools. Deflection is an important factor in obtaining accurate surfaces in milling operations. We have tried to integrate tool deflection effects for tool path generation in flat-end milling without modifying the cutting conditions. To carry out our objective, a tool path compensation methodology is presented. The cutting forces are modeled on the specific cutting pressureK T andK R, determined experimentally. The calculations of tool deflection by both the Finite Element Method and the Cantilever Beam Model are compared and integrated in the tool path compensation process. An experimental example is presented to illustrate and verify our approach proposed in this paper. As a result, it can be seen that the proposed approach can be implemented into real-life situations effectively.

Abstract: In this paper, we present the optimum reference for the compensation of tool trajectory to fulfill the imposed tolerances in flat-end milling process. First, we suggest the milled surface prediction methods considering the tool deflection effects. Based on the predicted error distributions, we propose a cutting process simulation method, which can verify (1) if the tolerance is fulfilled, and (2) if it is possible to compensate the surface errors by the proposed approaches presented in Part I, before the real milling operation begins. As the result of our research, we could make our compensation method very applicable for real industrial cases by considering the imposed manufacturing tolerances. Required experiments for practical examples were performed, and it was found that the results were in good agreement with our predictions.