• Korean Journal of Computational Design and Engineering
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• v.7 no.2
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• pp.102-109
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• 2002

This paper presents a method for automatic generating of check sheet to measure deep-drawn sheet metal. By using polyhedral model of CAD, the proposed procedure calculates measuring points automatically. The results of measure are exported to MS-Excel. The proposed method is implemented by API functions and C language using SPEED plus CAD/CAM system and MS-Window OLE.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.6
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• pp.981-988
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• 2008

This paper describes a development of automatic measuring device for cylinder liner wear amount. An operator should regularly measure the wear amount of the cylinder liner to prevent the wear amount of the cylinder liner from exceeding the maximum limit specific to the engine type. In previous methods. an operator entered the inside of the cylinder liner on a ladder and measured the amount of wear using a inside micrometer. Such method is unpleasant in severe environments and full of hazards. In addition, in order to enter the cylinder, the piston head had to be detached. requiring much time and money. In order to solve these problems, a new measuring device that consists of two measuring units and a special install jig is developed. The measuring units are installed through the scavenging air port by the install jig and measures the wear amount during 1 revolution of crankshaft. so detaching of the cylinder head and entering inside the cylinder liner are not required.

• Journal of the Korean Society of Mechanical Technology
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• v.13 no.4
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• pp.131-136
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• 2011

In commercial vehicle, sub-frame which equipped in main frame supporting dump deck and oil tanker. This is the main structure for all equipment which including joint function. Sub-frame is made by welding process, this susceptible to deform and crack by its longitudinal size. Also various kind of sub-frame make it difficult to standardization in manufacturing process and exclusive jig is not adapted yet. Frame size is over 6~8m and weight is more than 300kg this make re-work more difficult. If manufacturing company made precise sub-frame, this is not only convenient for customers but also save the company money by reducing the working time. In this study manufacture the sub-frame be suitable for its main function and develop exclusive welding jig for obtain checking fixture function as well.

• Transactions of Materials Processing
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• v.14 no.3 s.75
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• pp.200-206
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• 2005

In general, a lot of small electrode is needed for making precision injection molds, such as cell phone mold and precision connector mold, because of the limitations of NC milling process. Those small electrodes usually have very simple shapes and the actual cutting time is so short, but many NC programs and set-up process, a very complicated and time consuming Job, are needed for each electrode. This paper deals the method for increasing the productivity of machining electrodes. In this work, the process standardization of machining electrode was done and special jig fer machining small electrodes was developed. Automatic tool path optimization software was also developed to minimize tool changing time. In addition, in-line cutting tool measuring system was adopted. The productivity of machining for small electrode has been increased up to $100\%$.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.3
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• pp.89-95
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• 2014

The increasing level of demand for multi-tasking machines requires a saddle with an ultra-precise machining accuracy level of $15{\mu}m$, as such a saddle is one of the main components of these machines. The manner of achieving ultra-precise machining accuracy mainly depends on the fixed forces. In this paper, we optimized the number of contact points and the contact positions to reduce the deformation of the saddle while it is machined. The performance levels of the proposed optimal jig and fixture are determined by measuring the flatness, parallelism and perpendicularity of a machined saddle. The machining accuracy is found to be lower than $15{\mu}m$ at all measured points.

• Journal of the Microelectronics and Packaging Society
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• v.26 no.4
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• pp.69-74
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• 2019

The influence of measuring fixtures on the measurement of dielectric and piezoelectric properties of PMN-PT single crystal specimens was investigated. As the pressure of the jig pin which applied the AC electrical signal to the sample decreased, the lower resonance resistance was measured and the higher mechanical quality factor was calculated. The mechanical quality factor was 418 when the spring tension of the jig pin was 20grf, and the value of the quality factor was reduced by half when the spring tension was 200grf. The 4-probe fixture method is unsuitable for measuring piezoelectric properties, but it was suitable for the measurement of dielectric loss. In order to accurately evaluate the piezoelectric properties of PMN-PT, it is necessary to lower the spring tension of the jig pin as much as possible.

• The Journal of Advanced Prosthodontics
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• v.4 no.3
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• pp.153-157
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• 2012

PURPOSE. The study was conducted to compare the radiographic and clinical methods of measuring the horizontal condylar guidance (HCG) values. MATERIALS AND METHODS. The condylar guidance was measured using the radiographic (CT scan) and three clinical methods i.e. the wax protrusive records, Lucia jig record and intraoral central bearing device in 12 patients aged between 20-40 years irrespective of sex. The records were taken and transferred on the semi-adjustable articulator to record the HCG values. The CT scan was taken for 3D reconstruction of the mid facial region. Frankfort horizontal plane (FHP) and a line extending from the superior anterior most point on the glenoid fossa to the most convex point on the apex of articular eminence (AE) was marked on the CT scan. An angle between these two lines was measured on both right and left sides to obtain condylar inclination angle. Three interocclusal protrusive wax and jig records were taken and transferred to the semi adjustable articulator. Three readings were recorded on each side. Similarly the records were taken and transferred to the same articulator using the intra oral central bearing device to record the readings. RESULTS. The statistical analysis showed insignificant differences in the HCG values between the right and left sides [(P=.589 (CT), P=.928 (wax), P=.625 (jig), P=.886 (tracer)]. The clinical methods provided low Pearsons correlation values [(R = 0.423 (wax), R = 0.354 (jig), R = 0.265 (tracer)] for the right as well as the left sides when compared with the CT values. Among the clinical methods, jig and wax method showed strong level of association which is statistically significant while the intra-oral tracer showed weak association with the other two methods. CONCLUSION. The right and left HCG values were almost similar. The CT scan showed higher HCG values than the clinical methods and among the clinical methods, values obtained from all the methods were comparable.

• Polymer(Korea)
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• v.38 no.5
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• pp.645-649
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• 2014

The causes of residual stress in an injection molded part are high temperature variation and shear stress during molding process. Chemical cracking test is one of the methods of measuring residual stress and cracks are developed according to the degree of residual stress. In this study, the relationship between chemical cracking and exerted stress have been investigated. Deformation jig was designed and used to give a stress through deformation in a specimen. Specimens were molded by a hot press using polycarbonate (PC) and annealed to remove residual stresses in the specimens. Specimens were fixed in the deformation jig and immersed into the solvent to create cracks in the specimens. Solvents were prepared by using tetrahydrofuran and methyl alcohol. As stress accordance with the deformation in the specimen increased, the frequency and density of cracks in the specimen also increased. The results of this study can be used for the measurement of residual stress quantitatively in an injection molded PC product using a chemical cracking method.

• The Journal of Korean Society for Radiation Therapy
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• v.19 no.1
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• pp.19-26
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• 2007

Purpose: To compare of the accuracy among various measurement procedures of HDR Brachytherapy, and to evaluate the clinical suitability and usefulness of alternative PMMA (polymethylmethacrylateplastics: $C_5H_8O_2$) plate phantom without any additional cost due to the purchase of measuring apparatus. Materials and Methods: We made a comparative study on three types of measuring systems: well type chamber, source calibration jig, and PMMA plate phantom. Farmer type chamber was used for source calibration jig method and PMMA plate phantom method. Measurement was done 5 times each in comparison with the measurement values from manufacturer. Measurement results from experiment were compared with that from the manufacturer which is offered with the source whenever a source is substituted by a new one and evaluate the accuracy of source activity. Results: As a consequence of Ir-192 source measurement using well type chamber, source calibration jig and PMMA plate phantom, RMS (Root Mean Square) values for the relative error are 0.6%, 1.57%, 2.1%, respectively, compared with the data from manufacturer. And the mean errors with standard deviation are given $-0.2{\pm}0.5%$, $0.97{\pm}1.23%$, $-0.89{\pm}1.87%$ respectively. Conclusion: From the results shown by the three types of measurement system (well type chamber, source calibration jig, and PMMA plate phantom), the measurement with well type chamber produced the best accuracy. It turns out that we can also use the alternative system of PMMA plate phantom clinically without purchasing any additional particular apparatus since the system does not exceed the recommendation of AAPM (American Association of Physicists in Medicine), which requires the error range of within ${\pm}5%$.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.5
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• pp.824-829
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• 2012

The purpose of this study is to evaluate the proposed jig for turning process of large-scale aluminum tube of D500mm through Finite Element Analysis (FEA). Also, a machining evaluation is conducted with general heat-treated and cryogenic heat-treated tubes. Dimensions of the specimens are determined to be suitable for collet appearance. The characteristics of equivalent stress and strain according to the expansion of the collet are evaluated by FEA. The aluminum tubes which are heat-treated by T4/T6 condition and cryogenic condition are machined by using a large-scale lathe machine and the roundness of machined tube is evaluated by using a 3D measuring machine. Through the results of this study, effects of each heat treatment and residual stress on the roundness are established.