• Journal of Korean Institute of Industrial Engineers
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• v.20 no.4
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• pp.23-35
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• 1994

Efficient operation of a component placement machine with a multi-head in a PCB assembly process is considered. The problem consists of two subproblems, which are the optimal allocation of the component tape reels in the rack and the optimal mounting sequence of the components on a printed circuit board. We analyze the problem and propose a heuristic algorithm to solve it. The heuristic can be used for the one head case too. Computational experiences on some real world problems show the effectiveness of the heuristic in terms of speed and solution quality.

• Journal of the Korean Professional Engineers Association
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• v.16 no.3
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• pp.33-40
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• 1983

This paper is one of the case studies to improve the labor productivity of PCB assembly through Work Factor motion-time analysis and the application of the motion economy principles and the human factors engineering theory. In result, we can improve 129％ of the labor productivity by using a rotary table for the parts delivery. Therefore, it is expected that this result can be used for a lot of the manual works of the small and medium-sized industries especially.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.12
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• pp.6967-6972
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• 2014

Assembly using a bolt and nut, and rivet or pin have been used widely for forming mechanical joints. The indent method is an easier process than other manufacturing techniques and the toughness of the material is excellent. On the other hand, there are many cases in which the cracks occur on the manufacturing process as the indent method. Therefore, two kinds of models, in which a pin goes into and out PCB plate in this study were developed using the CATIA program and finite element methods were performed using the ANSYS program. When a pin was passed through a PCB plate in cases 1 and 2, the maximum loads applied to the PCB plate were 79.708N and 90.277N, respectively. When the PCB plate came out of the pin in cases 1 and 2, the maximum loads were 63.783N and 33.75N, respectively. The damage prevention and durability can be improved by applying the study results to the design of real indentation.

• IE interfaces
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• v.23 no.1
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• pp.58-67
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• 2010

The purpose of this paper is to present the development processes of the assembly line tester of power transmission for lift truck. Because power transmission is most important part of lift truck, all assembled powertrain parts must be inspected for operational defects, pressures and RPM. Developed assembly line tester is designed to take about 25 minutes for inspecting each assembled power transmission and located it at the end of assembled line. The assembly line no-load tester consists of three parts: (1) the driving hardware part; for installing and operating the transmission. (2) control PCB part; send data from sensors to a computer and control driving part, (3) operation software of no-load tester; for an automatic inspection or manual inspection, for database management and printing transcripts.

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2450-2452
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• 2003

We present a method to increase the productivity of multihead-gantry chip mounters for PCB assembly lines. To minimize the assembly time, we generate the mount sequence using the genetic algorithm. The chromosome, fitness function, and operators are newly defined to apply the algorithm. Simulation results are presented to verified the usefulness of the method.

• Journal of Ocean Engineering and Technology
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• v.14 no.4
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• pp.79-85
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• 2000

Press-fit pin connection is the solderless interference-fit between pins and plated through holes(PTH) in the printed curcuit board(PCB). Because of not only its simple assembly and absence of problems associated with soldering, but also its good mechanical and electrical characteristics, the press-fit pin connection technology has quickly gained wide acceptance in the telecommunications and computer industries. In this paper, the contact stress characteristics of the domestic CPF pin when inserted into the friction coefficients were compared and the stress variations of the compliant part of the pin, which have an influence on the performance, were displayed with the time and arc length after complete connected. It is supposed that the results will provide useful data to improve the performance of the pin-PCB interconnection mechanism.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.3
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• pp.276-282
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• 2015

This paper proposes a SMD (surface mounting device) classification method for the PCB assembly inspection machines. The package types of SMD components should be classified to create the job program of the inspection machine. In order to reduce the creation time of job program, we developed the automatic classification algorithm for the SMD packages. We identified the chip-type packages by color and edge distribution of the images. The input images are transformed into the HSI color model, and the binarized histroms are extracted for H and S spaces. Also the edges are extracted from the binarized image, and quantized histograms are obtained for horizontal and vertical direction. The neural network is then applied to classify the package types from the histogram inputs. The experimental results are presented to verify the usefulness of the proposed method.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.8
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• pp.697-702
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• 2000

The paper considers the problem of improving the productivity of surface mounting in the printed circuit board(PCB) assembly line. This problem is generally divided into two problems ; real assignment problem and pick-and -place sequencing problem which are known to have no polynomial time algorithms. In the last ten years algorithm designers have been trying to solve them separately. However they need to be solved jointly because they are highly interrelated. This paper proposes an evolutionary algorithm which can consider the two problems jointly and thus yield a better solution. In order to evaluate the proposed algorithm computer simulation is performed on real-life surface mounting machines. The proposed algorithm is expected to reduce the assembly time of surface mounting machines and thus improve the productivity.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.2
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• pp.225-230
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• 2009

We propose a template matching method for component inspection of SMD assembly system. To discriminate wrong assembled components, the input image of component is matched with its standard image by template matching algorithm. For a fast inspection system, the calculation time of matching algorithm should be reduced. Since the standard images of all components located in a PCB are stored in computer, it is desirable to reduce the memory size of standard image. We apply the discrete wavelet transformation to reduce the image size as well as the calculation time. Only 7% memory of the BMP image is used to discriminate goodness or badness of components assembly. Comparative results are presented to verify the usefulness of the proposed method.

• Transactions on Electrical and Electronic Materials
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• v.13 no.3
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• pp.129-135
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• 2012

A number of surface mount technology (SMT) process variables including land design are considered for minimizing tombstone defect in flexible printed circuit assembly in high volume manufacturing. As SMT chip components have been reduced over the past years with their weights in milligrams, the torque that once helped self-centering of chips, gears to tombstone defects. In this paper, we have investigated the correlation of the assembly process variables with respect to the tombstone defect by employing statistically designed experiment. After the statistical analysis is performed, we have setup hypotheses for the root causes of tombstone defect and derived main effects and interactions of the process parameters affecting the hypothesis. Based on the designed experiments, statistical analysis was performed to investigate significant process variable for the purpose of process control in flexible printed circuit manufacturing area. Finally, we provide beneficial suggestions for find-pitch PCB design, screen printing process, chip-mounting process, and reflow process to minimize the tombstone defects.