• 한국시뮬레이션학회논문지
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• 제17권2호
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• pp.1-12
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• 2008

자동차 엔진을 구성하는 주요부품은 실린더블록, 실린더헤드, 크랭크샤프트, 커넥팅로드, 캠샤프트 등으로 구성되는데 이들의 영문명을 따서 5C라고 부른다. 따라서 일반적으로 엔진공장은 5C를 생산하는 라인과, 엔진 조립라인을 포함하는 6개의 라인으로 구성이 된다. 엔진공장은 소품종대량생산의 특성을 가지기 때문에 장비의 배치형태는 흐름라인의 형태를 따른다. 본 논문에서는 국내 자동차 회사 엔진공장의 크랭크샤프트라인 설계를 위한 시뮬레이션 사례를 소개한다. 크랭크샤프트 라인은 기계가공을 중심으로 하는 라인이다. 따라서 라인설계에 영향을 미치는 요인들에 대해 소개하고, 라인 효율에 미치는 영향을 $QUEST^{(R)}$라는 3차원 시뮬레이션 도구를 이용하여 분석하였다. 기술팀에서 제시한 초기배치안에 대해 시뮬레이션 모델을 구축한 후 실험을 통하여 시스템 효율을 개선시키기 위한 방법을 제시하였다.

• 한국자동차공학회논문집
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• 제3권5호
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• pp.10-16
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• 1995

In this study, the optimum design is carried out upon the crankshaft of in-line 6-cylinder internal combustion diesel engine with the mechanical analysis for the layout design, which is standard calculation whose process contains quadratic curve fitting method and quasi newton method about cost function, design variables and constraint conditions, Without finite element analysis, this process in wich mechanical analysis is performed upon the most critical part in crankshaft gives necessary and satisfied output in layout design and saves time and cost in developing a new diesel engine. In this study, also, the 3-dimensional finite element method is used in confirming the standard calculation for the optimization of crankshaft and the shape optimization in crankweb is obtained.

• 대한산업공학회지
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• 제40권5호
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• pp.481-491
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• 2014

In this paper, we discussed a problem for improving the throughput of a crankshaft manufacturing line in an automotive factory in which the budget for purchasing new machines and installing additional buffers is limited. We also considered the constraint of available space for both of machine and buffer. Although this problem seems like a kind of buffer allocation problem, it is different from buffer allocation problem because additional machines are also considered. Thus, it is not easy to calculate the throughput by mathematical model, and therefore simulation model was developed using $ARENA^{(R)}$ for estimating throughput. To determine the investment plan, a modified Arrow Assignment Rule under some constraints was suggested and it was applied to the real case.

• 센서학회지
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• 제31권1호
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• pp.51-56
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• 2022

In this study an efficient method for detecting and monitoring engine misfiring, focusing on minute speed changes in the crankshaft is proposed., Its validity is verified using various misfiring cases. Typically, the crankshaft speed fluctuates around the normal value depending on the engine misfiring status. Even a minute speed change in the crankshaft can be estimated by measuring the rotation time of each tooth of the 118-tooth flywheel attached to the crankshaft with a 2-MHz timer. Therefore, a speed pattern for an in-line six-cylinder engine consists of 236 tooth rotation speeds corresponding to the two rotations of the crankshaft, in which all the cylinders complete four-stroke cycle. FFT analysis can reduce the number of components of a speed pattern from 236 to just four major components: - fundamental frequency_(f), 2f, 3f, 6f., - This makes the comparison of the misfiring cases simpler and faster. In the experiment, five engine status cases (one normal firing and, four misfiring cases) were simulated. While the 6f component was the largest for the normal case, the f component increased as misfiring occurred one, two apart, and two consecutive times. The 3D FFT pattern comprising the ratio of f, 2f, and 3f, 6f showed that the distance between the misfiring and normal states was larger

• 한국자동차공학회논문집
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• 제8권1호
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• pp.148-156
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• 2000

For the in-line three cylinder engine whose crankshaft has a phase of 120 degrees, the total sum of unbalanced inertia forces occurring in each cylinder will be counterbalanced among three cylinders. However, parts of inertia forces generated at the No.1 and No.3 cylinders will cause a primary moment about the No.2 cylinder. In order to eliminate this out-of-balance moment, a single balance shaft has been attached to the cylinder block so that the engine durability and riding comfort may be further improved. Accordingly, the forced vibration analysis of the in-line three cylinder engine must be implemented to meet the required targets at an early design stage. In this paper, a method to reduce noise and vibration in the 800cc, in-line three cylinder LPG engine is suggested using the multibody dynamic simulation. The static and dynamic balances of the in-line three cylinder engine are investigated analytically. The multibody dynamic model of the in-line three cylinder engine is developed where the inertia properties of connecting rod, crankshaft, and balance shaft are extracted from their FE-models. The combustion pressure within the No.1 cylinder in three significant operating conditions(1500rpm-full load, 4000rpm-full load and 7000rpm-no load)is measured from the actual tests to excite the engine. The vibration velocities at three engine mounts with and without balance shaft are evaluated through the forced vibration analysis. Obviously, it is shown that the vibration of the in-line three cylinder engine with balance shaft is reduced to the acceptable level .

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 후기학술대회논문집
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• pp.53-54
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• 2005

This paper describes that send some signal from encoder attached to crankshaft of marine-engine to measuring instrument using power line modem(PLM) and display cylinder pressure, rpm and etc. on LCD. Conventional method that sends signal along the long signal line has some inconvenience from too long signal line length caused by huge volume of ship's engine. Power line modem can have short signal line from outlets to measuring instrument. Because it use exist power line for send signals, so it have low installation cost and could have good merits in job sites. Through this experiment, pressure in cylinder, engine rpm and etc. signals through PLM are well recognized at measuring instrument.

• International Journal of Automotive Technology
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• 제8권5호
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• pp.637-650
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• 2007

A new on-line fault detection and isolation(FDI) scheme has been proposed for engines using an adaptive neural network classifier; this paper investigates the robustness of this scheme by evaluating in a wide range of operational modes. The neural classifier is made adaptive to cope with the significant parameter uncertainty, disturbances, and environmental changes. The developed scheme is capable of diagnosing faults in the on-line mode and can be directly implemented in an on-board diagnosis system(hardware). The robustness of the FDI for the closed-loop system with crankshaft speed feedback is investigated by testing it for a wide range of operational modes, including robustness against fixed and sinusoidal throttle angle inputs, change in load, change in an engine parameter, and all changes occurring simultaneously. The evaluations are performed using a mean value engine model(MVEM), which is a widely used benchmark model for engine control system and FDI system design. The simulation results confirm the robustness of the proposed method for various uncertainties and disturbances.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.71-74
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• 2005

More than five pulleys are used in an automobile, such as crankshaft, water pump, air-con compressor, fan and power steering pump pulley. These pulleys are parts that need durability until retiring a car. But there is no design criterion for durability, so pulleys are designed by the experience of designer and trial and error. So, in this study, we carried out stress analysis at durability test condition and compared analysis results to durability test results. It is found that the design criterion for durability is defined as a safety factor and a safety factor is different according to the distance between the center line of v-grooves and the mating surface.

• Journal of Electrical Engineering and Technology
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• 제11권3호
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• pp.609-617
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• 2016

Belt-driven Starter Generator (BSG) differs from other mild hybrid systems as the crankshaft of vehicle are not run off. Motor permits a low-cost method of adding mild hybrid capabilities such as start-stop, power assist, and mild levels of regenerative braking. Wound rotor synchronous motor (WRSM) could be adopted in BSG system for HEV e-Assisted application instead of the interior permanent magnet synchronous motor (IPMSM). In practice, adequate torque is indispensable for starter assist system, and energy conversion should be taken into account for the HEV or EV as well. Particularly, flux weakening control is possible to realize by adjusting both direct axis components of current and field current in WRSM. Accordingly, this paper present an off-line current acquisition algorithm that can reasonably combine the stator and field current to acquire the maximum torque, meanwhile the energy conversion is taken into consideration by losses. Besides, on account of inductance influence by non-uniform air gap around rotor, nonlinear inductances and armature flux linkage against current variation are proposed to guarantee the results closer to reality. A computer-aided method for proposed algorithm are present and results are given in form of the Look-up table (LUT). The experiment shows the validity of algorithm.