• 한국정밀공학회지
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• 제25권6호
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• pp.108-115
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• 2008

The wear on engine valve and seat insert is one of the most important factors affecting engine performance. The engine valve and seat insert must be able to withstand the severe environment that is created by: high temperature exhaust gases generated while the engine is running, rapid movement of the valve spring, high pressure generated in the explosive process. In order to study such problems, a simulator has been developed to generate and control high temperatures and various speeds during motion. The wear simulator is considered to be a valid simulation of the engine valve and seat insert wear process with various speeds during engine activity. This work focused on the test of various degrees of wear on four different exhaust valve materials such as HRV40, HRV40-FNV (face nitrided valve), STL #32, STL #6,. Throughout all tests performed in this study, the outer surface temperature of the seat insert was controlled at $350^{\circ}C$, the cycle number was $4.0{\times}10^6$, the test load was 6860 N, the fuel was LPG the test speed was 20 Hz (2400 RPM) and the seat insert material was HVS1-2. The mean (standard deviation) maximum roughness of the exhaust valve and seat insert was $25.44\;(3.16)\;{\mu}m$ and $27.53\;(3.60)\;{\mu}m$ at the HRV40, $21.58\;(2.38)\;{\mu}m$ and $25.94\;(3.07)\;{\mu}m$ at the HRV40-FNV, $36.73\;(8.98)\;{\mu}m$ and $61.38\;(7.84)\;{\mu}m$ at the STL #32, $73.64\;(23.80)\;{\mu}m$ and $60.80\;(13.49)\;{\mu}m$ at the STL #6, respectively. It was discovered that the maximum roughness of exhaust valve was lower as the high temperature hardness of the valve material was higher under the same test conditions such as temperature, test speed, cycle number, test load and seat insert material. The set of the HRV40-FNV exhaust valve and the HVS1-2 seat insert showed the best wear resistance.

• 한국자동차공학회논문집
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• 제8권1호
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• pp.172-182
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• 2000

A hybrid type automotive drivers seat was invented with new concepts for the reduction of weight and manufacturing costs. Fundamental studies were performed to determine the basic geometry of reinforcing support. A prototypical design was provided by the manufacturer considering compatibility with other parts. Several structural analyses simulating various crash situations were performed and modifications were continued until a final design was reached. A sample product was manufactured and sled crash tests were performed to verify the safety of the seat. Comparisons of test results with the previous model and a seat from another company proved safety performances to be superior.

• 한국기계가공학회지
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• 제16권6호
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• pp.47-54
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• 2017

This study analyzed air suspension seat frame structure and vibration for 50 - 180 kg mass driver to obtain optimum seat design parameter values for the equivalent spring constant and damping coefficient. Various air suspension seat frames were designed following WTS-003 and KS B 6839 standards, and then evaluated using finite elements analysis. Resonance and vibration tests were performed according to the 78/764/EEC standard.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(III)
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• pp.49-58
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• 2003

In this paper, the structural strengths of a rolling stock seat were numerically evaluated under several design load conditions based on the UIC requirements. The rolling stock seat was designed for the high speed train of a Chinese conventional line. To maximize its weight reduction and structural strength, some aluminium alloys like 6N01-T5 and ALDC8-T5 were applied to the base frame, side frame and armrest. The designed seat frame satisfied the strength requirements on inertia loads due to accelerations, and fatigue test conditions. However, it violated the requirements on the static test of UIC 566 OR. Some design modifications were suggested and numerically evaluated to satisfy the static test requirements.

• 한국산학기술학회논문지
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• 제13권12호
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• pp.5689-5695
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• 2012

본 연구에서는 차량에 적용되는 시트 재질인 폴리우레탄 폼의 점탄성 특성을 고려하여 시트와 인체의 진동특성을 시험 및 수치해석 방법을 이용하여 분석하였다. 압축 시험을 통해 폴리우레탄 폼의 점탄성 특성인 비선형성과 준-정역학적 특성을 구하였다. 또한 컨벌루션 적분법 및 비선형 강성 모델을 이용하여 폴리우레탄 폼의 점탄성 특성을 수학적으로 모델링하였다. 시트의 승차감 기여도를 분석하기 위하여 시트의 동역학 모델과 ISO5982의 표준 인체 수직진동 모델을 이용하여 수직 진동모델을 구성하고 관련 운동방정식을 유도하였다. 비선형 운동방정식은 Runge-Kutta 적분법을 이용하여 수치해석 시뮬레이션을 수행하였다. 철도차량의 차체 바닥에서 측정한 진동가속도 입력에 대한 시트와 인체의 응답 특성을 분석하고 시트 설계 파라미터에 대한 승차감 지수 값들의 변화를 분석하여 시트 설계에 대한 방법론을 제시하고자 한다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.103-104
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• 2006

Wear of valve seating face and seat insert seating face influence the performance of engine, so they are important. To manufacture good quality valve and seat insert which have wear resistance the relations between wear factors and wear of the two seating faces have to be inspected. Cycle number is one of the important wear factors wearing the two seating faces and it can translate into mileage in rear car. But little is blown. Test variable is only cycle number and the cycle numbers are $2.0{\times}10^6,\;4.0{\times}10^6\;6.0{\times}10^6,\;8.0{\times}10^6$. And the other test conditions were fixed. Rmax of valve seating face and seat insert seating face increase linearly as cycle number is increased. Rmax of valve seating face were smaller than seat insert seating face in each cycle number. Reaction production by tribological reaction and sliding wear was found on the two faces.

• 재활복지공학회논문지
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• 제8권3호
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• pp.151-160
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• 2014

본 연구에서는 기존의 시/청각 방식의 운전정보 전달체계의 한계를 극복하고 더불어 교통약자들의 운전수행에 도움이 되는 자동차용 햅틱 시트 기술을 개발하고자 하였다. 이를 위해 동전형 모터 30개를 사용한 진동자극용 시트커버형 시제품과 모터드라이버모듈을 제작하였고 65세 이상의 고령 피험자들을 대상으로 실시한 가상운전상황에서의 시트진동자극에 대한 실험에서는 피험자들의 전체 진동인지 점수 평균은 3.5/4점으로 87.5%의 인지율을 보여주었다. 또한 모든 피험자가 4번의 과속경고신호를 모두 인지하는 결과를 보여주었다. Trail Making Test 점수에 따른 그룹별 진동인지점수에 대한 통계분석 결과 유의한 차이가 발견되지 않았고 시각기능과 인지기능이 저하된 고령자라도 진동을 인지하는 촉각기능은 동등한 능력을 보여주는 결과를 얻었으며 이 결과는 고령운전자에 대한 차량 내에서의 시트를 통한 진동자극의 운전정보 유용성을 보여주는 것으로 사료된다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.1195-1196
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• 2011

• 한국산학기술학회논문지
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• 제14권1호
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• pp.39-44
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• 2013

자동차 부품 중 승차감이나 안전에 직접적으로 관련된 부분은 시트이다. 또한 이러한 여건을 만족시키면서 승객의 안전을 보장하는 충분한 강성과 강도를 가져야 한다. 자동차 시트는 3D 모델링 되었고, 전후 유격, 측면 유격 및 전후 모멘트 강도의 3가지 실험에 대하여 시뮬레이션으로서 구조해석을 하였다. 해석 결과, 전후 유격 시험에서는 $0.038^{\circ}$의 변형 각도의 값과 측면 유격 시험에서는 $0.04^{\circ}$의 변형 각도의 값이 각각 나타났다. 또한 전후 모멘트 강도시험에서는 전방 및 후방 하중 시에 최대의 전변형량 값이 각각 0.18946mm 및 3.2482mm로 나타났다. 본 연구결과는 자동차 시트 프레임의 과도한 변형 및 파괴가 없음으로서 승객의 안전을 보장하는 충분한 강성과 강도를 검증할 수 있었다.

• 자동차안전학회지
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• 제7권3호
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• pp.7-13
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• 2015

Occupant protection performance in frontal crashes has been developed and assessed for mainly front seat occupants over many years, and in recent years protection of rear seat occupants has also been extensively discussed. Unlike the front seats, the rear seats are often occupied by children seated in rear-facing or forward - facing child restraint systems, or booster seats. In the ENCAP, child occupant protection assessments using 18-month-old(P1.5) and 3-year-old(P3) test dummies in the rear seat have already been changed to new type of 18-month-old (Q1.5)and 3-year-old(Q3) test dummies. In addition, ENCAP are scheduled with the development and introduction of test dummies of 6-year-old (Q6) and 10.5-year-old children(Q10) starting 2016. In KNCAP, Q6 and Q10 child dummies will be introduced in 2017 as well. Automobile manufacturers need to develop safety performance for new child dummies closely. In this paper, we focused on Q6 and Q10 child dummies sitting in child restraint system. Offset frontal crash tests were conducted using two types of test dummies, Q6 and Q10 child dummies, positioned in the rear seat. Q6 and Q10 were used to compare dummy kinematics in rear seating positions between Q6 behind the driver's seat and Q10 behind the front passenger's seat. The full vehicle sled test results of both dummies were conducted with different restraint systems. It showed that several injury and image data was collected as the result of the full vehicle sled test. Based on the results of these investigations, this paper describes which factor is most important and combination is the best performance when evaluating rear seat occupant protection for Q6 and Q10 child dummies.