• 한국산학기술학회논문지
• /
• 제14권6호
• /
• pp.2581-2587
• /
• 2013

철도차량의 안전성을 위해 사용되는 윤축은 차량 전체 중량의 16%를 차지하는 요소로서, 철도차량의 경량화에 있어 필수적으로 연구되는 대상이다. 본 연구는 기존 윤축의 중량을 요구강도에 만족시킴과 경량화를 목적으로 창의적 문제해결이론인 TRIZ의 6SC를 적용하여 중공구조의 윤축 내부에 사용될 수 있는 캡을 설계하였고, 설계에 대한 검증을 위해 해석 툴인 ANSYS를 활용하였다. 본 연구에서 제안한 캡의 재질은 SM45C이며 중공구조이다. 또한, 윤축에 요구되는 강도를 만족하기 위해 중공 윤축의 베어링 시트 부 내부에 위치한다. 본 연구를 통해 설계 및 해석된 캡을 삽입한 윤축은 전동차의 윤축에 요구되는 기준을 만족하였으며 무게는 중실축과 비교하였을 때, 약 6.75%를 감소시켰다. 윤축 강도에 대한 평가 기준은 EN13103 및 EN13104의 규격을 적용하였다. 또한, 캡을 장착한 윤축의 최대응력 및 중량에 대해 기존의 중실축, 중공축과 비교함으로써 설계에 대한 효과를 검증하였다.

• 한국기계가공학회지
• /
• 제17권4호
• /
• pp.32-38
• /
• 2018

In this study, the one-piece propeller shaft composed of carbon/epoxy was designed and manufactured for 4 wheel drive automobiles that can bear the target torsional torque performance of 3.5kN.m. For the CFRP tube, braiding machine was used to weaving carbon fiber and it was formed the braided yarns with the braid angle ${\pm}45^{\circ}$ and axial yarns to improve strength of the lengthwise direction. The final CFRP tube of propeller shaft was evaluated through the torsional torque test. The CFRP propeller shaft satisfied requirement of the target torsional maximum torque of 3.5kN.m. Also, it was found that the one-piece composite propeller shaft with CFRP tube had 30% weight saving effect compared with a two-piece steel propeller shaft.

• 한국복합재료학회:학술대회논문집
• /
• 한국복합재료학회 1999년도 추계학술발표대회 논문집
• /
• pp.49-52
• /
• 1999

Substituting composite structures for conventional metallic structures has many advantages because of higher specific stiffness and specific strength of composite materials. In this work, one-piece propeller shafts composed of carbon/epoxy composite and glass/epoxy one were designed and manufactured for a rear wheel drive automobile, which uses generally a steel two-piece propeller shaft. From the tests of the composite propeller shafts, it was found that the propeller shafts satisfied requirements of static torque transmission capability, torsional buckling capability and the first natural bending frequency and had 40% weight saving effect compared with steel propeller shaft.

• 유공압시스템학회논문집
• /
• 제6권3호
• /
• pp.23-31
• /
• 2009

Counter shaft transmission is a popular automatic transmission power train in construction vehicles such as wheel loader and forklift. The gear train layout of counter shaft transmission is a very basic and important development stage because it affects the most of components design including hydraulic system and shift control algorithm, etc. This paper presents a design methodology for the gear train layout from the analysis of power flow path and clutch hook-up of the existing counter shaft transmission that is adopted in commercialized construction vehicles. Also, independent constraints for the meshed gear ratios are derived in order to realize forward 4-speed and reverse 3-speed gear ratio. The layout design principle proposed here was applied to the new original counter shaft transmission that is underdevelopment.

• Tribology and Lubricants
• /
• 제29권6호
• /
• pp.397-402
• /
• 2013

This study examined the tribological characteristics of the drive shaft and axle system in vehicles. The first drive shaft example contained end play for a CV joint that transferred part of the transmission power to the wheel. The joint part of the drive shaft was deformed because of reduced durability due to wear. Thus, vibrations caused the body to shake and become unbalanced when the drive shaft transferred the power. The second example was the cross-section of a shaft that connected the slip-connection of the propeller shaft on the input side to the yoke flange of the output side; the durability was reduced because of corrosion. End play caused by wear between the bearing and cross-section shaft appeared to cause shaking. In the third example, a grease leak reduced lubrication and thus caused damage to the hub bearing and inside the knuckle. The failure was produced by sticking. The fourth example had noise produced by the gear and gear transfer. This was due to the backlash of the pinion and few ring gears for the differential gear. Therefore, drive shaft and axle systems must be thoroughly checked and managed to minimize and reduce failure phenomena.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2001년도 ICCAS
• /
• pp.89.2-89
• /
• 2001

Wheel chair bound persons need assistance since there are many steps or curbs or other obstacles blocking their path in the roadways and walkways. Although a step may be small, it may be very difficult for such a person to climb over it. Therefore, we are proposing a power assist wheel chair robot that enables a wheel chair bound person to climb over steps up to about 10 centimeters in height without assistance from others. By using the proposed wheel chair robot, a user can maintain inverse pendulum control after raising its front wheels Then, a user can move forward to the step maintaining the inverse pendulum control, and can climb over the step using motor force of a rear wheel shaft ...

• 한국생산제조학회지
• /
• 제7권5호
• /
• pp.29-37
• /
• 1998

In recent years, grinding techniques for precision machining of stainless steel used in shaft, screw parts and clear value have been improved by using the superabrasive wheel and precision grinding machine. The completion of optimum dressing of superabrasive wheel makes possible the effective precision grinding of stainless steel. However, the present dressing system cannot have control of optimum dressing of the superabrasive wheel. In this study, a new system and the grinding mechanism of optimum in-process dressing of superabrasive wheel. Therefore, the optimum in-process electrolytic dressing is a good method to obtain the efficiency and mirror-like grinding of stainless steel (STS304)

• 한국융합학회논문지
• /
• 제9권8호
• /
• pp.179-184
• /
• 2018

자동차의 구동방식은 전륜구동, 후륜구동, 4륜구동의 방식이 있다. 구동방식에서 운전자가 원하는 방향으로 전환하는 것과 바퀴에 동력을 전달하여 구동하는 두 가지의 역할을 수행하는데 있어 가장 중요한 부품이 등속 조인트이다. 도로상에서 주행 시에는 노면의 상태에 따라서 동력을 전달하는 부품들에 충격이 가해질 수 있다. 본 연구에서는 각각 샤프트의 길이가 다른 3개의 등속 조인트 각 모델들은 CATIA로 모델링하였고 ANSYS를 이용하여 구조 및 피로해석을 수행하였다. 본 연구 결과로는 Model 2가 다른 모델 대비 뛰어난 내구성을 가짐을 알 수 있었다. 이러한 결과를 이용하여 충격에 대한 내구성을 가지는 등속 조인트 설계를 할 때에 유용한 자료가 될 것이라고 사료되며, 등속 조인트의 디자인을 융합기술에 접목하여 미적 감각을 나타낼 수 있다.

• Tribology and Lubricants
• /
• 제34권6호
• /
• pp.325-331
• /
• 2018

Automobiles and systems requiring high gear ratios and high power densities generally use worm gears. In particular, as worm gears have a small volume and self-locking function, home appliances such as refrigerators and washers consist of worm gears. We can classify worm gears into cylindrical worms and rectangular worms. According to the AGMA standard, there are four types of cylindrical worms, ZA, ZN, ZK and ZI, depending on the machining of the worm shaft. It is preferable to use a ZI-type worm shaft, which is a combination of a worm wheel having an involute helical tooth surface and a conjugate tooth surface. However, in many cases, industries mostly use ZK, ZN, and ZA worm shafts because of the ease of processing. This paper presents numerical approaches to produce ZI and ZA worm surfaces and worm wheel. For the analysis of the transmission error of a worm gear system, this study (1) generates surface profile functions of ZI profile worm gear and worm shaft based on the common rack theory, (2) adopts the Newton-Raphson method for the analysis of the gear surface contact condition, and (3) presents and compares the corresponding transmission errors of ZI and ZA worm gears.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2003년도 춘계학술대회논문집
• /
• pp.342-352
• /
• 2003

Idle NVH characteristics are one of the most important aspects among the vehicle performances. Vehicle developers are devoted to improve vehicle interior noise and steering wheel and seat vibrations. In order to improve the idle quality, noise and vibration transfer path should be carefully evaluated. Also, effects of various components related to the idle performance should be confirmed. A general procedure for improving the idle qualify is described in detail. The relationship among cylinder pressure characteristics, crankshaft rotational speed variation, and vehicle vibrations is also investigated. Influences of drive shaft, torque converter, air conditioning system, vehicle structure including engine mount system, and idle control parameters on the vehicle idle quality are studied. Weak points of typical vehicles on the idle qualify are identified. Some of improvement measures are proposed and verified.