Coil Spring의 設計條件과 疲勞破壞에 對한 硏究

丁太權,朴昌彦,沈在基,梁仁榮 조선대학교 생산기술연구소 1980 生産技術硏究 Vol.1980 No.-

The material selections and strength fomula of coil springs were used to calculate the design-stress. The surface treatment, such as shot peening, coating and chemical treatment, improved anti-corrosion and anti-fatigues. And then the fatigue-fractures generated by the kinds of cause in using coil spring so that we intended to prevent from ones. Also we achived that the optimum design model was decided by design condition of hot coil spring.

교정용 CLOSED COIL SPRING의 기계적 성질에 관한 비교 연구

강창은,김상철 원광대학교 생체재료·매식연구소 1998 원광생체재료·매식 Vol.7 No.2

Closed coil springs have been used in many different ways for orthodontic tooth movement. Space closure using closed coil spring has more advantage than that with any other elastic materials. Spring properties could be alloy types, wire diameters, lumen sizes and spring lengths. The study was undertaken to compare the pattern of force decay of three alloy types of closed coil spring made of stainless-steel(SS), cobalt-chrome-nickel(Co-Cr-Ni) and nickel-titanium(NiTi), and to provide load-deflection curves of closed springs of various lumen sizes and alloy types. The results were as follows ; 1. Closed coil springs showed a 7-14% force decay in 4 weeks and the stainless-steel spring showed relatively higher force decay as compared with the Co-Cr-Ni, NiTi I and Ⅱ springs. 2. The major force decay occurred in the first 24 hours for stainless-steel and NiTi springs. 3. When the lumen size of closed coil spring was increased, its stiffness was decreased. And stainless-steel spring was significantly stiffer than NiTi spring.

Coil Spring & Viscous Damper System의 동특성분석

김민규,전영선 한국지진공학회 2007 한국지진공학회논문집 Vol.11 No.2

본 연구에서는 Coil Spring과 Viscous Damper 시스템의 동특성 분석을 위한 특성실험을 수행하였다. Coil Spring과 Viscous Damper 시스템은 원자력발전소 비상디젤발전기의 진동저감 및 지진력 저감을 위한 장치로 선정되었다. Viscous Damper 가진 속도에 따라서 그 특성이 다르게 나타나기 때문에 그 영향을 평가하여 진동저감과 지진력 저감효과를 동시에 고려할 수 있는 장치로서의 성능을 평가하고자 하는 것이다. 실험결과 수평방향의 경우 속도의존 비선형 거동이 두드러지게 나타나고 있는 반면 연직방향은 그러한 특성이 미미한 것으로 나타났다. 강성과 감쇠 모두 설계값보다 고평가 되고 있는 것으로 나타나서 전체 시스템의 면진 및 진동저감시 영향을 미칠 수 있는 것으로 나타났다. This paper presents the results of experimental studies of the mechanical characteristics of the Coil Spring and Viscous Damper system. The Coil Spring and Viscous Damper systems were selected for the isolation of Emergency Diesel Generator (EDG) which is located in Nuclear Power Plant (NPP). The Coil Spring and Viscous Damper systems were developed for the operating vibration isolation and seismic isolation for scaled Model EDG System. The damping properties of the viscous damper changes as the variation of velocity. Through this research nonlinear damping characteristics and the effective stiffness of coil spring and viscous damper system were evaluated.

Mass Effect Analysis of a Coil Spring for the Performance Evaluation of a Gas Insulated Circuit Breaker

이대우,손정현,유완석 한국정밀공학회 2014 International Journal of Precision Engineering and Vol. No.

Since the performance of a circuit breaker which has the spring operating mechanism mainly depends on the dynamic behavior ofa coil spring, the analysis of the dynamic behavior of a coil spring is required for a performance evaluation of a circuit breaker. Whena spring moves so fast from the releasing state, a lot of energy is used to move a self-weight of a spring. Thus, the mass effect analysisof a spring operating mechanism is required for the performance evaluation of a circuit breaker accurately. In this study, a releasetest bed is designed for evaluating the dynamic behaviors of a coil spring. Three types of spring models such as a linear spring model,a nodal spring model and a lumped parameter spring model are established for comparing the modeling error of a spring due tothe mass effect. RecurDyn is employed to carry out the computer simulation and results are compared with test results. The actualenergy transferred to the follower during high-speed motion is analyzed through the comparisons of the kinetic energy between theexperiment and the computer simulation.

승용차 복합재 코일스프링 개발을 위한 설계변수들의 결정

오성하(Sung-Ha Oh),최복록(Bok-Lok Choi) 한국기계가공학회 2013 한국기계가공학회지 Vol.12 No.1

This paper presents the feasibility on the application of composite coil spring, which has great interest in the automobile industry. In order to obtain much lighter weight of the composite spring, it will be necessary to optimize the design variables such as fiber angles and diameter of coil, etc. First of all, mechanical properties were measured to consider the effects of FVR and ply angles for carbon fiber composite material. And the shear modulus with respect to ply angles were derived based on twisting angles calculated by torsional beam model. Next we determined the design parameters of composite coil spring, which has equivalent spring rate to the steel coil spring. In order to assess the proposed method, finite element model of the composite spring was developed and analysed to obtain the spring constant. The results showed that static spring rate of the composite spring was in a good agreement with that of steel spring.

EFFECTS OF END COILS ON THE NATURAL FREQUENCY OF AUTOMOTIVE ENGINE VALVE SPRINGS

H. LIU,김도중 한국자동차공학회 2009 International journal of automotive technology Vol.10 No.4

In this paper, we present a method for estimating the natural frequencies of various engine valve springs such as constant pitch, two-step variable pitch, three-step variable pitch, and progressive springs. Since a valve spring’s surging amplitude is magnified when the spring’s natural frequency coincides with the frequency of the cam profile harmonic components, estimating the natural frequency of the spring is the first step in predicting valve spring surging phenomena. A new method for calculating the valve spring’s natural frequency is proposed in this paper that considers the end coil effect. This method predicts not only the natural frequency of a helical spring at a fixed number of active turns, but also the change in the natural frequency as the spring is compressed. The experimental results demonstrate that nonlinear characteristics of engine valve springs can be predicted from the given initial pitch curves. In this paper, we present a method for estimating the natural frequencies of various engine valve springs such as constant pitch, two-step variable pitch, three-step variable pitch, and progressive springs. Since a valve spring’s surging amplitude is magnified when the spring’s natural frequency coincides with the frequency of the cam profile harmonic components, estimating the natural frequency of the spring is the first step in predicting valve spring surging phenomena. A new method for calculating the valve spring’s natural frequency is proposed in this paper that considers the end coil effect. This method predicts not only the natural frequency of a helical spring at a fixed number of active turns, but also the change in the natural frequency as the spring is compressed. The experimental results demonstrate that nonlinear characteristics of engine valve springs can be predicted from the given initial pitch curves.

압축하중을 받는 통형 스프링의 유효 권수 결정

김유림(Yu Lim Kim),김성훈(Sung Hoon Kim),조규종(Kyu Zong Cho) 대한기계학회 2014 대한기계학회 춘추학술대회 Vol.2014 No.11

Stiffness of helical coil spring usually calculated by spring equation which is derived by Hook’s Law. In prediction of stiffness using the spring equation, the active number of helical coil spring is determined between 1 or 2 by considering the end condition simply, then the spring stiffness shows inaccurate result by contact phenomena seat and large deformation. A method to calculate active coil number is proposed in this study and it is composed of two steps. First, step is performing a compression FE analysis of the coil spring and calculating the number of active coils by investigating stress distribution of coil. In order to check the validity of the method, the method was applied to a variety of shapes and conditions of the helical coil spring, and it is concluded that the stiffness prediction using the active number calculated by suggested method shows a good agreement between the spring equation and suggested method result.

Design of end coil angular position and centerline shape of C-type side load coil spring for reducing side load of MacPherson strut suspension

Seunghyeon Cho,Hankun Yeon,Hyunho Kim,김창완 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.3

MacPherson strut suspension, which is widely used vehicle suspension type, decreases the riding comfort and durability of strut module due to the side load generated at the damper. In this study, a method for designing a C-type side load coil spring is proposed to reduce the side load, considering not only the centerline shape, but also the end coil angular position of the spring. The effect of end coil angular position as well as centerline shape on the force axis are analyzed through finite element analysis (FEA) and regression analysis. Formulas are established based on the analyses and the C-type coil spring was designed considering the effects of both design variables on the force axis. Then, the side load of the MacPherson strut suspension on which the designed C-type side load coil spring was mounted was calculated by using the flexible multibody dynamic analysis method. Finally, a side load reduction effect of C-type side load coil spring is analyzed by comparing with that of helical-type coil spring.

상악견치 후방견인시 저항원 조절을 위한 MAS(Molar Anchoring Spring)의 초기 응력분포에 관한 광탄성학적 연구

전윤식 대한치과교정학회 1996 대한치과교정학회지 Vol.26 No.4

저자는 마찰견인법으로 상악견치 후방견인시 저항원상실을 최소화하기 위해 근심경사된 구치를 직립시키는 Molar Uprighting Spring의 작용기전을 응용하고 마찰견인법의 장점을 이용하여 임상적으로 사용이 용이하며 저항원상실이나 견치의 조절되지 못한 경사이동(uncontrolled tipping)등의 부작용을 최소화 할 수 있는 장치인 Molar Anchoring Spring(MAS)을 고안하였다. MAS를 임상에 적용한 결과 비교적 만족스러운 결과를 얻어 이에 장치를 소개하며 MAS의 저항원 조절능력과 견치의 이동향상을 평가하기 위하여 광탄성 모형을 제작한 후 주호선에 diameter 0.009″ lumen size 0.030″ NiTi closed coil spring만을 장착하여 250mg의 견인력이 발생하도록 한 경우와, 같은 NiTi closed coil spring으로 동일한 견인력이 발생하도록 제작한 MAS를 제1대구치 auxiliary tube에 삽입하고 견치 전방에 걸어준 경우를 비교실험 하여 견치견인시 초기응력분포를 관찰한 결과 다음과 같은 결과를 얻었다. 1. 주호선(main arch wire)에 저항원 조절을 위한 조치없이 견치에 수평견인력만을 가했을 때 구치부에 심한 저항원상실은 물론 견치의 원심이동양상도 조절되지 못한 경사이동(uncontrolled tipping)으로 나타났다. 2. 구치부의 저항원 조절을 위해 사용한 MAS는 견치의 원심이동 초기에 구치부 저항원 조절효과와 견치의 정출없는 조절된 경사이동(controlled tipping)을 유도할 수 있는 장치로 나타났다. The efficiency of maxillary canine retraction by means of sliding mechanics along an 0.016 continuous labial arch and an 0.009 inch in diameter with a lumen of 0.030 inch NiTi closed coil spring was compared with that using the same NiTi closed coil spring and Molar Anchoring Spring(MAS) which was designed by author. MAS was made of .017″ X .025″ TMA wire and was given 60 degree tip-back bend on the wire close to the molar tube. This study was designed to investigate molar and canine root control during retraction into an extraction site with continuous arch wire system. Two techniques were tested with a continuous arch model embedded in a photoelastic resin. A photoelastic model was employed to visualize the effects of forces applied to canine and molar by two retraction mechanics. With the aid of polarized light, stresses were viewed as colored fringes. The photoelastic overview of the upper right quadrant showed that stress concentrations were observed in its photoelastic model. The obtained results were as follows. 1. Higher concentration of compression can be seen clearly at the distal curvature of the canine and mesial curvature of the molar and premolar when NiTi closed coil spring was applied only, which means severe anchorage loss of the molar and uncontrolled tipping of the canine. 2. The least level compression was presented at the mesial root area of the molar and premolar, and mesial root area of the canine when NiTi closed coil spring and MAS were used simultaneously. Especially mesial alveolar crest region of the canine was shown moderate level of compression that means MAS can be used as a appliance for anchorage control and prevention of canine extrusion and uncontrolled tipping during canine retraction.

공간곡선 벡터에 의한 원통 코일 스프링의 동적 거동 해석

김대원,김종수 한국소음진동공학회 1998 소음 진동 Vol.8 No.6

This paper addresses the results of an experimental and analytical research of a helical coil spring subjected to dynamic behavior using space curve vector after considering elongation rate. Vibrations in helical coil spring can be divided into 3 modes such as vibrations of coil spring center axis' vertical direction. axis' horizontal direction, direction about center axis. However. these 3 modes are dependent one another and are characterized as coupled. The dependency was proved through both theoretically and experimentally analyzing the results of dynamic characteristics of coil spring center axis' vertical direction vibration by transfer matrix method using the governing equation of static equilibrium. Also this paper shows that pitch angle and active coils in coil spring affect the dynamic spring characteristics of the above 3 modes and are especially sensitive to the mode for vibration of axis' horizontal direction which most affects especially on dynamo stability of helical coil spring.