• The tire
• /
• s.96
• /
• pp.38-40
• /
• 1981

세계의 자동차용 타이어업계는 "확대"냐 "철퇴"냐 하는 두갈래 길에 놓여있다. 과거 세계적으로 손꼽히던 큰 타이어 메이커로는 미국의 Goodyear, Firestone, Goodrich, Uniroyal ,General의 5대 메이커와 프랑스의 Michelin, 또 영국ㆍ이탈리아의 Dunlop-Pirelli 연합이었다. 그러나 73년과 78년의 2회에 걸친 석유파동을 겪은 후, 각사의 타이어 사업에 대한 계획이 첫째, 끝까지 주요생산품종으로 사업을 계속 확대한다. 둘째, 점차 타이어로부터 철퇴한다는 두 방향으로 흐르고 있다. Radial 타이어의 생산대비지연에다 세계적인 불황이 겹쳐 철퇴하는 방향을 택하고 있는 기업이 나타나고 있으므로 세계적으로 타이어 시장이 재편성 되는 실정에 있다.<편집자주>

• The tire
• /
• s.110
• /
• pp.31-41
• /
• 1984

세계경제는 1970년대에 시작된 인플레인션과 두 차례에 걸친 석유파동 및 주요국들의 대폭적인 재정적자 등 3대과제를 안고 있는 세계적인 동시불황을 겪고 있으나, 최근에는 구미를 중심으로 점차 그것을 벗어나고 있는 것으로 보인다. 이러한 시점에서 세계의 자동차 타이어수요는 매우 어려운 환경에 직면해 있다. 즉①주요국의 자동차사업의 저조,②70년대부터의 Radial화의 급속한 증가, ③2차에 걸친 석유파동, ④유가의 상승,⑤자동차 주행거리의 감소 등 여러가지 영향으로 자동차 타이어 수요는 세계적으로 감소추세에 있다.본고는 일본 자동차타이어 협회에서 이와같은 현황하에서 앞으로의 세계 자동차 타이어 산업은 어떻게 전개되어 갈 것인지 그 전망에 대해서 객관적으로 분석한 것을 요약정리한 것이다.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.20 no.1
• /
• pp.1-13
• /
• 1996

The measurement of radial directional natural frequency ina passenger car tire rotating under the load is studied. In order to obtain theoretical matural frequency and mode shape, the ploane vibration of a tire is modeled to that of circular beam. By esing the Tieking method based on Hamiltons's principle, theoretical results are determined by considering tension horce due to tire inflation pressure, retational velocity and tangential, radial stiffness. Radial directional modal parameters varying with the inflation pressure, load, rotational velocity are experimentally determined by using frequency response function method. The results show that experimental conditions canbe considered as the parameters which shift the natural frequency.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.10 no.5
• /
• pp.724-734
• /
• 1986

The dynamic characteristics of a passenger radial tire were studied by the analytical method and the experiments. The purpose of this study is to obtain the natural frequencies and the mode shapes of a 2 ply steel belt radial tire fixed on the wheel in order to give datum of the dynamic design of tire. The governing equations are derived with the energy method. The composite toroidal finite elements with three degrees of freedom at each node are defined by specifying geometry, internal displacement functions, strain displacement and stress displacement relationships. In order to verify the capability of the present analysis, the natural frequencies and mode shapes of the passenger radial tire are obtained experimentally by using the multi-channel F.F.T. analyser and compared the numerically obtained values. The results show that the analytically obtained values are in good agreement with the experiment and in addition they are in line with the Pott's experimental results.

• The tire
• /
• s.103
• /
• pp.22-25
• /
• 1982

Radial화의 지연으로 미국시장을 Michelin, Bridgestone등에 잠식당한 Goodyear는 이제 미국시장을 회복시키기 위한 반격태세를 취하고 있다고 "Business Week"지에서 보도하였다. 그리고 동 리포트에 의하면 Goodyear, Michelin, Bridgestone 의 삼파전은 앞으로도 점차 격화되어 각사의 이익은 오히려 저하될 것이라고 분석하고 있다.<편자주>

• Journal of the korean Society of Automotive Engineers
• /
• v.15 no.2
• /
• pp.76-83
• /
• 1993

The vibration characteristics of radial tire are studied. In order to obtain theoretical natural frequency and mode shape, the plane vibration of a tire is modeled to that of circular beam. By using the Tielking method based on Hamilton's principle, theoretical results are determined by considering tension force due to tire inflation pressure, rotational velocity and tangential, radial stiffness. Modal parameters varying the inflation pressure are determined experimentally by using the transfer function method. Results show that material property and wear are parameter for shifting of natural frequency and damping.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.11 no.4
• /
• pp.125-134
• /
• 2003

In this study, Mooney-Rivlin 1st model and Mooney-Rivlin 3rd model are adopted as strain energy density functions of the rubber compounds of a radial tire. It is shown that the FE analysis using Mooney-Rivlin models for rubber compounds may provide good approximations by employing the appropriate strain range of experimental stress-strain data in a way to describe the stress-strain relationship accurately. Especially, Mooney-Rivlin 3rd model gives an accurate stress-strain relationship regardless of the fitting strain range used within the strain of 100%. The static nonlinear FE analysis of a tire inflation is performed by employing an axisymmetric model, which shows that the outside shapes of the tire before and after inflating the tire agree well with those of the real tire. Additionally, the deformations at crown center and turning point on sidewall, distribution of belt cord force, interlaminar shear strain are predicted in terms of variation of belt cord angle which is known as the most influential factor in inflation behavior of a tire.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.16 no.3
• /
• pp.102-110
• /
• 2008

It is well known that the acoustic cavity inside the tire-wheel assembly contributes to vehicle interior noise and ride comfort. In this paper, we performed acoustic and structural modal testings by varying the temperature ranging from $20^{\circ}\;to\;45^{\circ}C$ to investigate the effects of temperature on acoustic cavity resonance and structural vibration characteristics for unloaded and loaded tires. The testing has given us some findings, which are reported in this paper.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.27 no.10
• /
• pp.1667-1675
• /
• 2003

This paper has considered the calculation of lateral stiffness of radial tire's sidewall, which consists of cord stiffness and rubber sheet stiffness, by using the material constants of rubber compounds of tire. We have suggested and illustrated how to calculate the rubber sheet lateral stiffness by considering the following aspects. First, the rubber sheet consists of various kinds of rubber compounds with different thickness along the sidewall in the radial direction. Secondly, equivalent Young's modulus of the rubber sheet can be calculated by using available experimental data of rubber compounds. The present method enables us to divide the calculation domain as many as we want, which can reduce numerical error in the calculation of geometrical and mechanical properties. We have illustrated the calculation by using the data of the radial tire for passenger car of P205/60R15.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.17 no.10
• /
• pp.2426-2436
• /
• 1993

Vibration characteristics of a tire play an important role to judge a ride conformability and sound quality for a passenger car. In this study, the experimental investigation for the sound radiation of a radial tire has been examined. Based on the sound intensity techniques, the sound pressure field and the sound radiation are measured. It turns out that air pressure in tire, tread patterns, and aspect ratio of the tire govern the sound radiation characteristics. Then a numerical analysis for the tire element is conducted. During analysis, the tire element is modelled as an elastic ring. The comparison shows that the numerical output correlates to the experimental data.