Automotive Transmission Rattle:Root Causes to Innovative Solutions

汽车变速箱异响：创新解决方案的根本原因

• 批准号: EP/D050332/1
• 负责人: Homayoon Rahnejat
• 金额: $ 25.81万
• 依托单位: Loughborough University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2006
• 资助国家: 英国
• 起止时间: 2006 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FD050332%2F1
• 关键词: Automotive; Transmission; Rattle; Root; Causes

In recent years, significant improvements in vehicle handling and engine noise reduction, together with the growing use of lighter materials in powertrain components have led to the emergence of a plethora of Noise, Vibration and Harshness (NVH) concerns, establishing them as indicators of vehicle quality with direct impact on sales (J. D. Power & Associates Reviews). The cost to industry of meeting customers' NVH expectations is in the order of tens of millions of Pound, whilst warranty claims may further increase the total cost. Transmission gear rattle is now recognised by manufacturers and customers as the number one target for NVH improvement, following the continuous development of engines with higher cylinder compression ratios.Transmission rattle is the result of repetitive impacts between lubricated surfaces in the presence of backlash at the meshing gear teeth, under various loaded or unloaded conditions. Engine torque fluctuations due to combustion and the inertial forces, together with the dynamic response of the complete system result in vibration of the lightly loaded components in the gearbox, such as the idler gears, synchronizer rings and sliding sleeves. Transmission of vibration from the gear shafts through bearings to the gearbox housing is the principal mechanism, radiating noise to the environment. Current vehicle design trends towards lighter flywheels and lower idling speeds increase the prominence of gear rattle as a major noise source.Lack of understanding of the complex interactions between the drivetrain system and its constituent components and industry's need for timely solutions have resulted in costly palliative methods. The common characteristic of all these quick fixes , late in the design process, has been their application-specific nature. Therefore, these approaches do not follow a root-cause, sustainable system method.The proposed research introduces a holistic, wide-ranging and fundamental numerical and experimental study of the drivetrain system, focusing on the gear rattle root cause identification, with emphasis on the effect of lubricated gear meshing surfaces. The development of virtual prototypes, simulating system behaviour will result in sustainable solutions for attenuation of rattle, assisting car manufacturers in their primary target of reducing time to market. The approach proposed here aims to bring a powerful competitive advantage to the UK automotive industry and its supplier base by following a preventive approach to achieve significant cost-savings.

近年来，车辆操控性和发动机降噪方面的重大改进，以及动力总成部件中越来越多地使用更轻的材料，导致了大量噪音、振动和粗糙度（NVH）问题的出现，使其成为直接影响销售的车辆质量指标（j.d. Power & Associates评论）。为了满足客户对NVH的期望，行业的成本约为数千万英镑，而保修索赔可能会进一步增加总成本。如今，随着更高气缸压缩比的发动机不断发展，制造商和客户已将变速器齿轮振动视为改善NVH的首要目标。在各种加载或卸载条件下，啮合齿轮齿侧隙存在时，润滑表面之间的重复冲击是传动颤振的结果。由于燃烧和惯性力引起的发动机扭矩波动，加上整个系统的动态响应，导致变速箱中轻载荷部件（如惰轮、同步环和滑套）的振动。振动从齿轮轴通过轴承传递到齿轮箱外壳是主要的机制，向环境辐射噪音。当前的汽车设计趋向于更轻的飞轮和更低的空转速度，这增加了齿轮嘎嘎声作为主要噪声源的重要性。由于缺乏对动力传动系统及其组成部件之间复杂相互作用的理解，以及行业对及时解决方案的需求，导致了成本高昂的缓和方法。在设计过程的后期，所有这些快速修复的共同特点是它们具有特定于应用程序的性质。因此，这些方法不遵循根本原因，可持续的系统方法。本研究对传动系统进行了全面、广泛和基础的数值和实验研究，重点研究了齿轮颤振的根本原因识别，重点研究了润滑齿轮啮合面对颤振的影响。虚拟原型的开发，模拟系统的行为将产生可持续的解决方案，以减少震动，帮助汽车制造商缩短上市时间的主要目标。这里提出的方法旨在通过以下预防性方法实现显著的成本节约，为英国汽车工业及其供应商基础带来强大的竞争优势。

项目成果

An investigation of manual transmission drive rattle

• DOI: 10.1243/14644193jmbd232
• 发表时间: 2010-06
• 期刊: Proceedings of the Institution of Mechanical Engineers, Part K: Journal of Multi-body Dynamics
• 作者: M. Cruz;S. Theodossiades;H. Rahnejat

Multi-body dynamics in vehicle engineering

• DOI: 10.1177/14644193231181666
• 发表时间: 2023-06
• 期刊: Proceedings of the Institution of Mechanical Engineers, Part K: Journal of Multi-body Dynamics
• 作者: H. Rahnejat;P. Johns-Rahnejat;N. Dolatabadi;R. Rahmani

The Effect of Thermo-Hydrodynamics on Manual Automotive Transmissions Gear Rattle

热流体力学对手动汽车变速箱齿轮嘎嘎声的影响

• DOI: 10.1115/detc2009-87226
• 发表时间: 2009
• 作者: De La Cruz M

Elastodynamic response of automotive transmissions to impact induced vibrations

汽车变速器对冲击引起的振动的弹性动力响应

• 作者: Malika Perera (Author)

Tribology and Dynamics of Engine and Powertrain: Fundamentals, Applications and Future Trends

发动机和动力总成的摩擦学和动力学：基础知识、应用和未来趋势

• 发表时间: 2010
• 作者: Rahnejat, H.