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电动助力转向器的设计与三维建模
摘 要
由于动力转向系统具有转向操纵灵活、轻便、并可吸收路面对前轮产生的冲击等优点，自20世纪50年代以来在各国汽车上开始普遍应用。现今液压助力转向器(HPS)是以内燃机作为动力的汽车助力转向器的主流。但是传统的HPS需要持续的能量消耗，降低了汽车的燃油经济性。同时其复杂的液压系统具有助力特性不可调整、污染环境、维修不便等缺点。相比之下，20世纪80年代开始研究的汽车上的电能为动力的电动助力转向系统(EPS)除具有传统液压助力转向系统(IiPS)的优点外，还具有助力大小可调、路感可调、环保、耗能低、维护方便等优点，因此自20世纪80年代以来世界著名汽车厂商纷纷开始研究开发EPS，并取得了很大的进展。
首先,对EPS进行了概述;其次,阐述了EPS的总体结构和工作原理,同时也详细介绍了各个部件的作用及其原理;然后,对CATIA三维软件的建摸过程进行了较详细的介绍;最后谈到了EPS的试验规范问题.

关键词：汽车 电动 转向器


Abstract
Because of the advantages such as the steering sensitivity,handiness, and absorbability of the impulse from the road the power steering system is widely used since 1950's. Now the Hydraulic Powering Steering (HPS) is still mainly used in the automobile drived internal-combustion engine. But it also needs the continuing consume of fuel to keep pump running so it reduces the economy of fuel .And its complex hydraulic system pollutes the environment,makes the repairing difficult and the features couldn't be adjusted conveniently. Compared with HPS, the Electric Powering Steering system (EPS) has its special characters, such as the adjustable features, environment-friendly, energy saving and convenient maintenance, so it is developed quickly since some world famous automotive companies begin to research the EPS powering steering in 1980's.
The overall structure and working principle of the EPS was briefly described.Meanwhile,it detailed the function and principles of the all of every components; thirdly,the procession of mould buiding for three-dimensional software for CATIA;At the end,what standarded the test of EPS was speaken.

Key word: Auto Electric power Diverter