机械制造和机电专业专业英语期末考试总复习.docVIP

Lesson 1 The major part of a machine is the mechanical system .And the mechanical system is decomposed into mechanisms ,which can be further decomposed into mechanical components .In this sense ,the mechanical components are the fundamental elements of machinery. On the whole ,mechanical components can be classified as universal and special component .Bolts ,gear ,and chains are the typical example of the universal components ,which can be used extensively in different machines across various industrial sectors .Turbine blades ,crankshaft and aircraft propeller are the examples of the special components ,which are designed for some specific purposes . 机器的主要部分是机械系统，机械系统可以分解成机构，机构又可以进一步分解成机械零件。因此，机械零件是构成机器的基本单元。总体上来讲，机器零件可以分为通用零件和专用零件两类。螺栓、齿轮和链条是典型的通用型零件，它们广泛应用在各种工业部门的不同机器上。涡轮机的叶片、曲轴和飞机的螺旋桨属于专用零件，它们具有一些特殊用途。 Machinery design is either to formulate an engineering plan for the satisfaction of a specified need or to solve an engineering problem. 机械设计用以阐明满足某种特殊需要的工程计划或解决具体的工程问题。 Provides an introduction to the design process,problem formulation ,safety factors. 提供设计过程、计算公式及相应的安全设计指标。 Reviews the material properties and static and dynamic loading analysis ,including beam ,vibration and impact loading . 提供材料特性、静态和动态载荷分析，包括梁、振动和冲击载荷。 Lesson 2 A mechanism is the members combination more than two or two connections with the members to realize the regulation motion made up by way of the activity .They are the component of machinery .Activity connections between members that have the relative motion are called the motion pairs .All motion pairs contact with planes are called lower pairs and all motion pairs contact with points or lines are called high pairs.~~~~~~The independent parameter (coordinate number) essential for description or definite mechanism motion is called the free degree of mechanism. 机构是两个或两个以上的构件通过活动联接以实现规定运动的构建组合，是机械的组成部分。两个有相对运动的构件间活动连接称为运动副。其中凡以面接触的运动副称为低副，凡以点或线接触的运动副称为高副。~~~~~~~描述或确定机构的运动所必须的独立参变量（坐标数）称为机构自由度。 The motion specific property of mechan