缺点： ① 制造和安装精度要求较高； ②不适宜用于两轴间距离较大的传动

一、棘轮机构的工作原理 二、棘轮机构的类型、特点和应用

1、定轴轮系：齿轮系传动过程中，其各齿轮的轴线 相对于机架的位置都是固定不变的

连杆机构 由低副（转动副、移动副、球面副、圆柱副、及螺旋副等）联结而成的机构。或称低副机构

一.研究机构的组成及机构运动简图的画法 二.了解机构具有确定运动的条件 三.研究机构的组成原理及结构分类

1.本章研究的内容及目的 2.机械运转的三个阶段

第二章 1.自由度的计算 高副 低副 复合铰链 虚约束局部自由度 2.瞬心 相对瞬心 绝对瞬心 瞬心的数目 三心定理

Pre-Class Work Gifted Children: those who possess some quality or innate ability which has been recognized and identified by number of testing and observation devices and who manifest interest and success in either physical, intellectual, or artistic pursuits

Lottery ticket: It is the numbered ticket sold at face value so that when the winning number is announced, the one with the corresponding ticket claims a reward Do you or the people you know buy the lottery ticket?

Detailed studies of unit 8 L1 Seen from the space. When our planet is seen from space L4. average n.平均数;平均标准Tom' s work is above/ below/ about up to the average