第二章 平面连杆机构(国外英文资料).docVIP

第二章 平面连杆机构(国外英文资料) The second chapter plane linkage mechanism Case introduction: through the radar antenna, automobile wiper, mixer and other practical application of the mechanism analysis, the introduction of the concept of four rod mechanism, introduced the four bar mechanism of the composition, basic form and working characteristics. Section 1 hinged four bar linkage First, the structure and basic form of the hinge four bar mechanism 1. hinged four bar mechanism As shown in Figure 1-14, four bar linkage mechanism is composed of a closed system and four bar connecting components of the rotating pair, and one of the members is fixed. The fixed piece 4 is called a frame, and the two components 1 and 3 directly hinged with the frame are called connecting rods, and the component 2 which is not directly connected with the frame is called a connecting rod. The connecting rod, if it can make a full circle movement, is called a crank, otherwise it is called a rocker. 2. types of hinged four bar mechanisms The hinge four bar mechanism can be divided into three basic forms, the crank rocker mechanism, the double crank mechanism and the double rocker mechanism, according to the different motion forms of the two connecting rods. (1) crank rocker mechanism. In a hinged four bar mechanism, the mechanism is called a crank rocker mechanism if there is a full cycle movement of the connecting rod and the swing of the other swing bar. As shown in Figure 2-1 is a diagram of the crank rocker mechanism, principle of radar antenna adjustment mechanism. The mechanism is composed of AB, BC, component is fixedly connected with the antenna and CD frame composed of DA, AB can be used as a component to rotate, the whole circle of a crank; the other 3 antenna as the mechanism for rack bar can be a range of swing. As with the crank rocker; slowly, antenna elevation change. As shown in Figure 2-2, the car wiper, as the motor with a crank AB rotation, wiper glue and rocker CD swing together, com