Teacher Courses

42 year

UNITED ARAB EMIRATES

The most common switch action is a hybrid of the cam and snap actions. The pseudo-snap-action switch is a cam action switch with a snap action actuator. This type of switch has a number of attributes that make it an attractive solution for many applications. The simplicity of the design provides relatively low manufacturing costs, minimized contact bounce, fast open/close cycle, and excellent tactile feedback. Figure 4-12 shows a pseudo-snap action switch mechanism. Take notice that the contact and actuator design is very similar to the cam action shown in Figure 4-10. The principal difference is the actuator ball and spring, that are intended to provide the snap action. A specialized type of pseudo-snap action switch is the drum switch. These switches are generally designed to provide a forward-off-reverse function for low horsepower, three phase motors. Figure 4-13 shows a typical commercial drum switch.