Micro Switch Definition
A micro switch has a small contact interval and a snap-action mechanism and uses a specified stroke and a specified force to perform switching operations. It is a switch that covered by a shell and has a drive rod outside. Because of the small contact distance, we not only call it a micro switch but also call it a sensitive switch or snap action switch.
The micro switch is composed of 5 major types of constituent elements. The contact distance is small and the torque is large, which is the most obvious characteristic of the switch. Generally, there is a drive rod outside.
Micro Switch Working Principle
The external mechanical force acts on the leaf spring through the transmission elements, such as press pins, buttons, levers, rollers, etc. When the leaf spring is displaced to the critical point, then the end of the spring leaf and the fixed contact point will turn on or off quickly. And, when the force on the transmission element is removed, the spring leaf produces a reverse action force to push it back. Then the reverse action complete.
5 Way to classify microswitch on the market
There are many types and internal structures of micro switches. So we need to learn how to classify.
Firstly, People can divide into ordinary, small, and ultra-small from the volume. Generally, the size is under 27.8mm(L), 10.3mm(W), and 15.9(H) is the mini type. The size is in 19.8mm(L), 6.4mm(W),10.2mm(H) is the sub-mini type. And the size is in 12.8mm(L), 5.8mm(W), 6.5mm(W) is ultra-miniature micro switch types. Yes, they just your reference.
Secondly, if according to the protection performance, there are waterproof microswitch, dustproof, and explosion-proof;
Thirdly, if according to the breaking type, there are Single type, double type, multi-connected type.
Fourthly, according to the breaking capacity, there are also have ordinary type, direct current type, microcurrent type, and large current type according to for options.
Fifthly, on the basis of it’s working environment, the switches have ordinary, heat-resistant (250℃), and heat-resistant ceramic type.
Finally, the other classification method such as lever type, waterproof level, and so on.
The Application for Snap Action Switch
It has been widely in electronic equipment, instrumentation, mining, power systems, household appliances, electrical equipment, as well as aerospace, aviation, ships, missiles, tanks and other military fields. Although the switch is a small parts of machinery, it really pay a very important role in the system.
Usually, the different applications have different requirements for the switch. For example, the mechanical life is from 30000 to 10000000 cycles which can fit for different applications.
Such as a computer mouse, car mouse, automotive electronic products, communication equipment, military products, testing equipment, gas water heaters, gas stoves, small household appliances, microwave ovens, rice cookers, floating ball equipment, medical equipment, building automation, electric Tools and general electrical and radio equipment, 24-hour timers, etc.
The Brands of Micro Switch Compay
As we all know, the Honeywell, Omron, Marquardt, Cherry, Panasonic, Burgess, and so on. In China, the leading brand of microswitches is Zing Ear and Toneluck. Zing Ear has been established in 1983 and Toneluck in 1973, and have a lot of experience with Micro Switch R&D. So the quality of these 2 brands is good enough for you.