The Component That Makes Your Machine ‘click’

What are micro switches?

Miniature snap-action switches (or micro switches as they are frequently called) are simple but novel electrical switches that are found in almost all electrical appliances ranging from residential to industrial purposes. The interesting feature about them is that they require the application of very little physical force to switch. This happens because they make use of a “tipping-over” or “over-center mechanism”, wherein the switch flicks into a suitable position automatically depending on which side of the centerline it has crossed into.

Features of micro switches

Micro switches have a variety of features that make them immensely useful in various sectors requiring automation. Essentially, their application is to be used in a control circuit. What it does, is that depending upon the information received and sensed by the switch via the control circuit, it detects changes in its surroundings, which act as stimuli for its operation.

It makes use of two helical springs along with an actuator for its mechanism. This arrangement of two springs along with an actuator leads to its defining feature of a tactile click and crisp feel upon being switched.

This arrangement of the springs also allows for a small movement in the actuator to produce a large movement in the electrical contacts via the use of the spring which further accelerates the motion already produced by the actuator.

But, why do you need them?

Micro switches are maybe the only thing after the human brain that can learn, adapt, and be of use in any kind of situation, here the situation being all machines and circuit systems.

Mainly, they are of great utility in two situations- firstly, when there is only availability or suitability of low operating force, but a definite action has to be done.

Secondly, and perhaps, most importantly, they serve their purpose where long term reliability is needed. Since their arrangement leads to the independence of the closing force on the switch contacts from the operating force, this contact force, which is always sufficient and never too much, promotes long life.

Applications and Uses

Micro switches are used in a variety of electrical appliances, ranging from as small as a gas stove to as large as the convertible top of an automobile. The basic versions are used in ice makers, ovens, electric hot water faucets, etc. while there are also waterproof versions used in lawnmowers and coffee machines.

There are also automotive versions of switches. These automotive micro switches are heavily used in automotive intelligent control circuits. Some examples being in automotive door locks (such as in car doors, which go on to close fully, after applying a little bit of physical force), automotive inverters, shifters, etc.

Some rated switches are used to control the current in a circuit, which is highly convenient for controlling small electronic devices such as lamps, solenoids, and motors.

Low-force versions are used in vending machines which can sense the input of a coin in the machine. In this case, especially the long-term life and reliability of these switches comes in handy, as thousands of coins are pushed into the vending machine during its working life.

Now that we have learned about the huge contribution of micro switches in making life so easy for us and making this world the awesome place that it is, you would surely be looking into getting your hands onto some of these micro switches for your business.