What is a Micro Switch : Working & Its Applications

A micro switch, also known as a miniature snap-action switch, is a type of electrical switch that operates through a quick and precise mechanism. It consists of various components that enable it to change its state when subjected to an external force. Here's how a micro switch works and some of its applications:

### Working of a Micro Switch:

1. Components:

  - Actuator/Lever: This is the part of the switch that receives external force or motion. It could be a button, lever, roller, or any other mechanism that activates the switch.

  - Spring Mechanism: Inside the switch, a spring provides tension or force against the actuator. This spring enables the switch to return to its original state once the external force is removed.

  - Contacts: These are the electrical contacts within the switch that either open or close to complete or interrupt an electrical circuit.

2. Operation:

  - In the resting state, the contacts within the micro switch are positioned to maintain a specific circuit configuration (either open or closed) based on the switch's design.

  - When an external force is applied to the actuator (such as pressing a button or moving a lever), it displaces the actuator inside the switch. This movement causes the internal spring to compress or release.

  - The change in the spring's tension triggers the movement of the electrical contacts. In a normally open switch, the contacts close to complete an electrical circuit; in a normally closed switch, the contacts open, interrupting the circuit.

  - Upon releasing the external force, the spring mechanism inside the micro switch returns the actuator to its original position, restoring the contacts to their initial state before activation.

### Applications of Micro Switches:

1. Appliances: Used in various household appliances like microwave ovens, washing machines, refrigerators, and dishwashers for controlling functions such as door locking, limit sensing, and cycle control.

2. Automotive Industry: Found in automotive applications such as brake light switches, door switches, seat position sensors, and automatic window controls.

3. Industrial Equipment: Widely used in industrial machinery for limit sensing, safety switches, control systems, and automation equipment due to their reliability and quick response.

4. Electronics: Incorporated into electronic devices and gadgets for push-button switches, control panels, keyboards, and safety switches.

5. Medical Devices: Utilized in medical equipment for patient monitoring, equipment controls, and safety mechanisms.

6. Aerospace: Found in aerospace applications for sensing and controlling functions in aircraft systems.

Micro switches are valued for their compact size, precision, reliability, and ability to operate in various environments, making them suitable for a wide range of applications across industries where precise and dependable switching is required.