The main components of a microswitch are the shrapnel, the contact, the moving arm, the case, etc. The shrapnel is the core component of the microswitch. Shrapnel is the core component of the microswitch, it is a kind of metal sheet with elasticity, which can be deformed under the action of external force to drive the contact to open and close. The contact is the output part of the microswitch, which is a metal sheet with conductivity that can be contacted or separated from the fixed contact under the push of the shrapnel, thus realizing the opening and closing of the circuit. The moving arm is the input part of the microswitch, which is a rotatable rod or lever that can apply force to the shrapnel by means of external transmission elements (e.g. push buttons, wheels, etc.), thus triggering the action of the microswitch. The case is the protection part of the microswitch, it is a kind of shell made of plastic or metal, which can fix and isolate the internal parts of the microswitch, preventing the influence of dust, moisture, mechanical shock, etc. on the microswitch.
The working principle of the microswitch is to use external force to compress or stretch the shrapnel, so that its displacement to the critical point to produce instantaneous action, so that the dynamic contact and fixed contact quickly connected or disconnected. When the external force is removed, the shrapnel is restored to its original state, and the contacts are then restored to their original state, closing the circuit. The design of the shrapnel of a microswitch is very important, and different shapes and materials of shrapnel can be designed according to different needs. Micro switches have small contact spacing, short action stroke, small pressing force, and rapid on-off. The speed of action of its moving contacts is independent of the speed of action of the transmission element.
Applications of microswitches
Microswitches can play different roles such as connecting, disconnecting and transforming in the process of signal transmission, and are widely used in the fields of electronics, machinery, instrumentation, automobiles, home appliances and so on. For example, in an intelligent door lock control system, the microswitch can detect the state of the door lock and send a signal when the door lock is opened or closed, thus realizing the control of the state of the door lock. In a rice cooker, the microswitch detects the switching of the lid and controls the heating or keeping warm function when the lid is opened or closed. In a computer mouse, the microswitch can detect the mouse buttons and send signals when the buttons are pressed or released, thus realizing the operation of the mouse. These are typical applications of microswitches.
Advantages of microswitches
The advantages of micro switches are as follows:
Simple structure, low manufacturing cost and easy maintenance.
Sensitive operation, reliable action, fast response and long life.
High adaptability, can work in different environment, temperature, humidity, pressure and other conditions.
High flexibility, can be designed according to different needs of different forms, specifications, parameters of the micro switch.
High safety, can prevent the occurrence of electrical failure, fire, explosion and other dangerous situations.
Disadvantages of microswitches
The disadvantages of micro switches are as follows:
The contacts are easy to wear, resulting in poor contact and affecting the quality of the output signal.
The contacts are easy to oxidize and vulcanize, resulting in increased contact resistance and affecting the output current.
Contacts are easy to generate arc, resulting in increased contact temperature, affecting the performance of the contact material.
Contacts are easily affected by mechanical vibration and impact, resulting in misoperation or failure.
Improvement of microswitches
In order to overcome the shortcomings of microswitches, people have made continuous improvements to microswitches, mainly in the following areas:
Optimize the material, shape, size and gap of the contacts to improve the wear resistance, corrosion resistance, temperature resistance and arc resistance of the contacts.
Increase the number, form and combination of contacts to improve contact reliability, output stability, output diversity, etc.
Increase the protection device, isolation device, filtering device, etc., to improve the anti-interference, anti-noise, anti-overvoltage contacts.
Increase the sensing device, display device, control device, etc., to improve the intelligence, visualization, automation, etc. of the contact.
Micro switch is a simple and practical electrical switch, its principle is to use the deformation of the shrapnel to drive the opening and closing of the contacts, its application is to play a different role in the process of signal transmission, such as connecting, disconnecting, transforming, etc., its advantages are simple structure, sensitive operation, adaptable, flexible, high security, its disadvantages are that contacts are easy to wear and tear, oxidation, arcing, subject to vibration, impact. Its improvement is to optimize the performance of the contact, increase the function of the contact, increase the protection, isolation, filtering, sensing, display, control and other devices. Micro switch is a small but important electrical components, it has a wide range of applications in various fields, it is worthwhile to understand and master.