At present, the application of technology in the world is increasing day by day. As enterprises and public departments try to control costs and provide customers with better experience, the trend of technology application is increasing in many indoor and outdoor public places.

This approach brings many benefits, but it also creates a series of challenges. This includes the human machine interface (HMI), which is usually composed of a series of push switches. Generally speaking, we will take good care of our own equipment, but these public equipment are likely to be abused maliciously or unintentionally.

To this end, designers can now use extremely rugged switches to develop various man-machine interfaces for public technology, so that it can stand the test of time.

What key specifications should designers consider when specifying switches for rugged man-machine interfaces.

We need tamper proof switches

Fundamentally, in order to realize the system application, the system needs users to input information to determine the operation they want to achieve, or provide information to the system. Because speech recognition technology is still in the early stage of development, the use of various types of switches is still the preferred method for man-machine interface development.

When technical equipment is deployed in an uncontrolled area and operated by non equipment owners, it is likely to be abused. Individual users sometimes choose to maliciously destroy the equipment for a variety of reasons. Even legitimate users of the equipment may not cherish the equipment. They will press the switch carelessly and vigorously, so as to shorten the service life of equipment, especially technical equipment with man-machine interface. It is obvious that, for example, a precise membrane based switching matrix can not be used for a long time in the above cases.

As the deployment of such equipment increases, the demand for high-strength man-machine interface also increases. In addition to family life, almost everything we do in our daily life is inseparable from all kinds of push switch control systems.

For example, when you go somewhere by bus, you will see that the fuel pump in the gas station is usually equipped with a button to select the gasoline product number. In the case of electric vehicles, you will find that the charging station also has several buttons for entering commands and starting / stopping the charging process. Button based HMI equipment is required when inflating tires, cleaning or cleaning our car at the service station.

Even if we travel by train instead of driving, we will see more and more kinds of buttons; For example, buttons are used when opening doors, going to the bathroom or using intercom equipment. When buying tickets, the ticket machine may also be equipped with a rugged man-machine interface.

After arriving at the destination, we may need some cash. At this time, you will find that the ATM is also equipped with a high-strength keyboard to effectively prevent damage. The building we are going to may also be equipped with access control or intercom system. After entering the building, there is also a button in the elevator room to select the floor.

High strength man-machine interface special switch

The high-strength man-machine interface special switch (which can withstand the destructive operation of rough users or malicious saboteurs) is different from the standard switch in terms of manufacturing materials and methods.

Vandal resistant switches are usually of metal structure, and stainless steel is the most used, but nickel plated (Ni) brass is also common, and anodic aluminum oxide is sometimes used. After properly sealed, these switches can prevent moisture intrusion caused by weather or water intrusion into the system caused by unintentional (or malicious) water splashing on the HMI panel. The protection level of man-machine interface can usually reach IP67, that is, the switch can be completely unaffected by dust and can be soaked in water at a depth of 3 feet for 30 minutes.

Similar to the IP rating scale for entrance protection, the IK rating scale defines the level of impact protection. The protection grade of most anti-destructive switches can reach ik10 (the highest impact protection grade at present), and the maximum energy level that can withstand impact can reach 20 joules.

Many anti damage switches are provided with icons on the buttons for function indication; In many cases, operation feedback is provided through LED lamps under weak light conditions.

Metal waterproof is a damage proof sealed push switch, which can provide standard LED lighting in the main body with a diameter of 8mm / 12mm / 16mm / 19mm / 22mm / 25mm / 30mm. This series of switches are made of stainless steel and protected by anti scratch starter. The rated service life of the switch is 500000 switching operations, which is suitable for use under the environmental conditions of 20 ° C ~ + 55 ° C. The switch adopts SPDT and DPDT forms, and is equipped with normally open or normally closed contacts, with instantaneous or locking action function.

The stainless steel actuator can adopt flat, dome or strip structure, and the corresponding specifications can be designed according to the application. The required starting force of the switch is 2.5n (SP) or 3.5N (DP) - it needs a clear pressing action to operate, and can bring positive tactile feedback to the user.

The switch meets the sealing protection requirements of IP67 and can withstand the mechanical impact of ik10 grade. Its threaded structure can be easily assembled through the front panel. At the same time, the cross line function is used to realize the easy connection with the printed circuit board.