Tactile switch is an electronic switch that can be triggered by a gentle touch or press. Its design and functionality make it an important control interface and user interaction tool in modern electronic devices. These switches not only provide a convenient control mode, but also adapt to the needs of various devices through their sensitive touch response and multi-functional design.

1. Meaning

Tactile switch also known as button switch, first appeared in Japan [called: sensitive switch] when used to meet the conditions of the operating force of the switch operation direction pressure switch function closed, when the pressure is disconnected, its internal structure is based on the change of metal shrapnel force to achieve the switch.

2. Structure

The Tactile switch is divided into two categories: the metal spring as the switch of the light contact plate, small contact resistance, and 20 mn cluster. Feel good, have a "tick-off" crisp sound. The switch habit of using a conductive rubber as a contact path is called a conductive rubber switch. The switch feels good, but the contact resistance is large, generally in 100 to 300n. The structure of the Tactile switch is to move the button down to make the contact reed or conductive rubber block contact the welding pad, forming a path.

The operating force of the Tactile switch is related to the state of the reed. The starting force is directly proportional to the compression distance of the reed when the reed is compressed to 5. % 170% of the operation force suddenly reduced, accompanied by a "tick" sound. Turtle rubber switch generally has two structures. The operating force curve varies greatly depending on the geometry of the rubber block.

3. Classification

● Sealed direct plug type Tactile switch: using sealing structure, the pin is straight plug type, so it is sealed direct plug type Tactile switch. The dustproof, waterproof ability is very strong. In the air conditioning, washing machines and other home appliances are widely used.

● LED high insulation resistance Tactile switch: the circuit has a light-emitting diode, and its insulation resistance is more than 1000 MΩ, so it is an LED high insulation resistance Tactile switch. Widely used in digital audio and video use.

● Ultra long life flat Tactile switch: life up to 1 million times, the actuator is standard flat, so it is super long life flat Tactile switch. Its contacts are made of stainless steel silver plating material, which reduces the connection resistance and greatly enhances the connection reliability. Suitable for industrial machinery processing machine tool operation plate, home appliances and equipment application.

● Short trip patch Tactile switch: actuator travel only. 15 + / -.05mm, the pin is a patch type, so it is a short stroke patch type Tactile switch. Its short travel span also determines its high service life of 200,000 times. Widely used on-board equipment, such as car anti-theft remote control and so on.

● Horizontal operation type direct plug Tactile switch: the actuator is on the side, and the pin is straight plug type, so it is horizontal operation type direct plug Tactile switch. Four pins, two of which are fixed and grounded, and the other two are contact through terminals. It is widely used in communication equipment.

● Double action key single knife double throw Tactile switch: there is double actuator, the contact is single knife double throw, so it is double action key single knife double throw. Its insulation resistance is up to 1,000 MΩ, and it is widely used in on-board equipment.

● Iofilateral standard Tactile switch: the surface shape is square, and the actuator is standard on the top surface, so it is equilateral standard Tactile switch. There are many kinds of such Tactile switches, such as 6.0 * 6.0,12.0 * 12.0,6.2 * 6.2,5.2 * 5.2,4.9 * 4.9,7.2 * 7.2, etc. In addition, they have patch (SMD) and direct plug (DIP). Suitable for a variety of operating panels, a wide range of applications.

● Ultra-thin patch type Tactile switch: its pin is patch type, and the height is only 0.8mm, so it is ultra-thin patch type Tactile switch. Its ultra-thin characteristics, determine that it is suitable for high-density installation.

4. Use

Color TV set, black and white TV set, audio equipment, video recorder, video camera, computer, game machine, fax machine, intercom, baton, machine tool control device, copy, printer, electronic instruments, instruments and other household appliances.

● Mechanical behavior:

    ● Operating force: 1N,1.6N,2.5N;

    ● Eltility; (internal control);

    ● Switch life: 300,000,500,000,1 million.

● Behaviour of electricity:

    ● Contact resistance: 100m Ω (actual <20m Ω);

    ● Jitter time: 5ms (actual <1ms);

    ● Electrical switch life: 300,000 times, 500,000 times, 1 million times.

5. Packaging type

6. Choose the methods

The key factors affecting the quality of the touch switch are the protection, weldability, reliability, life, hand feel, production process and installation size of the touch switch.

First for the pin base, touch switch pin substrate for brass or phosphorus copper (low grade for iron), to reduce the contact resistance, pin basically silver plating treatment, for silver in air SO2 gas oxidation, directly affect the switch weldability and contact resistance, so high quality touch switch first in the base of silver plating thickness and silver plating process control in place.

The second key influencing factor of conduction reliability is the structure of the contact point, because the function of the Tactile switch is that the contact point and the shrapnel contact conduction, so the larger the contact surface of the contact point, the better, the contact surface is determined by the structure. There are about three types of structures in the market.

The third life and feel is determined by the travel of the Tactile switch and the shrapnel. The shorter the trip, the lighter the sound, the longer the life, the longer the travel, in the case of fixed shrapnel process, mainly depends on the stroke or sound determines the life of the Tactile switch;

In addition, the key factor that determines the life of shrapnel is stamping technology. The stamping technology of Japan and Taiwan has been very popular in China, so in the case of technical improvement, the requirements for imported materials are reduced.

The fourth is the production process, with the accessories eventually affect the quality is assembly process, assembly process depends on the production company's management ability, staff quality consciousness and quality assurance ability, different guarantee ability of the final product quality must be different, market assembly method has artificial and machine, assembly of the machine cost is low but low product quality, artificial assembly cost is high but high quality.

Fifth is the factory inspection, factory inspection method and project also affect the quality of the final touch switch, such as appearance, feel, conduction, resistance is sampling or inspection, such as some companies requirements scrap rate is PPM or zero defect, after the factory inspection set sampling inspection or quality inspection process.

7. Compare the differences

We compare from the following aspects of Tactile switch mainly include: stamping- -injection molding- -cleaning- -assembly-molding- -inspection process; and the film switch process is mainly: screen printing- -die-cutting- -assembly-detection process. Both of them have high requirements on the production environment. Relatively speaking, the higher the dust prevention level of the workshop production, the more guaranteed the quality of the product. Film switch requires high precision, requires accurate coordination of each part, the appearance of the product, color is also very picky. The Tactile switch requires a higher degree of precision, because the coordination of the parts directly affects the product description and feel, the performance of the product is very high, but the appearance of the product, color is not as picky as the film switch.

The cost and price of Tactile switch are relatively low, without large price adjustment due to the market fluctuation of raw materials; while the film switch has relatively high price and large volume, which is greatly affected by the raw material price factor. Tactile switch and film switch are belong to the functional switch, Tactile switch is used gently press the switch button to make the switch, when the hand can be disconnected, its internal structure is by the metal shrapnel force bounce to achieve on and off. Thin film switch is a kind of itself with line button, usually the top is composed of PET or PC and so on material of text or pattern panel, the lower is conductive line, the middle layer is analog switch form and isolation effect of PET material of double-sided tape, the lowest part is usually PET material contact and connection line. When pressing the key part of the surface with a finger, the key contact contacts the corresponding part of the lower part to form a current connection.

The touch switch is small, standard parts, size and related parameters must be industry standard, the color is relatively single, and the film switch can be different sizes, appearance and color, according to the requirements of the guest, more convenient and flexible. Soft film switch, closed structure and waterproof structure, better adaptability to the environment. Tactile switch can not produce function independently, must be used with PCB circuit board to form a complete open control system, and the film switch is the panel, switch, conductive line integrated, can independently form a complete control system, can provide customers with an whole switch solution.