Membrane switch is an operating system that integrates button functions, indicating elements, and instrument panels. It consists of four parts: panel, upper circuit, isolation layer and lower circuit. When the membrane switch is pressed, the contacts of the upper circuit are deformed downwards and are in contact with the plates of the lower circuit. After the finger is released, the contacts of the upper circuit bounce back, the circuit is disconnected, and the circuit triggers a signal. Membrane switch has rigorous structure, beautiful appearance and good sealing performance. It has the characteristics of moisture resistance and long service life. Widely used in electronic communication, electronic measuring instruments, industrial control, medical equipment, automobile industry, smart toys, household appliances and other fields.
1. The quality of the finished membrane switch button should be checked from the aspects of material, shape, circuit part, insulation, jumper, mechanical performance and other aspects.
1.1. Materials: Substrate, silver paste, carbon ink, spacer, adhesive, adhesive, reinforcement board, and insulation printing should meet the requirements of the drawings.
1.2. Shape: The shape, conductor line, insulation treatment, liner combination, etc. shall comply with the drawings or provide physical samples.
1.3. In terms of appearance, combined state: the surface must not have residual material shavings, foreign matter, stains, bumps, grease attached to the surface and inside, fingerprints on the circuit, and burrs on the punched shape.
1.4. Scars: All lines and contacts must not have cuts running through the surface (that is, the cuts are cut from the line to the substrate). Slight scratches are also in principle not to affect its resistance. The surface of carbon ink is very prone to scratches, and the scratches should not affect the conduction of the circuit as a criterion.
1.5. Foreign matter: the line must not have any foreign matter attached to it.
1.6. Line part, conductor thickness: Generally, the conductor thickness is controlled at 7-12μm, and it should be uniform and smooth. Defects and pinholes: judged according to the following graphic standards, one is allowed within each 50mm range.
1.7. Carbon ink: The carbon ink covering the silver paste circuit should ensure that the silver paste is completely covered, its thickness is 8-12μm, and there must be no obvious silver paste protrusion. Break and short circuit: No break or short circuit of the conductor is allowed.
1.8. Insulation printing: All membrane switch contact points must not have any insulation ink attached. The surface of the insulating ink should be flat to avoid any defects such as bubbles or pinholes that will affect the insulation effect. Adhesion strength: After the insulating ink is dried, put the ink surfaces against each other and press heavily for 24 hours to ensure that the insulation does not stick to each other. Use a pressure-sensitive tape to stick it with hand pressure without air bubbles for 1 minute, then peel it off quickly, and no ink will fall off.
1.9. Jumper: All jumper parts are in accordance with the requirements of line conductors, and all jumper products must pass 100% open, short-circuit and insulation resistance tests. Make sure there is no open, short circuit and insulation resistance should be greater than 500MΩ (500VDC for 1 minute).
1.10. Dimensions of stamping burr and die extrusion: The size of stamping burr and extrusion should not be greater than 0.2mm, and the position should be towards the side without conductors. Position offset of the upper and lower lines: The allowable tolerance for the center position offset of each switch contact of the upper and lower lines is ±0.5mm.
2. Membrane switch is an intelligent energy switch device that is very different from ordinary traditional switches. Its material and appearance are very sensitive and require very careful care and preservation. The bubble film of the membrane switch must not be torn off easily, because it is an important part to protect the button. Similarly, there are many details that are as important as this, so Puzzle Technology has to remind everyone to pay attention to the membrane switch. Storage preservation.
2.1. The bubble film lined between the membrane switch and the membrane switch is to reduce the pressure of the button and prevent failure, so it should be kept.
2.2. The transparent film on the front and back of the membrane switch protects its display window, so don't tear it off easily.
2.3. After taking out some of the film panels, they should be tied up as they are, but they must not be tied too tightly.
2.4. Film surface stickers and membrane switches that have a hand feel and a large quantity need to be packed and placed vertically to prevent the keys from being invalidated by long-term heavy pressing.
2.5. The outgoing wires of the membrane switch should be well protected and cannot be placed downwards.
2.6. Membrane switches with display windows must prevent the material from being bent by force when handling and placing them, which will leave creases.
2.7. Membrane switches are stored indoors at room temperature, and should be dust-proof and moisture-proof. There is no acid, alkali or other corrosive gases in the surrounding air.
The above summarizes the precautions for quality inspection and storage of membrane switch keys. Customers are welcome to come to our company for consultation and guidance. All employees of the company will provide you with excellent product services. Let us all seek common development together!
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