Standard Specification for Quality Inspection of Membrane Switches

The quality inspection of membrane switches is a very important task. The first task of a successful membrane switch manufacturer is to establish a complete quality assurance system.

In the quality inspection of the membrane switch, in addition to paying attention to the color rendering of the ink that workers are very familiar with and the color reproducibility required by customers, it is more important to pay attention to the inherent quality of the membrane switch. Such as key operation force, life, peel strength, and high temperature, low temperature, constant temperature and humidity, test indicator for return line cathode, insulated cathode and withstand voltage. The following 4 are the standard specifications for quality inspection of membrane switches. Let's take a look together.

1. Technical requirements for membrane switch testing

Appearance quality inclusions, stain inclusions are less than 2 /dm². The length of inclusions and stains should not exceed 1mm. No accumulation is allowed, with at least 50mm scratches. The scratch is less than 1/dm², the length of the scratch is not more than 20MM, and the depth and width are not more than 50um; scratches with a depth not exceeding 1um are allowed.

2. The color detected by the membrane switch

The color of the same batch of products should have no obvious difference, the color printing layer should have sufficient hiding power, and the color and structure below cannot be clearly seen by the reflected light. When printing a transparent ink layer, the double-color overlap should not exceed 1mm, and the color deviation caused by it should be allowed; the edges of printed characters and color blocks should not exceed 0.15mm.

3. The size of membrane switch detection

The size of the membrane switch should meet the requirements. The parallelism and perpendicularity of the two adjacent sides of the membrane switch design shall meet the requirements. The center distance between adjacent wires at the end of the lead tape is usually 2.54 mm.

4. Peel strength detected by membrane switch

The peel strength of each adhesive layer of the membrane switch should not be less than 8N/25mm.

Relevant Blog

Film switch type
January 22, 2020Membrane switch is an operating system which integrates key function, indicating element and instrument panel. It consists of panel, upper circuit, isolation layer and lower circuit. In order to touch...view
Advantages of Capacitive Touch Panel
February 24, 2021Capacitive touch panel technology uses the body's sense of electricity to work. The capacitive touch panel is composed of a composite glass screen. The interlayer and inner surface of the glass sc...view
Detailed Information about Touch Panel
February 2, 2021The touch panel is also called touch screen. Any electronic device that you see, which can realize human-computer interaction basically uses touch screen technology and touch panel. It enables a simpl...view
Have You Neglected The Design Of Solder Pad In PCB Board Design?
April 8, 2020When designing PCB pad in PCB board design, it is necessary to design in strict accordance with relevant requirements and standards. Because in SMT chip processing, the design of PCB pads is very impo...view
Wiring Arrangement And Reasonable Layout Of PCB Board
April 3, 2020Wiring arrangement and reasonable layout of components on PCB board(1) No crossover circuit is allowed in the printed circuit on PCB board. For wires that may be crossed, two methods of "drilling...view
Why Can Touch Screen Layers Control PLC?
December 30, 2020The PLC itself is controlled by changing the state variables such as control register D, input port X, soft relay state M, and time relay T, so as long as the state of these variables can be modified,...view