Four Methods to Repair Membrane Keypads

Four Methods to Repair Membrane Keypads

Membrane Keypads, also known as control panels or Membrane switches, are widely used in intelligent instruments and meters, medical equipment, household appliances such as microwave ovens, soy milk makers, washing machines, etc. In some cases, the cost of Membrane keypads accounts for a smaller proportion of the entire product, and when it needs to be repaired, the transportation fee back and forth plus labor costs often exceed the cost of buying a new one, thus losing the value of repair. However, in certain situations, timely repairs of damaged film keys can bring significant convenience. The following is an explanation of how to repair Membrane keypads:

(1) From a technical perspective, replacing the Membrane keypads is not a complex operation. First, disassemble the membrane panel and peel off the top layer of Membrane keypads. Use a multimeter to identify the connection points between each Membrane keypad and the circuit board to ensure that the switch connections after modification correspond correctly with the original ones.

(2) Positioning cones are used to drill positioning holes in the metal plate at each switching point of the lower layer film. The size of the drilled holes should be slightly larger than the practical size of the miniature Membrane keypad column to ensure that the miniature switch key column can move up and down freely within the hole without obstruction. If the holes are too small, it will affect the elastic effect of the switch and cause the Membrane keypads to malfunction.

(3) Carefully compare the distance between each small hole on the golden-month board, fix the microswitch to the printed circuit board, and connect the corresponding connection points for each switch according to the connection points. Also, leave a corresponding edge of the printed circuit board based on the actual spatial position between the metal plate and the display board to fix the switch board. Since the new switch board is located between the metal plate and the indicator light display board, it is necessary to drill holes in the printed circuit board that correspond to the positions of the indicator lights on the display board to ensure that the luminous tubes of the display board pass through the printed circuit board and can be seen from the panel to display the signal. At the same time, there should be a certain gap between the lines and between the two boards to prevent short circuits.

(4) Insert the prepared printed switch board into the small holes corresponding to each Membrane keypad and metal plate, ensuring that the top of the keypad column is parallel to the metal surface. If it protrudes too high above the board surface, the outer panel film will press down on the switch after restoration and make it unusable; if it's too low, pressing with your hand may not activate the switch properly, causing it to malfunction. After inserting the broken switch board, use an adhesive pad to flatten it for use. Adhere the adhesive to the metal plate, then restore the outer layer protective film of the panel to its original state. The modification process is complete. The modified switch board has a very good tactile feel during operation, producing a clear clicking sound when pressed, giving a direct sense of the switch being turned on or off! It has a long service life, high reliability, easy maintenance, and if any switch fails during use, you can directly determine which one by listening to the clicking sound of the spring when pressing the button. Simply replace it!

In summary, these are the four methods for repairing Membrane keypads. For more information, please continue to follow our website, where we will update content from time to time.