Four steps to repair membrane switch keypad

(1) From a technical point of view, it is not complicated to replace the membrane switch. You can disassemble the membrane keypad panel first, peel off the first layer of button graphic overlay film above, and use a multimeter to find out each button switch point and circuit. The connection position of the board to ensure that the modified and assembled switch connection points correspond to the original ones.

(2) Tap the hole on the metal plate with a positioning cone from each switch point of the lower film. The size of the hole to be penetrated is slightly larger than the actual size of the micro switch key pillar, so as to ensure that the micro switch presses the key pillar to move up and down in the hole without being blocked. If the hole is too small, it will affect the elastic effect of the switch and make the switch key. Failure.

(3) Carefully compare the distance between each small hole on the printed board, fix the micro switch on the printed board, and connect the connection line according to the corresponding connection point of each switch. The actual space between the corresponding printed board edges is reserved to fix the switch board, because the new switch board is located between the metal plate and the indicator display board, and the printed board must also be marked with the indicator position corresponding to the display board. To ensure that the luminous tube of the display panel can see the display signal from the panel through the printed board, and there must be a certain distance between the circuit and the board to prevent short circuit.

(4) Embed the manufactured printed switch board in the corresponding small hole of each key switch and the metal plate, so that the top of the keypad post is parallel to the metal surface. If it exceeds the board surface too high, the top panel film will recover If it is too low, the switch cannot be reset or work when it is pressed by hand. Insert the broken switch board and use it with a rubber pad to use it, and stick the glue to the metal Then restore the outer protective film of the panel to its original state. The modification and assembly process is over, and the assembled switch board is modified. The operation feels very good. There is a good tactile metal dome sound when the button is pressed, giving a kind of Very
intuitive switch connection and disconnection feeling. It has a long service life, high reliability, and easy maintenance. If the key switch is broken during use, it can be judged directly by the sound of the metal dome when the keypad is pressed, and then modified, assembled and replaced.