There are many types of push button switches, which can be divided into ordinary push-button type, mushroom head type, self-locking type, self-resetting type, rotary handle type, with indicator light type, illuminated symbol type and key type, etc. Buttons, i buttons and different combinations. Generally, it adopts a hydroponic structure, which is composed of a button cap, a return spring, a static contact, a moving contact, and a housing. It is usually made into a composite type. There are a pair of normally closed contacts and normally open contacts. Some products can pass The series connection of multiple components increases the number of contact pairs. There is also a self-sustaining button, which can be automatically maintained in the closed position after being pressed, and can only be opened after power is turned off.
When the button is not pressed, the moving contact is connected with the static contact above. This pair of contacts is called normally closed contact. At this time, the moving contact is disconnected from the static contact below. This pair of contacts is called normally open contact: when the button is pressed, the normally closed contact is opened and the normally open contact is closed; when the button is released, the The original working state is restored under the action of the return spring.
(1) The button should be checked frequently to remove the dirt on it. Due to the small distance between the contacts of the button, when used for many years or the seal is not good, dust or oil emulsions of various stages will flow in, which will cause a reduction in insulation or even a short circuit accident. In this case, it must be insulated and cleaned, and corresponding sealing measures must be taken.
(2) When the button is used in high-temperature occasions, it is easy to deform and age the plastic, causing the button to loosen, and causing short circuits between the connection screws. According to the situation, you can add a fastening ring for tightening during installation, and you can also add an insulating plastic tube at the wiring screw to prevent loosening.
(3) The button with the indicator lamp is difficult to replace the lamp due to the deformation of the plastic lampshade due to the heat of the lamp. Therefore, it should not be used in the place where the power is on for a long time; if you want to use it, you can appropriately reduce the voltage of the bulb and extend its service life.
(4) If poor contact is found, the cause should be identified: if the contact surface is damaged, it can be trimmed with a fine file; if the contact surface has dirt or soot, it should be wiped clean with a clean cotton cloth moistened with a solvent; If it fails, it should be replaced; if the contact is severely burned, the product should be replaced.