The main classification and basic structure of the swit […]
The main classification and basic structure of the switch
1. Main classification
Classified by purpose: swing switch, band switch, record and playback switch, power switch, preselection switch, limit switch, control switch, transfer switch, isolating switch, travel switch, wall switch, smart fire switch, etc.
According to the structure classification: micro switch, rocker switch, toggle switch, toggle switch, push button switch, key switch, as well as fashionable membrane switch and point switch.
Classified according to contact type: Switches can be divided into three types: a-type contacts, b-type contacts, and c-type contacts. The contact type refers to the relationship between the operating condition and the state of the contact "after operating (pressing) the switch, the contact is closed". It is necessary to select the appropriate contact type switch according to the application.
According to the number of switches: single control switch, dual control switch, multi-control switch, dimmer switch, speed switch, splash box, doorbell switch, sensor switch, touch switch, remote control switch, smart switch, card power switch, Yuba dedicated switch.
2. Basic structure
The simplest switch has two pieces of metal called "contacts". When the two contacts are in contact, the current forms a loop, and when the two contacts are not in contact, the current opens. When choosing contact metal, it is necessary to consider the degree of its resistance to corrosion, because most metals will form insulating oxides after oxidation, making the contact unable to work properly. The selection of contact metal also needs to consider factors such as its conductivity, hardness, mechanical strength, cost and whether it is toxic. Sometimes corrosion-resistant metal is plated on the contacts. Generally, it is plated on the contact surface of the contact to avoid affecting its performance due to oxide. Sometimes non-metallic conductive materials, such as conductive plastics, are also used on the contact surface. In addition to the contacts, there are movable parts that make the contacts conductive or non-conductive. Switches can be divided into toggle switches, key switches, rocker switches, etc. depending on the movable parts. , And the movable part can also be other types of mechanical linkage.