Connector manufacturing as the second pillar industries of electronic components, its product is a kind of functional components with electrical connection properties. The main function is in the devices and components, components and cabinet, between systems and subsystems have the effect of electrical connections and signal transmission, constitute the whole circuit system is one of the basic elements of electrical connection necessary. Now, the connectors have been widely used in aerospace, military equipment, communications, computers, automobiles, industries, household appliances and other fields.
There are many kinds of electronic connectors, but the manufacturing process is basically the same. The manufacturing of connectors can generally be divided into four stages: Stamping, Plating, Molding and Assembly.
Stamping: The manufacturing process of electronic connectors generally begins with stamping pins. Through a large high-speed punching machine, the electronic connector (pin) is made of a thin metal strip. One end of the large rolled metal belt is fed into the front end of the punching machine, and the other end is wound into the winding belt wheel through the hydraulic working table of the punching machine. The metal belt is pulled out by the winding belt wheel and rolled into the finished product. Stamping is the manufacturing area of the metal terminal. As the main component of the connector, the shape and size of the metal terminal affect the subsequent process and the quality of the finished product.
There are two common types of terminals 1: Pins. 2: Terminals Suppliers typically use many different types of copper alloys to provide the best electrical and mechanical properties for terminal design.
Brass Features: 1: Zinc accounts for 5%-40% 2: Excellent elasticity, strength and electrical properties 3: The cheapest metal by mass
Phosphor bronze Features: 1: Excellent strength, toughness, and electrical conductivity 2: Very good elasticity and fatigue strength 3: Use for typical electric contact springs
Pressing requires two types of equipment: Punch and Stamping die; First, the die enters the crimping process. The crimping equipment provides the pressure, and the die cuts the terminal and shapes it. Second, the bar metal is passed into the pressing equipment and die, the metal strip may be coated or not coated. Next, the metal is cut and shaped into a joint. This is done in a small cutting and molding process as the parts pass through the mold. Finally, the finished terminal is removed from the mold and dropped into the collection box for collection. They may be rolled into tubes to enter the next process, such as coating or assembly.
Plating: Connector pin stamping should be sent to the electroplate section after completion. So - called Plating, that is, after the stamping forming metal terminal needs to be plated on the metal surface tin, lead, gold and other different coating. Plating is the process of depositing a coating with the desired form by means of a point solution method. The purpose of electroplating is generally to change surface characteristics to provide improved appearance, corrosion resistance, abrasion resistance, and other required properties, or a combination of these properties.
The contacts material of the electronic connector is generally copper alloy, commonly used coating: Gold, Silver, Tin
1:Gold has excellent conductivity, second only to copper and silver.
2:Gold is an inert metal with very stable chemical properties.
3. Gold has good wear resistance.
If the connector has higher environmental resistance requirements and high reliability requirements, the general contact surface treatment of gold-plated.
Flexible application of gold coating
1. General gold plating bottom coating for nickel, can improve the coating life.
2. If the connector has cost requirements, the intermediate coating of the contact piece can be made of palladium nickel alloy, and the outer coating can be made of thin gold plating.
In conclusion, gold coating is the most commonly used surface treatment method for contact parts.
1: Silver has excellent conductivity.
2: The chemical properties of silver are unstable, and it is easy to produce silver sulfide by chemical changes with sulfur in the atmosphere. Silver sulfide will cause discoloration, electrical conductivity and welding performance of contact parts to drop significantly.
3: Compared with gold, silver has a cost advantage.
If the connector has high electrical conductivity requirements or large working current, the working environment is good, contact surface treatment can be used silver plating.
The electrical conductivity of tin is slightly worse than that of gold and silver.
To improve the solderability of the contact piece, the surface treatment method of partial tin plating on the end of the contact piece can be adopted.
The plastic shellof the electronic connector is made in the injection stage. The usual process involves pouring molten plastic into a metal film and then rapidly cooling it into shape.
Plastic shells are molded from common materials such as plastics and resins, and their chemical and electrical properties make them ideal connector shells.
Common plastic shell material:
1: low cost engineering grade plastics
2. Provide good strength, toughness and elasticity
Disadvantages: It will absorb water and cause dimensional instability
1. Good dimensional stability
2: high intensity
Disadvantages: The price is higher than nylon.
Liquid Crystal Polymer
1: strong resilience
2: can shape very thin wall thickness
3: able to withstand high temperature in surface tissue technology
Disadvantages:It's higher than other plastics.
The final stage of electronic connector manufacturing is final assembly. There are two ways to connect the electroplated pin with the injection box seat: single pin or combined pin. Single insertion means one pin at a time; Combined pair inserts connect and insert multiple pins with the box seat at the same time.
And regardless of the type of insertion, the manufacturer requires that all pins be checked for defects and correctly positioned during the assembly phase.
Assembly is the last stop of connector production. After stamping and Plating metal terminals and plastic shell formed by molding, finished products are produced after assembly workshop. Then delivered after packaging.
The above four manufacturing links, each link of the product size requirements are extremely strict, so only to carry out strict measurement to ensure that the product meets the qyality requirements.