The Manufacturing Process Of Electronic Insulated Terminal

There are many kinds of electronic insulated terminal, but the manufacturing process is basically the same.

The manufacturing of wire crimp terminal can be generally divided into four stages: stamping, electroplating, injection molding and assembly.



The manufacturing process of wire crimp terminal usually starts from stamping pins.

The wire crimp terminal pin is made of thin metal strip by large high-speed stamping machine.

One end of the large coil metal belt is fed into the front end of the stamping machine, and the other end passes through the hydraulic working table of the stamping machine and is wound into the tape feed roller.

The metal belt is pulled out and by the tape feed roller rolled up, then the finished products are stamped out.



The wire crimp terminal pins shall be sent to the electroplating section after stamping.  

Similar to the stamping stage, problems such as pin distortion, breakage or deformation will also occur when the stamped pins are fed into the electroplating equipment.  

For most machine vision system suppliers, many quality defects in electroplating process are still forbidden zones for detection systems. 

Custom crimp terminal manufacturers hope that the inspection system can detect various inconsistent defects such as fine scratches and pinholes on the electroplated surfaces of connector pins.

These defects can be easily identified on other products (such as aluminum can bottoms or other relatively flat surfaces).

Due to the irregular and angular surface design of most electronic connectors, it is difficult for the visual inspection system to obtain the images needed to identify these minor defects.  

This is a very difficult task for vision systems using black-and-white cameras, because the image gray levels of different metal coatings are virtually the same.

Although the camera of color vision system can successfully distinguish these different metal coatings, the problem of lighting difficulty still exists due to the irregular angle and the reflection effect of the coating surface.

Injection molding


The injection molding box base of the electronic insulated terminal is made in the injection molding stage.

It is the usual process is to inject the molten plastic into the metal mold, and then form the base through rapid cooling.

The so-called “omission” occurs when the molten plastic can not fully fill the mold, and it is a typical defect that needs to be detected in the injection molding stage.

Other defects include the filling or partially clogging of the sockets (these sockets must be kept clean and unobstructed so that they can be correctly plugged into the pins in the final assembly).

The machine vision system for quality inspection after injection molding is relatively simple and easy because the omission of box bases and the blocking of sockets can easily be identified using backlight.



The final stage of electronic insulated terminal manufacturing is the assembly of finished products.

There are two ways to connect the electroplated pin and the injection box base: single plug-in or combined plug-in.

The single plug-in is to insert one pin at a time; the combined plug-in is to connect multiple pins with the box base at the same time.

No matter which type of insertion is adopted, manufacturers require to inspect the omission and the correctness of positioning of all pins during the assembly stage; another kind of routine detection task is related to the spacing measurement of the connector matching surface.  

Although most assembly lines detect one to two pieces per second, the visual system usually needs to complete several different detection items for each connector passing the camera, so the detection speed becomes an important system performance index again.

After the assembly, the external dimensions of the crimp terminal on the order of magnitude is greater than the allowable dimensional tolerances of a single pin, which also poses another problem for visual detection systems.