Connector production process, a wide variety of electronic connectors, but the manufacturing process is basically the same, connector manufacturing can be generally divided into stamping, electroplating, injection molding, assembly of four stages.
The manufacturing process of electronic connectors generally begins with stamping pins. The electronic connectors (pins) are stamped from thin metal strips through a large high-speed punching machine. One end OF THE LARGE ROLLING METAL belt is sent to the front end of the punching machine, and the other end is wrapped into the rolling belt wheel through the hydraulic workbench of the punching machine, and the rolling belt wheel pulls out the metal belt and rolls the finished product.
The connector pins should be sent to the electroplating section after stamping. At this stage, the electronic contact surface of the connector will be coated with various metal coatings. Similar PROBLEMS TO THE STAMPING STAGE, SUCH AS DISTORTION, FRAGMENTATION OR DEFORMATION OF THE PINS, CAN ALSO OCCUR DURING THE STAMPING OF THE PINS into the plating equipment. With the techniques described in this article, such quality defects can be easily detected.
However, for most machine vision system suppliers, many quality defects in the electroplating process are still in the "forbidden area" of the detection system. Electronic CONNECTOR MANUFACTURERS WANT DETECTION SYSTEMS THAT CAN DETECT A VARIETY OF INCONSISTENCIES SUCH AS SMALL SCRATCHES AND pinHOLES IN THE ELECTROPLATED SURFACES OF CONNECTOR PINS. Although these defects are easily recognized in other products (such as aluminum can bottoms or other relatively flat surfaces); However, due to the irregular and angular surface design of most electronic connectors, it is difficult for visual inspection systems to obtain images sufficient to identify these subtle defects.
Since SOME types OF PINS NEED TO BE coated WITH multiple layers of METAL, MANUFACTURERS ALSO WANT testing systems that can distinguish between metal coatings to verify that they are IN place and in the correct proportion. This is a difficult task for a vision system that uses a black and white camera because the gray level of the image is virtually the same for different metal coatings. Although the camera of the color vision system can successfully distinguish between these different metal coatings, the problem of illumination is still difficult due to the irregular Angle and reflection effects of the coated surface.
The plastic case holder of the electronic connector is made in the injection molding stage. The usual process involves injecting molten plastic into metal membranes, which are then rapidly cooled to form. A typical defect that needs to be detected during injection molding is a "leak" that occurs when the molten plastic does not fully fill the membrane. Other DEFECTS INCLUDE THE FILLING OR PARTIAL BLOCKAGE OF THE CONNECTING jACKS (which MUST BE KEPT CLEAN SO THAT THEY FIT CORRECTLY WITH THE PINS DURING final ASSEMBLY). Because the use of backlight can easily identify the box seat leakage and plug plug, so the machine vision system for quality inspection after injection molding is relatively simple.
4, the assembly
The final stage in the manufacture of electronic connectors is final assembly. There are two ways to insert the electroplated needle and injection box seat: single insertion or combined insertion. Single insertion refers to each insertion of a pin; Combined pair insertion is to connect multiple pins with the box seat at the same time. Regardless of the insertion method, the manufacturer requires that all pins be checked for defects and correct positioning during the assembly phase; Another kind of routine detection task is related to the measurement of the distance between the mating surfaces of connectors.
As with the stamping phase, the assembly of the connectors also presents a speed challenge to the automatic inspection system. Although most assembly lines have a beat of one or two pieces per second, the vision system typically completes several different detection items for each connector passing through the camera. Therefore, detection speed becomes an important system performance index again.
When assembled, the outer dimensions of the connectors are orders of magnitude larger than the dimensional tolerances allowed for a single pin. This poses another problem for visual detection systems. For EXAMPLE, FOR SOME CONNECTOR BOX HOLDERS THAT ARE OVER A FOOT IN SIZE AND HAVE HUNDREDS OF PINS, THE ACCURACY OF EACH PIN POSITION MUST BE WITHIN A FEW THOUSANDTHS OF AN INCH. Obviously, THE DETECTION OF A foot-LONG connector cannot be ACCOMPLISHED in a single image, and the visual inspection system can only detect a limited number of pin qualities in a small field of view at a time. There are two ways to complete the detection of the entire connector: using multiple cameras (which adds to the system cost); Or when the connector passes in front of a lens, the camera is continuously triggered, and the vision system "stitches" together the continuous ingested single frame images to determine whether the overall connector quality is up to standard. The latter method is usually used by the PPT visual inspection system after the connector assembly is completed.
"Actual location" detection is another requirement of the detection system for connector assembly. This "actual position" is the distance between the tip of each pin and a specified design baseline. The visual inspection system must make this imaginary baseline on the inspection image to measure the "actual position" of each pin vertex and determine whether it meets the quality standard. However, the reference points used to delineate this reference line are often NOT VISIBLE on the actual connector, or sometimes APPEAR on another plane and cannot be SEEN AT the same time IN the same SHOT. In some cases, the plastic had to be removed from the connector box to locate this reference line.