Have you ever purchased a product from a reputable company only to have it fail or stop working a short time after you purchased it? Often, this is because the QA procedures employed by the company aren't set up to check all products—many companies perform only a random inspection during production.
As part of the Fortune 500 company Tyco, Guangdong Tyco Electronics Co., Ltd. (U.S.) primarily manufactures connectors and cable assemblies, with sales in 2007 exceeding $200M USD (over RMB Yuan 1.6 billion). As the largest global manufacturer of electronic and electric components, Tyco Guangdong Electronics' high production yield of 1000 of each set of equipment per day at a maximum of 1200 pieces per minute makes on-line product inspection nearly impossible for the operator to consistently control the quality of all products on the line. For on-line product inspection, a random inspection was the primary solution; however, it generated a lot of waste and damaged equipment. This is why Tyco Guangdong Electronics introduced a Cognex vision system with the help of their trusted partner, Shanghai Ximing Vision Technology Co., Ltd.
Comprehensive integrated vision system
Based on the characteristics of the stamping part industry, Ximing has developed a platform providing Tyco with the statistical data they need to inspect for defects. Since the inspected parts of the products are replaced very fast, and the repair is usually completed within two hours, Ximing chose the simple and well-developed Cognex In-Sight® 5000 Series vision system to guarantee consistent production. This inspection platform is equipped with the function of automatically saving the product picture, collecting flawed product data and displaying a size and trend chart of all products on the interface. The system also uses a Zeiss Telecentric Lens, which solved the large scene depth problem of stamping parts.
After the system was integrated, all sizes of products can be tested in order to judge whether they lack the pin—the most common defect. The repeatability of the system inspection is 2u, which is within the 10u quality standard required, compared with the 3-element test that has already exceeded the inspection demands of the customers.
Trust in machine vision
Cao Wuxiu, Vision Senior Engineer of Guangdong Tyco Electronics Stamping Department, indicates that, "Machine vision has already been in use for eight years and this system is primarily used to control the product quality. In conventional quality control, the product quality is primarily monitored via random inspection; therefore, it is difficult to detect some intermittent shortages of quality. The 100% on-line inspection can be realized via machine vision, thus greatly expanding the quality control range; and, as a result, complaints from the customers can be reduced or avoided. Costs can be saved when quality is controlled, and because the machine vision can realize 100% of the on-line inspection, product problems can be found as soon as possible, and the rejection can be reduced to a minimum. At the same time the condition of the production device can be indicated via the inspection data of machine vision, thereby guaranteeing product stability through replacing parts in advance."
Cui Luoping, Senior Vision Engineer of Guangdong Tyco Electronic Engineering Department, indicates: "I learned about Cognex in 2003 and I use it proficiently now. I've benefited much from its comprehensive function and simple operation, especially in the connector industry. Moreover, the number of rejected products has been decreasing continuously since they are more and more precisely produced. What is more, our workload has been greatly reduced by its function and applicability and the product quality has much improved. We trust Cognex."