Simplicity is not sacrificed in demanding a vision system for high quality production
Strengthened by their initial experience in the automotive sector, 2BG needed to explore new opportunities to develop their business activities. Taking into account their automotive experience and considering market trends for the development of new sources of clean energy, 2BG decided to start producing machines for the manufacture of solar cells.
The first tabbing machines for the production of solar cell panels used a mechanical alignment and centralizing system was difficult to calibrate. In addition, the direct mechanical contact of this process risked damaging the cells themselves. Therefore, the solar panels could potentially have tiny surface defects at the end of the production and were not well aligned.
The research and development team at 2BG decided to investigate innovative technological systems that could improve their already high standards of quality control and eliminate all potential defects during production.
Cognex—the natural choice for the machine builder
With exactly this in mind, and after having attended a Cognex vision seminar, the 2BG R&D team came to Cognex to discuss their application. After an initial evaluation phase, 2BG decided to test In-Sight vision systems. The application was rapidly planned and installed by the 2BG team on a first prototype and the final result was excellent.
High performance machine
The TS600 tabbing stringing machine solders the solar cells into strings for the production of the solar cell panels. Highly automated, the machine is capable of working according to different product cycles, which can be internally memorized, producing up to 600 cells an hour. Thanks to high speed pick-and-place and the infrared soldering system, this kind of high level production was possible to achieve.
In-Sight for alignment
An automatic centering mechanism station was planned using In-Sight® vision systems from Cognex; this innovation reduced mechanical contact to a minimum thus preserving the integrity and the quality of the cells. The precision of the centering was greatly increased thanks to PatMax®, a patented vision tool exclusive to Cognex that locates objects under difficult conditions: changes in dimension, orientation or lighting; in cases of deformation, occlusion, or reflection; and with confusing backgrounds or in other environmental conditions. The surface of the cell is similar to a mirror with a reflective surface, making it difficult to inspect. Given that the search principle of PatMax is insensitive to a reflective surface, the use of PatMax is a real trump card ensuring high precision and reliable long term performance.
In-Sight again for inspection
Following the production process, the cells are automatically picked up from two loading baskets and the final string is deposited on a lighting table for quality inspection. Thanks to the comprehensiveness of the vision tool library from Cognex, it is possible to examine superficial defects such as small marks or dents in the form or on the edges of the cell, as well as verify the continuity and the correct assembly of the string. Such a complete range of inspection checks was possible thanks to the calculating power and speed of the In-Sight systems. There is also an optional element on each vision station, and a multilingual, interactive touch screen that can be personalized according to client needs.
And finally In-Sight for simplicity
Today, the In-Sight family of vision systems is indispensable for 2BG because it guarantees such high quality production. For 2BG, it’s impossible to imagine their machines without Cognex systems; “Cognex total reliability, the most innovative technology and top order service allows us to satisfy our own high quality standards every time, as well as being able to efficiently plan our business. Another advantage is the fact that In-Sight operates in a simple and efficient manner.”