A key procedure in the assembly of automobile transmissions at the Volkswagen plant in Cordoba, Argentina, involves piecing together the top and bottom pieces of the transmission. A robot applies a sealant that helps join the two pieces. Smeared or irregular sealant lines, or sealant falling into the bottom block can result in a defective product.

In the summer, high temperatures can cause the sealant to soften, resulting in gaps in the sealant or sealant material dripping into the transmission block. Even when using a machine to keep it cool, the robot does not always function correctly. An effective seal is crucial to avoid transmission fluid leaks.

Three years ago, plant officials installed a machine vision system from DVT Corp. (Duluth, GA) to inspect these sealant lines. The system employs two Legend 530 cameras, a SmartLink to help control the cameras, brick lights and a back light.

The plant produces as many as 1,440 manual transmissions a day for Volkswagen, Audi and Seat automobiles. Because of the various combinations that result from different transmissions and car models, 35 different products can run on the line, with an average of two to three changes per day.

According to system integrator Fernando Fantini of NF NeoTec Industrial Solutions (Cordoba, Argentina), the machine vision system checks the transmissions for the presence of a continuous sealant line, the correct width of sealant and the presence of sealant inside the transmission block. The system has also been configured to identify the presence and position of a piece of tubing on a more recently introduced Volkswagen transmission.

When a defective part is identified, the system triggers an alarm that alerts the operator at the assembly station where the parts are manually joined. Instead of assembling the two parts, the operator takes the bad part off the line and sends it back to be resealed.

Volkswagen process engineer Mariano Periotto says an earlier machine vision system installed in another part of the factory requires six cameras to do what the newer DVT system is able to accomplish with its two. The result of using few cameras has been lower costs, both in terms of installation and operation. Since its installation the machine vision inspection system has proved 100-percent effective.

For more information on machine vision systems, call 800-762-6077, visit www.dvtsensors.com.