Full color photoelectric sensors offer a new level of capability that makes sure the right steps happen in a production process, also known as “error proofing.” Not only can they precisely match colors and reflectivity values, they can identify and exclude or include near color matches on dissimilar as well as similar surfaces. Their reflectivity identification capability also allows them to identify invisible markers on products — perfect for error proofing packing lines.
How they work
Most color sensors contain a white light emitter and three separate receivers. The light is reflected off of the target and returns to the sensor. The receivers are tuned to look for a specific wavelength of light (one each for Red, Green and Blue) and record the components of the reflected light and its intensity. The sensor then compares these values to settings you made to determine the necessary action.
Programmable tolerance settings in the sensor also make it possible to tightly control the match of the target to the programmed value. This capability is important when sorting or matching objects of similar color. The more exact the required match, the more tight the color tolerance level is set. Models are available with up to 15 individual color outputs.
Unlike vision sensors that are designed for pattern detection, contour verification, or edge location, full color sensors are aimed only at a specific spot on the target that verifies that the right product or the desired attribute is present. This lets them operate at speeds as fast as 1 ms, which is much faster than the typical 20 ms update time required by vision sensors.
Full color sensors optimally suit a wide range of applications. For example, automotive carpet manufacturers use full color sensors to match carpets to vinyl heel pads — two dissimilar surfaces — where the color variation may be indistinguishable to the naked eye. This check ensures assembly quality and can save the OEM costly rejection of an entire lot of carpets by the car manufacturer due to a color production error.
Full Color sensors are one of the most versatile sensors available.
Packers use color sensors for product sorting and contents verification applications, while meeting the demand for high-speed production. Those who assemble products with multiple colored pieces check their process with color sensors to ensure quality. Starting at about $500, full color sensors are well worth the investment. Here two sensors work in concert to double check labels against cap color, thus verifying that the right product is in the bottle.
For further information, contact Tom Draper at [email protected] or go to >www.balluff.com/bfs
Filed Under: Electronics • electrical, Sensors (position + other)