Tag: vision inspection

Super Air Wipe Helps Shield a Lens

Published on by johnball2014Leave a comment
Super Air Wipe Kit

A tier 2 automotive company makes small metal boxes with a process which includes laser welding and a vision inspection system. The machine was programmed to weld different components onto the metal enclosure. During the welding operation, an optical sensor would check the quality of the welds. The vision system used a lens to protect the sensor from welding slag and debris. After a few operations, they started seeing false positives in the welding areas, and the metal enclosure would be flagged for rejection. In investigating the issue, they found that the lens was getting dirty from the welding operation. Because of the sensitivity of the sensor, it would detect the debris and marks on the lens and signal for poor weld. The lens was doing its part in protecting the sensor from damage; but, they needed a way to shield the lens from dirt and slag during the welding operation and visual inspection.

With this process, the machine would weld metal fasteners onto an enclosure by laser. The optical sensor would move along the welded areas to check the quality. In a lead/lag operation, the vision system would check the welds after a few seconds of cooling. So, both operations were occurring at the same time but at different intervals. When they started to see the rejection rate increase, they would have to stop the operation, clean the lens, and verify the integrity of the welds. In some cases, they would have to replace the 1 ¼” diameter lens especially if a piece of welding slag marred the surface. With incorrect rejections and lens cleaning, downtime was hurting their production rates and cost.

This customer wanted to use compressed air because it is a powerful and invisible way to create a shield. Since EXAIR is a leader in efficient and effective ways to use compressed air, they contacted us for help. Initially, I suggested a Super Air Knife to deflect any slag and debris from the lens surface. I showed a prior solution to a very similar issue; “Air Shielding a Laser Lens” (Reference below). But, because of the proximity to the part and the limitation in space, the Super Air Knife  configuration in the solution below would make it impossible to use. They were looking for a product that could be mounted either flush or behind the surface of the lens and still protect it.

Air Shielding a Laser Lens

To accommodate for this request, we had to direct the compressed air stream at an angle. EXAIR manufacturers a product that can do just that, the Super Air Wipe. The design of the Super Air Wipe blows compressed air at a 30-degree angle toward the center in a 360-degree air pattern, just like a cone. It can be placed around the lens and still be able to create a “wall” of air to block any slag or debris from hitting the lens.

I recommended the model 2452SS, 2” Super Air Wipe Kit. This Super Air Wipe has the body, braided hose, hardware, and shims that is made from stainless steel. It can handle the high heat loads from the welding process as well as to allow for easy cleanup after a day of operating. The kit includes a filter, to keep the compressed air clean; a regulator, to finely tune the force requirement; and a shim set. The shim set includes two additional sets of shims that can be added to increase the force of protection if needed. With the kit, the customer can “dial” in the correct amount of force needed to keep the lens clean without using excessive amount of compressed air.

As an added benefit of saving compressed air, the Super Air Wipe uses the Coanda effect to maximize the entrainment of ambient air into the compressed air stream. This makes the unit very efficient and very powerful. The Super Air Wipe was mounted just behind the lens like the customer required (Reference mock picture below), and the sensor could examine the welds without any interference with the metal enclosure.

Laser Lens mock drawing

Visual inspections systems are highly accurate pieces of equipment, and a dirty lens will affect the performance. EXAIR has many ways to keep the lens clean with a non-contact invisible barrier to protect sensors, cameras, and lasers. If you have a similar application, you can contact an Application Engineer to determine the best way to keep the lens clean and your equipment functional. After mounting the Super Air Wipe, the customer above eliminated any false rejections, and dramatically decreased any downtime for cleaning or replacing the lens in his welding machine.

John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb

Ion Air Gun Used by the Quality Control Department

Published on by johnball2014Leave a comment

A Quality Control department had static issues when analyzing color swatches. Their production process was screen printing on polycarbonate sheets.  They had our Super Ion Air Knives and Ion Bars in their production process to remove static and debris.  During the die cutting operation, a color swatch was removed for QC to inspect.  They would use an instrument to verify the color and clarity.  During the inspection, they would periodically have a rejection.  In inspecting the swatches, they noticed a lot of debris that was collected on the surface.  This would affect the reading of the instrument.  They tried to wipe off the debris, but because of the static build-up on the surface, it was hard to remove all of it.  Being that they were familiar with EXAIR products, they contacted us and I suggested our Ion Air Gun.  The ions would remove the static while the air flow would remove the dust.  Once in use, the reliability of the inspection instrument was much improved.

Ion Air Gun
Ion Air Gun

One of our more versatile Static Eliminator products is the Ion Air Gun. You can turn the unit on and start blowing ionized air to remove static and contaminants from lenses, sheets, plastic wrap, plastic products and other materials holding a static charge.  It comes with a 3 meter cable to give you a long reach and a High Velocity Air Jet that produces a large amplification ratio to reduce the amount of compressed air use.  The ergonomic, light-weight, and rugged design makes it an effective air gun to remove both static and debris.

In this instance, the Ion Air Gun was a nice accessory for the QC department to clean surfaces before inspection. It made their job more effective and less time consuming.  If static is a big issue, you can always contact an Application Engineer for help.

John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb

2” Flat Super Air Nozzle Keeps Lens Clean

Published on by Neal RakerLeave a comment

camera lens1Camera lens with 1122

Many times we will be contacted by clients who provide vision inspection systems for a variety of industries. These companies are involved in applications to inspect everything from part conformance to product counting to processes to filling applications.

In the first photo above a customer had their vision inspection system set to inspect the filling of a powder material into its container. The problem is that the fine, dusty nature of the product would cause a small cloud to form near the filling point which would end up settling onto the lens area. Over time, so much build up would occur that the vision inspection system was rendered useless.

The customer had a small air jet set up as shown in the photo on the left, above. The problem with their air jet was that it did not provide full coverage across the width of the lens and allowed dust to still settle there. You can see it in the photo. After the customer contacted us and described the situation and the size of their lens, we recommended model 1122 2” Flat Super Air Nozzle with the thinnest shim available which is .005” thick.  The 2″ Flat Super Air Nozzle was able to provide an airflow that covered the full diameter of the lens and blast any debris away. In the end, they removed the homemade small air jet assembly and simply blew air across the lens with EXAIR’s nozzle. See photo on the right above.

Vision inspection cameras, lasers, and sensors are found in a variety of dusty and messy environments. Inspection systems on filling lines, sawing applications, weighing machines and grinding applications are just some of the notoriously problematic processes. If you are involved in a process that has trouble keeping the vision inspection lenses clean, the 2” Flat Super Air Nozzle is a great way to mount an engineered solution that won’t run you out of house and home on your compressed air usage. And best of all, it actually does a good job. If your application is slightly bigger, smaller, dirtier etc., EXAIR’s unmatched selection of nozzle and blowoff products can likely provide a solution.

Neal Raker, Application Engineer
nealraker@exair.com