Quality Innovations: High-Speed Inspection
Quality inspection is important to manufacturers, and if it can be done faster, so much the better.
The Cyprovision Mach 7, as the name implies, is not slow.
This automated vision inspection system from Dunkley International Inc. (Kalamazoo, MI) can inspect bolts, washers and screws at throughput rates up to 3,000 parts per minute (ppm).
The machine, introduced last year, sorts out mixed foreign material and damaged parts. An operator is required only to participate in the material handling of the fully weight-counted boxes after machine inspection.
Dunkley had been producing similar machines to sort industrial washers, but found a need for faster and more flexible equipment that also could inspect bolts and screws, says General Manager Ernie Kenneway. Many fastener manufacturers’ existing equipment limited how many parts they could inspect. In addition, products were being mixed together on the production floor, during heat treating or plating, or in the washing process. Some products were malformed or incomplete.
Dunkley’s goal was to create a vision system that would check the presence of thread, length, diameters, proper tip shape, straightness and remove foreign material at speeds of 2,000 to 5,000 ppm, depending on the size of the part.
Previously, with the combination of parts, some foreign parts would get mixed in and jam the customers’ highly automated systems. The parts may have looked similar, but would have different lengths or diameters.
Customer DemandBecause the machine can do 100% inspection and inspect for many different types of parts at a high speed, Kenneway says customers can buy a single machine that can do the work of 10 machines.
While this $100,000 product does not come cheap, Kenneway says the product justifies the cost with faster inspection speeds and higher resolution than what most customers have been using.
“Some of the guys are getting up to 6,000 pieces a minute,” he says. For example, a vibratory bowl feeder-based machine may be able to sort 150 to 300 pieces a minute. Products go down a chute single file and the machine is only able to inspect a sampling of the fastener manufacturer’s total product output. The Mach 7 is able to inspect high volumes at high speeds.
A screw company in Canada was the first to purchase the Mach 7. Because of the company’s work volume, it made sense to purchase this product, Kenneway says.
Dunkley also is building more machines to meet demand from customers that manufacture bolts, fasteners, screws and washers. And, as the automotive industry demands cost reductions from vendors, high quality and low prices are critical.
To keep average costs down, vendors may use products produced offshore. The cost savings may lead to quality problems, so while they are able to reduce the price to the OEM, it may also lead to quality issues, Kenneway says.
To solve this problem, one customer bought a machine to check incoming material from China before the material was shipped to their customer, Kenneway says.
After a customer acquires the Mach 7, the equipment does not require a lot of attention. The computer makes sure everything is running correctly so the operators do not have to interfere. To train the machine, operators simply run some of the good parts and let the computer capture the image. After setting the parameters, operators can save those settings for future use. By doing so, the next time they can plug in the part number and the machine is ready to go.
After the parts are inspected, an optional feature packs up the parts and seals the container immediately to prevent contamination.
Building these types of sorters is not new at Dunkley, where they have been doing this sort of work for the past 10 years. However, they had always been doing 2-D, and had not gotten into 3-D. The Mach 7 will inspect 3-D parts such as a bolt but the actual vision system is based on 2-D image information. If required, however, a 3-D vision system could be used if the application required it.
“It’s just been a lot of learning as you go along,” Kenneway says. “You learn something and incorporate it into the next iteration of the machines we build.”
Technology ContactFor more information about the Mach 7, contact:
- Dunkley International
1910 Lake St.
Kalamazoo, MI 49001