At production speeds of 1,000 parts per minute, even a few minutes of downtime per day can quickly lead to thousands of dollars in lost production. This innovative feeding system keeps an ammunition assembly system on target.
An ammunition manufacturer for the military assembles full metal jacket rounds at a rate of 1,000 per minute. However, the machine that crimps the jacket to the bullet jammed frequently-as often as four times a day. Each jam shut down the machine for up to 30 minutes. With each round priced at $0.25, the problem was costing the manufacturer as much as $30,000 daily in lost production. Moreover, if the jam damaged the tooling, another $2,000 came off the bottom line for a replacement.
The jackets themselves were the source of the problem. Out-of-tolerance parts, damaged parts and even debris were all too common among the incoming jackets. The manufacturer needed a way to weed out bad parts before they got to the crimping press. Bowl maker Feeding Concepts Inc. solved the problem.
From a bulk supply, the jackets are fed across a set of adjustable rods that splay outward and down from the feed point. Parts slide across the rods and fall into bins at predetermined locations. Parts that are too thin drop through early. Those that are too wide drop late. Those that are just right fall into a vibratory bowl.
In the bowl, the jackets are singulated, oriented, flipped, and cleared of debris with compressed air. At the end of the bowl, the jackets pass through one last mechanical gauge. If the jacket is out of round by just 0.03 inch, it will stop at the gauge, where it is cleared automatically in less than a second.
As the jackets exit the bowl, they get one last check by a high-speed vision system. Three cameras inspect the profile, top and interior of each jacket. Thanks to the feeding and inspection system, jams have been eliminated.
For more information on parts feeders, call Feeding Concepts at 317-773-2040 or visitwww.feedingconcepts.com.
Editor’s note: “We Fed It” is a regular series profiling parts feeders for automated assembly. Whether it’s a vibratory bowl, a tray feeder or a flexible robotic system, if you’ve solved a parts-feeding challenge, we’d like to hear about it. Send an e-mail to John Sprovieri, editor of ASSEMBLY, at firstname.lastname@example.org, or call 630-694-4012.