Page 84 - MetalForming October 2011

Tooling Technology
press can still cycle, resulting in a bad part. Reworking the tooling or adding proximity sensors to detect part-in- place was not an option, so KLS opted for an entirely different approach.
“We decided to look at the part from outside the die using a vision camera,” says Shaw. “We use a pair of pattern- match detectors on the reference image captured by the camera and have the camera inspect for the correct orien- tation (Fig. 2). When both criteria are met, the press can cycle and a good part is produced. And when both pat- tern criteria are not met, the operator receives a signal indicating improper part orientation in the die.”
Case III: Zero Defects at High Volumes of Muffin Pans
At G&S Metal Products, Cleveland, OH, the largest U.S. producer of metal bakeware, high-volume stamping often means using dedicated presses for par- ticular jobs; long production runs with modular tooling for various similar
Fig. 2—Stamping heavy-gauge steel plate at KLS Controls, it’s critical that the operator loads the part into the press with the proper orientation, or the part becomes scrap. To detect proper orientation, the firm decided to look at the part from outside the die with a vision camera, using a pair of pattern-match detectors on the reference image cap- tured by the camera. This screen-grab from the camera controller shows a yellow box, which is the region of interest. Should the operator improperly position the part, only one or none of the green boxes will appear.
parts; and little time for scheduled maintenance, not to mention unplanned downtime. Inherited tool- ing often can provide little room for design changes or improvements. And,
if a die has been damaged, the die shoe may be in less-than-ideal condition, with sections altered. Therefore, con- sistently producing good parts from the inherited tool can be a challenge.
82 MetalForming/October 2011
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