Aunt Gussie's and Servo tech drives clamshell labeling

02 Feb 2011

After trying and rejecting two pressure-sensitive labelers for automated labeling of cookie-filled plastic clamshells, Aunt Gussie’s found the machine it needed.

At specialty cookie company Aunt Gussie’s Cookies and Crackers in Garfield, NJ, cookies are packaged in clear plastic clamshells. Labeling had always been done by hand, but as the volume of packages kept increasing, management began searching for a machine application solution. The search led ultimately to a Shell Shock pressure-sensitive labeler from Nita. But there were a few bumps along the road—two big ones, to be precise.

“This is the third machine I tried,” says company president David Caine. “We pack the cookies in pretty tight, and sometimes they do bulge a little, so it can be a tough container to handle. I installed two labeling machines prior to this one and had to send them both back. As I said, it is a difficult container to handle. But the Nita machine is really up to it.”

In this particular application, where cookies are hand-loaded, speed wasn’t a big concern. Far more crucial is the synchronization between the labeling head itself and the conveyor belt that delivers clamshells to the labeling head. If these two are not synchronized, problems are bound to surface. On the Shell Shock machine, servo technology ensures spot-on synchronization of conveyor and labeling head. Here’s how it works.

An AC motor from Nord Gear drives the conveyor that presents the clamshells to the labeling head. On the shaft of this motor is an encoder from Encoder Products Co. that counts revolutions of the shaft and communicates this data to a servo drive in the controls cabinet. This drive, the Unidrive SP from Emerson Control Techniques, has an SM-EZMotion module whose microprocessor controls the Shell Shock machine’s motion and I/O. Based on input from the encoder, the drive then regulates the Emerson servo motor that applies the pressure-sensitive labels. With the conveyor motor and the servo motor linked in this fashion, the clamshells are always traveling at just the right speed relative to the labeling head.

One other controls component on the Shell Shock labeling machine is the HMI screen, which comes from Beijer. “We do four different-sized containers,” says Caine. “All we do to go from one size to another is go to the touch screen and drop down on a menu to the size we want to run. The operator is then told on the screen which guide rail settings are called for. It makes changeover very easy.

“The other great thing about this machine’s accuracy and reliability is that it means we waste fewer labels and clamshells. That was the problem with the other labelers I tried. By the time we got the conveyor synchronized with the label application head, we might waste 20 or 30 packages and labels. Not anymore.”

Mounted on the labeling machine’s frame is an Evolution digital thermal ink-jet printer from Digital Design that prints a best-by date on every label. “The printer is inexpensive, reliable, and simple to operate,” says Caine. “It’s clean, too, because it takes cartridges like the ones you pop in and out of an office or home printer.”

Now that he has his clamshell labeling down pat, the next step for Caine is a more automated way of getting cookies out of the pans on which they are baked. For now, he’s happy to have his labeling woes in the rear view mirror.

Source: Aunt Gussie’s