Controls Deliver Smooth Movement in Robotic Press Cell

In 1959, two brothers with an entrepreneurial bent, John Bundy Sr. and Russell T. Bundy, founded a commercial bakeware business that, over time with the Bundy family at the helm, grew to become the largest such manufacturer in the world. In 2009, Premier Pan expanded with the creation of USA Pan, a retail brand of commercial-quality bakeware. Today, four generations of the Bundy family operate the businesses out of Pittsburgh, PA, shipping product worldwide out of several production centers located across the United States. 

Known for sturdy products with lifetime guarantees, the Premier Pan business relies on sound, efficient and reliable processes, materials and equipment to maintain needed quality. Experience gained on the bakeware front has enabled expansion into other drawn products for other end uses. This includes production of drop-box dryer vents—the focus of this article—at a 115,000-sq.-ft. operation in Crescent, PA. Here, 210 employees operate in two shifts. 

Hundreds of machines dot the production floor of USA Pan in Crescent, including gap-frame and straightside mechanical presses to 600-ton capacities, as well as press brakes and CNC machines for tool and die build and repair. Other operations include shearing to create blanks as well as welding and assembly.  

Switch from Labor-Intensive Process

The high-performance vents designed by USA Pan are used to protect exhaust ducts in wall connections, prevent fire spread and help dryers perform at peak efficiency. USA Pan sought, in 2019, to switch from a labor-intensive process for production of two styles of drop-box vents to an automated stamping cell, according to robotics engineer Guy Cole, a 10-yr. veteran at the company and tapped to lead the project. 

Following more than six months of planning, a cell anchored by three mechanical presses and three robots entered full production in October 2019. Tasked with overseeing operation of the cell: PPC 1000R resolver-based, dual-logic controllers from Cieco Controls, headquartered nearby in Clinton, PA, and a provider of control units for many other USA Pan presses.

In operation, a new Worldpress TNCF3-series NC servo straightener and feeder with uncoiler feeds 0.028-in.-thick aluminized steel sheet into a straightside press that provides the principal draw forming of the vents, to a depth of 4.25 or 3.5 in. depending on what style is running. The coil feed then pushes the vents on a motorized conveyor to one of three Fanuc R-2000 iB/165F robots in the cell, which picks up parts one at a time as they are presented and places them on a locating die for the next operation. Here, a second gap-frame press with three dies performs trimming, wiping and nail-hole stamping. Another Fanuc robot tends this operation as the parts move through, providing output to the Cieco press control to determine press cycling. The robot then transfers all four vents with one vent exiting that operation to a locating die for a third straightside horning press that creates a vent hole and gas-line knockout. Tending the third press, another identical Fanuc robot picks the vent from the locating die and transfers it vertically into the press for the knockouts. This robot also outputs signals to a Cieco control for press cycling. Upon part completion in the third press, the robot then places the vent on a motorized conveyor for transport to a palletizing station. This is the only area of the cell with a human presence, for inspection and for manual stacking on a pallet.

With three robots operating in proximity and sharing stations, discrete I/O communication between the robots prevents them from crashing into each other, according to Cole. Two styles of vents run on the line, and a few factors enable quick and simple job changeover.