Intralox, a leading global supplier of conveying systems, was looking to improve the speed and precision of its ARB Pallet Layer Former S7000 unit. Pneumatic cylinders did not provide enough flexibility, and early electric solutions were not suitable for washdown applications. A collaborative product development effort led to the design of a fully enclosed electric actuator that reduced maintenance and improved the palletizing unit’s performance and precision. This prototype was the basis for the ERD actuator from Tolomatic, Inc., designed as a cost-effective replacement for pneumatic cylinders, especially in washdown applications.
Intralox’s palletizing unit features the company’s Activated Roller Belt™ (ARB™) technology, which only moves containers linearly but has the ability to move them either left or right, turn them around, or sort them to a specific location in a pallet layer. The conveyor belt is able to do this thanks to actuators located in zones beneath the moving belt that activate longitudinal rollers in the ARB, making them rotate left or right. As a package passes over a diversion zone, for example, the actuators beneath the belt rotate pinions that cause the longitudinal rollers in the belt to rotate as they pass over, moving the container laterally by a predefined amount. Any given 10-foot section of the ARB may contain 8 to 16 actuators, depending on the complexity of the application. With this arrangement, packages can be pushed a few degrees right or left, make a complete 90-degree turn, or anything in between as they move along the belt.
In the past, Intralox used pneumatic cylinders to activate the pinions beneath the belt, but they could only provide fixed increments, meaning there was less flexibility in what the ARB could do. Going to an in-house-designed electric actuator solution allowed more precise movements of the actuators and provided more flexibility in diverting, sorting and turning of containers. However, the in-house actuator proved to be less than a total solution.
“We originally were making our own custom-designed ball screw with another vendor,” said David Marsh, senior electrical controls engineer with Intralox. “It was essentially just an open ball screw driven by a stepper motor. Because the ball screw was unprotected, it required more maintenance and was not well suited to washdown applications in food and beverage—one of our largest markets. Tolomatic came in and said they could build us a better solution, so they took what we had and made it better.”
In conjunction with Tolomatic’s area distributor, Penn Air and Hydraulics in York, PA., Tolomatic began designing a number of prototype actuators that would be simple, affordable, and work in food and beverage washdown applications.
“We were already providing Intralox with pneumatic cylinders,” said Jon Blum, sales engineer with Penn Air and Hydraulics, “but they were finding that a lot of their customers today do not want to use air cylinders. They want the controllability of a motor-driven electric actuator. So, with Tolomatic’s help, we sought to transition them to a better electrical solution than they had developed in-house.”
In the process of developing an actuator solution for Intralox, Tolomatic used information gathered from Intralox and other similar customers to design a completely new catalog product line called the ERD. Some of the specifications that Tolomatic built into the prototypes for Intralox have been retained in the standard catalog product line. These features include force capabilities up to 500 pounds, all-304 stainless steel body construction, configurable stroke lengths up to 24 inches, and ingress protection to IP67.
Intralox drives the ERD with a high-torque stepper motor through a coupling designed by Tolomatic to stand up to harsh use. The actuator only moves +/- 6 mm each time it activates a pinion beneath the moving belt, causing a longitudinal roller in the belt to rotate right or left. The duration of the actuator stroke is only 50 milliseconds, but with a conveyor belt moving 250 packages per minute, the actuator moves four times a second. “This represents only a 25 percent duty cycle,” said Marsh, “but it’s still a lot of movement, force, and action on a ball screw. In addition to durability, Tolomatic ERD gives us flexibility and programmability, and in most of our applications, it’s the best choice.”
Many of Intralox’s applications involve sortation work for food manufacturers and food and beverage warehouses. “What they want to do is put five boxes down one lane and five down another lane. What’s unique with this ARB technology is that once we shift it to the divert position, we can stay in that position, and everything behind the first one is going to go left or right,” said Marsh. “This is unlike a popup-style diverter where you have to return it to the zero position before you can divert another box. We can actually do a ‘slug’ of products, which can optimize a lot of throughput for our customers.”
Another concern Intralox had with its in-house ball screw design was that replacement parts were hard to source for customers overseas. Since Tolomatic’s markets are global like Intralox’s, there is an existing supply network to help customers with repair, service, or parts anywhere in the world. Marsh summed it up by saying: “The solution has gone from our small, custom-designed actuator to this globally supported ERD product.” For Intralox, it means that the company’s global product support is now running as smoothly as its state-of-the-art conveyor systems.
