One Two Beer, GmbH has developed an automated beer tapping system to reduce long lines and waiting times at festival beer stands. At its core is a mobile tap head built using igus’ durable, hygienic, and dry-running threaded dryspin® spindle. This allows the tap to quickly drive to the bottom of cups and fill them in just five seconds without foaming.
During the busy festival season, concertgoers often face annoyance from long beer lines that can cause them to miss parts of the show. To improve customer experience, One Two Beer’s automated system allows festival staff to place cups side by side, then, with one press of a button, the mobile tap heads descend to fill the cups from below. This bottom-up approach prevents foaming, so pouring happens rapidly. Concert attendees benefit from precious time savings and no more missed songs, while vendors benefit from labor savings. The automated system provides faster service to reduce frustration during peak times.
Dry-running operation was required
As simple and elegant as the beer robot may seem, its construction was a design engineering challenge.
“In order to enable tapping within seconds, a fast and low-friction linear guide was essential,” says Tamás Kozma, Chief Information Officer at One Two Beer GmbH. “Since our machine works in the food sector, a 100 percent lubrication-free application with FDA compliance was also crucial for us.”
The system was supposed to work accurately to the tenth of a millimeter, be as compact as possible for fast transport, and be insensitive to the harsh festival environment – including dust, high temperatures, and condensation.
After a long search, the company’s engineers finally found a system that meets these requirements at igus: a complete linear guide unit consisting of a compact lead screw and lead nut from the dryspin series and a matching stepper motor.
High-performance plastic and stainless steel enable hygienic and trouble-free dry running
Here is how the linear guide works. The tap is mounted on a flange lead screw nut from the dryspin JFRM series. The tap moves up or down when the NEMA 23 lead screw stepper motor rotates the lead screw. The system is relatively simple. However, some unique features exist: the lead screw nut is made of FDA-compliant high-performance plastic, a self-lubricating material that allows for low-friction dry operation.
The advantage is obvious. Unlike lubricated versions made of metal, the polymer nut will not become a dirt magnet due to lubricating grease. It is easy to clean with water or high pressure. The linear guide is hygienic, and its mechanical system works flawlessly. The pairing of plastic and stainless steel also prevents corrosion. As there is no need for relubrication, maintenance is also unnecessary.
Lead screw achieves an efficiency of 82%
Resistance to corrosion and dirt are not all that result in a long linear guide service life. igus has also enlarged the nut’s thread edges by a factor of 1.3 for dryspin technology. The lead screw’s thread pitch is also broader. Enlarged thread flanks mean more high-performance plastic for power transmission and, thus, more tribologically optimized material for friction and wear.
“This asymmetry has enabled us to extend service life to about 30% longer than that of symmetrical trapezoidal threads”, says Thorben Hendricks, Head of dryspin Lead Screw Drive Business Unit at igus. “We have also flattened the flank angles of the lead screw nut and lead screw. This gives us an efficiency of 82%, which is above average.”
Find out more about the igus products in this application at www.igus.com/e-motors/lead-screw-assemblies-with-motors.
Filed Under: LINEAR MOTION