Producing wheels ready for installation – with high process reliability and maximum flexibility
Darmstadt, October 2015 – From the 14-inch wheelset for compact vehicles to the 23-inch wheelset for premium and luxury cars: Schenck RoTec's new fully automated wheel/tire assembly line is a highly efficient and versatile solution for just-in-time production. Its flexible VENTUO inflation system sets technological standards. Another highlight of the assembly line is the robot which accurately attaches correction weights to the inside of the rim in the unbalance correction station.
Safety requirements have become more stringent, and the range of wheel/tire combinations has increased. This has prompted the engineers at Schenck RoTec to examine each individual process stage and to develop the new wheel/tire assembly line.
To begin with, two driven roller conveyors and an industrial robot position the incoming tires and rims, which are initially separated from each other, so they can be "married" fully automatically while protecting the material. During the marriage process, the lower tire bead is drawn onto the rim by a robot, and the upper tire bead, more conventionally, through a 360 degree rotation of the mounting head.
Following assembly, the pressureless wheels run on conveyor belts to the VENTUO multi-ring system for inflating. Its magazine stores up to six inflation rings, each covering two wheel sizes, which can be moved into position within just two seconds. This enables a variety of wheel sizes with diameters from 14 to 23 inches to be processed within approx. seven seconds. VENTUO is the only inflation system in the market offering this level of flexibility.
The VENTUO multi-ring system
Once the wheel/tire assemblies have been inflated to the right pressure, fully automatic tire seat optimization takes place. Irrespective of rim design and tire dimensioning, all wheel/tire combinations can be processed by changing pressure loads. A uniformity test is then carried out to check the wheel/tire assembly for minimal force variations and geometric deviations.
At the unbalance measuring station, the unbalance of the wheels is measured in two planes. The CAB 950st measuring and control device, which has been specially optimized for the production of wheel/tire assemblies, provides accurate data and even suggests where correction is required. CAB 950st also impresses with its simple SmartTouch operating concept.
Robot accurately attaches correction weights
In the case of unbalance, special correction weights are subsequently attached to the inside of the rims. Here Schenck RoTec sets standards with its fully automated unbalance correction station. With great precision and in line with the sequencing of the entire system, the correction weights are supplied to the robot as endless coils. With pinpoint accuracy, it attaches them to the position defined by the balancing system, thus providing maximum process reliability. Modern sensor technology ensures the required pressure to adjust the weight to the rim radius for optimum fit. Thanks to the robot, the cycle time of the correction station is reduced to just seven seconds from the predecessor model's 10 to 14 seconds.
The "fingerprint" analysis tool, which is integrated into the balancing machine as standard, quickly identifies any changes to the system. It is used for preventive monitoring of the entire system and enables targeted maintenance measures.
The new Schenck RoTec assembly line also impresses with its reduced energy consumption in many places. The VENTUO inflation system, for example, uses 30 percent less energy-intensive compressed air compared to its predecessor model.