Custom vinyl tile stacking machine: easy maintenance, quick repairs
Challenge
This flooring manufacturer invested in a second extrusion line for vinyl tiles.
He needed a stacking machine for three different areas within that line to stack and unstack those tiles. Each stacking machine had to be able to handle three different tile sizes.
This flooring manufacturer looked beyond the standard solutions on the market. He had three reasons for doing so:
- For his specific product, standard robotic solutions are oversized and therefore overpriced. These vinyl tiles may be more than two meters long, but they are also lightweight at the same time. Whereas with a standard robot, payload and reach are inseparable. A customized solution in this case is financially more interesting.
- An off-the-shelf stacking machine is a closed system. A black box. Also in terms of maintenance. Whereas this floor manufacturer wanted to entrust maintenance to its in-house team of technicians.
- Maximize uptime. After maintenance or repairs, it is often a challenge to get the alignment perfect again. That fine-tuning takes time. Time that is not available in this continuous production process.
Additional challenge for these custom stacking machines: vinyl tiles sometimes stick together. As a result, the gripper manipulates not one, but two or more at the same time. We had to solve that.
In addition, the customer put forward a cycle time of no more than 8 seconds.
Solution
The custom stacking machines we designed and built consist of two major parts:
- A custom gantry
- A custom gripper
Custom gantry
For movement alignment we chose rubber-coated wheels on both sides of the framework, instead of standard linear guidance systems. The Vulkollan elastomer eliminates slippage. The wheel systems on both sides, combined with an encoder, guarantee perfect alignment.
We applied this principle for both the X and Y axes of the custom stacking machine. This design makes maintenance easy. With an XY-standard system, you have to replace the entire linear guide in case of a defect. Time-consuming. And then you have to completely realign the system. Another waste of time. Our design overcomes this. The worst case scenario for their technicians is that they have to replace a worn wheel. That’s it. And this also avoids them having to fine-tune everything all over again.
For propulsion, a servo motor was the logical choice. This technology combines accuracy with acceleration force. A servo motor reacts quickly and immediately reaches full power. To meet the predetermined cycle time, the ability to accelerate and decelerate quickly was a must. After all, the gripper had to cover a considerable distance within 8 seconds.
Customized gripper for custom stacking machine
The gripper itself then. Whereas we chose steel for the framework of the stacking machine, aluminum was the logical choice for the gripper. Aluminum? That probably raises a few eyebrows. After all, steel is much stronger, isn’t it?
Yet aluminum was the best choice here. Precisely because vinyl sheets weigh very little. For these lightweights, an aluminum gripper more than suffices.
This material also allowed us to integrate a lighter servo motor. Together with the lower material cost, this reduced the price of the machine. Of course, for heavier products, steel is and remains the better choice.
We conclude with the peeling: our solution for seperating the panels. We placed the suction cups on each side of the gripper at a different height. We also included a suspension.
As a result, one row touches the tile first. This allows air to get between the two tiles. By the time the second row begins its manipulation, that air causes both the tiles to come loose.
Results
- A custom stacking machine tailored to the customer’s product and application. And at the same time financially more interesting than a standard solution.
- Simple maintenance. The IP of the machine goes entirely to the customer. So their in-house technicians can carry out maintenance themselves.
- Fast repairs. If a breakdown occurs, the technicians only need to replace a wheel at most. Realignment is not necessary. So maximum uptime is guaranteed.