Bauke Van den Akker is one of the directors of the engineering firm based in the Netherlands and his colleague Lourens is one of his engineers. Lourens explains that the official name is a "basket loader/unloader" and that this name will also be used for the documentation when this interesting piece of Dutch technology starts its long journey to its destination, the Ivory Coast. This could just as easily have been Indonesia or New Zealand, because Apollo Engineering's clientele operates all across the world.
As the name suggests, this machine is intended for loading and unloading baskets. The baskets are filled with cans with contents that need to be sterilized for extended hygienic storage. This is done under pressure and with steam in an autoclave. When this process is finished, the baskets complete with cans are removed from the autoclave and the cans are unloaded.
Previously, the handling was done manually by the end customer. Each can and its contents weigh roughly one kilogram, and a basket may contain up to 400 cans, stacked in layers with intermediate sheets, depending on the size. The customer believed this arduous process could be automated. Since they had already had positive experiences working with Apollo Engineering, they entrusted them with the challenge. The result was the automated basket loader/unloader.
In the modular machine, the cans are automatically supplied via a conveyor belt. The cans run against a stop and once enough cans are collected for a complete layer, new incoming cans are stopped. The collected layer is then transported until the cans are aligned under an ingeniously concealed magnetic plate. Assisted by Festo pneumatic cylinders for the vertical movement, the magnetic plate picks up the complete layer and places it on an intermediate sheet in the ‘ready’ basket. The can layer is again covered with an intermediate sheet, which is then picked up and deposited using a vacuum. This process is repeated until the basket is full.
The system is equipped with an OVEM vacuum generator for the vacuum handling of the intermediate sheets.The generator actively monitors the vacuum level with a built-in IO-Link® vacuum sensor. The air-saving function switches off the compressed air as soon as the set vacuum level is reached. This keeps compressed air consumption to a minimum, potentially saving up to 80% compared to a standard vacuum generator.
Once the basket is full of cans, it is moved using a chain conveyor. This frees up space for the next basket, which is also supplied. However, this does not yet complete the process of transporting the filled baskets to the autoclave and back again. During the design phase of the project, Apollo Engineering carefully considered this transfer, as dragging a filled basket is quite a heavy job. A solution was also developed for that: an electrically driven cross-brace. The cross-brace is capable of transporting a train of up to five linked baskets from the basket loader/unloader to the autoclave. After the sterilization process, the cross-brace brings the baskets back to the installation.
In addition to placing cans in the baskets, the second function of the machine is to take them out again. This is done on the opposite side of the system, where the steps are performed in reverse order. Although the design differs in detail, these are actually two functionally identical modules - with space in between serving as a buffer for empty baskets.
Apollo Engineering is more focused on pursuing modular designs although Bauke Van den Akker admits that most designs need some degree of customization and adaption so they can be used for another task. But he emphasized that it does make it easier to build on. The application of I/O signal processing is directly related to the pursuit of modularity. Lourens is a staunchadvocate of this concept, whichis also supported internally: "Just look at the conveyor system that needs to be built into this job and how much nicer it is to be able to simply plug in and connect all the components including remote I/O. You can have all that pre-prepared and then all you have to do is connect it and you're done."
That saves a lot of cabling, explains Bauke Van den Akker, which is confirmed by Lourens: "We are always thinking about how we can keep our builds as simple as possible. Sensors have to be cabled, there's no getting around that, but this is where the Festo CPX AP-I comes in."
Apollo Engineering has always used many CPX valve terminals from Festo. Its modular architecture allows it to integrate the bus node, remote I/O and valves into one modular component. This means that these valve terminals can be used centrally and decentrally and that all your devices - inputs, outputs and pneumatic actuators - can be connected directly to them. But was that the best technology for the basket loader/unloader?
Festo put the Apollo engineers on the right track for this application with the new decentralized I/O platform CPX AP-I, which flexibly and scalably connects I/O modules and decentralized valve terminals from Festo to all common control architectures. CPX-AP-I technology enables a modular and decentralized design, according to the size and layout of the machine design. Lourens attests to this, “with CPX AP-I, I can, for example, take two units and connect four sensors to one and two to the other. You hang them in the machine, couple them with the ready-made cables and you're done”. The VTUG valve terminals in the basket loader/unloader also have the same internal AP bus as the CPX-AP-I platform, so that they can be integrated into the system transparently and without any issues.
Bauke Van Akker also sees how the decentralized CPX AP-I platform supports Apollo Engineering's way of working. “In practice, it is really just a matter of linking and connecting the power supply. The various machine tasks can be prepared entirely during the setup at Apollo Engineering with the required I/O terminals and valve terminals. Cabling in the field is reduced to a minimum.“