Three SCARA Robots for Truly Efficient Testing

Tecnologika is a small but competitive company from Brugnera, in the province of Pordenone, specializing in the design and manufacture of assembly and testing machines, especially for the automotive and household appliances industries. Thanks also to the solutions available in the SCARA range of robots made available by Epson, and distributed in Italy by Sinta, the Friuli-based company has built a compact and high-performing machine for testing disk packs for electric motors, capable of lowrering cycle time to only 6 seconds.

by Fabrizio Dalle Nogare

Brugnera is indeed a border town, located between Veneto and Friuli Venezia Giulia. It belongs to a region, the latter, which in turn marks the eastern border of Italian territory. A green, hospitable and, above all, industrious land, with a fabric of small, highly specialised businesses also able, thanks to the typical Italian creativity, to compete on a global level. How is all this possible? Drawing on the best technology available on the market and combining it, as in the story we are about to tell, to create special assembly and testing machines.
Stefano Rossi, who welcomed us into his company and showed us a machine for testing disk packs for electric motors that was nearly ready for delivery, is the CEO of Tecnologika, “a small industrial automation company”, as he calls it, which employs no more than 15 people and has been operating under this name for less than 10 years. Mr Rossi’s experience in the sector is, however, longer. And it begins with a company specializing in the manufacture of electrical boards. “We used to integrate the electrical part, working in close contact with machine manufacturers”, he tells us. “Soon, however, what we were doing was not enough anymore, so we decided to take a step further and become manufacturers in turn. Over the years, we have built special assembly and testing machines for manifold sectors, even if today our activity is mainly aimed at the automotive and household appliances industries: two challenging sectors indeed in terms of customers’ requirements”.

Cross competences
Mechanical and electrical design, mechanical and electrical construction, software development and assembly of the machine itself. These are all activities that Tecnologika is able to carry out thanks to the presence of professionals with several skills. “About 80-90% of our machines are made in-house: some mechanical components are an exception, so we use selected suppliers”, explains the CEO. “We also work independently with regard to the software system for production traceability and local data collection and storage. We have trained staff within the company who can program the PLC as well as, for example, manage the robots. This is a feature that our customers greatly appreciate because it allows us to be quick in developing solutions, and today speed is an increasingly important variable”.
Speaking of customers, we ask Stefano Rossi if, in his experience, their demands on digitisation and data management are changing in the age of Industry 4.0. “Of course, we supply ‘Industry 4.0-ready’ machines, then there is a part of integration with the customer’s management system or connection to a higher level than the local one that we do not compete. In the field of assembly, traceability has become a standard. Government incentives have certainly raised interest in the next step, digitization itself, but we see that not everyone is ready yet”.

The SCARAs as a cost-effective solution for handling requirements
With regard to the evolution and changes that affect the design and manufacture of machines, it is quite clear, once set foot in the workshop, that robots play a key role in the idea of automation carried out by Tecnologika. “In fact – continues Stefano Rossi – for several years we have been working with robots and, especially in the last period, we have been using almost exclusively Epson robots for lightweight handling. Compared to a few years ago, when we opted mainly for six-axis robots, which gave us the possibility to make given movements, we consider SCARA robots much more. Unlike what happened in the past, when we need to manage a light manipulation, it becomes convenient to turn to solutions ready on the market and easy to integrate, rather than specifically designing a manipulator”.
Generally speaking, what are the most important features for the tasks that are typically required to SCARA robots? “Speed, of course. But not only”, explains Mr Rossi. “Versatility is often a key requirement in the applications we deal with. If, in fact, there is no doubt that to make a pick & place from a point A to a point B, a simple Gantry portal is enough, if the task involves greater complexity, then it becomes important to have an object that allows you to be versatile. Specifically in the collaboration with Sinta for the supply of Epson robots, another key factory for us is the wide range of solutions to choose from, which allows us to find the most suitable model for each single application”.

The machine for testing disk packs
One of these applications, the one we saw during our visit to Brugnera, is a machine designed and built for the control of disk packs for electric motors for the automotive sector.
The disk pack arrives at the machine from a press through two input belts. The first of the three Epson SCARA robots takes the workpiece and conveys it to the main rotary table, which consists of more than one station. In the first one, the workpiece is compressed and calibrated. The compression takes place with a force determined at the start and with a method that allows the vertical geometry of the workpiece to be maintained. In this stage, the height under stress is also measured, i.e. the height that results once the compression is finished and the workpiece is released.
In the second station, the piece is measured without force and it is possible to make an assessment of the so-called “spring effect”. These measurements are then analyzed and, based on thresholds set by the customer, it is possible to determine whether the component is good or not.

A cycle time of only 6 seconds
Once these first operations have been completed, a second SCARA robot picks up the piece and places it on a holder where, by means of some profilometers or a vision system, a quality check is carried out by analysing the workpiece geometry. This is useful to determine whether the part itself meets certain angular tolerances. The machine built by Tecnologika also includes a system capable to orient the piece, which will then be picked up and moved to a second rotary table, smaller than the first, where a jet of air cleans the component from impurities.
The next station is the laser marking one. Here, the data matrix of the piece is marked, reporting information on the product as well as its progressive number, indispensable for traceability issues. From here, the piece is unloaded and placed in front of a reader that checks that the marking has been done correctly with an operation that is technically defined as “grading”. The last of the three SCARA robots therefore has the task of unloading the component onto one of the four available tracks: two are for the good pieces, one for waste pieces that can be recovered and the other for those that cannot be recovered. “Control is of course a crucial stage in this process”, explains Stefano Rossi. “Both control stations we have planned on the machine use a magnetic linear encoder. The handling of the part is equally important. In this specific case, we have installed three SCARAs in order to keep cycle time very low, namely one piece checked every 6 seconds, to be exact. As a result, the ability to use multiple robots is crucial to achieving the goal. In this application, the robots are pushed to the limit of their capabilities, in terms of performance, speed and even the vibrations they have to withstand”.