Tower SMD storage Saves More Than 15mins per Job

Locarno on Lake Maggiore, Ticino, Switzerland: This is the place where the control systems for the famous Schindler elevators originate. Every PCB in all its elevators all over the world are developed and produced here. Engineers are continuously improving and testing new circuits and trying out new functions. That is why the electronics development department is equipped with its own electronics prototype laboratory with the most flexible production machines from Essemtec. The only problem is that both engineers and laboratory technicians must have access to the SMD components.

Formerly, all components were simply stored on a shelf. Without control of the input and output, there was constant component anarchy. The laboratory technicians were always missing SMDs for production because the reel had been taken by someone for experiments. Strict rules were put in place that improved the situation only temporarily. With the constantly growing production and, therefore, growing time for searching for the troublesome components, the situation was no longer acceptable.

Electronics development team leader Marco Antoniutti had only two choices to get the clear component order that he wanted. Either all components were rigorously closed-in and managed from one person only, or an automatic storage system is implemented where only authorized persons would have access. But when Marco Antoniutti got to know the Tower SMD storage system from Essemtec, he immediately knew that this would solve all the problems at once.

The Tower is a sealed storage system in which a robotic arm handles reels and trays, stores them and provides them (if required). Within a few seconds, it can retrieve any of the components stored inside and pass it to the user. Placing components into the storage is also simple: The user must only place the reel onto the input table, the rest is done automatically by the tower. It reads the barcode on the reel, stores the reel in any of the free slots and memorizes the transaction. The system is secure and simple, there is no possibility for user errors.

When Schindler introduced its first tower in 2008, it quickly became very popular. Engineers could now get themselves the required components ― and quickly due to the easy-to-use software. They also returned the components voluntarily because the storage process was so simple. This also had the benefit of making the laboratory technician’s life much easier.

Previously, each component reel had to be searched for on the storage shelf, but the Tower automatically hands out all required components individually. If a specific reel or tray is not in the tower, it is clear where to find it because every transaction requires user identification. The Tower has brought the required order to the electronics development laboratory of Schindler Elettronica SA and it has saved both time and money. In 2010, Schindler installed a second Tower next to its first one.

Microdul AG is another electronics manufacturer that uses two Tower storage systems. The difference is that it uses it in production. Microdul produces customized miniaturized electronics modules. A significant part of its products are made for customers in the medical industry. Therefore, quality is absolutely crucial for the company’s customers, and all process steps and materials must be documented. Lot sizes are between 50 and 2000 pieces per job, which provided enormous logistical concerns until the Tower was introduced.

Before the Tower, Microdul used the classic storage and setup concept for SMD components: All parts were stored in the basement, packed into boxes according to part lists, and then sent up three stairs to the production floor. After assembly, the reels and trays went back into the boxes and down to the basement storage. Actually, this is a simple and clear system and it could even be successful, if the components were not required on multiple jobs.

If, as an example, a 270k/0603 resistor was required on multiple boards at the same time, it was only packed into one of the job boxes. A remark was added to the other part lists so the operator would know where to look for it. However, because of human error, operators spent a lot of time searching for components, calling, and going up and down between the basement and production floor. It was not until 2008 when these problems disappeared. This is when the first Tower was installed just a few meters from the pick-and-place machine.

Urs Merki, production manager at Microdul, said that the decision to use the Tower storage system was an easy one. The fact that it could be installed next to the placement machine was the deciding factor. For the investment application, he had calculated setup and storage time savings of 15 minutes for each job. Therefore, he calculated an ROI (return on investment) of less than one year. Today he is convinced that these values were too pessimistic, and that the Tower brings more savings and higher added values than he expected. However, it did not start out this way.

“Again another computer,” was the first statement from production staff when the Tower was installed. In the beginning, operators avoided using the new system and used arguments such as “We have so many reels of this component that we better keep them in the basement and not block the new Tower.” Therefore, it was not used and, consequently, increased the logistical problems instead of reducing them. But the more the components ound their way into the Tower, the more the acceptance and enthusiasm of the staff grew. With the Tower, they now spent less time searching, could setup machines more reliably and produce faster. A second Tower was installed to double capacity.

The Tower has been integrated into Microdul’s logistics network, which was less a problem for the Tower than for the Juki pick-and-place system. “The Tower is very communicative”, says Urs Merki and commends the open interface of the Tower, which can easily be accessed. The communication with Juki’s IFS (Intelligent Feeder System) was more difficult and had to be solved by an external software company. This is because at Microdul the IFS is responsible for the part list creation, the recording of new components and the print-out of identifying barcode labels. Now, all data are automatically transmitted from the pick-and-place to the Tower so that components must only be captured once.

Microdul has both ISO9001 and ISO13485 certifications. The latter qualifies the company for the manufacturing of medical devices. The standard requires extreme care in the production and the complete recording of all production steps and materials. The Tower is prepared for this as it continuously measures temperature and humidity inside and records all component transactions. Therefore, it is possible to document the component history completely. For MSL controlled components (Moisture Sensitive Level), it is even possible to calculate the remaining floor life time.

The Tower stores up to 546 reels and trays in a compact footprint of 1 m2 and a height of 2.2 m, making it able to fit onto more production floors. Additionally, the system is modular ― multiple Towers can be lined up next to each other and managed by central software. The database has control over every component, their storage positions and their stock amount.