Servos boost flexibility for packaging specialist
The solution was to upgrade the pneumatic sliding tables on its machinery to modern servo technology, increasing Leser’s agility while keeping its production costs down.
The Leser Group was founed in 1937 in the Black Forest town of Lahr, Germany. With production facilities in Germany, China and the USA, the group manufactures over 70 million packaging units every year for watches, jewellery, fashion accessories, coins, gifts and promotional items.
The international market for these products is particularly demanding, with customer requirements constantly changing and evolving. Leser’s response has been to increase its number of product variants, but this raises key manufacturing challenges, most notably the need to manufacture small batch sizes cost-effectively. Meeting these requirements demands a high level of production flexibility and agility, something that can only be met by optimizing automation processes.
For decades one of the bedrocks of Leser’s manufacturing capability has been the hot stamping machines that it uses to print its packaging products. Over the years these have performed millions of duty cycles, but with the demands of modern markets continually changing, the machines were quickly becoming a limiting factor in Leser’s flexibility, with their pneumatic slide tables being increasingly problematic. As batch sizes reduced, the ratio of retooling and set-up time to actual production was becoming a major factor, and downtime due to mechanical failures was increasing. Further, production speeds were at their limit with the existing pneumatic system.
Leser commissioned a number of contractors to find a suitable way of improving the system, including retrofitting the existing pneumatic system with an upgrade. However, this upgrade option was quickly abandoned because it would have been very complex to implement and would still not have been flexible enough. After a number of other options had been examined it became clear that servo systems offered the only viable solution.
As the possibilities were examined the specifications for the new system became increasingly extensive and Leser eventually opted for a servo solution from Mitsubishi Electric. A configuration was submitted by contractor Alexander Bürkle, built around Mitsubishi servo technology along with components from other vendors to meet all of Leser’ quality, flexibility, price and performance requirements.
A prototype system built around a Mitsubishi MR-J2S-CL programmable servo amplifier and matching HC-KFS-43 servo motor was constructed, and shown to be a highly effective solution. Alexander Bürkle engineer Bernd Walter comments: “It seemed impossible that such a small servo motor would be able to deliver the required torque, but it really could.” No separate PLC was needed to control the slide table and the physical dimensions of the hardware were far smaller than the existing pneumatic system.
Tests on the prototype configuration demonstrated a number of key advantages over the existing pneumatic system. Most importantly, the servo motion travel and speed sequences could easily be programmed for the precise needs of the products being manufactured. Leser would be able to select programs with simple BCD switches, reducing setup times for different products to an absolute minimum.
With the new servo solution installed, the hot stamping system now operates with reproducible speeds, and with significant reductions in set-up time. And when the increased reliability of the modern system is factored in, overall the result is that Leser is seeing a huge increase in system availability. Not only is this enabling Leser to meet its customer requirements, but it has also allowed it to improve the bonus system for its employees
The Leser Group was founed in 1937 in the Black Forest town of Lahr, Germany. With production facilities in Germany, China and the USA, the group manufactures over 70 million packaging units every year for watches, jewellery, fashion accessories, coins, gifts and promotional items.
The international market for these products is particularly demanding, with customer requirements constantly changing and evolving. Leser’s response has been to increase its number of product variants, but this raises key manufacturing challenges, most notably the need to manufacture small batch sizes cost-effectively. Meeting these requirements demands a high level of production flexibility and agility, something that can only be met by optimizing automation processes.
For decades one of the bedrocks of Leser’s manufacturing capability has been the hot stamping machines that it uses to print its packaging products. Over the years these have performed millions of duty cycles, but with the demands of modern markets continually changing, the machines were quickly becoming a limiting factor in Leser’s flexibility, with their pneumatic slide tables being increasingly problematic. As batch sizes reduced, the ratio of retooling and set-up time to actual production was becoming a major factor, and downtime due to mechanical failures was increasing. Further, production speeds were at their limit with the existing pneumatic system.
Leser commissioned a number of contractors to find a suitable way of improving the system, including retrofitting the existing pneumatic system with an upgrade. However, this upgrade option was quickly abandoned because it would have been very complex to implement and would still not have been flexible enough. After a number of other options had been examined it became clear that servo systems offered the only viable solution.
As the possibilities were examined the specifications for the new system became increasingly extensive and Leser eventually opted for a servo solution from Mitsubishi Electric. A configuration was submitted by contractor Alexander Bürkle, built around Mitsubishi servo technology along with components from other vendors to meet all of Leser’ quality, flexibility, price and performance requirements.
A prototype system built around a Mitsubishi MR-J2S-CL programmable servo amplifier and matching HC-KFS-43 servo motor was constructed, and shown to be a highly effective solution. Alexander Bürkle engineer Bernd Walter comments: “It seemed impossible that such a small servo motor would be able to deliver the required torque, but it really could.” No separate PLC was needed to control the slide table and the physical dimensions of the hardware were far smaller than the existing pneumatic system.
Tests on the prototype configuration demonstrated a number of key advantages over the existing pneumatic system. Most importantly, the servo motion travel and speed sequences could easily be programmed for the precise needs of the products being manufactured. Leser would be able to select programs with simple BCD switches, reducing setup times for different products to an absolute minimum.
With the new servo solution installed, the hot stamping system now operates with reproducible speeds, and with significant reductions in set-up time. And when the increased reliability of the modern system is factored in, overall the result is that Leser is seeing a huge increase in system availability. Not only is this enabling Leser to meet its customer requirements, but it has also allowed it to improve the bonus system for its employees