11 years in service at Wild & Küpfer AG

Once installed, demolded millions of times

Well-established, but far from being outdated, one of the earliest Servomold unscrewing systems - the 8-fold unscrewing unit for the Swiss company Wild & Küpfer AG - has been doing its job reliably for 11 years. After more than 43 million successfully unscrewed molded parts, it is high time to tell a joint success story that continues to this day.

An innovative drive concept marks the start

The year is 2012: While Wild & Küpfer AG has already stood for complex plastic parts and assemblies of the highest quality for over 35 years, the innovative Servomold system solutions are fresh to the market and so far only in use in a handful of production halls. However, in unscrewing threads, Servomold is quickly building up a reputation for its clean, high repeat accuracy systems.

The threaded core with splined shaft profile and guide nut is the crucial component for unscrewing the polypropylene closure caps.

At the Euromold trade show in 2011, the experts at Wild & Küpfer AG first become aware of the solutions offered by the company from Odenwald, Germany, and are soon ready to integrate the unscrewing devices, which are operated by servo motors, into a mold. For this purpose, an eightfold unscrewing system with two fourfold unscrewing devices is ordered, the design of which is immediately convincing: The units can be fully integrated into the standard mold design without any laterally protruding parts, and the overall height of the mold half is also comparatively compact without attachments such as racks, supports or hydraulic cylinders.

The new mold meets expectations

The Servomold designers are given the green light to build the electric unscrewing unit and take on the challenge of replacing the customer’s existing solution with a system that, in addition to space-saving design, also brings numerous further optimizations: from the short unscrewing time, which reduces cycle times in the process by around 20 percent, to precise setting and monitoring of all processes, which the associated control unit and its software make possible.

In the system, which is implemented as a two-platen closure mold, the two servo drives are mounted on the top and bottom of the moving mold half on the ejector side.

And so, the new unscrewing device becomes a reality that simultaneously meets the high expectations of the customer: Thanks to the combination of unscrewing half and servo control unit, the unscrewing motion sequences can be optimized in an unprecedented way. The Swiss company, which has been striving for improvements in drives in injection mold tools and especially in unscrewing mechanisms for some time, is extremely satisfied with the new technology. Wild & Küpfer AG already summarized the strengths and advantages of the new unscrewing devices in PLASTVERARBEITER magazine in 2012:

“The mechanical and control characteristics of the servo-electrically driven unscrewing devices are convincing and represent a suitable complement to our own technical developments. We planned the use of the unscrewing unit as a forward-looking decision after thorough preparation, and this has proved to be correct.

The mold is easy to set up and put into operation. It has proven to be robust and reliable in operation. The effort for maintenance and preventive maintenance is low. Our expectations have also been more than met in terms of the cost-effectiveness of our production – we have been able to significantly reduce cycle time. In addition, we have achieved a technology gain: The unscrewing devices are suitable for use in clean rooms. This is because the system works without hydraulic oil or compressed air, and only a very small amount of lubricant is required for the mechanics.”

Project overview

Jump to the present

Servomold system holds the fort in Schmerikon

Almost exactly eleven years after installation and commissioning, the mold continues to run smoothly, apart from a few replaced wear parts such as timing belts, and demolds the same caps with proven efficiency. The opinion at Wild & Küpfer AG also remains positive and the moldmaker employees are pleased with the long maintenance intervals and the “flawless” operation since years.

Servo control unit at the Schmerikon site, Switzerland

Via the control unit, the responsible persons still have full control over the process and can freely program movements, turning speeds and end positions. While specially configured ramps guarantee tool-friendly acceleration and deceleration, the unscrewing process is monitored down to the last detail and the slightest discrepancy is directly detected.

With its smooth interaction of hardware and software, the unscrewing unit also formed an ideal foundation for further joint developments.

Configured for long-term partnerships

Numerous details and entire assemblies have undergone further design development over the years, but the functionality of our unscrewing devices remains unchanged to this day. For us, this long-term approach testifies to a successful collaboration in which we continue to work towards the ideal solution – together across companies – long after commissioning.

After all, what Servomold has in common with customers like Wild & Küpfer AG is the willingness to give developments and designs the time they need in order to design a production of plastic parts that will continue to deliver outstanding results for decades to come. Here’s to further years of smooth operation!

Portrait Thomas Meister Geschäftsführung und Entwicklung
We are particularly pleased about the good connection to the company and our long-standing contacts at Wild & Küpfer AG, who share our philosophy. Servomold would like to formally thank them for their initial trust and long-lasting loyalty.

Thomas Meister –
Managing Director Servomold