Guides smooth the way to real coffee

A THK product story

Edited by the Engineeringtalk editorial team Apr 15, 2003

Compact linear guides are a crucial component in a novel approach to coffee making.

Combining all the advantages of a perforated bag, but with fresh filter coffee, Molins ITCM's Cafusa coffee bag is set to revolutionise coffee breaks forever.

Key to the development of the revolutionary cuppa is THK's compact linear guides.

"The real achievement is bringing a novel concept to market".

Euan Seaton, Project Engineer at Molins ITCM, is justifiably proud of his involvement in the ground-breaking Cafusa coffee bag and the associated production machinery.

"Nobody has ever built anything like this before", he notes.

The Cafusa coffee bag, with patented Pour-Thru technology, was developed entirely by Molins ITCM, a Coventry-based firm more accustomed to providing bespoke engineering solutions for large blue-chip companies than pouring the perfect filter coffee.

However, the project also required the development of specially designed machinery, which crucially relied on THK's linear motion guides.

"THK's linear motion guides are an important part of the Cafusa machine and provide us with superb reliability and minimum downtime", Seaton says.

"They're an integral part of the process".

The Cafusa machine utilises four RSR miniature linear motion guides and two SHS guides, incorporating Caged Ball technology.

The compact guides are used to progress product through the system, which produces 75 bags a minute.

More specifically, the SHS units are fitted with gripper assemblies that pull accurate lengths of bag and sachet material into the machine during each cycle.

Meanwhile, the RSRs are used to advance nine coffee bags simultaneously.

"We give the Cafusa machine the materials - the paper, the cardboard tags and the sachet-film wrap - and it makes and fills the bags and overwraps them in the sachet material".

Like all ground-breaking ideas, it's insightful and delightfully simple.

THK's linear motion guides follow this precedent by providing smooth movements from lightweight and compact designs.

At Molins ITCM, THK's ability to deliver practical as well as efficient linear guides has earned the Milton Keynes-based component supplier notable praise.

"We use THK because they have a good reputation and they've never let us down", explains Seaton.

"For example, during the Cafusa project, we wanted low-mass linear motion guides capable of providing long operating lives.

We specified the RSR, which has a higher load rating than many competing systems, which meant we could drop down a size and gain a weight advantage.

This reduced the forces generated during acceleration and deceleration and meant smaller machine parts - including smaller cams and levers - were possible".

THK's linear motion guides also ensured high levels of efficiency through ultra-smooth movements, which reduced the threat of web breaks.

"Since bag and sachet materials are pulled through the machine using the SHS guides, the 'pull' needs to be smooth without acceleration peaks as this would snap the web.

THK's linear motion guides provide this smoothness".

The development of the Cafusa coffee bag represents a noticeable departure from the Coventry-based firm's traditional role of supplying bespoke engineering solutions.

Now, with its own product incorporating THK's compact and ultra-smooth linear motion guides, Molins ITCM is developing a reputation as a coffee bag specialist.

Seaton concludes: "It's very important and exciting that we have a product we can sell.

Everybody's waiting to see what happens, but so far Cafusa has met or exceeded our sales expectations.

THK's linear guides have been an important part of this".