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50th anniversary of USTER® yarn clearers for automatic winding machines

From simple beginnings in 1952, the story of USTER® yarn clearing technology has today arrived at an unimaginable peak, with the latest USTER® QUANTUM 3 systems featuring Smart Clearing Technology.




It was Zellweger Uster, the forerunner of the company which became Uster Technologies in the 21st Century, which took the first steps in yarn quality checking during winding. The original yarn clearing device, patented as a ‘slub-catcher’ in 1952, was a mechanical system for use on manual winders. It reached the market three years later.

Electronic yarn clearing was a notable development stage. The USTER® SPECTOMATIC electronic yarn clearer for manual winding machines won industry approval, being retrofitted to winders made by Savio, Schlafhorst, Poron Rop, Schweiter, Mettler and others from 1960 on.

USTER® AUTOMATIC UAM B1 – golden jubilee yarn clearer
A major breakthrough happened in 1965, when the USTER® AUTOMATIC UAM B1 clearer hit the market. This was the first yarn clearer designed for automatic winding machines – an innovation which has its golden jubilee this year. The UAM B1 was eventually fitted to the leading automatic winders of the day, including the Schlafhorst Autoconer AC 107, Gilbos Conematic, Müller Automat, Barber Colman CC, Schweiter CA11 and Leesona Uniconer. 

In 1970, the next development arrived with the USTER® AUTOMATIC UAM C1, which had an important extra feature over the UAM B1: a ‘thin place adapter’ allowing it to eliminate disturbing faults of both thick and thin types.

The advent of microprocessors was quickly seized upon by USTER technologists as the catalyst for further new ideas in yarn clearing. The USTER® POLYMATIC UPM 1 was the first example in 1985, also featuring the NSLT classification model still used today for neps, short thick, long thick and thin places.

Foreign fiber sensation, and onwards…
In 1995, the long-standing problem of foreign matter contamination in yarn was tackled by the USTER® PEYER CLEARER UPC 2OO. This was launched two years after the Peyer company was acquired by Zellweger Uster, as the first clearer able to detect foreign fiber based on an optical principle which could simultaneously pinpoint disturbing thin places, thick places and foreign fibers.

The first generation USTER® QUANTUM clearers combined a capacitive sensor and a foreign matter sensor what was regarded as a sensational innovation. The following version, the USTER® QUANTUM 2 also heralded a new era in detection capabilities, now taking white polypropylene as the first yarn clearer ever. Developments have brought us to the age of ‘data-driven’ yarn clearing, thanks to the YARN BODY concept created with the latest USTER® QUANTUM 3. This chapter of the story about setting clearing limits at a single touch of a button and much more is well known – or to be read here.