Patent ID: 6095449
Filing Date: 2000-08-01
Classification: B65H,D02H,D03D,G01L

Abstract:
A device for controlling tension of a yarn at the outlet of a yarn feeder provided with a drum about which a reserve of yarn windings are disposed for feeding the yarn into a weaving machine, said device comprising:an eyelet disposed coaxially with an axis defined by the drum for guiding the yarn along the drum axis towards the weaving machine as the yarn is drawn off of the reserve, said eyelet being movable along the drum axis and the yarn extending through the eyelet and exerting a first force thereon which is proportional to the yarn tension and which is oriented along the drum axis; anda yarn tension measuring arrangement including a control circuit, a position sensor, and an electromagnetic control to which current is supplied by said control circuit, said electromagnetic control having a movable control element operable electromagnetically and connected to said eyelet for movement therewith, said position sensor communicating with said control circuit and providing a signal thereto upon displacement of said movable control element from a predetermined measuring position and corresponding to displacement of said eyelet along the drum axis as a result of said first force, said control circuit providing said electromagnetic control with current in response to said signal from said position sensor such that said electromagnetic control generates a second force which moves said movable control element to balance said first force and maintain said movable control element substantially motionless in said predetermined measuring position during variations in the yarn tension, said tension measuring arrangement including means for measuring said current and generating a signal which corresponds to the yarn tension.