Friction yarn false twisting apparatus

US4803915A · kind A · utility

Assignee

• Barmag AG · DE

Inventor

• Detlev Oberstrass · Neviges, DE

Key dates

• Filing date: Mar 9, 1987
• Grant date: Feb 14, 1989
• Expiry date: Mar 9, 2007

Classification

• Technology area (CPC D): Textiles; Paper
• CPC primary: D02G1/085
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

Abstract

A yarn false twisting apparatus is disclosed which comprises a pair of rotating circular discs having cooperating friction surfaces for engaging a running yarn at a twisting zone. A pressure applying member is positioned to apply a biasing force to the rear surface of one of the discs locally at the twisting zone, and the pressure applying member comprises a receptacle slideably mounting a piston which extends from the end of the receptacle to engage the disc. The receptacle is eccentrically mounted to permit selective positioning of the biasing force with respect to the yarn path of travel. The discs are mounted on pivotal rocking arms whereby the ratio of yarn twist to yarn speed may be adjusted, and an eccentrically mounted pin provides closely controlled adjustability for the arms and thus the twist ratio. The apparatus may be readily configured to provide either S or Z twist, and the drive system may be disengaged while in either the S or Z twist configuration to terminate rotation of the discs and thereby facilitate yarn thread-up.