Patent ID: 7043893

Claim:
A device for spinning a yarn from a loose fibre structure with the aid of a swirl flow, said device comprising: a fibre delivery channel through which fibres of said loose fibre structure travel, said fibre delivery channel defining an outlet aperture; a yarn extraction channel defining an inlet aperture positioned at a known distance from said outlet aperture of said fibre delivery channel, said yarn extraction channel receiving said yarn through said inlet aperture as said yarn is being spun; a swirl chamber arranged between said outlet aperture of said delivery channel and said inlet aperture of said yarn extraction channel, said swirl chamber receiving a fluid that creates a swirl flow within said swirl chamber; at least two nozzles disposed tangentially to said swirl chamber, said nozzles feeding said fluid to said swirl chamber to create said swirl flow; an outlet channel disposed to said swirl chamber for conducting said fluid out of said swirl chamber, said outlet channel forming an anular cross-section; and a guide surface radially extending in a collar fashion around said inlet aperture of said yarn extraction channel and connecting to said outlet channel so that said guide surface forms an angle with an axis of said yarn extraction channel in a direction of yarn travel, said guide surface having a radial extension from said inlet aperture to said outlet channel of at least one-tenth of an effective staple length of the fibres to be processed and delimiting the swirl chamber downstream to guide fibres or fibre sections swirling in said swirl flow.