Method for graduated precision winding of a textile yarn cheese

• US 20020040946A1
• Filed: 03/30/2001
• Published: 04/11/2002
• Est. Priority Date: 03/30/2000
• Status: Active Grant

• Current Assignee: Saurer Germany GmbH & Co., KG
• Original Assignee: W. Schlafhorst AG & Co. (OC Oerlikon Corporation AG)
• Inventors: Lassmann, Manfred
• Granted Patent: US 6,484,962 B2
• Time in Patent Office: Days
• US Class Current: 242/477.5
• CPC Class Codes: B65H 2515/12 Density
• CPC Class Codes: B65H 2701/31 Textiles threads or artificial strands of filaments
• CPC Class Codes: B65H 54/08 Precision winding arrangements
• CPC Class Codes: B65H 54/383 in a stepped precision winding apparatus, i.e. with a constant wind ratio in each step
• CPC Class Codes: D01H 4/40 Removing running yarn from the yarn forming region, e.g. using tubes

Abstract

A method for producing graduated precision windings on cheeses in an open-end spinning system. The winding ratio is reduced in stages, in increasingly smaller graduations, as the cheese diameter increases during the bobbin travel of the cheese. The graduations do not exceed the value of 0.3 and are each selected such that changes in the crossing angle are within a tolerance range of less than ±O.8°, and the least number of diamonds occurring during the building of the bobbin can be completely filled. The cheeses thusly produced are distinguished by a stable construction, high density with uniform distribution of density over the entire yarn package, and excellent payout properties.

Claims

1. In an open-end spinning system, a method for graduated precision winding of a staple fiber yarn fed at a constant yarn speed onto a cheese rotating at constant circumferential speed, wherein the winding ratio during progressive building of the cheese is reduced in stages by graduations of decreasing size as the diameter of the cheese increases, each such graduation decreasing the winding ratio by a value not exceeding 0.3, and each such graduation decreasing the winding ratio being selected to be sufficiently small to produce a change in a crossing angle of the yarn during winding of between about ±

0.8°

of a predetermined set-point value for the crossing angle and selected to be sufficiently large to completely fill a smallest number of yarn winding diamonds occurring in the respective yarn winding stage.

2. The method of claim 1, characterized in that each graduation is selected to produce a change in the crossing angle of between about ±

0.5°

of the set- point value of the crossing angle.

3. The method of claim 1, characterized in that a graduation in a core region of the cheese is increased by a predetermined multiplier.

4. The method of claim 1, characterized in that each graduation is selected by calculating each successive winding ratio by subtracting from the then prevailing winding ratio an amount obtained by multiplying the integral component of the prevailing winding ratio by a graduation factor.

5. The method of claim 4, characterized in that the graduation factor is no greater than 0.05.

6. The method of claim 5, characterized in that the graduation factor is between 0.02 and 0.05.

7. The method of claim 1, characterized in that each graduation is selected by calculating each successive winding ratio by multiplying the then prevailing cheese diameter by a percentage factor, adding the resultant multiplication product to the prevailing cheese diameter, and converting the value of the resultant cheese diameter sum into a corresponding value for the successive winding ratio.

8. The method of claim 1, characterized in that each winding ratio is selected by adding to or subtracting from the prevailing winding ratio a supplemental step-up ratio derived from a quotient of a yarn spacing value and a number of diamonds for the prevailing winding ratio.

9. The method of claim 1, characterized in that each graduation is selected to obtain a successive winding ratio which will produce a desired known number of yarn winding diamonds.

10. The method of claim 9, characterized in that the number of yarn winding diamonds is no greater than 50.