The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 11, 1992
Filed:
Dec. 18, 1990
Ralph W Nugent, Seaford, DE (US);
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
In processes of the production of thermoplastic polymer yarns, a process for controlling slippage of yarn on rolls across which there is a tension change. The yarn is advanced along pairs of rolls with the yarn contacting the rolls in successive wraps. At least one of the rolls is driven and has a changing diameter as the yarn advances between at least two of the successive wraps. The wraps contact the contact areas on the surface of the driven roll to each define a total wrap angle for the wrap. The number of wraps is selected and the diameter of the driven roll at the contact areas is selected to increase or decrease the tension while preventing a wrap angle in creep for any one of the wraps from being greater than about 90% of the total wrap angle for the wrap.