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:
Jun. 26, 1990
Filed:
Feb. 10, 1989
Fiorenzo Ghiardo, Vigliano Biellese, IT;
Roj Electrotex S.p.A., Biella, IT;
Abstract
A method and apparatus to adjust the motor speed in yarn feeders for textile machines and, in particular, weft feeders for weaving looms, wherein a yarn reserve is wound on a rotary drum held stationary, by a winding arm rotated by the motor. Photoelectric cells positioned close to a yarn outlet end of the drum emit signals which adjust--in cooperation with detection of the rotations of the winding arm--the motor speed of the feeder. These signals differ from each other according to whether an advancing turn of the yarn reserve intercepts a luminous beam for a relatively long period of time or whether yarn drawn from the reserve by the loom intercepts a luminous beam for a relatively short period of time. These signals are discriminated so as to adjust said speed, so as to guarantee the constant presence of an adequate yarn reserve on the drum.