(19)
(11) EP 1 477 595 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
09.11.2005 Bulletin 2005/45

(43) Date of publication A2:
17.11.2004 Bulletin 2004/47

(21) Application number: 04009107.6

(22) Date of filing: 16.04.2004
(51) International Patent Classification (IPC)7: D01H 9/04, D01H 9/16
(84) Designated Contracting States:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PL PT RO SE SI SK TR
Designated Extension States:
AL HR LT LV MK

(30) Priority: 15.05.2003 JP 2003137292

(71) Applicant: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
Kariya-shi, Aichi-ken (JP)

(72) Inventors:
  • Yakushi, Makoto c/o Kabushiki K. Toyota Jidoshokki
    Kariya-shi, Aichi-ken (JP)
  • Niimi, Kiwamu c/o Kabushiki K. Toyota Jidoshokki
    Kariya-shi, Aichi-ken (JP)

(74) Representative: HOFFMANN EITLE 
Patent- und Rechtsanwälte Arabellastrasse 4
81925 München
81925 München (DE)

   


(54) Method of operating ring spinning machine during suspension for doffing and method of cutting yarn during doffing


(57) Disclosed are a method of operating a ring spinning machine during suspension for doffing and a method of cutting yarn during doffing. There is provided a drafting device allowing draft ratio change independently of the driving of a spindle drive system. Prior to forming an oblique winding on cop during suspension for doffing, the draft ratio of the drafting device is changed so as to be larger than the draft ratio of the spinning conducted until then without changing the number of twists to perform the operation during suspension for doffing. By increasing the degree to which the rotating speed of a back bottom roller is reduced, the draft ratio is increased. The number of twists of the yarn forming the oblique winding remains the same while the yarn becomes thinner, so that, when doffing is performed by a doffing device, it is possible to cut the tail yarn at a tail yarn cutting portion so as to attain a short yarn end.






Search report