Method and apparatus for start-spinning a thread on an open-end spinning unit of an open-end spinning machine

An apparatus for start-spinning a thread on an open-end spinning unit of an open-end spinning machine, having a mobile start-spinning unit with means for returning an end of the thread to a spinning rotor, for placing said end of the thread on a ring of fibres located in said spinning rotor and for drawing off the start-spun thread again, as well as means for reducing the speed of said spinning rotor relative to its operating speed, and means which intervene in one of drive means and control means providing the feed of the sliver forming said fibre ring for the purpose of reducing the rate of said formation of said fibre ring, wherein a common mechanical drive means is provided for rotatably driving spinning rotors of a plurality of said spinning units, and wherein said means which intervene include means for interrupting the rotatable drive of one of said spinning rotors without interrupting the rotatable drive of the other of said commonly driven spinning rotors.

An apparatus for start-spinning a thread on an open-end spinning unit of an open-end spinning machine, having a mobile start-spinning unit with means for returning an end of the thread to a spinning rotor, for placing said end of the thread on a ring of fibres located in said spinning rotor and for drawing off the start-spun thread again, as well as means for reducing the speed of said spinning rotor relative to its operating speed, and means which intervene in one of drive means and control means providing the feed of the sliver forming said fibre ring for the purpose of reducing the rate of said formation of said fibre ring, wherein said means for placing said end of the thread and said means for reducing the speed of said spinning rotor relative to its operating speed are constructed and synchronized such that said thread is returned to said spinning rotor and placed on said ring of fibres during acceleration of said spinning rotor from a previously braked condition to its operating speed.

An apparatus for start-spinning a thread on an open-end spinning unit of an openend spinning machine, having amobile start-spinning unit with means for returning an end of the thread to a spinning rotor, for placing said end of the thread on a ring of fibres located in said spinning rotor and for drawing off the start-spun thread again, as well as means for reducing the speed of said spinning rotor relative to its operating speed, and means which intervene in drive means providing the feed of the sliver forming said fibre ring for the purpose of reducing the rate of said formation of said fibre ring, in which said start-spinning unit contains a driving wheel which, through adjustment, can be coupled with a corresponding drive wheel of the drive means associated to the open-end spinning unit for the feed of said sliver.

An apparatus for start-spinning a thread on an open-end spinning unit of an openend spinning machine, having a mobile start-spinning unit with means for returning an end of the thread to a spinning rotor, for placing said end of the thread on a ring of fibres located in said spinning rotor and for drawing off the start-spun thread again, as well as means for reducing the speed of said spinning rotor relative to its operating speed, and means which intervene in drive means providing the feed of the sliver forming said fibre ring for the purpose of reducing the rate of said formation of said fibre ring, in which an auxiliary drive of the start-spinning unit has freewheeling means.

An apparatus for start-spinning a thread on an open-end spinning unit of an open-end spinning machine, having a mobile start-spinning unit with means for returning an end of the thread to a spinning rotor, for placing said end of the thread on a ring of fibres located in said spinning rotor and for drawing off the start-spun thread again, as well as means for reducing the speed of said spinning rotor relative to its operating speed, and means which intervene in control means providing the feed of the sliver forming said fibre ring for the purpose of reducing the rate of said formation of said fibre ring, in which, through transmission means of the start-spinning unit, a thread stop-motion connected with a reversing switch is caused to interrupt a stationary drive for feeding the sliver.

An apparatus for start-spinning a thread on an open-end spinning unit of an open-end spinning machine, having a mobile start-spinning unit with means for returning an end of the thread to a spinning rotor, for placing said end of the thread on a ring of fibres located in said spinning rotor and for drawing off the start-spun thread again, as well as means for reducing the speed of said spinning rotor relative to its operating speed, and means which intervene in drive means providing the feed of the sliver forming said fibre ring for the purpose of reducing the rate of said formation of said fibre ring, in which the sliver is fed by means of a feed roller, which, under normal operating conditions, is pressed against a drive shaft extending over a plurality of spinning units and which, in the event of a thread break, is lifted off the drive shaft by an actuating element which is electrically connected with a thread stop-motion, and is pressed against a roller which is driven by a driving wheel of the start-spinning unit.

An apparatus for start-spinning a thread on an open-end spinning unit of an open-end spinning machine, having a mobile start-spinning unit with means for returning an end of the thread to a spinning rotor, for placing said end of the thread on a ring of fibres located in said spinning rotor and for drawing off the start-spun thread again, as well as means for reducing the speed of said spinning rotor relative to its operating speed, and means which intervene in control means providing the feed of the sliver forming said fibre ring for the purpose of reducing the rate of said formation of said fibre ring, in which the start-spinning unit contains intermittently operating switching means which can be connected with the switching means of a clutch which is associated to the sliver feed and which can be switched on and off.

An apparatus for start-spinning a thread on an open-end spinning unit of an open-end spinning machine, having a mobile start-spinning unit with means for returning an end of the thread to a spinning rotor, for placing said end of the thread on a ring of fibres located in said spinning rotor and for drawing off the start-spun thread again, as well as means for reducing the speed of said spinning rotor relative to its operating speed, and means which intervene in control means providing the feed of the sliver forming said fibre ring for the purpose of reducing the rate of said formation of said fibre ring, in which said start-spinning unit contains switching means which can be coupled to trapping means, associated to each spinning unit, for interrupting the sliver feed, said switching means permitting said trapping means to be switched either on or alternatively on and off at predetermined time.

An apparatus for start-spinning a thread on an open-end spinning unit of an open-end spinning machine, having a mobile start-spinning unit with means for returning an end of the thread to a spinning rotor, for placing said end of the thread on a ring or fibres located in said spinning rotor and for drawing off the start-spun thread again, as well as means for reducing the speed of said spinning rotor relative to tis operating speed, and means which intervene in drive means providing the feed of the sliver forming said fibre ring for the purpose of reducing the rate of said formation of said fibre ring, in which said start-spinning unit contains an auxiliary brake which can be coupled with the means for feeding the sliver.

An apparatus for start-spinning a thread on an open-end spinning unit of an open-end spinning machine, having a mobile start-spinning unit with means for returning an end of the thread to a spinning rotor, for placing said end of the thread on a ring of fibres located in said spinning rotor and for drawing off the start-spun thread again, as well as means for reducing the speed of said spinning rotor relative to its operating speed, and means which intervene in control means providing the feed of the sliver forming said fibre ring for the purpose of reducing the rate of said formation of said fibre ring, in which said start-spinning unit contains intermittently operating switching means which intervene directly from the outside in trapping means which interrupt the sliver feed and which intermittently interrupt said trapping effect.