Open-end spinning machine and method of operating the same

In an open-end spinning machine, a combination comprising first means for engaging a first bobbin and rotating the same at a predetermined speed in preparation for taking up a yarn thereon;

• second means for continuously advancing a yarn at a constant speed corresponding to the take-up speed, to said first bobbin so that the yarn can be wound onto the same to form a yarn package;
• third means for rotating an empty second bobbin at said predetermined speed;
• fourth means for severing the advancing yarn from the yarn package on said first bobbin, so as to form a free yarn end on the advancing yarn;
• fifth means for inserting said free yarn end substantially at the take-off speed into the interior of the rotating second bobbin for entrapping and taking up of a yarn reserve by the same, said fifth means comprising a yarn gripper movable between one position in which it engages the free yarn end, and another position in which it is located in the interior of said bobbin with said free yarn end;
• and sixth means for replacing said first bobbin having said yarn package thereon with the rotating empty second bobbin on said first means.

In an open-end spinning machine, a combination comprising first means for engaging a first bobbin and rotating the same at a predetermined speed in preparation for taking up a yarn thereon;

• second means for continuously advancing a yarn at a constant speed corresponding to the takeup speed, to said first bobbin so that the yarn can be wound onto the same and form a yarn package;
• third means for rotating an empty second bobbin at said predetermined speed;
• fourth means for severing the advancing yarn from the package on said first bobbin, so as to form a free yarn on the advancing yarn;
• fifth means for inserting said free yarn end substantially at the take-off speed into the interior of the rotating second bobbin for entrapping and taking up of a yarn reserve by the same, said fifth means comprising a yarn gripper movable between one position in which it engages the free yarn end, and another position in which it is located in the interior of said bobbin with said free yarn end;
• and sixth means for replacing said first bobbin having said yarn package thereon with the rotating empty second bobbin on said first means.

In an open-end spinning machine using tubular bobbins each having a marginal portion bounding one axial end of the bobbin and provided with a notch, a combination comprising first means for engaging a first bobbin and rotating the same at a predetermined speed in preparation for taking up a yarn thereon;

• second means for continuously advancing a yarn at a constant speed corresponding to the takeup speed, to said first bobbin so that the yarn can be wound onto the same and form a yarn package;
• third means for rotating an empty second bobbin at said predetermined speed;
• fourth means for severing the advancing yarn from the yarn package on said first bobbin, so as to form a free yarn end on the advancing yarn;
• fifth means operative for inserting said free yarn end substantially at the take-off speed into the interior of the rotating second bobbin and positioning it so that it may be caught by said notch for entrapping by said bobbin and taken up of a yarn reserve by the same;
• and sixth means for replacing said first bobbin having said yarn package thereon with the rotating empty second bobbin on said first means.

In an open-end spinning machine using tubular bobbins each having a marginal portion which bounds one axial end of the bobbin and is formed with a roughened edge, a combination comprising first means for engaging a first bobbin and rotating the same at a predetermined speed in preparation for taking up a yarn thereon;

• second means for continuously advancing a yarn at a constant speed corresponding to the takeup speed, to said first bobbin so that the yarn can be wound onto the same and form a yarn package;
• third means for rotating an empty second bobbin at said predetermined speed;
• fourth means for severing the advancing yarn from the yarn package on said first bobbin, so as to form a free yarn end of the advancing yarn;
• fifth means for inserting said free yarn end substantially at the take-off speed into the interior of the rotating second bobbin using tubular bobbins each having a marginal portion which bounds one axial end of the bobbin and is formed with a roughened edge for entrapping of the yarn by said bobbin and taking up of a yarn reserve by the same;
• and sixth means for replacing said first bobbin having said yarn package thereon with the rotating empty second bobbin on said first means.

In an open-end spinning machine using tubular bobbins each having a marginal portion which bounds one axial end of the bobbin and is provided with a protuberance, a combination comprising first means for engaging a first bobbin and rotating the same at a predetermined speed in preparation for taking up a yarn thereon;

• second means for continuously advancing a yarn at a constant speed corresponding to the takeup speed, to said first bobbin so that the yarn can be wound onto the same and form a yarn package;
• third means for rotating an empty second bobbin at said predetermined speed;
• fourth means for severing the advancing yarn from the yarn package on said first bobbin, so as to form a free yarn on the advancing yarn;
• fifth means for inserting said free yarn end substantially at the take-off speed into the interior of the rotating second bobbin and for positioning the free yarn end so that it may be engaged and entrained by said protuberance for entrapping of the yarn by said bobbin and taking up of a yarn reserve by the same;
• and sixth means for replacing said first bobbin having said yarn package thereon with the rotating empty second bobbin on said first means.

In an open-end spinning machine, a combination comprising first means for engaging a first bobbin and rotating the same at a predetermined speed in preparation for taking up a yarn thereon;

• second means for continuously advancing a yarn at a constant speed corresponding to the takeup speed, to said first bobbin so that the yarn can be wound onto the same and form a yarn package;
• third means for rotating an empty second bobbin at said predetermined speed, said third means comprising two rolls, a spring biased toggle lever mounting on each of its arms one of said rolls, a bar supporting said lever and adapted to reciprocate between one end position in which said rolls are prepared to receive the empty bobbin, at least one intermediate position in which said rolls urge said empty bobbin into motion-receiving engagement with said bobbin-driving element, and another end position in which the rotating empty bobbin is engaged by said first means;
• fourth means for severing the advancing yarn from the yarn package on said first bobbin, so as to form a free yarn end on the advancing yarn;
• fifth means for inserting said free yarn end substantially at the take-off speed into the interior of the rotating second bobbin for entrapping and taking up of a yarn reserve by the same;
• and sixth means for replacing said first bobbin having said yarn package thereon with the rotating empty second bobbin on said first means.

In a method of operating an open-end spinning machine, the steps of continuously advancing a yarn towards a takeup station at a constant speed corresponding to the takeup speed;

• winding the advancing yarn at said station onto a bobbin which rotates at a predetermined speed so that a yarn package is formed on the bobbin until the latter is full;
• rotating an empty bobbin and accelerating it to said predetermined speed;
• severing the advancing yarn from the yarn package on the full bobbin to provide a free yarn end;
• seizing said free yarn end and displacing it at a constant speed corresponding to the takeup speed to the rotating empty bobbin;
• inserting said free yarn end substantially at the takeup speed into the rotating empty bobbin at one axial end of the empty bobbin;
• entrapping the yarn at said axial end;
• looping the yarn from said axial end onto a periphery of the rotating empty bobbin;
• commencing winding of several yarn coils onto the rotating empty bobbin;
• releasing said free yarn end, and replacing the full bobbin at said station with said rotating empty bobbin.

In an open-end spinning machine, a combination comprising first means for engaging a first bobbin and rotating the same at a predetermined speed in preparation for taking up a yarn thereon;

• second means for continuously advancing a yarn at a constant speed corresponding to the takeup speed, to said first bobbin so that the yarn can be wound onto the same and form a yarn package;
• third means for rotating an empty second bobbin at said predetermined speed;
• fourth means for severing the advancing yarn from the yarn package on said first bobbin, so as to form a free yarn end on the advancing yarn;
• fifth means for seizing said free yarn end and displacing it at a constant speed corresponding to the takeup speed to the rotating empty bobbin, and for thereupon inserting said free yarn end substantially at the take-off speed into the interior of the rotating second bobbin for entrapping of the yarn by the same, looping of the yarn from said axial end onto the bobbin periphery and winding of several yarn coils onto the periphery prior to release of said free yarn end;
• and sixth means for replacing said first bobbin having said yarn package thereon with the rotating empty second bobbin on said first means.