WO2020225705A1

WO2020225705A1 - Method for replenishing yarn supplies in a yarn storage device of a textile machine and a yarn storage device provided for this

Info

Publication number: WO2020225705A1
Application number: PCT/IB2020/054204
Authority: WO
Inventors: Koen Bruynoghe; Bram Vanderjeugt; Michiel PARMENTIER; Dominique Maes
Original assignee: Vandewiele Nv
Priority date: 2019-05-04
Filing date: 2020-05-04
Publication date: 2020-11-12
Also published as: BE1027254B1; BE1027254A1

Abstract

The present invention relates to a method for replenishing yarn supplies that are placed on bobbins at primary locations (P1-P4) of a yarn storage device (100), wherein a non-full bobbin (1-4) is moved to a secondary location (S1-S4), the yarn (21) is taken up from the moved bobbin (1-4), a new bobbin (1N-4N) is placed at the now vacant primary location (PI) and the yarn ends (41b, 51a) of the yarn on the new bobbin (1N-4N) and the yarn on the moved bobbin (1-4) are joined. The invention also relates to a yarn storage device (100) provided for implementing this method.

Description

METHOD FOR REPLENISHING YARN SUPPLIES IN A YARN STORAGE DEVICE OF A TEXTILE MACHINE AND A YARN STORAGE DEVICE

PROVIDED FOR THIS The present invention relates to a method for replenishing yarn supplies in a yarn storage device in which several yam supplies in the form of bobbins wound on respective bobbin holders are placed at respective locations, while yarns are taken up from these supplies by a machine for the patterned production of textile products, wherein replenishing a yarn supply involves providing a new bobbin with a new yarn supply at a primary location in the yam storage device.

The present invention also relates to a yam storage device for a machine for the patterned production of textile products, in which several yam supplies in the form of bobbins wound on respective bobbin holders are placed at respective locations. In this patent application, the term "textile machine" is used in the meaning of a machine for the patterned production of textile products.

In the mechanized production of textile products it is often necessary to process a large number of different yarns. A supply of each yam must be available, and the textile machine must be able to take up the yam continuously from this yarn supply as the production process proceeds. When textile products are produced that have a pattern, a drawing or a figure (such production is indicated in this patent application by the term "patterned production"), yam consumption is often irregular and in addition also different for the different yams. Therefore a common yam supply, for example such as a warp beam, from which all warp yams are released at the same speed, is in many cases unsuitable. Respective yam supplies must then be provided for the different yams, for example in the form of a bobbin, where yam is wound on a bobbin tube or a bobbin core and from which each yam can be taken up individually by the textile machine.

Thus, for example in multicoloured weaving and tufting of carpet with cut pile or loop pile, large numbers of pile yams of different colours must be supplied to the weaving or tufting device. The consumption of these pile yams depends on the design of the carpet and so is usually non-uniform and non-identical for each pile thread in the fabric. Therefore the yarn storage device must comprise a separate yarn supply for each different pile yarn. In the case of weaving machines it is known to achieve this by drawing the different yams from respective bobbins, which are mounted rotatably in a bobbin creel. Because the yams are pulled in the direction of the textile machine, the bobbins rotate, so that the yam is unreeled therefrom. A bobbin creel of this kind must often comprise many thousands of bobbins. Each bobbin has a respective location where there are means for rotatable mounting of the bobbin in a position of use for supplying the yarn supply to the textile machine. Bobbin creels of this kind are often also provided on other textile machines, such as certain tufting machines and knitting machines.

A drawback of the known bobbin creels is that they take up a lot of space in the vicinity of the textile machine.

Usually it is not possible to provide a yam supply that is large enough for the whole production process for each yarn in a bobbin creel. Therefore the yarn supplies must be replenished regularly. For replenishing a yam supply, in each case the bobbin whose yarn supply is nearly used up must be taken from the bobbin creel and a new full bobbin with a new supply of the relevant yam must be placed at the now vacant location of the removed bobbin, and the yam running from the original bobbin to the textile machine must be cut through, and the free end of the yam running to the textile machine must be knotted onto the end of the yam on the new bobbin. The yarn must then also be inserted in a yarn guide and finally tension must be applied to the yarn again, for example by placing weights on it.

In order to have sufficient time for all these actions, with this method it is necessary to replace the bobbins even before the yam wound thereon is completely used up. This results in a good deal of yam loss. The yam that is left on different bobbins may admittedly be knotted and reused, but there is then the drawback that the yarn has relatively many knots. When the textile machine is stopped to replenish the yarn supplies, this is very detrimental for the productivity and overall profitability of the weaving machine. Owing to the irregular and unequal yam consumption it is also very difficult to work according to a schedule. Because textile machines are reaching ever higher production speeds, it is also increasingly difficult to replenish yarn supplies while the textile machine is operating.

With certain tufting machines, bobbin creels are provided where two identical bobbins with the relevant yarn are provided per yam supply in the bobbin creel. These are non rotating bobbins, from which the yam is unwound from the top of the bobbin. In this way, a double yarn supply may be provided per yam, so that for each yarn it is possible to wait until the yarn of one of the two bobbins is used up and yarn is being taken from the second bobbin, before replacing the empty bobbin with a new one. However, there is the drawback that a bobbin creel of this kind takes up twice as much space.

Another known yarn storage device is described in EP 2 721 204 B1 and comprises individual yarn supply spaces in which loose yam supplies are provided, wherein a yarn loader is provided for connecting an end part of a yam supply to an end part of an external yarn supply and to add a quantity of yam in said yam supply space, wherein the yarn to be added is first wound onto a winding body and is then added in the wound state in the supply space. This known device makes it possible to automate the time- consuming and labour-intensive operations in the bobbin creel, but is not suitable in circumstances where larger yam supplies are preferred, in the form of bobbins wound on bobbin holders, for example in order to reduce the number of knots in the yarn. Economic considerations may also mean that in certain circumstances, for example with a large number of different yam supplies and at a high consumption rate of the yarn, a yarn storage device in which the yam supplies are provided in the form of bobbins is preferred.

One aim of the present invention is to overcome the aforementioned drawbacks by providing a method for replenishing yam supplies that are provided in the form of bobbins wound on bobbin holders in a yam storage device, and by providing a yarn storage device in which yarn supplies are provided in the form of bobbins wound on bobbin holders, with which the continuity of the production process of an associated textile machine may be guaranteed, which also allows working very systematically in the replenishing of yarn supplies, with which any yam loss may be avoided, with which the number of knots in the yam per fabric may be kept very limited, and which in addition also allows a very compact design of the yam storage device.

These aims are achieved by providing, according to the present invention, a method for replenishing the yarn supplies in a yam storage device in which several yarn supplies in the form of respective bobbins wound on bobbin holders are placed at respective primary locations, while yarns are taken up from these supplies by a machine for the patterned production of textile products, wherein replenishing of a yarn supply involves providing a new bobbin with a new yam supply at a primary location in the yarn storage device, and wherein, according to the present invention, a yarn supply is replenished by moving a non-full bobbin that contains the yarn supply to be replenished, from its primary location to a secondary location in the yarn storage device, so that the yarn may further be taken up by the machine in operation from this moved bobbin, placing the new bobbin at the now vacant primary location, and connecting an unwinding end of the yam present on the new bobbin to an end of the yarn present on the moved bobbin, so that, after the yam has been taken up on the moved bobbin, the yarn is further taken from the new bobbin.

The term "bobbin holder" is used in the sense of an object on which a quantity of yarn may be wound, and on which the yam windings may be held so that it can function as a carrier for the yarn windings. It is preferably an elongated element such as for example a tube with an essentially cylindrical shape made of a light material, for example such as plastic or card.

The term "bobbin" refers to the yam supply wound on a bobbin holder. The successive windings of a bobbin are wound concentrically with a common winding axis on the bobbin holder. Preferably several layers of windings are also provided on top of one another, so that a bobbin comprises an approximately tubular assembly of yarn windings, the inside of which is adjacent to the bobbin holder and the outside forms the external surface of the bobbin. A "full bobbin" is a bobbin that still contains almost the complete initial yarn supply or from which no yam or hardly any yarn has been taken. A non-full bobbin is a bobbin from which a non-negligible portion of the initial yarn supply has already been taken. A full bobbin and a non-full bobbin differ from one another in that they have a different bobbin diameter or in that they have different volumes. When for example bobbins are provided in a yam storage device that have an initial diameter D as standard, then it can be defined that a bobbin is regarded as a full bobbin when the bobbin diameter is equal to the initial diameter D or is at least 95% of the initial diameter D. A bobbin is then regarded as a non-full bobbin if the initial diameter is less than the initial diameter D, or is less than 95% of the initial diameter D. It may for example also be defined that a non-full bobbin has a bobbin diameter that is 75% less, preferably is less than 50%. A typical initial diameter is about 320 mm or 250 mm or 200 mm or intermediate dimensions. A full bobbin and a non-full bobbin may similarly be defined on the basis of a bobbin parameter other than the bobbin diameter, for example such as the volume occupied by the yam or the weight of the bobbin, the length of the yam that has been unwound from the bobbin or the thickness of the yarn layer on the bobbin, measured from the outside diameter from the bobbin holder. It may for example also be defined that a non-full bobbin has a bobbin diameter wherein the remaining yam layer thickness on the bobbin is less than 75%, is preferably less than 50%, and still more preferably is less than 30% of the initial yarn layer thickness of the full bobbin. In a greatly preferred method, a non-full bobbin is defined as a bobbin with a diameter wherein the remaining yarn layer thickness is less than 10% of the initial yam layer thickness, and for example even less than 5% of the initial yarn layer thickness.

The bobbin diameter wherein the remaining amount of yam has reached a certain percentage is found approximately by taking said percentage from the difference between the outside diameter and the inside diameter (the diameter of the bobbin holder) of the bobbin and then adding back the diameter of the bobbin holder. If the bobbin holder is a cylindrical element with a diameter dl and the bobbin has an initial outside diameter d2, then the bobbin diameter wherein the remaining yam layer thickness is still about 5% is equal to: [(d2-dl) x 0.05] + dl.

A typical initial diameter of a bobbin is about 320 mm or 250 mm or 200 mm or other dimensions that lie between 200 mm and 320 mm. A typical diameter for a cylindrical bobbin holder is about 78 to 82 mm. Hereinafter, the term bobbin also refers to the whole of the bobbin - the yarn supply - and the bobbin holder on which this yam supply is wound.

The term "location" means, in this patent application, a space in the yarn storage device that is provided with means for placing a bobbin thereon in a position wherein the yarn supply present thereon can be led to a textile machine and wherein the yarn supply can be taken up by this machine while the textile machine is operating. The terms "primary location" and "secondary location" are merely used to make a distinction between the two locations at which a bobbin may be placed, and do not indicate a difference in importance or a certain order of use of these locations, and for example are also not to be regarded as an indication of a longer or shorter time during which the bobbins would be placed at these primary and secondary locations. A location preferably also comprises holding means in order to hold a bobbin in a certain position in the yarn storage device, and guiding means for guiding the yam from the bobbin placed at the location to the textile machine. When a location is provided for unreeling the yarn from the bobbin, the holding means must be provided to hold the bobbin holder in such a way that it is freely rotatable about its longitudinal axis. Rotation preferably takes place owing to the tensile force that is exerted on the yam when it is taken up by the machine for the patterned production of textile products.

"The vacant bobbin space at a location", an expression that is used further in this patent application, means the space that may be occupied at the respective location by a bobbin that is provided with a usage configuration as a yam supply.

The size of a vacant bobbin space may be expressed on the basis of the value(s) of one or more bobbin parameters relating to the size and/or volume of the largest possible bobbin that may be placed at this location in a usage configuration as a yarn supply. Such a parameter is for example a dimension of the bobbin, such as the outside diameter and/or the length thereof, or the yam layer thickness, or the volume that the bobbin occupies. Other bobbin parameters, such as e.g. the weight of the bobbin, may be such a parameter, if the volume or the size of the bobbin can be derived therefrom, whether or not in combination with other data. In the context of this patent application, such a parameter is preferably a bobbin parameter whose value changes as yarn is taken from the bobbin. A bobbin parameter whose value changes as yarn is taken from the bobbin is called a "variable bobbin parameter" hereinafter.

In the case of a bobbin of which the yam is wound in several layers on a bobbin holder, an external dimension of the bobbin is a "variable bobbin parameter" of this kind. When the successive yarn windings are wound round a common central winding axis so that the yarn volume has an essentially cylindrical external shape, the outside diameter of the yarn volume on the bobbin - called the bobbin diameter hereinafter - is a variable bobbin parameter. When the yam volume has a cylindrical external shape with a diameter varying in the longitudinal direction or has a non-cylindrical external shape, the largest outside diameter of the bobbin, or the largest transverse dimension of the bobbin in a direction perpendicular to the axis of the bobbin, is a variable bobbin parameter. The length of the bobbin, measured in the direction of the axis thereof, may also be a variable bobbin parameter for a certain type of bobbin.

When two locations have a respective vacant bobbin space with a different size, this size difference may consequently be expressed as a ratio between on the one hand a bobbin parameter of the largest possible bobbin that can be placed at the one location and on the other hand the same bobbin parameter of the largest possible bobbin of the same type that can be placed at the other location. The bobbin parameters stated in this paragraph are preferably variable bobbin parameters. In that case said size difference may be expressed as a ratio between on the one hand a variable bobbin parameter of the largest possible bobbin that can be placed at the one location and on the other hand the value that the same variable bobbin parameter of the same bobbin may have at most to be able to place this bobbin at the other location.

The aforementioned aims may also be achieved, according to the present invention, by providing a yarn storage device for a machine for the patterned production of textile products, in which several yarn supplies in the form of bobbins wound on respective bobbin holders are placed at respective primary locations, wherein the yarn storage device according to the present invention comprises at least one secondary location for the placement of a non-full bobbin, displacing means that are provided for moving a non-full bobbin from its primary location to a secondary location, so that the yam may further be taken up by the machine in operation from this moved bobbin, placing means that are provided for placing a new bobbin at the now vacant primary location, and joining means that are provided for connecting an unwinding end of the yarn present on the new bobbin to an end of the yam present on the moved bobbin, so that, after the yarn has been taken up on the moved bobbin, the yam is further taken from the new bobbin.

Said displacing means comprise for example movably mounted holding means for holding the respective bobbins in a position of use in the yam storage device, wherein the holding means are movable, for example are able to travel along a rail or some other guidance system, in order to move said holding means between a first location where the bobbin is placed at a primary location and a second location where the bobbin is placed at a secondary location. This movement may be effected manually or may be fully or partially automated, for example by means of a displacing means, such as a motor, which is controlled by a control signal that is generated by a central control unit when a sensor or monitoring device detects that a relevant bobbin parameter, for example such as the bobbin diameter, has reached a certain threshold value wherein the replenishing process must be started, wherein the respective bobbin is moved automatically by the displacing means and an optional mechanism driven thereby from the primary location to the secondary location.

Said placing means may similarly be provided to move a full bobbin, for example by means of movable holding means, either manually or at least partially automated, from a bobbin supply to the now vacant primary location and hold it there in a position of use. Once again, the automatic movement may be effected by means of a displacing means, such as a motor, which is controlled by a control signal that is generated by a central controller when a sensor or monitoring device detects that the respective primary location is free, wherein the respective full bobbin is moved automatically by displacing means and an optional mechanism driven thereby from its place in a bobbin supply to the now vacant primary location.

An unwinding end of the yarn present on the new bobbin may be joined by means of known yarn joining means, whether or not automatically, to an end of the yarn present on the moved bobbin. These yam joining means may also be operable completely manually.

After the yarn has been taken up on the moved bobbin, the yarn is further taken up from the new bobbin. The yam on a bobbin that is replaced is therefore taken up completely and used by the textile machine, before yam is taken up from the new bobbin. There is accordingly not the slightest yam loss. Because non-full bobbins may be moved at a chosen time point to a secondary location, it is in addition possible to work very systematically. The continuity of the production process is guaranteed, since a new full bobbin can always be made ready a sufficiently long time before the last yarn on a previous bobbin is used up. Because the vacant bobbin space at the secondary locations must, however, be sufficient for the placement of non-full bobbins, these secondary locations may be smaller - have a smaller vacant bobbin space - than the primary locations, where there must be sufficient vacant bobbin space for the placement of a full bobbin. Accordingly, the whole yam storage device may be of compact design. Even if both a primary location and a secondary location are provided for each bobbin, the total volume of the yam storage device is always less than double the total volume of a yarn storage device in which only primary locations are provided, for one and the same number of bobbins. A yam storage device according to the present invention may even have a volume that is only 50%, preferably 30% or 20%, greater than the volume of a yam storage device in which only a primary location is provided, for the same number of bobbins.

A yarn storage device that only comprises the features from the next paragraph and does not comprise the other features of the aforementioned yarn storage device, and so among other things is not provided with said displacing means, placing means and joining means, is a first additional object of this patent application.

Said first additional object is a yam storage device for a machine for the patterned production of textile products, in which yam supplies in the form of first bobbins wound on respective bobbin holders are placed at respective primary locations, and in which one or more yarn supplies in the form of second bobbins wound on respective bobbin holders are placed at respective secondary locations, wherein an unwinding end of the yarn on at least one first bobbin is joined to an end of the yarn on a respective second bobbin, wherein the yams from the respective bobbins are led via guiding means to a textile machine, so that the yams, during yam take-off, are unreeled from the first bobbins, and are unwound from the second bobbins in an approximately axial direction.

In a yarn storage device of this kind, one or more pairs of two bobbins are provided, which are placed respectively at a primary and a secondary location, while their yarns are joined together so that together they form a continuous yarn supply. In a yarn storage device of this kind, by unwinding the second bobbin of each pair in an axial direction, said second bobbin may be stationary during further yarn take-off, so that the yarn end of the yarn on the second bobbin can be joined easily and without any problem to the yarn on the first bobbin of the pair.

A yarn storage device of this kind is preferably a bobbin creel. The secondary locations preferably have a vacant bobbin space that is less than the vacant bobbin space of the primary locations.

A yarn storage device that only comprises the features from the next paragraph and does not comprise the other features of the aforementioned yam storage devices, and so among other things is not provided with said displacing means, placing means and joining means, is a second additional object of this patent application.

Said second additional object is a yam storage device for a machine for the patterned production of textile products, in which yam supplies in the form of first bobbins wound on respective bobbin holders are placed at respective primary locations so that their bobbin axes extend in a first direction, and in which one or more yarn supplies in the form of second bobbins wound on respective bobbin holders are placed at respective secondary locations, so that their bobbin axes extend in a second direction that is different from the first direction, wherein an unwinding end of the yarn on at least one first bobbin is joined to an end of the yam on a respective second bobbin. In a yarn storage device of this kind, one or more pairs of two bobbins are provided, which are placed respectively at a primary and a secondary location, while their yarns are joined together so that together they form a continuous yam supply. By placing the bobbins of each pair with their bobbin axes in mutually different first and second directions, the yarn storage device may be of more compact design than the existing yarn storage devices with a double yam supply of this kind.

The features of this second additional object of the patent application may be combined with one or more features of the aforementioned first additional object of this patent application.

A yarn storage device that only comprises the features from the next paragraph and does not comprise the other features of the aforementioned yam storage devices, and so among other things is not provided with said displacing means, placing means and joining means, is a third additional object of this patent application.

Said third additional object is a yam storage device for a machine for the patterned production of textile products, in which yam supplies in the form of first bobbins wound on respective bobbin holders are placed at respective primary locations, and in which one or more yarn supplies in the form of second bobbins wound on respective bobbin holders are placed at respective secondary locations, so that the bobbin axes of the first and the second bobbins extend in the same direction, wherein an unwinding end of the yarn on at least one first bobbin is joined to an end of the yarn on a respective second bobbin, and wherein the secondary locations have a vacant bobbin space that is less than the vacant bobbin space of the primary locations.

Preferably the vacant bobbin space at the secondary locations is at most 50% of the vacant bobbin space at the primary locations. Preferably yarn guiding means are provided, which are placed in such a way that the first bobbins and the second bobbins are unwound in an approximately axial direction.

The features of this third additional object of the invention may be combined with one or more features of the aforementioned first additional object according to the present invention.

All features of this first, second and third additional objects of this patent application may be combined with any combination of one or more compatible features of the yarn storage device that is further indicated in this description and in the claims.

In a preferred method, the yarn storage device is provided to unreel the yam taken up by the machine from each bobbin placed at a primary location, and to unwind it from each bobbin placed at a secondary location, in an approximately axial direction from the bobbin.

"To unwind yarn from a bobbin in a substantially axial direction" means, in this patent application, that the yarn is unwound from the bobbin by pulling it from the bobbin in a direction (called "the direction of pulling" hereinafter) that coincides with, or makes an acute angle with, the direction of the winding axis of the bobbin, so that the successive windings are therefore, during yam take-off, pulled over an end of the bobbin, whereas the bobbin is not caused to rotate by this tensile force. Said direction of pulling is preferably determined by a yam guide element, wherein the yarn extends almost in a straight line from the bobbin to the yam guide element. The yarn guide element is preferably placed in such a way that the yam is led from the bobbin to a place that almost coincides with the extension of the axis of the bobbin.

"To unreel yarn from a bobbin" means, in this patent application, that the yarn is unwound from the bobbin holder by pulling it from the bobbin in a direction that coincides with, or makes an acute angle with, a direction that is perpendicular to the winding axis of the bobbin. The yam then exerts a force on the bobbin surface so that the bobbin is caused to rotate. The yam windings are accordingly unreeled from the bobbin. Once again, the direction of pulling is preferably determined by a yarn guide element, wherein the yarn extends almost in a straight line from the bobbin to the yam guide element.

In an arrangement where the yam is unreeled from the bobbins (a form of yarn take off from a bobbin that is indicated by the technical term "deroule"), the bobbins rotate during yarn take-off. The fact that the bobbins can be moved to a location where they do not need to rotate but may remain stationary during further yarn take-off (a form of yarn take-off from a bobbin that is indicated by the technical term "defile" or“overend unwinding”), makes this method easier to implement.

In a much preferred method according to the present invention, the yarn storage device is provided in order to hold the bobbins, at their respective primary locations and at their respective secondary locations, in a position wherein their bobbin axes extend in the same direction, and this comprises at least one yam guiding device for leading the yarn from a bobbin at a secondary location in a direction wherein it is unwound from this bobbin in an approximately axial direction by a tensile force in the yam during yarn take-off and for leading the yam from a bobbin at a primary location in a direction wherein it is unreeled from this bobbin by a tensile force in the yarn during yam take off.

Preferably, for each set of a primary location and an associated secondary location, a yarn guiding device is provided that comprises at least one yam guide, and this yarn guiding device is provided in order to lead the yam from the bobbin at the secondary location in such a way that it is unwound from this bobbin in an approximately axial direction by a tensile force in the yam during yam take-off, and not to lead the yarn from the bobbin at the primary location so that it is unreeled from this bobbin by a tensile force in the yarn during yam take-off.

In an especially preferred method, each yam guiding device comprises, for each set of a primary and a secondary location, at least one associated yam guiding device, each yarn guiding device comprises a yam eye, and the yam guiding device is provided in such a way that, when replenishing a yam supply, the yam runs along a first yarn path from the moved bobbin at a secondary location through the yam eye of the associated yarn guiding device and is thus unwound from this moved bobbin in an approximately axial direction, and the yarn guiding device comprises a yam clamp for restraining the yarn, after all yarn has been taken from the moved bobbin, whereas it runs along a second yarn path from the new bobbin towards the associated yarn guiding device, and each yarn guiding device is also provided in such a way that, during further uptake of yarn, the yarn running along the second yam path is pulled out of the yarn eye and out of the yarn clamp and then follows a third yam path wherein the yarn is unreeled further from said new bobbin.

The yarn storage device is then preferably provided in order to hold the bobbins at their respective primary location in a position wherein their bobbin axes extend in a first direction, and to hold a bobbin at at least one secondary location in a position wherein said bobbin axis extends in a second direction that is different from the first direction. The first direction and the second direction are preferably not parallel to each other. In a particular method the first and the second direction are approximately perpendicular to one another.

In an alternative method, the yam storage device is preferably provided so that the yarn taken up by the machine from each bobbin placed at a primary location and from each bobbin placed at a secondary location is unwound in an approximately axial direction from the bobbin. With a yarn storage device of this kind, yam is unwound both at the primary locations and at the secondary locations axially from the bobbin ("overend unwinding").

In another preferred method, a respective secondary location is provided for each bobbin in the yarn storage device. As a result, a secondary location is available for each bobbin at any moment, so that each bobbin in the yam storage device can be moved to a secondary location at any moment.

A yarn storage device may also be provided in which the number of secondary locations is less than the number of primary locations. This of course allows the yam storage device to be of more compact design. However, a bobbin may then only be moved when there is at least one secondary location that is not already occupied by another bobbin.

In a most preferred method, a yam storage device is provided in which the vacant bobbin space at each secondary location of the yam storage device is smaller than the vacant bobbin space at each primary location. This is made possible because the vacant bobbin space at the secondary locations must be sufficient for the placement of non full bobbins. A yarn storage device of this kind may be of especially compact design while guaranteeing continuity of production without yam loss. The vacant bobbin space at the secondary locations is then for example at most 75% or more preferably at most 50%, or even more preferably at most 35% of the vacant bobbin space at the primary locations.

In a particular method, a yarn storage device is provided that comprises at least two secondary locations, and at least two yam supplies are replenished simultaneously.

Preferably, the empty bobbin holder is removed from the moved bobbin during this method after the yarn has been taken up on the moved bobbin.

In an especially preferred method, use is made of a yam storage device with a monitoring device, which determines, repeatedly or permanently, a respective bobbin parameter of at least one bobbin that is proportional to the length of the yarn present on the bobbin, and the yarn supply present on a bobbin is replenished when the respective bobbin parameter has reached a predetermined threshold value.

A bobbin parameter is a parameter that is a measure for the size of the yarn supply still remaining on a bobbin. It is for example the bobbin diameter, the yarn layer thickness or the volume that is occupied by the bobbin or the weight of the bobbin. When the length of the yarn on a full bobbin is known approximately, the length of the yarn that has been taken up from said bobbin is also a bobbin parameter from which the size of the remaining yarn supply can be derived. A bobbin parameter may be determined by means of one or more sensors and/or by image analysis by means of an image recording device. The length of yam used may be determined inter alia by leading the yarn over a rotation element that rotates while, and as, the yam moves over it, so that the length of yarn used can be derived from the number of rotations of the rotation element since the start of yarn take-off.

The yarn storage device according to the present invention preferably comprises at least one secondary location where the vacant bobbin space is smaller than the vacant bobbin space at the primary locations. More preferably, the yarn storage device according to the present invention comprises at least one secondary location where the vacant bobbin space is smaller than the average vacant bobbin space of all primary locations of the yarn storage device.

The yarn storage device according to the present invention is preferably provided in order to unreel the yarn taken up by the textile machine from each bobbin placed at a primary location, and to unwind in an approximately axial direction from the bobbin from each bobbin placed at a secondary location. The fact that the bobbins can be moved to a location where they do not need to rotate ("deroule") but may remain stationary during further yarn take-off ("defile") makes replenishment of yarn supplies easier.

In a much preferred embodiment, the yam storage device is provided in order to hold the bobbins, at their respective primary locations and at their respective secondary locations, in a position wherein their bobbin axes extend in the same direction, and comprises a yarn guiding device for leading the yam from a bobbin at a secondary location in a direction wherein it is unwound from this bobbin in an approximately axial direction by a tensile force in the yam during yam take-off, and for leading the yarn from a bobbin at a primary location in a direction wherein it is unreeled from this bobbin by a tensile force in the yam during yam take-off.

Because the bobbins are placed with parallel axes at the primary and secondary locations, moving the bobbins is easy. The structure of the yam storage device is also simpler as a result, wherein the secondary locations are in the free spaces between the primary locations. Twisting of the yam at the level of the joint of the yam of the new bobbin and the yarn of the moved bobbin is avoided by overend unwinding of the yarn on the moved bobbin. The yam guiding device ensures that the transition from yarn take-off from the moved bobbin to yam take-off from the new bobbin proceeds flawlessly.

An especially preferred embodiment is obtained when the yarn guiding device comprises at least one associated yam guide for each set of a primary and a secondary location, and the yarn storage device is provided in such a way that, when replenishing a yarn supply, the yarn runs along a first yam path from a moved bobbin at a secondary location towards the associated yam guide and is thus unwound from this moved bobbin in an approximately axial direction, and, after all yam has been taken from the moved bobbin, runs along a second yam path to an associated yarn guide, and each yarn guide is provided for stopping the guiding of the yam as a consequence of this change of the yarn path, and as a consequence of the stopping of this guiding, the yarn follows a third yarn path wherein the yam is unreeled further from said new bobbin. Moreover, it is preferable to provide the yam storage device in such a way that at their respective primary location the bobbins are held in a position wherein their bobbin axes extend in a first direction, and so that at at least one secondary location a bobbin is held in a position wherein said bobbin axis extends in a second direction that is different from the first direction. The first direction and the second direction are preferably not parallel to each other. In a particular embodiment, the first and the second direction are approximately perpendicular to one another.

The yarn storage device may moreover also be provided so that the yam taken up by the machine from each bobbin placed at a primary location and from each bobbin placed at a secondary location is unwound in an approximately axial direction from the bobbin. With a yarn storage device of this kind the yam is unwound both at the primary locations and at the secondary locations axially from the bobbin ("overend unwinding").

The yarn storage device preferably comprises a first series of primary locations for placing, in a first row next to each other, a number of first bobbins in a position where their axes run transversely to the row direction, and a second series of primary locations for placing, in a parallel second row next to each other, a number of second bobbins in a position where their axes run transversely to the row direction, wherein the first row of bobbins and the second row of bobbins run parallel to each other with a horizontal clearance so that a gap is formed, wherein the yarn storage device comprises a series of secondary locations located in said gap for the placement of non full first bobbins and non-full second bobbins in a position wherein their axes run transversely to said row direction, and wherein the secondary locations are provided in such a way that the non-full bobbins placed thereon form an intermediate row extending in the row direction, in which the successive non-full bobbins are located one after another in the row direction.

The successive non-full bobbins of the intermediate row may be located alternately mainly to the left and mainly to the right of the vertical plane of symmetry of the gap, and be provided alternately as secondary location for a first bobbin and as secondary location for a second bobbin.

A respective secondary location is preferably provided for each bobbin in the yarn storage device.

The number of secondary locations in the yam storage device may also be smaller than the number of primary locations.

In a much preferred embodiment of the yam storage device according to the present invention, the vacant bobbin space at each secondary location of the yarn storage device is smaller than the vacant bobbin space at the primary locations, preferably at most 75%, more preferably at most 50%, even more preferably at most 35% of the vacant bobbin space at the primary locations. If not all primary locations have the same vacant bobbin space, the expression "the vacant bobbin space at the primary locations" may be interpreted as "the average vacant bobbin space of the primary locations of the yarn storage device".

In the most preferred embodiment, the yam storage device is a bobbin creel and the machine is a weaving machine or a tufting machine or a knitting machine. The yarn storage device according to the present invention may be provided with a device with which at least a number of the yams which ran to the textile machine interact with a yarn tensioning device. The yam tensioning device may be provided for controlling the yarn tension of each yam individually and is for example a yarn tensioning system according to patent WO 2017/077454 A9, which comprises a rotatable brake roller, round which one or more yarns are passed at least partially to keep them under tension, and comprises a motor for supplying a torque to the brake roller, wherein this motor is actuable in generator operation to keep the yarn under tension. By allowing a motor to supply a variable torque to the brake roller it may be simpler to respond to deviating and/or varying properties of yarns and/or a path change of the yarn and/or changes in the production process of the textile machine. By actuating the motor in the opposite direction in motor operation, yarn can be recuperated, which may be necessary due to the shedding. A yarn tensioning system of this kind more preferably also comprises measuring means for determining the length of the yarn that has been taken up by the textile machine.

Thus, the length of a yarn kept under tension by this brake roller can be calculated, per brake roller, from the number of revolutions of the brake roller or the angular displacement of the motor and the diameter of the brake roller, without the need for supplementary length measuring sensors. When the length of the yarn is calculated in this way, said measuring means comprise the necessary calculating means for this.

This measurement and/or calculation of the used yam or of the yarn still present in a yarn supply may be used for controlling means for generating a warning signal that indicates that a yarn supply must be replenished, or to generate a control signal that controls one or more means that automatically execute one or more steps of the method according to the present invention and for example form part of the aforementioned monitoring device.

The invention is now explained in more detail on the basis of the following more detailed description of a possible embodiment of a yam storage device according to the present invention and of a possible method for replenishing the yarn supplies in a yarn storage device of this kind. Moreover, it is emphasized that the device and method described are only examples of the general principle of the invention and so should not be regarded in any way as a limitation of the scope of protection, nor of the field of application of the invention.

In this detailed description, reference numbers refer to the appended figures, of which Fig. la is a schematic side view of a bobbin creel with bobbins placed at primary and secondary locations according to the present invention and a weaving machine that is supplied from this bobbin creel; Fig. lb is a front view of a portion of the bobbin creel in Fig. 1, without any bobbins placed thereon; Fig. lc is the front view of Fig. lb, in which the primary and secondary locations are indicated; Fig. 2 is a schematic side view of a portion of a bobbin creel according to the present invention with bobbins placed at primary and secondary locations; Fig. 3 is a perspective view of the portion of the bobbin creel that is shown in Fig.

2; Figs. 4a to 4e each show a perspective view of the portion of the bobbin creel shown in Figs. 2 and 3, wherein the successive drawings show five successive situations during replenishment, according to the present invention, of the yarn supply of the bobbin at top left; and Fig. 5 shows a schematic perspective view of a portion of a bobbin creel with two horizontal rows of 8 primary locations in each case, at which full bobbins are placed and, to the right of these rows, four secondary locations at which non-full bobbins are placed. Fig. 6 shows a schematic perspective view of a portion of a bobbin creel with two horizontal rows of 8 primary locations in each case, at which full bobbins are placed, and two intermediate rows of 8 secondary locations in each case, at which non-full bobbins are placed;

Fig. 7 is a perspective view of a portion of the bobbin creel in Fig. 6 with four full bobbins at respective primary locations and four non-full bobbins at respective secondary locations;

Figs. 8a to 8h are perspective views of the portion of the bobbin creel shown in Fig. 7, wherein the successive figures show the different steps in replenishing a yarn supply;

Fig. 9 shows a schematic perspective view of a portion of a different design of bobbin creel in which, at different levels, parallel horizontal rows of primary locations are provided and wherein, in a gap between these rows of primary locations, a series of secondary locations is provided, and wherein the bobbins at the primary locations and the bobbins at the secondary locations have parallel axes;

Fig. 10 is a top view of the bobbin creel shown in Fig. 9;

Figs. 11a to l id are perspective views of the bobbin creel shown in Figs. 9 and 10, wherein the successive figures show the different steps in replenishing a yarn supply.

The double-face weaving machine (101) shown in Fig. la is equipped for the simultaneous production of two pile fabrics. This weaving machine comprises two warp beams (102), (103) on which the ground warp yams (104), (105) for forming the two ground fabrics are provided and ran to the weaving machine (101). Formation of the pile on these pile fabrics requires a large number of differently coloured pile-warp yarns (21). For each of these different pile-warp yarns (21), a yam supply in the form of a bobbin (1),(2),(3),(4) that is wound on a bobbin holder is provided in a bobbin creel (100). The required yarns (21) ran from these bobbins via guiding means to the weaving machine (101), where they are positioned by means of a jacquard device (106) relative to the levels at which weft yarns are inserted by means of rapiers (not shown). For clarity of the drawing, only a limited quantity of the many bobbins (1),(2),(3),(4) in the bobbin creel (100) are shown, and only a limited number of pile-warp yarns (21) running to the weaving machine are shown.

Figs lb and lc show a portion of the bobbin creel (100) in Fig. la, without the bobbins. The bobbin creel (100) comprises a support structure, which is assembled from a number of vertical support profiles (30). Rotatable bobbin carriers (33) are mounted on these support profiles (30). Each bobbin carrier (33) is provided for carrying a bobbin (l)-(4), (1N)-(4N) in a position of use, wherein it functions as a yarn supply for the weaving machine (101) and wherein the yam can be unreeled from the bobbin while the bobbin rotates about its axis. Each bobbin carrier (33) thus forms a primary location (P1)-(P4) or a secondary location (S1)-(S4) for a bobbin (see Figs lb and lc).

Round each bobbin carrier (33), a space is available, which may be occupied by a bobbin, the so-called "vacant bobbin space". In Fig. lc, this vacant bobbin space is indicated for the primary (P1)-(P4) and for the secondary locations (S1)-(S4) by means of a shaded circle. At these locations (P1)-(P4), (S1)-(S4), the size of the vacant bobbin space may be indicated by means of the diameter (D), (d) of the largest possible bobbin that may be placed at this location in a usage configuration as a yarn supply. The size of the vacant bobbin space at the primary locations (P1)-(P4) is determined by a diameter (D), which is much greater than the diameter (d) that determines the size of the vacant bobbin space at the secondary locations (S1)-(S4). The ratio of on the one hand the size of the vacant bobbin space at the secondary locations (S1)-(S4) and on the other hand the size of the vacant bobbin space at the primary locations (P1)-(P4) is thus the ratio d/D of said diameters, and in the embodiment shown in Figs la, lb and lc is about 40%. In the bobbin creel (100), the bobbin carriers (33) and the associated yarn guiding means (31) are provided both at the primary locations (P1)-(P4) and at the secondary locations (S1)-(S4) in such a way that the yam can be unwound from the bobbins (1)- (4) and can be led via the yarn guiding means (31) to the weaving machine (101). At the primary locations (P1)-(P4), the vacant bobbin space is such that full bobbins (1)- (4) with a standard bobbin diameter (D) can be placed there. A number of much-used standard bobbin diameters are situated between 20 cm and 25 cm, for example 20 cm, 22 cm or 24 cm. In exceptional cases the bobbin diameter may be greater, and may be between 25 cm and 32 cm.

At the secondary locations (P1)-(P4) there is insufficient space for the placement of full bobbins (l)-(4) with a standard bobbin diameter (D), but non-full bobbins may be placed there, provided that their outside diameter (d) is at most 40% of the standard bobbin diameter (D).

In the bobbin creel (100) shown in Figs la and lb, for each primary location (Pl)- (P4), an associated secondary location (S1)-(S4) is also provided. In the bobbin creel in Fig. la, non-full bobbins (1),(2),(3),(4) are placed at all secondary locations (Sl)- (S4). Because more than half of the yam volume has already been taken up by the weaving machine (101) from these bobbins, these bobbins have an outside diameter (d) that is at most 40% of the standard diameter of the full bobbins. At each associated primary location (P1)-(P4), a full bobbin (1N),(2N),(3N),(4N) has been placed, with a new supply of the relevant yam. These full bobbins have a bobbin diameter that is almost identical to the standard diameter (D). The non-full bobbins (1),(2),(3),(4) and the full bobbins (1N),(2N),(3N),(4N) are mounted in such a way that their axes extend parallel to each other and approximately perpendicularly to the plane of the bobbin creel (100). Preferably, however, the bobbin axes are inclined slightly upwards in the direction of the free end of the bobbin. The bobbins are then retained better on their carrier bars under the effect of gravity. An alternative embodiment of the bobbin creel (see Figs. 2 and 3) comprises a number of primary locations (P1)-(P4) where respective full bobbins (IN) - (4N) with bobbin axes (A1)-(A4) extending in a first direction (Rl) on first carrier bars (not visible in the figures) may be placed, wherein their bobbin axes (A1)-(A4) extend horizontally and parallel to each other in a first direction (Rl) that is perpendicular to the plane (V) that is determined by the support structure (30) of the bobbin creel (100).

The bobbin creel (100) comprises, for each primary location (P1)-(P4), a secondary location (S1)-(S4) where respective non-full bobbins (l)-(4) with bobbin axes (Bl)- (B4) extending in a second direction (R2) may be placed on second carrier bars (not visible in the figures), wherein their bobbin axes (B1)-(B4) extend in a second direction (R2) that makes, in a horizontal plane, an acute angle (a) with the plane (V) that is determined by the support structure (30) of the bobbin creel (100). Each secondary location (S1)-(S4) is positioned slanting above the associated primary location (P1)-(P4).

The first carrier bars and the second carrier bars are fastened to the support structure (30) and extend approximately perpendicularly with respect to said plane (V).

The bobbins (1N)-(4N), (l)-(4) each comprise a yam supply in the form of several layers of yarn windings adjacent to each other in the longitudinal direction, which are wound on respective hollow cylindrical bobbin tubes (H1-H4), (H1N-H4N) with a common winding axis that coincides with the bobbin axis. Together, the yarn windings form a yarn volume (40) with an essentially cylindrical external shape with an outside diameter (D),(d) that decreases as more yam is drawn off or unwound from the bobbin.

From each bobbin (l)-(4), (1N-4N), the yam is led to the weaving machine (101), wherein each yarn passes through a respective tube (31), also called "tubing", which is fastened to the support structure (30). The yarns running to the weaving machine (101) are not shown in Figs. 2 and 3. Yam is taken from the bobbins as the production process of the weaving machine progresses and as a function of the weaving pattern.

In the case of the bobbins (1N)-(4N) that are placed at the primary locations (P1)-(P4) with their bobbin axes (A1)-(A4) in the first direction (Rl), the yarn is unreeled tangentially. Owing to the force with which the yam is pulled in the direction of the weaving machine (101), these bobbins are rotated about their bobbin axis. This kind of take-off of yarn from a bobbin is also indicated by the technical term "deroule". The bobbins (l)-(4) that are placed at the secondary locations (S1)-(S4) with their bobbin axes (B1)-(B4) in the second direction (R2) are oriented in such a way that the yarn is drawn off in an approximately axial direction over the end of the bobbin (or over the top of the bobbin) and is thus unwound from the bobbin without the bobbin rotating. This kind of take-off of yam from a bobbin is also indicated by the technical term“defile” or "overend unwinding".

Figs. 4a to 4e in each case show the part of the bobbin creel (100) illustrated in Fig. 3, in successive situations during replenishing of a yam supply according to a preferred method according to the present invention.

According to this method, when a yam supply provided on a bobbin has reached a minimum threshold wherein the bobbin diameter (d) is only 40% of the standard initial diameter (D) of a full bobbin, it is established that this yam supply may be replenished. This can be established visually by an operator. However, a monitoring device (not shown in the figures) may also be provided, interacting with an image recording means (e.g. a camera) and/or one or more sensors that monitor the bobbin diameters of the different bobbins, wherein said monitoring device is programmed to generate a warning signal on reaching the minimum threshold of a bobbin diameter, which indicates that the respective yam supply may be replenished, and/or to generate a control signal, with which the components mentioned hereunder of an automatic replenishing device are controlled to replenish the respective yarn supply automatically.

The bobbin (1) which, in Fig. 4a, top left, is located at a primary location (PI), comprises a yarn supply from which the yam (41) is led via a guide tube (31) to the weaving machine (101). This bobbin has a bobbin diameter (d) that is only 40% of the initial diameter (D) and is thus in the situation defined above wherein the minimum threshold has been reached, so that it is established - by an operator and/or a monitoring device - that this yam supply may be replenished. As a consequence of this finding, in a next step of the method, the respective bobbin (1) whose yarn supply (41) may be replenished is moved to the holding means (not shown in the figure) of the secondary location (SI) that is associated with the primary location (PI) from which the bobbin (1) has come. The situation wherein the bobbin has been moved is shown in Fig. 4b. The yam drawn from this bobbin (1) continues to be led via the guide tube (31) to the weaving machine (101). Now, however, the yarn (41) is no longer unreeled from the bobbin (1), but is unwound over the end of the bobbin without the bobbin (1) rotating.

In another method with a different design of bobbin creel, this movement of the bobbin (1) may also be effected automatically by means of displacing means. Thus, for example each bobbin is carried by a carrier that is movable by a drive motor on a guide rail, to move the bobbin from the aforementioned position at a primary location to the aforementioned position at a secondary location, wherein the drive motor is provided for moving the carrier automatically to the secondary location (SI) after being actuated by a control signal generated by said monitoring device.

As soon as the bobbin (1) has been moved, a new full bobbin (IN) with a new yarn supply of the relevant type of yam is placed at the now vacant primary location (PI). The end (41b) of the yarn (41) on the moved bobbin (1) is then also joined to the unwinding end (51a) of the yam (51) on the new bobbin (IN). The joined yarn ends (41b), (5 la) and the join itself are shown enlarged and schematically in Figs. 4c and 4d.

The situation after placement of the full bobbin (IN) and after joining the yarns (41), (51) is shown in Fig. 4c. Because both the new bobbin (IN) and the moved bobbin (1) are stationary, joining of the yams is easy to carry out, and it means that further yarn take-off from the moved bobbin (1) does not cause twisting in the yarn located between the two bobbins (1),(1N).

During the weaving process, the weaving machine takes further yarn (41) from the moved bobbin (1) and continues to do so until all yam (41) has been removed from this bobbin (1). Therefore there is not the slightest yam loss. Because the end (41b) of the yarn on the moved bobbin (1) is joined to the unwinding end of the yarn (51) on the new bobbin (IN), the yarn from the new bobbin (IN) is pulled along automatically in the direction of the weaving machine and the yam (51) continues to be unreeled automatically from the new bobbin (IN). This yam take-off now once again takes place tangentially through rotation of the bobbin (IN). The yam (51) drawn from this bobbin (IN) continues to be led via guide tube (31) to the weaving machine (101). Fig. 4d shows the situation at the moment when the last yam is unwound from the moved bobbin (1) and the yarn (51) from the new bobbin is pulled along by the yarn joint (41b, 51a).

In the aforementioned other method with a different design of bobbin creel, placement of a new bobbin (IN) at the now vacant primary location (PI) and joining of the yarn ends (41b, 5 la) can be effected automatically by means of placing means and joining means of an automatic replenishing device. The placing means then comprise for example means for moving a full bobbin from a bobbin supply to the bobbin creel and for placing it in the correct position at the now vacant primary location. For this purpose, these placing means may for example, like the displacing means described above, comprise a carrier that is movable by a drive motor on a guide rail in order to move the bobbin from the bobbin supply to the now vacant primary location, wherein the drive motor is provided for moving the carrier automatically to the primary location after actuation by a control signal, for example after it is established by image detection and/or a sensor that the primary location is free.

Joining of the yarn ends (41b), (51a) may also be accomplished automatically by means of known joining means for the automatic joining of yarns. These joining means may also form part of a replenishing device.

As the last step of the method, the empty tube (HI) of the moved bobbin (1) is then removed, to free up this secondary location (SI) for the next replenishment of the relevant yarn. It is obvious that removal of this empty tube (HI) can also be automated, for example by means of controllable pushing means, which form part of the aforementioned replenishing device. Fig. 5 shows a portion of another embodiment of a bobbin creel (100). The bobbin creel (100) once again comprises a support structure assembled from vertical support profiles (30) and bobbin carriers (not visible) fastened thereon, for placing bobbins (1N)-(8N) in horizontal rows above one another at primary locations, wherein they are oriented with their bobbin axes (A1)-(A8) horizontal and parallel to each other and perpendicular to the plane (V) of the bobbin creel (100). The yarns are led from the bobbins via respective guide tubes (31) to the weaving machine (101).

However, this bobbin creel (100) does not have a secondary location for each primary location. For each horizontal row of eight primary locations, at the right edge of this row, only two secondary locations are provided. At these two secondary locations per row, the respective bobbins (1), (8) are mounted in such a way that their bobbin axes (B1),(B8) are located in parallel vertical planes and from the bottom end to the top end they slant to the left. The vacant bobbin space at the secondary locations is in this case 50% of the vacant bobbin space at the primary locations. The bobbin diameter (d) of the bobbins at the secondary locations may thus be at most 50% of the bobbin diameter (D) of the largest possible full bobbins (1N)-(8N) that may be placed at the primary locations.

With a bobbin creel of this kind (100), per horizontal row of eight bobbins, only two bobbins may thus be moved to a secondary location at the same time, so that per row of bobbins, only two yarn supplies may be replenished at the same time according to the method according to the present invention. The yam supplies of the bobbins of the same row may thus be replenished in successive turns of at most two yarn supplies at a time.

Because the vacant bobbin spaces at the secondary locations may be much smaller than the vacant bobbin spaces at the primary locations, a bobbin creel of this kind with a limited number of secondary locations must be somewhat larger than a bobbin creel that only has primary locations, whereas the presence of the secondary locations offers the advantage that replenishment of yam supplies can be more planned, without yarn loss and without any interruption of the production process of the textile machine. In an alternative embodiment, the bobbin creel (100) comprises a plurality of horizontal rows of primary locations, in each case with an intermediate horizontal row of secondary locations between every two rows. On the portion of the bobbin creel shown in Fig. 6, we see a part of two horizontal rows each with 8 primary locations and a part of two intermediate horizontal rows each with 8 secondary locations. A respective full bobbin (1N)-(8N) is placed at each primary location, and a bobbin (1)- (8) that still only contains a small amount of yam is placed at each secondary location. The diameter (d) of these non-full bobbins (l)-(8) is for example about 35% of the diameter (D) of the full bobbins (1N)-(8N).

The bobbin creel (100) comprises a support structure that is assembled from vertical support profiles (30). The bobbins (l)-(8), (1N)-(8N) are supported on carrier bars (not visible in the figures) that are fastened to these support profiles (30) and extend from these support profiles approximately perpendicularly to the plane (V) of the bobbin creel (100) but inclined slightly upwards, in the direction of their free end. Each primary location with a full bobbin (1N)-(8N) has an associated secondary location for a non-full bobbin, wherein the unwinding end (front end) of the yarn on the full bobbin (1N)-(8N) is joined to the rear end of the yam that is still present on the non-full bobbin 0)-(8).

Furthermore, for each pair of a primary location and an associated secondary location, a guiding device (42) is also provided, which comprises a yam eye (43) and a yarn clamp (44). Its function is explained by the description of the successive situations during replenishment of a yarn supply of this bobbin creel, referring to Figs. 8a to 8h.

Fig. 7 shows a smaller portion of the bobbin creel (100) in Fig. 6, with four full bobbins (1N)-(4N) and four non-full bobbins (l)-(4).

Fig. 8a shows a situation wherein the yam supply of the bobbin (1) at the primary location top left must be replenished because the remaining amount of yarn has reached a certain minimum threshold. For this purpose, in a first step this bobbin is moved to the associated secondary location top left (see Fig. 8b) so that the yarn continues to be unwound from the moved bobbin (1). The yam is led from the moved bobbin (1) via the yarn eye (43) so that the yam is withdrawn over the end of the bobbin and is unwound from the bobbin (1) in an approximately axial direction (overend unwinding).

In a next step, a new full bobbin (IN) is placed at the now vacant primary location (PI) (see Fig. 8c).

In a third step, the front unwinding end of the yam on the full bobbin (IN) is joined to the rear end of the yarn on the moved non-full bobbin (1) wherein the portion of yarn extending between the two bobbins (1),(1N) is gripped by said yarn clamp (44) (see Fig. 8d). When all yarn has been withdrawn from the moved bobbin (1) (see Fig. 8e), the yarn is first pulled out of the yam eye (43) (see Fig. 8f) and then also out of the yarn clamp (44) (see Fig. 8g). Then the yam is unreeled further from the new bobbin (IN) (with the bobbin rotating) (see Fig. 8g). Finally, the empty tube (HI) of the moved bobbin (1) is removed (see Fig. 8h).

In yet another embodiment of the bobbin creel (see Fig. 9), the bobbin creel (100) comprises, at different levels, parallel horizontal rows of primary locations, wherein a series of secondary locations is provided in a gap between these rows of primary locations.

On the portion of the bobbin creel shown in Figs. 9 and 10, only two such levels are shown, and in each case two successive full bobbins (1N),(2N) of a left row of primary locations and two successive bobbins (3N),(4N) of a right row of primary locations are shown per level. The axes of these bobbins are approximately perpendicular to the direction (R) of the rows (called the row direction).

At each level, a series of secondary locations is provided between the left row and this right row of primary locations. In Figs. 9 and 10, at four successive secondary locations, respective non-full bobbins (3),(1),(4),(2) are placed, which are located one after another in the row direction (R). The bobbin axes of the non-full bobbins (l)-(4) in this gap also extend in a direction that is approximately perpendicular to said row direction (R). The successive non-full bobbins (3),(1),(4),(2) of the intermediate row are positioned alternately mainly to the left and mainly to the right of the vertical plane of symmetry (S) of the gap, and are placed at secondary locations which alternately belong to a primary location of the left row and belong to a primary location of the right row of primary locations. As can be seen most clearly in Fig. 10, the secondary locations to the right of the plane of symmetry (S), on which the first (3) and the third non-full bobbin (4) are placed, belong respectively to the primary locations of the right row on which the full bobbins (3) and (4) are placed, and the secondary locations to the left of the plane of symmetry (S) on which the second (1) and the fourth non-full bobbin (2) are placed belong respectively to the primary locations of the left row on which the full bobbins (1) and (2) are placed.

Figs. 1 la to l id show the successive steps of the method during replenishment of the bobbin creel, a portion of which is shown in Figs. 9 and 10. The two bobbins that are placed at a primary location and at an associated secondary location have their bobbin axes extending one after another and may be moved together on a slidable carrier (60) in the longitudinal direction of their bobbin axes.

If the amount of yarn on a bobbin (3) has reached a certain minimum threshold, the carrier is moved back, as shown in Fig. 1 lb, the non-full bobbin (3) is placed at the secondary location (i.e. the front part of the carrier (60)), after which a new full bobbin (3N) is placed at the now vacant primary location (i.e. the rear part of the carrier (60)). This situation is shown in Fig. 11c. The yam ends of the yam on the non-full bobbin (3) and of the yarn on the full bobbin (3N) are joined together. The carrier (60) is finally pushed forward again so that the bobbins return to their original place in the bobbin creel (100). During these operations, yam take-off continues, wherein the yarn is led through the front end of the carrier (60) in the shape of an inverted U.

Claims

1. Method for replenishing yam supplies in a yam storage device (100) in which several yarn supplies in the form of bobbins (1-16) wound on respective bobbin holders (HI -HI 6) are placed at respective primary locations (PI -PI 6), while yarns (21) are withdrawn from these supplies by a machine (101) for the patterned production of textile products, wherein replenishment of a yarn supply involves providing a new bobbin (1N-16N) with a new yarn supply at a primary location (PI -PI 6) in the yam storage device (100), characterized in that a yarn supply is replenished by

moving a non-full bobbin (1-16) that contains the yarn supply to be replenished, from its primary location (PI -PI 6) to a secondary location (SI -SI 6) in the yam storage device (100), so that the yarn (21) can continue to be withdrawn from this moved bobbin (1-16) by the machine (101) in operation,

placing the new bobbin (1N-16N) at the now vacant primary location (PI), and

joining an unwinding end (la) of the yam present on the new bobbin (1N- 16N) to an end (lb) of the yam present on the moved bobbin (1-16), so that, after the yarn on the moved bobbin (Bi) has been taken up, the yarn continues to be taken up from the new bobbin (1N-16N).

2. Method for replenishing yam supplies according to Claim 1, characterized in that the yarn storage device (100) is provided in such a way that the yarn (21) taken up by the textile machine (101) is unreeled from a bobbin (1-16, 1N-16N) placed at a primary location (P1-P16), and it is unwound from a bobbin (1-16) placed at a secondary location (S1-S6) in an approximately axial direction (R2) of the bobbin.

3. Method for replenishing yam supplies according to Claim 2, characterized in that the yarn storage device (100) is provided for holding the bobbins at their respective primary locations (P1)-(P4) and at their respective secondary locations (S1)-(S4) in a position wherein their bobbin axes extend in the same direction, and comprises at least one yam guiding device (42) for leading the yarn from a bobbin (1) at a secondary location in a direction wherein owing to a tensile force in the yarn during yam take-off it is unwound in an approximately axial direction from this bobbin (1), and for leading the yarn from a bobbin (IN) at a primary location in a direction wherein, owing to a tensile force in the yarn during yarn take-off, it is unreeled from this bobbin (IN).

4. Method for replenishing yam supplies according to Claim 3, characterized in that the yarn guiding device (42) comprises for each set of a primary and a secondary location at least one associated yam guide (43), (44), and in that the yarn storage device is provided in such a way that, when replenishing a yarn supply, the yarn runs along a first yam path from a moved bobbin (1) at a secondary location towards an associated yam guide (43) and is thus unwound in an approximately axial direction from this moved bobbin (1), and, after all yarn has been taken from the moved bobbin (1), runs along a second yarn path towards the associated yam guide (43), in that each yarn guide (43), (44) is provided for stopping the guiding of the yam as a consequence of this change of the yarn path, and in that the yam as a consequence of the stopping of this guiding, follows a third yam path wherein the yam continues to be unreeled from said new bobbin (IN) at the primary location.

5. Method for replenishing yam supplies according to Claim 2, characterized in that the yarn storage device (100) is provided for holding the bobbins at their respective primary location (P1)-(P4) in a position wherein their bobbin axes extend in a first direction, and for holding a bobbin at at least one secondary location in a position wherein said bobbin axis extends in a second direction that is different from the first direction.

6. Method for replenishing yam supplies according to Claim 5, characterized in that the first direction and the second direction are not parallel to each other.

7. Method for replenishing yam supplies according to Claim 1, characterized in that the yarn storage device (100) is provided for unwinding the yarn taken up by the machine (101) from each bobbin placed at a primary location and from each bobbin placed at a secondary location in an approximately axial direction from the bobbin.

8. Method for replenishing yam supplies according to one of the preceding claims, characterized in that a respective secondary location is provided for each bobbin in the yarn storage device (100).

9. Method for replenishing yam supplies according to one of Claims 1 to 7, characterized in that the number of secondary locations in the yam storage device (100) is less than the number of primary locations.

10 Method for replenishing yam supplies according to one of the preceding claims, characterized in that the vacant bobbin space at each secondary location of the yarn storage device (100) is smaller than the vacant bobbin space at each primary location.

11. Method for replenishing yam supplies according to Claim 8, characterized in that the vacant bobbin space at the secondary locations is at most 75%, preferably is at most 50%, more preferably is at most 35% of the vacant bobbin space at the primary locations.

12 Method for replenishing yam supplies according to one of the preceding claims, characterized in that the yam storage device (100) comprises at least two secondary locations and in that at least two yam supplies are replenished simultaneously.

13. Method for replenishing yam supplies according to one of the preceding claims, characterized in that, after the yam on the moved bobbin has been taken up, the empty bobbin holder of the moved bobbin is removed.

14. Method for replenishing yam supplies according to one of the preceding claims, characterized in that the yam storage device comprises a monitoring device that determines, repeatedly or permanently, a respective bobbin parameter of at least one bobbin that is proportional to the length of the yam present on the bobbin, and in that the yarn supply present on a bobbin is replenished when the respective bobbin parameter has reached a predetermined threshold value.

15. Yarn storage device (100) for a machine (101) for the patterned production of textile products, in which several yam supplies in the form of bobbins wound on respective bobbin holders (1-16) are placed at respective primary locations (Pi pe), characterized in that the yam storage device (100) comprises

displacing means that are provided for moving a non-full bobbin (Bi) from its primary location (Pi) to a secondary location (Si), so that the yarn (1) can continue to be taken up from this moved bobbin (1-16) by the machine (101) in operation,

placing means that are provided for placing a new bobbin (1N-16N) at the now vacant primary location (PI), and

joining means that are provided for joining an unwinding end (la) of the yarn present on the new bobbin (1N-16N) to an end (lb) of the yarn present on the moved bobbin (1-16), so that, after the yam (1) has been taken up on the moved bobbin (1), the yam continues to be taken up from the new bobbin (1N-16N).

16. Yarn storage device (100) according to Claim 15, characterized in that it comprises at least one secondary location where the vacant bobbin space is smaller than the vacant bobbin space at the primary locations.

17. Yarn storage device (100) according to Claim 15 or 16, characterized in that the yarn storage device (100) is provided for unreeling the yarn (1-6) taken up by the machine (101) from each bobbin placed at a primary location, and for unwinding from each bobbin placed at a secondary location, in an approximately axial direction from the bobbin.

18 Yarn storage device (100) according to one of Claims 15 to 17, characterized in that it is provided for holding the bobbins at their respective primary locations (P1)-(P4) and at their respective secondary locations (S1)-(S4) in a position wherein their bobbin axes extend in the same direction, and in that it comprises a yarn guiding device for leading the yam from a bobbin at a secondary location in a direction wherein it is unwound from this bobbin in an approximately axial direction by a tensile force in the yam during yam take-off, and for leading the yarn from a bobbin at a primary location in a direction wherein it is unreeled from this bobbin by a tensile force in the yam during yam take-off.

19. Yarn storage device (100) according to Claim 18, characterized in that the yarn guiding device for each set of a primary and a secondary location comprises at least one associated yam guiding device (43), (44), in that each yarn guiding device (43), (44) comprises a yam eye (43) and is provided in such a way that, when replenishing a yam supply, the yam runs along a first yarn path from the moved bobbin at a secondary location through the yam eye (43) of the associated yarn guiding device (43), (44) and is thus unwound from this moved bobbin in an approximately axial direction, and in that the yam guiding device comprises a yarn clamp (44) for restraining the yam, after all yam has been taken from the moved bobbin, while it runs along a second yam path from the new bobbin towards the associated yam guiding device (43), (44), and in that each yarn guiding device (43), (44) is also provided in such a way that, during further uptake of yarn, the yarn running along the second yam path is pulled out of the yarn eye (43) and out of the yam clamp (44) and then follows a third yarn path wherein the yarn is unreeled further from said new bobbin.

20. Yarn storage device (100) according to one of Claims 15 to 17, characterized in that the yarn storage device (100) is provided for holding the bobbins at their respective primary location in a position wherein their bobbin axes extend in a first direction, and for holding a bobbin at at least one secondary location in a position wherein said bobbin axis extends in a second direction that is different from the first direction.

21. Yarn storage device (100) according to Claim 20, characterized in that the first direction and the second direction are not parallel to each other.

22 Yarn storage device according to Claim 15 or 16, characterized in that the yarn storage device (100) is provided for unwinding the yam (1-6) taken up by the machine (101) from each bobbin placed at a primary location and from each bobbin placed at a secondary location in an approximately axial direction from the bobbin.

23. Yarn storage device (100) according to Claim 22, characterized in that the yarn storage device comprises a first series of primary locations for placing, on a first row next to each other, a number of first bobbins in a position where their axes ran transversely to the row direction, and a second series of primary locations for placing, in a parallel second row next to each other, a number of second bobbins in a position wherein their axes ran transversely to the row direction, in that the first row of bobbins and the second row of bobbins ran parallel to each other with a horizontal clearance so that a gap is formed, in that the yarn storage device comprises a series of secondary locations located in said gap for the placement of non-full first bobbins and non-full second bobbins in a position wherein their axes ran transversely to said row direction, and in that the secondary locations are provided in such a way that the non-full bobbins placed thereon form an intermediate row extending in the row direction in which the successive non-full bobbins are located one after another in the row direction.

24. Yarn storage device (100) according to Claim 23, characterized in that the successive non-full bobbins of the intermediate row are located alternately mainly to the left and mainly to the right of the vertical plane of symmetry of the gap, and are provided alternately as secondary location for a first bobbin and as secondary location for a second bobbin.

25. Yarn storage device (100) according to one of Claims 15 to 24, characterized in that a respective secondary location is provided for each bobbin in the yam storage device (100).

26. Yarn storage device (100) according to one of Claims 15 to 24, characterized in that the number of secondary locations in the yam storage device (100) is less than the number of primary locations.

27. Yarn storage device (100) according to one of Claims 15 to 26, characterized in that the vacant bobbin space at the secondary locations is smaller than the vacant bobbin space at the primary locations, preferably is at most 75%, more preferably is at most 50%, even more preferably is at most 35% of the vacant bobbin space at the primary locations.