DESCRIPTION Technical field This invention relates to a weave and warp yarn cutting machine particularly recommended for cutting threads arranged both vertically and horizontally in any type of fabric.

Background Art As it is known, in the production of fabrics and in particular with jacquard working, during weaving there are ends of both the horizontal and vertical threads which remain loose and must be cut off and eliminated.

At present, there are machines in existence which cut the loose horizontal threads, which are comprised, synthetically, of a cutting unit with fixed helicoidal blades and a sub-blade which enables the thread cutting to be limited to threads whose length exceeds 3.5 cm, while, at present, nothing exists to cut shorter threads, and this condition is perceived as a serious limitation to the execution of designs.

The situation regarding the vertical threads is quite different. In fact, there is no machine on the market which is able to cut the vertical threads in light fabrics or in fabrics with threads whose length exceeds approximately 10 cm.

There does exist, however, a machine which is able to cut threads in heavy fabrics with extremely short thread lengths.

Users of this machine have encountered notable problems, including therein the need for constant and continuous maintenance as the loose threads tend to catch in the blades.

A further problem with the aforesaid machine is derived from the fact that these blades are subject to notable wear, above all due to their overheating, with the consequent need for frequent replacements. Furthermore, when a blade on this machine no long cuts, the operator is unable to realise this straight away since there is only one blade transmission, and consequently there'is a considerable risk of making holes in the fabric being worked and ruining it.

In addition, at present, there exists a machine for cutting threads in lace which can also be used for certain work with threads with lengths of between 3 and 15 cm. This machine performs the thread cutting by means of small fixed blades that move horizontally. The machine just described, does have, however, a plurality of drawbacks.

A first drawback is derived from the fact that the small fixed blades allow only a somewhat limited productivity as they wear out quickly, so reducing the cutting capacity over time.

A further drawback that emerges is derived from the fact that the small blades, moving horizontally, do not allow thick threads to be cut, only thin ones, so limiting the use possibilities.

A still further drawback encountered is derived from the fact that the loose threads of a certain length cause blockages of the small blades with the consequent iamming of the machine and

interruptions in operation for the purpose of restoring it to an operative condition.

The situation described leads to rather substantial production costs and fairly long production times due to the frequent interruptions required for maintenance involving both the small blades and the machine as a whole.

In addition to the situation outlined above, at present, jacquard fabrics are not produced, for example in the curtains sector, since it is not possible to cut the warp threads,. both those of certain length and those of a certain thickness.

The situation illustrated previously shows how, at present, there exist certain machines which are able to perform vertical cuts but each of these has such serious limitations that the production of jacquard fils coupe fabrics with warp threads, as well as particular designs-that are required by the distance between the threads during weaving-are prevented.

Disclosure of Invention The aim of this invention is substantially to overcome the drawbacks of the commonly known technique, overcoming the aforesaid difficulties by means of a fabric weave and warp yarn cutting machine, able to cut waving vertical and horizontal threads in a fabric.

A second aim of this invention is to realise a fabric weave and warp yarn cutting machine able to cut, once, threads up to approximately 3 cm in length and, twice, threads with greater lengths.

A third aim of this invention is to realise a fabric weave and warp yarn cutting machine able to offer great ease of use with any fabric type and consistency and enable an easy and safe hold on the threads during the cutting phases with any yarn type and length.

A further aim of this invention is to realise a weave and warp yarn cutting machine that can be combined with a shearing machine to create a complete working cycle.

A still further aim of this invention is to have a weave and warp yarn cutting machine that can offer good hourly productivity with adjustable cutting speeds.

A still further aim of this invention aim is to realise a weave and warp yarn cutting machine which is simple to manufacture and operates well.

These and other aims which will better emerge in this description are substantially met by a fabric weave and warp yarn cutting machine as illustrated in the claims that follow.

These and other characteristics and advantages will better emerge in the detailed description that follows of a fabric weave and warp yarn cutting machine according to this invention, with reference to the plates enclosed, supplied purely in the form of an indicative and therefore non-limiting example, in which : - figure 1 shows, schematically, a weave and warp yarn cutting machine according to this invention ; - figure 2 shows, schematically, a variant of the weave and warp yarn cutting machine in question.

With reference to the aforesaid figures, 1 is the fabric weave and warp yarn cutting machine, according to this invention, as a whole.

As shown in figure 1, the yarn cutting machine 1 is substantially composed of a supporting structure 2 designed to support a series of working units and a plurality of rollers 3 that enable the drafting of a fabric 4.

In more detail, the machine 1 comprises, in the input section, a tensioning unit 5, of a substantially known type, consisting of a tension regulator, the so-called dandy roller, which enables the tension of the fabric 4 to be maintained constant up to the cutting point. The tension regulator is a cylinder 5a that is operated and adjusted by means of compressed air pistons calibrated in such a way that the fabric tension is maintained at a suitable level to prevent the presence of dangerous sagging or bumps during the cutting. Furthermore, the tensioning unit 5 comprises a number of rollers 3 envisaged for the fabric handling and an input roller 3a.

After the tensioning unit 5, the machine has an extending unit 6, also of a substantially known type, which allows the extension of the fabric near the cutting point for the purpose of eliminating any creases. The extending unit 6 is composed of a cylinder 6a fitted with a rib spiralling towards the exterior which allows the fabric to be opened and spread.

In addition, the machine 1 comprises a resting element 7 for the fabric 4 substantially composed of a wedge 70, consisting of a steel bar, which is able to move vertically in order to become a suitable rest for the fabric when the loose threads are cut. In more detail, the

movement of the steel bar that constitutes the wedge is managed by handling and control means (not shown in the figure) and by software that allows, by means of motor reducers, the millimetric adjustment of the bar's vertical shifting and the memorisation of the position of the said bar, in order to reset it automatically at any time. Furthermore, there is an aluminium cross member 9 positioned above the wedge which is supported by the supporting structure 2 and an iron beam 10 fitted with ball bearings 11 to allow the oscillation of the cross member 9 from right to left and vice versa.

This linear movement is always controlled by the handling and control means and by the software which, in it its turn, controls an inverter and a motor reducer that make a connecting rod connected to the cross member 9 interact to reach high movement speeds.

According to the current embodiment, the machine 1 comprises a cutting unit 8 essentially consisting of a plurality of rotating circular blades 80 each of which is driven by moving means 81 consisting of a small motor and of a plurality of holding means 82 composed of feet envisaged for lifting the threads and which will be described in detail below. In addition, the blades 80 are placed transversally to the fabric to allow the feet to grip the thread laterally and lift it so that the rotating blades can cut it.

In particular, the cutting unit 8 is positioned on the cross member 9 which is preset to move horizontally driven by a motor not shown in figure 1.

Applied to the cross member 9 are the small motors that drive the blades 80, which, in their turn, work in contact with counterblades

83 envisaged to render the cutting efficient and positioned on the holding means 82.

In particular, the moving means 81 ensure that each of the small motors is protected by its own fuse, to prevent it burning out if the small motor should overstrain. If a small motor should stop, an emergency system would be triggered which would enable the machine's immediate stop to prevent the fabric being damaged. Each small motor is fitted with its own switch with which to activate or deactivate it whenever necessary.

For correct and efficient maintenance, each of the small motors can be removed individually and quickly, and they are all fitted with their own grinding system and a protective element positioned behind the blades for the purpose of protecting the transmission gears connected to the motor from the intrusion of the threads.

In the current embodiment, the feet have a particular conformation which allows them to fit under the threads and can lift them from the fabric 4, so that the blades can then cut them without coming into contact with the fabric and therefore running the risk of damaging it.

Furthermore, the feet, preferably built of a metallic material, are arranged in such a way so as to rest constantly on the blades to always offer the best possible cutting point. This rest is composed of an elastic clamping element which, in the current embodiment, consists of a spring.

Lastly, as mentioned earlier, the cutting unit comprises an automatic blade sharpening device. The device is located near each blade and

is designed to start operating, as controlled by the operator, to grind the blade while the latter is in use.

In agreement with the current embodiment, the cutting unit 8 is fitted with a protective element for the blades built of a transparent material to allow the operator to see the cutting unit and check its blades.

In addition to the above, the machine 1 in question envisages the presence of a suction unit 12 formed of a suction hood located in front of the cutting unit and envisaged to obtain the suction and removal of the threads from the fabric in the cutting zone. In more detail, the suction obtained allows the threads present that already been cut to be tautened so they can be cut again before being definitively sucked away.

Furthermore, the suction unit 12 contributes to the blade cooling.

As shown in figure 1 and in agreement with this invention, the machine 1 has a blowing unit 13 located to the rear of the cutting unit 8 and assigned to carrying out the cleaning of the area and cooling the moving means 81 and the cutting unit as a whole.

In addition to the above, the supporting structure 2 is equipped with a pair of footboards 20a and 20b located, respectively, the first 20a in front of the cutting unit and the second 20b to the rear of the same unit. The footboard 20a is envisaged to allow operator easy access to the cutting unit for the adjustments necessary depending on the type of fabric being worked, while the second footboard 20b is designed for the operator to check the cutting carried out. Both

footboards allow access to the cutting unit for machine checks and maintenance.

The machine 1 in question has an output lapping unit 14 designed to perform the folding of the fabric called lapping.

The lapping unit 14, of a substantially known type, essentially consists of draft rollers 3, a lap roller 14a and a pair of oscillating cylinders 14b and 14c, in between which the fabric 4 passes and is folded as it moves forwards and backwards while moving downwards.

According to the current embodiment and as mentioned earlier, the machine 1 comprises the handling and control means for all the activities, for all the adjustments and for all the components of the machine itself and of their drives with specific software for each procedure and phase of the fabric handling and processing.

Last of all, the machine 1 is fitted with a main electric control panel and a second electric panel specific to the cutting unit. There are warning lights on the second panel that light up (one for each small motor) which are designed to display clearly, which, if any, of the small motors have stopped.

One variant of the machine in question, shown in figure 2, has the resting element 7 composed of a plurality of rollers which create a resting zone under the cutting unit. In more detail, in the embodiment currently illustrated there are four rollers. The first roller 7a and the last roller 7d have a larger diameter than the others and determine the tension and the support while the central rollers

7b and 7c, given the distance between the first and the fourth, are designed to ensure the fabric does not yield in the middle.

In particular, the rollers 7a, 7b, 7c and 7d are adjustable heightwise as they are driven from the top downwards and vice versa by pneumatic jacks which allow it to advance at an almost decimal rate. Furthermore, the movement of rollers 7a, 7b, 7c and 7d is controlled by handling and control means and by specific software and by an encoder that reads their shifting.

Also in this embodiment, the machine 1 comprises a cutting unit 8 essentially consisting of a plurality of rotating circular blades 80 each of which is driven by moving means 81 consisting of a small motor and a plurality of holding means 82 composed of feet envisaged for lifting the threads. In addition, the blades 80 are located in front of the fabric to allow the feet to run into the thread and lift it so that the rotating blades can then cut it. Furthermore, each blade is adjustable heightwise by means of an adjustment slot.

In particular, the cutting unit 8 is positioned on a plurality of cross members 9 which are laid out mutually parallel and are each designed to house a plurality of blades laid out substantially in several rows, which are staggered to allow threads as short as lcm in lengths to be cut.

Also in this case, applied to the cross members 9, are the small motors that control the blades 80, which, in their turn, work in contact with counterblades 83 envisaged to render the cutting efficient and positioned on the holding means 82.

The yarn cutting machine 1 in question is conceived to work from a resting condition, in which it is inactive and there is no roll of fabric placed on the rollers, to an operating condition in which the blades cut the loose threads present in the fabric one or two times.

After this predominantly structural description, there will now follow a description of the operation of the invention in question.

When it is necessary to cut the loose threads resulting from the working of a fabric, for example jacquard, the operator in charge of the machine must insert the fabric, of any length, into the machine.

The fabric 4 is fed by means of rollers 3 operated by the handling and control means via specific software. The rollers are driven by inverter motors that allow the rollers to turn and transport the fabric.

As it moves, the fabric initially meets with the tensioning unit 5 and then immediately afterwards, an input roller 3a, followed, in it is turn, by the tension regulator Sa.

Before reaching the cutting area, the fabric performs a series of passages from the top downwards, indicated schematically in figure 1, through a plurality of idler rollers 3, moving, likewise, under the first footboard 20a where the operator can then adjust and control the cutting unit. The fabric continues to move from the bottom upwards, meeting with the extending unit 6 and, by means of the extending cylinder 6a, is extended and stretched to remove any creases.

Immediately afterwards, the fabric meets the resting element 7 where the wedge 70 determines the resting point for the fabric where the cutting unit 8 will be working.

In particular, the wedge 70 moves from the bottom upwards to position the fabric in the exact point at which the cutting will be carried out.

In fact the fabric, which has loose warp threads, i. e. which has threads that are waving but directed towards the two ends, passes over the wedge so that the waving threads are stretched, then meets the feet, which are moving constantly, along its entire width.

The feet lift the threads to allow the blades to effect the first and only cut if the thread has a length of 1.2 to 3 cm, while, if the thread length is greater, from approximately 4 cm upwards, the blades 80 will effect a second cut.

This second cut is rendered possible by the action of the suction unit 12 which, with the suction hood positioned in front of the blades, sucks in horizontally the end of the thread already cut the first time, tautening it once again to allow the second cut. Without this suction the blades would jam because the cut off thread of such a length would wind and entangle itself around the blade and small motor causing interruptions to the work every few minutes. The suction, furthermore, is designed to cool the heat caused by the friction of the blades with the counterblades, consequently preventing them overheating and becoming red-hot. In this way, the blade wear is reduced considerably and likewise consequently their maintenance, but above all their frequent replacement, which unfortunately occurs

in machines applying the commonly known technique, is also reduced.

In addition, to further reduce the friction between the blade and counterblade and keep the components of the cutting unit clean and therefore the cutting efficient, there is a hood applied behind the cross member 9 through which the air produced by a blower 13 passes. The hood always moves contemporaneously with the cross member and the air blows directly onto the point of resistance between the between the foot and the blade.

Once it has passed the wedge and therefore the cutting area, the fabric performs a passage from the top downwards where there is a further draft roller 3b which feeds it under the second footboard, above which the operator is performing the cutting check. Next, the fabric moves up again, drawn by the lapping roller 14a, which folds it over.

Similarly, in the second embodiment, the fabric 4 runs the same route until it reaches the resting element 7 in which the cylinders 7a, 7b, 7c and 7d support the fabric. At this point, the fabric that has waving threads laid out horizontally to be cut meets the feet that lift the threads that will then be cut by the blades which are laid out in rows positioned one after the other with the first slightly staggered in relation to the second and so forth. In this way, it is possible to cut the very short waving threads. Once the cutting of the threads is complete, the fabric continues through the same phases illustrated previously.

In this way, this invention fulfils the proposed aims.

In fact, the yarn cutting machine in question is able to cut all types of vertical and horizontal threads in a fabric, from those which are only a few millimetres long to those with lengths of several centimetres.

The machine spares the operator, completely, from performing endless maintenance to fix and/or replace the cutting elements, as happens with the currently known techniques. Furthermore, when replacements are necessary, operations are much quicker as the individual small motor or blade is replaced, not the entire unit, therefore the interruptions in the machine's operation are extremely limited in terms of both frequency and duration.

Advantageously, the presence of the suction unit renders it possible to cut loose threads with lengths of over 15 cm without jamming the cutting unit.

A further advantage emerges from the fact that the machine is also able to cut thick yarns that until now were impossible to cut.

Furthermore, with the machine according to this invention is possible to effect a clean cut of the thread without it fraying or being pulled, as sometimes happens with the commonly known technique.

In addition to the above, the machine according to this invention, offers the possibility of being connected to a shearing machine without interrupting the operations by fitting a roll of fabric once only for both the cutting and shearing operations, so curbing the working times.

Furthermore, the machine makes it possible to have complete and precise control over the operating passages and all the components.

A still further advantage of this invention is that it offers a machine that is remarkably easy to use, simple to manufacture and operates well.

Naturally, numerous modifications and variants can be applied to this invention, all of which remain within the field of invention which characterises it.