WO2020094497A1

WO2020094497A1 - Device and method for feeding a thread

Info

Publication number: WO2020094497A1
Application number: PCT/EP2019/079825
Authority: WO
Inventors: Thomas Mutschler; Marcus Weber
Original assignee: Hochschule Niederrhein
Priority date: 2018-11-07
Filing date: 2019-10-31
Publication date: 2020-05-14
Also published as: DE102018127736A1

Abstract

The invention relates to a device for feeding a thread for loop-forming tools, which are arranged in at least one row, of a textile machine, comprising a thread guiding device (4) having a rotary element (5), wherein the thread guiding device (4) is designed to move a weft thread (2) to and fro in two opposite directions in a feeding region (B) in each case in front of the row of tools. The thread guiding device is intended to create a device for feeding a thread over a partial width of a knitted web, wherein the device has a compact structure and allows a high working speed. This is achieved in that the thread guiding device (4) comprises at least one rotatably mounted roller (5) as a rotary element, wherein a groove system (6) is inserted into a lateral surface of the roller (5), said groove system running in a thread-like manner to and fro from a first end of the roller (5) to the opposite second end thereof as inflection points (6b).

Description

Device and method for presenting a thread

The invention relates to a device for presenting a thread for stitch-forming tools of a textile machine, which are arranged in at least one row. The device comprises a thread guide device with a rotating element, the thread guide device being designed to move a thread back and forth in a feed area in front of the row of tools in two opposite directions.

The invention also relates to a textile machine equipped with the device.

Furthermore, the invention relates to a method corresponding to the device.

A textile machine designed as a warp knitting machine, in particular as a Raschel machine, is described in DE 1 268 305 A, for example. A provided as a weft thread is presented by a thread guide of a long weft device, which is movable by means of an actuating cylinder between two reversal points, during a stitch formation process approximately parallel to the row of knitting needles on the back thereof. At the time of the knocking-off position of the needles across the row of needles, the weft thread is brought onto the front of the knitting needle row under the action of suction nozzles. Since the thread guide must be accelerated and braked between the reversal points, the speed at which the thread guide can be moved by means of the actuating cylinder is limited.

From DE 17 60 860 C3 a device for presenting weft threads for warp knitting machines, in particular for Raschel machines, is known, in which a thread guide guided on an orbit is provided. A rotary element designed as a rod is provided, at the end of which the thread guide is arranged. The rod is rotatable in a direction of rotation about an axis directed perpendicular to its direction of extension. The weft thread is guided from the bobbin through the axis of the rod to the thread guide. In the area of the web edges, holding elements are provided, around which the weft threads can be placed by the thread guide. The drive for the holding elements is matched to the rotational movement of the rod in such a way that the weft threads do not cross between the holding elements. The holding elements also serve as guide members for applying the weft threads to the warp threads.

Another warp knitting machine, in particular Raschel machine, with a device for inserting a weft thread is known from DE 1 920 477 A. The weft thread is placed outside of the needle zone by means of holding elements arranged in the area of the web edges and applied to the warp threads by means of guide members. Several thread guides guided in an orbit are provided to prepare the weft thread. see, each of which is assigned a spool holder rotating synchronously with it. Between the thread guides and the knitting needles, storage members are arranged to accommodate several weft thread lengths corresponding to the fabric width.

A device for providing weft threads on warp knitting machines is described in DE 20 35 007 A. The device comprises a thread guide consisting of a tube, which is guided by a circulating belt over reversal points in the area of the web. Storage devices are provided which take up the individual weft thread lengths and which are moved in the direction of the knitting tools.

A warp knitting machine, in particular Raschel machine, for the production of warp knitting goods with long weft threads with a device for the endless presentation of several weft threads is described in DE 24 01 050 A1. A carriage places the weft threads in conveyor belts arranged on both sides, through which the weft threads are guided to the knitting tools.

In modern textiles, particularly sports textiles, it is desirable and known to use mechanical, e.g. to achieve compressive properties. For this it is necessary to reinforce certain areas of the textile by using at least one additional thread or to provide them with special properties. This reinforcement or equipment is brought about by introducing the at least one additional thread, by plating a thread, by incorporating a weft thread and / or by changing the mesh structure.

The devices known for reinforcement or equipment are complex and require a lot of space.

So-called traversing rollers are known for winding a thread on a bobbin according to a predetermined pattern. They are e.g. in DE 2 429 055 B1, DE 41 30 996 C2 and DE 527 468 A. A large number of grooves are recessed into a lateral surface of the roller and cause a back and forth movement when the thread is deposited on the bobbin. The use of such rollers for presenting threads on a knitting machine is not known.

The object of the invention is to provide a device for presenting a thread over at least a partial width of a knitted fabric web, which is compact and which allows a high working speed.

The object is achieved in that the thread guide device has at least one rotatably mounted roller as a rotating element, a groove system being embedded in a lateral surface of the roller, which thread-like manner runs back and forth from a first end of the roller to its opposite second end as turning points . An axis of rotation of the roller is arranged parallel to a row of knitting tools and so relative to them that a thread running off the roll is presented to the knitting tools in a required position and has to cover the smallest possible distance from the knitting tools. The distance ideally corresponds to a radius of the roller plus a small play.

The groove system is designed such that it presents a thread running parallel to the knitting tools with a back and forth movement. Here, the course of the groove system - straight and / or curved - can cause differences in the effective feed speed. The weft thread is thus deflected by the roller during operation into a largely horizontal to-and-fro movement required for placing on stitch-forming tools. A distance from the turning curves of the groove system, which cause the turning points of the back and forth movement, corresponds to a width of the original area.

The thread guide device is thus designed to move the weft thread back and forth in two directions by means of tools of a textile machine that extend over a feed area. It is very simple and inexpensive and requires little installation space.

A very high working speed of the device can be set by an appropriate drive speed of the roller.

In warp knitting machines, the thread guide device with which a weft thread is fed back and forth can achieve weft thread speeds of, for example, 2,500 meters per minute. This speed is sufficient for certain warp knitting machines, for example for many Raschel machines, to feed the weft thread without an additional storage device. The use of this fast thread guide device offers new uses, e.g. B. in the fields of the production of nets, reinforcement textiles, geotextiles or lace.

The subclaims relate to the advantageous embodiment of the invention.

In one configuration, the device has a feed device which is designed to feed the thread laid in one direction to the tools. The feed device is designed, for example, as a gripper extending along the tools.

In a further embodiment, the device has a holding device with two holding elements which are spaced apart in the region of turning points (reversal points) of the thread of the serving area are arranged. Each holding element is designed to receive the thread laid in one direction by the thread guide device.

In one example, the holding device is designed to supply the held thread to the work. In an alternative example, a feed device is provided in addition to the holding device.

In a further embodiment, at least two of the rollers are arranged side by side and / or one behind the other in a thread running direction. This can e.g. a plurality of threads are laid next to one another and / or in regions one above the other, or a thread is transferred from a roller to an axially adjacent roller.

In a further embodiment, the groove system has crossings. The intersections have the effect that the groove system can be of complex construction and an angle of the thread guided in the groove system to a surface line of the roller is steeper. The targeted selection of the angle is particularly advantageous in turning curves of the groove system. In this way, a reliable guidance of the weft thread and an even presentation are achieved. A high presentation speed is possible.

In a further embodiment, the roller can be driven. As a result, the thread is guided even more safely and wear of the groove system and wear of the thread are minimized.

In a further embodiment, a thread guide is arranged in front of the roller. This makes it possible to arrange a bobbin, from which the weft thread is drawn, at a short distance from the roller, without there being a risk, particularly for turning areas, that the thread jumps out of the groove system.

In a further embodiment, a deflection means is arranged in front of the roller. This causes the thread to run onto the roller and into the groove system in a controlled manner.

A textile machine according to the invention with at least one row of stitch-forming tools has at least one device described above for a selection of adjacent tools.

Textile machines with stitch-forming tools, which are arranged in at least one row, are for example warp knitting machines, namely warp knitting machines, Raschel machines and crochet gallon machines, as well as sewing machines and flat knitting machines. A thread to be presented to the tools of a warp knitting machine or a sewing knitting machine or knitting tools or a flat knitting machine referred to as knitting tools is designed as a warp thread or as a weft thread. When the thread for the stitch-forming tools is presented, the thread laid at least in one direction is placed behind the tools. The at least one device is advantageously slidably attached to the textile machine. On the one hand, this makes retrofitting for arranging the weft transfer at another point in the effective width very easy. On the other hand, with the assistance of a motorized displacement and a corresponding control, an area of the weft laying can be automatically moved during the running operation of the textile machine.

A change in the height of the device or at least parts thereof can also be set up.

In one embodiment of the textile machine, in a side area outside the template area, a thread template is formed which is fed by the device.

The distance between the turning curves and thus the width of the roller is designed to be correspondingly larger. The fed thread can thus be temporarily stored in order to compensate for a thread length supplied during a needle movement.

The statements made apply accordingly to the method according to the invention.

The invention is further explained on the basis of the schematic drawing. Show it:

FIG. 1 the principle of a warp knitted fabric with a weft thread,

FIG. 2 shows a perspective view of a device for placing a thread,

Figure 3 shows an arrangement of several rollers and

Figure 4 is a side view of a textile machine designed as a warp knitting machine with the device.

An embodiment relates to a textile machine, which is designed as a warp knitting machine with a device for presenting a weft before arranged in a row knitting machine. The knitting tools form the tools here and the weft thread the thread.

FIG. 1 shows a section of a narrow band of a warp knitted fabric KG that can be produced by the warp knitting machine. In the example shown, the warp knitted fabric is made from eleven stitch-forming warp threads 1 and a weft thread 2. Two trimmed rows of stitches are shown above and below, as well as four complete rows of stitches with four weft reversal points 3. The weft thread 2 is guided through part of the stitches, namely through four stitches, and forms a reinforcement here.

Instead of the one weft thread 2, a plurality of weft threads 2 can be arranged one above the other and / or in areas lying next to one another - also partially overlapping.

The device for presenting the weft thread for the knitting tools 7 has a thread guide device 4, which is shown in FIG. 2. She is trained to Lay weft 2 in the area in front of the knitting tools 7, which extend over a feed area B, in two directions.

The thread guide device 4 has a roller 5 with a circular cross-section, which is rotatably mounted about an axis of rotation R such that the weft thread 2 running off the roller 5 is fed back and forth in front of the knitting tools 7 in a predetermined line area. For this purpose, there is preferably an upper or a lower surface line of the roller 5 in a horizontal plane with the line area, so that the weft thread 2 runs horizontally from the roller 5 to the knitting tools 7.

The roller 5 is e.g. of a motor can be driven so that its direction of rotation corresponds to the thread running direction FR.

A groove system 6 is embedded in a lateral surface of the roller 5. This comprises at least one groove 6a.

In the case of a single groove 6a, it is endless and extends in an X-ray view in the form of a rhombus, with turning curves 6b, which are arranged in both opposite end regions of the roller 5, being rounded. This shape of the groove system 6 is particularly suitable for rollers 5 with a large diameter and / or a short length.

The groove system 6 preferably comprises two grooves 6a, which are embedded in the thread-like manner and intersect in the lateral surface, as is shown in a very simplified manner in FIG. The groove system 6 is formed from the two opposite thread-like grooves 6a, the associated ends of which, as the turning curves 6b, merge into one another in a hyperbolic manner. A first of the grooves 6a is designed in the manner of a right-hand thread and a second of the grooves 6a in the manner of a left-hand thread, so that a plurality of crossings 6c of the two grooves 6a is formed. In each of the end regions of the roller 5, the two grooves 6a merge into one another and form a steep hyperbolic curve. In the area of the intersections 6c, the grooves 6a are designed in such a way that the weft thread 2 does not run incorrectly. A pitch is the same for both thread-like grooves 6a and is selected in accordance with a feed speed and a reliable guidance of the weft thread 2 in the grooves 6a.

The outer surface of the roller 5 has, at least in the grooves 6a and in areas adjoining them, a refined surface which on the one hand is low-wear and on the other hand smooth. For the finishing is e.g. a ceramic coating is suitable.

A thread template (not shown) can be formed on both sides of the feed area in order to temporarily store predetermined lengths of the weft thread 2. A length of the roller 5 corresponds to the length of the feed area B plus a predetermined edge area and possibly plus the lengths of thread templates. The diameter of the roller is as small as possible and is, for example, 2 cm to 20 cm.

A deflection means 9 is arranged in a thread running direction FR in front of the roller 5 and parallel to its axis of rotation R, which deflects the weft thread 2 in such a way that it hits the roller 5 at a suitable angle. The deflecting means 9 is here e.g. formed as a round bar 9 with a suitable surface.

A thread guide 10 can be arranged in the thread running direction FR in front of the deflection means 9, which guides the weft thread 2 such that an angle greater than 45 is formed between a tangent through a surface line in which the weft thread 2 meets the roller 5 and the thread course ° is. The thread guide 10 is parallel to the axis of rotation R of the roller 5 synchronously guided back and forth in synchronism with the feed directions and can be driven accordingly.

In some cases, the arrangement of a thread guide device between the roller 5 and the knitting tools is useful.

In a first position of the roller 5 shown in FIG. 2a, the warp threads 1 coming from above are guided around the latch needles 7 to form a next stitch above the latch 7a of the latch needle 7. The warp threads 1 each form a stitch below the tongue 7a of the tongue needle 7, into which a knitted section of the weft thread 2 (shown thickened) running from left to right in FIG. 2a is already accommodated. In FIG. 2a, the weft thread 2 is at the right weft reversal point 3.

In FIG. 2b, the weft thread 2 is in a position between the weft reversal points 3, which correspond to the turning points.

According to FIG. 2c, the warp thread 2 is laid in front of all associated latch needles 7, and the latch needles 7 are in a knock-off position; the warp thread 2 is at the left weft reversal point 3.

In many cases it makes sense to arrange a large number of rollers 5. In this case, the rollers 5 can be axially adjacent and / or vertically offset and / or arranged one behind the other in the thread running direction FR.

An example is shown in FIG. 3 with three of the rollers 5 and three of the weft threads 2. Each of the rollers 5.1, 5.2, 5.3 is assigned the associated weft thread 2.1, 2.2, 2.3, which is in each case removable from a bobbin 12.1, 12.2, 12.3. Here, the three rollers 5.1, 5.2, 5.3 are arranged in a horizontal plane, with a second 5.2 and a third of the bobbins 5.3 axially adjacent and a first 5.1 and the second of the bobbins 5.2 in the thread running direction FR are in a row. A first of the bobbins 12.1 is arranged above the other two bobbins 5.2, 5.3 so that the first weft thread 2.1 does not touch the second roller 5.2. This makes it possible to present the weft threads 2.1, 2.2, 2.3 in different areas and partially twice, that is, in a predetermined overlapping area, two of the weft threads 2.1, 2.2 are presented.

FIG. 4 shows the warp knitting machine with the device for placing the weft thread 2 in front of the knitting tools. The warp knitting machine is e.g. an RL Raschel machine with a series of knitting tools, where RL means right-left stitch sequence. The thread guide device 4 is arranged in the thread running direction FR in front of the knitting tools 7.

Of the knitting tools one of the latch needles 7, one of the knock-off boards 8, one of the piercing needles 1 1 and also one of the warp threads 1 are shown. The warp threads 1 are guided through the piercing needles 1 1 to the latch needles 7. The weft thread 2 is guided from the bobbin 12 through the thread guide 10 and over the deflecting means 9 and in the groove system 6 of the roller 5 and is laid in front of the latch needles 7 below the tongues 7a.

The warp knitting machine is indicated by a rear side wall 13 and a foundation 14. The warp knitting machine has a pair of rollers 15 and a winding tree 16 for pulling off the warp knitted fabric KG produced behind the knitting tools in the pull-off direction P.

In an alternative example, the warp knitting machine is designed as an RR Raschel machine with two rows of knitting tools. The warp knitting machine has a device for placing a weft thread for each of the two rows.

In operation, the weft thread 2 moves the weft thread 2 in two directions in the area in front of the knitting tools of the warp knitting machine which extend over the stroke width B.

The roller 5 of the thread guide device 4 is driven in accordance with the thread running direction FR. As a result of the guidance in the grooves 6a, the weft thread 2 is alternately laid in one of the directions and thus presented to an assigned part of the knitting tools. Here, the back and forth movement of the weft thread 2 for presentation to the tools is generated directly as the back and forth movement by the rotation of the roller 5 in connection with the guide in the groove system.

The preferably arranged thread guide 10 is driven in such a way that the weft thread 2 moves back and forth synchronously with the back and forth movement generated by the roller 5 to be placed between the bobbin 12 and the deflection means 9. As a result, an angle formed between the surface line of the roller 5 and the weft thread 2 becomes less acute, so that insertion of the thread into the groove system 6 becomes safer. Reference symbol list

1 warp thread

2 weft

3 weft reversal point 4 thread guide device

5 roller

6 groove system

6a groove

6b turning curve

6c crossing

7 latch needle

7a tongue

8 tee board

9 deflecting means

10 thread guides

1 1 hole needle

12 spool

13 side wall

14 foundation

15 pair of rollers

16 wrapping tree

B Feeding area FR Thread running direction KG warp knitted

P Direction of withdrawal R Rotation axis

Claims

1. Device for presenting a thread for stitch-forming tools of a textile machine arranged in at least one row,

with a thread guide device (4) comprising a rotary element (5),

the thread guide device (4) being designed to move a weft thread (2) back and forth in a feed area (B) in each case in front of the row of tools in two opposite directions,

characterized in that the thread guide device (4) has at least one rotatably mounted roller (5) as a rotating element, a groove system (6) being let into a lateral surface of the roller (5) and thread-like from a first end of the roller (5) whose opposite second end runs back and forth as turning points.

2. Device according to claim 1, characterized by a feed device which is designed to feed the thread laid in one direction (2) to the tools.

3. Apparatus according to claim 1 or 2, characterized by a holding device with two holding elements, which are arranged in the area of reversal of the thread at a distance from the entire feed area (B), the holding devices being designed to the one of the thread guide device (4) to pick up the thread (2) laid in the directions and feed it to the tools.

4. Device according to one of claims 1 to 3, characterized in that at least two of the rollers (5) are arranged side by side and / or in a thread running direction (FR) one behind the other.

5. Device according to one of claims 1 to 4, characterized in that the groove system (6) has crossings (6c).

6. Device according to one of claims 1 to 5, characterized in that the roller (5) is drivable.

7. Device according to one of claims 1 to 6, characterized in that the roller (5) is preceded by a thread guide (10).

8. Device according to one of claims 1 to 7, characterized in that the roller (5) is upstream of a deflecting means (9).

9. Textile machine with at least one row of stitch-forming tools, characterized in that at least one device according to one of claims 1 to 8 is arranged for at least some of the tools.

10. Textile machine according to claim 9, characterized in that the device is slidably attached to the textile machine.

1 1. Textile machine according to claim 9 or 10, characterized in that a thread template is formed in a side area outside the template area (B), which is fed by the device.

12. A method for presenting a thread for stitch-forming tools of a textile machine arranged in at least one row, characterized in that a back-and-forth movement of the thread (2) for placing on the tools is generated by rotation of a roller (5), the thread (2) being guided in a groove system (6) embedded in a lateral surface of the roller (5).