GB1566033A

GB1566033A - Weft insertion device

Info

Publication number: GB1566033A
Application number: GB1856177A
Authority: GB
Original assignee: JAEGER E KG
Current assignee: JAEGER E KG
Priority date: 1977-05-03
Filing date: 1977-05-03
Publication date: 1980-04-30

Description

(54) WEFT INSERTION DEVICE (71) We, EMIL LAGER KG, a German Company, of Dahlweg 105, 4400 Minster, Federal Republic of Germany, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The invention relates to looms, and is concerned with a device for clamping the weft in looms. It relates particularly, although not exclusively, to wire weaving looms. In wire weaving looms it is necessary to overcome the problems arising from the insertion of a wire, particularly a metal wire, as opposed to textile thread.

In the textile industry weaving looms are known which work with a gripper shuttle which pulls off the weft from supply bobbins disposed in fixed positions on both sides of the loom. In arrangements of this kind a great problem is that of ensuring correct taking-over of the weft by the gripper shuttle.

According to the present invention there is provided a weaving loom having stationary weft bobbins, having cutting means to sever the weft after being drawn into the fabric, and a shuttle equipped with gripper means for gripping the weft, the loom having means for holding a weft thread and presenting it for transfer to the shuttle, which means are movable, in timed relation to the reciprocating movement of the shuttle, between a first position for holding a weft thread so as not to obstruct the passage of the shuttle and a second position for holding the weft thread in the path of the gripper means for transfer of the weft thread to the shuttle, the said means consisting of or incorporating a clamp device whose travel between the two positions is solely by a pivotting movement about an axis extending in the direction of the warp threads, and having an angled form with a first arm disposed transversely to the warp direction and a second arm extending from the first in the warp direction, and provided with means for clamping the weft over which, in use, the said gripper means of the shuttle pass to take the weft thread.

By this means it is possible to dispose the thread gripper means of the shuttle inside the shuttle body, while the actual clamping device is now disposed in the vertical plane of the shuttle and, as the shuttle runs in and out, makes only a swivelling movement by which the thread is brought into the pick-up range of the gripper of the shuttle. Suitably the shuttle has a said gripper means at each of its ends, and the first and second arms are vertical and horizontal respectively.

By contrast the weft cutting and clamping device disclosed in our German Patent Specification 2216 528 shows a weft insertion device for use with a shuttle having its means for catching and gripping weft thread disposed laterally at one edge. This clamping and cutting device not only performs a swivelling movement about an axis extending in the warp direction, transversely of the direction of movement of the shuttle but also performs a translatory movement in a direction transverse to the direction of movement of the shuttle.

In a loom according to the present invention, the cutting device and the clamp device may be operated by a pneumatic piston and cylinder arrangement, it having been found that an arrangement of this kind permits rapid operation with little risk of breakdown.

The clamp device may swivel around a said pivot axis which is at one end of the first arm, with the second arm at the opposite end, and the device turning through 90" between the two positions. An alternative possibility will be mentioned below however.

In many situations in weaving it is necessary for a plurality of weft threads coming from different supply bobbins to be inserted parallel to one another. If for example two bobbins are disposed on each side of the fabric web, four weft threads are therefore inserted one after the other each coming from a different magazine, so that if there should happen to be a fault in the material of one of these threads, this fault will be repeated at only every fourth thread in the woven fabric. It is also possible to obtain determined material properties of the fabric by inserting threads having different characteristics.

Although mention is made above of two threads, it is obvious that this number can be increased as desired and that, for example, three, four, or even more magazine bobbins may be used on each side of the fabric.

A further development of the invention provides means by which weft threads coming from different supply bobbins disposed on one and the same side of the fabric can be inserted.

To enable this there may be employ an assembly comprising a plurality of said clamping devices for respective independent weft threads, the devices being independently pivotable about a common swivel axis to effect the said pivotting movement, and being displaceable in the warp direction i.e. transversely of the longitudinal axis of the weft thread so that different clamp devices and their respective weft threads can be brought into the path of the gripper means of the shuttle.

In. this arrangement it is advantageous for each clamp device to be so arranged that the swivel axis is not at the end of the said first arm of the clamp device but is offset in the opposite direction to the direction of insertion of the weft thread.

It is then possible for each clamp device no longer to need to make a movement of 90Q, but only one of 30 to 75", so that in this way a saving of time is achieved which is sufficient, for example, to enable the aforesaid displacement of the clamp. device in the warp direction to take place - during the time available.

When such an assembly comprises two clamp devices, a mode of operation can adopted in- which one or- the other clamp device can be used alternately for the in sertion of a weft thread. It is obviously also possible to use only one clamp device continuously for a certain period of time, while for example the other clamp device is kept in readiness as a replacement or reserve device, or determined weave effects can be achieved by using one type of weft thread for a certain length of time, thereupon changing over and then moving the clamp device with the other weft thread into the working position.

To a weaving specialist it is obvious that the most diverse combinations can be achieved in this manner, within the scope of protection of the invention.

In order to ensure undisturbed supply of the weft thread despite the transverse movement of the clamp device, it is preferred that each weft thread should be guided through a thread guide duct formed in a respective member carrying the clamp device for that thread and through which the swivel axis passes; e.g. the member carrying a pivot pin. This thread guide duct may be in the form of a bore.

Two embodiments of the invention will be described below, by way of example, with reference to the drawings, in which: Figure 1 is a view in perspective of a cutting and clamping device, Figure 2 is an elevational view of parts of the device with the clamp open, Figure 3 an elevational view of parts of the device with the thread clamped, the clamp device having brought the thread into the position of readiness for catching by the gripper of the shuttle, Figure 4 is a view in perspective of a second apparatus for clamping weft thread.

Figure 5 shows the so-called holding position of this apparatus, and Figure 6 shows one of the units of this apparatus in the so-called transfer position.

Referring first to Figs. 1 to 3 of the drawings, 1 designates generally a clamping and cutting device which comprises the actual clamp device 2 and the actual cutting device 3. At 4 is indicated a thread guide which in the embodiment illustrated consists of a profiled roller under which is guided the weft thread which is to be inserted and which comes from the magazine bobbin (not shown, but lying to the right of Figures 2 and 3). In the drawing the thread itself is designated 5.

The clamp device 2, as can be seen from Figures 2 and 3, is of angled form. It is pivotable about an axis 14 which extends substantially parallel to the direction of the warp threads (not shown) and has a first arm extending transversely to the pivot axis, and hence transversely to the warp direction also and a second arm extending from'the first arm ih a direction parallel to the pivot axis. As seen in Fig. 3 the first arm- extends down vertically and the second arm extends horizontally from it. As best seen from Fig. 2 the two arms are each formed by two parts which are relatively movable so as to provide clamp jaws 10, 11 in the second arm, for clamping the weft thread.

Part of a gripper shuttle is designated 6 in Figure 3, and it can be seen that the interior of the shuttle 6 contains, at one end, a thread catching and gripping device 7, which may be of a type known per se and therefore will not be explained more fully here.

From the illustration in Figure 1 it is also possible to see four cylinders, which are part of pneumatic piston and cylinder arrangements. The cylinder 8 effects the pivotting movement of the actual clamp device 2, around its axis 14 while the purpose of the cylinder arrangement 9 is to operate the two clamp jaws 10 and 11; the cylinder arrangement 12 serves the purpose of operating the shears of the cutting device 3, and whose construction can be seen more clearly in Figure 2, and the cylinder arrangement 13 serves to open or close the thread catching and gripping device 7 of the shuttle.

The clamp device 2 pivots around tlie axis 14 in timed relation with movement of the shuttle. The device 2 pivots between a holding position, shown in Figure 2 in which the device takes hold of the weft thread, and a transfer position shown in Figure 3. In the holding position (Figure 2) the clamp device, and the weft thread are held clear of the path of the shuttle, while in the transfer position the clamping de vice extends into the interior of the shuttle and thus holds the thread S presented ready for picking up by the catching and gripping device 7 of the shuttle (Figure 3). The thread is then taken over by the catching and gripping device 7 as the shuttle moves towards the warp threads (to the left as seen in Figure 3).As the shuttle moves in this direction its catching and gripping device 7 passes over the second arm of the clamp device 2, encounters the weft thread 5 held by the jaws 10, 11 and picks up this thread. The picked up weft thread is carried away by the shuttle in the manner described in detail, in our German Patent Specification 2,216,528, particularly in connection with Figure 8. After the weft thread 5 has been drawn into the fabric it is severed by the device 3, and picked up by the clamping device 2 in the holding position of the letter, as shown in Figure 2, ready to be presented again to the shuttle. It will be appreciated that movement of the clamp device 2 between these two positions is solely by pivotting.

In Figures 4 to 6, the references 21 and 22 designate two units for holding respective weft threads and presenting one or other of them for transfer to the shuttle.

The units each incorporate a clamp device in accordance with this invention. The two units 21, 22 are disposed side by side and are substantially of identical construction, although partly in a mirror image arrangement, so that hereinbelow there will be described more fully only one of these units namely the unit 22.

The unit 22 consists of a main body 23 which is carried by a displacing device 24, being hinged thereto by way of the pivot pin 26 which is offset in the opposite direction to that of insertion of the weft thread, in relation to the actual clamp device carried by the body 23, and which is indicated by the very general reference 27. At 28 is shown the part of a gripper shuttle which is equipped with a thread catching and gripping device, namely gripper tongs 29 shown very generally, which serve to take over and hold a weft thread 30.

The construction of the actual clamp device 27 can be seen more clearly in Figure 6. This clamp device 27 is of angled form, and consists of a first vertical arm 31 and a second, horizontal arm 32, the horizontal arm 32 being provided with the actual thread clamp 33. The weft thread 30 passes through the body 23 entering at the thread inlet 34 and travelling through a thread guide duct 35 provided inside the main body 23.

A cutting device for severing the weft thread after it has been drawn into the fabric is shown diagrammatically at 36.

As mentioned, the units 21, 22 are carried by a displacing device 24 which can make translatory movement to shift the two units parallel to the warp threads over a distance such that either the clamp device 27 of the unit 22 or the clamp device of the unit 21 comes into line with the path of the gripper tongs 29 of the gripping shuttle 28. The various movements required are made with the aid of pneumatic piston and cylinder arrangements indicated diagrammatically in the drawings, while it is, however, plainly also possible to use other drive means. This displacement of the units enables selection of one of the two warp threads carried by the units. The selected thread can then be transferred to the shuttle by operation of the unit which holds it.

The units 21, 22 can each pivot around the swivel axis 26 between a lowered position and a raised position turned 45" in relation to the lowered position. Figures 4 and 6 show the unit 21 in this raised position and the unit 22 in the lowered position.

In the raised position of a unit, that unit's actual clamp device lies entirely out of the path of the gripping shuttle 28. The lowered position is a transfer position in which the thread is presented for picking up by the shuttle.

In use, when one or other of the units 21, 22 is in line with the path of the gripper tongs 29 of the gripper shuttle 28, this unit -- for example the unit 22 as shown in Figure 6 -- makes a movement of from about 30 to 75" about the swivel axis 26 (in timed relation with movement of the shuttle) out of the raised position shown in Figure 5, in which it was clear of the path of the shuttle, into the position shown in Figure 6, which is such that the clamp device 27 extends into the interior of the gripper shuttle 28 and consequently holds the actual weft thread 30 presented ready for the gripper tongs 29 (working position as shown in Figure 6).As the shuttle 28 moves towards the warp threads (to the right of Figure 6) its gripper tongs 29 pass over the second arm 33 of the clamp device 27. The weft thread 30 is now gripped and taken over by the gripper tongs 29 of the shuttle 28 and then inserted into the actual shed.

The weft insertion devices described above are of simple design and allow use of a shuttle in which the thread catching device is disposed inside the shuttle body.

WHAT WE CLAIM IS: 1. A weaving loom having stationary weft bobbins, having cutting means to sever the weft after being drawn into the fabric, and a shuttle equipped with gripper means for gripping the weft, the loom having means for holding a weft thread and presenting it for transfer to the shuttle, which means are movable, in timed relation to the reciprocating movement of the shuttle, between a first position for holding a weft thread so as not to obstruct the passage of the shuttle and a second position for holding the weft thread in the path of the gripper means for transfer of the weft thread to the shuttle, the said means consisting of or incorporating a clamp device whose travel between the two positions is solely by a pivotting movement about an axis extending in the direction of the warp threads, and having an angled form with a first arm disposed transversely to the warp direction and a second arm extending from the first in the warp direction, and provided with means for clamping the weft over which, in use, the said gripper means of the shuttle pass to take the weft thread.

2. A loom according to claim 1 wherein the shuttle has a gripper means at each of its ends.

3. A loom according to claim 1 or claim 2 wherein the clamp device and cutting means are operated by pneumatic piston and cylinder means.

4. A loom according to any one of the preceding claims having a plurality of said clamping devices for respective independent weft threads, the devices being independently pivotable about a common swivel axis to effect the said pivotting movement, and being displaceable in the warp direction to bring a selected one of the weft threads into the path of the gripper means of the shuttle.

5. A loom according to claim 4 wherein each weft thread is guided through a duct in a respective member carrying the clamp device for that thread and through which passes the said swivel axis.

6. A loom according to any one of the preceding claims wherein the or each clamp device pivots through 30 to 750 in moving between the two said positions.

7. A loom according to any one of the preceding claims and having means for clamping weft thread substantially as herein described with reference to Figs. 1 to 3 or Figs. 4 to 6 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. unit -- for example the unit 22 as shown in Figure 6 -- makes a movement of from about 30 to 75" about the swivel axis 26 (in timed relation with movement of the shuttle) out of the raised position shown in Figure 5, in which it was clear of the path of the shuttle, into the position shown in Figure 6, which is such that the clamp device 27 extends into the interior of the gripper shuttle 28 and consequently holds the actual weft thread 30 presented ready for the gripper tongs 29 (working position as shown in Figure 6). As the shuttle 28 moves towards the warp threads (to the right of Figure 6) its gripper tongs 29 pass over the second arm 33 of the clamp device 27.The weft thread 30 is now gripped and taken over by the gripper tongs 29 of the shuttle 28 and then inserted into the actual shed. The weft insertion devices described above are of simple design and allow use of a shuttle in which the thread catching device is disposed inside the shuttle body. WHAT WE CLAIM IS:

1. A weaving loom having stationary weft bobbins, having cutting means to sever the weft after being drawn into the fabric, and a shuttle equipped with gripper means for gripping the weft, the loom having means for holding a weft thread and presenting it for transfer to the shuttle, which means are movable, in timed relation to the reciprocating movement of the shuttle, between a first position for holding a weft thread so as not to obstruct the passage of the shuttle and a second position for holding the weft thread in the path of the gripper means for transfer of the weft thread to the shuttle, the said means consisting of or incorporating a clamp device whose travel between the two positions is solely by a pivotting movement about an axis extending in the direction of the warp threads, and having an angled form with a first arm disposed transversely to the warp direction and a second arm extending from the first in the warp direction, and provided with means for clamping the weft over which, in use, the said gripper means of the shuttle pass to take the weft thread.