EP1777329A1 - Dummy shuttle loom - Google Patents

Abstract

A projectile loom has, on one or both sides of the shed, a thread tensioner (17) with several winding arms (39.1 - 39.8) for each weft thread supplied by the thread tensioner, each winding arm is being individually driven and preferably individually controlled. An independent claim is included for a variant of the loom, in which the thread tensioner has, for each weft thread supplied by the thread tensioner, at least one element inducing linear movement for tensioning, transfer onto a projectile and release of the warp thread.

Description

The invention relates to a projectile loom with at least one accelerating device for at least one projectile for the weft insertion.

In state-of-the-art projectile weaving machines, the energy for launching the projectile into the shed is usually provided by a torsion bar which is fixedly secured in the machine at one end and carries an accelerating member at its other end, with which the Projectile can be acted upon. Before firing the projectile, the torsion bar is twisted and then released. The result energy released is transmitted to the projectile via the acceleration element, thereby accelerating it. Such a weaving machine is for example in the EP 0 181 413 A1 described. A disadvantage of these known machines that the drive of the projectile on a torsion bar with accelerator brake has a relatively low efficiency.

From the US 3,868,976 is a projectile loom known in which the projectile for the weft insertion in alternation of both sides of the shed by compressed air is entered into this. The blowing of the projectile through the shed by means of compressed air, however, requires a considerable drive power and is therefore too expensive for practical use.

The present invention has for its object to provide a powerful and cost-effective projectile loom.

The object is achieved with a projectile weaving machine with at least one acceleration device for at least one projectile for weft insertion according to the invention that the acceleration device has a non-uniformly translating gear for driving a movable against the projectile acceleration element, which shoots the projectile in the shed formed during the weaving process and that the weaving machine has an acceleration device for the at least one projectile on both sides of the shed.

• Der Schussfadeneintrag kann somit von beiden Seiten in das Webfach erfolgen. Dazu ist es ausreichend, ein einziges Projektil vorzusehen, das im Wechsel von links und von rechts in das Webfach eingetragen wird. Dadurch entfällt die Vorrichtung zum Zurückführen der Projektile, wie sie bei Projektil-Webmaschinen mit einseitigem Schussfadeneintrag nach dem Stand der Technik erforderlich ist. Zwar sind bei einer solchen Ausgestaltung der Webmaschine zwei Beschleunigungsvorrichtungen erforderlich, doch werden diese jeweils weniger stark belastet als die Beschleunigungsvorrichtung einer Projektil-Webmaschine mit einseitigem Schussfadeneintrag, da immer ein Beschleunigungselement in Ruhe ist, während das andere Beschleunigungselement das Projektil beschleunigt. Die Vorrichtungen können somit schwächer ausgelegt werden und sind daher günstiger in der Herstellung als eine für eine Dauerbelastung ausgelegte Vorrichtung. Außerdem lassen sich durch das Vorsehen zweier Beschleunigungsvorrichtungen, die ein Projektil im Wechsel von links und von rechts in das Webfach eintragen, Webgeschwindigkeiten erreichen, die mit einer Projektil-Webmaschine mit einseitigem Schussfadeneintrag nicht zu erzielen sind. Ein weiterer Vorteil des beidseitigen Schussfadeneintrags liegt in der Möglichkeit, gleichmäßigere Gewebe herstellen zu können als mit Maschinen mit einseitigem Schussfadeneintrag, da die stets vorhandenen Spannungsunterschiede der Schussfäden zwischen der Eintragseite und der Austragseite bei zweiseitigem Schussfadeneintrag besser ausgeglichen werden können als bei einseitigem Schussfadeneintrag.

The replacement of the known torsion bar by a non-uniformly translating gearbox to provide the energy for the acceleration of the projectile increases the efficiency of the loom crucial. In contrast to a torsion bar, such a transmission also requires no oil cooling.

• The weft insertion can thus be made from both sides into the shed. For this purpose it is sufficient to provide a single projectile, which is entered alternately from the left and from the right in the shed. Thereby eliminates the device for returning the projectiles, as required in projectile weaving machines with one-sided weft insertion according to the prior art. Although in such an embodiment of the loom two accelerators are required, but these are each less heavily loaded than the accelerator of a projectile loom with unilateral weft insertion, there is always one accelerator at rest, while the other accelerator accelerates the projectile. The devices can thus be designed to be weaker and are therefore cheaper to manufacture than a designed for a continuous load device. In addition, by providing two accelerators which register a projectile alternately from left to right in the shed, web speeds can be achieved which are not achievable with a single-weft projectile weaving machine. Another advantage of the two-sided weft insertion is the ability to produce more uniform fabric than machines with one-sided weft insertion, since the ever-present differences in tension of the weft threads between the entry side and the discharge can be better compensated for two-sided weft insertion than one-sided weft insertion.

There is also the possibility of entering from the two sides of the shed and by means of two different clamping devices in the projectile weft threads of different colors and different qualities and thereby produce novel tissue.

For the design of the uneven translating gearbox different variants are conceivable. In a preferred embodiment, the gear may have eccentrically mounted and / or different from the round shape gears to achieve the required short-term high acceleration of the accelerator element. It may also be provided a curve drive.

In principle, the acceleration element, in this case a lever, can be used to accelerate the projectile via the central drive of the weaving machine. However, the accelerating device may also have its own motor, such as an electric motor, preferably an asynchronous motor. As a result, the energy necessary for the acceleration of the projectile can be made available immediately after the weaving machine has been switched on. The design of the transmission is easier in the presence of its own drive. It is understood that hydraulic or pneumatic drives for the accelerator device can be used.

The weaving machine according to the invention can also have in known manner on one or both sides of the shed a device for selecting the supplied from different yarn stores weft threads. In this case, the efficiency of the loom can be increased by the fact that the device for selecting the weft threads has a plurality of adjacently arranged and transversely to the weft insertion direction linearly displaceable thread tongs. Known devices for selecting a weft thread, in particular for color selection, have a plurality of rotationally adjustable thread clamps which optionally supply the projectile with its weft thread. However, the adjustment of these clamps is more complex than the linear displacement of the thread tongs in the selection device of the weaving machine according to the invention. In this case, this selection device can be used with advantage also in weaving machines with another principle of weft insertion, ie also in rapier looms or drag shuttle looms. Of course, the use in classic projectile weaving machines with a torsion bar drive of the projectile is possible.

Conveniently, a motor-driven traction means, preferably an endless rope or an endless belt may be provided for the displacement of the thread tongs on which the thread tongs are attached. Such a cable drive with a stepper motor is cheaper than a drive with a Linear motor. Chain and belt drives via one or two rollers can also be used.

Each of the thread tongs can optionally be brought into a selection position, from which it can be moved to the thread transfer to the projectile and thread takeover to the fabric edge. The selection position is in the extension of the longitudinal axis of the projectile. By transferring the weft thread from the selected thread tongs to the projectile, the weft thread remains constantly guided, i. it creates a so-called positive weft insertion. In addition, the picking up of the weft yarn at the fabric edge has the advantage that less weft yarn waste occurs.

For movement of the selected thread tongs on the projectile and / or on the fabric edge to and back to the selection position may be provided engageable with the selected thread pliers driver. This has the advantage that only one drive for the driver and not for all thread tongs is required.

Also, the driver can be attached to a driven traction means, preferably an endless rope or an endless belt, which can achieve the same advantages as in the movement of the thread tongs.

A further increase in the efficiency of the weaving machine according to the invention can be achieved by providing thread tensioner with a plurality of winding arms for each weft thread supplied by yarn stores on one or both sides of the shed, wherein the winding arms are individually driven and preferably driven individually. So far, thread tensioners are known in looms, which tension the weft by means of cams. In order to influence the different tensions of the different weft threads, the use of various cams is necessary. The loom must be shut down. With the new thread tensioners, however, an individual tension of the weft threads according to their properties even when the weaving machine is running possible. The thread tensioner according to the invention can also be used in other weaving machines not described here. Likewise, the thread tensioner according to the invention can be used alone wherever it is necessary to tension a single thread or several threads during the operation of a device. With the thread tensioner described here threads of different types can be individually tensioned or loaded.

For this purpose, the drive of the winding arms depending on the yarn properties of the individual weft threads can be controlled such that the thread tension remains constant or regulated variable. In particular, the timing and speed of winding can be adjusted individually to the individual yarn qualities.

In the weaving machine according to the invention may further be provided on both sides of the shed a device for braking the at least one projectile having two relatively movable jaws that clamp the projectile side and thereby decelerate. This device can be used simultaneously to hold the projectile in a defined launch position prior to launch. The jaws are open, but support the projectile from below and form a lateral guidance at the start.

In addition, projecting from below into the shed support elements may be provided which guide the at least one projectile during its flight through the shed from below and to the side. Known support elements for projectiles are C-shaped and therefore lead the projectile on the top, which, however, creates a higher friction and thus not as high speeds of the projectile can be achieved as in a leadership of the projectile exclusively from below and from the sides.

The projectile loom according to the invention can also be characterized by a new design of the projectiles for weft threads, which are different can optimize in terms of efficiency and cost. Thus, the at least one projectile can have a clamping device for a weft thread at both ends. The two clamping devices allow to enter the projectile from both sides in the shed, without having to rotate it beforehand. The clamping devices can also be designed differently, in particular have different clamping surfaces and clamping forces, so that weft threads of different quality can be entered. By providing two clamping devices at the ends of the projectile also the weft waste can be minimized.

Hereinafter, a preferred embodiment of a projectile weaving machine according to the invention will be described in more detail with reference to the drawing.

Fig. 1

eine perspektivische Ansicht der wesentlichen Komponenten einer erfindungsgemäßen Projektil-Webmaschine;

Fig. 2

eine Detailansicht der Beschleunigungsvorrichtung für das Projektil der Webmaschine aus Fig. 1;

Fig. 3 a, b

eine perspektivische Ansicht der Schussfaden-Auswahlvorrichtung der Webmaschine aus Fig. 1 in zwei verschiedenen Stellungen;

Fig. 4

eine vergrößerte Detaildarstellung zu Fig. 3 a;

Fig. 5

eine perspektivische Ansicht der Fadenspanner der Webmaschine aus Fig. 1;

Fig. 6

eine perspektivische Ansicht der Abbremsvorrichtung der Webmaschine aus Fig. 1.

Show it:

Fig. 1

a perspective view of the essential components of a projectile weaving machine according to the invention;

Fig. 2

a detailed view of the accelerator for the projectile of the loom of Fig. 1;

Fig. 3 a, b

a perspective view of the weft selection device of the loom of Figure 1 in two different positions.

Fig. 4

an enlarged detail of FIG. 3 a;

Fig. 5

a perspective view of the thread tensioner of the loom of Fig. 1;

Fig. 6

a perspective view of the braking device of the weaving machine of FIG. 1.

Fig. 1 shows a projectile loom 10 in its essential components in a perspective view. The projectile weaving machine 10 is designed for a weft insertion from both sides in the shed formed during the weaving process, which is indicated by two warp threads 12, 13. The shed, through which the projectile is transported, lies on the opposite side of the heald 43, which can not be seen in the figure. It has a symmetrical aggregate arrangement on both sides of the shed. Thus, two acceleration devices 14, 14 'for projectiles, two weft selection devices 15, 15', two braking devices 16, 16 'and two thread tensioning devices 17, 17' are provided. These units are shown and described more clearly in the following figures 2 to 6. In addition, in Fig. 1, the heald 43 of the loom 10 can be seen.

2 shows an enlarged detail view of the acceleration device 14 with an electric motor 18, which drives an acceleration element 20 via an unevenly translating gear 19, wherein the acceleration element 20 is movable against a projectile 21, in particular FIG. 4, and thereby shoots it into the shed , The transmission 19 shown here has a plurality of elliptical gears 22, 23, 24, 25, which are also mounted eccentrically. It can also be provided a cam drive to cause the momentary strong acceleration of the accelerator element. With the help of this transmission 19, the required short-term and strong acceleration of the acceleration element 20 can be achieved over a certain angular range.

The acceleration device 14 'arranged on the other side of the shed is constructed identically to the acceleration device 14.

FIGS. 3a, b show the weft selection device 15 of the weaving machine 10 from FIG. 1. In the example shown, the device 15 has eight juxtaposed thread tongs 26.1 to 26.8 off. Each of the thread tongs 26.1 to 26.8 is supplied from thread stores, not shown here, by means of eyelets 27 arranged in a plate (not shown), wherein the individual weft threads may differ from one another, in particular in color. The thread tongs 26.1 to 26.8 are releasably attached to an endless rope 28, which is guided over a deflection roller 29 and driven by a stepping motor 30. As a result, the thread tongs 26.1 to 26.8 can be moved transversely to the longitudinal direction of the projectile 21, so that each of the thread tongs 26.1 to 26.8 can be brought into a selection position in which it is located in the extension of the longitudinal axis of the projectile 21. In the example shown, the thread tongs 26.1 is in the selection position and at the same time has been moved from this to the projectile 21. In this position, the thread tongs 26.1 can pass the weft thread held by it to a clamping device of the projectile 21. After the transfer has been completed, the thread tongs move to the edge of the fabric in order to retain the weft thread after the entry (reduction of weft yarn waste). After the transfer, the thread tongs 26.1 moves back into the selection position in which it is again parallel to the other thread tongs 26.2 to 26.8. To move the thread tongs 26.1 to 26.8 on the projectile 21 to a driver 31 is provided which is engageable with each of those thread pliers, which is in selection position. The driver 31 is also attached to an endless cable 32 which is driven by an electric motor 33.

Fig. 3b shows one of the Fig. 3a corresponding representation, but now the thread tongs 26.3 has been brought into selection position and moved from the driver 31 to the projectile 21 to.

FIG. 4 shows the thread tongs 26.1 and the projectile 21 from FIG. 3a in an enlarged view. To pass the weft thread, the thread tongs 26.1 moves into a U-shaped recess 34 at the end of the projectile 21. In the U-shaped recess 34 a here not closer apparent clamping device of the projectile 21 is arranged, the weft of the Thread tongs 26.1 takes over. The clamping device of the projectile 21 is actuated by a lever 35 and a magnet arrangement 36. The projectile 21 is formed symmetrically to its central transverse axis 37 and therefore has at its other, not visible in Fig. 4 end also a clamping device which is actuated by a lever 35 '. From Fig. 4 can also be seen how the driver 31 engages with a projection 31.1 in a groove 38 on the underside of the thread pliers 26.1.

In Fig. 5, the thread tensioner 17 of the loom 10 is shown in more detail. He has a total of eight winding arms 39.1 to 39.8, which are each driven by a separate electric motor 40.1 to 40.8. Each of the winding arms 39.1 to 39.8 can wind the end of a weft thread as soon as the weft thread has been cut off. The end is held clamped by the thread tongs 26.1 to 26.8, the weft threads passing through the eyelets 27 coming from the winding arms 39.1 to 39.8. The winding arms 39.1 to 39.8 serve as a buffer for the weft yarns to keep the yarn tension constant. The single-motor drive of the winding arms 39.1 to 39.8 makes it possible to wind each weft individually according to its properties so that the thread tension remains constant. Switching to weft threads of other qualities is possible without conversion measures on the weaving machine and while the machine is running simply by a corresponding change in the control of the motors 40.1 to 40.8. In addition, it is by the thread tensioner 17 with the individually driven winding arms 39.1 to 39.8 easier to provide weft yarns of different qualities for the fabric, as in mechanically operating thread tensioners according to the prior art.

Fig. 6 finally shows the braking device 16 in an enlarged view. The braking device 16 has two clamping jaws 16.1 and 16.2, which are movable relative to one another in the direction of arrows 16.3 and the projectile 21 can pinch between them. Are the jaws 16.1, 16.2, as shown in Fig. 6, open, they support the projectile 21 in the firing position both laterally and from below. These are in the Jaws 16.1 and 16.2 respectively provided grooves 41.1 and 41.2, in which the projectile 21 can be performed as in rails. In the firing position of the projectile 21 shown in FIG. 6, the acceleration element 20 of the accelerator 14 can be moved against the end of the projectile 21 and thereby shoot it into the shed 11. To guide the projectile 21 in the shed projecting from below into the shed and in particular from the figures 3a, b support members 42 are provided which support the projectile 21 during its flight through the shed 11 from below and laterally. For this purpose, the support elements 42 are formed substantially U-shaped. About the jaws 16.2, a guide rail 44 is arranged, which leads the respective thread pliers, here the thread tongs no. 1, from the selection position in a transfer position of the weft thread to the projectile 21 to the fabric edge and back to the selection position. The endless cable 32, which holds the driver for the thread pliers, is held on a support 45 via deflection rollers.
46 shows the front opener for the thread tongs, which takes over the weft thread near the fabric edge. After the takeover, the weft is cut off. The necessary cutting device is not shown in the figure.

A projectile loom 10 having two accelerators 14, 14 'for at least one weft insertion projectile, wherein at least one accelerator 14, 14' comprises a non-uniformly translating gear for driving an acceleration member 20 movable against the projectile, which projects the projectile into the during the Web operation formed shed 11 shoots, and that on both sides of the shed 11 each have an accelerator 14, 14 'is provided.

Claims (14)

Projectile weaving machine with at least one accelerating device (14, 14 ') for at least one projectile (21), characterized in that the accelerating device (14, 14') has a non-uniformly translating gear (19) for driving one against the projectile (21) Acceleration member (20) which shoots the projectile (21) into the shed formed during the weaving operation, and has on both sides of the shed an accelerating device (14, 14 ') for the at least one projectile (21). Projectile weaving machine according to claim 1, characterized in that the non-uniformly translating gear (19) eccentrically mounted and / or deviating from the round shape gears (22 to 25). Projectile weaving machine according to claim 1 or 2, characterized in that the accelerating device (14, 14 ') has a motor, such. B. an electric motor (18), preferably an asynchronous motor having. Projectile weaving machine according to one of claims 1 to 3, characterized in that it comprises on one or both sides of the shed a device (15, 15 ') for selecting the weft threads supplied from different yarn stores. Projectile loom according to claim 4, characterized in that the device (15, 15 ') for selecting the weft threads a plurality of juxtaposed and transversely to the weft insertion direction linearly displaceable thread tongs (26.1 to 26.8). Projectile weaving machine according to claim 5, characterized in that for displacement of the thread tongs (26.1 to 26.8) a motor-driven traction means, preferably an endless rope (28) or endless belt is provided, to which the thread tongs (26.1 to 26.8) attached are. Projectile weaving machine according to claim 5 or 6, characterized in that each of the thread tongs (26.1 to 26.8) is selectively engageable in a selection position, from which it is to thread transfer to the projectile (21) and thread takeover on the fabric edge to move. Projectile loom according to claim 7, characterized in that the selected thread pliers (26.1, 26.8) by means of a driver (31) on the projectile (21) and / or on the fabric edge to and back into the selection position is movable. Projectile loom according to claim 8, characterized in that the driver (31) is attached to a driven traction means, preferably an endless rope (32) or endless belt. Projectile weaving machine according to one of claims 1 to 9, characterized in that it has on one or both sides of the shed thread tensioner (17, 17 ') with several winding arms (39.1 to 39.8) for each weft yarn supplied by thread stores, wherein the winding arms ( 39.1 - 39.8) are driven individually and are preferably controlled individually. Projectile weaving machine according to claim 10, characterized in that the drive of the winding arms (39.1 to 39.8) in dependence on the thread properties of the individual weft threads can be controlled such that the thread tension remains constant or regulated variable. Projectile weaving machine according to one of claims 1 to 11, characterized in that on one or both sides of the shed, a device (16, 16 ') for braking the at least one projectile (21) is provided, the two relatively movable jaws ( 16.1, 16.2), which laterally clamp the projectile (21) and thereby decelerate. Projectile loom according to one of claims 1 to 12, characterized in that it projects from below into the shed supporting elements (42) which guide the at least one projectile (21) during its flight through the shed from below and laterally. Projectile loom according to one of claims 1 to 13, characterized in that the at least one projectile (21) to its central transverse axis (37) has at both ends a clamping device for a weft thread.

Images