EP0131481A1 - Weft mixer for looms - Google Patents

Abstract

The invention relates to the textile industry and, more specifically, weaving machines. The weft yarn mixing device comprises: general control means (11, 18, 24, 26, 28, 32, 34); a rocker arm (6) connected to each dispensing finger (2); a drawer (56) and a pusher (58) for placing the corresponding rocker arm in the active position; a drawer (57) and a pusher (59) for placing the same rocker arm in the inactive position; rods (71) for selective connection of an axis (34) of the general control means to the corresponding drawers for placing in active position or for placing inactive position according to one of two possible positions of said push rods; and individual electromagnets (76) for controlling the position of each of the push rods. The invention is applicable to weaving machines on which it is necessary to mix the weft threads.

Description

The invention relates to weft yarn mixing devices which allow different wefts, possibly of different colors, to be inserted from a feed located outside a weaving machine.

Usually, devices of this kind include a support to be fixed on the machine and on which are mounted: a plurality of fingers for presenting the different weft threads adapted to each take, selectively, either an active active position for presenting a thread corresponding frame, ie a retracted inactive position; individual first means / of positive control for bringing each presentation finger into the advanced active position; second individual control means for returning each presentation finger to its retracted inactive position; general control means of the aforementioned first individual control means, adapted to be connected to the main shaft of the machine to operate in synchronism with said shaft; means for selective connection between the general control means and the first individual control means; and programmed selection control means suitable for controlling said selective link means.

However, in known devices of this kind, the aforementioned second individual means for controlling the return of each presentation finger to its retracted inactive position are constituted by a spring, or equivalent means, which is released in response to positioning. active with another presentation finger. Such a technique can no longer be suitable for modern weaving machines at very fast speed, because the return of the presentation finger to its inactive position, under the simple action of a spring, is no longer done quickly enough and the weft mixing mechanism is no longer able to correctly follow the rate imposed by the weaving machine.

The object of the invention is to remedy the aforementioned drawback of the known devices in question.

To this end, according to the invention, the individual means for controlling the return of each presentation finger to its retracted inactive position are also positive control means also subjected to the action of the selective connection means, and each presentation finger is connected to a rocker arm subjected to the programmed antagonistic actions of the individual means for placing in active and inactive positions, respectively.

Thanks to this new design, the return movements of the weft presentation fingers are ensured in a coercive manner as fast as their forward movement and this in perfect synchronism with the other parts of the machine, in particular the mechanism of insertion of the weft threads, that is to say under the best operating safety conditions.

The invention will be better understood on reading of the description which follows and on examining the appended drawings which show, by way of example, an embodiment of the invention.

• la figure 1 est une vue de profil d'un dispositif mélangeur de fils de trame suivant l'invention,
• la figure 2 est une vue en plan partielle montrant un détail de la partie supérieure gauche de la figure 1,
• la figure 3 est une coupe horizontale partielle faite suivant la ligne III-III de la figure 1, et
• la figure 4 représente la partie principale de la figure 1 pour une position différente des moyens de liaison sélective.

In these drawings:

• FIG. 1 is a side view of a weft yarn mixing device according to the invention,
• FIG. 2 is a partial plan view showing a detail of the upper left part of FIG. 1,
• FIG. 3 is a partial horizontal section taken along line III-III of FIG. 1, and
• Figure 4 shows the main part of Figure 1 for a different position of the selective connection means.

The weft yarn mixing device for a weaving machine shown in FIG. 1 is mounted on a support 1 to be fixed on the machine; it includes a plurality of fingers such as 2, for presenting the different weft threads, eight in number, for example. The finger 2 can slide in a hole 3 of the support 1, its distal end has an eye 4 for receiving a weft thread, while its proximal end is articulated, by an axis 5, on a rocker arm 6 which can pivot on an axis 7 carried by the support 1. The finger 2 can take, selectively, either a remote inactive position which is that shown in solid lines in the drawing, or an advanced active position for presentation of the corresponding weft yarn which is that shown in broken lines in 2A. It is brought positively from its inactive position to its active position by a pivoting movement of the rocker arm 6 in the direction of arrow f and it is brought back, also in a positive manner, from its active position to its inactive position, by a pivoting movement of the rocker arm in the opposite direction to that of arrow f. In the drawing, finger 2 is shown rectilinear, while other fingers, such as 2B and 2C, are shown curved and this so that the different fingers present their weft threads in substantially the same location, moreover possibly several threads at the same time, for example two.

Each presentation finger is associated with a rocker arm; thus, the different fingers 2, 2B and 2C, for example, are associated, respectively, rockers 6, 6B and 6C (see also Figure 3).

The rocker rocker movements, such as 6, are ensured, from general control means, by means of selective connection means and individual control means.

The general control means comprise: a grooved cam 11, a shaft 12 which rotates in a bearing 13 integral with the support 1 and on which the cam 11 is fixed, a toothed pulley 14 also fixed on the shaft 12, a toothed belt 15 which passes over the toothed pulley 14 and over another pulley (not shown) connected to the main shaft of the machine, so that the cam 11 rotates in synchronism with said main shaft of the machine; a roller ₁ 7 housed in the groove of the cam 11, a lever i8 with two arms 19, 21 which pivots, by its top, on an axis 22 also carried by the support 1, an axis 23 which is mounted on the end of the arm ₂ 1 and which carries the roller 17, a pin 25 mounted on the end of the other arm 19 of the lever with two arms, a connecting rod 24 whose one end is articulated on the axis 25, a crank 26 whose hub 27 (see also figure 2) is mounted idly to rotation and sliding on a shaft 28 which pivots on the support 1, a pin 29 mounted in the end of the crank 26 and on which the other end of the connecting rod 24 is articulated, another crank 32 fixed on the shaft 28 and whose end has a central groove 33, and a transverse axis 34 engaged in the groove 33 and provided with pads 35 engaged in a slide 36 of the support 1. The connection between the hub 27 of the crank 26 and the shaft 28 is done by a disengageable system which comprises a pin 41 fixed transversely in the shaft 28 and engaged in a diametrical groove 42 formed in one face of the hub 27 of the crank. A spring 43, interposed on the shaft 28 between the support 1 and the hub of the crank, biases the latter axially against the pin 41. The disengagement of this system is obtained by a thrust exerted, in the direction of the arrow f2 ( FIG. 2), on the hub 27 of the crank, against the force of the spring 43. For this purpose, a mechanism is provided which makes it possible, at the same time, to disengage the general mechanical control which has just been describe, and replace it with a general manual command. This mechanism comprises: a bush 45 also mounted with free pivoting and sliding on the shaft 28 next to the hub 27 of the crank 26 and whose face adjacent to said hub also has a diametrical groove 46 capable of engaging on the pin 41, when the sleeve 45 is pushed against the hub 27 of the crank, under the action of a handle 47 which is pivotally mounted on a transverse axis 48 planted in the sleeve 45 and which has an extension 51 whose end is engaged in an arc-shaped light 52 formed in a guide 53 secured to the support 1, in the form of portion of cylindrical surface, coaxial with the shaft 28, which allows the shaft 28 to be pivoted by means of the lever previously pushed in the direction of the arrow f2 to ensure disengagement of the mechanical control.

The individual means for controlling the weft presentation fingers have a positive action in both directions. They comprise, for each finger, for example for finger 2 associated with the rocker arm 6, an active positioning drawer 56 and an inactive positioning drawer 57 connected to the rocker arm 6 by two pushers 58, 59, respectively. The two drawers 56 and 57 are slidably mounted in slides 61, 62 fixed on the support 1. The two pushers 58, 59 are engaged, by one of their rounded ends, in the bottom of corresponding rounded notches 63, 64 formed in the two drawers, and, at their other end, in the form of a cylindrical head 65, 66, in bores in the form of corresponding cylindrical surface portions 67, 68 formed in the rocker arm 6.

The means for selective connection between the general control means and the individual means for controlling the presentation fingers which have just been described comprise, for each finger, a push rod 71 whose proximal end is articulated on the axis 34 of the general control means, the distal end of which, cut at a bevel 72 (see also FIG. 4), can engage, selectively, either in a notch 73 of the upper drawer 56 for placing the corresponding finger in active position when said push rod occupies its high position shown in Figure 4, either in a notch 74 of the lower drawer 57 for setting inactive position of the finger when the push rod occupies its low position as shown in FIG. 1.

The passage of each push rod, such as 71, from its low position to its high position, is done under the control of programmed selection control means. These means comprise, for each push rod, an individual electromagnet 76 fixed on the support 1, assisted by a spring 77 which tends to move the push rod away from the poles of the electromagnet. In order to facilitate the work of the electromagnet, mechanical means are provided which automatically and positively bring each push rod into contact with the poles of the corresponding electromagnet, at the end of each recoil movement of the rod. These means comprise a cam 78 on the push rod 71, which cooperates with a fixed stop 79 secured to the support 1, the locations of the cam on the push rod and the stop on the support, as well as the configuration and the dimensions. of said cam, being such that, only when the push rod reaches the end of its recoil stroke, under the action of the general control means, it is raised positively, under the effect of said cam, against the poles of the electromagnet 76.

In addition to the programmed selection control means by the electromagnets 76, the device comprises manual selection control means in the form of individual selection levers associated with each of the push rods; these levers such as 81 or 82, for example, associated with the push rods 71, 71B for controlling the presentation fingers 2, 2B respectively, are pivotally mounted on a common axis 83 carried by the support 1, and are located just below the corresponding push rods. Thus, when one exerts, by hand, on the outer end of these levers, a vertical thrust from top to bottom, that is to say in the direction of the arrow f3 in FIG. 1, the end inside the lever keeps the corresponding push rod 71, 71B raised against the return spring 77, as long as the manual push is maintained on the lever.

• On suppose que la machine à tisser sur laquelle il est monté est en fonctionnement et que la dernière trame qui vient d'être insérée dans la foule est celle qui a été présentée par le doigt 2B, la tige de poussée 71B vient d'être amenée en position avancée par la came 11, de sorte que les organes correspondants (tiroir supérieur, poussoir supérieur et culbuteur) ont été amenés dans leur position active pendant que les autres organes, c'est-à-dire les tiges de poussée telles que 71, les tiroirs inférieurs tels que 57, et les poussoirs inférieurs tels que 59, également amenés en position avancée, ont placé tous les autres culbuteurs, tels que 6 et, par conséquent, les doigts de présentation correspondants, en position inactive (figure 1). La came 11 est entraînée en rotation en synchronisme avec l'arbre principal de la machine, de sorte que, lorsque la bosse de ladite came va s'engager contre le galet 17, elle va le repousser et tout l'ensemble des moyens généraux de commande décrits plus haut vont provoquer le recul de l'axe transversal commun 34 et, par conséquent, le recul de toutes les tiges de poussée telles que 71 et, en fin de course, leur remontée contre les électro-aimants tels que 76 sous l'effet des butées 78, comme représenté sur la figure 4. A ce stade du fonctionnement, deux hypothèses sont à envisager

The operation of the frame mixing device is as follows:

• It is assumed that the weaving machine on which it is mounted is in operation and that the last weft which has just been inserted into the crowd is that which was presented by the finger 2B, the push rod 71B has just been brought in the advanced position by the cam 11, so that the corresponding members (upper drawer, upper pusher and rocker arm) have been brought into their active position while the other members, that is to say the push rods such as 71 , the lower drawers such as 57, and the lower pushers such as 59, also brought into the advanced position, have placed all the other rocker arms, such as 6 and, consequently, the corresponding presentation fingers, in the inactive position (FIG. 1) . The cam 11 is rotated in synchronism with the main shaft of the machine, so that when the hump of the said cam will engage against the roller 17, it will push it back and all of the general means of control described above will cause the common transverse axis 34 to recede and, consequently, the recoil of all the push rods such as 71 and, at the end of their travel, their ascent against the electromagnets such as 76 under the effect of the stops 78, as shown in FIG. 4. At this stage of operation, two hypotheses are to be considered

First hypothesis: the weft thread to present now is the same as before. The electromagnet associated with the push rod 71B for controlling the same presentation finger 2B is excited and therefore keeps said push rod raised against its poles opposite the drawer, such as 56, for controlling the corresponding rocker 6B. The continued rotational movement of the cam 11 therefore brings the roller 17 closer to the axis of the shaft 12 and all the push rods advance simultaneously; only the push rod 71B pushes an upper drawer for active positioning of the finger 2B, while the other push rods, brought back to the low position by their return springs 77 in the absence of attraction from other electro -magnets, find nothing in front of them, the lower drawers such as 57 for placing inactive position of the other fingers than the finger 2B having already been advanced to the previous cycle. At the next passage of the bump of the cam 11 against the roller 17, all the push rods retreat, then go up at the end of the stroke, which has no effect on the drawers and the rocker arms, since the distal ends of the push rods s simply pull away from the drawers.

Second hypothesis: the weft wire to be presented is another wire than that which has just been presented by the finger 2B, for example that threaded into the eye of the finger 2. It is then the electromagnet 76, associated to the push rod 71, which is excited; it maintains this rod in the raised position (FIG. 4) while the continued rotational movement of the cam 11 causes all of the rods to advance. thrust. Only the rod 71, held in the high position by the electromagnet, will push the upper drawer 56 for placing the active position of the finger 2, while all the other push rods, lowered by their return springs 77 into the absence of excitation current in the corresponding electromagnets, advance at the level of the lower drawers such as 57 and, in particular, the push rod 71B meets the lower drawer for placing the rocker arm 6B in the inactive position which had just been set in active position at the previous frame insertion stroke; the other push rods in the low position meet nothing in front of them, since the corresponding lower drawers were already in the advanced position resulting from the inactive position of the corresponding rockers.

In general, it can be said that each rocker arm is brought into a positive position in a timely manner in the active position under the action of a push rod in the high position, and that it is also automatically and positively brought into position inactive, under the action of the same push rod in the low position. It can also be said that each rocker arm is returned to the inactive position when another rocker arm is placed in the active position, so that any presentation finger remains permanently in the active position as long as the wire frame it controls must be inserted successively several times.

• Si les tiges de poussée 71 ne sont pas dans leur position reculée représentée sur la figure 4, on commence par les y amener ; à cet effet, on commence par les y amener ; à cet effet, on saisit la manette 47 (figure 2) et on la tire dans le sens de la flèche f2, la douille 45 repousse le moyeu 47 appartenant aux moyens généraux de commande et s'engage, par sa rainure 46, sur la goupille 41. Dès lors, cette manette est solidaire en rotation de l'arbre 28. On appuie sur celui des leviers, tels que 81 ou 82 '(figure 1) qui correspond au doigt de présentation du fil de trame désiré, afin de soulever la tige de poussée, telle que 71, correspondante, puis on imprime à la manette un mouvement de rotation dans le sens de la flèche f4 (figure 1) pendant que son extrémité intérieure glisse dans la lumière fixe 52, afin de faire avancer l'axe transversal commun 34 emprisonné dans la manivelle 32 solidaire de l'arbre 28. La tige de poussée sélectionnée et maintenue en position haute repousse le tiroir supérieur de mise du culbuteur correspondant en position active, pendant que les autres tiges de poussée repoussent éventuellement le tiroir inférieur de remise en position inactive d'un culbuteur précédemment mis en position active. Enfin, on remet la commande manuelle au repos, c'est-à-dire que, d'une part, on relâche le levier tel que 81 et, d'autre part, on refait pivoter la manette 47 en sens inverse pour ramener l'arbre 28 dans sa position angulaire pour laquelle la goupille 41 peut retrouver sa place normale dans le moyeu 27 repoussé par le ressort 43 après qu'on a relâché complètement la manette 47. Le mécanisme mélangeur est alors de nouveau prêt à fonctionner en commande automatique.

The use of the manual selection control is as follows:

• If the push rods 71 are not in their retracted position shown in FIG. 4, we start by bringing them there; for this purpose, we start by bringing them there; for this purpose, the handle 47 is grasped (FIG. 2) and it is pulled in the direction of the arrow f2, the sleeve 45 pushes the hub 47 belonging to the general control means and engages, by its groove 46, on the pin 41. Therefore, this lever is integral in rotation with the shaft 28. It is pressed on that of the levers, such as 81 or 82 '(Figure 1) which corresponds to the presentation finger of the desired weft thread, in order to lift the push rod, such as 71, corresponding, then a rotary movement is imparted to the lever in the direction of the arrow f4 (FIG. 1) while its inner end slides in the fixed light 52, in order to advance the common transverse axis 34 trapped in the crank 32 integral with the shaft 28. The selected push rod and held in the high position pushes the upper drawer for setting the corresponding rocker arm in the active position, while the other push rods eventually push the drawer lower in. inactive sition of a rocker previously put in active position. Finally, the manual control is put back to rest, that is to say that, on the one hand, the lever is released as 81 and, on the other hand, the lever 47 is again pivoted in the opposite direction to bring back the shaft 28 in its angular position for which the pin 41 can return to its normal place in the hub 27 pushed back by the spring 43 after the lever 47 has been completely released. The mixing mechanism is then again ready to operate in automatic control .

Claims (7)

1. Weft yarn mixing device for weaving machines, comprising a support to be fixed on the machine and on which are mounted: a plurality of fingers for presenting the different weft yarns adapted to each take, selectively, ie an active active position presentation of a corresponding weft thread, ie a retracted inactive position; first individual positive control means for bringing each presentation finger to the advanced active position; second individual control means for returning each presentation finger to its retracted inactive position; general control means of the aforementioned first individual control means, adapted to be connected to the main shaft of the machine to operate in synchronism with said shaft; means for selective connection between the general control means and the first individual control means; and programmed selection control means suitable for controlling said selective connection means, characterized in that the second individual means for controlling the return of each presentation finger (2, 2B, 2C) to its retracted inactive position are also means positive control 157, 59) submitted also to the action of the selective connection means (71), and in that each presentation finger (2, 2B, 2C) is connected to a rocker arm (6, 6B, 6C) subjected to the antagonistic actions programmed by the first and second individual control means (56, 58 and 57, 59). 2. Device according to claim 1, characterized in that each rocker arm (6) is connected to a drawer (56) for positioning the active position of a presentation finger and to a drawer (57) for positioning the inactive position of the same finger; and in that the selective connection means comprise a plurality of push rods (71) equal in number to that of the rocker arms, the proximal end of which is articulated on a drive axis (34) animated by a transverse movement of back and forth by the general control means (11, 18, 24, 26, 28, 32, 34) and the distal end of which is, selectively, either in the active position opposite the drawer for placing in the active position corresponding, either in the inactive position opposite the corresponding inactive positioning slide, depending on whether the push rod in question is stressed, or not, by the selection control means (76). 3. Device according to claim 2, characterized in that the selection control means are constituted by a plurality of individual electromagnets (76) in number equal to that of the push rods (71) located in the immediate vicinity of the rods respective thrust and adapted to attract them selectively to temporarily keep them in the active position. 4. Device according to claim 3, characterized in that each push rod (71) is biased by a spring (77) towards its position inactive. 5. Device according to claim 3, characterized in that each push rod (71) is provided with a cam (78) which cooperates with a fixed stop (79) integral with the support (1); the locations of the cam on the push rod and of the stop on the support as well as the configuration and the dimensions of said cam being such that, only when the rod reaches the end of its recoil stroke under the action of general means control, it is pushed back positively under the effect of said cam against the corresponding selection electromagnet. 6. Device according to claim 1, characterized in that it comprises means (27, 41) for disengaging the general control means (28, 32, 34), as well as means (41, 45, 46, 47) manual control of the aforementioned selective connection means (71) and manual selection control means (81, 82). 7. Device according to claims 2 and 6, characterized in that the manual control means of the selective connection means comprise a lever (47) for actuating the axis (28) for driving the push rods, and in that the manual selection control means comprise individual levers (81, 82) for selectively placing said push rods (71) in the active position.

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