FR2873131A1 - Jacquard loom shed forming mechanism with two electromagnets and mobile hooks has hook bodies that press against cutter and flexible vanes - Google Patents

Abstract

The shed forming mechanism for a three-position Jacquard loom has two selectively-activated electromagnets (4, 5) located one above the other, retaining levers (21, 21', 22, 22'), pairs of hooks (11, 12, 11', 12') and a mobile cutter (13'). In each pair of hooks a first hook (11, 11') has a body (111) designed to apply a simple pressure against the cutter and a flexible metal or plastic vane (113, 113') that is designed to interact with a retaining lever (21, 21'). The second hook (12, 12') in each pair has a body (121) designed to apply a simple pressure against the first hook's body and a flexible vane (123, 123') that interacts with the other retaining lever (22, 22'). Each vane is fixed to the corresponding body with a possible clearance (F3) between the two.

Description

2873131 1

  The invention relates to a shedding mechanism, a three-position weave mechanism and a weaving loom equipped with such weave mechanics.

  A loom incorporating a clean armor mechanism to generate three positions warp son is generally used for the realization of special fabrics such as, especially, velvet or carpets.

  EP-A-0 839 937 discloses a three-position weave mechanism in which movable hooks are provided to be moved in pairs by the knives of the machine, one hook of each pair being in simple bearing on the second hook of this pair. The hooks are joined in pairs by funicular elements and associated with several pulleys adapted to be spaced apart from one another in a variable manner, depending on the position of these four hooks.

  It is also known from EP-A-0 899 367 to provide, in a selection device for a three-position armor mechanic, two pairs of pivoting levers, arranged on either side of two superposed electromagnets, the levers of each pair of levers that can be controlled by one of the electromagnets and each provided with a movable hook immobilizing nose belonging to a pair of hooks superimposed on one another and able to be moved together by a knife.

  This device works properly but is relatively complex in manufacturing in that one of the pivoting levers extends on both sides of its axis of articulation with an elaborate form, which increases all its cost price. . In addition, wad can accumulate in the area provided between each lever and the adjacent portion of the electromagnet which serves to control its pivoting which can, in the long run, lead to selection errors that lead to the creation of faults on the fabric or carpet being manufactured.

  In this known device, the two movable hooks penetrate near the top dead center of their trajectory, between the spouts of the retaining levers, these movable hooks being in practice made of plastic and having a variable width according to the manufacturing tolerances, differences in width of the movable hooks may lead to improper positioning of one or other of the pivoting retaining levers, which again may lead to mistakes on the fabric or carpet being woven.

  It is these drawbacks that the invention intends to remedy more particularly by proposing a shedding mechanism intended to be used in a three-position armormechanical and whose manufacture and use are easier than those systems of the state of the art, while its reliability of operation is improved.

  In this spirit, the invention relates to a shedding mechanism for the three-position weave mechanism of a jacquard weaving loom, said mechanism comprising at least two electromagnets superimposed and able to be selectively activated, and two pairs of pivoting retaining levers, the retaining levers of the same pair being disposed on the same side of the electromagnets and each provided with a metal armature adapted to cooperate with one of the electromagnets and a spout for retaining a movable hook belonging to a pair of hooks adapted to be moved together by a knife. This mechanism is characterized in that, within the same pair of movable hooks, a first hook comprises a body intended to come into simple support on the knife and a flexible blade intended to interact with one of the retaining levers, while the second hook comprises a body intended to come into simple support on the body of the first hook, and a flexible blade intended to interact with the other lever of the same pair of levers, in that each blade is fixed on the corresponding body with the possibility of movement, in that the retaining lip of each retaining lever is formed on the opposite side of the lever to the associated electromagnet, in that the levers of levers levers one pair are offset relative to each other both in a direction parallel to the direction of movement of the associated movable hooks and in a direction perpendicular to this direction of movement and in that the portions of the flexible blades intended to interact with these retention spouts have substantially the same offset between them in the two aforementioned directions when the body of the second movable hook bears on the body of the first.

  Thanks to the invention, the flexible blade attached to the body of each movable hook is intended to interact with one of the levers of a pair of levers, its geometry being well defined because the manufacturing tolerances of a blade can be very precise. On the other hand, the body of each hook, which is advantageously made of synthetic material, can be very solid because relatively mass. The flexibility of the blade is used to allow its movement relative to the body of each hook, which allows it to come into effective engagement with the corresponding retaining lever, either when leveling the pivoting levers or for the retaining the hook in the vicinity of the upper position of its trajectory. As the immobilization beaks of the two levers of the same pair are oriented in the same direction, the leveling force exerted by the elastic blade on the levers is quite comparable between the two levers and, at the Inversely, the retaining force exerted by the spout of each lever is quite comparable on the two hooks of the same pair. In addition, the electromagnets, their respective control devices and the associated levers may be substantially identical, which facilitates the development of the trade, improves reliability, reduces the cost and makes the mechanism more compact. This is important since an armor mechanic can have more than 10,000 such mechanisms.

  According to advantageous but non-obligatory aspects of the invention, such a mechanism can incorporate one or more of the following characteristics, taken in any technically possible combination: the blades of the same pair of hooks are able to bear against the levers on the side of their respective retention spouts and to press these levers towards the electromagnets, during a leveling operation.

  - Each retaining lever is articulated about a fixed axis relative to a housing of the mechanism and extends, relative to this axis, substantially in a direction perpendicular to this axis and one side thereof. The retaining levers are thus more compact and more robust than the upper levers of EP-A-0 899 367.

  The two retaining levers of the same pair are substantially identical, which makes it possible to save manufacturing costs and facilitates the management of the stock of spare parts.

  - Each retaining lever is provided with at least one baffle adapted to isolate from the outside a variable volume chamber according to its angular position. This avoids the accumulation of fluff in such a chamber and limits the risk of malfunction.

  - The body of the first hook is provided, on a first side, a spout adapted to come into simple support on the corresponding knife and, on a second side opposite to the first side, a heel adapted to receive in simple support a part of the body of the second hook. The transmission of force between the first and the second hook of a pair thus takes place without stressing the flexible blades carried by each of these bodies, the mechanical characteristics of these blades being able to be optimized according to their respective functions of leveling and / or hooking the hooks on the retaining levers. In this case, the beak and the heel of the body of the first hook advantageously extend on either side of the flexible blade fixed on this body.

  - The flexible blades of the movable hooks of the same pair are of different lengths and guided, so that they can bend under similar conditions, which allows to apply substantially the same effort on the levers associated during leveling.

  The invention also relates to a three-position Jacquard loom weave mechanism which comprises at least one selection mechanism as previously described. Such a mechanism is more reliable and more economical than those of the state of the art.

  Finally, the invention relates to a loom equipped with a weave mechanism as mentioned above, such a loom being more reliable and easier to use than those of the state of the art.

  The invention will be better understood and other advantages thereof will appear more clearly in the light of the following description of an embodiment of a loom, armor mechanics and a selection mechanism in accordance with its principle, given solely by way of example and with reference to the accompanying drawings in which: - Figure 1 is a longitudinal sectional view of part of a mechanism for forming the crowd according to the invention in a first configuration; - Figure 1A is a detailed view of the interaction zone between a movable hook and a retaining lever, on a larger scale and in the direction of the arrow A in Figure 1; FIG. 2 is a half-section corresponding to the right-hand part of FIG. 1, while the mechanism is in a second configuration, and FIG. 3 is a half-section similar to FIG. 2, while the mechanism is in a third configuration.

  The shedding mechanism shown in Figures 1 to 3 is intended to be integrated with a three-position weave mechanism mounted on a carpet-making loom. It allows to control the position of a carabiner or bottom end hook of an arch to which is or are suspended one or more smooth. The part of the mechanism shown in the figures is associated with several superimposed pulleys according to the teaching of EP-A-0 839 937, the relative position of the pulleys for controlling the height of the aforementioned carabiner or end hook. To control the position of these pulleys, two of which are shown schematically only in FIG. 1 with the references P1 and P2, two funicular elements 1 and 2 made in the form of cords respectively connect two outer movable hooks 11 and 11 'and two movable hooks. 12 and 12 '. The hooks 11 and 12, on the one hand, and 11 'and 12', on the other hand, are intended to be moved together by a knife 13 or 13 ', the inner hook of each pair of hook being then in position. simple support on the outer hook of the same pair, this also in accordance with the technical teaching of EP-0 839 937.

  The mechanism M also comprises two electromagnets 4 and 5 superimposed parallel to the direction of a substantially vertical axis Z-Z 'in FIG. 1 and corresponding to the direction of movement of the pulleys P1 and P2. The electromagnets 4 and 5 can be selectively activated by a not shown control module.

  On either side of the electromagnets 4 and 5 are arranged two pairs of levers 21 and 21 ', respectively 22 and 22'. The levers 21, 21 ', 22 and 22' are structurally identical and are each pivotally mounted about a shaft 211, 211 ', 221 respectively 221' whose geometric axis X211, X211 ', X221, X221, is fixed by compared to a housing 6 of the immobilized mechanism with respect to the structure of the craft. The X211 and equivalent axes are generally perpendicular to the ZZ 'axis. The lever 21 comprises an upper eyelet 212 in which is formed a passage opening of the shaft 211 and extends, essentially, below the shaft 211 in Figure 1, that is to say in practice downwards in a direction generally parallel to the axis ZZ '. The lever 21 comprises a metal armature 213 disposed substantially facing the electromagnet 4 and which extends in a direction generally parallel to the axis ZZ 'and perpendicular to the axis X211. The lever 21 is provided with a spout 214 on which can be hung a portion of the movable hook 11, as can be seen from the explanations that follow.

  The lever 21 also carries a deflector 215 which makes it possible to isolate from the outside a chamber C21 of variable volume as a function of the angular position of the lever 21 around the X211 axis. Indeed, the lever 21 is pivotally mounted about the axis X2111 as it emerges from the double arrow F1, the chamber C21 being bordered by the two polar contact surfaces respectively provided on the lever 21 and on the electromagnet 4 The angular position of the lever 21 can be controlled by means of the electromagnet 4 and a compression spring 14 which is interposed between the lever 21 and a central portion 6A of the housing 6. The spring 14 exerts on the lever 21 a elastic force E4 which tends to move the spout 214 of the axis Z-Z '.

  The levers 21 ', 22 and 22' are structurally identical to the lever 21 and are each provided with a metal frame 213 ', 223 and 223', a retaining lip 214 ', 224 and 224' and a deflector 215 ', 225 and 225' and subjected to the action of a spring 14 ', 15 and 15'.

  The levers 21 ', 22 and 22' also each extend in a direction generally parallel to the axis Z-Z 'with respect to the axes X211', X221 and X221 '. These levers are pivotally mounted about their respective axes, as shown by the arrows F'1, F2 and F'2 and their position can be controlled by the electromagnets 4 or 5 and the springs 14 and the like.

  The axes X211 and X221 are offset parallel to the axis ZZ 'by a distance d1 greater than the length of the lever 21. These axes are also offset in a direction YY' perpendicular to the axis ZZ 'and to the axes X211 and X221, a distance d2, the axis X211 being further from the axis ZZ 'than the axis X221. As the levers 21 and 22 are identical, the beaks 214 and 224 are also offset distances d1 and d2 both parallel to the axis ZZ 'and perpendicular to this axis.

  The fact that the retaining levers extend on one side of their respective axes of articulation makes it possible to obtain a good definition of their geometry quite easily, which significantly conditions the operating reliability of the mechanism M In particular, the inertia in rotation of these levers is relatively low, which makes it possible to use return springs 14 and the like, exerting a low E4 return force or equivalent of intensity and, consequently, electromagnets 4 and 5 are relatively weak and therefore compact.

  The hook 11 is bi-partite and comprises a body 111 of relatively massive plastic material and in which is molded an end 112 of a flexible metal blade 113 intended to interact with the lever 21. This bi-partite structure can be approximated by that described in EP-A-1 413 657 for a two-position armor mechanic. However, the mechanism of the present invention is substantially different from this prior art because of its particular configuration adapted to a three-position armor mechanic.

  The blade 113 is provided, in the vicinity of its end 114 furthest from the body 111, from an opening for receiving the spout 214 of the lever 21. Thus, as shown on the right of FIG. be held in position, near the top dead center of its trajectory, by the lever 21.

  In the same way, the hook 12 comprises a body 121 of synthetic material in which is molded the lower end 122 of a flexible metal blade 123 intended to interact on the lever 22. In the vicinity of its upper end 124, the blade is provided with an opening for receiving the spout 224 of the lever 22.

  Note that the blade 113 is substantially longer than the blade 123, which corresponds to the fact that, in the position of retaining the movable hooks 11 and 12 to the 2873131 10 near the top dead center of their trajectory, the distance between the body 111 and the spout 214 is substantially greater than the distance between the body 121 and the spout 224.

  Given their flexibility, the blades 113 and 123 are capable of angular displacement relative to their attachment zone on the bodies 111 and 121, which represent the arrows F3.

  The blades 113 and 123 are each guided in a slideway 116 or 126 formed by the housing 6 and extending to the vicinity of the lever 21 or 22. At the same distance d6 from the hooks 214 and 224, the slides 116 and 126 flare, away from the axis ZZ 'and up to the beaks, to allow the bending of the blades 113 and 123 on the same height, in the vicinity of their respective upper ends 114 and 124. Thus, even if the blades 113 and 123 have different lengths, they flex under similar conditions, which implies that the leveling forces exerted on the levers 21 and 22 are substantially identical.

  When the hook 12 bears on the hook 11, the ends 114 and 124 of the blades 113 and 123 and, in particular, their openings 115 and equivalent, have the same spatial offset as the nozzles 214 and 224. In other words , the ends 214 and 224 are offset by dl parallel to ZZ 'and d2 parallel to Y-Y', which allows them to interact simultaneously with the hooks 214 and 224.

  The structure of the movable hooks 11 'and 12' is respectively identical to that of the hooks 11 and 12.

  Note that the spouts 214 and 224 are directed, relative to the main part of the levers 21 and 22, opposite the magnets 4 and 5. In the same way, the spouts 214 'and 224' are directed to the opposite electromagnets.

  Thus, the blades 113, 123, as well as the corresponding blades 113 'and 123' of the movable hooks 11 'and 12', come into contact with the levers 21, 22, 21 'and 22' from the outside. -vis electromagnets 4 and 5, which is particularly advantageous when leveling the retaining levers, that is to say in the position shown on the left of Figure 1 when the knife 13 'moves the hook 11', so that the upper ends 114 'and 124' of the blades 113 'and 123' push the levers 21 'and 22' towards the electromagnets 4 and 5. If either of the electromagnets 4 or 5 is then activated by the control module, or levers 21 'and 22' is or are effectively retained (s) substantially pressed against the electromagnet (s), which allows the hook 11 'and possibly the hook 12' to descend down on the knife 13 'when it begins its downward stroke.

  Such a configuration is shown on the right of Figure 2 and corresponds to the descent of the knife 13 after a leveling has been performed as shown on the left of Figure 1. In this case, the electromagnet 4 was activated then that the electromagnet 5 has not been activated, so that the spout 224 of the lever 22 which is pushed by the spring 15 has retained in position the blade 123 and, consequently, the whole of the hook 12, whereas, in view of the activation of the electromagnet 4, the spout 214 of the lever 21 has been removed from the path of the blade 113, which allows the hook 11 to come down on the knife 13.

  Like the blades 113 and 123, the blades 113 'and 123' are guided in guides ensuring equal leveling efforts exerted on the levers 21 'and 22'.

  In the configuration of FIG. 3, the electromagnets 4 and 5 have been activated, so that the nozzles 214 and 224 of the levers 21 and 22 have been erased from the down paths of the blades 113 and 123 after leveling. In this case, the hooks 11 and 12 descend with the knife 13, resting on it.

  The body 111 comprises a spout 111A intended to rest on the knife 13 during movements of the hook 11 and a heel 111B located on the side of the body 111 opposite the spout 111A relative to the blade 113, this heel 111B is intended to receive in simple support a heel 121B formed by the body 121, in particular in the configurations of Figures 1 and 3. Thus, the interaction between the body 111 and 121 of the hooks 11 and 12 does not affect the part of these hooks used for their retention in the high position, whereas this is the case of materials known from EP-AO 839 937 and EP-A-0 899 367.

  A weave mechanism according to the invention incorporates several mechanisms such as that described above and shown in the figures, in practice such a mechanism by smooth or group of smooth whose position must be controlled.

  A loom according to the invention and provided with such armor mechanics as mentioned above can be used for weaving special fabrics, including velvet or carpets. It is more economical to buy and operate and the risk of mistakes is reduced.

  The invention has been shown with two electromagnets 4 and 5 arranged between the levers 21, 21 ', 22 and 22'. It also applies to the case where the electromagnets are four in number, an electromagnet being dedicated to each lever.

  In addition, the blades 113, 113 ', 123 and 123' are not necessarily metallic. They can be made of a synthetic material having mechanical properties adapted to their function, for example carbon fibers or plastics material filled with reinforcing fibers.

Claims (1)

  A shedding mechanism for a Jacquard-type three-position weave armor mechanism, said mechanism comprising at least two superposed and selectively energized electromagnets, and two pairs of pivoting retaining levers, the retaining levers of the same pair being disposed on the same side of said electromagnets and each provided with a metal armature adapted to cooperate with one of said electromagnets and a spout for retaining a movable hook belonging to a pair of hooks adapted to be moved jointly by a knife, characterized in that within a same pair of movable hooks (11, 12, 11 ', 12'), a first hook (11, 11 ') comprises a body (111) intended to come into simple abutment on said knife (13, 13 ') and a flexible blade (113, 113') intended to interact with a retaining lever (21, 21 '), while the second hook (12, 12 ') comprises a body (121) destined to come in simple support on the body of said first hook and a flexible blade (123, 123 ') for interacting with the other lever (22, 22') for retaining the same pair of levers, in that each blade is fixed to the corresponding body with the possibility of deflection (F3), in that the retaining nose (214, 214 ', 224, 224') of each retaining lever (21, 21 ', 22, 22') is arranged on the side of said lever opposite to the associated electromagnet (4, 5), in that the levers of the levers of the same pair of levers are offset (d1, d2) relative to each other to both in a direction (Z-Z ') parallel to the direction of movement of the associated movable hooks and in a direction (Y-Y') perpendicular to said direction of movement and in that the portions (114, 115, 124) flexible blades (113, 123, 113 ', 123') for interacting with said retainers have substantially the same offset (d1, d2) therebetween said directions, when the body of the second mobile hook (12, 12 ') bears on the body of the first movable hook (11, 11').   2. Mechanism according to claim 1, characterized in that said blades (113, 123, 113 ', 123') of the same pair of hooks (11, 12, 11 ', 12') are able to bear against said retaining levers (21, 21 ', 22, 22') on the side of their respective retaining tips (214, 214 ', 224, 224') and pressing said levers towards said electromagnets.   3. Mechanism according to one of the preceding claims, characterized in that each retaining lever (21, 21 ', 22, 22') is articulated about an axis (X21, X21, X22, X22-) fixed relative to a housing (6) of said mechanism (M) and extends, with respect to said axis, substantially in a direction (Z-Z ') perpendicular to said axis and only one side thereof.   4. Mechanism according to one of the claims   previous, characterized in that the two retaining levers (21, 22; 21 ', 22') of the same pair are substantially identical.   5. Mechanism according to one of the claims   previous, characterized in that each retaining lever (21, 21 ', 22, 22') is provided with at least one deflector (215, 215 ', 225, 225') adapted to isolate a chamber from the outside ( C21) of variable volume according to the angular position (F1, F'1, F2, F'2) of said lever.   6. Mechanism according to one of the preceding claims, characterized in that the body (111) of said first hook (11, 11 ') is provided on a first side, a spout (111A) adapted to come in simple support on said knife (13, 13 ') and, on a second side opposite the first side, of a heel (111B) adapted to receive in single support a portion (121B) of the body (121) of the second hook (12). , 12 '). 7. Mechanism according to claim 6, characterized in that said spout (111A) and said heel (111B) of the body (111) of said first hook (11, 11 ') extend on either side of the flexible blade (113, 113 ') attached to said body.   8. Mechanism according to one of the preceding claims, characterized in that the flexible blades (113, 123, 113 ', 123') of the movable hooks (11, 12, 11 ', 12') of the same pair of hooks have different lengths and are guided (116, 126) so that (d6) they can flex (F3) under similar conditions.   9. Three-position Jacquard loom mechanism comprising at least one selection mechanism (M) according to one of the preceding claims.   Jacquard loom equipped with a weave mechanism according to claim 9.