EP3719187B1 - Device for forming a shed and jacquard loom equipped with such a device - Google Patents

Description

The present invention relates to a shed-forming device for a Jacquard-type loom.

In the field of looms of the Jacquard type, it is known to use a device for forming the shed, sometimes called "mechanical Jacquard" comprising two series of blades or longitudinal knives driven by an alternating vertical movement in phase opposition , on which the hooks of collar movement selection devices constituting the upper ends of a Jacquard harness can come to rest.

CN-U-201915195 discloses such a Jacquard mechanism which comprises two oscillating axes arranged one above the other and articulated in two plates, between which extend two series of knives or blades as well as the two axes. The two axes are equipped with tilting levers on each of which is articulated a connecting rod which supports a drive bar for a series of blades, such a bar sometimes being referred to as an “oblique bar”. An input shaft drives the two oscillating axes by means of two eccentrics which each actuate a control rod connected to a crank fixed to one of the oscillating axes.

Such kinematics has the advantage of simplicity. However, it lacks rigidity to be able to ensure correct operation at the high speeds required in modern weaving workshops, in particular greater than 1000 picks/minute. Indeed, the oscillating axes which are each connected to a crank are subjected to high torques which induce deformations likely to slow down, or even block, the operation of the Jacquard mechanism. Besides CN105483895 shows another shedding device for a Jacquard-type loom, having overlapping oscillating shafts. However, said device lacks control rods, as described in CN-U-201915195 .

It is these drawbacks that the invention more particularly intends to remedy by proposing a new device for forming the shed for a loom of the Jacquard type which has a simple structure and which can operate reliably at high speeds.

• deux séries de couteaux longitudinaux s'étendant parallèlement à un axe longitudinal du dispositif de formation de la foule, animés d'un mouvement vertical alternatif en opposition de phase et reliés, à chacune de leurs extrémités, à une barre d'entraînement ;
• un arbre oscillant supérieur et un arbre oscillant inférieur qui s'étendent l'un au-dessus de l'autre et qui sont respectivement pourvus, à chacune de leurs extrémités, de deux leviers basculants reliés chacun à une barre d'entraînement par une bielle de liaison ;
• deux platines de châssis, entre lesquelles s'étendent les deux séries de couteaux et les arbres oscillants et qui sont pourvues de paliers d'articulation des arbres oscillants ;
• un arbre d'entrée animé d'un mouvement de rotation continue et équipé d'un premier excentrique et d'un deuxième excentrique disposés au voisinage d'une première platine, parmi les deux platines de châssis, à l'extérieur d'un volume défini entre ces platines, le premier excentrique entraînant une première bielle de commande attelée à une première manivelle appartenant à un premier arbre oscillant, parmi les deux arbres oscillants, le deuxième excentrique entraînant une deuxième bielle de commande attelée à une deuxième manivelle appartenant au deuxième arbre oscillant, parmi les deux arbres oscillants, et la première bielle de commande étant plus éloignée de la première platine, le long de l'axe longitudinal, que la deuxième bielle de commande.

To this end, the invention relates to a device for forming the shed for a Jacquard-type loom, comprising:

• two series of longitudinal knives extending parallel to a longitudinal axis of the shedding device, driven by a movement alternating vertical in phase opposition and connected, at each of their ends, to a drive bar;
• an upper rocking shaft and a lower rocking shaft which extend one above the other and which are respectively provided, at each of their ends, with two rocking levers each connected to a drive bar by a connecting rod link ;
• two chassis plates, between which extend the two series of knives and the oscillating shafts and which are provided with hinge bearings of the oscillating shafts;
• an input shaft driven in a continuous rotation movement and equipped with a first eccentric and a second eccentric arranged in the vicinity of a first plate, among the two chassis plates, outside a volume defined between these plates, the first eccentric driving a first control rod coupled to a first crank belonging to a first oscillating shaft, among the two oscillating shafts, the second eccentric driving a second control rod coupled to a second crank belonging to the second shaft oscillating, among the two oscillating shafts, and the first control rod being farther from the first plate, along the longitudinal axis, than the second control rod.

According to the invention, the two eccentrics, the two control rods and the two cranks are contained in a casing which supports at least one additional hinge bearing of the first oscillating shaft.

Thanks to the invention, the first oscillating shaft, which has the greatest length beyond the first plate with respect to the volume defined between the two plates, because it is connected to the first connecting rod which is the most remote from this first plate, does not extend cantilevered but between the bearings supported respectively by the first plate and by the casing. This limits the risks of deformation of this first oscillating shaft during operation of the Jacquard mechanism and allows it to work reliably at high speeds.

• Le carter supporte, en outre, un palier d'articulation supplémentaire du deuxième arbre oscillant.
• Le premier arbre oscillant est l'arbre oscillant inférieur.
• En variante, le premier arbre oscillant est l'arbre oscillant supérieur.
• Chaque arbre oscillant comprend un tube creux fixé, à chacune de ses extrémités, sur une bascule qui inclut deux leviers basculants et chaque bascule est articulée dans un palier de l'une des platines de châssis.
• Le diamètre du tube creux d'un arbre oscillant est compris entre 80 et 160 mm, de préférence entre 100 et 140 mm, de préférence encore de l'ordre de 120 mm.
• La première manivelle est fixée sur une bascule du premier arbre oscillant et articulée dans le palier supporté par le carter.
• Chaque palier d'articulation supporté par le carter est équipé d'un roulement dans lequel est introduite une partie de l'un des arbres oscillants.
• Chaque palier d'articulation supporté par le carter est formé par un chapeau ajustable radialement par rapport à l'axe de l'arbre oscillant, monté dans un logement d'une paroi du carter et serré sur la paroi du carter.

According to advantageous but non-mandatory aspects of the invention, such a crowd-forming device may incorporate one or more of the following characteristics, taken in any technically permissible combination:

• The casing also supports an additional hinge bearing of the second oscillating shaft.
• The first swingshaft is the lower swingshaft.
• Alternatively, the first oscillating shaft is the upper oscillating shaft.
• Each oscillating shaft comprises a hollow tube fixed, at each of its ends, to a rocker which includes two rocking levers and each rocker is hinged in a bearing of one of the chassis plates.
• The diameter of the hollow tube of an oscillating shaft is between 80 and 160 mm, preferably between 100 and 140 mm, more preferably around 120 mm.
• The first crank is fixed on a rocker of the first oscillating shaft and hinged in the bearing supported by the casing.
• Each hinge bearing supported by the casing is fitted with a bearing into which a part of one of the oscillating shafts is inserted.
• Each articulation bearing supported by the casing is formed by a cap that can be adjusted radially with respect to the axis of the oscillating shaft, mounted in a housing in a wall of the casing and tightened on the wall of the casing.

According to another aspect, the invention relates to a loom of the Jacquard type which comprises, among other things, a device for forming the shed as mentioned above.

Such a loom can operate reliably at high speed without being limited by the shedding device.

• [Fig 1] la figure 1 est une vue en perspective d'un métier à tisser conforme à l'invention incorporant un dispositif de formation de la foule conforme à l'invention ;
• [Fig 2] la figure 2 est une vue en perspective, selon un autre angle, du dispositif de formation de la foule conforme à l'invention représenté à la figure 1, certaines parties de ce dispositif étant omises pour la clarté du dessin ;
• [Fig 3] la figure 3 est une vue d'extrémité du dispositif de formation de la foule de la figure 2 dans laquelle une platine omise à la figure 2 est représentée, mais pas un carter omis à la figure 2 ;
• [Fig 4] la figure 4 est une coupe partielle selon la ligne IV-IV à la figure 3, le carter étant en place, et
• [Fig 5] la figure 5 est une coupe partielle analogue à la figure 4 pour un dispositif de formation de la foule conforme à un deuxième mode de réalisation de l'invention.

The invention will be better understood and other advantages thereof will appear more clearly in the light of the following description of two embodiments of a shedding device and a weaving loom principle, given solely by way of example and made with reference to the accompanying drawings, in which:

• [ Fig 1 ] there figure 1 is a perspective view of a loom according to the invention incorporating a shedding device according to the invention;
• [ Fig 2 ] there figure 2 is a perspective view, from another angle, of the shedding device according to the invention shown in figure 1 , certain parts of this device being omitted for clarity of the drawing;
• [ Fig.3 ] there picture 3 is an end view of the shedding device of the figure 2 in which a plate omitted at the figure 2 is shown, but not a crankcase omitted from the figure 2 ;
• [ Fig 4 ] there figure 4 is a partial section along line IV-IV at the picture 3 , the housing being in place, and
• [ Fig.5 ] there figure 5 is a partial cut analogous to figure 4 for a shedding device according to a second embodiment of the invention.

The loom M represented very schematically in figure 1 is of the Jacquard loom type and comprises a shedding device, 2, also called "Jacquard mechanics", intended to move alternately, with a vertical movement represented by the double arrow F1 at the figure 1 , heddles 4 provided with eyelets 42 for passing warp threads 6.

The various healds are supported by the cords of a Jacquard harness 8 whose upper ends are connected to the collars of selection devices provided with hooks 10 resting on two series of knives 12 and 14 animated by an alternating vertical movement in opposition to phase represented by the double arrow F2 at the figure 1 . The two series of knives 12 and 14 are nested one inside the other, in the sense that, except at the level of the longitudinal edges of the device for forming the shed 2, a knife 12 is arranged between two knives 14 and vice versa.

The shedding device 2 comprises a frame 16 which includes two longitudinal crosspieces 18 and 20 extending parallel to a longitudinal axis X2 of the shedding device 2. For clarity of the drawing, the longitudinal crosspiece 20 is omitted. to the figure 1 , while the longitudinal crosspiece 18 is omitted at the figure 2 .

The two series of knives 12 and 14 extend between the longitudinal crosspieces 18 and 20, parallel to the axis X2.

The chassis 16 also comprises a first chassis plate 22 and a second chassis plate 24 arranged between the longitudinal crosspieces 18 and 20 and which each extend perpendicularly to the axis X2. The two series of knives 12 and 14 are arranged along the axis X2, in a volume V2 of the shed forming device 2 located between the plates 22 and 24.

Each chassis plate 22 or 24 is produced by molding and machining metal, preferably cast iron, and comprises stiffening ribs, some of which are visible on the figure 1 And 2 with the reference 241 for the plate 24, the stiffening ribs of the plate 22 being hidden from the figure 1 . For the clarity of the drawing, the plate 22 is omitted at the figure 2 .

Each knife 12 or 14 of a series of knives is linearly guided in its vertical movement according to the double arrow F2 and connected, at each of its ends, to a rod 26 suspended from a drive bar, also called "oblique bar" . More precisely, each knife of a series of knives 12 or 14 is suspended by two connecting rods 26 from two drive bars, namely a first drive bar arranged in the vicinity of the plate 22 and a second drive bar arranged in the vicinity of plate 24.

The four training bars are visible at the figure 2 and comprise a first drive bar 30 and a second drive bar 32 disposed adjacent the platen 22, as well as a third drive bar 34 and a fourth drive bar 36 disposed adjacent the platen 24 The four drive bars 30 to 36 are respectively each articulated on a guide arm 31, 33, 35 or 37, itself articulated on the frame 16, at or near the longitudinal crosspiece 18.

Each drive bar is made up of two flanges, like the drive bar 30 of which the flanges are noted 302 and 304.

The shedding device 2 also comprises an upper oscillating shaft 40 and a lower oscillating shaft 42 arranged one above the other and which extend parallel to the axis X2.

The upper oscillating shaft 40 comprises a tube 402 whose diameter is, in the example, equal to 120 mm. In practice, the diameter of the tube 402 is between 80 and 160 mm, preferably between 100 and 140 mm, more preferably around 120 mm, which gives it good torsional rigidity.

At each of its ends, the tube 402 is fixed to a rocker 404 which also belongs to the shaft 40 and which defines two rocking levers 405 and 406.

Similarly, the lower oscillating shaft 42 includes a central tube 422 and two rockers 424 which each define two rocker levers 425 and 426. The diameter of the tube 422 is the same as that of the tube 402.

We note respectively X40 and X42 the longitudinal axes of the oscillating shafts 40 and 42. These axes are parallel to the longitudinal axis X2.

Latches 404 and 424 are respectively secured to tubes 402 and 422 by screws 43 parallel to axes X40 and X42.

Near the plate 22, the tilting levers 405 and 406 of the rocker 404 are respectively connected to the drive bar 30 and to the drive bar 32 by means of connecting rods 50. In the same way, at the vicinity of the plate 24, the tilting levers 405 and 406 of the rocker 404 are respectively connected by connecting rods 50 to the drive bar 34 and to the drive bar 36.

Near the plate 22, the tilting levers 425 and 426 of the rocker 424 are respectively connected to the drive bar 30 and to the drive bar 32 by means of connecting rods 52. Similarly, in the vicinity of the plate 24, the tilting levers 425 and 426 of the rocker 424 are respectively connected by connecting rods 52 to the drive bar 34 and to the drive bar 36.

The position of the points of articulation of the connecting rods 50 and 52 on the tilting levers 405, 406, 425 and 426 is adjustable, in notches in the form of an arc of a circle provided on these tilting levers.

Bearings are respectively provided in the plates 22 and 24 to support the oscillating shafts 40 and 42 in their alternating rotational movement around their axes X40 and X42. Thus, the plates 22 and 24 constitute support plates for the oscillating shafts 40 and 42.

More specifically, bearings 220 and 240 are respectively provided in plates 22 and 24 to support upper oscillating shaft 40. Bearing 220 is through, whereas bearing 240 is blind. In practice, each of the bearings 220 and 240 is equipped with a bearing 620, respectively 640. The parts of the shaft 40 engaged in the bearings 620 and 640 are axial ends 404A of the rockers 404 opposite the tube 402. Latches 404 of shaft 40 are articulated in plates 22 and 24.

In the same way, the plates 22 and 24 carry two bearings 222 and 242 in which the rockers 424 of the lower oscillating shaft 42 are articulated, with the interposition of two bearings 622 and 642. The bearing 222 is through, whereas the bearing 242 is blind. Here again, it is the axial ends 424A of the rockers 424A opposite the tube 422 which are hinged in the bearings 622 and 642.

Bearings 620, 622, 640 and 642 are needle roller bearings. Alternatively, they could be ball bearings or any other type of bearing.

The two oscillating shafts 40 and 42 are driven in rotation, respectively around the axes X40 and X42 by a drive assembly 70 arranged on the side of the plate 22 opposite the knives 12 and 14, that is to say the outside of volume V2. The movement or the control of the oscillating shafts 40 and 42 thus comes from the side of the plate 22 which can be described as a “control plate”.

The drive assembly 70 comprises an input shaft 72 driven by a continuous rotational movement represented by the arrow F3 as well as a first eccentric 74 and a second eccentric 76. Along the axis X2, the second eccentric 76 is located closer to plate 22 than first eccentric 74.

The first eccentric 74 drives a first control rod 84 which is coupled to a first crank 428 which forms part of the oscillating shaft 42 and which is mounted at the end of the rocker 424 articulated in the bearing 222. The second eccentric 76 drives a second control rod 86 coupled to another crank 408 which belongs to the upper oscillating shaft 40 and which is mounted at the end of the rocker 404 articulated in the bearing 220.

The cranks 408 and 428 are respectively mounted on the rockers 404 and 424 which pass through the plate 22, on the side of these rockers opposite the tubes 402 and 422. Screws 45, parallel to the axes X40 and X42, are used to secure together the parts 404 and 408 of rocker shaft 40 and parts 424 and 428 of rocker shaft 42.

The first control rod 84 is further away, along the axis X2, from the plate 22 than the second control rod 86. Thus, with respect to the control plate 22, the second eccentric 76 and the second connecting rod 86 can be qualified as proximal eccentric and proximal connecting rod, whereas the first eccentric 74 and the second connecting rod 84 can be qualified as distal eccentric and distal connecting rod.

A casing 90 is mounted on the plate 22, on the side of this plate opposite the tubes 402 and 422, that is to say opposite the volume V2. The casing 90 is immobilized on the plate 22 by means of screws 47.

Two bearings 900 and 902 are respectively provided in the casing 90 to support the ends of the cranks 408 and 428 opposite the rockers 404 and 424 on which they are respectively fixed. Two bearings 920 and 922 are respectively arranged in the bearings 900 and 902 to support the cranks 408 and 428 in the bearings 900 and 902, with the possibility of rotation, respectively around the axes X40 and X42. More specifically, the ends of the cranks 408 and 428 opposite the rockers 404 and 424 are mounted in the inner rings of the bearings 920 and 922, while the outer rings of these bearings are immobilized in the bearings 900 and 902.

In practice, the bearings 900 and 902 are formed by caps mounted in corresponding housings 904 and 906 formed in the bottom wall 92 of the casing 90 which is parallel to the plate 22. Each cap 900, respectively 902, is formed by a ring 900A, 902A respectively, and a cover 900B, 902B respectively. The bearings 900 and 902 are therefore blind.

The mounting of the bearings or caps 900 and 902 in the housings 904 and 906 of the casing 90 makes it possible to adjust the position of the bearings 920 and 922 with respect to the casing 90 and to solve a possible problem of hyper-statism of the oscillating shafts 40 and 42, due to the installation of three bearings along the length of each of these shafts. The rings 900A and 902A are mounted with play in the housings 904 and 906 and are positioned radially according to the actual positions of the bearings of the shafts 40 and 42 in the plates 22 and 24 and the actual geometry of the shafts 40 and 42. once positioned, they are tightened by screws parallel to the axes X40 and X42 on the bottom wall 92 of the casing 90. The caps 900 and 902 are therefore adjustable radially with respect to the axes X40 and X42.

Bearings 920 and 922 can be the same type or a different type from bearings 620, 640, 622 and 642. For example, bearings 920 and 922 are roller bearings.

Thanks to the bearings formed by the caps 900 and 902, the oscillating shafts 40 and 42 are supported at their two ends, both at the level of the plate 24 and at the level of the housing 90. In other words, the cranks 408 and 428 are not cantilevered beyond the control plate 22 with respect to the area located between the two plates 22 and 24, which avoids the risk of deformation of the shafts 40 and 42 during operation of the shedding device 2, especially for the lower oscillating shaft 42 which would be the most subject to deformations in the absence of the bearing 902 because its crank 428 is furthest from the control plate 22

This shedding device 2 can therefore operate reliably at high speed, in particular at speeds greater than 1000 picks/minute.

The casing 90 contains the two eccentrics 74 and 76, the two control rods 84 and 86 and the two cranks 408 and 428. The contour of the casing 90 in contact with the plate 22 is continuous and provided with a seal 93 The housing 90 supports a bearing 94 of the input shaft 72 which is also provided with a seal. The housing 90 defines a closed volume capable of receiving oil which can ensure the lubrication of the bearings 220, 222, 900, 902 and of the bearing 94 of the input shaft 72.

In the second embodiment of the invention shown in figure 5 , elements similar to those of the first embodiment have the same references. In what follows, only what distinguishes this embodiment from the previous one is described.

In this embodiment, a single bearing 902 is formed in the housing 90 to support the crank 428, while the crank 408 extends cantilevered beyond the bearing 220 with respect to the control plate. 22. In other words, only the oscillating shaft 42 which is driven by the first distal control rod 84 is supported by three bearings 222, 242 and 902. Each of these bearings is equipped with a bearing 622, 642 or 922.

This embodiment is suitable for small format looms, for example whose harness comprises less than 2688 collars, for which it is possible to support by means of only two bearings 220 and 240 the upper oscillating shaft 40 driven by the second proximal connecting rod 86, insofar as the torque produced by the deformation force applied by this connecting rod to the crank 408, relative to the bearing 220 of the plate 22, is relatively limited, in all cases more limited than the torque produced by the deformation force applied by the first distal connecting rod 84 on the crank 428 with respect to the bearing 242.

The invention is represented in the case where the oscillating shaft driven by the first distal connecting rod 84 is the lower oscillating shaft 42. It is however applicable to the opposite case where it is the upper oscillating shaft 40 which is driven by the first distal link. In this case, if a single bearing is provided in the housing 90 as in the second embodiment, this bearing supports the upper oscillating shaft 40.

The invention is not limited to the case where the two series of knives 12 and 14 are connected to the drive bars by connecting rods such as the connecting rods 26. In particular, the invention can be applied to the case where the two series of knives are each grouped together on a frame of claws suspended from two drive bars.

According to a variant of the invention, not shown, some or all of the bearings 220, 222, 240, 242, 900 and 902 can be plain bearings, without bearings. The parts 404, 408, 424 and 428 of the shafts 40 and 42 are then directly articulated in these bearings.

According to another variant of the invention, not shown, the caps are omitted and the bearings 900 and/or 902 are made directly in the wall 92 of the casing 90.

Claims (10)

1. A shed forming device (2) for a Jacquard loom (M), comprising:

   - two series of longitudinal blades (12,14) extending parallel to a longitudinal axis (X2) of the shed forming device, driven in an alternating vertical movement (F2) in phase opposition and coupled, at each of their ends, to a driving bar (30, 32, 34, 36);

   - an upper oscillating shaft (40) and a lower oscillating shaft (42) that extend one above the other and that are respectively provided, at each of their ends, with two tilting levers (405, 406, 425, 426) each coupled to a driving bar by a connecting rod (50, 52);

   - two chassis platens (22, 24), between which the two series of knives and the oscillating shafts extend and which are provided with articulation bearings (220, 222, 240, 242) of the oscillating shafts;

   - an input shaft (72) driven by a continuous rotational movement (F3) and equipped with a first eccentric (74) and a second eccentric (76) that are positioned near a first platen (22), among the two chassis platens (22, 24), outside a volume (V2) defined between these platens, the first eccentric driving a first control connecting rod (84) hitched to a first crank (428) belonging to a first oscillating shaft (42), among the two oscillating shafts (40, 42), the second eccentric driving a second control connecting rod (86_ hitched to a second crank (408) belonging to the second oscillating shaft (40), among the two oscillating shafts, and the first control connecting rod being further from the first platen, along the longitudinal axis (X2), than the second control connecting rod,

   characterized in that the two eccentrics (74, 76), the two control connecting rods (84, 86) and the two cranks (408, 428) are contained in a casing (90) that supports at least one additional articulation bearing (902) of the first oscillating shaft (42).
2. The shed forming device according to claim 1, characterized in that the casing (90) further supports an additional articulation bearing (900) of the second oscillating shaft (40).
3. The shed forming device according to one of the preceding claims, characterized in that the first oscillating shaft is the lower oscillating shaft (42).
4. The shed forming device according to any one of claims 1 or 2, characterized in that the first oscillating shaft is the upper oscillating shaft (40).
5. The shed forming device according to one of the preceding claims, characterized in that each oscillating shaft (40, 42) comprises a hollow tube (402, 404) fastened, at each of its ends, on a cradle (404, 424) that includes two tilting levers (405, 406, 425, 426) and each cradle is articulated in a bearing (220, 222, 240, 242) of one of the chassis platens (22, 24).
6. The shed forming device according to claim 5, characterized of the diameter of the hollow tube (402, 404) of an oscillating shaft (40, 42) is comprised between 80 and 160 mm, preferably between 100 and 140 mm, still more preferably in the order of 120 mm.
7. The shed forming device according to one of claims 5 or 6, characterized in that the first crank (428) is fastened on a cradle (424) of the first oscillating shaft (42) and articulated in the bearing (902) supported by the casing (90).
8. The shed forming device according to one of the preceding claims, characterized in that each articulation bearing (900, 902) supported by the casing is equipped with a rolling bearing (920, 922) in which part (408, 428) of one of the oscillating shafts (40, 42) is introduced.
9. The shed forming device according to one of the preceding claims, characterized in that each articulation bearing supported by the casing (90) is formed by a cap (900, 902) that is radially adjustable relative to the axle (X40, X42) of the oscillating shaft (40, 42), mounted in a housing (902, 904) of a wall (92) of the casing and clamped on the wall of the casing.
10. A Jacquard loom (M) comprising a shed forming device (2) according to one of the preceding claims.

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